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Kyozo Ishikawa - One of the best experts on this subject based on the ideXlab platform.
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thallium 201 single photon emission computed tomography spect in patients with duchenne s Progressive Muscular Dystrophy a histopathologic correlation study
Japanese Circulation Journal-english Edition, 2001Co-Authors: Toru Nishimura, Tadayuki Ishihara, Atsuo Yanagisawa, Hitomi Sakata, Konomi Sakata, Katsuya Shimoyama, Hideaki Yoshino, Kyozo IshikawaAbstract:The pathomorphologic mechanism responsible for abnormal perfusion imaging during thallium-201 myocardial single photon emission computed tomography (201Tl-SPECT) in patients with Duchenne's Progressive Muscular Dystrophy (DMD) was investigated. Hearts from 7 patients with DMD were evaluated histopathologically at autopsy and the results correlated with findings on initial and delayed resting 201Tl-SPECT images. The location of segments with perfusion defects correlated with the histopathologically abnormal segments in the hearts. Both the extent and degree of myocardial fibrosis were severe, especially in the posterolateral segment of the left ventricle. Severe transmural fibrosis and severe fatty infiltration were common in segments with perfusion defects. In areas of redistribution, the degree of fibrosis appeared to be greater than in areas of normal perfusion; and interMuscular edema was prominent. Thus, the degree and extent of perfusion defects detected by 201Tl-SPECT were compatible with the histopathology. The presence of the redistribution phenomenon may indicate ongoing fibrosis. Initial and delayed resting 201Tl-SPECT images can predict the site and progress of myocardial degeneration in patients with DMD.
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nine year follow up study of heart rate variability in patients with duchenne type Progressive Muscular Dystrophy
American Heart Journal, 1998Co-Authors: Masayuki Yotsukura, Tadayuki Ishihara, Konomi Sakata, Keita Fujii, Atsuo Katayama, Yasuhide Tomono, Hiromi Ando, Kyozo IshikawaAbstract:Abstract Objectives The purpose of this study was to investigate the progression of autonomic dysfunction in patients with Duchenne-type Progressive Muscular Dystrophy (DMD) over time by using heart rate variability. Background Although previous studies suggest the presence of autonomic dysfunction in patients with DMD, the precise cause is not known. On the other hand, it is well known that analysis of heart rate variability provides a useful, noninvasive means of quantifying autonomic activity. High frequency power is determined predominantly by the parasympathetic nervous system, whereas low frequency power is determined by both the parasympathetic and sympathetic nervous systems. Methods and Results Frequency and time domain analyses of heart rate variability during ambulatory electrocardiographic monitoring were performed in 17 patients with DMD over a 9-year period. At the time of entry, the mean patient age was 11 years and the mean Swinyard-Deaver stage was 4. In the first year, high frequency power was significantly lower and the ratio of low frequency to high frequency was significantly higher in patients with DMD than in the normal control subjects. These differences became significantly greater as the disease progressed. At the time of entry, low and high frequency powers increased at night in both groups. However, over time, high and low frequency powers at night tended to decrease. All of the time domain parameters were significantly lower in the patients with DMD at all time points compared with the normal control subjects. Conclusions We concluded that DMD patients have either a decrease in parasympathetic activity, an increase in sympathetic activity, or both as their disease progresses. (Am Heart J 1998;136:289-96.)
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cardiac involvement in Progressive Muscular Dystrophy of the duchenne type
Japanese Heart Journal, 1997Co-Authors: Kyozo IshikawaAbstract:Duchenne's Progressive Muscular Dystrophy (DMD) is a genetic muscle disorder that causes degeneration and atrophy of the systemic and cardiac muscle. The disease is manifested early in childhood, and most of patients die by age 20 years of respiratory failure or heart failure. The cardiac involvement in DMD is characterized pathologically by degeneration and fibrosis of the myocardium, centering around the posterolateral wall of the left ventricle. Functionally, an abnormal electrocardiogram, valve motion, wall thickness, and wall motion are observed. Furthermore, abnormalities in plasma levels of atrial natriuretic peptide and autonomic function are also demonstrated. In this review, the cardiac involvements in DMD in the following aspects are described: 1) Electrocardiogram; a) high-frequency notches on the QRS complexes, b) amplitude of QRS complexes, c) late potential, d) arrhythmias, e) heart rate variability, f) a 10-year follow-up study, 2) Echocardiographic findings, 3) Hemodynamic findings, 4) Atrial natriuretic peptide.
