1501
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Shibagaki Y, Gotoh H, Kato M, Mizumoto K. Localization and in vitro mutagenesis of the active site in the Saccharomyces cerevisiae mRNA capping enzyme. J Biochem 1995; 118:1303-9. [PMID: 8720151 DOI: 10.1093/oxfordjournals.jbchem.a125023] [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: 02/01/2023] Open
Abstract
The yeast mRNA capping enzyme is composed of 52 (alpha) and 80 kDa (beta) polypeptides, which are responsible for its mRNA guanylyltransferase and RNA 5'-triphosphatase activities, respectively. We isolated the gene encoding the alpha subunit (CEG1) and showed that CEG1 is essential for yeast cell growth [Shibagaki et al., (1992) J. Biol. Chem. 267, 9521-9528]. In this study, CEG1 was expressed in Escherichia coli and the alpha subunit protein was purified to near homogeneity. A [32P]GMP-bound tryptic peptide derived from the recombinant enzyme-[32P]GMP covalent reaction intermediate was converted to a [32P]phosphoryl-peptide through periodate oxidation followed by beta-elimination. Hydrolysis of the [32P]phosphoryl-peptide with alkali resulted in [32P]N epsilon-phospholysine as the only phosphoamino acid, indicating that GMP in the enzyme-GMP complex is bound to a lysine residue via a phosphoamide linkage. Microsequencing of the [32P]GMP-peptide showed that the GMP binding site was located in the region between amino acids 60 and 75, which contained an internal trypsin-resistant lysine at position 70. CEG1 was subjected to site-directed mutagenesis and the mutant proteins were expressed in E. coli. Substitution of His or Ile for Lys70 entirely abolished the enzyme-GMP formation activity, and this mutation was lethal to yeast in vivo, supporting the notion that the active site in the alpha subunit is located at Lys70. Replacement of Lys70 with Arg reduced the ability to form the enzyme-GMP complex; however, yeast cells bearing this allele were not viable. A series of mutations, including 8 amino acid replacements and 3 insertions, near the active site (Lys70-Thr-Asp-Gly motif) were also introduced and the mutant polypeptides were examined for catalytic activity in vitro as well as yeast cell viability in vivo. There was a good correlation between the in vitro and in vivo functions of the mutant proteins, except when Asp72 was replaced with Glu, which allowed formation of the enzyme-GMP complex but failed to support cell growth. The results with Lys70 to Arg and Asp72 to Glu substitutions indicated that guanylyltransfer to RNA and/or additional roles besides cap formation per se are impaired in these mutant proteins.
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1502
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Tobimatsu S, Tomoda H, Kato M. Parvocellular and magnocellular contributions to visual evoked potentials in humans: stimulation with chromatic and achromatic gratings and apparent motion. J Neurol Sci 1995; 134:73-82. [PMID: 8747847 DOI: 10.1016/0022-510x(95)00222-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Psychophysical evidence suggests that two major parallel pathways, the parvocellular (P) and the magnocellular (M) pathways, exist in humans. We herein report that responses specific to the P and M systems can be recorded in human visual evoked potentials (VEPs) by using the appropriate stimuli. The onset of isoluminant chromatic (red-green) and high contrast achromatic sinusoidal gratings were used for stimulating the P-system. A chromatic stimulation evoked a characteristic negative wave (N1) with peak latencies around 120 msec. The amplitude showed an inverse U-shaped function as a function of spatial frequency with a peak at 2 c/deg. In contrast, VEPs to achromatic (black-white) gratings showed different spatial frequency characteristics with a peak at 5.3 c/deg. By varying the luminous intensity ratio between the red and green gratings, N1 was found to reach a maximum during isoluminant stimulation. An apparent motion display was used for stimulating the M-system. The speed of alternation (i.e., the interstimulus interval (ISI)) was varied to record both the transient and steady-state VEPs. Transient VEPs showed triphasic waves with the major positive peak (P1) at around 120 ms. Steady-state VEPs were quasi-sinusoidal waveforms, depending on the ISI, and were quite stable across all subjects. There was a also high correlation between the motion threshold and the VEP amplitude. The above observations indicate that characteristic potentials may distinguish between these two parallel visual systems in humans. Thus, the combined use of isoluminant color and high contrast achromatic gratings and an apparent motion display is considered to be useful for evaluating both systems electrophysiologically.
