1926
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Mukai M, Ikeda M, Yanagihara T, Hara G, Kato K, Ishiguro K, Nakagaki H, Robinson C. Fluoride distribution in dentine and cementum in human permanent teeth with vital and non-vital pulps. Arch Oral Biol 1994; 39:191-6. [PMID: 8018051 DOI: 10.1016/0003-9969(94)90044-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Twenty-two selected permanent teeth [11 with vital pulps and 11 with non-vital (necrotic) pulps] were obtained from patients aged from 20 to 73 yr in Nagoya, Japan. Fluoride (F) profiles in tooth samples were examined by using an abrasive micro-sampling technique. F levels in the pulpal dentine were significantly higher in vital than non-vital teeth for each age group, although there were observed increases of F with age. In the cementum the F levels were strongly related to age and there were few differences in profiles and levels of F between vital and non-vital teeth. It was concluded that vital pulp is an important factor for the pulpal dentine to absorb fluoride.
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1927
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Soga T, Shirai A, Igarashi T, Kato K, Ishigatsubo Y, Okubo T. [A case of Listeria meningitis associated with systemic lupus erythematosus]. KANSENSHOGAKU ZASSHI. THE JOURNAL OF THE JAPANESE ASSOCIATION FOR INFECTIOUS DISEASES 1994; 68:411-5. [PMID: 8176284 DOI: 10.11150/kansenshogakuzasshi1970.68.411] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We report a case of Listeria meningitis associated with systemic lupus erythematosus (SLE). The case is a 29-year-old female who was diagnosed as SLE on August, 1982, and had been followed since then. On May 25, 1993, she was admitted to our hospital with complaints of fever, head ache and vomiting which developed 3 days before admission. An examination of the cerebro-spinal fluid (CSF) revealed a cell count of (3664/3/mm3), protein concentration (123 mg/dl), and the quotient of CSF (Q albumin) (27.5) were elevated. A diagnosis of meningitis was made and therapy of antibiotics was begun. A CSF culture on admission was positive for Listeria monocytogenes, but the blood culture was negative. Clinical symptoms disappeared in about a week and abnormal CSF findings returned to normal in about a month with the administration of antibiotics. Listeria infection is a rare disease, but sometimes develops as an opportunistic infection in immunocompromised hosts. As far as we know, only 13 cases have been reported so far (9 cases in foreign countries, 4 cases in Japan). We also discuss Listeria infections associsted with SLE referring to the former reports.
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1928
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Kato K, Matsubara T, Sakamoto N. Correlation between myocardial blood flow and tissue succinate during acute ischemia. NAGOYA JOURNAL OF MEDICAL SCIENCE 1994; 57:43-50. [PMID: 7898561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This study was performed to clarify the relationship between degree plus duration of myocardial ischemia and tissue succinate or lactate contents, and to assess whether their accumulation might be a metabolic marker of ischemic myocardium. Regional myocardial blood flow (MBF) was measured using the hydrogen gas clearance method in anesthetized open-chest dogs subjected to 10 min or 60 min of myocardial ischemia by coronary ligation. The contents of succinic acid and lactic acid in myocardium corresponding to locations of MBF measurement were quantitatively analyzed by gas chromatography-mass spectrometry. In severely ischemic areas with MBF less than 20 ml/min/100g, significant increases in both succinic and lactic acids were observed 10 min after coronary occlusion. Sixty min of ischemia induced significant increase in the myocardial succinic acid content not only in severely but also in moderately ischemic areas. In contrast, lactic acid was significantly increased only in the severely ischemic area 60 min after coronary occlusion. These results indicate a good correlation between degree plus duration of myocardial ischemia and tissue succinic acid content, suggesting that its accumulation in myocardium may be a reliable and sensitive metabolic marker of coronary ligation ischemia.
