Biomedical subjects

M Okazaki

Publications and source records attributed to M Okazaki.

At least 37 records · Page 2Linked to original sources

PubMed2003

The mechanism of epidermal hyperpigmentation in café-au-lait macules of neurofibromatosis type 1 (von Recklinghausen's disease) may be associated with dermal fibroblast-derived stem cell factor and hepatocyte growth factor.

BACKGROUND: The mechanism of the accentuated melanization in café-au-lait macules (CALMs) in patients with neurofibromatosis type 1 (NF1; von Recklinghausen's disease) has not been elucidated. OBJECTIVES: To clarify the mechanism involved in the hyperpigmentation of CALMs in NF1. METHODS: Using enzyme-linked immunosorbent assay (ELISA) and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of cultured cells, we measured the levels of cytokines produced and secreted by keratinocytes and fibroblasts derived from CALMs (group RC: Recklinghausen CALM) skin, compared with cells derived from the skin of normal individuals (group NN: Normal skin of Normal individuals) and cells derived from non-CALM skin of NF1 patients (group RN: Recklinghausen Non-CALM). RESULTS: ELISA revealed that the secretion of hepatocyte growth factor (HGF) and stem cell factor (SCF) by cultured fibroblasts was significantly elevated in group RC compared with groups RN and NN. In parallel, semiquantitative real-time RT-PCR of HGF and SCF mRNAs demonstrated increased expression of both types of transcripts by cultured fibroblasts in group RC compared with group NN. In contrast, the secretion of endothelin-1 and granulocyte/macrophage colony-stimulating factor by cultured keratinocytes occurred at a similar level among all three groups, RC, RN and NN. CONCLUSIONS: These findings suggest that increased secretion of HGF and SCF by dermal fibroblasts may be associated with the accentuated epidermal melanization observed in CALMs in the skin of NF1 patients.

Adult↗

PubMed2003

AG-041R stimulates cartilage matrix synthesis without promoting terminal differentiation in rat articular chondrocytes.

OBJECTIVE: AG-041R, a novel indolin-2-one derivative, has recently been demonstrated to induce systemic hyaline cartilage hyperplasia in rats. The aim of this study was to characterize its anabolic actions on chondrocytes. DESIGN: Chondrocytes were isolated from knee joints of 5-week-old SD rats. Effects of AG-041R on cartilage matrix synthesis were examined by measuring [(35)S]sulfate incorporation into proteoglycans, Alcian blue staining, and Northern blotting of cartilage matrix genes. ALP activity, mineral deposition and the expression of markers for hypertrophic chondrocytes, were assessed for terminal differentiation of chondrocytes. Roles of endogenous TGF-beta/BMPs and MEK1/Erk signaling in the action of AG-041R were investigated using the neutralizing soluble receptors and the MEK1 inhibitor. RESULTS: AG-041R accelerated proteoglycan synthesis assessed by both [(35)S]sulfate incorporation and Alcian blue stainable extracellular matrix accumulation. It also up-regulated the gene expression of type II collagen and aggrecan, as well as tenascin, a marker for articular cartilage. In contrast, AG-041R suppressed ALP activity, mineralization, and the gene expression of type X collagen and Cbfa1, indicating that AG-041R prevents chondrocyte terminal differentiation. AG-041R increased in BMP-2 mRNA, and the neutralizing soluble receptor for BMPs reversed the stimulatory effects of AG-041R on cartilage matrix synthesis. Moreover, AG-041R activated MEK1/Erk pathway, which was revealed to prevent chondrocyte terminal differentiation. CONCLUSION: AG-041R stimulates cartilage matrix synthesis without promoting terminal differentiation in rat articular chondrocytes, which is mediated at least in part by endogenous BMPs and Erk. The data demonstrates that AG-041R has a potential to be a useful therapeutic agent for articular cartilage disorders.

Alkaline Phosphatase↗

PubMed2003

Expression of MMP-8 and MMP-13 genes in the periodontal ligament during tooth movement in rats.