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1503
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Kato M, Yamashina S, Takeda N, Mochizuki S, Morishita T, Nagano M. Molecular biological and quantitative abnormalities of ADP/ATP carrier protein in cardiomyopathic hamsters. Eur Heart J 1995; 16 Suppl O:78-80. [PMID: 8682109 DOI: 10.1093/eurheartj/16.suppl_o.78] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The adenine nucleotide translocator or ADP/ATP carrier protein (AAC) is an integral protein present in the inner mitochondrial membrane, which performs the exchange of cytoplasmic and intramitochondrial ADP and ATP. The myocardial AAC content was studied in J-2-N cardiomyopathic hamsters. The AAC content was found to be significantly decreased in J-2-N hamsters. For molecular biological analysis, hamster AAC (T1 isoenzyme) cDNA was cloned by the plaque hybridization method. This AAC cDNA hybridized specifically with AAC mRNA, so RNA dot-blot hybridization was performed. The highest AAC mRNA level was observed in control hamsters followed by J-2-N hamsters with mild myocardial damage, J-2-N hamsters with severe myocardial damage and Bio 14-6 cardiomyopathic hamsters. These results suggest that a decreased AAC content may contribute to the pathogenesis of cardiomyopathy and that a decrease of AAC mRNA levels may explain the abnormalities of AAC in J-2-N cardiomyopathic hamsters.
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1504
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Nakamura S, Sasajima Y, Koshikawa T, Kitoh K, Kato M, Ueda R, Mori S, Suchi T. Ki-1 (CD30) positive anaplastic large cell lymphoma of T-cell phenotype developing in association with long-standing tuberculous pyothorax: report of a case with detection of Epstein-Barr virus genome in the tumor cells. Hum Pathol 1995; 26:1382-5. [PMID: 8522314 DOI: 10.1016/0046-8177(95)90306-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We report a case of CD30 positive anaplastic large cell lymphoma of T-cell phenotype developing in association with long-standing tuberculous pyothorax. Phenotypic analysis showed CD1a-, CD2+, CD3+, CD4+, CD5-, CD8-, CD10-, CD19-, CD20 +/-, CD21-, CD25-, CD56-, T-cell receptor (TCR) alpha/beta antigens-, and HLA-DR+ phenotype. Neither rearrangement of TCR beta and gamma chain genes or of immunoglobulin heavy chain gene was detected in DNA extract from fresh material. The lymphoma cells were also shown to express the latent membrane protein-1 and the Epstein-Barr virus (EBV)-encoded nuclear antigen-2 by immunohistochemistry and EBV-encoded small RNAs by in situ hybridization.
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MESH Headings
- Aged
- Empyema, Tuberculous/complications
- Empyema, Tuberculous/pathology
- Empyema, Tuberculous/virology
- Herpesvirus 4, Human/genetics
- Herpesvirus 4, Human/isolation & purification
- Humans
- Immunophenotyping
- In Situ Hybridization
- Lymphoma, Large-Cell, Anaplastic/complications
- Lymphoma, Large-Cell, Anaplastic/pathology
- Lymphoma, Large-Cell, Anaplastic/virology
- Male
- RNA, Viral/isolation & purification
- T-Lymphocytes/pathology
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1505
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Abstract
A 68-year-old woman in whom a thoracic aortic dissection (DeBakey type III) had been followed up for 6 years was admitted to our hospital with a complaint of chest pain. A graft replacement of the descending thoracic aorta was performed. A communication between the second and third channels was detected intraoperatively. Nine cases of three-channeled aortic dissection whose third dissection existed within the outer wall of the second one were previously reported, and 4 of them had a communication between the two false channels.
