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Naka K, Sasaki H, Furuta M, Nanjo K. [Clinical significance of auditory brain stem response in the diagnosis of diabetes and their complications]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 1990; 48 Suppl:618-24. [PMID: 2086943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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102
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Okada Y, Naka K, Minamoto T, Ueda Y, Oda Y, Nakanishi I, Timpl R. localization of type VI collagen in the lining cell layer of normal and rheumatoid synovium. J Transl Med 1990; 63:647-56. [PMID: 2232713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Types I to VI collagens were immunolocalized in normal and rheumatoid synovium using monospecific antibodies. Immunofluorescence studies showed type VI in the extracellular matrix of the lining cell layer, whereas positive staining for type III collagen was observed in both the lining and sublining cell layers. All other collagens could not be detected in the lining cell layer. Immunogold staining of the rheumatoid synovium localized type VI collagen to filamentous material, which was the major extracellular structure of the lining cell layer. Type III collagen was associated with thin cross-striated collagen fibrils. A brief treatment of rheumatoid synovial tissue with bacterial collagenase produced in the lining cell layer numerous broad-banded fibrils with 100-nm periodicity; these fibrils could be labeled with the antibody against type VI collagen. This suggests that type VI collagen filaments have the potential to form periodic structures under certain conditions. We further studied the susceptibility of type I to VI collagens to matrix metalloproteinase 1, 2 and 3 (collagenase, gelatinase of molecular weight 72,000, stromelysin), which are secreted by synovial lining cells in rheumatoid synovium, and found only type VI collagen to be completely resistant to all these metalloproteinases. These data indicate that type VI collagen, which has the ability to bind to cells and to interstitial collagens, plays an important role in supporting the synovial lining cells in the normal and rheumatoid synovium.
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103
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Shimojo N, Naka K, Nakajima C, Ishizaki T, Okuda K, Murai J, Yamamoto M. The effect of non-insulin-dependent diabetes on serum concentrations of tumor-associated carbohydrate antigens of CA19-9, CA-50, and sialyl SSEA-1 in association with the Lewis blood phenotype. Clin Chim Acta 1990; 190:283-9. [PMID: 1979260 DOI: 10.1016/0009-8981(90)90182-r] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Serum concentrations of the tumor-associated carbohydrate antigens CA19-9, CA-50, and sialyl SSEA-1 were measured in non-insulin-dependent diabetic patients without diseases causing the elevation of those antigens, and the relationship to diabetic conditions was studied. The patients of the Lewis blood group phenotype of Lea (23%) had higher serum CA19-9, CA-50, and sialyl SSEA-1 than those of Leb (67%) and Le(-) (10%). Lea patients with high HbA1c (greater than 10%) had significantly higher serum CA19-9 and CA-50 than those with low HbA1c (less than or equal to 7%). Leb patients with high HbA1c also had elevated CA19-9 and sialyl SSEA-1. In Leb patients, diabetic nephropathy was associated with increased CA19-9 levels. Diabetic retinopathy was also accompanied by high carbohydrate antigens in Leb patients, but the difference was not significant. Leb patients treated with sulfonylurea or insulin had increased CA19-9 and CA-50. The changes in serum concentrations of these carbohydrate antigens might have some relationship not only to the Lewis blood phenotype, but also to diabetes.
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104
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Ishiko O, Deguchi M, Tatsuta I, Naka K, Hirai K, Nakata S, Honda K, Sugawa T. Removal of immunosuppressive substance in cancer patients' serum. Jpn J Cancer Res 1990; 81:564-6. [PMID: 2119358 PMCID: PMC6504049 DOI: 10.1111/j.1349-7006.1990.tb02609.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Anemia-inducing substance (AIS) appears in plasma as cancer progresses. In this study, a non-coated charcoal column was used to remove AIS from the cachectic plasma obtained from patients with advanced cancer. AIS could be completely removed by 6 cycles of adsorption using this column. Similar data were obtained in an experiment using VX-2-transplanted rabbits. These observations raised the possibility that plasmapheresis with a non-coated charcoal column may be available as a new means of immunotherapy for advanced cancer.
