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M Kato

Publications and source records attributed to M Kato.

At least 865 records · Page 48Linked to original sources
PubMed1997

Which relapse criteria best predict the mortality risk of treated alcoholics?

We examined which relapse criteria best predict the mortality risk of treated male alcoholics. The subjects were 172 male alcoholics who had previously been hospitalized. Using three criteria which defined relapse as failure to maintain abstinence from alcohol, alcohol abuse, or dependence, the relapse of each subject had been evaluated during a previous 3-year outcome study. Relative mortality risks in the next 3 years classified by the three relapse criteria were compared. The follow-up rate was 93.6% and 31 subjects died. The age-corrected relative mortality risk for subjects failing to maintain abstinence compared with abstainers was 5.32, while the relative mortality risks for the group abusing alcohol and for the group suffering alcohol dependence were 2.23 and 2.56, respectively. These results suggest that relapse defined as failure to maintain abstinence predicts a higher relative mortality risk than do criteria defining in terms of alcohol abuse and alcohol dependence.

Adult↗
PubMed1997

Elevated expression levels of the 14-3-3 family of proteins in lung cancer tissues.

Immunochemical staining of lung cancer sections with a murine monoclonal anti-14-3-3 antibody showed a sharp discrimination of the cancer tissue from neighboring normal counterparts in 88 of 121 primary lung cancer tissue specimens of all four major lung cancer histologies; specifically, 32 of 48 adenocarcinomas, 36 of 44 squamous cell carcinomas, 10 of 13 large cell carcinomas, and 10 of 16 small cell carcinomas, respectively, were stained positively. Sets of the 10,000 x g supernatants of normal and cancerous lung tissue homogenates, each set prepared from surgically dissected tissues of the cancer and its surrounding normal part, were assayed for 14-3-3 proteins by the sandwich enzyme-linked immunosorbent assay using two different monoclonal antibodies to 14-3-3 proteins. The results of the assay demonstrated 7.2 times higher 14-3-3 protein content in the lung cancer tissue (378 +/- 200 ng ml-1) as compared with the normal lung (54 +/- 35 ng ml-1). These results indicate that the 14-3-3 family of proteins can be an effective marker for lung cancer diagnosis such as sputum cytodiagnosis and that 14-3-3 proteins might be involved in the development of lung cancers.

14-3-3 Proteins↗
PubMed1997

[Mechanism of increase in exercise tolerance in patients with acute myocardial infarction].

The contribution of cardiac output reserve and the skeletal muscle to exercise capacity was investigated in 24 patients with acute myocardial infarction. Symptom-limited exercise tests with a cycle ergometer were performed at 1 week, 3 weeks, and 3 months after the onset of the first infarction. Ventilatory gas was analyzed throughout the testing, and peak oxygen uptake (peak VO2) and anaerobic threshold (AT) were determined. During the test, the cardiac index (CI) was measured by the dye dilution method and the change in CI during exercise (delta CI) was calculated as an index of cardiac output reserve. The cross-sectional area of the thigh muscles (CSA) at the level of 10 cm above the patella was measured using computed tomography. Peak VO2 and AT increased significantly from 1 week to 3 months after the onset of infarction. delta CI increased significantly from 1 week to 3 weeks, and CSA increased significantly from 3 weeks to 3 months. Peak VO2 correlated significantly with both delta CI and CSA at each measurement point, as was AT with delta CI and CSA. Change in peak VO2 correlated with change of delta CI from 1 week to 3 weeks, and also with both delta CI and CSA from 3 weeks to 3 months. These results suggest that both cardiac output reserve and peripheral factors contribute to the exercise capacity up to 3 months after the onset of myocardial infarction. In particular, peripheral factors such as muscle volume are important to improve exercise capacity from 3 weeks to 3 months.

Aged↗
PubMed1997

Possible involvement of nitric oxide in the quinolone-induced tendon lesions in rats.