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1506
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Hayashi H, Inoue K, Aung T, Tun T, Echigo Y, Gu YJ, Shinohara S, Kaji H, Kato M, Imamura M. Xenotransplantation of a novel B-cell line (MIN6) in mesh-reinforced polyvinyl alcohol hydrogel bag. Transplant Proc 1995; 27:3358-61. [PMID: 8539994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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1507
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Kato M, Bragadóttir R, Jarkman S, Nilsson SE. Effects of quisqualic acid on the corneal and intraretinal direct-current electroretinogram and on the standing potential of the rabbit eye. Doc Ophthalmol 1995; 91:349-62. [PMID: 8899305 DOI: 10.1007/bf01214653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Quisqualic acid, an excitatory amino acid agonist, has been shown to stimulate inositol phosphate production in the rabbit retina. Inositol trisphosphate serves as a second messenger and increases intracellular calcium. We investigated the influence of quisqualic acid on the direct-current electroretinogram and on the standing potential of the rabbit eye. After unilateral vitrectomy, the corneal direct-current electroretinogram and the standing potential were recorded from both eyes of albino rabbits during simultaneous unilateral intravitreal perfusion with quisqualic acid alternating with control solution. The contralateral eye was used as a control. Intravitreal perfusion with 100-microM and 200-microM quisqualic acid elevated the standing potential significantly. This elevation was accompanied by a significant increase in c-wave amplitude and a significant decrease in b-wave amplitude. Quisqualic acid at 200-microM concentration decreased the a-wave amplitude also. In vivo intraretinal recordings showed that intravitreal perfusion with quisqualic acid at 200-microM concentration significantly increased the retinal pigment epithelial component of the c-wave. We conclude that quisqualic acid influences the direct-current electroretinogram and the standing potential apparently through its action on the retinal pigment epithelium. A possible mode of action is increased production of inositol trisphosphate, followed by an increase in intracellular release of calcium ions and an increase in basal chloride conductance. The decrease in a- and b-wave amplitudes indicates direct effects of quisqualic acid also on the neural retina.
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1508
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Nishida K, Kato M, Higashijima M, Takagi K, Akashi R. [A case of Lemmel's syndrome caused by a large diverticular enterolith at the peripapillary portion of the duodenum]. Nihon Ronen Igakkai Zasshi 1995; 32:825-9. [PMID: 8865745 DOI: 10.3143/geriatrics.32.825] [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: 02/02/2023]
Abstract
A 93-year-old woman admitted because of epigastralgia. Cholelithiasis, obstructive jaundice, acute suppurative cholangitis and acute pancreatitis were diagnosed on blood chemistry and ultrasonography on admission. We performed emergency PTCD. A calculus 4 cm in diameter was detected at the papilla of Vater and marked dilatation of the common bile duct and pancreatic duct. ESWL was performed because of her age and because endoscopical operation seemed to be difficult. After lithotripsy, PTC and endoscopy demonstrated a diverticulum at the peripapillary portion of the duodenum. Based on analysis of PTC result before and after ESWL, we diagnosed this case as Lemmel's syndrome (obstructive jaundice, acute suppurative cholangitis and acute pancreatitis) caused by a large diverticular enterolith at the peripapillary portion of the duodenum. ESWL treatment of aged patient with an enterolith is safe.
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1509
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Yoshino A, Kato M. Influence of social desirability response set on self-report for assessing the outcome of treated alcoholics. Alcohol Clin Exp Res 1995; 19:1517-9. [PMID: 8749819 DOI: 10.1111/j.1530-0277.1995.tb01016.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We studied the influence of the social desirability response set on self-reporting by alcoholics on the outcome of treatment. Seventy-one treated alcoholics gave answers based on the social desirability scale (SDS) and 19 alcohol-related items designed to evaluate abstinence, and were diagnostically interviewed. The serum gamma-glutamyl-transpeptidase (GGT) level was used as an external standard to evaluate the validity of self-reporting. As SDS scores increased, both the rate of abstinence reported by the subjects and the kappa coefficient between the self-report and diagnostic interview increased. However, the GGT level was significantly low in subjects who reported abstinence than those who reported drinking, regardless of SDS score. Thus, the social desirability response set may not be associated with a conscious response bias in alcohol-related self-reports, but may be associated with a good outcome of alcoholism.
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1510
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Wada T, Kamiryo Y, Tsuchida M, Kato M. [Laparoscopic unroofing of a renal cyst]. HINYOKIKA KIYO. ACTA UROLOGICA JAPONICA 1995; 41:861-5. [PMID: 8533687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Laparoscopic unroofing of a renal cyst was performed in 13 cases of simple cysts of 48 ml. to 678 ml. (mean: 217 ml.) preoperatively measured by ultrasonography from April, 1994 through April, 1995 at our Department of Urology. Under general anesthesia, the renal cyst wall was resected as close as possible to the renal parenchyma by the laparoscopic technique. The postoperative outcome was evaluated in 12 of 13 cases, except for the one case converted to laparotomy because of uncontrollable bleeding from the resected site of the renal parenchyma. Three months after the operation, complete disappearance of the renal cyst was noted by CT scanning in 10 of the 12 cases. In the remaining 2 cases, the renal cyst was still in existence despite the apparent reduction of the cyst volume. In one case in which a somewhat large cyst remained, sclerotherapy using minocycline was carried out. No serious complications during the operation were observed, but in one case with uncontrollable bleeding as mentioned above, the postoperative course was uneventful. These findings indicate that, the laparoscopic unroofing of a renal cyst is a safe and useful procedure for a relatively large renal simple cyst, therefore this approach seems to be acceptable, and before long it will be an ordinary urological operation.
