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T Shimomura

Publications and source records attributed to T Shimomura.

At least 19 recordsLinked to original sources
PubMed2006

Population dynamics of anaerobic microbial consortia in thermophilic methanogenic sludge treating paper-containing solid waste.

To maintain a stable thermophilic (55 degrees C) anaerobic digestion treating toilet paper-containing garbage, it is necessary to operate the digester at long hydraulic retention time (HRT) and low organic loading rate (OLR). Critical conditions of the digestion were investigated by operating the digester at HRT 23 days and OLR 3.4 gCOD(Cr)/L/d (R1) or HRT 14 days and OLR 5.6 gCOD/Cr)/L/d (R2) separately. Characteristics of methanogenesis of the two digesters were examined by measuring gas generation volume and volatile fatty acids (VFA) concentration, and the populations of four anaerobic acidogens and three methanogens were analyzed using quantitative PCR method. In digester R1, methanogenic activity was unstable but it could be recovered by stopping feeding as though VFA accumulation occurred. The population of acidogens and two methanogens were maintained at 10(11) - 10(13) copies/L, however, the population of Methanoculleus could not be recovered after methanogenesis recovering. In digester R2, the period of methanogenesis was significantly shorter than that in digester R1. Both the acidogens and the methanogens could not be maintained at a stable concentration. It is suggested that the critical HRT to sustain the population of acidogens in this process should be longer than 14 days and for all kinds of methanogens, HRT should be longer than 23 days.

Acids↗
PubMed2006

[Extracorporeal membrane oxygenation for severe respiratory failure during thoracic aortic aneurysm repair].

We present a case of successful management for severe respiratory failure during thoracic aortic aneurysm repair by applying extracorporeal membrane oxygenation (ECMO). The patient was a 71-year-old man who was diagnosed as thoracic aortic aneurysm and coronary artery stenosis. Severe respiratory failure occurred during operation because of pulmonary hemorrhage, and it was difficult to wean from cardiopulmonary bypass. ECMO was provided for improvement of oxygenation and CO2 removal. Pulmonary hemorrhage was controlled by strict management of coagulation system, and ECMO was discontinued after improvement of oxygenation on the 4th postoperative day. It is considered that early application of ECMO was effective in this case.

Aged↗
PubMed2004

[Successful treatment for tachyarrhythmia with ultra short acting beta-blocker during beating coronary artery bypass grafting; report of a case].

A 62-year-old man with supraventricular/ventricular tachycardia associated with myocardial infarction developed tachycardia during beating coronary artery bypass grafting (CABG). Intravenous administration of an ultra short acting beta-blocker, landiolol hydrochloride, controlled heart rate and improved tachyarrhythmia without significant change of blood pressure. Landiolol hydrochloride is effective and useful for the treatment of tachyarrhythmia during beating CABG.

Adrenergic beta-Antagonists↗
PubMed2004

[Surgery for acute aortic dissection concomitant with preceding axillofemoral bypass to prevent malperfusion of visceral organs and limb ischemia].

A 52-year-old man was admitted with sudden onset of epigastralgia. Abdominal X-ray showed dilated intestine and computed tomography (CT) revealed extended type A aortic dissection. Marked abdominal distention and weak pulse of right femoral artery were recognized so malperfusion of visceral organs due to narrowing true lumen compressed by thrombosed false lumen was suggested. In the operation, right axillo-right femoral bypass was established preceding to median sternotomy. This graft was used as an arterial perfusion site of cardiopulmonary bypass, and replacement of the ascending aorta was performed under hypothermic circulatory arrest and retrograde cerebral perfusion. Sign of malperfusion of visceral organs was showed for several days after the operation but it disappeared without further intervention. Axillofemoral inflow of cardiopulmonary bypass may be effective procedure in these cases.

Anastomosis, Surgical↗
PubMed2001

Expression of hepatocyte growth factor activator and hepatocyte growth factor activator inhibitor type 1 in human hepatocellular carcinoma.

