476
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Kato A, Takahashi H, Takahashi Y, Matsushime H. Inactivation of the cyclin D-dependent kinase in the rat fibroblast cell line, 3Y1, induced by contact inhibition. J Biol Chem 1997; 272:8065-70. [PMID: 9065480 DOI: 10.1074/jbc.272.12.8065] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Cyclin-dependent kinase (Cdk) inhibitory proteins are involved in cell cycle arrest induced by antiproliferating factors or chemicals. High cell density also induces cell cycle arrest in which the genomic DNA is unreplicated, even in the presence of a mitotic dose of growth factors; this is termed contact inhibition. Although the cell cycle of the rat fibroblast cell line, 3Y1, was arrested in quiescence by contact inhibition, the Cdk4 bound to its regulatory subunit, cyclin D1 or D3. However, these complexes were enzymatically inactive. Phosphorylation of the cyclin D1-bound Cdk4 by the Cdk-activating kinase could convert the inactive cyclin D1-Cdk4 complex into its active form in vitro, suggesting that threonine 172 of the Cdk4, of which phosphorylation is required for its activation, was in part unphosphorylated in contact-inhibited 3Y1 cells. Although MO15 was active in cell extracts prepared from the arrested 3Y1 cells, activation of bacterially produced Cdk4 in the cell extracts was inhibited. Removal of p27(kip1) from the cell extracts allowed the MO15 holoenzyme to phosphorylate the Cdk4 and in turn activate it, indicating that p27(kip1) plays a role in inhibiting the phosphorylation of Cdk4 by MO15 in the contact-inhibited 3Y1 cells.
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477
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Kato A. [Effect of erythromycin and clarithromycin on ion transport across dissected canine tracheal epithelium]. NIHON JIBIINKOKA GAKKAI KAIHO 1997; 100:351-6. [PMID: 9103848 DOI: 10.3950/jibiinkoka.100.351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Since erythromycin was shown to be effective in the treatment of patients with diffuse panbronchiolitits, newly discovered effects of macrolide antibiotics have attracted much attention. It was reported that erythromycin inhibits Cl secretion across cultured canine tracheal epithelial cells. Erythromycin may decrease the movement of water toward the lumen, thus reducing sputum volume. We tested the hypothesis that erythromycin and clarithromycin have a similar effect on the dissected canine tracheal epithelium, by measuring the short circuit current using Ussing chambers. Addition of erythromycin or clarithromycin did not change the short circuit current within 20 minutes when applied on either the mucosal side or the submucosal side. No changes in the short circuit current were observed after pretreatment of the epithelium with amiloride, an Na channel blocker, or bumetanide, a Cl transport inhibitor, and subsequent addition of the macrolide antibiotics. These data indicate that neither erythromycin nor clarithromycin has any short term effect on ion transport in the dissected canine tracheal epithelium.
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478
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Abstract
We describe the CT findings of intraorbital wooden and bamboo foreign bodies in the acute, subacute, and chronic stages. We examined four patients using CT a total of seven times. The CT findings were reviewed. There were three dry wooden foreign bodies. CT within a day of the accident demonstrated wooden foreign bodies as low density relative to surrounding orbital fat, while CT 8-29 days after the accident showed them as denser than the extraocular muscles. In the acute stage, dry wooden foreign bodies mimic air bubbles. Wooden foreign bodies in the subacute and chronic stages should be included in the differential diagnosis of intraorbital lesions of soft tissue density or above on CT of traumatised orbits. There was one dry bamboo foreign body. Within a day of the accident it was recognised as linear lesion isodense with fat. Therefore, such foreign bodies may be missed on CT when located in the orbital fat.
