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Koda Y, Nakamura K, Kaminou T, Osugi H, Nakata M, Hamuro M, Hayashi S, Takashima S, Higashino M, Yamada R. Assessment of aortic invasion by esophageal carcinoma using intraaortic endovascular sonography. AJR Am J Roentgenol 1998; 170:133-5. [PMID: 9423617 DOI: 10.2214/ajr.170.1.9423617] [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: 02/05/2023]
Abstract
OBJECTIVE Accurate preoperative assessment of aortic invasion by esophageal carcinoma is of great importance for planning surgery. We compared the accuracy of intraaortic endovascular sonography with that of CT in the diagnosis of aortic invasion by esophageal carcinoma. CONCLUSION In this study, intraaortic endovascular sonography was sensitive in detecting aortic invasion; both sensitivity and specificity were 100%. Intraaortic endovascular sonography proved useful in detecting aortic invasion by esophageal carcinoma.
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Nagano T, Oyama Y, Kajita N, Chikahisa L, Nakata M, Okazaki E, Masuda T. New curcuminoids isolated from Zingiber cassumunar protect cells suffering from oxidative stress: a flow-cytometric study using rat thymocytes and H2O2. JAPANESE JOURNAL OF PHARMACOLOGY 1997; 75:363-70. [PMID: 9469642 DOI: 10.1254/jjp.75.363] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Effects of new complex curcuminoids (cassumunin A and cassumunin B) isolated from tropical ginger, Zingiber cassumunar, were examined in dissociated rat thymocytes suffering from oxidative stress induced by 3 mM hydrogen peroxide by using a flow cytometer and ethidium bromide. The effects were compared with those of curcumin, a natural antioxidant, whose chemical structure is included in those of cassumunins A and B. Pretreatment of rat thymocytes with the respective cassumunins at concentrations ranging from 100 nM to 3 microM dose-dependently prevented the hydrogen peroxide (H2O2)-induced decrease in cell viability. It had the same action, although less effective, against the treatment with cassumunin A or B (3 microM) immediately after or 60 min after start of the oxidative stress. Respective potencies of cassumunins A and B in protecting the cells suffering from H2O2-induced oxidative stress were greater than that of curcumin. It is suggested that cassumunins A and B may possess a potent protective action on living cells suffering from oxidative stress.
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Yada T, Sakurada M, Ishihara H, Nakata M, Shioda S, Yaekura K, Hamakawa N, Yanagida K, Kikuchi M, Oka Y. Pituitary adenylate cyclase-activating polypeptide (PACAP) is an islet substance serving as an intra-islet amplifier of glucose-induced insulin secretion in rats. J Physiol 1997; 505 ( Pt 2):319-28. [PMID: 9423175 PMCID: PMC1160066 DOI: 10.1111/j.1469-7793.1997.319bb.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
1. We examined whether pituitary adenylate cyclase-activating polypeptide with 38 or 27 residues (PACAP-38 or PACAP-27) serves as an intra-islet regulator of glucose-induced insulin secretion in rats. PACAP antiserum specific for PACAP-38 and PACAP-27 was used to neutralize the effect of endogenous PACAP in islets. PACAP release from islets was bioassayed using the response of cytosolic Ca2+ concentration ([Ca2+]i) in single beta-cells, monitored by dual-wavelength fura-2 microfluorometry. Expression of PACAP mRNA was studied by reverse transcription-polymerase chain reaction (RT-PCR), while expression of PACAP was studied by metabolic labelling and immunoblotting. Localization of PACAP receptors was studied immunohistochemically. 2. High glucose-stimulated insulin release from isolated islets was attenuated by PACAP antiserum but not by non-immune sera. 3. The islet incubation medium with high glucose (Med) possessed a capacity, which was neutralized by PACAP antiserum, to increase [Ca2+]i in beta-cells. PACAP antiserum also neutralized the [Ca2+]i-increasing action of synthetic PACAP-38 and PACAP-27, but not that of vasoactive intestinal polypeptide (VIP) and glucagon. 4. Both Med and synthetic PACAP increased [Ca2+]i in beta-cells only in the presence of stimulatory, but not basal, glucose concentrations. In contrast, ATP, a substance that is known to be released from beta-cells, increased [Ca2+]i in beta-cells at both and stimulatory glucose concentrations. 5. Expression of PACAP mRNA and biosynthesis of PACAP-38 were detected in islets and a beta-cell line, MIN6. 6. Immunoreactivity for PACAP-selective type-I receptor was observed in islets. 7. [Ca2+]i measurements combined with immunocytochemistry with insulin antiserum revealed a substantial population of glucose-unresponsive beta-cells, many of which were recruited by PACAP-38 into [Ca2+]i responses. 8. These results indicate that PACAP-38 is a novel islet substance that is synthesized and released by islet cells and then, in an autocrine and/or paracrine manner, potentiates and arouses beta-cell responses to glucose, thereby amplifying glucose-induced insulin secretion in islets.