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1511
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Nagasaki Y, Iijima M, Kato M, Kataoka K. Primary amino-terminal heterobifunctional poly(ethylene oxide). Facile synthesis of poly(ethylene oxide) with a primary amino group at one end and a hydroxyl group at the other end. Bioconjug Chem 1995; 6:702-4. [PMID: 8608183 DOI: 10.1021/bc00036a007] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Well-defined poly(ethylene oxide) (PEO) with a cyano group at one end and a hydroxyl group at the other terminus was synthesized by the anionic ring opening polymerization of ethylene oxide (EO) initiated with (cyanomethyl)potassium (CMP) which was prepared by the metalation reaction of acetonitrile with potassium naphthalene in THF. Primary amino-terminal heterotelechelic PEO was obtained by the reduction of the cyano group at the end of the polymer chain by lithium aluminum hydride.
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1512
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Kato M, Fujiwara Y, Okamoto A, Yoshikawa M, Chiba H, Udaka S. Efficient production of casoxin D, a bradykinin agonist peptide derived from human casein, by Bacillus brevis. Biosci Biotechnol Biochem 1995; 59:2056-9. [PMID: 8541641 DOI: 10.1271/bbb.59.2056] [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: 01/31/2023]
Abstract
We efficiently produced a small peptide by the host-vector system using Bacillus brevis as a host. DNA encoding the physiologically functional casoxin D, composed of seven amino acids, was ligated in tandem. An expression-secretion vector containing DNA, which codes for a fusion protein of epidermal growth factor-casoxin D pentamer, was constructed. B. brevis transformed with this plasmid produced about 0.5 g/liter of the fusion protein in the culture supernatant. The fusion protein was purified with ammonium sulfate fractionation from the supernatant and digested with two kinds of proteinases. A peptide well separated by high pressure liquid chromatography was identified as biologically active casoxin D.
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1513
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Kato M, Bai H, Sato K, Kawamoto S, Kaneko M, Ueda T, Kishi D, Ohnishi K. Determining surgical indications for acute type B dissection based on enlargement of aortic diameter during the chronic phase. Circulation 1995; 92:II107-12. [PMID: 7586392 DOI: 10.1161/01.cir.92.9.107] [Citation(s) in RCA: 142] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND In patients with Stanford type B dissection who have been treated successfully with medical hypotensive therapy during the acute phase, a large number have incurred the risk of surgery during their chronic phases because of enlargement of the dissected aorta. The purpose of this study was to determine the indications for surgical treatment of acute type B dissection by studying chronic-phase enlargements of aortic dissections in patients treated successfully with medical hypotensive therapy during the acute phase. METHODS AND RESULTS In 41 patients with type B dissection who had been treated medically during the acute phase, univariate and multivariate factor analyses were made to determine the predominant predictors for chronic-phase enlargement (> or = 60 mm) of the dissected aorta. Computed tomography was performed every 4 to 14 months to observe whether there was enlargement of the maximum aortic diameter. The predominant predictors for aortic enlargement in the chronic phase were the existence of a maximum aortic diameter of > or = 40 mm during the acute phase (P < .001) and a patent primary entry site in the thoracic aorta (P = .001). The values of actuarial freedom from aortic enlargement for the patients with a large aortic diameter (> or = 40 mm) during the acute phase and a patent primary entry site in the thorax at 1, 3, and 5 years were 70%, 29%, and 22%, respectively. No aortic enlargement was observed in the other patients throughout the entire follow-up period. CONCLUSIONS These data suggest that patients with acute type B dissection who have a large aortic diameter (> or = 40 mm) and a patent primary entry site in the thorax should be treated surgically during the acute phase on the condition that the surgical risk in this phase is limited.