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479
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Ohashi Y, Tanaka A, Kakinoki Y, Ohno Y, Sakamoto H, Kato A, Masamoto T, Wahio Y, Nakai Y. Serum level of soluble interleukin-2 receptor in patients with seasonal allergic rhinitis. Scand J Immunol 1997; 45:315-21. [PMID: 9122623 DOI: 10.1046/j.1365-3083.1997.d01-392.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The rate of release of the soluble form of interleukin-2 receptor (soluble IL-2R) reflects T cell activation in vivo. Since T lymphocytes play a central role in respiratory allergic disorders, the measurement of serum levels of soluble IL-2R may be useful in analysing the disease state of allergic disorders. The study has aimed at investigating the seasonal changes in serum soluble IL-2R in 81 patients with seasonal allergic rhinitis due to Japanese cedar pollens, with special reference to the effect of anti-allergic pharmacotherapy and immunotherapy. Serum samples were obtained twice from each patient, before and during the pollen season, and all the serum samples were simultaneously used for determination of soluble IL-2R and cedar pollen-specific immunoglobin E (IgE). Seasonal elevation in soluble IL-2R was not associated with the good clinical outcome but was associated with the poor clinical outcome, irrespective of pharmacotherapy or immunotherapy. Additionally, successful immunotherapy suppressed seasonal elevation of serum soluble IL-2R more strongly than successful pharmacotherapy, and seasonal increase rates in soluble IL-2R were inversely correlated with the duration of immunotherapy. Seasonal increase rates in soluble IL-2R were significantly correlated with seasonal increase rates in specific IgE in both the medication group and the immunotherapy patients. These results may suggest that seasonal changes in serum soluble IL-2R may serve as an indicator for clinical outcome of seasonal allergic rhinitis, that the magnitude of T cell activation could affect specific IgE production, and that T cell activation could be gradually modulated as immunotherapy proceeds. In conclusion, seasonal changes in serum soluble IL-2R may serve as an objective indicator for clinical outcome of seasonal allergic rhinitis.
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MESH Headings
- Adolescent
- Adult
- Antibody Specificity
- Desensitization, Immunologic
- Female
- Humans
- Immunoglobulin E/blood
- Male
- Middle Aged
- Receptors, Interleukin-2/blood
- Rhinitis, Allergic, Seasonal/blood
- Rhinitis, Allergic, Seasonal/drug therapy
- Rhinitis, Allergic, Seasonal/immunology
- Rhinitis, Allergic, Seasonal/therapy
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480
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Suzuki F, Kobayashi M, Komatsu Y, Kato A, Pollard RB. Keishi-ka-kei-to, a traditional Chinese herbal medicine, inhibits pulmonary metastasis of B16 melanoma. Anticancer Res 1997; 17:873-8. [PMID: 9137420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Keishi-ka-kei-to, a traditional Chinese herbal medicine composed of a mixture of crude extracts from five medicinal plants (Cinnamomi cortex, Paeoniae radix, Zizyphi fructus, Zingiberis rhizoma and Glycyrrhizae radix), inhibited experimental pulmonary metastasis in mice implanted with B16F10 melanoma cells. When 136 to 145 metastatic colonies were produced in lungs of mice inoculated with 1 x 10(5) cells/mouse of melanoma cells, less than 15 metastatic colonies were demonstrated when these tumor-inoculated mice were treated orally with 80 to 320 mg/kg doses of Keishi-ka-kei-to. The most active component in the mixture was shown to be 6-gingerol, derived from the Zingiberis rhizoma extract. The antimetastatic activity of 6-gingerol was expressed through the host's antitumor immune functions, as the growth of B16F10 melanoma cells was not affected by this substance in vitro. The splenic CD8+ T cells from mice treated with the compound showed inhibitory activities on pulmonary metastasis when these T cells were adoptively transferred to mice bearing B16F10 melanoma cells. These results may suggest that Keishi-ka-kei-to inhibits pulmonary metastasis in mice bearing B16F10 melanoma cells through the stimulation of CD8+ T cells.
