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Hayashi T, Yamada K, Esaki T, Kuzuya M, Satake S, Ishikawa T, Hidaka H, Iguchi A. Estrogen increases endothelial nitric oxide by a receptor-mediated system. Biochem Biophys Res Commun 1995; 214:847-55. [PMID: 7575554 DOI: 10.1006/bbrc.1995.2364] [Citation(s) in RCA: 284] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To determine the mechanism of the antiatherosclerotic effect of estrogen, we investigated the effect of estrogen on endothelial nitric oxide synthase (NOS-3). Preincubation with a physiologic concentration of 17 beta-estradiol (10(-12)-10(-8) M) over 8 hours significantly enhanced the activity of NOS-3 in endothelial cells of cultured human umblical vein (HUVEC) and of bovine aortas (BAEC). 17 beta-estradiol also enhanced the release of nitric oxide (NO) as measured by an NO selective meter and NO2-/NO3-, metabolites of NO, from endothelial cells. Western blot showed a similar effect of 17 beta-estradiol on NOS-3. The estrogen receptor antagonists, tamoxifen and ICI182780, each inhibited the effect of 17 beta-estradiol by 80%. The effect of 17 beta-estradiol gradually decreased in cells beyond the 10th passage and was not significant in cells beyond the 16th passage. Immunocytochemistry showed the existence of estrogen receptor in HUVEC and BAEC (less than 5 passages) and the sparseness of the existence in BAEC beyond the 16th passage. Estrogen increases NOS-3 via a receptor-mediated system, and estrogen receptor, which appeared to be altered by cell senescence, could be important in the release of NO from endothelium.
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Uno I, Wang Z, Chiba M, Chun YS, Gong SL, Hara Y, Jung E, Lee SS, Liu M, Mikami M, Music S, Nickovic S, Satake S, Shao Y, Song Z, Sugimoto N, Tanaka T, Westphal DL. Dust model intercomparison (DMIP) study over Asia: Overview. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006575] [Citation(s) in RCA: 174] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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174 |
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Satake S, Masumura M, Ishizaki H, Nagata K, Kataoka H, Suzuki A, Mizoguchi A. Bombyxin, an insulin-related peptide of insects, reduces the major storage carbohydrates in the silkworm Bombyx mori. Comp Biochem Physiol B Biochem Mol Biol 1997; 118:349-57. [PMID: 9440228 DOI: 10.1016/s0305-0491(97)00166-1] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effects of an insect insulin-related peptide, bombyxin, on carbohydrate metabolism were investigated in the silkworm Bombyx mori. Bombyxin lowered the concentration of the major hemolymph sugar, trehalose, in a dose-dependent manner when injected into neck-ligated larvae. Bombyxin also caused elevated trehalase activity in the midgut and muscle, suggesting that bombyxin induces hypotrehalosemia by promoting the hydrolysis of hemolymph trehalose to glucose and thereby facilitating its transport into tissues. In addition, bombyxin reduced the glycogen content in the fat body and concurrently raised the percentage of active glycogen phosphorylase in this tissue. Because hemolymph trehalose is also a major storage form of carbohydrate in insects, our results indicate that bombyxin reduces the amount of both principal storage carbohydrates in B. mori larvae. It is therefore suggested that although bombyxin is involved in the control of carbohydrate metabolism like insulin, the physiological role of bombyxin in insects is different from that of insulin in mammals.
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Okada M, Yamagishi H, Satake S, Matsuoka H, Miyamoto Y, Yoshimura M, Tsubota N. Survival related to lymph node involvement in lung cancer after sleeve lobectomy compared with pneumonectomy. J Thorac Cardiovasc Surg 2000; 119:814-9. [PMID: 10733774 DOI: 10.1016/s0022-5223(00)70018-3] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
OBJECTIVE The purpose of this study was to compare the outcomes after sleeve lobectomy and pneumonectomy for patients with non-small cell lung cancer distributed according to their nodal involvement status. METHODS Of 1172 patients in whom primary non-small cell lung carcinoma, including mediastinal lymph nodes, was completely excised, 151 patients underwent sleeve lobectomy and 60 underwent pneumonectomy. For bias reduction in comparison with a nonrandomized control group, we paired 60 patients undergoing sleeve lobectomy with 60 patients undergoing pneumonectomy by using the nearest available matching method. RESULTS The 30-day postoperative mortality was 2% (1/60) in the pneumonectomy group and 0% in the sleeve lobectomy group. Postoperative complications occurred in 13% of patients in the sleeve lobectomy group and in 22% of those in the pneumonectomy group. Local recurrences occurred in 8% of patients in the sleeve lobectomy group and in 10% of those in the pneumonectomy group. The overall 5- and 10-year survivals for the sleeve lobectomy group were 48% and 36%, respectively, whereas those for the pneumonectomy group were 28% and 19%, respectively (P =.005). Multivariable analysis showed that the operative procedure, T factor, and N factor were significant independent prognostic factors and revealed that survival after sleeve lobectomy was significantly longer than that after pneumonectomy (P =.03). CONCLUSIONS These data suggest that sleeve lobectomy should be performed instead of pneumonectomy in patients with non-small cell lung cancer regardless of their nodal status whenever complete resection can be achieved because this is a lung-saving procedure with lower postoperative risks and is as curative as pneumonectomy.
