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T Kato

Publications and source records attributed to T Kato.

At least 181 records · Page 10Linked to original sources
PubMed2002

A case of paraneoplastic syndrome accompanied by two types of cancer.

A case of paraneoplastic syndrome accompanied by two types of cancer is reported. The patient was a 62 year old man who progressively developed cerebellar ataxia, especially an abnormal gait. The anti-Hu antibody titre was high. A small tumour was detected in the middle lobe of the right lung and was surgically treated. The histology was adenocarcinoma. After lobectomy, however, the ataxia deteriorated, and plasma exchange, 250 ml/kg/day, was conducted for 6 days. After plasma exchange, the anti-Hu antibody titre decreased and the ataxia temporarily ceased to progress. A week after the last plasma exchange, a mass appeared in the anterior cervical region and rapidly increased in size. The biopsy of the neck tumour disclosed a small cell carcinoma. Five months later small cell carcinoma appeared in the left lung. This case shows the importance of searching for small cell carcinoma when anti-Hu antibodies are detected. It is assumed that plasma exchange removed not only a pathogenic factor of ataxia but also a factor which inhibited the growth of the small cell carcinoma. It is recommended that plasmapheresis should be performed with caution in paraneoplastic syndrome when the origin of a tumour is obscure.

Adenocarcinoma↗
PubMed2002

Brain infarction after percutaneous implantation of port-catheter system via the left subclavian artery.

The aim of this study was to evaluate the incidence of brain infarction after percutaneous implantation of a port-catheter system via the left subclavian artery for hepatic arterial infusion chemotherapy. In 90 patients with inoperable liver cancer, a port-catheter system was implanted via the left subclavian artery. In 5 patients (5.6%) brain infarction occurred after port-catheter implantation. In one patient (1.1%) thrombi formed around the catheter, as confirmed by autopsy. The risk of brain infarction should be taken into consideration when a trans-left subclavian arterial access route is used for the percutaneous implantation of a port-catheter system for hepatic arterial infusion chemotherapy.

Adult↗
PubMed2002

Changes of endothelin in streptozotocin-induced diabetic rats: effects of an angiotensin converting enzyme inhibitor, enalapril maleate.

Endothelin-1 (ET-1) concentrations are increased in patients with diabetes mellitus, particularly those with diabetic retinopathy, or essential hypertension. We hypothesized that ET-1 might participate in the development and progression of diabetic microangiopathy. In this study, the effects of the angiotensin converting enzyme (ACE) inhibitor, enalapril maleate, on diabetic angiopathy were examined in streptozotocin (STZ)-induced diabetic (STZ-DM) rats by monitoring variations in renal function and ET-1 concentrations in blood and organ tissues. Significant increases in kidney weight and in concentrations of urinary albumin, N-acetyl-fl-d-glucosamidase (NAG) and serum ET-1 were observed in the STZ-DM rats as compared with the non-diabetic rats, and the concentration of ET-1 in the kidneys tended to be increased. Microscopic and electron microscopic analyses showed increased mesangial cell proliferation, matrix expansion and enlarged mesangial area in the kidney of the diabetic rats. After administration of the ACE inhibitor, increased concentrations of urinary albumin and NAG in the STZ-DM rats were reduced to the control values with a slight improvement in the electron microscopic changes. These data suggest that ET-1 may be involved in the development and progression of diabetic nephropathy and may explain, in part, why diabetes is liable to complicate hypertension. ACE inhibitor may help to restore diabetic nephropathy in the STZ-induced diabetic rats.

Acetylglucosaminidase↗
PubMed2002

Oropharyngeal airway appliance for infant with upper airway obstruction: report of a case.

A palatal appliance with oropharyngeal tube that reduces the upper airway obstructions of an eleven-month-old male infant with severe cerebral palsy is presented. The palatal appliance was composed of the base plate, the outer guide tube that held the oropharyngeal tube inside it, and the extra outer guide tube for the suction catheter. After the setting of the appliance, respiratory distress was improved without side effects.