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105
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Kuwajima S, Matsui T, Kitahashi S, Kishida T, Noda T, Izumi Y, Naka K, Okuda K. Automated measurement of trypsin inhibitor in urine with a centrifugal analyzer: comparison with other acute phase reactants. Clin Biochem 1990; 23:167-71. [PMID: 1695557 DOI: 10.1016/0009-9120(90)80031-d] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Automated measurement of trypsin inhibitor in urine was performed with good precision using the COBAS FARA. Elevated levels of both trypsin inhibitor in urine and acute phase proteins in serum were shown in most cases of major abdominal surgery. We suggest that the automated assay of urinary trypsin inhibitor might be useful for the clinical diagnosis of acute phase response.
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106
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Yoshikawa C, Shimojo N, Naka K, Okuda K, Ohkawa J. Separation of hepatoma-associated gamma-glutamyltransferase isoenzyme on cellulose acetate media with Triton X-100 and concanavalin A. Clin Chim Acta 1989; 185:317-23. [PMID: 2575935 DOI: 10.1016/0009-8981(89)90222-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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107
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Ohi G, Kai I, Ichikawa S, Miyama T, Naka K. Psychotic manifestations in the bed-fast elderly--a preliminary communication. JOURNAL OF HUMAN ERGOLOGY 1989; 18:237-40. [PMID: 2534662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In order to examine a hypothesis that bed-fast elderly tend to develop psychotic manifestations more often when they are under greater environmental stress, we have devised a caretaker-patient relationship score (CPR score) to measure the relationship between the elderly and their principal caretakers. Our study in three areas of Japan demonstrated that in each area the occurrence of the psychotic manifestations is greater in the group with poor CPR scoring, suggesting that the greater the environmental stress the more frequently psychotic manifestations occur.
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Abstract
Cone horizontal cells from the catfish retina extend out processes after a few days in culture that sometimes contact adjacent cone horizontal cells. Two types of specialized junctions were observed by electron microscopy along the newly formed contact areas. One junctional type consisted of prominent electron-dense material along and just under the plasma membrane of one or both of the contacting elements. Sometimes vesicle clusters were associated with these junctions. The other type of junction showed some electron-dense material along the membranes of both processes and patchy areas of close membrane apposition resembling gap junctions. In about half of the cases tested, electrical coupling was detected between cone horizontal cells that had made contact in culture. In no case was the coupling as tight as is typically found between horizontal cells that had formed gap junctions in vivo.
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109
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Shimojo N, Naka K, Nakajima C, Yoshikawa C, Okuda K, Okada K. Test-strip method for measuring lactate in whole blood. Clin Chem 1989; 35:1992-4. [PMID: 2776334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We have developed a dry reagent strip system for measuring lactate in whole blood. The test strip contains lactate oxidase (no EC number assigned), horseradish peroxidase (EC 1.11.1.7), and N-ethyl-N-(2-hydroxy-3-sulfopropyl)-m-toluidine. The system is designed to measure with a reflectometer the color that developed in the test strip, although the lactate concentration can be estimated without the reflectometer. The between-run coefficients of variation for controls at three concentrations were 2.9-5.3%. The lactate concentrations in blood samples from healthy subjects before and after exercise correlated well (r = 0.97) with the results measured by the comparison method with the use of lactate oxidase. This dry reagent strip system provides a convenient and rapid test for measuring blood lactate in clinical and sports medicine.