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Yamakuchi M, Nakata M, Kawahara K, Kitajima I, Maruyama I. New quinolones, ofloxacin and levofloxacin, inhibit telomerase activity in transitional cell carcinoma cell lines. Cancer Lett 1997; 119:213-9. [PMID: 9570374 DOI: 10.1016/s0304-3835(97)00269-3] [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: 02/07/2023]
Abstract
It has been demonstrated that some quinolone antibiotics inhibit cell proliferation in vitro. This study showed that ofloxacin and levofloxacin, two well-known new quinolones, had an inhibitory effect on the proliferation of transitional cell carcinoma cell lines at high concentrations (>200 microg/ml). At relatively low concentrations (10-100 microg/ml), however, there was no apparent antiproliferative effect. Despite this, decreased absorbance in the MTT assay was observed at low concentrations and telomerase activity was significantly decreased. These results suggest that the antiproliferative effect of both ofloxacin and levofloxacin may be related to impairment of telomerase activity by some unknown mechanism.
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Yada T, Nakata M. [Molecular mechanisms for impaired insulin secretion in NIDDM]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 1997; 55 Suppl:320-7. [PMID: 9392127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Nasuda-Kouyama A, Nakata M, Iizuka T, Isogai Y. Mechanisms of nitroso compound-induced inhibition of superoxide generation in neutrophils: fluorescence quenching of perylene by nitroso-compounds in the membrane fractions of neutrophils. J Biochem 1997; 122:550-5. [PMID: 9348083 DOI: 10.1093/oxfordjournals.jbchem.a021788] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
To investigate the mechanism of nitroso compound-induced inhibition of the respiratory burst in neutrophils, we studied fluorescence quenching of perylene by nitroso-compounds in the membrane fractions of neutrophils at 17, 27, and 37 degrees C and the reagent-induced inhibition of superoxide generation at 28 and 37 degrees C. With increasing temperature, the quenching of perylene fluorescence and inhibition of superoxide generation by nitrosobenzene (NB) were both diminished, while those by 2-nitrosotoluene (NT) were both enhanced. The temperature dependence of the inhibition constants and the quenching constants indicates that the binding of NB is exothermic (deltaH= -27 kJ/mol for inhibition and deltaH= -29 kJ/mol for quenching) and essentially enthalpy-driven. On the other hand, that of NT is endothermic (deltaH= +16 kJ/mol for inhibition and quenching) and essentially entropy-driven. Quenching studies of perylene fluorescence in synthetic vesicles made of endogenous polar lipids of neutrophils showed that the enthalpy changes of NB- and NT-binding with perylene in lipids were similar to each other. Moreover, their values were in good agreement with that of NT, but not of NB, in the membrane fractions, an assembly of proteins and lipids, of neutrophils. These results suggest that NB inhibits the activity by binding to proteins in the membrane, whereas inhibition by NT occurs through hydrophobic interaction with lipids and/or proteins.
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Tatsumi E, Nakamura M, Masuzawa T, Taenaka Y, Sohn YS, Nishimura T, Nakata M, Nakatani T, Ohno T, Endo S, Takiura K, Takewa Y, Kakuta Y, Takano H. In vitro and in vivo evaluation of a left-right balancing capacity of an interatrial shunt in an electrohydraulic total artificial heart system. ASAIO J 1997; 43:M619-25. [PMID: 9360119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The authors evaluated the basic performance of an interatrial shunt (IAS) made by punching a hole in the atrial septum, in accommodating the left-right imbalance in our electrohydraulic total artificial heart (EHTAH) system. In an in vitro study conducted in a closed mock circuit connected with the EHTAH, the interatrial pressure gradient changed in compliance with the amount of bronchial flow and the size of the IAS. The IAS of 4.4 mm diameter or larger maintained the interatrial pressure gradient within physiologically permissible limits when the amount of bronchial flow was 5% of cardiac output or less. A left-to-right one-way valve made of a piece of pericardium, a possible option in this IAS method, successfully prevented right-to-left reverse shunt flow through the IAS. In a chronic in vivo study using a calf implanted with the EHTAH for 10 days, a 4.5 mm IAS without the one-way valve demonstrated satisfactory dynamic left-right balancing capacity with a stable interatrial pressure gradient of 4 +/- 1 mmHg over a wide range of atrial pressures. No thrombus was found in or around the IAS at autopsy. The authors conclude that the IAS is a simple and promising means of left-right balancing in the EHTAH system.