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1929
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Kim H, Matsunaga C, Yoshino A, Kato K, Arata Y. Dynamical structure of the hinge region of immunoglobulin G as studied by 13C nuclear magnetic resonance spectroscopy. J Mol Biol 1994; 236:300-9. [PMID: 8107111 DOI: 10.1006/jmbi.1994.1136] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The segmental flexibility of the hinge region of immunoglobulin G (IgG) molecules has been considered to play important roles in the mediation between antigen recognition and effector functions. Here we report the result of a 13C nuclear magnetic resonance study of the dynamical structure of the hinge region of a mouse monoclonal IgG2a antibody. In the present work, a variety of IgG2a analogs selectively labeled with 13C at the carbonyl carbon atom were prepared. The flexibility of the hinge region was discussed on the basis of the linewidth data of 13C resonances obtained using a Carr-Purcell-Meiboom-Gill pulse train. It was concluded that the hinge region of the mouse IgG2a molecule has a mosaic structure with heterogeneous nature of flexibility with the rigid core part flanked by upper and lower hinges, which are highly flexible peptide segments. Cleavage of the inter-chain disulfide bridges led to homogeneous flexibility of the hinge region, except for the N-terminal side of the upper hinge. It was suggested that the rigidity in the N-terminal side of the upper hinge is due to the interaction with the CH1 domain. Biological significance of the mosaic structure of the hinge region was briefly discussed.
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1930
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Kato K, Ohtsuki K, Mitsuda H, Yomo T, Negoro S, Urabe I. Insertion sequence IS6100 on plasmid pOAD2, which degrades nylon oligomers. J Bacteriol 1994; 176:1197-200. [PMID: 8106333 PMCID: PMC205175 DOI: 10.1128/jb.176.4.1197-1200.1994] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The nucleotide sequence of repeated sequence I, which appears in five regions on nylon oligomer-degrading plasmid pOAD2, harbored in Flavobacterium sp. strain K172, was determined. The five regions of repeated sequence I had 880 bp of identical sequence, and the sequence was identical to that of IS6100, an insertion sequence classified in the IS6 family, initially found in Mycobacterium fortuitum. Sequences homologous to that of IS6100 were found for another nylon oligomer-degrading plasmid, pNAD2, harbored in Pseudomonas sp. strain NK87, by Southern hybridization experiments.
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1931
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Isaji S, Kato K, Tanigawa K. [Diagnosis and surgical treatment for endocrine tumors of the pancreas]. RINSHO BYORI. THE JAPANESE JOURNAL OF CLINICAL PATHOLOGY 1994; 42:150-9. [PMID: 8139124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Clinical features, diagnostic accuracy of imaging study, and the outcome of surgical treatment for endocrine tumors of the pancreas were analyzed in 12 patients who underwent surgery for the past 16 years and 11 months. The 12 cases were classified into two groups: functioning tumors in 8 (insulinoma in 7 including one malignant case, and malignant glucagonoma in one), and nonfunctioning tumors in 4 including 3 malignant cases. In functioning tumors, tumor size was 2 cm or less in 6 benign cases, but 5 cm or more in 2 malignant cases. In nonfunctioning tumors, tumor size was larger, ranging from 3.5 to 8.0 cm. Diagnostic accuracy for localization of functioning tumors was 66.7% for US, 75.0% for CT, 66.7% for endoscopic retrograde pancreatography (ERP), and 50.0% for selective angiography, while all nonfunctioning tumors could be detected by any diagnostic imagings. Percutaneous transhepatic portal venous sampling for immunoreactive insulin was very helpful to localize insulinoma. Stenosis or obstruction of the main pancreatic duct on ERP and arterial encasement on angiography highly suggested a malignant tumor. Even for malignant cases with liver metastasis, resection of the primary tumor with debulking of metastatic disease or intraarterial infusion chemotherapy was considered to prolong patient prognosis.