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110
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Shimojo N, Naka K, Nakajima C, Yoshikawa C, Okuda K, Okada K. Test-strip method for measuring lactate in whole blood. Clin Chem 1989. [DOI: 10.1093/clinchem/35.9.1992] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
We have developed a dry reagent strip system for measuring lactate in whole blood. The test strip contains lactate oxidase (no EC number assigned), horseradish peroxidase (EC 1.11.1.7), and N-ethyl-N-(2-hydroxy-3-sulfopropyl)-m-toluidine. The system is designed to measure with a reflectometer the color that developed in the test strip, although the lactate concentration can be estimated without the reflectometer. The between-run coefficients of variation for controls at three concentrations were 2.9-5.3%. The lactate concentrations in blood samples from healthy subjects before and after exercise correlated well (r = 0.97) with the results measured by the comparison method with the use of lactate oxidase. This dry reagent strip system provides a convenient and rapid test for measuring blood lactate in clinical and sports medicine.
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111
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Korenberg MJ, Sakai HM, Naka K. Dissection of the neuron network in the catfish inner retina. III. Interpretation of spike kernels. J Neurophysiol 1989; 61:1110-20. [PMID: 2746312 DOI: 10.1152/jn.1989.61.6.1110] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
1. Three independent sets of evidence have been obtained to show that similar first- and second-order light-evoked kernels are computed for the ganglion cell when the system output is taken to be either the spike train (discrete signal) or the postsynaptic potential (analog signal). In this paper we show that the similarity of postsynaptic potential (PSP) kernels and spike kernels is readily explained by assuming an underlying cascade structure for the neural information processing. The cascade structure enables spike kernels to be mathematically related very simply to the process of generating the postsynaptic potentials of ganglion cells. 2. Mathematical analysis of the cascade structure also suggests why spike kernels appear to differ slightly from PSP kernels. The relation between the two sets of kernels predicted from our analysis is substantiated here by experiment and reveals an interconnection between several of the signals measured. 3. Our experimental results, in particular, suggest that the neuronal circuitry leading from the light stimulus to the generation of ganglion cell spike discharges can be represented as follows: either a Wiener (LN) or a dynamic linear-static nonlinear-dynamic linear (LNL) structure is followed by a highly nonlinear process [static or brief-memory Hammerstein static-nonlinear dynamic-linear (NL) structure] of spike generation. Cross-correlation between the analog input and spike output enables identification of these structures.
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112
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Naka K, Motoki K, Ootani H, Naka Y. [Long-term follow-up of thallium-201 myocardial scintigraphy in acute myocardial infarction--clinical significance of reverse redistribution during acute period]. KAKU IGAKU. THE JAPANESE JOURNAL OF NUCLEAR MEDICINE 1989; 26:539-43. [PMID: 2770044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
To clarify the viability of myocardium in acute myocardial infarction, we examined 18 patients scintigraphically. They underwent rest or stress imaging and delayed imaging of thallium-201 during acute, convalescent and chronic periods. During acute period, a scintigraphic finding of the delayed filling in was observed in 9 cases (50%; Redistribution group). Worsening of the delayed image was observed in 6 cases (33%; Reverse redistribution group). No scintigraphic change of the perfusion defect was observed in 3 cases (17%; No change group). In reverse redistribution group, a remarkable improvement of the delayed image was observed through acute, convalescent and chronic periods. In redistribution group and no change group, no significant improvement was observed. We conclude that the myocardium of the reverse redistribution region during acute period may be viable. In the reverse redistribution region, recanalization of the coronary artery possibly protects myocardial damage from necrosis.