Hepatocyte growth factor activator inhibitor type 1 (HAI-1), a Kunitz-type serine protease inhibitor for hepatocyte growth factor activator (HGFA), is responsible for proteolytic activation of hepatocyte growth factor. We examined the expression of HGFA and HAI-1 in liver tissues of chronic liver diseases including hepatocellular carcinoma (HCC). HGFA expression was detected not only in the liver tissues of chronic hepatitis and cirrhosis and in the nontumorous liver tissues surrounding HCC, but also in HCC tissues. On the other hand, none of the liver tissues of hepatitis and cirrhosis and none of the nontumorous tissues surrounding HCC were stained with anti-HAI-1. However, 35% of HCC tissues were stained with anti-HAI-1, and HAI-1 positivity increased as the histological grade decreased and as serum alpha-fetoprotein increased. Transduction of antisense HAI-1 inhibited the growth of human hepatoma cells. These results suggest the possibility that HAI-1 plays an important role in the progression of HCC.

Base Sequence↗
PubMed2001

Identification of hepatocyte growth factor activator inhibitor type 2 (HAI-2)-related small peptide (H2RSP): its nuclear localization and generation of chimeric mRNA transcribed from both HAI-2 and H2RSP genes.

A novel small gene, designated hepatocyte growth factor activator inhibitor type 2 (HAI-2)-related small peptide (H2RSP) was cloned and characterized in the process of the search for splicing variant forms of HAI-2 by 3'-rapid amplification of cDNA ends (RACE). The gene consisted of 4 exons spanning approximately 1 kb and was located in 11 kb downstream of HAI-2 gene (19q.13.11). The novel transcript identified by 3'-RACE was thought to be chimerically transcribed from both HAI-2 (exons 1-7) and H2RSP (exons 2-4) genes. Wild-type H2RSP mRNA (0.5 kb) was detected abundantly in various tissues including the gastrointestinal tract, whereas chimeric mRNA (1.5 kb) was found mainly in the kidney, prostate, and placenta by Northern blot analysis. The predicted amino acid sequence of H2RSP contained two unique domains, namely the serine-rich region (exon 3) and the lysine-rich region (exon 4). Transfection of deleted series of H2RSP cDNAs fused to enhanced green fluorescent protein (EGFP) into HeLa cells revealed that H2RSP has nuclear localization signal in the lysine-rich region. Immunohistochemical study using anti-H2RSP polyclonal antibody indeed revealed the nuclear localization of this peptide in vivo. These results suggest that H2RSP and H2RSP/HAI-2 chimeric peptides might function as a transcriptional regulatory peptide at the nucleus.

Amino Acid Sequence↗
PubMed2001

Endomucin is expressed in embryonic dorsal aorta and is able to inhibit cell adhesion.

Recent studies have suggested the existence of progenitors common to hematopoietic and endothelial cells, called hemangioblasts, in, for instance, embryonic dorsal aorta. To identify a membrane-bound or secretory molecule regulating early hematopoiesis, we screened a cDNA library from dorsal aortas of embryonic day (E) 10.5 mice by a signal sequence trap method and obtained a clone encoding a sialoprotein, endomucin-1. Immunohistochemistry revealed that the endomucin-1 transcript was specifically expressed in the endothelial cells of dorsal aorta of E10.5 mouse embryo. Overexpression of endomucin-1 strongly inhibited adhesion and aggregation of cells, including cultured endothelial cells from E10.5 dorsal aorta. These data suggest that endomucin-1 may play a role in detachment of hematopoietic cells from endothelium during early hematopoiesis.

Amino Acid Sequence↗
PubMed2001

Spontaneous regression of recurrent hepatocellular carcinoma after TAE: possible mechanisms of immune mediation.

We report findings in a 76-year-old man who underwent a lateral segmentectomy of the liver for hepatocellular carcinoma in July 1996. In July 1997, transarterial embolization (TAE) was performed for recurrent tumors in the remnant liver. Augmentation of the tumors and an increase in protein induced by vitamin K absence or antagonist (PIVKA)-II level were noted in October 1997, and, although we recommended TAE again, the patient and his family refused further treatment. Subsequently, the patient was only observed, and, except for a small lesion that was probably a scar, no tumors were noted on image examinations in November 1998, and the PIVKA-II level had returned to a normal value at this time. Two years after the regression, the tumors appeared to be in complete spontaneous remission. This patient had no history indicative of ischemic necrosis, and levels of cellular surface markers for natural killer (NK) cells and NK cell activity showed high values, which suggested that tumor immunity was activated by some, unknown, mechanism.

Aged↗
PubMed2001

Clinical features of symptomatic Rathke's cleft cyst.