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circadian rhythm and variability of heart rate in duchenne type Progressive Muscular Dystrophy
American Journal of Cardiology, 1995Co-Authors: Masayuki Yotsukura, Tadayuki Ishihara, Kazuya Sasaki, Eisei Kachi, Akira Sasaki, Kyozo IshikawaAbstract:Using 24-hour Holter monitoring and time domain and power spectral measurements, we evaluated the variability of the heart rate and its circadian rhythm in 55 male patients with Duchenne-type Progressive Muscular Dystrophy (DMD) to characterize their autonomic function versus findings in 20 normal controls. Comparisons were also made in patients with mild, moderate, and severe stages of DMD. The percent difference between successive RR intervals that exceeded 50 ms, a measure of parasympathetic tone, was significantly lower even in patients with early stage of DMD than in controls (p < 0.01). This trend became marked with disease progression. Power in the high-frequency (HF) range (0.15 to 0.40 Hz), a measure of parasympathetic tone, was lower (p < 0.01), and the ratio of the power in the low-frequency (LF) range (0.04 to 0.15 Hz) and that of HF range (LF/HF ratio), a measure of sympathetic tone, was higher in DMD patients versus controls (p < 0.01). This trend was also marked with disease progression. Patients with mild or moderate disease had a slight circadian alteration in HF and LF/HF ratio. Patients with severe disease had virtually no circadian rhythm in HF. Their LF/HF ratio was higher at night (p < 0.01), lower in the morning (p < 0.01), and still lower during the day (p < 0.01), the opposite of control findings. The autonomic abnormalities in DMD were thus characterized by a significant increase in sympathetic activity and a significant decrease in parasympathetic activity. Thus, heart rate variability and circadian rhythm were useful in assessing autonomic dysfunction in DMD.
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late potentials in Progressive Muscular Dystrophy of the duchenne type
American Heart Journal, 1991Co-Authors: Masayuki Yotsukura, Taichi Ishizuka, Takashi Shimada, Kyozo IshikawaAbstract:Abstract This study describes the late potentials (LPs) obtained by signal-averaged electrocardiography (SAECG) in 66 patients with Duchenne's Progressive Muscular Dystrophy (DMD). It also assesses the possible relationships between LPs and the severity of DMD, and the findings of two-dimensional echocardiography, as well as ventricular arrhythmias examined with the Holter system. SAECGs were performed with a Marquette MAC-1 unit. Based on Swinyard-Deaver's system of stages, ranging from the mildest, S1, to the most severe, S8, one patient each could be assigned to S2 and S4, 6 to S5, 20 to S6, 21 to S7, and 17 to S8. LPs were observed in 21 of the 66 patients (32%), including 3 of the 20 assigned to S6 (15%), 10 of the 21 in S7 (48%), and 8 of the 17 in S8 (47%). The total wall motion index evaluated by the method of Hegar was significantly greater in the patients with LPs (8.4 ± 4.4) than in those without LPs (5.8 ± 3.1) ( p p p
Wilhelm Bloch - One of the best experts on this subject based on the ideXlab platform.
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integrin linked kinase stabilizes myotendinous junctions and protects muscle from stress induced damage
Journal of Cell Biology, 2008Co-Authors: Hao Ven Wang, Sara A Wickstrom, Ling Wei Chang, Klara Brixius, Eloi Montanez, Ingo Thievessen, Martin Schwander, Ulrich Muller, Wilhelm BlochAbstract:Skeletal muscle expresses high levels of integrin-linked kinase (ILK), predominantly at myotendinous junctions (MTJs) and costameres. ILK binds the cytoplasmic domain of β1 integrin and mediates phosphorylation of protein kinase B (PKB)/Akt, which in turn plays a central role during skeletal muscle regeneration. We show that mice with a skeletal muscle–restricted deletion of ILK develop a mild Progressive Muscular Dystrophy mainly restricted to the MTJs with detachment of basement membranes and accumulation of extracellular matrix. Endurance exercise training enhances the defects at MTJs, leads to disturbed subsarcolemmal myofiber architecture, and abrogates phosphorylation of Ser473 as well as phosphorylation of Thr308 of PKB/Akt. The reduction in PKB/Akt activation is accompanied by an impaired insulin-like growth factor 1 receptor (IGF-1R) activation. Coimmunoprecipitation experiments reveal that the β1 integrin subunit is associated with the IGF-1R in muscle cells. Our data identify the β1 integrin–ILK complex as an important component of IGF-1R/insulin receptor substrate signaling to PKB/Akt during mechanical stress in skeletal muscle.
Ling Wei Chang - One of the best experts on this subject based on the ideXlab platform.