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481
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Kato A, Asano N, Kizu H, Matsui K. Fagomine isomers and glycosides from Xanthocercis zambesiaca. JOURNAL OF NATURAL PRODUCTS 1997; 60:312-314. [PMID: 9157194 DOI: 10.1021/np960646y] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
50% aqueous MeOH extracts from the leaves and roots of Xanthocercis zambesiaca (Leguminosae) were subjected to various ion-exchange column chromatographic steps to give fagomine (1), 3-epi-fagomine (2), 3,4-di-epi-fagomine (3), 3-O-beta-D-glucopyranosylfagomine (4), and 4-O-beta-D-glucopyranosylfagomine (5). Their structures were determined by spectroscopic analyses, particularly by extensive 1D and 2D NMR studies. Compounds 3 and 4 are new natural products. Compound 1 is a good inhibitor of isomaltase and certain alpha- and beta-galactosidases. Whereas 2 is a more potent inhibitor of isomaltase and beta-galactosidases than 1, it does not inhibit alpha-galactosidase. Compounds 3-5 exhibited no significant inhibition against the glycosidases used.
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482
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Kato A, Kiyotani K, Sakai Y, Yoshida T, Nagai Y. The paramyxovirus, Sendai virus, V protein encodes a luxury function required for viral pathogenesis. EMBO J 1997; 16:578-87. [PMID: 9034340 PMCID: PMC1169661 DOI: 10.1093/emboj/16.3.578] [Citation(s) in RCA: 178] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The Sendai virus (SeV) V protein is characterized by the unique cysteine-rich domain in its carboxy-terminal half which is fused to the amino-terminal half of the P protein, but its function has remained enigmatic. The V protein-directing mRNA is generated by a remarkable process known as mRNA editing involving the pseudotemplated addition of a single G residue at a specific septinucleotide locus in the P gene, whereas the unedited exact copy encodes the P protein. Here, we introduced two nucleotide changes in the septinucleotide motif (UUUUCCC to UUCUUCC) in a full-length SeV cDNA and were able to recover a virus from the cDNA, which was devoid of mRNA editing and hence unable to synthesize the V protein. Compared with the parental wild-type virus with regard to gene expression, replication and cytopathogenicity in various cell lines in vitro, the V(-) virus was found to be either potentiated or comparable but never attenuated. The V(-) virus, however, showed markedly attenuated in vivo replication capacity in and pathogenicity for mice. Thus, though categorized as a nonessential gene product, SeV V protein encodes a luxury function required for in vivo pathogenicity.
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483
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Yamamoto T, Wakisaka N, Sato F, Kato A. Comparison of the nucleotide sequence of enteroaggregative Escherichia coli heat-stable enterotoxin 1 genes among diarrhea-associated Escherichia coli. FEMS Microbiol Lett 1997; 147:89-95. [PMID: 9037769 DOI: 10.1111/j.1574-6968.1997.tb10225.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The presence of the enteroaggregative Escherichia coli (EAggEC) heat-stable enterotoxin 1 (EAST1) gene was investigated in 15 strains each of EAggEC, enteropathogenic E. coli (EPEC), EPEC-related strains of non-EPEC serotypes, diffusely adhering E. coli (type 1 DAEC) that carries F1845 adhesive pili (or a related adhesin), and enteroinvasive E. coli (EIEC) by PCR and colony hybridization. The EAST1 gene or its homologue was present in 53.3% of EAggEC, 20% of EPEC, 13.3% of the EPEC-related strains, and 6.7% of type 1 DAEC, EIEC and E. coli unrelated with diarrhea had no gene with sequence similarity to the EAST1 gene. Comparison of the EAST1 gene sequences analyzed in this study as well as those reported previously showed that EAggEC (including strain O42, which was shown to be pathogenic in volunteer experiments), EPEC, type 1 DAEC, type 2 DAEC (which carries the 57-kDa outer membrane protein as an adhesin), and enterotoxigenic E. coli shared a common sequence. A variant type of the EAST1 gene sequence was present in the EAggEC strain 17-2 (initially characterized for the EAST1 gene) and in an EPEC-related strain of a non-EPEC serotype. These data suggest that the EAST1 gene or its variant is a virulence gene widely distributed among diarrhea-associated E. coli.