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1932
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Quilliam LA, Kato K, Rabun KM, Hisaka MM, Huff SY, Campbell-Burk S, Der CJ. Identification of residues critical for Ras(17N) growth-inhibitory phenotype and for Ras interaction with guanine nucleotide exchange factors. Mol Cell Biol 1994; 14:1113-21. [PMID: 8289792 PMCID: PMC358467 DOI: 10.1128/mcb.14.2.1113-1121.1994] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The Ras(17N) dominant negative antagonizes endogenous Ras function by forming stable, inactive complexes with Ras guanine nucleotide exchange factors (GEFs; e.g., SOS1). We have used the growth-inhibitory phenotype of Ras(17N) to characterize two aspects of Ras interaction with GEFs. First, we used a nonprenylated version of Ras(17N), designated Ras(17N/186S), which no longer associates with the plasma membrane and lacks the growth-inhibitory phenotype, to address the importance of Ras subcellular location and posttranslational modification for its interaction with GEFs. We observed that addition of an N-terminal myristylation signal to Ras(17N/186S) restored the growth-inhibitory activity of nonprenylated Ras(17N). Thus, membrane association, rather than prenylation, is critical for Ras interaction with Ras GEFs. Second, we used a biological selection approach to identify Ras residues which are critical for Ras(17N) growth inhibition and hence for interaction with Ras GEFs. We identified mutations at residues 75, 76, and 78 that abolished the growth-inhibitory activity of Ras(17N). Since GEF interaction is dispensable for oncogenic but not normal Ras function, our demonstration that single-amino-acid substitutions at these three positions impaired the transforming activity of normal but not oncogenic Ras provides further support for the role of these residues in Ras-GEF interactions. Finally, Ras(WT) proteins with mutations at these residues were no longer activated by mammalian SOS1. Altogether, these results suggest that the Ras intracellular location and Ras residues 75 to 78 are critical for Ras-GEF interaction.
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1933
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Deguchi J, Yamamoto A, Yoshimori T, Sugasawa K, Moriyama Y, Futai M, Suzuki T, Kato K, Uyama M, Tashiro Y. Acidification of phagosomes and degradation of rod outer segments in rat retinal pigment epithelium. Invest Ophthalmol Vis Sci 1994; 35:568-79. [PMID: 8113008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
PURPOSE The authors investigated the phagocytic processes of the rod outer segments (ROS) in rat retinal pigment epithelium (RPE) cells, and the appearance of lysosomal enzymes, acidification, and degradation of the contents in the phagolysosomes. In particular, they examined the effect of bafilomycin A1, a specific inhibitor of vacuolar-type H(+)-ATPase, on the degradation of ROS in the RPE cells in vivo. METHODS A lysosomal enzyme (cathepsin D), a lysosomal membrane protein (LGP107), and opsin were localized in the RPE cells by the immunogold electron microscopic technique. Bafilomycin A1 was injected into the vitreous, and acidification of the phagosomes was measured in vivo by injecting 3-[2,4-dinitroanilino]3'amino-N-methyldipropylamine (DAMP) in the vitreous and detecting the accumulation of DAMP in the phagolysosomes using anti-dinitrophenol antibody. RESULTS Opsin was abundantly detected in phagosomes that did not contain cathepsin D, but the immunolabeling of opsin rapidly disappeared soon after the appearance of cathepsin D. By double staining with cathepsin D and DAMP, it was shown that the pH of the phagosomes dramatically decreased after fusion with lysosomes. When bafilomycin A1 was injected into the vitreous, many large phagolysosomes containing cathepsin D appeared in the RPE cells, in which the immunoreactivity of opsin was well preserved. CONCLUSIONS Degradation of opsin and acidification proceeded almost parallel with the appearance of cathepsin D in the phagolysosomes. Bafilomycin A1 did not inhibit the fusion of phagosomes with lysosomes, but it increased intraphagosomal pH and markedly inhibited the degradation of ROS in the phagolysosomes. This result indicates that vacuolar-type H(+)-ATPase is essential for acidifying the lumen of phagolysosomes and subsequent protein degradation of ROS in the RPE cells.
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1934
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Jones MH, Koi S, Fujimoto I, Hasumi K, Kato K, Nakamura Y. Allelotype of uterine cancer by analysis of RFLP and microsatellite polymorphisms: frequent loss of heterozygosity on chromosome arms 3p, 9q, 10q, and 17p. Genes Chromosomes Cancer 1994; 9:119-23. [PMID: 7513541 DOI: 10.1002/gcc.2870090207] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Cancers in which mutations have been identified in putative tumor suppressor genes, such as the TP53 gene, the retinoblastoma (RBI) gene, the adenomatous polyposis coli (APC) gene, and the Wilms tumor (WTI) gene, frequently show loss of the corresponding allele on the homologous chromosome. To identify locations of tumor suppressor genes involved in uterine cancer, we examined loss of heterozygosity (LOH) by using genomic probes detecting RFLPs in 35 uterine cancers at 29 loci throughout the genome, and with highly informative microsatellite markers in 21 uterine cancers at nine putative or known tumor suppressor gene loci. High frequencies of allelic loss found at loci on 3p (71%), 9q (38%), 10q (35%), and 17p (35%) suggest that tumor suppressor genes involved in uterine carcinogenesis exist in these regions. There were no significant differences in frequencies of LOH between cancers of the uterine cervix and cancers of the uterine endometrium at any of the loci tested.
