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J Kato

Publications and source records attributed to J Kato.

At least 19 recordsLinked to original sources
PubMed2007

Total body irradiation and granulocyte colony-stimulating factor-combined high-dose cytarabine as a conditioning regimen in allogeneic hematopoietic stem cell transplantation for advanced myelodysplastic syndrome: a single-institute experience.

In this study, we retrospectively evaluated the efficacy and safety of total body irradiation (TBI) and granulocyte colony-stimulating factor (G-CSF)-combined high-dose cytarabine as a conditioning regimen for allogeneic hematopoietic stem cell transplantation (HSCT) in patients with advanced myelodysplastic syndrome (MDS). We evaluated 22 patients with advanced MDS, including refractory anemia with excess blasts (RAEB; n=10), RAEB in transformation (n=2), acute myelogenous leukemia transformed from MDS (n=6) and chronic myelomonocytic leukemia (n=4). The conditioning regimen consisted of 12 Gy of TBI and high-dose cytarabine (3 g/m(2)) every 12 h for 4 days, and the cytarabine was combined with continuous administration of G-CSF. The stem cell sources were bone marrow or peripheral blood stem cells from human leukocyte antigen (HLA)-identical siblings (n=12) and bone marrow from HLA serologically matched unrelated donors (n=10). Three patients experienced disease relapse, two of whom died of disease progression. Of 22 patients, 16 are currently alive and disease-free. The 5-year estimated overall survival, disease-free survival, relapse and non-relapse mortality rates are 76.7, 72.2, 16.6 and 14.1%, respectively. These results suggest that G-CSF-combined high-dose cytarabine could be a promising component of the conditioning regimen of allogeneic HSCT for advanced MDS, providing a low incidence of both relapse and treatment-related mortality.

Adolescent↗
PubMed2006

Clinical characteristics of synchronous colorectal cancer are different according to tumour location.

AIMS: The purpose of this study was to investigate the clinical characteristics of synchronous cancer patients, with particular attention given to variations in tumour location. METHODS: A retrospective evaluation of 249 synchronous cancer cases out of 3061 consecutive colorectal cancer patients. RESULTS: Multivariate analysis of risk factors for synchronous cancer according to tumour location revealed that male gender was a significant risk for synchronous lesions in the left colon only (odds ratio=2.05, 95% confidence interval 1.34-3.13). Meanwhile, aging was a risk factor for synchronous cancer in the right colon only (odds ratio=1.05, 95% confidence interval 1.02-1.08), and in both sides of the colon (odds ratio=1.03, 95% confidence interval 1.01-1.05), but not in the left colon only (odds ratio=0.98, 95% confidence interval 0.97-1.00). In addition, patients with synchronous lesions in the right colon only tended to have adenomas in the right colon, while those with synchronous lesions in the left colon only tended to have adenomas in the left colon (each P value <0.05). CONCLUSION: The risk factors and status of concurrent adenomas of synchronous cancer cases varied according to tumour location, suggesting that the colonic site susceptible to neoplasia varies according to patient characteristics.

Adenoma↗
PubMed2006

Therapeutic efficacy of leukocytapheresis in a pregnant woman with severe active ulcerative colitis.

Leukocytapheresis has recently been used to induce remission in patients with ulcerative colitis (UC) who fail to respond to corticosteroids. We could not find a report in the literature on leukocytapheresis for UC with gestational exacerbation. We have recently encountered this unique condition and report the details here. A 30-year-old Japanese woman with left-sided severe UC was corticosteroid-dependent and had recurrence of the active disease during tapering of corticosteroid. She declined any dose increase and the use of any immunosuppressive agent because she was in the 13th week of pregnancy. Then, concomitant leukocytapheresis was performed without increasing the corticosteroid dose. Recovery was rapid and dramatic. Mucous and bloody stool decreased after the first session, and she had remission 2 weeks later. She underwent a total of four sessions without complications. After 6 weeks, she was discharged from our hospital and underwent maintenance treatment as an outpatient with mesalazine and corticosteroid tapering. Subsequently, she gave birth to a healthy baby girl by an uncomplicated vaginal delivery while keeping the remitted stage of UC.