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484
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Nakajima S, Kato A, Yoshimine T, Sakurai K, Harada K, Hayakawa T. A reconstruction method of cerebral surface anatomical images for image guided localization. J Clin Neurosci 1997; 4:80-4. [PMID: 18638933 DOI: 10.1016/s0967-5868(97)90020-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/1994] [Accepted: 08/26/1994] [Indexed: 11/18/2022]
Abstract
We have developed a simple and practical method to reconstruct cerebral surface anatomical images for better presurgical planning and surgical orientation with the aid of a personal computer. The area representing the cortical surface was selected from the most superficial slice of the T1-weighted magnetic resonance (MR) images. The selected area was then overlaid upon the next superficial slice and the alignment adjusted. By repeating this procedure four to seven times we obtained a brain surface image which clearly displayed gyri and sulci. With the same method images of the vascular components of the cerebral surface were obtained from the T2-weighted images or MR angiograms. The brain surface and the vascular images were then combined to reconstruct a surface anatomical image (SAI). In addition, the outline of the lesion and natural landmarks, such as ventricles, were added if necessary. Compared to conventional surface anatomy scanning (SAS) or three-dimensional image reconstruction procedures, our method has the advantage of displaying, within a reasonable time, the manifest cortical surface from the direction of the planned surgical approach. The SAIs obtained for individual patients have proven to be useful for presurgical planning and minimizing surgical damage to the eloquent cortex in approaching both surface and subcortical lesions.
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485
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Kato A, Kitamura T, Sugimoto C, Ogawa Y, Nakazato K, Nagashima K, Hall WW, Kawabe K, Yogo Y. Lack of evidence for the transmission of JC polyomavirus between human populations. Arch Virol 1997; 142:875-82. [PMID: 9191854 DOI: 10.1007/s007050050125] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Human polyomavirus JC virus (JCV), the causative agent of progressive multifocal leukoencephalopathy, is ubiquitous in humans, infecting children asymptomatically then persisting in renal tissue. Since JCV DNA can readily be detected from urine, it should be a useful tool with which to study the mode of virus transmission in humans. Based on this notion, we examined the extent to which JCV was transmitted from the American to Japanese populations in Okinawa Island, Japan. (A population of about 50 000 American soldiers and families have been stationed in Okinawa since 1945.) Four JCV types (A to D) were identified in American populations in U.S.A., whereas only type B was prevalent in elder Japanese in Okinawa who had reached adulthood by 1945. Thus, types A, C, and D served as indicators of the transmission of JCV from American to Japanese populations. We then examined whether types A, C, and D were detectable in Japanese in Okinawa aged 30-50 years who may have been in contact with Americans during childhood. However, all the 125 isolates from the younger Japanese population were type B without exception. From this finding, we concluded that JCV is rarely transmitted between human populations.
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486
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Uchino A, Kato A, Momozaki N, Yukitake M, Kudo S. Spinal cord herniation: report of two cases and review of the literature. Eur Radiol 1997; 7:289-92. [PMID: 9038133 DOI: 10.1007/s003300050153] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Idiopathic herniation of the spinal cord is an extremely rare disorder which may cause progressive myelopathy. Two cases of this entity reported herein were both examined using MRI and CT myelography. The typical appearance of this disease with or without a dorsal intradural arachnoid cyst is focal ventral displacement of the mid-thoracic spinal cord, mimicking an isolated intradural spinal arachnoid cyst on MRI. CT myelography using thin slice sections is useful in the diagnosis of this disease.