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Usami Y, Satake S, Nakayama F, Matsumoto M, Ohnuma K, Komori T, Semba S, Ito A, Yokozaki H. Snail-associated epithelial–mesenchymal transition promotes oesophageal squamous cell carcinoma motility and progression. J Pathol 2008; 215:330-9. [PMID: 18491351 DOI: 10.1002/path.2365] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Satake S, Clark N, Rimland D, Nolte FS, Tenover FC. Detection of vancomycin-resistant enterococci in fecal samples by PCR. J Clin Microbiol 1997; 35:2325-30. [PMID: 9276411 PMCID: PMC229963 DOI: 10.1128/jcm.35.9.2325-2330.1997] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Surveillance cultures for vancomycin-resistant enterococci (VRE) are time-consuming and expensive for the laboratory to perform. Therefore, we investigated the use of PCR as an alternative method of detecting and identifying VRE directly in fecal samples. PCR primers directed to vanA, vanB, vanC1, vanC2, and enterococcal ligase genes were used to detect and identify VRE in fecal material obtained by rectal or perirectal swabbing. Although PCR-inhibitory substances were present in DNA prepared directly from the swabs, the inhibitory substances could be reduced by processing the nucleic acid with two commercially available DNA preparation columns. Fecal material from 333 swabs was cultured on several selective agar media before and after broth enrichment. DNA was extracted from the fecal material and was analyzed by PCR. By using all four primer sets, only 59 (67.8%) of the samples were positive for vanA. However, after retesting the negative samples with only the vanA primer set, 77 (88.5%) of 87 specimens that were culture positive for Enterococcus faecium containing vanA were positive by PCR. One specimen was PCR positive for the vanA gene but culture negative for enterococci. The specificity of the vanA assay was 99.6%. PCR analysis of enrichment broth samples with all four primers sets after 15 to 18 h of incubation detected 74 (85.1%) of the 87 culture-positive specimens. The specificity of the vanA assay after the enrichment step was 100%. No vanB-containing enterococci were recovered by culture. Since 16 samples can be tested by PCR in 4 h (including electrophoresis), identification of VRE is possible within 8 h of specimen submission at a cost of approximately $10.12/assay. Thus, PCR may be a cost-effective alternative to culture for surveillance of VRE in some hospitals.
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Ramos MA, Kuzuya M, Esaki T, Miura S, Satake S, Asai T, Kanda S, Hayashi T, Iguchi A. Induction of macrophage VEGF in response to oxidized LDL and VEGF accumulation in human atherosclerotic lesions. Arterioscler Thromb Vasc Biol 1998; 18:1188-96. [PMID: 9672081 DOI: 10.1161/01.atv.18.7.1188] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The interaction between macrophages and oxidatively modified low density lipoprotein (Ox-LDL) appears to play a central role in the development of atherosclerosis, not only through foam cell formation but also via the induction of numerous cytokines and growth factors. The current study demonstrated that Ox-LDL upregulated vascular endothelial growth factor (VEGF) mRNA expression in RAW 264 cells, a monocytic cell line, in a time- and concentration-dependent manner and that Ox-LDL stimulated VEGF protein secretion from the cells. Lysophosphatidylcholine, a component of Ox-LDL, also enhanced VEGF mRNA expression in RAW 264 cells and VEGF secretion from RAW 264 cells, with a maximal effect at a concentration of 10 micromol/L lysophosphatidylcholine. Immunohistochemical studies showed that human early atherosclerotic lesions exhibited intense VEGF immunoreactivity in subendothelial macrophage-rich regions of the thickened intima. In atherosclerotic plaques, VEGF staining was also observed in foam cell-rich regions adjacent to the lipid core or the neovascularized basal regions of plaque consisting predominantly of smooth muscle cells. High-power-field observation revealed that VEGF was localized in the extracellular space as well as at the macrophage cell surface. These observations suggest the possible involvement of Ox-LDL in the development of human atherosclerosis through VEGF induction in macrophages.
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Masumura M, Satake S, Saegusa H, Mizoguchi A. Glucose stimulates the release of bombyxin, an insulin-related peptide of the silkworm Bombyx mori. Gen Comp Endocrinol 2000; 118:393-9. [PMID: 10843790 DOI: 10.1006/gcen.1999.7438] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effects of starvation and feeding on the release of bombyxin, a peptide of insulin superfamily in insects, from the larval brain of the silkworm Bombyx mori were investigated. Following starvation, the bombyxin titer in the hemolymph of larvae decreased, whereas its content in the brain increased. On the other hand, refeeding of the starved larvae resulted in an increase in the hemolymph bombyxin titer and a rapid decrease in the hormone level in the brain. These results indicate that the release of bombyxin from the brain is suppressed by starvation and stimulated by feeding. The hemolymph glucose titer also changed sharply upon starvation and refeeding, and a close relationship was observed between the changes in glucose concentrations and bombyxin titers in the hemolymph. The injection of glucose into starved larvae could mimic the effect of refeeding on the release of bombyxin, suggesting that glucose serves as the signal for the "fed" state of the animal. It is likely that glucose is a common nutritional signal for inducing the release of mammalian and insect insulins.