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Nakata M, Ohki M. [Cancer and fusion gene]. TANPAKUSHITSU KAKUSAN KOSO. PROTEIN, NUCLEIC ACID, ENZYME 1997; 42:1978-90. [PMID: 9301327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Nakata M, Saeki H, Takashima S. 285 Clinical stage I non-small cell lung cancer: An analysis of prognostic factors and a reconsideration of treatments. Lung Cancer 1997. [DOI: 10.1016/s0169-5002(97)89667-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Sai Htay W, Nonaka K, Sasaki Y, Nakata M. A longitudinal study of the postnatal maternal effect on the craniofacial growth of mouse offspring by cross-nursing. JOURNAL OF CRANIOFACIAL GENETICS AND DEVELOPMENTAL BIOLOGY 1997; 17:148-159. [PMID: 9338858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A cross-nursing experiment was conducted to examine the nursing dam strain effect on the postnatal growth of a newborn mouse offspring by simultaneously using larger DDD strain mice and smaller C57BL strain ones. A periodical cephalometric observation of the postnatal craniofacial growth of the offspring was longitudinally made from birth up to the 100th day of life in addition to measuring the offspring weight. According to multivariate statistical analyses, the following results were obtained: 1) The mean body weight of the DDD offspring cross-nursed by the C57BL dam was significantly lighter than that of the DDD offspring self-nursed by the DDD dam throughout the whole experimental period except at birth and on the 100th day. 2) The mean body weight of the C57BL offspring cross-nursed by the DDD dam was significantly heavier than that of the C57BL offspring self-nursed by the C57BL dam from the 10th day up to the 30th day. 3) There was a significant positive relationship between the offspring weight and the offspring craniofacial size throughout the entire experimental period in the C57BL offspring and from the 10th day up to the 40th day in the DDD offspring. 4) The nursing dam strain effect on the craniofacial size of the DDD offspring was also significant on the 30th, 60th, 80th, and 100th days. The adjusted craniofacial size of the DDD offspring cross-nursed by the C57BL dam was significantly smaller than that of the DDD offspring self-nursed by the DDD dam on the 30th, 60th, 80th, and 100th days. 5) The nursing dam strain effect on the craniofacial size of the C57BL offspring was not significant throughout the whole experimental period. The adjusted craniofacial size of the C57BL offspring cross-nursed by the DDD dam was almost the same as that of the C57BL offspring self-nursed by the C57BL dam throughout the whole experimental period. 6) The fat content of the DDD dam tended to be higher than that of the C57BL dam and the interstrain difference was closed to a significant level (P = 0.06) on the 20th day. The moisture content of the DDD dam tended to be lower than that of the C57BL dam and the interstrain difference was also significant on the 7th day (P < 0.001). Based on these findings, it can thus be concluded that the nursing dam strain effect played an important role in the postnatal somatic growth of the DDD and the C57BL offspring and the craniofacial growth and the DDD offspring.
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Nakata M, Nasuda-Kouyama A, Isogai Y, Kanegasaki S, Iizuka T. Effect of aromatic nitroso-compounds on superoxide-generating activity in neutrophils. J Biochem 1997; 122:188-92. [PMID: 9276687 DOI: 10.1093/oxfordjournals.jbchem.a021727] [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: 02/05/2023] Open
Abstract
Aromatic nitroso-compounds such as nitrosobenzene inhibited the respiratory burst of intact neutrophils induced by various stimulants, including phorbol 12-myristate 13-acetate and a chemotactic peptide. The compounds also inhibited NADPH-dependent oxygen consumption by cell-free preparations of neutrophils. This indicates that nitroso-compounds act directly on the NADPH-oxidase system. The inhibitory effects induced by several nitroso-compounds, 2-nitrosotoluene, nitrosobenzene, 4-nitrosophenol, and 1-nitrosopyrrolidine, were examined and their inhibition constants, the concentrations causing 50% reduction of oxygen consumption, were found to be 0.043, 0.173, 0.672, and 32.1 mM, respectively. These values correlated well with the hydrophobicity of the compounds: a more hydrophobic compound was a more potent inhibitor against NADPH oxidase, suggesting that the oxidase has a hydrophobic site(s) for interaction with the inhibitors.