Adult↗
PubMed2006

Plasma adrenomedullin level and development of hypertension.

The hypotensive peptide adrenomedullin (AM) is assumed to act as a factor inhibitory on elevation of blood pressure and on progression of the hypertensive organ damage, and plasma AM levels are elevated in patients with hypertension. The aim of the present study is to explore whether or not a rise in plasma AM levels precedes the development of hypertension. Normotensive local residents without apparent cardiovascular or renal disease (n = 177) were divided into low and high AM groups based on the median concentration of AM in plasma (11.9 fmol/ml), and followed up for 3 years for development of hypertension. The incidence of hypertension was higher in the residents with high AM than low AM levels (27.8 vs 11.5%, P < 0.01), whereas a similar analysis of plasma levels of atrial or brain natriuretic peptides revealed no such difference. The plasma AM level was found to be a significant parameter for the development of hypertension in a univariate analysis (P < 0.01), but not in a multivariate analysis. Meanwhile, the plasma AM level was significantly (P < 0.01) correlated with age and body mass index (BMI), two variables independently significant for the development of hypertension. The present findings suggest that an elevation of the plasma AM level associated with aging and increased BMI precedes the development of hypertension in the normotensive subjects.

Adrenomedullin↗
PubMed2006

Hepatitis C virus core protein promotes proliferation of human hepatoma cells through enhancement of transforming growth factor alpha expression via activation of nuclear factor-kappaB.

BACKGROUND: Hepatitis C virus (HCV) infection is a major cause of human hepatocellular carcinoma (HCC). The precise mechanism of hepatocarcinogenesis in humans by HCV is currently unclear. It was recently shown, however, that transgenic mice with the HCV core gene often develop HCC, suggesting tumorigenic activity of the HCV core protein. Further, the HCV core protein expressed in HepG2 cells transfected with the core gene was shown to stimulate proliferation of transfectants through activation of nuclear factor-kappaB (NF-kappaB). The downstream target molecule(s) of NF-kappaB activated by the HCV core protein to evoke cell proliferation is not yet identified. Transforming growth factor (TGF) alpha, which is often overexpressed in various tumour tissues such as HCC, has been shown to stimulate hepatocyte proliferation through activation of the mitogen-activated protein kinase or extracellular signal-related protein kinase (MAPK/ERK) cascade. AIMS: To explore the possibility that TGFalpha might be a target molecule for NF-kappaB activated by the HCV core, and that TGFalpha participates in the growth promotion of the core transfectants in an autocrine manner, activating the MAPK/ERK pathway. METHODS: A HCV core expression vector was transfected into human hepatoma Huh-7, HepG2 and Hep3B cells. NF-kappaB activity was examined by an electrophoretic mobility shift assay. TGFalpha transcription was assessed by a luciferase reporter assay. TGFalpha protein was determined by immunoblot and ELISA. MAPK/ERK activity was examined by an in vitro kinase assay. Cell proliferation was assessed by a water-soluble tetrazolium salt-1 assay. RESULTS: In the HCV core transfectants, NF-kappaB bound to the kappaB site in the TGFalpha proximal promoter region, resulting in an increase in TGFalpha transcription. Immunoblot as well as ELISA showed increased TGFalpha expression in the HCV core transfectants. SN50, a specific inhibitory peptide for NF-kappaB, cancelled HCV core-induced TGFalpha expression. HCV core protein increased cell proliferation as well as ERK activity of the HCV core transfectants as compared with the mock transfectants. The growth-promoting activity and activation of ERK by the HCV core protein were negated by treatment with anti-TGFalpha antibodies. CONCLUSIONS: These results suggest that the HCV core protein promotes proliferation of human hepatoma cells by activation of the MAPK/ERK pathway through up regulation of TGFalpha transcription via activation of NF-kappaB. Our finding provides a new insight into the mechanism of hepatocarcinogenesis by HCV infection.

Carcinoma, Hepatocellular↗
PubMed2006

Endoscopic submucosal dissection for early gastric cancer: results and degrees of technical difficulty as well as success.