To investigate the clinical features of Rathke's cleft cysts (RCCs), we retrospectively analyzed 15 cases with histologically confirmed RCCs. All patients underwent formal testing of visual field, endocrinological evaluation and magnetic resonance imagings. As overall presenting symptoms, endocrine disturbance was the most common symptoms, followed by visual disturbance and headache. Among the endocrine disturbances based on adenohypophysial dysfunction, hyperprolactinemia was most common. Considering the size of RCCs, RCCs could induce hyperprolactinemia only when the cysts became large enough to compress the infundibular system. Our series showed relative high incidence of pituitary dwarfism and diabetes insipidus (DI). These facts indicated that RCCs could evoke hyposecretion of growth hormone in young patients and DI in aged patients by direct compression of the pituitary gland in the early stage of progression. All cases who had headache had no other symptoms. We could not prove the evidence that RCCs could induce headaches in these cases. This might be suggested that headache could not be a sole symptom in cases of RCCs.

Adolescent↗
PubMed2001

Involvement of Fc gamma receptor polymorphism in the therapeutic response of idiopathic thrombocytopenic purpura.

Clearance of autoantibody-sensitized platelets through Fc gamma receptors on phagocytic cells is one of the main mechanisms of thrombocytopenia in idiopathic thrombocytopenic purpura (ITP). We examined the Fc gamma RIIA-131R/H and Fc gamma RIIIA-158V/F polymorphisms in 104 adult chronic ITP patients, and in 59 healthy control subjects using polymerase chain reaction-based allele-specific restriction analysis. The frequency of Fc gamma RIIA genotypes (131H/H, H/R, R/R) was not significantly different between patients and controls, and did not correlate with the responsiveness to treatment. In contrast, among Fc gamma RIIIA genotypes, frequency of 158F/F homotype was smaller in ITP (P < 0.05). Furthermore, in Fc gamma RIIIA-158V/V homotype, the complete remission (CR) rate with medication (treatment with corticosteroid or other immunosuppressive agents) was significantly higher (60%) than that in 158V/F (10%) or 158V/F plus 158F/F, (P < 0.01, P < 0.05). Conversely, the CR rate after splenectomy in 158F/F and 158V/F types (64.3% and 54.6%) was higher than in 158V/V (25%). Our results indicate that the polymorphism of Fc gamma RIIIA, but not Fc gamma RIIA, influences the response to treatment in ITP.

Adult↗
PubMed2001

The release of the substrate for xanthine oxidase in hypertensive patients was suppressed by angiotensin converting enzyme inhibitors and alpha1-blockers.

OBJECTIVE: Hyperuricemia is associated with the vascular injury of hypertension, and purine oxidation may play a pivotal role in this association, but the pathophysiology is not fully understood. We tested the hypothesis that in hypertensive patients, the excess amount of the purine metabolite, hypoxanthine, derived from skeletal muscles, would be oxidized by xanthine oxidase, leading to myogenic hyperuricemia as well as to impaired vascular resistance caused by oxygen radicals. METHODS: We investigated the production of hypoxanthione, the precursor of uric acid and substrate for xanthine oxidase, in hypertensive patients and found that skeletal muscles produced hypoxanthine in excess. We used the semi-ischemic forearm test to examine the release of hypoxanthine (deltaHX), ammonium (deltaAmm) and lactate (deltaLAC) from skeletal muscles in essential hypertensive patients before (UHT: n = 88) and after treatment with antihypertensive agents (THT: n = 37) in comparison to normotensive subjects (NT: n = 14). RESULTS: deltaHX, as well as deltaAmm and deltaLAC, were significantly higher in UHT and THT (P< 0.01) than in NT. This release of deltaHX from exercising skeletal muscles correlated significantly with the elevation of lactate in NT, UHT and THT (y = 0.209 + 0.031x; R2 = 0.222, n = 139: P < 0.01). Administration of doxazosin (n = 4), bevantolol (n = 5) and alacepil (n = 8) for 1 month significantly suppressed the ratio of percentage changes in deltaHX by -38.4 +/- 55.3%, -51.3 +/- 47.3% and -76.3 +/- 52.2%, respectively (P< 0.05) but losartan (n = 3), atenolol (n = 7) and manidipine (n = 10) did not reduce the ratio of changes; on the contrary, they increased it in deltaHX by +188.2 +/- 331%, +96.2 +/- 192.2% and +42.6 +/- 137.3%, respectively. The elevation of deltaHX after exercise correlated significantly with the serum concentration of uric acid at rest in untreated hypertensive patients (y = 0.194 - 0.255x; R2 = 0.185, n = 30: P < 0.05). The prevalence of reduction of both deltaHX and serum uric acid was significantly higher in the patients treated with alacepril, bevantolol and doxazosin (67%: P < 0.02) than in the patients treated with losartan, atenolol and manidipine (12%). CONCLUSIONS: It is concluded that the skeletal muscles of hypertensive patients released deltaHX in excess by activation of muscle-type adenosine monophosphate (AMP) deaminase, depending on the degree of hypoxia. The modification of deltaHX by angiotensin-converting enzyme inhibitors and alpha1-blockers influenced the level of serum uric acid, suggesting that the skeletal muscles may be an important source of uric acid as well as of the substrate of xanthine oxidase in hypertension.