Periodontal ligament tissue is remodeled on both the tension and compression sides of moving teeth during orthodontic tooth movement. The present study was designed to clarify the hypothesis that the expression of MMP-8 and MMP-13 mRNA is promoted during the remodeling of periodontal ligament tissue in orthodontic tooth movement. We used the in situ hybridization method and semi-quantitative reverse-transcription/polymerase chain-reaction analysis to elucidate the gene expression of MMP-8 and MMP-13 mRNA. Expression of MMP-8 and MMP-13 mRNA transiently increased on both the compression and tension sides during active tooth movement in vivo. The gene expression of MMP-8 and MMP-13 was induced by tension, while compression indirectly promoted the gene expression of MMP-8 and MMP-13 through soluble factors in vitro. Thus, we concluded that the expression of MMP-8 and MMP-13 is differentially regulated by tension and compression, and plays an important role in the remodeling of the periodontal ligament.

Animals↗

PubMed2002

Biodegradation of carbonate apatite/collagen composite membrane and its controlled release of carbonate apatite.

The aim of this study was to investigate the biodegradation of carbonate apatite (CO(3)Ap)/collagen composite membrane as a new guided tissue regeneration membrane in vivo and to estimate its controlled release of CO(3)Ap in vitro. To control the biodegradation of the guided tissue regeneration membrane and to promote hard tissue regeneration in the periodontal region, we added CO(3)Ap into the collagen membrane. To investigate the biodegradation of CO(3)Ap/collagen composite membranes, the prepared membranes (CO(3)Ap:0, 10 wt %) were cut into 5 x 5 x 0.1 mm and subcutaneously implanted into the backside of male rats under general anesthesia. The explanted membranes were investigated histologically. To estimate their controlled release of CO(3)Ap in vitro, the membranes (CO(3)Ap 0-10 wt %, 5 x 5 x 0.1 mm) were immersed into collagenase solution and compulsorily dissolved for 48 h. Histological results suggested that the membrane had a good biocompatibility and the biodegradable period was shortened with the presence of CO(3)Ap. In the solubility experiments of the membrane, eluted Ca concentrations gradually increased with total dependence on the dissolution of the collagen membrane. Our study demonstrated that the biodegradation time can be controlled by CO(3)Ap contents in the membrane and CO(3)Ap could be released from the membrane with the biodegradation period.

Absorbable Implants↗

PubMed2002

Thermal analysis of dental resins cured with blue light-emitting diodes (LEDs).

Thermal analysis was used to measure the characteristics of dental resins cured with the use of a new light-activation unit equipped with high illuminant blue light-emitting diodes (LEDs). The characteristics were compared with those of resins cured with the use of two conventional halogen lamp units. The prepared base monomer consisted of a mixture of Bis-GMA and TEGDMA (60:40 by weight), with 0.5 wt% CQ/DMPT or CQ/DMAEMA. The two experimental visible-light-cured resins were polymerized for 40 s. Differential scanning calorimetry (DSC) was used to examine the thermal characteristics of the cured resins. The activation energy for the decomposition of the dental resin was calculated from the peaks of the endothermic curves obtained when the specimens were heated at three different rates (5, 10, and 15 C/min) during DSC. The activation energies calculated for the LED-cured specimens were more than 220 kJ/mol; specimens cured with the use of the halogen units had activation energies of less than 192 kJ/mol. The Knoop hardness number (KHN) of the same specimens was measured, and was higher with the blue LED units than with halogen lamp units. Therefore, dental resins cured using blue LEDs have a higher degree of polymerization and more stable three-dimensional structures than those cured with halogen lamps.

Calorimetry, Differential Scanning↗

PubMed2002

Synthesis of functionally graded MgCO3 apatite accelerating osteoblast adhesion.

As a means of improving the biological properties of materials for use as bone substitutes, functionally graded carbonate apatite containing Mg, FGMgCO3Ap, was synthesized at 60 degrees C and pH 7.4 using a gradient magnesium supply system. X-ray diffraction analysis of FGMgCO3Ap showed a poorly crystallized apatitic pattern, similar to that of human bone. ESCA analysis clearly showed the negative gradient distribution in Mg1s intensity (atomic concentration) of magnesium from the crystal surface toward the inner core. When the FGMgCO3Ap crystals were mixed with collagen, the resulting FGMgCO3Ap-collagen composite, irradiated with UV light for 4 h, retained their features in the saline solution. After washing away the nonadhesive cells, a cell adhesion assay showed that the optical density of the FGMgCO3Ap-collagen composite was higher than that of the CO3Ap-collagen composite. SEM observation showed that the osteoblast-like cells adhered well to the surface of the FGMgCO3Ap-collagen composite. Staining with hematoxylin-eosin and alizarin red confirmed the existence of a great many more cells and a thicker extracellular matrix layer on the FGMgCO3Ap-collagen composite than on the CO3Ap-collagen composite. This result demonstrated the acceleration effect of magnesium ions on osteoblast adhesion on the FGMgCO3Ap-collagen composite.