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1514
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Abstract
It is known that withdrawal of somatostatin (SRIF) augments the growth hormone (GH) releasing hormone (GRF)-induced GH secretion. To investigate the mechanism of this augmentation in GH secretion, effects of GRF and SRIF on L-type Ca2+ current (Ba2+ was used as a charge carrier) or primary cultured rat somatotroph were studied by perforated patch clamp technique. The reason is that GRF-induced GH secretion is thought to be causally related to the influx of Ca2+ through L-type Ca2+ channels. 10 mM GRF augmented maximum amplitude of L-type Ba2+ current by 12.2% (n = 12). Subsequent application of SRIF slightly suppressed the currents but the suppression never exceeded the control level of the current. Removal of SRIF, however, promptly augmented the L-type Ba2+ current by 26.8%. Such off-response of SRIF was not observed in cells treated overnight with 100 ng/ml pertussis toxin. Further, specific inhibitor of protein kinase A, H-89 at 1 microM reversibly suppressed the augmentation of L-type Ba2+ current to control level. At 10 microM, H-89 suppressed L-type Ba2+ current by more than 40% from control level. These results suggest that (1) L-type Ca2+ channel of somatotroph is probably phosphorylated in a basal condition and may be slightly modulated by GRF through increased level of cAMP; (2) SRIF only slightly suppress the channel activity; (3) Withdrawal of SRIF facilitates the activity of L-type Ca2+ channel via PTX-sensitive G-protein, although the precise mechanism of this facilitation is unknown. The augmentation by SRIF-pretreatment of GRF-induced GH secretion may be at least partly due to the facilitation of the activity of L-type Ca2+ channel.
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1515
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Miyakoda H, Kato M, Noguchi N, Omodani H, Osaki S, Matsumoto T, Kinugawa T, Hoshio A, Kotake H, Mashiba H. Exercise-induced ST-segment elevation--role of left ventricular wall motion abnormalities and coronary artery narrowing. JAPANESE CIRCULATION JOURNAL 1995; 59:725-35. [PMID: 8747762 DOI: 10.1253/jcj.59.725] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We studied the causes of exercise-induced ST-segment elevation. Group I consisted of 15 patients with anterior myocardial infarction in the absence of a coronary artery luminal narrowing of 75% or more. Group II consisted of 36 patients with predominantly exertional angina and a luminal narrowing of 90% or more in the left anterior descending coronary artery in the absence of previous myocardial infarction. In group I, exercise-induced ST-segment elevation occurred frequently during treadmill exercise (15/15, 100%). None of the patients showed 201Tl redistribution. The standard deviation of the phase in radionuclide ventriculography increased during bicycle exercise. Of group II patients, only those with 99% narrowing and poor collaterals showed exercise-induced ST-segment elevation (13/14, 93%), whereas none of those with complete occlusion or 99% narrowing and good collaterals, or 90% narrowing showed ST-segment elevation. In group II, patients with exercise-induced ST-segment elevation showed lower 201Tl uptake during exercise and washout in the territory of the diseased vessel than those without exercise-induced ST-segment elevation. In conclusion, wall motion abnormalities may cause exercise-induced ST-segment elevation independently of myocardial ischemia. In patients with predominantly exertional angina, exercise-induced ST-segment elevation may be a marker for 99% narrowing with poor collaterals and severe myocardial ischemia.
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1516
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Jiang R, Kato M, Bernfield M, Grabel LB. Expression of syndecan-1 changes during the differentiation of visceral and parietal endoderm from murine F9 teratocarcinoma cells. Differentiation 1995; 59:225-33. [PMID: 8575644 DOI: 10.1046/j.1432-0436.1995.5940225.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
F9 teratocarcinoma stem cells treated with retinoic acid differentiate in suspension into embryoid bodies with an outer layer of visceral endoderm surrounding a core of largely undifferentiated cells. The visceral endoderm-containing embryoid bodies, when plated onto an extracellular matrix coating, give rise to parietal endoderm outgrowth. These in vitro cell cultures mimic both geometrically and biochemically the differentiation of visceral and parietal endoderm in the early mouse embryo and, thus, were used as a model system for the study of molecular and cellular mechanisms underlying the differentiation of the extraembryonic endoderm lineages. We have investigated the expression of syndecan-1, an integral membrane proteoglycan that binds to multiple components of the extracellular matrix and basic FGF, during visceral endoderm differentiation and parietal endoderm outgrowth. Syndecan-1 immunostaining is detected on all cell surfaces in the undifferentiated embryoid bodies and in the differentiating embryoid bodies prior to the formation of the visceral endoderm. Following the differentiation of visceral endoderm, syndecan-1 localizes predominantly to the basal surface of this epithelial layer, while syndecan-1 staining in the core of differentiated embryoid bodies is faint. Quantitation of cell associated syndecan-1 indicates that syndecan-1 is down-regulated during embryoid body differentiation. However, northern analysis shows that the amounts of steady-state syndecan-1 mRNA are the same in undifferentiated versus differentiated embryoid bodies, suggesting post-transcriptional regulation of syndecan-1 expression in the differentiating embryoid body. Analysis of syndecan-1 distribution in the outgrowth culture by immunofluorescence demonstrates that syndecan-1 is absent from the cell surface of parietal endoderm. However, a substantial amount of syndecan-1 is detected inside parietal endoderm cells. While all three cell types release syndecan-1 ectodomain into the culture medium, the parietal endoderm outgrowth releases more syndecan-1 ectodomain than the differentiated embryoid body. These data suggest that the post-transcriptional control and post-translational shedding of syndecan-1 from the cell surface are developmentally regulated during the differentiation of visceral to parietal endoderm and the migration of parietal endoderm.