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113
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Abstract
The all-rod retina of the skate (Raja erinacea or R. oscellata) is known to have the remarkable capability of responding to incremental flashes superimposed on background intensities that initially block all light-evoked responses and are well above the level at which rods saturate in mixed rod/cone retinas. To examine further the unusual properties of the skate visual system, we have analyzed responses of their horizontal cells to intensity-modulated step, sinusoidal, and white-noise stimuli. We found that during exposures to mean intensities bright enough to block responses to incremental stimuli, decremental stimuli were also initially blocked. Thereafter, the horizontal cells underwent a slow recovery phase during which there was marked nonlinearity in their response properties. The cell first (within 2-3 min) responded to decrements in intensity and later (after greater than 10 min) became responsive to incremental stimuli. After adaptation to a steady state, however, the responses to intensity modulation were nearly linear over a broad range of modulation depths even at the brightest mean levels of illumination. Indeed, examination of the steady-state responses over a 5-log-unit range of mean intensities revealed that the amplitude of the white noise-evoked responses depended solely on contrast, and was independent of the retinal irradiance as the latter was increased from 0.02 to 20 muW/cm2; i.e., contrast sensitivity remained unchanged over this 1,000-fold increase in mean irradiance. A decrement from the mean as brief as 2 s, however, disturbed the steady state. Another unexpected finding in this all-rod retina concerns surround-enhancement, a phenomenon observed previously for cone-mediated responses of horizontal cells in the retinas of turtle and catfish. While exposure to annular illumination induced response compression and a pronounced sensitivity loss in response to incremental light flashes delivered to the dark central region, the cell's sensitivity showed a significant increase when tested with a white noise or sinusoidally modulated central spot. Unlike horizontal cells in other retinas studied thus far, however, response dynamics remained unchanged. Responses evoked either by a small spot (0.25-mm diam) or by a large field light covering the entire retina were almost identical in time course. This is in contrast with past findings from cone-driven horizontal cells whose response waveform (dynamics) was dependent upon the size of the retinal area stimulated.
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114
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Sakai HM, Naka K. Dissection of the neuron network in the catfish inner retina. I. Transmission to ganglion cells. J Neurophysiol 1988; 60:1549-67. [PMID: 2848933 DOI: 10.1152/jn.1988.60.5.1549] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
1. To characterize the signal transmission from amacrine to ganglion cells, and to identify the filter that transforms amacrine-cell responses into ganglion-cell spike discharges, an extrinsic current, either sinusoidally or white-noise modulated, was injected into an amacrine cell and the resulting extracellular spike discharges were recorded from a neighboring ganglion cell. For the sinusoidal inputs, PST (poststimulus time) histograms were produced; for the white-noise inputs, first- and second-order Wiener kernels were computed by a cross-correlation process. 2. Extrinsic current injected either into a type-N (sustained) amacrine cell or a type-C (transient) amacrine cell modulated the spike discharges of nearby ganglion cells, whether of the "ON," "ON-OFF" or "OFF" types. We identified two modes of signal transmission, fast (probably monosynaptic) and slow (probably polysynaptic) transmission. Signal transmission from amacrine to ganglion cells of the same response polarity i.e., from type-NA (depolarizing, sustained) amacrine to ON-ganglion cell and from-NB (hyperpolarizing, sustained) amacrine to OFF-ganglion cell, was either fast or slow. Similarly, the signal transmission from type-C to either ON- or OFF-ganglion cells was either fast or slow. 3. The signal transmission from amacrine to ganglion cell of the opposite response polarity, i.e., from type-NA to OFF-ganglion cell and from type-NB to ON-ganglion cell, was always slow. 4. Fast transmission from type-N amacrine to a ganglion cell of the same polarity, or from type-C to either ON- or OFF-ganglion cells was always sign-noninverting. The transfer function was lowpass, with a cutoff frequency of 30 Hz. 5. Slow transmission from any type of amacrine cell (either type-NA, -NB or -C) to ON-ganglion cells was always sign inverting, whereas from any amacrine to OFF-ganglion cells was always sign-noninverting. The transfer function for the slow transmission was narrow bandpass, with a cutoff frequency of 30-40 Hz.