Animals↗

PubMed2002

Adhesion/decalcification mechanisms of acid interactions with human hard tissues.

In order to study adhesion/decalcification mechanisms of acid interactions with human hard tissues such as bones and teeth, the chemical interaction of five carboxylic acids (acetic, citric, lactic, maleic, and oxalic) and two inorganic acids (hydrochloric and nitric) with enamel and two synthetic hydroxyapatite (HAp) powders with, respectively, a high and a low crystallinity were analyzed using X-ray photoelectron spectroscopy (XPS), atomic absorption spectrophotometry (AAS), and spectrophotometry (S). X-ray diffraction revealed that the crystallinity of the highly crystallized HAp was considerably higher than that of enamel while the crystallinity of the poorly crystallized HAp was similar to that of dentin and bone. XPS of acid-treated enamel demonstrated for all carboxylic acids ionic bonding to calcium of HAp. AAS and S showed for both HAps that all carboxylic and inorganic acids except oxalic acid extracted Ca significantly more than P, leading to a Ca/P ratio close to that of synthetic HAp (2.16 w/w). Oxalic acid extracted hardly any Ca, but substantially more P, leading to a significantly smaller Ca/P ratio than that of HAp. AAS showed that the calcium salt of oxalic acid hardly could be dissolved, whereas the calcium salts of all the other acids were very soluble in their respective acid solution. These results confirm the adhesion/decalcification concept (AD-concept) previously advanced. Depending on the dissolution rate of the respective calcium salts, acids either adhere to or decalcify apatitic substrates. It is concluded that the AD-concept that originally dictated the interaction of carboxylic acids with human hard tissues can be extended to inorganic acids, such as hydrochloric and nitric acid. Furthermore, HAp crystallinity was found not to affect the adhesion/decalcification behavior of acids when interacting with apatitic substrates, so that the AD-concept can be applied to all human hard tissues with varying HAp crystallinity.

Acids↗

PubMed2002

Crystallinity and solubility characteristics of hydroxyapatite adsorbed amino acid.

Hydroxyapatite (HAp) was synthesized in the presence of a variety of amino acids in order to investigate the effect of amino acid on the crystallinity and the solubility characteristics of HAp in the HAp-synthesizing condition. In the results of X-ray diffraction analysis, HAp synthesized in the presence of glycine (HAp-Gly), serine (HAp-Ser), aspartic acid (HAp-Asp) and glutamic acid (HAp-Glu) showed poor crystallinity compared with HAp synthesized in the absence of amino acid (HAp-con). The results of Fourier transform infrared spectroscopy suggested the adsorption of these amino acids on HAp. Scanning electron microphotographs showed that the size and morphology of HAp adsorbed amino acids changed significantly. Furthermore, the solubility of these HAps increased significantly compared to HAp-con, each differing in four amino acids. However, other amino acids did not affect the crystallinity and morphology of HAp and had no significant change in their solubility. Collectively, this study suggests that the crystallinity and the solubility of synthesized HAp are different owing to the variation of amino acids in the HAp synthesizing condition. It is expected that digestion-regulated HAp materials could be synthesized by using amino acid in their synthesizing condition.

Adsorption↗

PubMed2002

The regional difference of viscoelastic property of bovine temporomandibular joint disc in compressive stress-relaxation.

An in vitro experimental technique was performed to measure the viscoelastic properties of the bovine disc. Thirteen TMJ discs from young cattle (3-year-old) were used. Each disc was divided into five specimens of anterior, central, posterior, lateral and medial regions, and they were used for compression tests. A series of stress-relaxation tests was conducted for each specimen from 5% strain up to 20% strain with 5% intervals. The stress-relaxation was monitored over a period of 5 min. Each region exhibited a different biomechanical behavior, which is presumably related to the organization and distribution of proteoglycans that indirectly modulate the stiffness of the collagen network. It is suggested that an improved understanding of the viscoelastic properties of the disc under function may guide consideration for design and selection of biomaterials for TMJ reconstruction.