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integrin linked kinase stabilizes myotendinous junctions and protects muscle from stress induced damage
Journal of Cell Biology, 2008Co-Authors: Hao Ven Wang, Sara A Wickstrom, Ling Wei Chang, Klara Brixius, Eloi Montanez, Ingo Thievessen, Martin Schwander, Ulrich Muller, Wilhelm BlochAbstract:Skeletal muscle expresses high levels of integrin-linked kinase (ILK), predominantly at myotendinous junctions (MTJs) and costameres. ILK binds the cytoplasmic domain of β1 integrin and mediates phosphorylation of protein kinase B (PKB)/Akt, which in turn plays a central role during skeletal muscle regeneration. We show that mice with a skeletal muscle–restricted deletion of ILK develop a mild Progressive Muscular Dystrophy mainly restricted to the MTJs with detachment of basement membranes and accumulation of extracellular matrix. Endurance exercise training enhances the defects at MTJs, leads to disturbed subsarcolemmal myofiber architecture, and abrogates phosphorylation of Ser473 as well as phosphorylation of Thr308 of PKB/Akt. The reduction in PKB/Akt activation is accompanied by an impaired insulin-like growth factor 1 receptor (IGF-1R) activation. Coimmunoprecipitation experiments reveal that the β1 integrin subunit is associated with the IGF-1R in muscle cells. Our data identify the β1 integrin–ILK complex as an important component of IGF-1R/insulin receptor substrate signaling to PKB/Akt during mechanical stress in skeletal muscle.
Masayuki Yotsukura - One of the best experts on this subject based on the ideXlab platform.
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nine year follow up study of heart rate variability in patients with duchenne type Progressive Muscular Dystrophy
American Heart Journal, 1998Co-Authors: Masayuki Yotsukura, Tadayuki Ishihara, Konomi Sakata, Keita Fujii, Atsuo Katayama, Yasuhide Tomono, Hiromi Ando, Kyozo IshikawaAbstract:Abstract Objectives The purpose of this study was to investigate the progression of autonomic dysfunction in patients with Duchenne-type Progressive Muscular Dystrophy (DMD) over time by using heart rate variability. Background Although previous studies suggest the presence of autonomic dysfunction in patients with DMD, the precise cause is not known. On the other hand, it is well known that analysis of heart rate variability provides a useful, noninvasive means of quantifying autonomic activity. High frequency power is determined predominantly by the parasympathetic nervous system, whereas low frequency power is determined by both the parasympathetic and sympathetic nervous systems. Methods and Results Frequency and time domain analyses of heart rate variability during ambulatory electrocardiographic monitoring were performed in 17 patients with DMD over a 9-year period. At the time of entry, the mean patient age was 11 years and the mean Swinyard-Deaver stage was 4. In the first year, high frequency power was significantly lower and the ratio of low frequency to high frequency was significantly higher in patients with DMD than in the normal control subjects. These differences became significantly greater as the disease progressed. At the time of entry, low and high frequency powers increased at night in both groups. However, over time, high and low frequency powers at night tended to decrease. All of the time domain parameters were significantly lower in the patients with DMD at all time points compared with the normal control subjects. Conclusions We concluded that DMD patients have either a decrease in parasympathetic activity, an increase in sympathetic activity, or both as their disease progresses. (Am Heart J 1998;136:289-96.)
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circadian rhythm and variability of heart rate in duchenne type Progressive Muscular Dystrophy
American Journal of Cardiology, 1995Co-Authors: Masayuki Yotsukura, Tadayuki Ishihara, Kazuya Sasaki, Eisei Kachi, Akira Sasaki, Kyozo IshikawaAbstract:Using 24-hour Holter monitoring and time domain and power spectral measurements, we evaluated the variability of the heart rate and its circadian rhythm in 55 male patients with Duchenne-type Progressive Muscular Dystrophy (DMD) to characterize their autonomic function versus findings in 20 normal controls. Comparisons were also made in patients with mild, moderate, and severe stages of DMD. The percent difference between successive RR intervals that exceeded 50 ms, a measure of parasympathetic tone, was significantly lower even in patients with early stage of DMD than in controls (p < 0.01). This trend became marked with disease progression. Power in the high-frequency (HF) range (0.15 to 0.40 Hz), a measure of parasympathetic tone, was lower (p < 0.01), and the ratio of the power in the low-frequency (LF) range (0.04 to 0.15 Hz) and that of HF range (LF/HF ratio), a measure of sympathetic tone, was higher in DMD patients versus controls (p < 0.01). This trend was also marked with disease progression. Patients with mild or moderate disease had a slight circadian alteration in HF and LF/HF ratio. Patients with severe disease had virtually no circadian rhythm in HF. Their LF/HF ratio was higher at night (p < 0.01), lower in the morning (p < 0.01), and still lower during the day (p < 0.01), the opposite of control findings. The autonomic abnormalities in DMD were thus characterized by a significant increase in sympathetic activity and a significant decrease in parasympathetic activity. Thus, heart rate variability and circadian rhythm were useful in assessing autonomic dysfunction in DMD.