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Satake S, Saitow F, Yamada J, Konishi S. Synaptic activation of AMPA receptors inhibits GABA release from cerebellar interneurons. Nat Neurosci 2000; 3:551-8. [PMID: 10816310 DOI: 10.1038/75718] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A single neurotransmitter elicits diverse physiological responses through activation of multiple receptor subtypes and/or heterosynaptic interactions involving distinct synaptic targets. We found that a typical excitatory transmitter released from the climbing fiber (CF) in the cerebellar cortex not only excited Purkinje cells directly but also presynaptically inhibited GABAergic transmission from interneurons converging on the same Purkinje cells. Both homosynaptic and heterosynaptic actions of the CF transmitter (possibly glutamate) were mediated by activation of AMPA receptors. Dual AMPA receptor-mediated functions of excitation and disinhibition may ensure transmission of cerebellar CF signals controlling sensorimotor coordination.
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Satake S, Kaya M, Sakurai S. Hemolymph ecdysteroid titer and ecdysteroid-dependent developmental events in the last-larval stadium of the silkworm, Bombyx mori: role of low ecdysteroid titer in larval-pupal metamorphosis and a reappraisal of the head critical period. JOURNAL OF INSECT PHYSIOLOGY 1998; 44:867-881. [PMID: 12770423 DOI: 10.1016/s0022-1910(98)00075-4] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The endocrine regulation of larval-pupal metamorphosis was studied in the silkworm, Bombyx mori, by measuring the following changes: hemolymph ecdysteroid titer, the secretory activity of prothoracic glands and the responsiveness of larvae to ecdysteroids and prothoracicotropic hormone (PTTH), with regard to developmental events such as the occurrence of spinneret pigmentation, initiation of cocoon spinning and onset of wandering stage as indicated by gut purge. These measurements were concentrated especially on the time before and after the head critical period (HCP) which falls 3-4 days before the gut purge ([Sakurai, 1984]). A small increase in the hemolymph ecdysteroid titer was first found during the HCP, and then the titer increased with daily fluctuations. Small but significant titer peaks were found prior to the occurrence of both spinneret pigmentation and gut purge, indicating that an individual titer peak could possess a specific role in development. Responsiveness of larvae to exogenous 20-hydroxyecdysone (20E) after the HCP was markedly higher than that before the HCP. The sensitivity of the prothoracic gland to PTTH also changed during the HCP. The results thus showed that the HCP is not the period after which an additional PTTH release is not required for the developmental events occurring on schedule, but rather it is the period during which complex events occur not only in the endocrine glands but also in the peripheral tissues. In addition, various developmental phenomena before gut purge are brought about by the hemolymph ecdysteroid whose concentration gradually increased with daily fluctuations, and these precise changes in the titer appeared to be important for the sequential occurrence of developmental events in the larval-pupal metamorphosis.
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Okada M, Tsubota N, Yoshimura M, Miyamoto Y, Matsuoka H, Satake S, Yamagishi H. Extended sleeve lobectomy for lung cancer: the avoidance of pneumonectomy. J Thorac Cardiovasc Surg 1999; 118:710-3; discussion 713-4. [PMID: 10504638 DOI: 10.1016/s0022-5223(99)70017-6] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE We have tried atypical bronchoplasties in patients with noncompromised lung function with centrally located cancers to avoid pneumonectomy. We evaluated the efficacy of extended sleeve lobectomy in such patients. METHODS Among 157 patients undergoing bronchoplasty for primary non-small cell lung carcinoma, 15 patients underwent extended sleeve lobectomy. RESULTS According to the mode of reconstruction, the 15 patients were classified into 3 groups: (A) anastomosis between the right main and lower bronchi with resection of the upper and middle lobes (n = 6), (B) anastomosis between the left main and basal segmental bronchi with resection of the upper lobe and superior segment of the lower lobe (n = 4), and (C) anastomosis between the left main and upper division bronchi with resection of the lingular segment and lower lobe (n = 5). The tumors were completely resected in all patients. Pulmonary angioplasty was carried out in 8 patients. Bronchial reconstruction was successful in all patients. Pulmonary vein thrombosis resulting from overstretching of the inferior pulmonary vein occurred in 1 patient of group A and was relieved by completion pneumonectomy. There was neither operative mortality nor local recurrence. Although all patients with stage IIB disease and half of patients with stage IIIA disease were alive without recurrence (12-106 months), half of the patients with stage IIIA disease died of distant metastases within 1 year. CONCLUSIONS We suggest that this extended sleeve lobectomy, which is technically demanding, should be considered in patients with centrally located lung cancer, because this lung-saving operation is safer than pneumonectomy and is equally curative.