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Nonaka K, Sasaki Y, Watanabe Y, Yanagita K, Nakata M. Effects of fetus weight, dam strain, dam weight, and litter size on the craniofacial morphogenesis of CL/Fr mouse fetuses affected with cleft lip and palate. Cleft Palate Craniofac J 1997; 34:325-30. [PMID: 9257023 DOI: 10.1597/1545-1569_1997_034_0325_eofwds_2.3.co_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
OBJECTIVE This study examined the factors related to the morphogenesis of the craniofacial complex of the CL/Fr mouse fetus affected with CLP based on the findings of a lateral cephalogram. DESIGN Embryo transfer experiments were performed to determine the effect of the fetus weight, dam strain, dam weight, and litter size on the Intra-uterine craniofacial morphogenesis of CL/Fr mouse fetuses. On the 18th gestational day, each pregnant dam that had received CL/Fr mouse embryos was laparotomized to remove the transferred fetuses that had developed in the uteri of the cleft lip and palate (CLP)-susceptible CL/Fr strain dam and the CLP-resistant C57BL strain dam. A cephalometric observation of the craniofacial morphology of each fetus was subsequently performed. RESULTS Based on a multiple regression analysis, the standardized partial regression coefficients of the affected fetus weight, the dam weight, and the litter size on the maxillary size of the affected CL/Fr fetus were 0.71 (p < .01), 0.03, and -0.07. According to a least-squares analysis of variance, the dam strain effect in addition to the effect of the affected fetus weight on the maxillary size and the cranial size of the affected fetuses was significant (p < .01 for cranial size, p < .05 for maxillary size) and close to a significant level (p = .09) for the mandibular size of the affected fetuses. The adjusted maxillary size and cranial size after statistically eliminating the effects of the affected fetus weight, dam weight, and litter size on each original craniofacial size of the affected fetuses that had developed in the CL/Fr dam strain were also significantly smaller than those of the affected fetuses that had developed in the C57BL dam strain. CONCLUSIONS The present results indicate that the craniofacial growth of the CL/Fr mouse fetus affected with CLP increased in proportion to the fetus weight. The dam strain effect, in addition to the effect of the affected fetus weight, could thus not be ignored when the etiology of the spontaneous CLP was examined, while the uterine environment, provided by the CL/Fr strain dam, retarded the intra-uterine craniofacial growth of the affected fetuses. It was therefore concluded that the dam strain effect, as well as the effect of the affected fetus weight, both play an important role on the craniofacial morphogenesis of the CL/Fr strain of the affected fetuses that developed in both strain dams.
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Nakata M, Yada T, Nakagawa S, Kobayashi K, Maruyama I. Citrulline-argininosuccinate-arginine cycle coupled to Ca2+-signaling in rat pancreatic beta-cells. Biochem Biophys Res Commun 1997; 235:619-24. [PMID: 9207208 DOI: 10.1006/bbrc.1997.6854] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Pancreatic beta-cells possess nitric oxide (NO) synthases (NOSs) which synthesize NO and L-citrulline from L-arginine. The present study was designed to explore the mechanism of citrulline and arginine metabolism in beta-cells and its possible coupling to beta-cell functions. The enzymes involved in citrulline-arginine metabolism, argininosuccinate synthetase (ASS), argininosuccinate lyase (ASL), and NOS were expressed in rat islets and insulinoma HIT T15 cells. In the presence of stimulatory glucose, L-citrulline and L-argininosuccinate at physiological concentrations (0.1-1 mM) increased cytosolic Ca2+ concentration ([Ca2+]i) in rat beta-cells. The citrulline-induced [Ca2+]i increase was inhibited by a NOS inhibitor, N(G)-monomethyl-L-arginine (NMMA). L-citrulline also stimulated NO production in HIT cells, which was inhibited by NMMA. In conclusion, L-citrulline is metabolized by ASS-ASL-NOS cycle to produce NO, which in turn increases [Ca2+]i in beta-cells.