Quinolone antibacterial agents have been reported to induce adverse effects on the tendon and the musculoskeletal system in humans. We have previously demonstrated that Achilles tendon lesions could be induced in juvenile rats by a single oral administration of quinolones at high doses with simultaneous induction of lesions in the muscle, synovial membrane and articular cartilage. In the present investigation, we examined the involvement of nitric oxide (NO) in pefloxacin (PFLX)-induced lesions of the Achilles tendon in juvenile rats. The incidence of lesions was diminished markedly by co-administration of a potent NO synthase inhibitor, N-nitro-L-arginine methyl ester (L-NAME). Further, the urinary nitrate/nitrite excretion was decreased significantly by 4 h after administration, unchanged between 4 and 8 h, and significantly increased in the 8- to 24-h samples in the PFLX group, as compared to the control group. In contrast, the serum concentration of nitrate/nitrite was significantly higher in the PFLX group 4 h after administration, but there was no difference from controls was observed at 8 and 24 h. These results suggest that NO is involved in the induction of Achilles tendon lesions in juvenile rats by pefloxacin (PFLX) and may be similar to the tendon disorder of humans receiving quinolones.

4-Quinolones↗
PubMed1997

[Functions of the transforming growth factor-beta superfamily in eyes].

One human body is composed of 6 x 10(13) cells, and eyes are also composed of many cells of different functions. The cellular functions and intercellular interaction are regulated by many regulators including cytokines and growth factors to maintain the homeostasis. The transforming growth factor-beta (TGF-beta) superfamily, a large family of multifunctional factors, regulates various cellular functions, including cellular proliferation, migration, differentiation, apoptosis and extracellular matrix production. The TGF-beta superfamily contains about 30 multifunctional factors, and is divided into several families according to the sequence homology. The TGF-beta family, the activin family, and bone morphogenic proteins belong to the TGF-beta superfamily. TGF-beta superfamily members transduce signals through type I and type II serine/threonine type transmembrane receptors. The signals are transduced from receptors through nuclei by Smad family members, which are phosphorylated by the activated type I receptors and translocate from cytoplasm into nuclei. TGF-beta family members and the TGF-beta superfamily receptor family are expressed in ocular tissues including the cornea, ciliary epithelium, lens epithelium, retina, and blood vessels. This observation suggests the importance of the TGF-beta superfamily in eyes. Smad family members (Smad 1, Smad 2, Smad 3 and Smad 4) are expressed in the cultured retinal pigmant epithelial cell line (D407), in which TGF-beta and activin A stimulate the translocation of Smad 2, but not Smad 1 into nuclei, whereas bone morphogenetic protein (BMP) stimulates that of Smad 1, but not Smad 2. TGF-beta superfamily members play important roles in the pathogenesis of retinal neovascularization and in the wound healing process of corneal tissue. TGF-beta inhibits the endothelial functions, but, stimulates angiogenesis in vivo. TGF-beta is involved in the formation of abnormal connective tissue in corneal wound healing. In these processes, many cytokines and growth factors are involved, interacting with each other and forming networks. It is mandatory to clarify the networks to investigate molecular pathogenesis and new therapeutic agents.

Diabetic Retinopathy↗
PubMed1997

[Intubation of a patient with rheumatoid arthritis with a 7.5-mm-ID armored endotracheal tube using a laryngeal mask airway].

A 71-year-old male patient with rheumatoid arthritis was scheduled for posterior fusion of the cervical spine. He showed limited cervical movement and atrophic mandible. Tracheal intubation was difficult in his last anesthetic management for the same surgery. This time, we planned a special procedure for predicted difficult tracheal intubation. After induction of general anesthesia, a size-4 laryngeal mask airway was inserted. Next, a flexible fiberscope sheathed with a 6.0-mm-ID cuffed endotracheal tube was inserted through a laryngeal mask airway into the trachea, and the fiberscope was withdrawn. Then, an endotracheal tube changer was inserted through the endotracheal tube. The laryngeal mask airway and the endotracheal tube were withdrawn simultaneously leaving the tube changer. Finally, a 7.5-mm-ID armored endotracheal tube was inserted through the tube changer. The procedure applied in this case is a safe and reliable intubating method in patients with difficult tracheal intubation.

Aged↗
PubMed1997

Expression of tetra-spans transmembrane family (CD9, CD37, CD53, CD63, CD81 and CD82) in normal and neoplastic human keratinocytes: an association of CD9 with alpha 3 beta 1 integrin.