Airway Obstruction↗
PubMed2002

Bacterium-based heavy metal biosorbents: enhanced uptake of cadmium by E. coli expressing a metallothionein fused to beta-galactosidase.

We investigated the potential utility of a recombinant E. coli that expresses the human metallothionein II gene as a fusion protein with beta-galactosidase as a heavy metal biosorbent. E. coli cells expressing the metallothionein fusion demonstrated enhanced binding of Cd2+ compared to cells that lack the metallothionein. It was shown that the metallothionein fusion was capable of efficiently removing Cd2+ from solutions. Approximately 40% of the Cd2+ accumulated by the recombinant cells free in suspension was associated with the outer cell membrane, and 60% of that was present in the cytoplasm.

Biodegradation, Environmental↗
PubMed2002

Glucose-6-phosphate dehydrogenase in rat lung alveolar epithelial cells. An ultrastructural enzyme-cytochemical study.

Glucose-6-phosphate dehydrogenase (G6PD) is the key enzyme of the pentose phosphate pathway in carbohydrate metabolism, and it plays an important role in cell proliferation and antioxidant regulation within cells in various organs. Although marked cell proliferation and oxidant/antioxidant metabolism occur in lung alveolar epithelial cells, definite data has been lacking as to whether cytochemically detectable G6PD is present in alveolar epithelial cells. The distribution pattern of G6PD within these cells, if it is present, is also unknown. The purpose of the present study was to investigate the subcellular localization of G6PD in alveolar cells in the rat lung using a newly-developed enzyme-cytochemistry (copper-ferrocyanide) method. Type I cells and stromal endothelia and fibroblasts showed no activities. Electron-dense precipitates indicating G6PD activity were clearly visible in the cytoplasm and on the cytosolic side of the endoplasmic reticulum of type II alveolar epithelial cells. The cytochemical controls ensured specific detection of enzyme activity. This enzyme may play a role in airway defense by delivering substances for cell proliferation and antioxidant forces, thus maintaining the airway architecture.

Animals↗
PubMed2002

Emergent pneumonectomy for hemoptysis in a patient with previous thoracoplasty.

Hemoptysis is a life-threatening episode of respiratory disease. By means of every possible treatment, hemostasis should be obtained to secure the airway as well as to prevent blood loss. We describe an emergency pneumonectomy for massive hemoptysis from destroyed lung in a patient with previous thoracoplasty. After the prolonged ventilation support postoperatively, the patient with compromised lung function recovered well.

Aged↗
PubMed2001

Construction of a genetic linkage map of the model legume Lotus japonicus using an intraspecific F2 population.

Among leguminous plants, the model legume Lotus japonicus (Regel) Larsen has many biological and genetic advantages. We have developed a genetic linkage map of L. japonicus based on amplified fragment length polymorphism (AFLP), simple sequence repeat polymorphism (SSRP) and derived cleaved amplified polymorphic sequence (dCAPS). The F2 mapping population used was derived from a cross between two L. japonicus accessions Gifu B-129 and Miyakojima MG-20. These parental accessions showed remarkable cytological differences, particularly with respect to size and morphology of chromosomes 1 and 2. Using fluorescence in situ hybridization (FISH) with BAC clones from Gifu B-129 and TAC (Transformation-competent Artificial Chromosome) clones from Miyakojima MG-20, a reciprocal translocation was found to be responsible for the cytological differences between chromosomes 1 and 2. The borders of the translocations were identified by FISH and by alignment toward the L. filicaulis x L. japonicus Gifu B-129 linkage map. The markers from the main translocated region were located on linkage groups 1 and 2 of the two accessions, Gifu B-129 and Miyakojima MG-20, respectively. The framework of the linkage map was constructed based on codominant markers, and then dominant markers were integrated separately in each linkage group of the parents. The resulting linkage groups correspond to the six pairs of chromosomes of L. japonicus and consist of 287 markers with 487.3 cM length in Gifu B-129 and 277 markers with 481.6 cM length in Miyakojima MG-20. The map and marker information is available through the World Wide Web at http://www.kazusa.or.jp/lotus/.

