Dystrophin quantification and clinical correlations in Becker muscular dystrophy: implications for clinical trials.

Science.gov (United States)

Anthony, Karen; Cirak, Sebahattin; Torelli, Silvia; Tasca, Giorgio; Feng, Lucy; Arechavala-Gomeza, Virginia; Armaroli, Annarita; Guglieri, Michela; Straathof, Chiara S; Verschuuren, Jan J; Aartsma-Rus, Annemieke; Helderman-van den Enden, Paula; Bushby, Katherine; Straub, Volker; Sewry, Caroline; Ferlini, Alessandra; Ricci, Enzo; Morgan, Jennifer E; Muntoni, Francesco

2011-12-01

Duchenne muscular dystrophy is caused by mutations in the DMD gene that disrupt the open reading frame and prevent the full translation of its protein product, dystrophin. Restoration of the open reading frame and dystrophin production can be achieved by exon skipping using antisense oligonucleotides targeted to splicing elements. This approach aims to transform the Duchenne muscular dystrophy phenotype to that of the milder disorder, Becker muscular dystrophy, typically caused by in-frame dystrophin deletions that allow the production of an internally deleted but partially functional dystrophin. There is ongoing debate regarding the functional properties of the different internally deleted dystrophins produced by exon skipping for different mutations; more insight would be valuable to improve and better predict the outcome of exon skipping clinical trials. To this end, we have characterized the clinical phenotype of 17 patients with Becker muscular dystrophy harbouring in-frame deletions relevant to on-going or planned exon skipping clinical trials for Duchenne muscular dystrophy and correlated it to the levels of dystrophin, and dystrophin-associated protein expression. The cohort of 17 patients, selected exclusively on the basis of their genotype, included 4 asymptomatic, 12 mild and 1 severe patient. All patients had dystrophin levels of >40% of control and significantly higher dystrophin (P = 0.013), β-dystroglycan (P = 0.025) and neuronal nitric oxide synthase (P = 0.034) expression was observed in asymptomatic individuals versus symptomatic patients with Becker muscular dystrophy. Furthermore, grouping the patients by deletion, patients with Becker muscular dystrophy with deletions with an end-point of exon 51 (the skipping of which could rescue the largest group of Duchenne muscular dystrophy deletions) showed significantly higher dystrophin levels (P = 0.034) than those with deletions ending with exon 53. This is the first quantitative study on both

Utrophin Compensates dystrophin Loss during Mouse Spermatogenesis

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Chen, Hung-Chih; Chin, Yu-Feng; Lundy, David J.; Liang, Chung-Tiang; Chi, Ya-Hui; Kuo, Paolin; Hsieh, Patrick C. H.

2017-01-01

Duchenne muscular dystrophy (DMD) is an X-linked genetic disorder resulting from mutations in the dystrophin gene. The mdx/utrn ?/? mouse, lacking in both dystrophin and its autosomal homologue utrophin, is commonly used to model the clinical symptoms of DMD. Interestingly, these mice are infertile but the mechanisms underlying this phenomenon remain unclear. Using dystrophin deficient mdx mouse and utrophin haplodeficient mdx/utrn +/? mouse models, we demonstrate the contribution of Dp427 (f...

Ex vivo stretch reveals altered mechanical properties of isolated dystrophin-deficient hearts.

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Matthew S Barnabei

Full Text Available Duchenne muscular dystrophy (DMD is a progressive and fatal disease of muscle wasting caused by loss of the cytoskeletal protein dystrophin. In the heart, DMD results in progressive cardiomyopathy and dilation of the left ventricle through mechanisms that are not fully understood. Previous reports have shown that loss of dystrophin causes sarcolemmal instability and reduced mechanical compliance of isolated cardiac myocytes. To expand upon these findings, here we have subjected the left ventricles of dystrophin-deficient mdx hearts to mechanical stretch. Unexpectedly, isolated mdx hearts showed increased left ventricular (LV compliance compared to controls during stretch as LV volume was increased above normal end diastolic volume. During LV chamber distention, sarcomere lengths increased similarly in mdx and WT hearts despite greater excursions in volume of mdx hearts. This suggests that the mechanical properties of the intact heart cannot be modeled as a simple extrapolation of findings in single cardiac myocytes. To explain these findings, a model is proposed in which disruption of the dystrophin-glycoprotein complex perturbs cell-extracellular matrix contacts and promotes the apparent slippage of myocytes past each other during LV distension. In comparison, similar increases in LV compliance were obtained in isolated hearts from β-sarcoglycan-null and laminin-α(2 mutant mice, but not in dysferlin-null mice, suggesting that increased whole-organ compliance in mdx mice is a specific effect of disrupted cell-extracellular matrix contacts and not a general consequence of cardiomyopathy via membrane defect processes. Collectively, these findings suggest a novel and cell-death independent mechanism for the progressive pathological LV dilation that occurs in DMD.