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115
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Sakai HM, Naka K. Dissection of the neuron network in the catfish inner retina. II. Interactions between ganglion cells. J Neurophysiol 1988; 60:1568-83. [PMID: 2848934 DOI: 10.1152/jn.1988.60.5.1568] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
1. To characterize signal interactions between ganglion cells, extrinsic current, either sinusoidally or white-noise modulated, was injected into a ganglion cell and the resulting extracellular spike discharges were recorded from a neighboring ganglion cell. 2. Current injected into an ON-ganglion (GA) cell modulated the spike discharges of a neighboring ON-ganglion cell (GA). Similarly, a current injected into an OFF-ganglion (GB) cell modulated the spike discharges of a neighboring OFF-ganglion (GB) cell. The signal transmission between ganglion cells of the same response polarity was fast and sign-noninverting. The transfer function was lowpass with a cutoff frequency of 30 Hz. The efficacy of the transmission was comparable to that from bipolar or amacrine to ganglion cells of the same polarity. 3. Current injected into an ON-ganglion (GA) cell modulated the spike discharges of a neighboring OFF-ganglion (GB) cell; the signal transmission was slow and sign-noninverting. Correspondingly, current injected into an OFF-ganglion (GB) cell modulated the spike discharges of a neighboring ON-ganglion (GA) cell; transmission was slow and sign-inverting. 4. A brief electrical stimulation of the optic nerve activated a single antidromic ganglion cell spike at threshold. With suprathreshold stimulation, multiple spikes appeared, which probably were activated orthodromically. Changes in membrane potential of ganglion and amacrine cells induced by optic nerve stimulation usually lasted 50-80 ms, with an initial depolarization followed by hyperpolarization. We interpret such long-lasting responses to be mediated by reciprocal circuits that include amacrine, bipolar, and ganglion cells. 5. Together with the observations made by Sakai and Naka, we conclude that virtually almost all amacrine, bipolar, and ganglion cells are functionally interconnected; direct and fast connections are established among ON-cells and similarly among OFF-cells, and complex, indirect connections are established between ON- and OFF-cells.
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Yasuda M, Nishikimi T, Akioka K, Teragaki M, Oku H, Takeuchi K, Takeda T, Naka K, Okuda K, Ikuno Y. Relationship between cardiac function and the sympathetic nervous system during exercise in patients with essential hypertension. JAPANESE CIRCULATION JOURNAL 1988; 52:1121-31. [PMID: 3210290 DOI: 10.1253/jcj.52.1121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The relationship between echographical cardiac function and sympathetic nerve activity during dynamic exercise was examined in patients with essential hypertension. Nine normotensives (Group N), 11 hypertensive patients without cardiac hypertrophy (Group NH) and 13 hypertensive patients with cardiac hypertrophy (Group HH) were studied during multistage exercise using a supine bicycle ergometer. The shortening fraction (SF) and the peak negative dD/dt in Group HH, being within the normal range, tended to be smaller than those in Group N at the 75-watt load. The mean value of the peak positive dD/dt (+dD/dt) in Group HH was significantly smaller than that in Group N at rest and during the 75-watt load. The percent increase of plasma norepinephrine (NE) levels (% delta NE) at the 75-watt load was significantly greater in Group HH than in Group N. Plasma NE, in some patients with cardiac hypertrophy and compromised cardiac function, markedly increased (% delta NE greater than or equal to 186) during exercise. % delta NE was directly related to the left ventricular mass index among all of the groups, but it was inversely related to the SF, -dD/dt, and to +dD/dt at the 75-watt load. We conclude that the augmented sympathetic nerve activity may contribute to preserving left ventricular systolic function during exercise within the normal range in hypertensive patients with cardiac hypertrophy.