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487
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Nakai Y, Sakashita T, Kubo T, Yamane H, Masutani H, Kato A, Iguchi H, Takayama M, Ito J. Temporal bone pathology of a patient with cochlear implant. Adv Otorhinolaryngol 1997; 52:60-1. [PMID: 9042451 DOI: 10.1159/000059008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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488
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Matsumoto-Mizuno Y, Okazaki K, Kato A, Yoshimine T, Sato Y, Tamura S, Yamashita K. [Localization of epileptogenic foci and visualization of propagating process in the seizure discharges using crosscorrelation analysis]. NO TO SHINKEI = BRAIN AND NERVE 1997; 49:59-64. [PMID: 9027903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Electrocorticogram (ECoG) of intractable focal epilepsy was analyzed using AR model, wavelet analysis and crosscorrelation analysis. The sequential 3-dimensional visualization technique of phase shift maps was developed to localize the epileptic foci and to study their propagation process. The crosscorrelation of the epileptic discharges was calculated between the electrodes in every unit of time, to get the phase shift. More than two epileptogenic foci were localized and two kinds of propagating process were shown. These findings suggest that two kinds of mechanism might work in development of epileptic discharges, and our newly developed visualization technique is useful to investigate the epileptogenesis etiology.
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489
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Miura T, Kato A. Hypoglycemic action of embelia madagascariensis in normal and diabetic mice. THE AMERICAN JOURNAL OF CHINESE MEDICINE 1997; 25:169-73. [PMID: 9288363 DOI: 10.1142/s0192415x97000196] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The hypoglycemic effect of Embelia madagascariensis (Myrsinaceae) was investigated in both normal and streptozotocin-induced diabetic mice. The methanol extract of leaves of Embelia madagascariensis (EL)(500 mg/kg) reduced the blood glucose of normal mice from 206 +/- 9 to 137 +/- 10 mg/100 ml 4 hours after intraperitoneal administration (P < 0.001), and also significantly lowered the blood glucose of streptozotocin-induced diabetic mice from 570 +/- 29 to 401 +/- 59 mg/100 ml under similar conditions (P < 0.05). EL also suppressed epinephrine-induced hyperglycemia in mice (control vs EL, P < 0.01).
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490
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Kato A, Hishida A, Tanaka I, Komatsu K. Uninephrectomy prevents the ischemia-induced increase in renin activity. Nephron Clin Pract 1997; 75:72-6. [PMID: 9031273 DOI: 10.1159/000189502] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Contralateral uninephrectomy attenuates unilateral ischemic injury. The present work was performed to elucidate whether the beneficial effect of uninephrectomy was associated with the modification of ischemia-induced changes in plasma or renal renin activity. A 60-min left renal artery occlusion was conducted in right nephrectomized (Nx) and sham-nephrectomized (Sham-Nx) rats. The decline in inulin clearance 48 h after ischemia was significantly less in Nx rats than in Sham-Nx animals (0.50 +/- 0.10 vs. 0.052 +/- 0.029 ml/min/kidney, p < 0.05). Following ischemia, plasma renin activity (PRA) significantly increased in Sham-Nx (from 5.4 +/- 0.9 to 15.5 +/- 1.4 ng AI/ml/min, p < 0.01) but not in Nx (from 3.5 +/- 0.5 to 5.0 +/- 1.0 ng AI/ml/ min) animals. PRA and renal cortical renin content (2,200 +/- 225 vs. 1,257 +/- 187 ng AI/h/mg protein, p < 0.05) were significantly less in Nx rats than in Sham-Nx animals 48 h after renal ischemia. The decrease in body weight was greater in Nx rats than in Sham-Nx animals. Plasma atrial natriuretic peptide (ANP) (195 +/- 30 vs. 302 +/- 40 pg/ml, p < 0.05) and renal dopamine (DA) content (3.2 +/- 0.5 vs. 13.7 +/- 1.3 ng/g tissue, p < 0.01) were rather lower in the Nx group when compared with the Sham-Nx group. No significant difference was found in the intrarenal content of norepinephrine (NE) between two ischemic groups. These findings suggested that uninephrectomy prevents the ischemia-induced increase in renin activity. The prevention of the increase in renin activity in Nx rats is not be mediated through the modulation of ischemia-induced changes in sodium balance, plasma ANP level and/or intrarenal contents of NE and DA.