Tetra-spans transmembrane family (TSTF) members (CD9, CD37, CD53, CD63, CD81 and CD82) have potent effects on cell growth, motility and adhesion in various cells. However, little is known about their expression in human skin. Using immunohistological techniques, we have studied the localization of all six members of TSTF in normal and carcinomatous human keratinocytes. CD9, CD81 and CD82 were expressed in the entire living layers of the epidermis. Their staining pattern was quite similar, and was mainly intercellular with occasional intracellular immunoreactivity. CD53 expression was confined to the intercellular spaces of the upper spinous or granular layer in the normal epidermis. No clear-cut expression of CD63 could be detected in the epidermis. CD37 was not detected at all. Cultured human keratinocytes also expressed CD9, CD81 and CD82 at the surface membrane of cell-cell boundaries. Expression of CD37 and CD53 was negative in cultured keratinocytes, while CD63 was clearly localized in the cytoplasmic lysosomes. An immunoprecipitation assay revealed that alpha 3 beta 1 integrin is molecularly associated with CD9. The expression of CD9, CD81 and CD82 was markedly down-regulated in basal cell carcinoma but not in Bowen's disease. The abundant and differential expression of TSTF molecules and the selective association of CD9 with alpha 3 beta 1 integrin suggest that the TSTF molecules may be involved in the regulation of epidermal differentiation and integrity in vivo.

Antigens, CD↗
PubMed1997

[A study of magnetic stimulation in patients with clinically diagnosed corticobasal degeneration].

Magnetic stimulation (MS) was performed in 9 patients with clinically diagnosed corticobasal degeneration (CBD), 10 patients with Parkinson's disease (PD) (under L-dopa therapy) and 10 age-matched healthy subjects (HS). Motor evoked potentials (MEPs) were recorded from the abductor pollicis brevis muscle (APB) in response to cortical stimulation and cervical stimulation (C7). In all patients with CBD, the duration of inhibitory period (IP), which was a transient suppression of muscle action potentials following MEPs by cortical stimulation, was significantly shorter than that in PD and HS. In 4 patients with CBD who presented with focal and distal myoclonus of one limb, long latency reflexes following electrical stimulation of the median nerve showed C-reflex, which had a latency of about 40 ms, but a giant SEP and a jerk-locked cortical potential were not demonstrated. With cervical MS, these 4 patients also showed long-latency (about 30 ms) evoked potentials (LEPs), which were much greater in latency from cervical stimulation-induced MEPs (cervical MEPs). LEPs may be mediated via a transcortical loop, because the sum of the latency of C-reflex and compound muscle action potential approximates that of LEP and cervical MEP. In patients with CBD, these findings suggest disturbance within the basal ganglia-thalamocortical motor circuit and a damage of the motor cortices including the primary motor cortex, premotor cortex and supplementary motor cortex.

Action Potentials↗
PubMed1997

[Clinical course of patients treated with partial left ventriculectomy].

OBJECTIVE: To assess the efficacy of partial left ventriculectomy as a treatment for patients with end-stage heart failure. METHODS: From February to June 1995, 7 patients with end-stage heart failure underwent partial left ventriculectomy. Subsequently, patients underwent clinical evaluation every 2 months, and 2-dimensional echocardiography at the 6th and 12th months after cardiac surgery. All patients were given digitalis and diuretics at conventional doses, and captopril or enalapril at maximal tolerated doses. RESULTS: Two (28%) patients died; 1 from cardiac arrhythmia associated with gastrointestinal hemorrhage, and the other suddenly. One (14%) patient developed an embolic cerebrovascular accident. Four (57%) patients were hospitalized for congestive heart failure; all of them had either decreased the daily dose of captopril or enalapril or discontinued the drugs by themselves. Twelve months after ventriculectomy, left ventricular ejection fraction values were greater and left ventricular diastolic dimension and functional class values lower than those found before cardiac operation. CONCLUSION: Beneficial effects of partial left ventriculectomy are observed one year after the surgical procedure. This technique, therefore, can be useful for the treatment of patients with end-stage heart failure.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1997

Distribution of free D-amino acids in tissues and body fluids of vertebrates.