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117
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Shimojo N, Hirai M, Naka K, Yoshikawa C, Okuda K, Aono S, Isshiki G, Fujii S. Plasma fructosamine assay in children with insulin-dependent diabetes mellitus. Clin Chim Acta 1988; 176:101-6. [PMID: 3168288 DOI: 10.1016/0009-8981(88)90179-9] [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: 01/04/2023]
Abstract
Plasma concentrations of fructosamine, an indicator of glycated plasma proteins, were measured in non-diabetic children and children with insulin-dependent diabetes mellitus (IDDM) to see if they also correlate with glycemic control in children as well as in adults. Non-diabetic children aged less than 4 yr had significantly lower plasma fructosamine than non-diabetic children aged 4 or more. Total plasma protein in these children was slightly lower or close to that of older children. There was no difference in fructosamine between non-diabetic children aged 4 or more and healthy adult subjects. Plasma fructosamine in children with IDDM was twofold that of age-matched controls. In children with IDDM, correlations between fructosamine and HbAI (r = 0.799) or HbAIc (r = 0.841) were high. The measurement of plasma fructosamine, which is practical in children because of the small sample volume needed and no influence of HbF, is useful in the management of children with IDDM.
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118
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Hirai M, Kobayashi N, Shimojo N, Naka K, Yoshikawa C, Okuda K, Aono S. [Measurement of plasma fructosamine in children with insulin-dependent diabetes mellitus]. RINSHO BYORI. THE JAPANESE JOURNAL OF CLINICAL PATHOLOGY 1988; 36:939-42. [PMID: 3071634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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119
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Ikeda T, Motoki K, Maeda T, Naka K, Ootani H, Hamaji J, Ichinosawa A, Komai H, Takimoto M, Naito Y. [Successful case report concerning removal of right atrial tumor of malignant thymoma--review of right atrial tumor thrombus via the superior or inferior vena cava]. NIHON NAIKA GAKKAI ZASSHI. THE JOURNAL OF THE JAPANESE SOCIETY OF INTERNAL MEDICINE 1988; 77:1025-30. [PMID: 2853197 DOI: 10.2169/naika.77.1025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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120
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Abstract
In 1827, plant biologist Robert Brown discovered what is known as Brownian motion, a class of chaos. Formal derivative of Brownian motion is Gaussian white-noise. In 1938, Norbert Wiener proposed to use the Gaussian white-noise as an input probe to identify a system by a series of orthogonal functionals known as the Wiener G-functionals. White-noise analysis is uniquely suited for studying the response dynamics of retinal neurons because (1) white-noise light stimulus is a modulation around a mean luminance, as are the natural photic inputs, and it is a highly efficient input; and (2) the analysis defines the response dynamics and can be extended to spike trains, the final output of the retina. Demonstrated here are typical examples and results from applications of white-noise analysis to a visual system.
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121
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Sasaki H, Nanjo K, Yamada M, Naka K, Bessho H, Kikuoka H, Satogami E, Matsumoto G, Emoto M, Miyamura K. Diabetic neuropathy as a heterogeneous syndrome: multivariate analysis of clinical and neurological findings. Diabetes Res Clin Pract 1988; 4:215-22. [PMID: 3359922 DOI: 10.1016/s0168-8227(88)80021-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We quantitatively assessed peripheral and autonomic nerve function in diabetic patients and compared them with various parameters of their diabetic status. Motor and sensory nerve conduction velocity (MCV, SCV), vibratory perception threshold (VPT) and the coefficient of variation of the ECG R-R interval (CV R-R) were measured in 85 diabetic patients aged 20-59 years. These values were compared with those of age-matched healthy subjects. Moreover, in 53 patients, MCV, SCV, VPT and CV R-R were investigated by multivariate analysis in relation to clinical parameters. In diabetics, MCV, SCV and CV R-R were significantly lower and VPT was higher than in age-matched healthy controls. The prevalence of impaired values in diabetics was 70% for VPT in the toe, 60% for SCV, and 55% for MCV, CV R-R and VPT in the finger. Impairments of MCV, SCV, CV R-R and VPT were closely correlated with diabetic retinopathy, proteinuria and duration of disease. Categorical regression analysis (multivariate analysis) revealed that the impairment of conduction velocity was closely related to diabetic retinopathy and to hypo- or areflexia, that the impairment of the vibratory perception threshold was related to ischemic changes in ECG and to hypo- or areflexia, and that the reduction of CV R-R was related to orthostatic hypotension and to proteinuria. These findings suggest that diabetic neuropathy progresses in parallel with other complications, and that it is a heterogeneous syndrome rather than a single entity.