Chromosome Mapping↗
PubMed2001

Structural analysis of a Lotus japonicus genome. I. Sequence features and mapping of fifty-six TAC clones which cover the 5.4 mb regions of the genome.

A total of 56 TAC clones with an average insert size of 100 kb were isolated from a TAC library of the Lotus japonicus genome based on the expressed sequences tags (ESTs), cDNA and gene information, and their nucleotide sequences were determined according to the shot-gun based strategy. The total length of the sequenced regions is 5,473,195 bp. By comparison with the sequences in protein and EST databases and analysis with computer programs for gene modeling, a total of 605 potential protein-encoding genes with known or predicted functions, 69 gene segments, and 172 pseudogenes were identified. The average density of the genes assigned so far is 1 gene/8120 bp. Introns were identified in approximately 78% of the potential genes. There was an average of 3.8 introns per gene and the average length of the introns was 375 bp. DNA markers were generated based on the nucleotide sequences obtained, and each clone was mapped onto the linkage map using the F2 mapping population derived from a cross of L. japonicus Gifu B-129 and Miyakojima MG-20. The sequence data, gene information and mapping information are available through the World Wide Web at http://www.kazusa.or.jp/lotus/.

Base Sequence↗
PubMed2001

Chronic effects of the nucleus pulposus applied to nerve roots on ectopic firing and conduction velocity.

STUDY DESIGN: This study analyzed the effects of the autologous nucleus pulposus (NP) on nerve root function using electrophysiologic methods. OBJECTIVES: To investigate the chronic effects of the NP applied to nerve roots and dorsal root ganglions (DRGs) on ectopic firing and nerve conduction velocity. SUMMARY OF BACKGROUND DATA: It was reported that ectopic firing in DRGs is involved in abnormal sensation such as sciatica and that ectopic firing was increased shortly after application of the NP to nerve roots. It was also reported that various inflammatory reactions occur around herniated NP clinically, which may affect nerve roots. However, the chronic action of NP on ectopic firing in the stage of inflammatory reaction is unknown. METHODS: Forty-six rats were divided into three groups: nucleus pulposus (NP) group, sham group, and control group. In the NP group the autologous NP was applied to L4 and L5 nerve roots. At 1, 2, 4, and 8 weeks after treatment, antidromically propagated ectopic firing from nerve roots was recorded from the sural nerve, and the nerve conduction velocity between the cauda equina and sciatic nerve was analyzed. The frequencies of ectopic firing in the three groups were compared. The ratios of the nerve conduction velocities on the treatment side and opposite side were compared between the NP and sham groups. RESULTS: The frequency was significantly higher in the NP group than in the sham group at 4 weeks. There were no significant differences among the three groups at 8 weeks. There was no significant difference in the treatment side/opposite side ratio of nerve conduction velocity between the NP and sham groups at any time point. CONCLUSIONS: Increased ectopic firing in the stage of inflammatory reaction to NP may be related to abnormal sensation.

Animals↗
PubMed2001

Candesartan inhibits carotid intimal thickening and ameliorates insulin resistance in balloon-injured diabetic rats.