AMP Deaminase↗
PubMed2001

[A case of renal cell carcinoma diagnosed by MAG3 scintigraphy because of moderate renal dysfunction].

An 84-year-old man presented at our hospital with complaints of severe gross hematuria and lower right abdominal pain. A right renal mass was detected by ultrasound sonography and plain computerized tomography (CT) scan, but an exact diagnosis was not obtained. Because the patient presented with moderate renal dysfunction and severe gross hematuria, we were unable to perform imaging studies using contrast material or ureteroscopic instruments. Finally, mercaptoacetylglycyl-glycylglycine (MAG3) scintigraphy and magnetic resonance imaging (MRI) demonstrated renal cell carcinoma, and we performed transarterial embolization (TAE) therapy using ethanol and gel foam. Based on their efficacy and noninvasiveness, we conclude that MAG3 scintigraphy and MRI are the optimal modalities for imaging in patients with renal dysfunction.

Aged↗
PubMed2001

[Sclerosing Sertoli cell tumor of the testis: a case report].

We report here a case of sclerosing Sertoli cell tumor of the testis. A 21-year-old male, who complained of right testicular pain, visited a Jikei University affiliated hospital on May 30th, 1999. A small nodule with a diameter of 6 to 7 mm was palpable on the central surface of the right testis. No tumor markers for testicular cancer, such as hCG-beta and alfa-fetoprotein, were elevated. However, ultrasound revealed a hypoechoic mass with increased blood flow. Therefore, we performed right high orchiectomy under the diagnosis of right testicular cancer. Pathological diagnosis of this tumor was sclerosing Sertoli cell tumor. Neither recurrence nor metastasis has been found for 12 months postoperatively.

Adult↗
PubMed2001

[Detection of monoclonal plasma cells in bone marrow and spleen of primary amyloidosis].

A 53-year-old man was diagnosed as primary amyloidosis by biopsy specimens of the mucosa in rectum, spleen and bone marrow (BM). BM examination showed 5.5% of plasma cells with some dysplasia. Immunoglobulin heavy chain gene rearrangement was detected by polymerase chain reaction using third-complementary-determining region (CDR 3) specific primers in BM mononuclear cells and spleen cells embedded in paraffin. The sequence analysis revealed that monoclonal B cells existed in the both, BM and spleen. Flowcytometric analysis using two-color staining showed the phenotype of plasma cells with the expression of CD19+/-, CD27+/-, CD56+/- and CD138+ and CD38++. This phenotype is similar to those of monoclonal gammopathy of undetermined significance (MGUS). Therefore, primary amyloidosis is considered to have two plasma cell populations including normal plasma cells and monoclonal plasma cells in BM. Given that there are two types of plasma cells in patients with primary amyloidosis, amyloid protein is expected to originate from immunoglobulin light chain produced by monoclonal plasma cells.

Amyloid↗
PubMed2000

Hepatocyte growth factor activator inhibitor type 1 is a specific cell surface binding protein of hepatocyte growth factor activator (HGFA) and regulates HGFA activity in the pericellular microenvironment.