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1517
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Kato M, Mizuguchi M, Takashima S. Developmental changes of epidermal growth factor-like immunoreactivity in the human fetal brain. J Neurosci Res 1995; 42:486-92. [PMID: 8568935 DOI: 10.1002/jnr.490420407] [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: 01/31/2023]
Abstract
We investigated the immunohistochemical localization of epidermal growth factor (EGF) in the developing human brain from 6 weeks of gestation to 3 months postpartum. EGF-like immunoreactivity varied in its localization and intensity according to the stage of development. At 10 - 20 weeks of gestation, EGF-like immunoreactivity appeared in proliferating and migrating cells in the cerebrum, disappeared thereafter, and appeared again in cortical neurons after 27 weeks of gestation. Astrocytes also showed EGF-like immunoreactivity from 27 weeks of gestation. These results suggest developmental regulation of EGF expression in the human brain, suggesting its physiological role in both neuronal and glial cells.
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1518
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Kato M, Funahashi H, Sato Y, Takagi H. [Parathyroid transplants in dogs]. NIHON GEKA GAKKAI ZASSHI 1995; 96:766-72. [PMID: 8569677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Autotransplantation of the parathyroid glands by mincing method has been performed to maintain parathyroidal function in patients with thyroid cancer, following total thyroidectomy and parathyroidectomy. The functional recovery of grafted parathyroid glands was studied in matured mongrel dogs histologically and by determining the PTH level and serum P, Ca, and compared three different forms of implant; whole gland, minced parathyroid tissue, and thick slices. The minced parathyroid tissue and thick slices were found to be far superior histologically, and endocrinologically, to the whole gland type of implant, with successful takes. And between two types of implants minced tissue and thick slices, no difference was observed histologically and endocrinologically. On the other hand, it is necessary for shortening the time to prepare implant tissue to get successful reimplantation. The time to prepare minced tissue is very short in comparison with thick slices. Thus our method (minced tissue) is very useful for successful reimplantation of the parathyroids.
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1519
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Wakimoto A, Ohashi K, Koyama M, Kato M, Tsutsui T, Saji F, Tanizawa O. Regulation of classical HLA class I genes in human choriocarcinoma cells by nuclear proteins binding to MHC class I regulatory elements. Am J Reprod Immunol 1995; 34:323-31. [PMID: 8595132 DOI: 10.1111/j.1600-0897.1995.tb00959.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
PROBLEM The regulation of classical HLA class I genes in choriocarcinoma have been reported. METHODS We determined whether four choriocarcinoma cell lines expressed classical HLA class I or HLA-G by a reverse transcription-polymerase chain reaction (RT-PCR) and studied the regulatory mechanism of classical class I using a gel mobility shift assay. RESULTS NUC1 and SCH expressed classical class I but not HLA-G. GCH1 and Jar did neither. Nuclear protein binding to the class I regulatory element (CRE) was detected in NUC1 and SCH. Interferon-gamma augmented both classical class I expression and the DNA-protein complex in NUC1. The DNA-protein complex was not observed in GCH1, and Jar showed a CRE-binding protein with different electrophoretic mobility and binding affinity from that of SCH and NUC1. CONCLUSION The CRE is one of the regulatory elements of classical HLA class I genes in choriocarcinoma cells.