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491
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492
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Kato A, Yamada H, Yamada T, Ishinaga H. [Fine needle aspiration cytology under ultrasonographic imaging for diagnosis of thyroid tumor]. NIHON JIBIINKOKA GAKKAI KAIHO 1997; 100:45-50. [PMID: 9038075 DOI: 10.3950/jibiinkoka.100.45] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
During a 66-month period, 2849 patients with thyroid gland tumor were examined by fine needle aspiration cytology (FNA) under ultrasonographic imaging at Yamada Red Cross Hospital. Of these patients, 333 received surgical therapy and histological examinations were performed. FNA yielded an accuracy of 92.4%, a specificity of 100% and a sensitivity of 88.3%. There were 16 false-negative reports which were mainly considered to be due to calcified lesions, cystic lesion, or follicular carcinoma. Among the 188 negative cases, 24 cases (12.8%) proved to be positive by repeated FNA-Preoperative FNA provides cytological information and may assist in the determination of the operative indication. This approach resulted in an increased rate of surgery of thyroid malignancies among all thyroid gland surgeries. This method need to be improved to reduce false-negative results and the combination of FNA diagnosis and other examination is necessary.
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493
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Uchino A, Kato A, Kuroda Y, Shimokawa S, Kudo S. Pontine venous congestion caused by dural carotid-cavernous fistula: report of two cases. Eur Radiol 1997; 7:405-8. [PMID: 9087366 DOI: 10.1007/s003300050175] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
This is a report of two patients in whom a pontine venous congestion occurred with a dural carotid-cavernous fistula (CCF), an extremely rare complication. This is the first such report. We underscore the importance of early diagnosis and treatment of dural CCFs.
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494
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Matsumoto K, Uchino A, Kato A, Kudo S, Kuno T. CT and MRI of sellar spine with upward extension of the pituitary gland: case report. Eur Radiol 1997; 7:287-8. [PMID: 9038132 DOI: 10.1007/s003300050152] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This is a report of CT and MRI findings in a patient with a sellar spine which caused deformity of the pituitary gland. The sellar spine is an infrequent anatomical variant characterized by an osseous spine which arises in the midline from the anterior aspect of the dorsum sellae and extends into the pituitary fossa. The CT and MRI findings of sellar spine have been described in previous reports; however, only one investigator reported deformity of the pituitary gland as revealed by CT. This is the first report of the MRI finding of the sellar spine associated with a deformity and superior extension of the pituitary gland, mimicking pituitary hypertrophy.
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495
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Fukunaga T, Miura T, Furuta K, Kato A. Hypoglycemic effect of the rhizomes of Smilax glabra in normal and diabetic mice. Biol Pharm Bull 1997; 20:44-6. [PMID: 9013805 DOI: 10.1248/bpb.20.44] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The hypoglycemic effect of the rhizomes of Smilax glabra ROXBURGH (Liliaceae) was investigated in normal and KK-Ay mice, one of the animal models of non-insulin dependent diabetes mellitus (NIDDM) with hyperinsulinemia. The methanol extract of rhizomes of Smilax glabra ROXBURGH (SM, 100 mg/kg body weight) reduced the blood glucose of normal mice 4 h after intraperitoneal administration (p<0.05), and also significantly lowered the blood glucose of KK-Ay mice under similar conditions (p<0.001). However, SM did not affect the blood glucose in streptozotocin-induced diabetic mice, one of the animal models of insulin-dependent diabetes mellitus (IDDM) with hypoinsulinemia. SM also suppressed epinephrine-induced hyperglycemia in mice. SM-treated KK-Ay mice significantly decreased the blood glucose in an insulin tolerance test. We concluded that the hypoglycemic effect of SM raised insulin sensitivity.