Animals↗

PubMed2002

Improved filler-matrix coupling in resin composites.

Ineffective silane coupling between filler and matrix within dental composites is prone to accelerated in vivo degradation. In this study, we examined to what degree a procedure involving chemical decontamination of filler prior to silanization could improve the filler-matrix bonding, and thus the physico-mechanical properties, of composites. X-ray photoelectron spectroscopy revealed that filler-matrix coupling largely depended upon siloxane bridge (Si-O-Si) formation between the silica surface and the silane molecule, rather than on intermolecular bonding between adjacent silane molecules. Pre-silanization decontamination based upon boiling silica in 0.05-5% sodium peroxodisulfate, followed by ultrasonic rinsing in acetone, most effectively decontaminated filler. Consequently, it significantly improved the bonding of silane molecules to silanol groups at the silica surface. Experimental composites produced following pre-silanization decontamination of filler revealed a diametral tensile strength that was resistant to degradation by thermocycling.

Composite Resins↗

PubMed2002

The mature form of adrenomedullin correlates with brain natriuretic peptide in plasma of chronic hemodialysis patients.

AIM: Adrenomedullin (AM), a hypotensive and natriuretic peptide, consists of an amidated mature form (mAM) and an intermediate form in human plasma, of which only mAM exerts biological activity. Like atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), plasma levels of mAM are reported to be significantly elevated in hemodialysis (HD) patients, suggesting that mAM may be stimulated partly by increased body fluid volume in a manner similar to the natriuretic peptides. Here, we examined the relationship between mAM levels and ANP or BNP levels and the effect of HD on plasma mAM in HD patients. PATIENTS AND METHODS: We measured plasma levels of mAM, total AM (tAM), ANP and BNP before and after HD in patients on long-term HD (n = 22, mean age 56.3 +/- 3.2 years) using radioimmunoassay. RESULTS: Baseline mAM (2.7 +/- 0.3 fmol/ml) and tAM (23.6 +/- 2.0 fmol/ml) were significantly higher in HD patients than in healthy subjects (1.1 +/- 0.2 fmol/ml, 9.0 +/- 2.1 fmol/ml, respectively). HD significantly reduced the levels to 1.2 +/- 0.2 fmol/ml and 13.8 +/- 1.4 fmol/ml, respectively, although tAM levels were still elevated compared to healthy subjects. Similar plasma ANP and BNP levels were obtained in HD patients. There were significant correlations between mAM and tAM levels before and after HD and between HD-induced changes in mAM and tAM levels. In the pre-HD state, levels of both mAM and tAM correlated significantly with BNP levels, but the correlation of BNP with mAM was closer than that with tAM. In contrast, no correlations were observed between the 2 forms of AM and ANP. Changes in mAM levels during HD also correlated significantly with BNP but not ANP levels, although the changes in tAM did not correlate with those of the 2 natriuretic peptides. CONCLUSION: Our results suggest that the secretion/metabolism of mAM may be regulated in a manner similar to that of BNP in HD patients.

Adrenomedullin↗

PubMed2001

Glutamic acid decarboxylase-immunoreactivity of bulbar respiratory neurons identified by intracellular recording and labeling in rats.

To distinguish the GABAergic neuron in the ventral respiratory group (VRG) of rats, immunohistochemical staining of glutamic acid decarboxylase (GAD) was performed in neurons that had been individually identified by in vivo intracellular recording and labeling with neurobiotin. A total of five types of respiratory neurons were identified and labeled; augmenting inspiratory (aug-I, n=12), decrementing or early inspiratory (early-I, n=3), inspiration-expiration phase spanning or late inspiratory (late-I, n=3), decrementing expiratory or postinspiratory (PI, n=8), and augmenting or stage 2 expiratory (E2, n=3). In addition, expiration-inspiration phase-spanning or pre-inspiratory neurons (pre-I, n=2) were recorded, but not labeled. The membrane potential trajectory of each neuron type resembled that previously described in cat, suggesting a comparable neuronal organization between the two species. According to the axonal arborization, those labeled neurons were further classified as propriobulbar (6 aug-I, all early-I, all late-I, and 3 PI), bulbospinal (2 aug-I and all E2) and cranial-motor neurons (4 aug-I and 5 PI). GAD-immunoreactivity was consistently detected in the propriobulbar neurons, while it was not seen in cranial-motor and bulbospinal neurons. In addition, GAD-immunoreactive varicosities were found surrounding the somatic and dendritic surface of all labeled neurons. The present results illustrate that the propriobulbar types of early-I, aug-I, late-I and PI neurons are GABAergic inhibitory neurons and virtually all types of respiratory neurons receive GABAergic inputs in the rat's VRG.