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Nakata M, Matsuno Y, Takenaka T, Kobayashi Y, Takeyama K, Yokozawa T, Tobinai K. B-cell lymphoma accompanying monoclonal macroglobulinemia with features suggesting marginal zone B-cell lymphoma. Int J Hematol 1997; 65:405-11. [PMID: 9195780 DOI: 10.1016/s0925-5710(96)00565-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Waldenstroem's macroglobulinemia is usually closely related to a histopathologic subtype called lymphoplasmacytoid lymphoma in the Revised European-American Lymphoma (REAL) classification. Here, we report a case of B-cell lymphoma accompanied by monoclonal macroglobulinemia and pathologically compatible with marginal zone B-cell lymphoma (MZBCL) rather than lymphoplasmacytoid lymphoma. The patient was a 74-year-old man with lymphomatous lesions that were recognized as submandibular lymphadenopathy, subcutaneous tumor and bilateral orbital masses, but with no bone marrow involvement. The atypical lymphoid cells that occupied the lymph node were varied such as small cells harboring irregular nuclei, monocytoid B-cells, large cells with vesicular nuclei, and plasma cells. The tumor cells expressed CD19, CD20, IgM and kappa on their cell surfaces and cytoplasmic IgM, but not CD5 or CD10. These findings suggest that the clinical and histopathologic findings of this case are compatible with those of MZBCL rather than lymphoplasmacytoid lymphoma. Serum IgM was elevated up to 4080 mg/dl and M-proteinemia of IgM-kappa type was confirmed by immunoelectrophoresis. Hyperviscosity syndrome caused by monoclonal IgM was not apparent. Immunohistochemical study confirmed that monoclonal IgM-kappa was produced and secreted from the tumor cells of MZBCL. This case suggests a close relationship between MZBCL and lymphoplasmacytoid lymphoma, from the perspective of the cellular origin during B-cell differentiation.
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Makino K, Kuwahara H, Masuko N, Nishiyama Y, Morisaki T, Sasaki J, Nakao M, Kuwano A, Nakata M, Ushio Y, Saya H. Cloning and characterization of NE-dlg: a novel human homolog of the Drosophila discs large (dlg) tumor suppressor protein interacts with the APC protein. Oncogene 1997; 14:2425-33. [PMID: 9188857 DOI: 10.1038/sj.onc.1201087] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have cloned a cDNA for a novel human homolog of the Drosophila discs large (dig) tumor suppressor protein, termed NE-dlg (neuronal and endocrine dig). Northern blot analysis revealed that the gene is highly expressed in neuronal and endocrine tissues. Fluorescence in situ hybridization (FISH) and radiation hybrid mapping studies localized the NE-dlg gene to chromosome Xq13. We also found that the NE-dlg gene encoded a 100 kDa protein. Immunolocalization studies using an NE-dlg antibody showed that the protein tended to be expressed in non-proliferating cells, such as neurons, cells in Langerhans islets of the pancreas, myocytes of the heart muscles, and the prickle and functional layer cells of the esophageal epithelium. Proliferative cells, including various cultured cancer cell lines and basal cells in the esophageal epithelium, showed little expression of the NE-dlg protein. In addition, yeast two-hybrid screening and in vitro binding assays revealed that the NE-dlg interacted with the carboxyl-terminal region of the APC tumor suppressor protein. These data suggest that NE-dlg negatively regulates cell proliferation through its interaction with the APC protein.
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Ottander U, Nakata M, Bäckström T, Liu K, Ny T, Olofsson JI. Compartmentalization of human chorionic gonadotrophin sensitivity and luteinizing hormone receptor mRNA in different subtypes of the human corpus luteum. Hum Reprod 1997; 12:1037-42. [PMID: 9194662 DOI: 10.1093/humrep/12.5.1037] [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: 02/04/2023] Open
Abstract
The relationship was investigated between different ultrasonographically defined subtypes of the human corpus luteum and progesterone production. Twenty-one women in the mid-luteal phase who underwent laparotomy for benign uterine conditions volunteered for this study. The corpus luteum was identified by preoperative ultrasound and classified into four types according to earlier established criteria, where types a and c were centrally hypoechoic, types b and d were centrally echogenic, types a and b had thin surrounding 'walls' (<3 mm) and types c and d had thick walls (<3 mm). After luteectomy, the theca externa capsule was removed and tissue from directly beneath the surface ('peripheral region') and the layer immediately beneath ('inner region') minced into 4-6 mg pieces. Following preincubation, pieces were incubated for 3 h at 37 degrees C in HEPES-minimal essential medium buffer with or without human chorionic gonadotrophin (HCG; 10 IU/ml), and subsequently progesterone accumulation in the medium was determined by radioimmunoassay. The highest progesterone production was consistently seen in the peripheral region. Type a had a significantly (P > 0.01) lower progesterone production (3.2 +/- 1.5 nmol/g tissue wet weight, mean +/- SEM, n = 4) than that of types b, c and d (17.7 +/- 3.5 nmol/g tissue wet weight, n = 9). All types responded to HCG with an almost two-fold increase in progesterone production. However, the maximal progesterone produced following stimulation by HCG in the type a corpus luteum was <50% of the basal (unstimulated) progesterone synthesis of any other type of corpus luteum. Using in-situ hybridization, with a primate RNA probe complementary to the region coding the extracellular part of the luteinizing hormone (LH) receptor, a highly localized expression of LH receptor mRNA to the peripheral region was found. Negligible or low levels of expression were found in the theca externa capsule and the inner region. No obvious correlations between the different subtypes of corpora lutea and LH receptor mRNA expression were seen. Thus, the ultrasonographic detection of a thin-walled and centrally hypoechoic corpus luteum correlates well with reduced progesterone secretion. The underlying cellular mechanism does not appear to involve a diminished sensitivity to the gonadotrophic stimulation by LH or HCG.