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496
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Rahman F, Kato A, Kawahara K, Nakajima T. Y-26763 protects the working rat myocardium from ischemia/reperfusion injury through opening of KATP channels. Eur J Pharmacol 1996; 317:293-9. [PMID: 8997613 DOI: 10.1016/s0014-2999(96)00741-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This investigation was undertaken to determine the possible protection against ischemia afforded by Y-26763, [(-)-(3S,4R)-4-(N- acetyl-N-hydroxyamino)-6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran- 3- ol], which has K+ channel-opening properties, in isolated rat hearts under working conditions. This preparation was subjected to 28 min of global ischemia followed by 30 min of reperfusion. Drugs were injected into the aortic cannula prior to ischemia. Compared to control, Y-26763 (1 microM) resulted in a significant recovery of post-ischemic cardiac functions, significant reduction of cellular enzyme loss, and preserved significantly the stocks of cellular high-energy phosphates and the myocyte ultrastructure. These effects of Y-26763 were completely prevented by glibenclamide (10 microM), a specific K+ channel blocker of KATP channels. In non-ischemic conditions, Y-26763 significantly increased coronary flow without affecting cardiac output and heart rate. The data were analyzed statistically by analysis of variance. The results clearly demonstrate that Y-26763 protects the myocardium from ischemic injury by opening KATP channels.
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497
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Iwaki D, Kawabata S, Miura Y, Kato A, Armstrong PB, Quigley JP, Nielsen KL, Dolmer K, Sottrup-Jensen L, Iwanaga S. Molecular cloning of Limulus alpha 2-macroglobulin. EUROPEAN JOURNAL OF BIOCHEMISTRY 1996; 242:822-31. [PMID: 9022715 DOI: 10.1111/j.1432-1033.1996.0822r.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The American horseshoe crab Limulus polyphemus contains alpha 2-macroglobulin (alpha 2M) in the hemolymph plasma and hemocytes. alpha 2M from Limulus shows many of the typical characteristics of mammalian alpha 2M, including the presence of an internal thiol-ester, reactivity with a diversity of endopeptidases, a unique proteinase-trapping mechanism, and reactivity with the mammalian alpha 2M receptor. Additionally, Limulus alpha 2M has the unique property that it regulates the limulin-based hemolytic system of the plasma. A cDNA encoding Limulus alpha 2M has been obtained from a hemocyte cDNA library. The open reading frame encodes an N-terminal signal sequence of 25 amino acid residues and a mature protein of 1482 residues. The entire amino acid sequence is similar to those of the mammalian alpha 2Ms (28-29% identity) and contains common features found in mammalian alpha 2Ms. a bait region, an internal thiol-ester site, and a receptor-binding domain. However, the N-terminal portion (positions 24-105) has no sequence similarity with those of mammalian alpha 2Ms, and it is structurally related to that of the human complement factor C8 chain, consistent with a role for Limulus alpha 2M in host defense. The component sugar analysis of Limulus alpha 2M showed the existence of a complex type of oligosaccharide chain similar to those of mammalian alpha 2M. However, unlike mammalian alpha 2M, no sialic acid was detected in Limulus alpha 2M and it contained approximately 3 mol/mol N-acetylgalactosamine, suggesting the presence of O-linked sugar chains, which have not been found in mammalian alpha 2M. Expression of alpha 2M was detected in hemocytes, but not in hepatopancreas, heart, stomach, intestine, coxal gland, brain and skeletal muscle. Furthermore, immunoblotting of large and small granules of the hemocytes with antiserum against alpha 2M indicated the presence of the alpha 2M in large granules. Trypsin-treated Limulus alpha 2M, but not the native alpha 2M, displaced methylamine-treated human 125I-alpha 2M from the human alpha 2M receptor with a Kd of 30 nM, suggesting conservation of the proteinase-clearance mechanisms between mammalian and arthropod evolutionary lineages.