This study investigates the effects of candesartan, an angiotensin II type 1 receptor blockade, on carotid arterial intimal thickening and glucose tolerance in balloon-injured male Wistar fatty rats and their littermates (Wistar lean rats). Candesartan was orally administered to 12-week-old rats for 21 days, and age-matched rats without the agent were used as the respective controls. Balloon catheterization in the left common carotid artery was performed on day 7, and the artery was removed on day 14 for histological analysis. Compared with the area ratios of the neointima/media in fatty rats without treatment, the ratios in fatty rats treated with candesartan at 1 mg. kg(-1). d(-1) and lean rats without treatment were significantly decreased to 65%; on the other hand, the ratios of fatty rats treated with candesartan at 10 mg. kg(-1). d(-1) and lean rats treated with 1 mg. kg(-1). d(-1) were reduced to 35%, and those of lean rats treated with 10 mg. kg(-1). d(-1) were reduced to 28%. The administration of candesartan also decreased the level of plasma glucose time- and dose-dependently in fatty rats. In an intragastric glucose load, the levels of both glucose and insulin at 30 and 60 minutes were significantly decreased when fatty rats were treated with candesartan at 10 mg. kg(-1). d(-1). In cultured vascular smooth muscle cells from fatty rats, insulin-stimulated Akt (New England Biolabs) phosphorylation and 2-deoxy-D-glucose uptake were inhibited to 59% and 68%, respectively, by angiotensin II, but the effects were ameliorated by the addition of 10(-7) mol/L candesartan. We conclude that candesartan could be effective for the suppression of vascular smooth muscle cell growth dose-dependently in Wistar fatty and lean rats. Furthermore, the agent could improve insulin resistance in Wistar fatty rats.

Angiotensin Receptor Antagonists↗
PubMed2001

Diminished corneal angiogenesis in gelatinase A-deficient mice.

The goal of the present study was to define the role of gelatinase A in angiogenesis. We performed corneal micropocket assays in gelatinase A-deficient mice and their age-matched wild-type littermates. The corneal neovascular area in gelatinase A-deficient mice (0.15+/-0.14 mm(2)) was significantly less than that of wild-type littermates (0.53+/-0.35 mm(2); P<0.01). Similarly, aortic ring assays showed significant reduction of endothelial outgrowth in gelatinase A-deficient mice (0.26+/-0.14 mm(2)) as compared to wild-type littermates (0.44+/-0.06 mm(2); P<0.05). These results suggest that gelatinase A may play an important role in the regulation of corneal angiogenesis.

Animals↗
PubMed2001

Aqua[N-(6-carboxylato-kappa O-pyridine-2-carbonyl-kappa N)-L-histidinato-kappa(2)N,N']copper(II).

The title compound, [Cu(C(13)H(10)N(4)O(5))(H(2)O)], is an asymmetric and pentacoordinated square-pyramidal copper(II) complex, with a water molecule occupying an apical position. It consists of syn and anti isomers of the apical water molecule with respect to the metal-free carboxyl group on the equatorial ligand. The crystal structure of this complex is a rare example of conformational isomerization, in which the two isomers cocrystallize in a 1:3 ratio of syn to anti molecules in the same lattice.

Journal Article↗
PubMed2001

Actinobacillus actinomycetemcomitans possesses an antigen binding to anti-human IL-10 antibody.

It is well known that the cell components of periodontopathic bacteria are able to induce several cytokines and possibly to affect the cytokine network. In order to determine the presence of the periodontopathic Actinobacillus actinomycetemcomitans components recognized by antibodies against cytokine molecules, ELISA reactivities of sonic extracts from the bacterial cells were determined by use of ELISA kits specific for human interleukin (IL)-1beta, IL-4, IL-5, IL-6, IL-10, tumor necrosis factor-alpha, and interferon-gamma. The ELISA analysis demonstrated that the sonic extracts from eight strains of A. actinomycetemcomitans bound with anti-human IL-10 monoclonal antibody. Western blotting analysis revealed that the molecular mass of the antigen was approximately 65 kDa. IL-10 is produced by type 2 helper T cells and mainly down-regulates the type 1 helper T cell response. The present study suggests that the 65-kDa antigen of A. actinomycetemcomitans may affect the host defense function through binding to IL-10 receptor as an agonist or an antagonist for IL-10.

Aggregatibacter actinomycetemcomitans↗
PubMed2001

Epidermal growth factor down-regulates connexin-43 expression in cultured rat cortical astrocytes.