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Moriwaki T, Suganuma N, Furuhashi M, Kikkawa F, Tomoda Y, Boime I, Nakata M, Mizuochi T. Alteration of N-linked oligosaccharide structures of human chorionic gonadotropin beta-subunit by disruption of disulfide bonds. Glycoconj J 1997; 14:225-9. [PMID: 9111139 DOI: 10.1023/a:1018593805890] [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 human chorionic gonadotropin beta-subunit (hCGbeta) is a glycoprotein in which 12 cysteine residues pair to form six intramolecular disulfide bonds. In order to elucidate the effect of each disulfide bond on glycosylation of the molecule, we analysed structures of asparagine-linked oligosaccharides of various recombinant hCGbeta produced in Chinese hamster ovary (CHO) cells: wild-type hCGbeta (betaWT) and mutants in which any one of the six intramolecular disulfide bonds had been disrupted by site-directed mutagenesis. SDS-PAGE analysis of betaWT and these mutants before and after digestion with endoglycosidase F and H revealed structural changes in the oligosaccharide moieties of some mutants. In addition, structural analysis of oligosaccharides obtained from metabolically labeled betaWT and a mutant showed that the mutant contained additional high mannose type oligosaccharides. These results suggest that elimination of a specific disulfide bond, resulting in a change in the protein conformation, disturbs the normal assembly of the mature complex type oligosaccharides in the hCGbeta molecule.
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Uchida T, Usui T, Watanabe T, Higuchi S, Nakata M, Maezawa K, Kikawa Y, Tsunoo M, Nakaya N, Goto Y. Pharmacokinetic properties of YM17E, an inhibitor of acyl coenzyme A: cholesterol acyl transferase, and serum cholesterol levels in healthy volunteers. Eur J Clin Pharmacol 1997; 51:399-406. [PMID: 9049582 DOI: 10.1007/s002280050221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We conducted a single and repeat oral dose study of YM17E, a novel inhibitor of acyl coenzyme A (CoA): cholesterol acyltransferase, in healthy male volunteers to evaluate the pharmacokinetic profile, tolerability and effect of the drug on serum cholesterol. In the single administration study, YM17E was administered after a meal to two groups of subjects (each containing six subjects taking the drug and three taking placebo) receiving 3, 60 and 300 mg or 15, 60 and 450 mg YM17E, respectively. Plasma concentrations of unchanged drug following single oral administration at 3-300 mg after a meal increased with increasing dose. In contrast, plasma concentrations after administration of 450 mg were almost the same as after 300 mg. Unchanged YM17E was not detected in urine after single administration, suggesting that it was excreted via the bile or urine after metabolism. Five active metabolites (M1, M2-a, M2-b, M3 and M4) were observed in plasma at concentrations comparable to those of unchanged YM17E. Their plasma concentrations increased in a slightly greater than dose-dependent manner from 3 to 300 mg. The effect of food was studied in an open crossover design with a 1-week washout period. Twelve subjects received 150 mg YM17E in both the fasted and post-prandial states. The AUC and Cmax after fasting were closely similar to those after a meal, showing that bioavailability was not affected by food intake. In the repeated oral dose study, the subjects received test drug at 150 mg or 300 mg (n = 6 each) or placebo (n = 3) twice a day (after breakfast and after dinner) for 7 days. On days 1 and 7, the subjects received YM17E once a day (after breakfast) for evaluation of pharmacokinetic properties. After repeated oral administration of 150 mg b.d., plasma concentrations reached steady state by day 5 (mean Cmin 48.6 ng.ml-1). After repeated administration of 300 mg b.d., plasma concentrations prior to each daily morning dose increased up to the 5th day (mean Cmin 166.6 ng.ml-1) and then tended to decrease until the 7th day. No significant signs, symptoms or changes in serum cholesterol levels were observed during the single and repeated oral dose studies at 150 mg b.d. Although statistical analysis was not conducted because of the small number of subjects, all subjects receiving repeated oral administration of 300 mg twice daily showed a 25% decrease in serum cholesterol level on day 7, but also the simultaneous occurrence of diarrhoea.