Reports on the distribution, metabolism and origins of free D-amino acids in vertebrate tissues and body fluids are reviewed. The transient emergence of D-aspartic acid during the development of brain and peripheral organs or early stages of life is reported. D-Serine in brain is postulated to be a potentiator for the N-methyl-D-aspartate (NMDA) receptor. Some D-amino acid concentrations in human serum, such as D-Ser and D-Ala, are suggested to correlate with damage to renal function.

Alanine↗
PubMed1996

Evidence of a novel redox-linked activation mechanism for the Src kinase which is independent of tyrosine 527-mediated regulation.

The kinase activity of p60c-src has been shown to be basically regulated through phosphorylation and dephosphorylation of Y527. We found that catalytic activity of the immunoprecipitated c-Src kinase from NIH3T3 cells was elevated several folds by exposure to 0.5-50 microM of sulfhydryl-reactive Hg2+. Vmax of the kinase was increased whereas Km was decreased. N-acetylcysteine neutralized this Hg2+ effect, suggesting a critical role of the Hg2+-mediated sulfhydryl modification of the kinase in the mechanism. Addition of protein tyrosine phosphatase inhibitor Na3VO4 into the reaction mixture did not inhibit the Hg2+-mediated activation. Further study revealed that Hg2+ was capable of activating the v-Src kinase lacking Y527 and the c-Src kinase from mutant cells defective of the Y527-phosphorylating Csk kinase. Cyanogen bromide cleavage maps of radiolabeled Src proteins showed that Hg2+ selectively promoted the autophosphorylation at Y416 and that the previously in vivo radiolabeled phosphorous on Y527 was not deleted during the promotion of Y416 autophosphorylation by Hg2+. Phosphoamino acid analysis demonstrated selective promotion of phosphorylation at tyrosine but not at serine/threonine. Not like bivalent Hg2+, monovalent p-chloromercuribenzenesulfonic acid was incapable of activating c-Src kinase. These results suggest a novel Y416 phosphorylation-linked activation pathway for Src kinases which is initially triggered independent of Y527-mediated or serine/threonine phosphorylation-linked regulation, possibly through sulfhydryl-based protein structural modification for functional alteration.

3T3 Cells↗
PubMed1996

Identification and purification of Ca2+/calmodulin-dependent protein kinase V from human gastric carcinoma.

We previously purified a novel Ca2+/calmodulin-dependent protein kinase (CaM kinase) V, which has proven to be a member of the CaM kinase I family. Immunohistochemical staining of surgically-resected specimens from human subjects using specific antibody which reacts with CaM kinases I and V demonstrated heterogeneous distribution of CaM kinase I/V in normal gastric mucosa. The kinase was located mainly at the bottom of foveoral epithelium and in the gastric gland (< 25% immunopositive). In contrast, this kinase was abundant in various types of gastric carcinomas (> 75%), but not in gastric adenomas. Preferential and consistent presence of this kinase was confirmed by immunoblot analysis of gastric carcinoma and human gastric cancer cell lines, Kato-III and MKN-45. CaM kinase I/V was co-purified with CaM kinase II from resected gastric carcinoma using anion-exchange chromatography followed by calmodulin-affinity chromatography. The two kinases were finally separated by HPLC-based gel filtration. Purified CaM kinase I/V from gastric carcinoma did not possess detectable autophosphorylating activity, in contrast to CaM kinase II. The findings suggest CaM kinase I/V may possess abnormal biochemical properties in human gastric carcinoma, and the kinase could participate in cell growth of the carcinoma.

Adenocarcinoma↗
PubMed1996

Physical and functional interaction of rabphilin-3A with alpha-actinin.