Action Potentials↗

PubMed2001

Dynamics of postprandial remnant-like lipoprotein particles in serum after loading of diacylglycerols.

BACKGROUND: To compare the effects of diacylglycerol (DAG) on postprandial lipid metabolism with triacylglycerol (TAG), we examined the differences in the dynamics of remnant lipoproteins after loading of DAG or TAG of the same fatty acid composition. METHODS: The subjects were comprised of 6 male volunteers who orally took creamed test meals prepared with either DAG or TAG at a dose of 30 g lipid/m(2) of body surface area in the early morning after fasting for at least 12 h. Blood was taken before and 2, 3, 4, 6 and 8 h after lipid loading. To quantify the amount of remnants, as the parameters, we used concentrations of cholesterol (RLP-C) and triacylglycerol (RLP-TG) in remnant-like lipoprotein particles (RLP) of serum. RESULTS: The serum triacylglycerol concentration was markedly increased 2 h after loading of DAG and TAG. Serum triacylglycerol concentrations at 2, 3 and 8 h after loading of DAG were significantly lower than those after loading of TAG. The serum RLP-C concentration was significantly lower 2, 3 and 8 h after loading of DAG than TAG. There was a trend toward less increase in the RLP-TAG in the DAG group. The area under the curve (AUC) of serum RLP-TAG after DAG loading was significantly lower than that following TAG loading. CONCLUSIONS: DAG might reduce the risk of coronary arteriosclerotic diseases by weakening the postprandial increase of RLP that is known to be closely correlated with atherosclerosis.

Adult↗

PubMed2001

Cholesteryl ester transfer protein deficiency causes slow egg embryonation of Schistosoma japonicum.

In our attempt to discover a potential cause for accumulation of cholesteryl ester transfer protein (CETP) deficiency in Eastern Asia, we studied the association of CETP deficiency with pathogenesis of Schistosoma japonicum, a life-threatening parasite peculiar to this region. The eggs of S. japonicum showed slow embryonation when cultured in CETP-deficient human plasma. Restoration of CETP to the deficient plasma rescued it, while inhibition of CETP in normal plasma did not cause slow embryonation of the cultured eggs. The egg embryonation was also retarded in the liver but not in the intestine of wild-type mice in comparison to the CETP-transgenic mice. The granulomatous lesion around the parasite eggs in the liver was less in the wild-type than in the CETP-transgenic mice. Thus, CETP deficiency may act against Schistosomiasis japonica by retarding egg embryonation, a potential cause of liver granulomatosis. It does not seem directly due to the lack of CETP activity in plasma but to abnormal lipoprotein generated by chronic CETP deficiency.

Animals↗

PubMed2001

Overexpression of lipoprotein lipase in transgenic rabbits inhibits diet-induced hypercholesterolemia and atherosclerosis.

Lipoprotein lipase (LPL) is a key enzyme in the hydrolysis of TG-rich lipoproteins. To elucidate the physiological roles of LPL in lipid and lipoprotein metabolism, we generated transgenic rabbits expressing human LPL. In postheparinized plasma of transgenic rabbits, the human LPL protein levels were about 650 ng/ml, and LPL enzymatic activity was found at levels up to 4-fold greater than that in nontransgenic littermates. Increased LPL activity in transgenic rabbits was associated with as much as an 80% decrease in plasma triglycerides and a 59% decrease in high density lipoprotein-cholesterol. Analysis of the lipoprotein density fractions revealed that increased expression of the LPL transgene resulted in a remarkable reduction in the level of very low density lipoproteins as well as in the level of intermediate density lipoproteins. In addition, LDL cholesterol levels in transgenic rabbits were significantly increased. When transgenic rabbits were fed a cholesterol-rich diet, the development of hypercholesterolemia and aortic atherosclerosis was dramatically suppressed in transgenic rabbits. These results demonstrate that systemically increased LPL activity functions in the metabolism of all classes of lipoproteins, thereby playing a crucial role in plasma triglyceride hydrolysis and lipoprotein conversion, and that overexpression of LPL protects against diet-induced hypercholesterolemia and atherosclerosis.