Astrocytes are coupled via gap junction channels, predominantly formed by connexin-43 (Cx43), and contribute to neuronal function in the normal and diseased brain. In this study, we demonstrate that epidermal growth factor (EGF), applied to cortical astrocytes, results in a decrease in the expression of Cx43 mRNA and protein. We have further shown that the decrease is associated with the receptor tyrosine kinase pathway and the MEK inhibitor prevents EGF-stimulated down-regulation of Cx43 expression. These findings demonstrate a previously unknown function of EGF on cultured astrocytes, which may be relevant to the regulation of astrocytic growth and differentiation.

Animals↗
PubMed2001

Expression of glia maturation factor during retinal development in the rat.

Glia maturation factor plays important roles in the development and growth of glia and neurons. We investigated the expression and localization of Glia maturation factor-beta (GMFB) and Glia maturation factor-gamma (GMFG) in the rat retina. By northern blot analysis, both GMFB and GMFG mRNAs were detected in retina as early as embryonic day (E) 18 and persisted until adult. The expression of GMFB mRNA was always much greater than that of GMFG mRNA. In situ hybridization showed that the GMFB mRNA signal was positive in the retina from E14 till adult. Immunostaining revealed that GMFB protein was present in the inner layer of retina at E14 and P1, and in Müller cells in adult. GMFG immunoreactivity was observed only in the inner limiting membrane from E14 to P1 rat retina, and was not detected in the adult retina. These results show that GMFs are synthesized and localized mainly in Müller cells in the rat retina, and suggest that they may contribute to the development and growth of glia and neurons.

Animals↗
PubMed2001

Potassium channel blocker activates extracellular signal-regulated kinases through Pyk2 and epidermal growth factor receptor in rat cardiomyocytes.

OBJECTIVES: We sought to determine whether potassium (K(+)) channel blockers (KBs) can activate extracellular signal-regulated kinase (ERK) and to characterize the upstream signals leading to ERK activation in cardiomyocytes. BACKGROUND: Because KBs attenuate K(+) outward current, they may possibly prolong the duration of action potentials, leading to an increase in calcium (Ca(2+)) transient ([Ca(2+)](i)) in cardiomyocytes. Elevation of intracellular Ca(2+) levels can trigger various signaling events. Influx of Ca(2+) through L-type Ca(2+) channels after membrane depolarization induced activation of MEK and ERK through activation of Ras in neurons. Although KBs are frequently used to treat cardiac arrhythmias, their effect on signaling pathways remains unknown. METHODS: Primary cultured rat cardiomyocytes were stimulated with four different KBs-4-aminopyridine (4-AP), E-4031, tetra-ethylammonium and quinidine-and phosphorylation of ERK, proline-rich tyrosine kinase 2 (Pyk2) and epidermal growth factor receptor (EGFR) was detected. Action potentials were recorded by use of a conventional microelectrode. (Ca(2+))(i) was monitored by the fluorescent calcium indicator Fluo-4. RESULTS: E-4031, 4-AP, tetra-ethylammonium and quinidine induced phosphorylation of ERK. 4-Aminopyridine prolonged the duration of action potentials by 37% and increased (Ca(2+))(i) by 52% at 1 mmol/l. Pre-incubation of ethyleneglycoltetraacetic acid, 1,2-bis(2-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid tetrakis and diltiazem completely blocked this phosphorylation, whereas flufenamic acid and benzamil did not. 4-Aminopyridine induced tyrosine phosphorylation of Pyk2 and EGFR, which peaked at 5 and 10 min, respectively. Cytochalasin D, AG1478 and dominant-negative EGFR strongly inhibited the phosphorylation of ERK, whereas calphostin C, calmidazolium and KN62 did not. CONCLUSIONS: These findings indicate that KBs induce ERK activation, which starts with Ca(2+) entry through the L-type Ca(2+) channel in cardiomyocytes, and that EGFR and Pyk2 are involved in this activation.

4-Aminopyridine↗