Rabphilin-3A is a downstream target molecule of Rab3A small GTP-binding protein and implicated in Ca2+-dependent neurotransmitter release. Here we have isolated a rabphilin-3A-interacting molecule from a human brain cDNA library by the yeast two-hybrid method and identified it to be alpha-actinin, known to cross-link actin filaments into a bundle. alpha-Actinin interacts with the N-terminal region of rabphilin-3A, with which GTP-Rab3A interacts, and this interaction stimulates the activity of alpha-actinin to cross-link actin filaments into a bundle. The interaction of rabphilin-3A with alpha-actinin is inhibited by guanosine 5'-(3-O-thio)triphosphate-Rab3A. These results suggest that the Rab3A-rabphilin-3A system regulates the alpha-actinin-regulated reorganization of actin filaments. It has been shown that reorganization of actin filaments is also involved in Ca2+-dependent exocytosis. Therefore, rabphilin-3A may serve as a linker for Rab3A and cytoskeleton.

Actinin↗
PubMed1996

Immunohistochemical investigation of human leukocyte antigen (HLA)-DR-positive astrocytes in adrenoleukodystrophy brain.

We investigated immunohistochemically the expression of human leukocyte antigen (HLA)-DR in postmortem brain tissue of two adult patients with adrenoleukodystrophy (ALD). In addition to microglia and macrophages, a significant number of star-like cells were stained positively for HLA-DR in demyelinating lesions of both patients. Such cells congregated in the peripheral zone of the lesions. A mirror image analysis as well as double immunostaining for HLA-DR and glial fibrillary acidic protein established that these cells were a subset of reactive astrocytes. Together with other reports demonstrating that astrocytes express HLA-DR only under very limited conditions, the results of this study suggest the involvement of immune and inflammatory responses in the pathological processes of ALD.

Adrenoleukodystrophy↗
PubMed1996

The amino-terminally truncated forms of amyloid beta-protein in brain macrophages in the ischemic lesions of Alzheimer's disease patients.

We have investigated the cerebral cortex of Alzheimer's disease in which small infarcts are found on postmortem neuropathological examination. In areas that have been subjected to recent ischemia, immunohistochemical staining for amyloid beta-protein (A beta) is much less intense than in the non-ischemic surround. However, the infiltrating brain macrophages contain granules immunopositive for C-terminal fragments of A beta. The immunohistochemical profile indicates that A beta in these granules lacks epitopes in the N-terminal fragments. These data suggest that appropriately stimulated macrophages can phagocytose A beta deposits and that digestion of the N-terminal region is an early consequence of this phagocytosis.

Aged↗
PubMed1996

Crystallization and preliminary X-ray analysis of a histidine kinase domain of the anaerobic sensor protein ArcB from Escherichia coli.

Crystals of a novel histidine protein kinase domain of the anaerobic sensor protein ArcB from Escherichia coli have been obtained by a hanging-drop vapor-diffusion method with micro- and macroseeding techniques. Preliminary X-ray crystallographic analysis revealed that they belong to space group P2(1)2(1)2(1) with dimensions a = 30.56, b = 34.93 and c = 110.78 A, having one molecule in the crystallographic asymmetric unit. The crystals diffract to at least 2.0 A resolution.

Journal Article↗
PubMed1996

New graft-implanting method for thoracic aortic aneurysm or dissection with a stented graft.

BACKGROUND: To alleviate the invasiveness of surgical treatment for thoracic aortic aneurysm or dissection involving the distal arch, we developed a new method of implanting a graft in the distal anastomotic portion that does not require dissection, suture, or lateral thoracotomy. METHODS AND RESULTS: The tight circumferential attachment between the graft and the aortic inner wall, produced by the hoop strength of a self-expanding (Gianturco) stent that is anchored into the woven polyester graft, takes the place of the conventional anastomotic suture at the distal end of the graft. This new surgical method requires only a median sternotomy and relatively short circulatory arrest time to repair a thoracic aneurysm or dissection involving the distal arch. In a 12-month period in 1994 and 1995, we applied this new method in 10 cases (seven true aneurysms and three dissections). Complete thrombosis of the aneurysms or false lumens surrounding the grafts resulted in all 10. There were no surgical deaths, and the major complications were two cerebral infarctions due to inappropriate protection of the brain and dissecting procedure of an aortic arch, respectively. CONCLUSIONS: These preliminary results indicate that this new graft-implanting method with the stented graft should be considered one of the less-invasive surgical treatments for thoracic aneurysm and dissection involving the distal arch.

Aged↗