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MESH Headings
- Adenocarcinoma/genetics
- Adenocarcinoma/pathology
- Alleles
- Base Sequence
- Carcinoma, Squamous Cell/genetics
- Carcinoma, Squamous Cell/pathology
- Chromosome Aberrations
- Chromosomes, Human, Pair 10/ultrastructure
- Chromosomes, Human, Pair 17/ultrastructure
- Chromosomes, Human, Pair 3/ultrastructure
- Chromosomes, Human, Pair 9/ultrastructure
- DNA, Neoplasm/genetics
- DNA, Satellite/genetics
- Endometrial Neoplasms/genetics
- Endometrial Neoplasms/pathology
- Female
- Genes, Tumor Suppressor
- Heterozygote
- Humans
- Lymphatic Metastasis/genetics
- Polymorphism, Genetic
- Polymorphism, Restriction Fragment Length
- Repetitive Sequences, Nucleic Acid
- Sequence Deletion
- Uterine Cervical Neoplasms/genetics
- Uterine Cervical Neoplasms/pathology
- Uterine Neoplasms/genetics
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1935
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Kato H, Liu Y, Kogure K, Kato K. Induction of 27-kDa heat shock protein following cerebral ischemia in a rat model of ischemic tolerance. Brain Res 1994; 634:235-44. [PMID: 8131073 DOI: 10.1016/0006-8993(94)91926-7] [Citation(s) in RCA: 139] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Preconditioning the brain with sublethal cerebral ischemia induces tolerance to subsequent lethal periods of ischemia (ischemic tolerance). The purpose of this study is to investigate the role of low-molecular weight stress proteins, 27-kDa heat shock protein (HSP27) and alpha B crystallin, in ischemic tolerance. We measured the content of these proteins with enzyme immunoassay in the rat hippocampus and cerebral cortex following 6 min of ischemia with and without preconditioning with 3 min of ischemia and 3 days of reperfusion. We also visualized the localization of HSP27 immunohistochemically in comparison with that of HSP70. A 3-min period of ischemia caused a 2.4-fold increase in HSP27 content in the hippocampus after 3 days. Immunohistochemical localization of HSP27 was found in glial cells in all subregions of the hippocampus, whereas HSP70 immunostaining was seen only in CA1 pyramidal neurons. HSP27 content in the hippocampus decreased 2 h after 6 min of ischemia. HSP27 content progressively increased in the unpreconditioned hippocampus after 1 and 3 days, but returned to preischemic levels in the preconditioned hippocampus. HSP27 and HSP70 immunostaining was seen in CA1 pyramidal neurons after 1 day both with and without preconditioning. After 3 and 7 days, an intense HSP27 staining was observed in reactive glial cells in the CA1 without preconditioning, whereas the staining decreased in the preconditioned hippocampus. HSP70 staining was seen only in neurons at these time points. We observed no significant changes in HSP27 content in the cerebral cortex although neurons in the third and fifth layers were immunostained after 1 and 3 days. We observed no alterations in alpha B crystallin content after ischemia both in the hippocampus and the cortex. The present study demonstrated that cerebral ischemia induces HSP27 expression but not alpha B crystallin. Both HSP27 and HSP70 induction had a good temporal correlation with the induction of ischemic tolerance. However, different sites of action were suggested because the localization and cell types of HSP27 induction were quite different from those of HSP70 induction. The result suggests that it is unlikely that HSP27 is directly involved in the protection afforded by ischemic preconditioning.