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498
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Kitamura K, Miyagawa K, Urabe A, Sato H, Obayashi Y, Aoki I, Takaku F, Togawa A, Shindou E, Wakabayashi Y, Ohshima T, Horikoshi A, Nomura T, Ohki I, Suzuki K, Kamakura M, Oguchi A, Toyama K, Yaguchi M, Aoki N, Kato A, Mizoguchi H, Masuda M, Irie S, Fujioka S. [Clinical study on a concomitant therapy with fluconazole and human recombinant granulocyte colony stimulating factor in the treatment of systemic fungal infections with hematological disorders]. THE JAPANESE JOURNAL OF ANTIBIOTICS 1996; 49:1062-72. [PMID: 9032593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The clinical efficacy and the safety of concomitant therapy with fluconazole and recombinant human granulocyte colony stimulating factor (rhG-CSF) was compared with fluconazole monotherapy in neutropenic patients with hematological disorders. The clinical efficacy rate was 73.5% (25/34) in the combination therapy and 48.1% (37/77) in monotherapy. The difference between the two is statistically significant. Side effects were not observed in the combination group, but laboratory abnormalities were found in 6 patients with an incident rate of 11%. The combination therapy with fluconazole and rhG-CSF may be selected as empiric therapy for systemic fungal infection associated with hematological disorders, since this combination therapy showed high efficacy and low incident of side effects. Some patients, however, did not show increased neutrophil counts in spite of rhG-CSF administration.
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499
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Nakatani K, Kawanabe Y, Kato A, Tanaka T. Interaction of propranolol with S100 proteins of the cardiac muscle. Eur J Pharmacol 1996; 315:335-8. [PMID: 8982673 DOI: 10.1016/s0014-2999(96)00611-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The cardioprotective activity of propranolol is believed to be independent of its beta-adrenoceptor antagonistic effect. Propranolol exerts this effect through a direct effect on the cardiac muscle, but the precise mechanism remains unclear. In this work, we demonstrated that propranolol binds to S100ao and S100L proteins with ED50 of approximately 1.0 microM without cation dependency and that this binding changes the conformation of these S100 proteins. Propranolol, however, was found to bind to and to change the conformation of S100C protein in the presence of Mg2+ or Zn2+ with ED50 of approximately 1.0 microM. No change was observed in the presence of Ca2+. Moreover, in the presence of Mg2+, the ED50 of L- and D- propranolol were approximately 0.8 and 2.0 microM, respectively. This study demonstrated for the first time, that the S100 proteins of the cardiac muscle are intracellular targets of propranolol, and that Mg2+ is a modulator of the cardioprotective activity of S100C protein.
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500
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Asano N, Kato A, Kizu H, Matsui K, Watson AA, Nash RJ. Calystegine B4, a novel trehalase inhibitor from Scopolia japonica. Carbohydr Res 1996; 293:195-204. [PMID: 8938376 DOI: 10.1016/0008-6215(96)00204-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
GLC-MS analysis has been developed for screening plants of the family Solanaceae for new calystegines. GLC-MS analyses of the extract of Scopolia japonica showed the presence of a new tetrahydroxy-nor-tropane alkaloid in addition to the known calystegines A3, A5, B1, B2, B3, and C1. We gave this new alkaloid the trivial name calystegine B4. The structure of calystegine B4 was determined as 1 alpha, 2 beta, 3 alpha, 4 alpha-tetrahydroxy-nor-tropane from a variety of NMR spectral data. Calystegines B1, B2, and C1 are potent competitive inhibitors with Ki values ranging from 10(-6) to 10(-7) M for almond beta-glucosidase, while calystegine B4 inhibited this enzyme in a competitive manner, with a Ki value of 7.3 microM. Calystegine B2 is also a potent inhibitor of green coffee bean alpha-galactosidase, whereas calystegine B4 exhibited no significant activity for this enzyme. Among rat intestinal glycosidases, only trehalase was potently inhibited by calystegine B4, with an IC50 value of 9.8 microM. Furthermore, calystegine B4 potently inhibited pig kidney trehalase in a competitive manner, with a Ki value of 1.2 microM, but it was almost inactive against yeast and fungal trehalases.
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