Hepatocyte growth factor activator (HGFA) is responsible for proteolytic activation of the precursor form of hepatocyte growth factor in injured tissues. To date, two specific inhibitors of HGFA have been identified, namely HGFA inhibitor type 1 (HAI-1) and type 2 (HAI-2)/placental bikunin (PB). Both inhibitors are first synthesized as integral membrane proteins having two Kunitz domains and a transmembrane domain, and are subsequently released from cell surface by shedding. Here we show that an active form of HGFA is specifically complexed with membrane-form HAI-1, but not with HAI-2/PB, on the surface of epithelial cells expressing both inhibitors. This binding required the enzyme activity of HGFA. The selective binding of HGFA to the cell surface HAI-1 was further confirmed in an engineered system using Chinese hamster ovary cells, in which only the cells expressing HAI-1 retained exogenous HGFA. The binding of HGFA to HAI-1 was reversible, and no irreversible modifications affecting the enzyme activity occurred during the binding. Importantly, HAI-1 and the HGFA.HAI-1 complex were quickly released from the cell surface by treatment with phorbol 12-myristate 13-acetate or interleukin 1beta accompanying the generation of 58-kDa fragments of HAI-1, which are less potent against HGFA, as well as significant recovery of HGFA activity in the culture supernatant. This regulated shedding was completely inhibited by BB3103, a synthetic zinc-metalloproteinase inhibitor. We conclude that HAI-1 is not only an inhibitor but also a specific acceptor of active HGFA, acting as a reservoir of this enzyme on the cell surface. The latter property appears to ensure the concentrated pericellular HGFA activity in certain cellular conditions, such as tissue injury and inflammation, via the up-regulated shedding of HGFA.HAI-1 complex. These findings shed light on a novel function of the integral membrane Kunitz-type inhibitor in the regulation of pericellular proteinase activity.

Animals↗
PubMed2000

A new approach to detect reticulated platelets stained with thiazole orange in thrombocytopenic patients.

Recent studies have shown that reticulated platelets stained with Thiazole Orange (T.O.) are useful markers for thrombopoiesis. The percentage of T.O. positive platelets tends to be inconsistent using the original method, especially when the peripheral blood platelet count is very low. We measured T.O. positive platelet levels in patients with severe thrombocytopenic disorders, using concentrated platelet-rich plasma and carrying out a two-color analysis involving T.O. and an anti-glycoprotein IIb/IIIa monoclonal antibody. This method allowed us to obtain consistent T.O. positive platelet rates in patients with thrombocytopenia whose platelet counts were below 20 approximately 30x10(9)/l. By this method, the T.O. positive rates of platelets from idiopathic thrombocytopenic purpura patients were found to be significantly higher than in the control group. The T.O. positive rates of other thrombocytopenic disorders were similar to those of the control group. These results are consistent with those previously reported. We conclude that our technique of measuring of T.O. positive platelets using platelet-rich plasma is useful for analyzing severe thrombocytopenic disorders.

Benzothiazoles↗
PubMed2000

Visuoperceptual impairment in dementia with Lewy bodies.

BACKGROUND: In dementia with Lewy bodies (DLB), vision-related cognitive and behavioral symptoms are common, and involvement of the occipital visual cortices has been demonstrated in functional neuroimaging studies. OBJECTIVES: To delineate visuoperceptual disturbance in patients with DLB in comparison with that in patients with Alzheimer disease and to explore the relationship between visuoperceptual disturbance and the vision-related cognitive and behavioral symptoms. DESIGN: Case-control study. SETTING: Research-oriented hospital. PATIENTS: Twenty-four patients with probable DLB (based on criteria of the Consortium on DLB International Workshop) and 48 patients with probable Alzheimer disease (based on criteria of the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association) who were matched to those with DLB 2:1 by age, sex, education, and Mini-Mental State Examination score. MAIN OUTCOME MEASURES: Four test items to examine visuoperceptual functions, including the object size discrimination, form discrimination, overlapping figure identification, and visual counting tasks. RESULTS: Compared with patients with probable Alzheimer disease, patients with probable DLB scored significantly lower on all the visuoperceptive tasks (P<.04 to P<.001). In the DLB group, patients with visual hallucinations (n = 18) scored significantly lower on the overlapping figure identification (P = .01) than those without them (n = 6), and patients with television misidentifications (n = 5) scored significantly lower on the size discrimination (P<.001), form discrimination (P = .01), and visual counting (P = .007) than those without them (n = 19). CONCLUSIONS: Visual perception is defective in probable DLB. The defective visual perception plays a role in development of visual hallucinations, delusional misidentifications, visual agnosias, and visuoconstructive disability charcteristic of DLB.

Aged↗