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1520
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Senokuchi K, Nakai H, Nakayama Y, Odagaki Y, Sakaki K, Kato M, Maruyama T, Miyazaki T, Ito H, Kamiyasu K. New orally active serine protease inhibitors: structural requirements for their good oral activity. J Med Chem 1995; 38:4508-17. [PMID: 7473579 DOI: 10.1021/jm00022a017] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Synthesis and structural requirements for good oral activity of a series of para-substituted benzoyl esters of 4-hydroxybenzamidine serine protease inhibitors are described. The structure required for good oral activity was found to be general formula II whose corresponding ester has to be hydrolyzed in the intestine before absorption through the mucous membranes or in plasma after absorption. Biological evaluation of oral absorption using plasma anti-trypsin activity was useful for rapid evaluation. By measuring their actual plasma concentrations after oral administration, compounds 14 and 16b were confirmed to show good area under the plasma concentration-time curves (AUC). Their plasma concentrations corresponded to their plasma anti-trypsin activity. Structure-oral activity relationships are discussed.
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1521
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Nishimura T, Akiyama H, Yonehara S, Kondo H, Ikeda K, Kato M, Iseki E, Kosaka K. Fas antigen expression in brains of patients with Alzheimer-type dementia. Brain Res 1995; 695:137-45. [PMID: 8556323 DOI: 10.1016/0006-8993(95)00699-q] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Fas antigen (CD95) is a cell surface protein that mediates apoptosis. We have investigated the immunohistochemical localization of Fas antigen in postmortem brain tissue from control subjects, patients with Alzheimer-type dementia (ATD), and from a few patients with diffuse Lewy body disease, progressive supranuclear palsy and adrenoleukodystrophy. In all brains, including controls, vascular endothelial cells and residual blood plasma were weakly stained. In ATD brains, senile plaques and a small number of star-like cells were brains of patients with neurological diseases other than ATD. In double immunostaining for Fas and glial fibrillary acidic protein (GFAP), a small number of cells were positive for both antigens. The majority of Fas-positive astrocytes were, however, negative for GFAP. This implies the downregulation of GFAP production in these cells. Doubly labeled astrocytes were also found around senile plaques, suggesting that the Fas immunoreactivity in senile plaques was derived from astrocytic membranes. The results of this study indicate that Fas antigen is expressed by a subset of reactive astrocytes in degenerative neurological diseases. Such astrocytes may undergo the Fas-mediated apoptotic process.
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1522
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Hashimoto Y, Iwase Y, Mogami T, Hayashi Y, Sasaki S, Kato M, Tugaya M, Kohri K. [A case of adult pure yolk sac tumor of the testis achieving pathological complete response by chemotherapy]. HINYOKIKA KIYO. ACTA UROLOGICA JAPONICA 1995; 41:813-6. [PMID: 8533681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We report a case of pure yolk sac tumor of the left testis in a 22-year-old male. He consulted a physician with left back pain and induration of his left scrotal content in December, 1992. Intravenous pyelography (IVP) revealed left hydronephrosis. Computerized tomography (CT) revealed para-aortic lymph node swelling and lung metastases. Left high inguinal orchiectomy was performed. Histopathological diagnosis was pure yolk sac tumor. After two courses of "COMPE" chemotherapy consisting of cisplatin, vincristine, methotrexate, peplomycin and etoposide, two courses of "high dose "COMPE" chemotherapy and three courses of "high dose COME" chemotherapy without peplomycin, he achieved a partial response (the regression rate of the pulmonary metastases and the retroperitoneal lymph node metastasis were 100% and 96.0% on CT, respectively) and the residual masses in the retroperitoneum were removed. Necrosis and xanthogranulomatous fibrosis were found in the resected material. The patient showed no evidence of disease two years after chemotherapy.