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1936
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Kato K, Clark GD, Bazan NG, Zorumski CF. Platelet-activating factor as a potential retrograde messenger in CA1 hippocampal long-term potentiation. Nature 1994; 367:175-9. [PMID: 8114914 DOI: 10.1038/367175a0] [Citation(s) in RCA: 211] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Long-term potentiation (LTP) refers to a persisting enhancement of neurotransmission that follows high-frequency activation of certain synapses. Although both pre- and postsynaptic mechanisms contribute to LTP, it is believed that the enhanced release of neurotransmitter that accompanies this process results from the production of a diffusible messenger in postsynaptic neurons which traverses the synaptic cleft and alters the function of presynaptic terminals. One candidate for such a messenger is arachidonic acid, a metabolite produced by phospholipase A2 which augments synaptic transmission when coupled with presynaptic stimulation. However, the effects of arachidonic acid require activation of the postsynaptic receptor for N-methyl-D-aspartate. Previously we found that platelet-activating factor (1 O-alkyl-2-acetyl-sn-glycero-3-phosphocholine), another phospholipase A2-derived messenger, selectively enhances excitatory postsynaptic currents in hippocampal neurons by a presynaptic mechanism. We now present evidence that platelet-activating factor, acting at a receptor localized to synaptic regions, participates in LTP in the CA1 region of rat hippocampal slices and may serve as part of a retrograde signalling cascade.
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1937
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Morishita R, Kato K, Asano T. A brain-specific gamma subunit of G protein freed from the corresponding beta subunit under non-denaturing conditions. FEBS Lett 1994; 337:23-6. [PMID: 8276106 DOI: 10.1016/0014-5793(94)80622-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
It has generally been accepted that the beta and gamma subunits of G proteins are tightly associated and can only be dissociated under denaturing conditions. However, one form of the gamma subunit, free of the beta subunit, was isolated under non-denaturing conditions during the purification of beta gamma complexes from bovine brain. Amino acid sequence analysis revealed that the N-terminus of this gamma subunit was not blocked and its sequence was identical to that of a brain-specific gamma subunit, gamma 3. Among three forms of gamma subunits observed in bovine brain (gamma 2, gamma 3 and gamma 7), gamma 3 was the only form that was not modified at the N-terminus. Although the physiological significance of the free form of gamma 3 is not clear, these results suggest that N-terminal modification of gamma subunits may be important for interaction with beta subunits.
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1938
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1939
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Arata Y, Kato K, Takahashi H, Shimada I. Nuclear magnetic resonance study of antibodies: a multinuclear approach. Methods Enzymol 1994; 239:440-64. [PMID: 7830594 DOI: 10.1016/s0076-6879(94)39017-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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1940
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Yamagiwa S, Niwa K, Yokoyama Y, Tanaka T, Murase T, Shimonaka E, Shimokawa K, Kato K, Tamaya T. Primary adenoid cystic carcinoma of Bartholin's gland. A case report. Acta Cytol 1994; 38:79-82. [PMID: 8291360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
An extremely rare case of primary adenoid cystic carcinoma of Bartholin's gland in a 71-year-old woman is reported. With the working diagnosis of malignancy of Bartholin's gland on biopsy, she underwent a left radical vulvectomy with bilateral inguinal and pelvic lymphadenectomy and postoperative left vulvar irradiation. The cytologic and pathologic findings on the surgical specimens were distinctive. The imprint cytology of the cut surface of the tumor showed that the neoplastic cells were crowded and that some cells had a peripherally displaced nucleus. The nuclei were oval or round, and the quantity of chromatin was increased and fine. Some nuclei had prominent nucleoli. The cytoplasm was abundant. The surgical specimens showed the same findings as did cytology. the final diagnosis was primary adenoid cystic carcinoma of Bartholin's gland, postoperatively based on the cytologic and pathologic findings.