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late potentials in Progressive Muscular Dystrophy of the duchenne type
American Heart Journal, 1991Co-Authors: Masayuki Yotsukura, Taichi Ishizuka, Takashi Shimada, Kyozo IshikawaAbstract:Abstract This study describes the late potentials (LPs) obtained by signal-averaged electrocardiography (SAECG) in 66 patients with Duchenne's Progressive Muscular Dystrophy (DMD). It also assesses the possible relationships between LPs and the severity of DMD, and the findings of two-dimensional echocardiography, as well as ventricular arrhythmias examined with the Holter system. SAECGs were performed with a Marquette MAC-1 unit. Based on Swinyard-Deaver's system of stages, ranging from the mildest, S1, to the most severe, S8, one patient each could be assigned to S2 and S4, 6 to S5, 20 to S6, 21 to S7, and 17 to S8. LPs were observed in 21 of the 66 patients (32%), including 3 of the 20 assigned to S6 (15%), 10 of the 21 in S7 (48%), and 8 of the 17 in S8 (47%). The total wall motion index evaluated by the method of Hegar was significantly greater in the patients with LPs (8.4 ± 4.4) than in those without LPs (5.8 ± 3.1) ( p p p
Sergey N. Illarioshkin - One of the best experts on this subject based on the ideXlab platform.
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refined genetic location of the chromosome 2p linked Progressive Muscular Dystrophy gene
Genomics, 1997Co-Authors: Sergey N. Illarioshkin, Irina A Ivanovasmolenskaya, Vsevolod V Poleshchuk, E D Markova, Hajime Tanaka, Shoji TsujiAbstract:Autosomal recessive Progressive Muscular dystrophies may be clinically subclassified into limb-girdle Muscular Dystrophy (LGMD) and distal myopathy (DM), each clinical form being genetically heterogeneous. Genes for LGMD type 2B and Miyoshi myopathy (a form of DM) have been mapped to essentially the same region on chromosome 2p. We described recently a large inbred family with autosomal recessive Muscular Dystrophy in which the LGMD and the DM phenotypes were manifested in separate affected members, and we assigned the gene for this condition to the same locus as in LGMD2B and Miyoshi myopathy. Here we report extended haplotypes in this family generated from 15 markers located at the region of interest on chromosome 2p13. Key recombinants allowed us to reduce further the candidate region for this polymorphic condition and defined the loci D2S327 and D2S2111 as the most likely boundaries of the mutant gene.
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Clinical and molecular analysis of a large family with three distinct phenotypes of Progressive Muscular Dystrophy.
Brain : a journal of neurology, 1996Co-Authors: Sergey N. Illarioshkin, Vsevolod V Poleshchuk, E D Markova, Hajime Tanaka, I A Ivanova-smolenskaya, N V Vereshchagin, S M Lozhnikova, V S Sukhorukov, S A Limborska, P A SlominskyAbstract:We describe a unique six-generation, highly consanguineous family originating from an isolated mountainous village in the Russian province of Daghestan. Three separate clinical phenotypes of Progressive Muscular Dystrophy were identified in this large family. Seven patients developed a classical limb-girdle variant of Muscular Dystrophy (LGMD), with disease onset at 15-30 years and loss of ambulation within a 25-year course. The second group included three patients with a slowly Progressive distal myopathy first manifested in the late teens and confined to the tibial and calf muscles. Each of these two phenotypes segregated independently as an autosomal recessive trait, and muscle biopsies showed non-specific myopathic changes. Lastly, two male siblings exhibited an atypical variant of Duchenne Muscular Dystrophy confirmed by detection of a deletion in the dystrophin gene. To clarify the molecular basis of the polymorphic autosomal recessive form of Muscular Dystrophy in this kindred, we performed molecular genetic studies on 67 family members and obtained significant evidence for linkage to chromosome 2p. A maximum pairwise lod (logarithm of odds) score of 5.64 was achieved at the zero recombination fraction (i.e. at theta = 0.00) for locus D2S291; multipoint linkage analysis confirmed the most likely location of a mutant gene near D2S291. The patients with LGMD and those with the distal Muscular Dystrophy phenotype share a common affected homozygous haplotype associated with the same founder chromosome; key recombinants defined D2S286 and D2S292 to be the closest loci flanking the mutant gene. Remarkably, two clinically distinct forms of autosomal recessive Muscular Dystrophy, LGMD type 2B (LGMD2B) and Miyoshi myopathy, were recently mapped to the same locus. We suggest that all three chromosome 2p-linked conditions may represent allelic disorders, i.e. different phenotypic expressions of a single gene.