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Yada T, Nakata M, Yaekura K. Pituitary adenylate cyclase-activating polypeptide (PACAP) stimulates insulin secretion in islets and potentiates glucose-transport in adipocytes. THE JAPANESE JOURNAL OF PHYSIOLOGY 1997; 47 Suppl 1:S27. [PMID: 9266319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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270
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Kurita A, Takashima S, Nakata M, Kubo Y, Saiki T, Ohsumi S, Yokoyama N, Tanada M, Takiyama W, Saeki H. [Granisetron versus granisetron plus methylprednisolone in the prevention of chemotherapy induced nausea and vomiting--in adjuvant chemotherapy, including CDDP against gastric cancer]. Gan To Kagaku Ryoho 1997; 24:49-54. [PMID: 9020945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
CDDP is one of the most effective drugs in chemotherapy for gastric cancer. We compared the antiemetic effect of a combination of granisetron and methylprednisolone with that of granisetron administered alone. Twenty postgastrectomy-patients who were to receive moderately emetogenic chemotherapy, including CDDP, were enrolled in randomized fashion to evaluate the efficacy and toxicity of two antiemetic regimens. The following antiemetic regimens were used: 3 mg of granisetron given intravenously before chemotherapy (11 patients) or a combination of granisetron and 250 mg of methylprednisolone in the same manner (9 patients). Granisetron combined with methylprednisolone tender to be more effective than granisetron alone. The adverse effects were very mild. Their efficacy against delayed emesis is still not entirely satisfactory.
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271
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Yada T, Sakurada M, Nakata M, Ihida K, Yaekura K, Shioda S, Kikuchi M. Current status of PACAP as a regulator of insulin secretion in pancreatic islets. Ann N Y Acad Sci 1996; 805:329-40; discussion 341-2. [PMID: 8993414 DOI: 10.1111/j.1749-6632.1996.tb17494.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PACAP-27 and PACAP-38 as low as 10(-13) M stimulate insulin release from rat islets in a glucose-dependent manner. PACAP also glucose dependently increases cAMP and [Ca2+]i in rat islet beta cells. The [Ca2+]i and insulin secretory responses to PACAP exhibit a similar concentration-response relationship, exhibiting a peak at 10(-13) M. When the [Ca2+]i response is abolished by nitrendipine, a blocker of L-type Ca2+ channels, the insulin response is also inhibited. Insulinotropic peptides glucagon, GLP-1, and VIP also increase [Ca2+]i in beta cells, but only in the nanomolar concentration range. PACAP is 4 logs more potent that VIP, a peptide that exhibits 68% amino acid homology and shares the type II PACAP receptor with PACAP. Immunoreactivity for the type I PACAP receptor is demonstrated in rat islets. Furthermore, PACAP immunoreactivity is demonstrated in nerve fibers and islets in rat pancreas. Based on these findings, we can draw the following conclusions: (1) PACAP is localized in pancreatic nerve fibers and islets; (2) PACAP in the subpicomolar range stimulates insulin release from islets; (3) the stimulation of insulin release is mediated by the cAMP-dependent increase in [Ca2+]i in beta cells; (4) all the PACAP effects are glucose-dependent; (5) PACAP is the most potent insulinotropic hormone known, and (6) the type I PACAP receptor appears to mediate the action of PACAP in the subpicomolar range. Finally, we hypothesize that PACAP is a pancreatic peptide of both neural and islet origin and functions as an intrinsic potentiator of glucose-induced insulin secretion in pancreatic islets (FIG 6).