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1523
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Hashimoto S, Kato M, Dong Y, Terada S, Inoue M. [Effect of sex steroids on serum amyloid P-component (female protein) in rats]. NIHON SANKA FUJINKA GAKKAI ZASSHI 1995; 47:1041-1047. [PMID: 8522881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Serum amyloid P-component (SAP) has been designated as a female protein in hamsters. But such a distinction is not made for rats. In order to investigate the effects of sex-steroids on the SAP level in rats, SAP was purified from Wistar rats by affinity chromatography of phosphorylcholine, followed by gel filtration. Anti-SAP was raised through the immunization of rabbits with the rat SAP and Freund's adjuvant. Sample sera were obtained from 180 young and old rats, after which rats were injected with estradiol (E2), testosterone (T) or dehydroepiandrosterone (DHEA). Sera were serially obtained from the tail vessels until the 8th day after injection. The SAP level was assayed by micro single radial immunodiffusion. As the rats aged, the SAP levels increased from 2.9 mg/dl at 11 weeks to 10.7mg/dl at 58 weeks. In 37-week-old rats, the SAP levels in females (6.3 +/- 1.8 mg/dl) were significantly (p < 0.001) higher than those in males (3.9 +/- 1.0 mg/dl). The SAP levels did not change after T administration, but were increased rapidly by E2 administration, especially in young male rats (increased from 2.6 +/- 0.2 mg/dl to 4.9 +/- 0.7 mg/dl). The SAP levels were decreased significantly (p < 0.05) by DHEA injection. Serum E2 levels in young (11 wk) male rats were very low before E2 injection, and rose steeply on the 2nd day. From these findings, the different SAP levels in mature female and male rats are attributed to E2.
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1524
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Komatsu M, Shimizu H, Tsuruta T, Kato M, Fushimi T, Inoue K, Kobayashi S, Kuroda T. Effect of lithium on serum calcium level and parathyroid function in manic-depressive patients. Endocr J 1995; 42:691-5. [PMID: 8574294 DOI: 10.1507/endocrj.42.691] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The purpose of this study is to find out whether hypercalcemia and hyperparathyroidism are rare or not in manic-depressive patients taking lithium carbonate. The subjects were 13 patients receiving lithium and 19 healthy subjects not receiving it as normal controls. Serum ionized calcium (Ca++), serum parathyroid hormone (PTH), urinary calcium and cyclic AMP(cAMP) were measured. Cervical ultrasonographic examination was also performed. The mean serum Ca++ level in the lithium administered group was significantly higher than that in the control group (P < 0.02). There was no significant difference between the serum PTH levels in the two groups. The mean urinary calcium level in the lithium administered group was below the normal range, but the mean urinary of cAMP level was within the normal range. Although a parathyroid cyst was found in one lithium administered patient on ultrasonographic examination, no swelling of the parathyroid gland was observed in the other patients in the lithium administered group or in any of the control subjects. In the present study, no distinct hyperparathyroidism was found in the patients in the lithium administered group. Lithium administration affects calcium metabolism in manic-depressive patients and hypercalcemia seems to be one of the complications needing attention at the time of lithium administration.
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1525
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Kuroda K, Miyata K, Shikama H, Kawagoe T, Nishimura K, Takeda K, Sakae N, Kato M. Novel muteins of human tumor necrosis factor with potent antitumor activity and less lethal toxicity in mice. Int J Cancer 1995; 63:152-7. [PMID: 7558445 DOI: 10.1002/ijc.2910630127] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Eight muteins of recombinant human tumor necrosis factor-alpha (rhTNF; 1SSSRTP...29RR...155L), in which 29Arg was replaced by another amino acid, were prepared and their anti-tumor effects in BALB/c mice bearing Meth A fibrosarcoma were evaluated. The therapeutic indices, which mark the extent of the therapeutically effective dose, of V29 (29Arg-->Val) and D29 (-->Asp) were 3.5 and 3.2, respectively, whereas that of rhTNF was 1.4. Clearly, the therapeutically effective range of these muteins was extended along with a decrease in lethal toxicity. V29 did not produce hypotension in the rat system, but D29 did. In addition, V29 showed potent anti-tumor activity (Tumor Volume Inhibition Rate = 81% on day 15 after implantation) in 3 consecutive injection schedules despite the decreases in toxicity compared with rhTNF. The relative receptor binding constant was determined using HEp-2 cells (expressing mainly 55-kDa-TNF receptor; p55R) and HL60 cells (expressing mainly 75-kDa-TNF receptor; p75R), and revealed that the reduced toxicity of V29 in mice was due to the reduced binding to p55R (34% of rhTNF). On the other hand, the ratio of the constants HEp-2/HL60 of V29 was 11 in comparison with the value of 1.0 for rhTNF, suggesting that this mutein binds preferentially to p55R. The biological activities in human cell lines (HEp-2 and HL60 cells) correlated well with the binding activities to each receptor in vitro. Therefore, the much lower toxicity and the potent anti-tumor activity of this mutein suggest that V29 merits further investigation in pre-clinical and clinical trials.
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