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Kuzuya M, Satake S, Esaki T, Yamada K, Hayashi T, Naito M, Asai K, Iguchi A. Induction of angiogenesis by smooth muscle cell-derived factor: possible role in neovascularization in atherosclerotic plaque. J Cell Physiol 1995; 164:658-67. [PMID: 7544360 DOI: 10.1002/jcp.1041640324] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The development of atherosclerotic plaque is associated with neovascularization in the thickened intima and media of vascular walls. Neovascularization may have a role in the progression of atherosclerotic plaque as well as in the development of intraplaque hemorrhage. However, the mechanism and stimulus for neovascularization in atherosclerotic plaque are unknown. We postulated that smooth muscle cells (SMCs), a major cellular component in the vascular wall, might contribute to the induction of neovascularization in atherosclerotic plaque through the secretion of an angiogenic factor. We observed that endothelial cells (ECs) cultured on collagen gel with SMC-conditioned medium became spindle shaped, invaded the underlying collagen gel, and organized a capillary-like branching cord structure in the collagen gel. The conditioned medium also stimulated EC proliferation and increased the EC-associated plasminogen activator activity. The angiogenic factor in SMC-conditioned medium was retained in a heparin-Sepharose column and eluted with 0.9 M NaCl. Neutralizing anti-vascular endothelial growth factor (VEGF) antibody attenuated the angiogenic activity in the conditioned medium, including the induction of morphologic changes in ECs, mitogenic activity, and increased plasminogen activator activity associated with ECs. Immunoblotting analysis confirmed the secretion of VEGF from SMCs. These observations indicate that SMC may be responsible for the neovascularization in atherosclerotic plaque through the secretion of VEGF.
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Yamada J, Saitow F, Satake S, Kiyohara T, Konishi S. GABA(B) receptor-mediated presynaptic inhibition of glutamatergic and GABAergic transmission in the basolateral amygdala. Neuropharmacology 1999; 38:1743-53. [PMID: 10587090 DOI: 10.1016/s0028-3908(99)00126-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The information processing at central synapses is mediated not only by homosynaptic transmission with direct synaptic connections but also by heterosynaptic interactions between distinct synaptic inputs. Using rat brain slices and whole-cell recordings this study aimed to examine the roles of GABA(B) receptors in synaptic interactions in the basolateral amygdala (BLA), a critical brain structure related to fear and anxiety. Stimulation in the BLA produced non-NMDA type glutamate receptor antagonist-sensitive excitatory postsynaptic currents (EPSCs) and bicuculline-sensitive inhibitory postsynaptic currents (IPSCs) in the BLA neurons. The GABA(B) receptor agonist baclofen markedly inhibited both EPSCs and IPSCs in a concentration-dependent manner, and the baclofen-induced inhibition was selectively abolished by the GABA(B) receptor antagonist CGP55845A. The paired-pulse ratio of EPSC and IPSC amplitude was increased by baclofen. The effect of baclofen was mimicked by lowering the external Ca2+ concentration but not by glutamate- and GABA(A)-receptor antagonists. The frequency but not the mean amplitude of miniature EPSCs and IPSCs was decreased by baclofen. The findings suggest that activation of GABA(B) receptors by baclofen reduces the strength of excitatory and inhibitory transmission in the BLA by a presynaptic mechanism. Repetitive conditioning stimulation applied to GABAergic synaptic inputs exerted an inhibitory action on glutamatergic excitatory transmission, and the stimulation-induced inhibition was abolished by CGP55845A. Furthermore, the paired-pulse ratio of EPSCs was increased during the stimulation-induced inhibition. The results in this study provide evidence that synaptic activation of GABA(B) heteroreceptors elicits presynaptic inhibition of glutamatergic excitatory transmission in the BLA.