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) is a new method for the curative treatment of early gastrointestinal neoplasms, which was developed in order to increase the en bloc and R0 resection rate, especially for lesions larger than 20 mm in diameter. Drawbacks of ESD include the fact that it is technically a substantially more difficult procedure and that it is associated with a higher perforation rate. A retrospective study was therefore carried out to analyze cases in relation to the procedure time and resection success, and these factors were correlated with the characteristics of the lesions. PATIENTS AND METHODS: From January 2002 to November 2005, 196 lesions in 185 patients with early gastric cancer were treated using ESD in our hospital. The rates of curative en bloc resection, the incidence of perforation, and the procedure times were analyzed in relation to lesion size (small, 20 mm or less in diameter; large, over 20 mm), location (upper, middle, or lower third of the stomach) and the presence or absence of ulceration. RESULTS: The rate of curative en bloc resection was 84 % (93 % of the lesions overall were resected in one piece), with a perforation rate of 6.1 % (all perforations were managed endoscopically) and a mean procedure time of 68 min. The rate of curative en bloc resection differed significantly depending on the location of the lesion (upper vs. middle vs. lower, 74 % vs. 77 % vs. 91 %; P < 0.05), as well as on the size of the lesion (> 20 mm vs. 20 mm or less, 59 % vs. 89 %; P < 0.0001). There were also significant differences in the mean procedure times in relation to the location of the lesion (upper vs. middle vs. lower, 105 min vs. 81 min vs. 45 min; P < 0.0001) and the size of the lesion (> 20 mm vs. 20 mm or less, 124 min vs. 55 min; P < 0.0001), as well as the presence of ulceration (positive vs. negative, 97 min vs. 65 min; P < 0.05). With regard to perforation rates, significant differences were also observed in relation to the location of the lesion (upper vs. middle vs. lower, 22.6 % vs. 2.8 % vs. 3.2 %; P < 0.0005) and size of the lesion (> 20 mm vs. 20 mm or less, 16.2 % vs. 3.8 %; P < 0.005). No local recurrences of curatively resected lesions (n = 119) were observed after a follow-up period of 1 year. CONCLUSIONS: The difficulty of ESD depends on the location and size of the lesion, as well as on the presence of ulceration. We would recommend that trainees should begin by carrying out ESD on lesions with a diameter of less than 20 mm without ulceration that are located in the lower third of the stomach.

Adult↗
PubMed2005

Involvement of transforming growth factor-beta and thrombopoietin in the pathogenesis of myelodysplastic syndrome with myelofibrosis.

We investigated the cause of myelofibrosis and proliferation of megakaryocytes in myelodysplastic syndrome with myelofibrosis (MDS-MF (+)). Plasma-transforming growth factor-beta1 (PTGF-beta1) concentrations closely correlated with myelofibrosis grade in MDS-MF (+) and were higher than those in idiopathic myelofibrosis (IMF), essential thrombocythemia (ET), idiopathic thrombocytopenic purpura (ITP), MDS-without MF (MDS-MF (-)) or healthy volunteers (HV). Peripheral blood mononuclear cells from MDS-MF (+) patients expressed more TGF-beta1 mRNA than those from IMF, MDS-MF (-) or HV. When we immunostained bone marrow specimens of MDS-MF (+) for TGF-beta, the intensity of blasts was apparently higher than that of megakaryocytes, while in MDS-MF (-), megakaryocytes were immunostained with a similar intensity as that in MDS-MF (+), but blasts were negative for staining. In IMF, megakaryocytes, monocytes and small mononuclear cells representing CD34+ cells were all similarly stained with a much lower intensity than that of blasts in MDS-MF (+). The number of bone marrow megakaryocytes were increased the most in MDS-MF (+), followed by ET, ITP, MDS-MF (-) and NHL and correlated with plasma thrombopoietin (TPO) levels or with plasma TGF-beta1 levels, respectively, in each disease. Thus, in MDS-MF (+), both myelofibrosis and the increased megakaryocytes were ascribed to overproduction of TGF-beta1 from blasts.