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122
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Yoshikawa C, Shimojo N, Naka K, Akai T, Okuda K, Kaminou T, Yamada T, Nakatsuka H. Changes in serum enzyme activity after transcatheter arterial embolization for hepatic neoplasm. Clin Biochem 1987; 20:435-40. [PMID: 2830050 DOI: 10.1016/0009-9120(87)90011-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We assayed serum levels of certain enzymes and tumor markers in patients after transcatheter arterial embolization (TAE) to evaluate the effectiveness of this treatment. Twenty patients had hepatocellular carcinoma and two patients had metastases to the liver from colon cancer. Assays were first done immediately after TAE and were continued for the next 12 days. Glutamic oxaloacetic transaminase (GOT; EC 2.6.1.1, L-aspartate:2-oxoglutarate aminotransferase), glutamic pyruvic transaminase (GPT; EC 2.6.1.2, L-alanine:2-oxoglutarate aminotransferase), and lactate dehydrogenase (EC 1.1.1.27; (S)-lactate:NAD+ oxidoreductase) peaked 24 to 48 h after TAE and returned to the base lines in 7 to 10 days. Mitochondrial GOT (mGOT) and glutamate dehydrogenase (GLDH; EC 1.4.1.2, L-glutamate:NAD+ oxidoreductase) also peaked at the same time after TAE. alpha-Fetoprotein peaked 2 h after TAE and decreased to half of the baseline on day 7. Carcinoembryonic antigen peaked at 24 h and fell at 48 h only in the patients with colon cancer. The total amount of cytosolic GOT, GPT, mGOT, and GLDH released was correlated to the volume of the necrotic mass estimated by computed tomography scans. The correlation coefficients for mGOT and GLDH were r = 0.919 and r = 0.939 (both p less than 0.001), respectively. Assays of mGOT and GLDH may be useful to estimate the volume of the necrotic mass of a hepatoma or metastatic carcinoma in the liver.
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123
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Sakai HM, Naka K. Signal transmission in the catfish retina. IV. Transmission to ganglion cells. J Neurophysiol 1987; 58:1307-28. [PMID: 2830370 DOI: 10.1152/jn.1987.58.6.1307] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
1. To characterize the temporal dynamic responses of ganglion cells and to define the possible inputs giving rise to their responses in catfish retina, we recorded the ganglion cell responses evoked by 1) a step of light presented in the dark, 2) an incremental and decremental step from a background illumination, and 3) a white-noise modulated light. 2. For comparison, we recorded the responses of preganglionic cells evoked by the same set of stimuli as used for the ganglion cells. Type-C cells produced on-off transient depolarizations to step stimuli, whether presented in the dark or an illuminated background. Type-N amacrine cells produced complex transient responses to incremental and decremental steps, whereas their step-evoked responses in the dark were sustained polarizations. Bipolar cells produced sustained responses to all step stimuli. 3. Ganglion cells were classified into three types, based on their responses evoked by incremental and decremental steps of light. One class of ganglion cells produced responses similar to those of type-C cells, the second class produced responses similar to those of type-N cells, and the third class resembled bipolar cell responses, although spike discharges accompanied the ganglion cell responses. 4. The analysis of the first-order kernels indicates that the temporal properties of linear dynamic responses are established at the level of bipolar cells and encoded into spike trains of ganglion cells without a major transformation. 5. The second-order nonlinearity appeared at the amacrine cell level. Type-C and type-N cells produced a second-order kernel characteristic of each cell type. The second-order kernels produced in ganglion cells were similar to those produced either by type-C or type-N cells. 6. We conclude that bipolar cells are the major source of linear components of ganglion cell responses and that type-C and type-N amacrine cells are the major source of the nonlinear responses. These linear and second-order nonlinear signals were encoded into spike trains by ganglion cells without a major transformation of the temporal response properties.