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272
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Koga Y, Toshima H, Kimura A, Harada H, Koyanagi T, Nishi H, Nakata M, Imaizumi T. Clinical manifestations of hypertrophic cardiomyopathy with mutations in the cardiac beta-myosin heavy chain gene or cardiac troponin T gene. J Card Fail 1996; 2:S97-103. [PMID: 8951566 DOI: 10.1016/s1071-9164(96)80064-9] [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: 02/03/2023]
Abstract
Introduction of molecular genetics has improved our understanding of HCM substantially, but has simultaneously raised further important questions. Studies on HCM are revealing a more complex picture than might have been expected on clinical grounds. Further extensive studies are warranted to elucidate the pathogenesis and pathophysiology of HCM, and to establish therapeutic strategies to cure or prevent the development of the disease.
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273
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Katsumata N, Matsuno Y, Nakayama H, Takenaka T, Kobayashi Y, Takeyama K, Narabayashi M, Fukushima T, Yokozawa T, Nakata M, Tajima K, Ikeda H, Tobinai K. Prognostic factors and a predictive model of follicular lymphoma: a 25-year study at a single institution in Japan. Jpn J Clin Oncol 1996; 26:445-54. [PMID: 9001350 DOI: 10.1093/oxfordjournals.jjco.a023262] [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: 02/03/2023] Open
Abstract
The incidence of follicular lymphoma in Japan is far lower than that in western countries, and no large-scale clinicopathologic studies on this neoplasm have been conducted in Japan. We reviewed histopathological specimens from 118 of 135 patients who had been diagnosed as having follicular lymphoma between 1968 and 1993. Prognostic factors influencing survival were analyzed using univariate and multivariate analyses. Factors that were independently significant upon multivariate analysis were incorporated into a predictive model. Ninety-three patients (78.8%) had a confirmed diagnosis of follicular lymphoma. Twenty-one of the remaining 25 patients were categorized as having other lymphoma subtypes, and four patients showed indefinite findings or those suggesting diseases other than lymphoma. Major characteristics of the 93 patients with follicular lymphoma were a median age of 53 years (20-85); 59 males (63%) and 34 females (37%); small cleaved cell type in 33 (35%), mixed cell type in 41 (44%) and large cell type in 19 (20%); stage I/II in 41 (44%) and stage III/IV in 50 (54%). Overall survival was 71% at 5 years, 58% at 10 years, and 43% at 15 years with a median survival of 13.3 years. Multivariate analysis revealed that two variables, age (>60) (P=0.001) and the serum LDH level (>1 x normal value) (P=0.026), were unfavorably significant prognostic factors influencing survival. The predictive model using these two variables identified three risk groups with estimated five-year survival rates of 88.5%, 56.8%, and 31.5%. Age and serum LDH were significant predictors of survival in Japanese patients with follicular lymphoma. Our predictive model may provide a basis for future therapeutic trials against follicular lymphoma in Japan.
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274
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Yamazaki J, Igarashi M, Nakata M, Okamoto K, Hosoi H, Morishita T, Nakano H, Yabe Y, Yoshiwara K, Koyama N. Estimating myocardial damage and the need for surgery in patients with valvular heart disease by Tl-201 SPECT. Clin Nucl Med 1996; 21:855-63. [PMID: 8922847 DOI: 10.1097/00003072-199611000-00007] [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
Left ventricular myocardial disorders due to volume overload were investigated by Tl-201 myocardial SPECT (Tl-201 SPECT) in patients with aortic or mitral regurgitation, and its utility for timing cardiac valve replacement was studied. There were significant correlations between Tl-201 scores and electrocardiographic changes and the New York Heart Association classification. There also were favorable correlations between Tl-201 scores and the left ventricular end-diastolic dimension and between Tl-201 scores and left ventricular ejection fraction, and a close relationship between the presence of a left ventricular myocardial disorder and left ventricular diameter. These results suggest that myocardial perfusion abnormalities and left ventricular myocardial disorders may accompany left ventricular dilatation owing to volume overload. After valve replacement, left ventricular end-diastolic dimension normalized, and Tl-201 scores improved slightly, suggesting normalization of myocardial perfusion. When moderate or more severe Tl-201 defects are present on Tl-201 SPECT images, in addition to inverted Tl-201 waves on the electrocardiogram or a left ventricular end-diastolic dimension of 65 mm or more, cardiac valve replacement should be considered.
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275
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Nakata M, Ohkawa H. [Enzyme immunoassay with monoclonal antibody for environmental contaminants]. TANPAKUSHITSU KAKUSAN KOSO. PROTEIN, NUCLEIC ACID, ENZYME 1996; 41:2132-8. [PMID: 8937222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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