Adult↗
PubMed2003

Unilateral compatibility and genotypic difference in crossability in interspecific hybridization between Dianthus caryophyllus L. and Dianthus japonicus Thunb.

Reciprocal interspecific crosses were carried out between six lines of Dianthus caryophyllus L. and one line of Dianthus japonicus Thunb. Although no seed was set when D. japonicus was used as the seed parent, six seedlings were successfully obtained from 2,380 immature ovules by applying the embryo-rescue technique. However, they showed seed parent-like morphology and no evidence for the hybridity by flow cytometry and RAPD analyses. When six lines of D. caryophyllus were used as seed parents, a total of 192 seedlings were successfully obtained without using the embryo-rescue technique. Among these seedlings, 12 out of 25 progenies obtained from the carnation line '98sp1651' were confirmed to be the hybrids. The remaining 13 progenies of this line, and the total 167 progenies obtained from the other carnation lines, had carnation-like morphology without any evidence of hybridity by flow cytometry and RAPD analyses. The progenies confirmed as hybrids had intermediate characters of the parents with respect to leaf width and flower size, but they had a uniform flower color, reddish purple, which was different from that of either parent. Since the hybrids obtained in the present study have some profitable characters such as vigorous growth in summer time, upright robust stem, broad leaves and early flowering, they are expected to be used for the breeding of carnation which is suitable for growing under the Japanese climate.

DNA, Plant↗
PubMed2003

Argon plasma coagulation for successful treatment of early gastric cancer with intramucosal invasion.

BACKGROUND: In recent years, there has been an increasing number of cases of early gastric cancer (T1, NX) with intramucosal invasion, which are untreatable by surgical or endoscopic mucosal resection (EMR) because of their high risk. Currently, no adequate treatment is available for such patients. AIM: The main objective of this study was to evaluate whether argon plasma coagulation (APC) is an effective and safe modality for treating early gastric cancer untreatable by surgical resection or EMR. METHODS: The study group comprised 20 men and seven women diagnosed with gastric cancer with intramucosal invasion who were considered poor candidates for surgical resection or EMR due to risk factors such as severe cardiac failure or thrombocytopenia. Irradiation conditions for APC treatment were determined using swine gastric mucosa. We used an argon gas flow of 2 l/min at a power setting of 60 W and a maximum irradiation time of 15 s/cm(2). The follow up period of the 27 patients ranged from 18 to 49 months (median 30 months). RESULTS: All lesions were irradiated easily, including areas anatomically difficult for EMR such as the gastric cardia or the posterior wall of the upper gastric body. In 26 of 27 patients (96%) there was no evidence of recurrence during the follow up period (median 30 months). One patient showed recurrence six months after the treatment but was successfully retreated. No serious complications were found in any of the 27 patients but three patients (11%) experienced a feeling of abdominal fullness. INTERPRETATION: APC is a safe and effective modality for treatment of early gastric cancer with intramucosal invasion untreatable by surgical resection or EMR. However, further observations are necessary to determine the long term prognosis of patients undergoing this treatment.

Adenocarcinoma↗
PubMed2002

Successful treatment of advanced peripheral T-cell lymphoma with an angiocentric growth pattern complicated with hemophagocytic syndrome by high-dose chemotherapy and autologous peripheral blood stem cell transplantation.

Peripheral T-cell lymphomas (PTCL) account for about 10% of all lymphomas in Western countries, respond poorly to therapy, and have short survival with no sustained remission. Furthermore, the complication of hemophagocytic syndrome (HPS) sometimes makes the prognosis of this disease extremely worse. We report here a case of PTCL with an angiocentric growth pattern complicated with HPS successfully treated by high-dose chemotherapy and autologous peripheral blood stem cell transplantation. Our case suggests this approach is an excellent candidate for the treatment of this disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

A case of true malignant histiocytosis: identification of histiocytic origin with use of immunohistochemical and immunocytogenetic methods.