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Saitow F, Satake S, Yamada J, Konishi S. beta-adrenergic receptor-mediated presynaptic facilitation of inhibitory GABAergic transmission at cerebellar interneuron-Purkinje cell synapses. J Neurophysiol 2000; 84:2016-25. [PMID: 11024094 DOI: 10.1152/jn.2000.84.4.2016] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Norepinephrine (NE) has been shown to elicit long-term facilitation of GABAergic transmission to rat cerebellar Purkinje cells (PCs) through beta-adrenergic receptor activation. To further examine the locus and adrenoceptor subtypes involved in the NE-induced facilitation of GABAergic transmission, we recorded inhibitory postsynaptic currents (IPSCs) evoked by focal stimulation with paired-pulse (PP) stimuli from PCs in rat cerebellar slices by whole cell recordings and analyzed the PP ratio of the IPSC amplitude. NE increased the IPSC amplitude with a decease in the variance of the PP ratio, which was mimicked by presynaptic manipulation of the transmission caused by increasing the extracellular Ca(2+) concentration, confirming that the presynaptic adrenergic receptors are responsible for the facilitation. Pharmacological tests showed that the beta(2)-adrenoceptor antagonist, ICI118,551, but not the beta(1)-adrenoceptor antagonist, CGP20712A, blocked the NE-induced IPSC facilitation, suggesting that the beta(2)-adrenoceptors on cerebellar interneurons, basket cells (BCs), mediate the noradrenergic facilitation of GABAergic transmission. Double recordings were performed from BCs and PCs to further characterize the regulation of the GABAergic synapses. First, on-cell recordings from BCs showed that the beta-agonist isoproterenol (ISP) increased the frequencies of the spontaneous spikes in BCs and the spike-triggered IPSCs in PCs recorded with the whole cell mode. The amplitude of the spike-triggered IPSCs decreased or increased depending on the individual GABAergic synapses examined. Forskolin invariably increased both the amplitude and the frequency of the spike-triggered IPSCs. Double whole cell recordings from BC-PC pairs showed that ISP mainly caused an increase in the amplitude of the IPSCs evoked in the PCs by an action current in the BCs produced in response to voltage steps from -60 to -10 mV. Our data suggest that the noradrenergic facilitation of GABAergic transmission in the rat cerebellar cortex is mediated, at least in part, by depolarization and action potential discharges in the BCs through activation of the beta(2)-adrenoceptors in BCs coupled to intracellular cyclic AMP formation.
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Kuzuya M, Satake S, Ai S, Asai T, Kanda S, Ramos MA, Miura H, Ueda M, Iguchi A. Inhibition of angiogenesis on glycated collagen lattices. Diabetologia 1998; 41:491-9. [PMID: 9628264 DOI: 10.1007/s001250050937] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Advanced glycation endproduct (AGE) accumulation in extracellular matrix proteins has been demonstrated in diabetic patients with a significant correlation with the severity of diabetic complications. AGE accumulation induces matrix protein cross-link formation, resulting in an increased stiffness of matrix fibres and the reduction of the susceptibility of matrix proteins to proteolytic degradation. We examined whether glycation-induced collagen cross-linking may affect vascular endothelial cell behaviours such as invasion, proliferation and differentiation, using the in vitro angiogenesis model of capillary-like structure formation in three-dimensional matrices of collagen type I. Endothelial cells cultured on collagen gel with angiogenic factors (the combination of fibroblast growth factor-2 and vascular endothelial growth factor) invaded the underlying collagen matrix, and organized capillary-like cord structures in the gel. We found that endothelial cell invasion into glycated collagen gel was significantly attenuated without any effect on proteinase activity including cell-associated plasminogen activator and matrix metalloproteinase in the conditioned medium. In addition, subsequent capillary-like cord formation was also inhibited in glycated collagen gel. In contrast, endothelial cell proliferation was enhanced on glycated collagen gel with or without angiogenic factors compared with control collagen gel. These results suggest that the structural alterations of extracellular matrix proteins through the glycation-induced cross-link formation affect the interaction between endothelial cell and extracellular matrix, resulting in the impairment of an adequate neovascularization in diabetic patients.
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Satake S, Kuzuya M, Miura H, Asai T, Ramos MA, Muraguchi M, Ohmoto Y, Iguchi A. Up-regulation of vascular endothelial growth factor in response to glucose deprivation. Biol Cell 1998; 90:161-8. [PMID: 9691433 DOI: 10.1016/s0248-4900(98)80337-7] [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: 11/16/2022]
Abstract
Vascular endothelial growth factor (VEGF), also known as a vascular permeability factor (VPF), is an endothelial specific mitogen and is a potent inducer of angiogenesis. Recently it has been reported that hypoxia induces VEGF mRNA expression in various cells. Since both oxygen and glucose are required for efficient production of energy, we examined the effect of glucose deprivation on VEGF mRNA expression and VEGF protein production in U-937 (a human monocytic cell line) cells. Both the mRNA expression and secretion of VEGF increased after exposure to low glucose. Addition of L-glucose, the L-stereoisomer of D-glucose, did not prevent the up-regulation of VEGF expression. The conditioned medium from glucose-deprived cells, followed by supplementation with glucose, did not up-regulate VEGF mRNA expression in U-937 cells. The low glucose-induced VEGF mRNA expression returned to the control level after supplementation with D-glucose. Furthermore, oligomycin, a mitochondrial ATP synthase inhibitor, increased VEGF protein production. The results suggest that the up-regulation of VEGF mRNA in U-937 cells in response to glucose deprivation is not mediated by autocrine factors from the cells nor is the osmotic change of the medium mediated by the deficiency of glucose metabolism in the cells. Our results also suggest that the intracellular ATP depletion due to glucose deprivation may be one of the causes for increased VEGF mRNA expression. We speculate that local hypoglycemia may act as an essential trigger for angiogenesis through the VEGF gene expression.