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1941
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Taché Y, Yoneda M, Kato K, Király A, Sütö G, Kaneko H. Intracisternal thyrotropin-releasing hormone-induced vagally mediated gastric protection against ethanol lesions: central and peripheral mechanisms. J Gastroenterol Hepatol 1994; 9 Suppl 1:S29-35. [PMID: 7881015 DOI: 10.1111/j.1440-1746.1994.tb01298.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The vagus is involved in mediating gastric cytoprotection and adaptive cytoprotection. However, the central and peripheral mechanisms through which the vagus expresses its action are still poorly known. Medullary thyrotropin-releasing hormone (TRH) plays an important role in the vagal regulation of gastric function. The stable TRH analogue, RX 77368, micro-injected into the cisterna magna or the dorsal motor nucleus (DMN) of the vagus at a dose that did not influence gastric acid secretion prevented gastric injury induced by intragastric administration of 60% ethanol in conscious or urethane-anaesthetized rats. The cytoprotective action of TRH is mediated through vagal cholinergic release of prostaglandin E2 (PGE2). Prostaglandin E2 action is unrelated to changes in gastric mucosal blood flow (GMBF). In addition, other peripheral mechanisms involve calcitonin gene-related peptide (CGRP) contained in capsaicin sensitive afferent fibres and nitric oxide, both of which mediate the associated increase in GMBF induced by intracisternal injection of RX 77368. These data indicate that medullary TRH induces vagally mediated gastric protection against ethanol lesions. Its action is expressed through the muscarinic dependent release of PGE2 and nitric oxide, and efferent function of capsaicin-sensitive afferent fibres releasing CGRP.
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1942
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Kokeguchi S, Miyamoto M, Kato K, Tanimoto I, Kurihara H, Murayama Y. Isolation and characterization of a 53 kDa major cell envelope protein antigen from Treponema denticola ATCC 35405. J Periodontal Res 1994; 29:70-8. [PMID: 8113954 DOI: 10.1111/j.1600-0765.1994.tb01093.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A major cell envelope protein was purified from the cell envelope fraction of Treponema denticola ATCC 35405 by ion exchange chromatography after extraction with Zwittergent 3-14. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a relative molecular mass of 53 kDa for this protein with a pI of 6.3-6.8. Amino acid analysis revealed that this protein contained high proportions of hydrophobic amino acids (40.4%), and no cysteine could be detected. The N-terminus of the protein was blocked to Edman degradation. Rabbit antiserum raised against the purified 53 kDa protein reacted with the outer envelope of the T. denticola cell surface as confirmed by immunoelectron microscopy. This rabbit antiserum reacted with 4 of the 11 strains of treponemes tested in this study. Sera from 9 to 18 periodontitis patients reacted strongly with this 53 kDa cell envelope protein of T. denticola as determined by immunoblotting analysis.
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1943
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Hasegawa T, Nadai M, Wang L, Takayama Y, Kato K, Nabeshima T, Kato N. Renal excretion of famotidine and role of adenosine in renal failure induced by bacterial lipopolysaccharide in rats. Drug Metab Dispos 1994; 22:8-13. [PMID: 8149895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Our previous studies have reported that bacterial lipopolysaccharide (LPS) dramatically changes the ability of the active tubular anion secretory system in rats. The present study has investigated the effects of LPS on the pharmacokinetics and renal handling of famotidine, an organic cation drug excreted primarily by an active tubular secretion mechanism in rats. The role of adenosine in the LPS-induced renal failure was also investigated using theophylline, an adenosine antagonist. Pretreatment with LPS (250 micrograms/kg) significantly decreased the steady-state volume of distribution, systemic clearance, and renal clearance (CLr) of famotidine, but not nonrenal clearance. No significant differences in total urinary recovery of unchanged famotidine were observed between treatments. Pretreatment with LPS significantly decreased the glomerular filtration rate (GFR), estimated as inulin clearance. LPS increased the clearance ratio of famotidine (CLr/GFR), but not the net tubular secretion, indicating that LPS has little or no effect on the active tubular cation secretory system. Theophylline (10 mg/kg) improved LPS-induced decrease in GFR without causing any changes in the pharmacokinetic parameters of famotidine. These findings provide further evidence that LPS produces different effects on the distribution and the active tubular secretory systems of anion and cation drugs, and that adenosine may play an important role in the induction of renal failure by LPS.