We report here an autopsy case of true malignant histiocytosis. The patient was a 67-year-old woman who exhibited fever, wasting, hepatosplenomegaly, and progressive pancytopenia. The bone marrow aspiration disclosed hemophagocytosing cells, which resembled histiocytes. The molecular analysis did not show the clonal gene rearrangement of T-cell receptor or immunoglobulin heavy chain. Although the patient had been started on methylprednisolone pulse therapy and chemotherapy with etoposide, she died from cerebral hemorrhage. The autopsy specimens of spleen and liver showed extensive infiltration of atypical cells, for which histiocytic origin was identified with an immunohistochemical method using monoclonal antibodies against CD11c, CD68, macrophage colony-stimulating factor (M-CSF), M-CSF receptor, lysozyme, antitrypsin and alpha1-antichymotrypsin. Recent investigations have disclosed that in most cases diagnosed as malignant histiocytosis, hemophagocytosis was reactive and not evoked by histiocytic malignancy. True malignant histiocytosis, for which histiocytic origin is confirmed, is extremely rare.

Aged↗
PubMed2002

Efficient selection of genomic clones from a female chicken bacterial artificial chromosome library by four-dimensional polymerase chain reactions.

A bacterial artificial chromosome (BAC) library consisting of 49,152 genomic clones was constructed from partially HindIII-digested female chicken embryo genomic DNA using the pBAC-Lac vector and maintained in 512 96-well plates. The mean insert size was approximately 150 kb, and the total library was estimated to contain about 3.2 times coverage of the diploid genome. In order to screen this library by the PCR, 296 BAC clone DNA samples were prepared: one sample each from 8 superpools (64 plates per superpool) and 36 samples of four-dimensionally (4-D) mixed clones from each superpool. A BAC clone of interest was selected by two-step PCR. First, 8 DNA samples representing superpools were subjected to PCR with a set of primers to amplify a part of the genomic sequence of interest. Second, 36 4-D DNA samples from the superpool that contained BAC clone(s) of interest were subjected to PCR with the same set of primers. The second step identified a plate and a well containing the BAC clone of interest. Selection of target BAC clone(s) from the whole library with the above procedure can be achieved within 1 to 4 d without using a radioactive probe. This procedure was applied successfully in the selection of BAC clones for Wpkci, chPKCI/HINT, ZOV3, and 17beta-HSD genes.

Amino Acid Sequence↗
PubMed2002

Denatured H-ferritin subunit is a major constituent of haemosiderin in the liver of patients with iron overload.

BACKGROUND AND AIMS: Iron is stored in hepatocytes in the form of ferritin and haemosiderin. There is a marked increase in iron rich haemosiderin in iron overloaded livers, and ferric iron in amounts exceeding the ferritin and haemosiderin binding capacity may promote free radical generation, causing cellular damage. The aim of this study was to characterise hepatic haemosiderin using four antibodies specific for either native or denatured H/L-ferritin subunits. METHODS: Ferritin and haemosiderin were prepared from the livers of three patients with post-transfusional iron overload. The assembled ferritin molecules were analysed by non-denaturing polyacrylamide gel electrophoresis (PAGE)-immunoblotting. Ferritin subunits in the haemosiderin fraction were assessed by denaturing sodium dodecyl sulphate (SDS)-PAGE-immunoblotting. Distribution of native and denatured ferritin subunits in hepatocytes was examined by immunogold electron microscopy. RESULTS: Non-denaturing PAGE-immunoblot analyses showed that the assembled liver ferritins were recognised by the antibodies for native ferritins and not by those for the denatured subunits. Both SDS-PAGE-immunoblot and immunogold electron microscopic analyses disclosed that haemosiderin of iron overloaded liver reacted predominantly to the monoclonal antibody for the denatured H-ferritin subunit, to a lesser degree to that for denatured L-ferritin, and very weakly, if any, with antibodies for native H-ferritin or L-ferritin. CONCLUSIONS: These results suggest that in iron overloaded liver, haemosiderin consists predominantly of denatured H-ferritin subunits.

Adult↗
PubMed2002

Exercise-induced acute renal failure with renal hypouricemia: a case report and a review of the literature.