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Okishige K, Yamashita K, Yoshinaga H, Azegami K, Satoh T, Goseki Y, Fujii S, Ohira H, Satake S. Electrophysiologic effects of ischemic preconditioning on QT dispersion during coronary angioplasty. J Am Coll Cardiol 1996; 28:70-3. [PMID: 8752796 DOI: 10.1016/0735-1097(96)00119-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVES The aim of this study was to examine the effect of ischemic preconditioning on the manner of ventricular repolarization by assessing the change in QT dispersion during coronary angioplasty. BACKGROUND QT interval dispersion reflects regional variations in ventricular repolarization and cardiac electrical instability. Previous studies have suggested that increased QT dispersion is associated with an increased incidence of malignant ventricular arrhythmias, whereas brief episodes of myocardial ischemia can render the heart more resistant to subsequent ischemic episodes, a phenomenon called ischemic preconditioning. METHODS To assess the effects of ischemic preconditioning on myocardial repolarization by examining the change in QT dispersion during coronary angioplasty, we studied 47 consecutive patients (39 men and 8 women; mean age 57 +/- 16 years). QT dispersion was measured after each balloon inflation during coronary angioplasty. Statistical analysis was performed by using repeated measurement of analysis of variance. RESULTS There were significant differences in QT dispersion as the number of balloon inflations increased (mean +/- SD 52 +/- 14, 42 +/- 11, 36 +/- 9, 31 +/- 10 and 29 +/- 11 ms, respectively [p < 0.01], for the first, second, third, fourth and fifth balloon inflations). The magnitude of decrease in QT dispersion was significant in the first and second balloon inflations, then became insignificant with later inflations. CONCLUSIONS These data indicate that the gradual decrease in QT dispersion provoked by coronary artery occlusion and reperfusion during coronary angioplasty may be associated with electrophysiologic effects of ischemic preconditioning on myocardium in the human heart.
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Kuzuya M, Satake S, Ramos MA, Kanda S, Koike T, Yoshino K, Ikeda S, Iguchi A. Induction of apoptotic cell death in vascular endothelial cells cultured in three-dimensional collagen lattice. Exp Cell Res 1999; 248:498-508. [PMID: 10222141 DOI: 10.1006/excr.1999.4422] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Endothelial cells derived from fetal bovine aorta (BAECs) undergo apoptosis in three-dimensional (3-D) type I collagen lattice in the absence of specific angiogenic factor. In the presence of angiogenic factor, BAECs survive and form a capillary-like tube structure in 3-D culture. In the present study we elucidate the mechanisms of BAECs apoptosis or survival and tube formation in 3-D culture. When BAECs embedded in collagen lattice were cultured with angiogenic factor (fibroblast growth factor-2 (FGF-2) or 4beta-phorbol 12-myristate 13-acetate (PMA)) in the presence of PD98059, a specific inhibitor of mitogen-activated protein kinase kinase, BAECs did not form tube structures and underwent apoptosis in collagen lattice. Function-blocking antibody against alphavbeta3 integrin also inhibited tube formation and induced apoptosis in 3-D culture in the presence of angiogenic factors. Exposure of BAECs to FGF-2 and PMA had no effect on the alphavbeta3 integrin expression but induced the activation of alphavbeta3 integrin. PD98059 attenuated alphavbeta3 integrin activation in response to angiogenic factor. KB-R8301, a hydroxamic acid-based matrix metalloproteinase (MMP) inhibitor, prevented apoptotic cell death in the absence of angiogenic factor in 3-D culture and enhanced capillary-like tube formation in the presence of angiogenic factor, which was not inhibited by the anti-alphavbeta3 integrin antibody. The results suggest that angiogenic factor-induced alphavbeta3 integrin activation through the MEK-ERK pathway regulates the BAEC fate between apoptosis and angiogenesis in collagen lattice. MMP derived from BAECs seems to play a key role in the release of cryptic ligands for alphavbeta3 integrin from intact collagen.
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Tokars JI, Satake S, Rimland D, Carson L, Miller ER, Killum E, Sinkowitz-Cochran RL, Arduino MJ, Tenover FC, Marston B, Jarvis WR. The prevalence of colonization with vancomycin-resistant Enterococcus at a Veterans' Affairs institution. Infect Control Hosp Epidemiol 1999; 20:171-5. [PMID: 10100542 DOI: 10.1086/501606] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To study vancomycin-resistant Enterococcus (VRE) prevalence, risk factors, and clustering among hospital inpatients. DESIGN Rectal-swab prevalence culture survey conducted from February 5 to March 22, 1996. SETTING The Veterans' Affairs Medical Center, Atlanta, Georgia. PATIENTS Hospital (medical and surgical) inpatients. RESULTS The overall VRE prevalence was 29% (42/147 patients). The VRE prevalence was 52% (38/73 patients) among patients who had received at least one of six specific antimicrobials during the preceding 120 days, compared with only 5% (4/74) among those who had not received the antimicrobials (relative risk, 9.6; P<.001). The longer the period (up to 120 days) during which antimicrobial use was studied, the more closely VRE status was predicted. Among 67 hospital patients in 28 multibed rooms, clustering of VRE among current roommates was not found. CONCLUSIONS At this hospital with relatively high VRE prevalence, VRE colonization was related to antibiotic use but not to roommate VRE status. In hospitals with a similar VRE epidemiology, obtaining cultures from roommates of VRE-positive patients may not be as efficient a strategy for identifying VRE-colonized patients as obtaining screening cultures from patients who have received antimicrobials.