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Abstract
1. We analyzed the light-evoked responses of retinal neurons by means of a white-noise technique. Horizontal and bipolar cells produced a modulation response that was linearly related to a modulation of the mean luminance of a large field of light. The first-order kernels were capable of reproducing the cells' modulation response with a fair degree of accuracy. The amplitude as well as the waveform of the kernels changed with the change in the mean luminance. This is a parametric change and is a form of field adaptation. As the time constant of the parametric change was much longer than that of the modulation response (memory), neurons were assumed to be at a dynamic steady state at a given mean luminance. 2. With the presence of a steady annular illumination, the first-order kernel derived from stimulation with a small spot of light became faster in peak response time and larger in amplitude. For horizontal-cell somas and bipolar cells, the surround also linearized their modulation response. This surround enhancement has been seen in all the cone-driven retinal cells except the receptor and horizontal cell axon, in which a steady surround decreased the amplitude of the spot-evoked kernel but shortened the peak response time. 3. A change in the modulation depth did not affect either the amplitude or the wave-form of the first-order kernels from the horizontal and bipolar cells. In the amacrine and ganglion cells, on the other hand, the amplitude of kernels was related inversely to the depth of modulation. These cells were more sensitive to the modulation of a small modulation depth. 4. A static nonlinearity appeared when signals were transmitted to the amacrine cells. The nonlinearity was first produced in the type-C amacrine cells by a process, which could be modeled by squaring the bipolar cell response. A gamut of more complex second-order nonlinearities found in type-N amacrine cells could be modeled by a band-pass filtering of the type-C cell response. Linear components in the bipolar cells and nonlinear components in the amacrine cells are encoded into spike trains in the ganglion cells. Thus, under our simple stimulus regimen, the ganglion cells transformed the results of the preganglionic signal processing into a spike train without much modification. 5. We propose a tentative diagram of the signal flow in the cone-driven catfish retinal neurons based on this and previous studies.(ABSTRACT TRUNCATED AT 400 WORDS)
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Sakuranaga M, Ando Y, Naka K. Dynamics of the ganglion cell response in the catfish and frog retinas. J Gen Physiol 1987; 90:229-59. [PMID: 3498795 PMCID: PMC2228836 DOI: 10.1085/jgp.90.2.229] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Responses were evoked from ganglion cells in catfish and frog retinas by a Gaussian modulation of the mean luminance. An algorithm was devised to decompose intracellularly recorded responses into the slow and spike components and to extract the time of occurrence of a spike discharge. The dynamics of both signals were analyzed in terms of a series of first-through third-order kernels obtained by cross-correlating the slow (analog) or spike (discrete or point process) signals against the white-noise input. We found that, in the catfish, (a) the slow signals were composed mostly of postsynaptic potentials, (b) their linear components reflected the dynamics found in bipolar cells or in the linear response component of type-N (sustained) amacrine cells, and (c) their nonlinear components were similar to those found in either type-N or type-C (transient) amacrine cells. A comparison of the dynamics of slow and spike signals showed that the characteristic linear and nonlinear dynamics of slow signals were encoded into a spike train, which could be recovered through the cross-correlation between the white-noise input and the spike (point process signals. In addition, well-defined spike correlates could predict the observed slow potentials. In the spike discharges from frog ganglion cells, the linear (or first-order) kernels were all inhibitory, whereas the second-order kernels had characteristics of on-off transient excitation. The transient and sustained amacrine cells similar to those found in catfish retina were the sources of the nonlinear excitation. We conclude that bipolar cells and possibly the linear part of the type-N cell response are the source of linear, either excitatory or inhibitory, components of the ganglion cell responses, whereas amacrine cells are the source of the cells' static nonlinearity.
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