A previously healthy 16-year-old boy developed acute renal failure following a track race at a local athletic meeting. Several hours after the run, he expressed pain in the loins with nausea and vomiting. After 3 sessions of hemodialysis, he was referred to our hospital. On admission, serum creatinine was elevated to 2.3 mg/dl without an increase in serum uric acid level. After recovery from acute renal failure (ARF), hypouricemia (0.7 mg/dl) became evident in the patient. One year later, he suffered from ARF after a track race with the highest creatinine levels of 1.1 mg/dl. In order to clarify the cause and prognosis of ARF with renal hypouricemia, we summarized the clinical features in 18 patients previously described and our patient. Serum uric acid levels after recovery from ARF were below 1.0 mg/dl in all patients. Renal biopsy in 9 patients showed acute tubular necrosis in 8 patients and uric acid nephropathy in 1. The short-term prognosis of these patients seemed good, although 5 patients needed to undergo hemodialysis in their ARF courses. However, the recurrence of ARF episodes occurred in 6 patients (31.6%) including our patient, indicating that prevention of ARF might be necessary in these patients. More information is required to establish guidance for prevention of ARF.

Acute Kidney Injury↗
PubMed2001

Normalization of elevated hepatic 8-hydroxy-2'-deoxyguanosine levels in chronic hepatitis C patients by phlebotomy and low iron diet.

Accumulation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in DNA, which may result from the continuous reactive oxygen species (ROS) generation associated with chronic inflammation, has been reported in various human preneoplastic lesions and in cancerous tissues. However, no direct causative relationship between the 8-OHdG formation and carcinogenesis has been thus far demonstrated in humans. Directly proving the causality requires showing that depletion of 8-OHdG levels in tissue by interfering with ROS generation results in a reduction in cancer. Chronic hepatitis C virus (HCV) infection is associated with a high risk of hepatocellular carcinoma (HCC). Several studies on patients with chronic HCV have shown that hepatic iron overload is attributable to liver injury and that iron depletion improved serum aminotransferase levels. Excess iron is known to generate ROS within cells, which causes mutagenic lesions, such as 8-OHdG. In this study, therefore, we have evaluated whether therapeutic iron reduction (phlebotomy and low iron diet) with a long-term follow-up (6 years) would decrease the hepatic 8-OHdG levels and the risk of HCC development in patients with chronic HCV. Patients (34) enrolled were those who had undergone standard IFN therapy but had no sustained response. Quantitative immunohistochemistry using the KS-400 image analyzing system and electrochemical detection was used for 8-OHdG detection. With this treatment, elevated hepatic 8-OHdG levels in patients with chronic hepatitis C (8.3 +/- 4.6/10(5) dG) significantly decreased to almost normal levels (2.2 +/- 0.9/10(5) dG; P < 0.001) with concomitant improvement of hepatitis severity, including fibrosis, whereas HCV titers were unaffected. None of these patients developed HCC. Thus, long-term iron reduction therapy in patients with chronic hepatitis C may potentially lower the risk of progression to HCC.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2001

Systematic analysis of the TGF-beta-Smad signaling pathway in gastrointestinal cancer cells.

The transforming growth factor-beta (TGF-beta)-Smad signaling pathway has an important role in carcinogenesis. To study the frequency and mechanism of functional impairment of this pathway in human gastrointestinal cancers, we used a reporter assay to examine the response of 38 cell lines (11 colorectal, 9 pancreatic, 10 gastric, and 8 hepatic cancers) to TGF-beta. We then analyzed TGF-beta type II receptor (T beta RII) gene, immunoblots of Smad4, and restoration of the pathway by rescuing T beta R or Smad. We observed impaired signaling in 91% of colorectal, 67% of pancreatic, and 40% of gastric cancer cell lines, but in none of the hepatic cancer cells. We suggest that this pathway does not function as a tumor suppressor in hepatic carcinogenesis. The impairment is due to inactivation of T beta RII and Smad4 in colorectal and pancreatic cancers. However, because the signal was not recovered by rescuing T beta R or Smad genes in TGF-beta-response-defective gastric cancer cell lines, we suggest that novel molecules or mechanisms are involved in the impaired pathway in some gastric cancers.

Blotting, Western↗