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Satake S, Yoshihara E, Nakae T. Diffusion of beta-lactam antibiotics through liposome membranes reconstituted from purified porins of the outer membrane of Pseudomonas aeruginosa. Antimicrob Agents Chemother 1990; 34:685-90. [PMID: 2163239 PMCID: PMC171674 DOI: 10.1128/aac.34.5.685] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Determination of the rates of diffusion of beta-lactam antibiotics through purified Pseudomonas aeruginosa porins C, D2, and E in liposomes yielded the following results. (i) The rates of carbapenem (imipenem and meropenem) diffusion through the protein D2 pore were roughly 2 to 70 times higher than those through other porin pores. It is not clear why the protein D2 pore allowed rapid diffusion of carbapenems. The rates of diffusion of glucosamine and triglycine through the protein D2 pore were about 14 and 4 times higher, respectively, than that of an uncharged test solute with a similar Mr, glucose. (ii) The rates of diffusion of antipseudomonal anionic beta-lactams such as piperacillin, ceftazidime, cefsulodin, and aztreonam through the protein C pore were higher than those through other porin pores. This was probably due to the slightly larger pore size and the slight anion selectivity of protein C, since the apparent exclusion limit of the protein C pore for uncharged saccharides is higher than that of other porins and the rate of diffusion of gluconic acid through the protein C pore is about double that for glucose. (iii) The rates of diffusion of cefoperazone through all three species of porin were relatively high. These results indicate that the antipseudomonal beta-lactams permeate the P. aeruginosa outer membrane via newly identified porins.
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research-article |
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Toyoda Y, Miwa I, Satake S, Anai M, Oka Y. Nuclear location of the regulatory protein of glucokinase in rat liver and translocation of the regulator to the cytoplasm in response to high glucose. Biochem Biophys Res Commun 1995; 215:467-73. [PMID: 7487979 DOI: 10.1006/bbrc.1995.2488] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Rat liver is known to contain a regulatory protein (RP) that inhibits glucokinase competitively with respect to glucose. By an immunohistochemical technique and by cell fractionation in glycerol, we investigated the distribution of RP in rat liver and its changes in response to high glucose. RP was detected almost exclusively in the nuclei of the parenchymal cells of both fed and fasted rats. In situ perfusion of the liver with 20 mM glucose for 10 min caused a marked decrease in nuclear RP and an increase in cytoplasmic RP. These results indicate that RP is present predominantly in the nuclei of hepatocytes and is translocated from the nucleus to the cytoplasm in response to high glucose.
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Tanaka K, Satake S, Saito S, Takahashi S, Hiroe Y, Miyashita Y, Tanaka S, Tanaka M, Watanabe Y. A new radiofrequency thermal balloon catheter for pulmonary vein isolation. J Am Coll Cardiol 2001; 38:2079-86. [PMID: 11738318 DOI: 10.1016/s0735-1097(01)01666-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES We sought to evaluate whether porcine pulmonary vein (PV) isolation (PVI) can be produced by ablation using our novel radiofrequency (RF) thermal balloon catheter (RBC). BACKGROUND It has been proposed that PVI can prevent focal atrial fibrillation (AF) originating in or close to the PV. METHODS The RBC is composed of a 12F main shaft, a 4F inner tube and a balloon. Inside the balloon, there is a unipolar coil electrode with a thermocouple sensor mounted along the tube, the former to deliver RF energy (13.56 MHz) and the latter to monitor the temperature. After the presence of a PV potential was confirmed, the RBC was safely inserted into the left atrium (LA) by the trans-septal approach. Once the balloon was inflated and optimally wedged at the junction between the PV and LA, RF energy was applied for 5 min. Radiofrequency catheter ablation (RFA) was repeated up to three times, until elimination of the PV potential or dissociation between the LA and PV was observed. Finally, each heart was examined histologically. RESULTS In 18 PVs that had PV potentials, PVI was performed, resulting in success in 15 (success rate 83%, 95% confidence interval [CI] 58.0% to 96.3%; failure rate 17%, 95% CI 3.7% to 42.0%). After successful PVI, the PV potentials completely disappeared and the histologic examination revealed circumferential, transmural necrosis around the PV trunks. No major complications, such as PV stenosis or macroscopic thrombosis, were observed. CONCLUSIONS The RBC was useful for PVI.