Animals↗

PubMed2001

Analysis of Tag1-like elements in Arabidopsis thaliana and their distribution in other plants.

Analysis of genomic DNA of Arabidopsis Columbia (Col.) ecotype using a transposon Tag1-specific primer showed the presence of Tag1 homologues which was confirmed by Southern hybridization with a Tag1 probe. Further analysis showed that the homologue, 0.75 kb in length, had inverted repeats at both ends, 8-bp duplicated sequences at the site at which it is located and about 80% homology with Tag1, and was randomly distributed in the Arabidopsis genome. Based on these results, we concluded that these elements are non-autonomous variants of Tag1 and we termed this element sTag1. Using the polymerase chain reaction fragment hybridization technique, we found the distribution of such homologues in other plant species.

Arabidopsis↗

PubMed2001

The relationship between leachability of polymerization initiator and degree of conversion of visible light-cured resin.

Recently, polymerization-initiator-induced radicals have been identified as a biohazard as well as residual monomers. The present investigation was conducted to clarify the leaching behavior of the polymerization initiator and to measure the relationship between the leached amount of polymerization initiator and the degree of conversion of visible light (VL)-cured resin. Moreover, determining a suitable ratio of polymerization initiator to the base monomer according to the above relationship was carried out. The base monomer (UDMA/TEGDMA) was activated with varying concentrations of polymerization initiator (CQ/DMPT, CQ/DMAEMA) from 0.3-0.9 wt%, respectively, which were exposed to light for 40 s. Gas chromatograph mass spectrometry (GCMS) was carried out to evaluate the leached amount of polymerization initiator. The degree of conversion (DC) of the cured sample was estimated using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. As the result, it was recognized that the leachability of the polymerization initiator (CQ, DMPT, and DMAEMA) depended on the degree of conversion of the VL-cured resin. Therefore, the optimal concentration of polymerization initiator can be determined from the relation between the degree of conversion and the leached amount of polymerization initiator, which is about 0.6 wt% for CQ/DMPT (1:1 in weight) and 0.5 wt% for CQ/DMAEMA (1:1 in weight) relative to the UDMA/TEGDMA (1:1 in weight) monomer.

Dental Cements↗

PubMed2001

Assessment of cardiovascular autonomic dysfunction in multiple system atrophy.

Because heart rate is controlled mainly by the autonomic nervous system, cardiovascular autonomic dysfunction may contribute to the prognosis of patients with multiple system atrophy (MSA). To clarify cardiovascular autonomic dysfunctions in MSA, the authors investigated the relation between blood pressure (BP) and pulse rate (PR), and assessed a power spectral analysis of heart rate variability (HRV) during the clinical course using ambulatory BP and a heart rate monitor for 24 hours. The authors studied seven patients with MSA (five men and two women, aged 61.0 +/- 5.8 years) and seven healthy volunteers (four men and three women, aged 58.0 +/- 6.6 years) without hypertension, heart disease, or intracranial lesions. The MSA group showed abnormal circadian variations of BP and PR and a significantly decreased correlation coefficient between BP and PR. A significant decrease and altered circadian variation also existed in the number of changes in successive R-R intervals greater than 50 msec (RR50) and in the power of the high- and low-frequency component of HRV. The authors observed a significant negative correlation between the duration of illness and the number of changes in successive R-R intervals greater than 50 msec. The characteristic dysautonomia in MSA was a decrease in sympathetic and parasympathetic activity, with an abnormal circadian rhythm of BP and HRV. The balance between sympathetic and parasympathetic activity was also impaired. The parasympathetic modulation represented by RR50 worsened according to the development of the illness. Those autonomic dysfunctions may have affected the cardiovascular systems, which may indicate a poor prognosis in patients with MSA. An analysis of HRV and the circadian rhythm of BP and HRV are useful in evaluating cardiac autonomic dysfunctions in MSA.

Aged↗