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1944
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el-Farrash MA, Kuroda MJ, Kitazaki T, Masuda T, Kato K, Hatanaka M, Harada S. Generation and characterization of a human immunodeficiency virus type 1 (HIV-1) mutant resistant to an HIV-1 protease inhibitor. J Virol 1994; 68:233-9. [PMID: 8254733 PMCID: PMC236282 DOI: 10.1128/jvi.68.1.233-239.1994] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A synthetic peptide, RPI 312, that specifically inhibits the protease of the human immunodeficiency virus type 1 (HIV-1) showed a potent inhibition on virus production, maturation, and infectivity. Treatment with this agent prevented the cleavage of Gag protein at the site between p17 and p24 in HIV-1 chronically infected MOLT-4 cells as well as in the released virus. Passage of HIV-1 in the presence of gradually increasing concentrations of this protease inhibitor resulted in emergence of a variant that could evade the drug effects. In the resistant variant the maturation of Gag proteins appeared normal, but its infectivity was reduced compared with that of the parent virus. The nucleotides coding the amino acids at and around the cleavage site between Gag proteins p17 and p24 were not changed. One point mutation (A-->G) at site 2082 of the pol gene that resulted in one amino acid change at site 84 of the protease from isoleucine to valine (I-84-->V) could be detected in the resistant variant. An HIV-1 infectious DNA clone with the I-84-->V mutation also showed reduced sensitivity to this protease inhibitor. The findings that the resistant variant had lower infectivity and was still affected by higher doses of the drug support the speculation that resistance to protease inhibitors may not be as problematic as other drug resistance.
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1945
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Miyasato M, Taguchi K, Tsuda S, Kitamura N, Kato K. Eosinophil chemiluminescence response to cytokines and opsonized zymosans in atopic dermatitis. Int Arch Allergy Immunol 1994; 104 Suppl 1:24-6. [PMID: 8155999 DOI: 10.1159/000236742] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Chemiluminescence (CL) responsiveness of eosinophils (Eos) to zymosan particles coated with either IgG, C3 or both and eosinophilopoiesis-modulating cytokines was investigated in patients with atopic dermatitis (AD), and an attempt was made to correlate these CL responses with serum levels of eosinophil cationic protein (ECP) which increased in response to the extent of AD severity, but not blood eosinophil counts. A high degree of positive correlation existed between serum levels of ECP and either IgG containing opsonized zymosan- or interleukin-5 (IL-5)-induced CLs. The CL values induced by these two stimuli appeared to be directly correlated with the intensity of each ligand-linked receptor expression. These results suggested that Fc gamma RII-and/or IL-5R-mediated eosinophil activation at the site of lesional skins might implicate in deterioration of cutaneous inflammation, and consequently cause an elevation of serum levels of ECP in AD.
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1946
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Horie Y, Kato K, Kameoka S, Hamano K. Bu ji (hozai) for treatment of postoperative gastric cancer patients. THE AMERICAN JOURNAL OF CHINESE MEDICINE 1994; 22:309-19. [PMID: 7872243 DOI: 10.1142/s0192415x94000371] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We proposed that postgastrectomy cancer patients with organ deficit were xu zheng, or of deficient constitution, and administered bu ji or supplementary regimen to them. With alleviation of the symptoms, our diagnosis seemed correct from the traditional medicine perspective. Interleukin 2 reactivity, natural killer activity, nutritional index and bone mineral indices also improved. Such results suggest that our diagnosis was also correct according to Western medical theory. In addition, nutrition seemed to have positive relationship with NK activity and bone mineral content. Therefore, administration of bu ji seemed useful to improve the quality of life of postoperative cancer patients.
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1947
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Ono Y, Kato K, Oohira A, Katoh R, Nogami H. Cell function during chondrogenesis and osteogenesis induced by bone morphogenetic protein enclosed in diffusion chamber. Biochemical studies on native products derived from outside differentiating cells. Clin Orthop Relat Res 1994:305-12. [PMID: 8118991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A diffusion chamber containing rabbit bone morphogenetic protein (BMP) was implanted in the abdominal muscle of a Sprague-Dawley rat. Outside of the chamber, cartilage differentiated one to two weeks after implantation, and bone replaced the cartilage three to four weeks after implantation. The interstitial fluid inside the chamber contained only biologic substances produced by cells proliferating and differentiating outside of the chamber. To investigate the cell function during chondrogenesis and osteogenesis, alkaline phosphatase activity and the amounts of S-100 alpha protein, S-100 beta protein, creatine kinase subunits M (CK-M), creatine kinase subunits B (CK-B), hyaluronic acid (HA), and chondroitin sulfate (CS) were measured in the supernatant of interstitial fluid inside the chamber. Alkaline phosphatase activity increased two to four weeks after implantation. The amount of S-100 beta protein acutely increased during the fourth week. The amount of CK-B also increased during the fourth week. The increased levels of HA and CS were also observed after two to four weeks. The examination of such native products may help not only to clarify the mechanisms of cartilage and bone development, but also to develop a sensitive bioassay for BMP.