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Shime N, Satake S, Fujita N. De-escalation of antimicrobials in the treatment of bacteraemia due to antibiotic-sensitive pathogens in immunocompetent patients. Infection 2011; 39:319-25. [PMID: 21509424 DOI: 10.1007/s15010-011-0116-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Accepted: 03/31/2011] [Indexed: 01/10/2023]
Abstract
BACKGROUND The aim of this study was to examine the safety and efficacy of de-escalating antimicrobial therapy in immunocompetent patients presenting with bacteraemia due to antibiotic-sensitive pathogens. METHODS We screened 1,350 positive blood cultures identified in a single, 1,065-bed university hospital over 5 years, and retained 310 cases of bacteraemia due to antibiotic-sensitive pathogens, including (1) methicillin-sensitive staphylococci, (2) penicillin-sensitive streptococci, (3) β-lactam-sensitive (a) Escherichia coli, and (b) Klebsiella species. The efficacy of appropriate initial empirical antimicrobial therapy, the performance of de-escalated pathogen-directed therapy, and the safety and efficacy of de-escalated therapy were evaluated. RESULTS Among 270 appropriately treated patients, 16 (6%) died, versus 6 (15%) among 40 who were inappropriately treated (p = 0.04). While 201 of 270 patients (74%) who received appropriate initial empirical therapy were candidates for de-escalation, the treatment was de-escalated in only 79 (39%). De-escalation was associated with (1) a trend toward a lower (a) death rate (1 vs. 5%) and (b) treatment failure (4 vs. 10%), and (2) (a) a 4-day longer median duration and (b) a $50 higher median cost of antimicrobial therapy (p < 0.001). CONCLUSIONS When the pathogen was sensitive to antimicrobial therapy and the initial empirical treatment was effective, de-escalation of antimicrobial therapy in immunocompetent patients with bacteraemia was safe and associated with acceptable outcomes. The rate of de-escalation of antimicrobial therapy was low.
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Research Support, Non-U.S. Gov't |
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Satake S, Yoneyama H, Nakae T. Role of OmpD2 and chromosomal beta-lactamase in carbapenem resistance in clinical isolates of Pseudomonas aeruginosa. J Antimicrob Chemother 1991; 28:199-207. [PMID: 1778851 DOI: 10.1093/jac/28.2.199] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Imipenem-resistant clinical isolates of Pseudomonas aeruginosa were divided into two categories: (i) isolates that were moderately resistant to imipenem (MIC 6.25 mg/L) that produced trace amounts of protein D2 detected with immunoblotting using anti-protein D2 antibody, but not when stained with Coomassie blue and had inducible class 1 beta-lactamase expression; (ii) isolates that were highly resistant to several beta-lactams, including meropenem, with no protein D2 by staining or immunoblotting and had stably derepressed beta-lactamase. Laboratory strains were isolated and analyzed: (i) mutants lacking protein D2, or (ii) lacking protein D2 and producing stably derepressed beta-lactamase with carbapenem resistance similar to the clinical isolates. (iii) mutants producing undetectable beta-lactamase which were four-fold more susceptible to imipenem than the mutant producing stably derepressed beta-lactamase or the strain with inducible beta-lactamase. These data suggests that beta-lactamase and outer membrane permeability govern meropenem-resistance in P. aeruginosa.
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Dai JL, Mizoguchi A, Satake S, Ishizaki H, Gilbert LI. Developmental changes in the prothoracicotropic hormone content of the Bombyx mori brain-retrocerebral complex and hemolymph: analysis by immunogold electron microscopy, quantitative image analysis, and time-resolved fluoroimmunoassay. Dev Biol 1995; 171:212-23. [PMID: 7556897 DOI: 10.1006/dbio.1995.1272] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The insect brain neuropeptide, prothoracicotropic hormone (PTTH), elicits the molting process by stimulating ecdysteroidogenesis in the prothoracic glands. Changes in the subcellular distribution of PTTH during the fifth larval instar and larval-pupal metamorphosis of Bombyx were investigated using immunogold electron microscopy and computerized image analysis. A time-resolved fluoroimmunoassay was employed to quantify the hemolymph PTTH titer and the hemolymph ecdysteroid titer was determined by radioimmunoassay. Immunoreactivity was apparent only in the cytoplasm of two pairs of dorsal-lateral neurosecretory cells (La) in the brain, the prothoracicotropes, and their axons that traverse the peripheral area of the brain neuropil and then enter the neurohemal lobes of the corpora cardiaca and end in the corpora allata. Immunospecificity was evident as noted by the restriction of the 5-nm gold particles to the neurosecretory granules. Synaptic contacts were noted frequently between the dendritic collaterals of the prothoracicotropes and neighboring collaterals from other neurons. The morphological data suggest that PTTH is synthesized and released throughout the fifth larval instar. The concentration of gold particles in the neurosecretory granules and the number of neurosecretory granules increased five times during the fifth instar, and these increases were correlated with surges in the hemolymph PTTH and ecdysteroid titers. The data suggest that PTTH biosynthesis, secretory granule formation, and secretion are three continuous and almost synchronized events.
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