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1948
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Sado K, Kimura T, Hotta Y, Sakuma H, Hayakawa M, Kato K, Kanai A. Acute retinal necrosis syndrome associated with herpes simplex keratitis. Retina 1994; 14:260-3. [PMID: 7973122 DOI: 10.1097/00006982-199414030-00013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND Although acute retinal necrosis (ARN) syndrome is caused by a herpes group virus, association of herpetic keratitis with ARN syndrome is uncommon. A case of unilateral ARN syndrome with herpes simplex keratitis is discussed. METHODS A 40-year-old man developed unilateral keratitis, necrotic retinitis, retinal vasculitis, vitritis, and iritis consistent with ARN syndrome 1 month after treatment for ipsilateral facial nerve palsy and auricular herpetic vesicles (Tolosa-Hunt syndrome). Impression cytologic examination of the corneal epithelial ulcer that developed concurrent with the intraocular findings and of the aqueous humor (obtained by paracentesis) was performed. RESULTS Cells that reacted with anti-herpes simplex virus type 1 (HSV-1) antibody were detected on impression cytology, and DNA fragments corresponding to the HSV-1 DNA sequence were detected in the aqueous humor. CONCLUSION This case shows that ARN syndrome may, on rare occasions, be associated with herpes keratitis secondary to HSV-1.
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1949
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Onodera K, Kasai S, Kato K, Sawa M, Mito M, Nozawa M. Effects of intrasplenic hepatocyte transplantation in rats congenitally deficient in ascorbic acid biosynthetic enzyme. Cell Transplant 1994; 3 Suppl 1:S31-4. [PMID: 8162304 DOI: 10.1177/096368979400301s13] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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1950
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Yamaguchi H, Lee YJ, Daida H, Yokoi H, Miyano H, Kanoh T, Ishiwata S, Kato K, Nishikawa H, Takatsu F. Effectiveness of LDL-apheresis in preventing restenosis after percutaneous transluminal coronary angioplasty (PTCA): LDL-apheresis angioplasty restenosis trial (L-ART). Chem Phys Lipids 1994; 67-68:399-403. [PMID: 8187240 DOI: 10.1016/0009-3084(94)90162-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To investigate the efficacy of reducing plasma lipoprotein(a) (Lp(a)) as well as low density lipoprotein cholesterol (LDL-C) levels on the prevention of restenosis after PTCA, LDL-apheresis was attempted on a total of 54 patients at six institutions. LDL-apheresis using a dextran sulfate cellulose column has been proven to be an effective method for reducing both plasma Lp(a) and LDL-C levels. As a subgroup (apheresis-drug combined group), 29 of the 54 patients were given Pravastatin (HMG CoA reductase inhibitor) and Niceritrol (Nicotinic Acid) in addition to LDL-apheresis to maintain low plasma levels of both Lp(a) and LDL-C through the follow-up period of 5 months after PTCA. Patients whose plasma Lp(a) levels were reduced by more than 50% showed a lower restenosis rate than those whose plasma Lp(a) levels were reduced by less than 50% (21.2% vs. 52.4%, P = 0.0179), especially in patients with high plasma Lp(a) levels above 30 mg/dl where a much lower restenosis rate (15.0%) was observed. Furthermore, in the apheresis-drug combined group, the restenosis rate was 11.8% regardless of baseline plasma Lp(a) levels, including even those below 30 mg/dl. In conclusion, in patients with high plasma Lp(a) levels, a greater than 50% reduction in Lp(a) levels by LDL-apheresis is effective in preventing restenosis after PTCA. If the plasma Lp(a) reduction rate is greater than 50%, LDL-apheresis combined with lipid-lowering drugs such as niceritrol and pravastatin seems to be more effective, even in patients with low plasma Lp(a) levels.
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