Studying the role of dystrophin-associated proteins in influencing Becker muscular dystrophy disease severity.

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van den Bergen, J C; Wokke, B H A; Hulsker, M A; Verschuuren, J J G M; Aartsma-Rus, A M

2015-03-01

Becker muscular dystrophy is characterized by a variable disease course. Many factors have been implicated to contribute to this diversity, among which the expression of several components of the dystrophin associated glycoprotein complex. Together with dystrophin, most of these proteins anchor the muscle fiber cytoskeleton to the extracellular matrix, thus protecting the muscle from contraction induced injury, while nNOS is primarily involved in inducing vasodilation during muscle contraction, enabling adequate muscle oxygenation. In the current study, we investigated the role of three components of the dystrophin associated glycoprotein complex (beta-dystroglycan, gamma-sarcoglycan and nNOS) and the dystrophin homologue utrophin on disease severity in Becker patients. Strength measurements, data about disease course and fresh muscle biopsies of the anterior tibial muscle were obtained from 24 Becker patients aged 19 to 66. The designation of Becker muscular dystrophy in this study was based on the mutation and not on the clinical severity. Contrary to previous studies, we were unable to find a relationship between expression of nNOS, beta-dystroglycan and gamma-sarcoglycan at the sarcolemma and disease severity, as measured by muscle strength in five muscle groups and age at reaching several disease milestones. Unexpectedly, we found an inverse correlation between utrophin expression at the sarcolemma and age at reaching disease milestones. Copyright © 2015 Elsevier B.V. All rights reserved.

Characterization of a novel Dp71 dystrophin-associated protein complex (DAPC) present in the nucleus of HeLa cells: Members of the nuclear DAPC associate with the nuclear matrix

International Nuclear Information System (INIS)

Fuentes-Mera, Lizeth; Rodriguez-Munoz, Rafael; Gonzalez-Ramirez, Ricardo; Garcia-Sierra, Francisco; Gonzalez, Everardo; Mornet, Dominique; Cisneros, Bulmaro

2006-01-01

Dystrophin is an essential component in the assembly and maintenance of the dystrophin-associated protein complex (DAPC), which includes members of the dystroglycan, syntrophin, sarcoglycan and dystrobrevin protein families. Distinctive complexes have been described in the cell membrane of different tissues and cultured cells. In this work, we report the identification and characterization of a novel DAPC present in the nuclei of HeLa cells, which contains dystrophin Dp71 as a key component. Using confocal microscopy and cell fractionation analyses, we found the presence of Dp71, β-sarcoglycan, β-dystroglycan, α- and β-syntrophin, α1- and β-dystrobrevin and nNOS in the nuclei of HeLa cells. Furthermore, we demonstrated by co-immunoprecipitation experiments that most of these proteins form a complex in the nuclear compartment. Next, we analyze the possible association of the nuclear DAPC with the nuclear matrix. We found the presence of Dp71, β-dystroglycan, nNOS, β-sarcoglycan, α/β syntrophin, α1-dystrobrevin and β-dystrobrevin in the nuclear matrix protein fractions and in situ nuclear matrix preparations from HeLa cells. Moreover, we found that Dp71, β-dystroglycan and β-dystrobrevin co-immunoprecipitated with the nuclear matrix proteins lamin B1 and actin. The association of members of the nuclear DAPC with the nuclear matrix indicates that they may work as scaffolding proteins involved in nuclear architecture

Increased susceptibility of dystrophin-deficient brain to mild hypoxia

International Nuclear Information System (INIS)

Wallis, T.; Rae, C.; Bubb, W.A.; Head, S.I.

2002-01-01

Full text: Duchenne muscular dystrophy is an X-linked disorder resulting from total absence of the 427 kDa protein dystrophin. Dystrophin is normally expressed in the brain mainly in a neuronal subpopulation: cortical pyramidal cells, hippocampal CA1 neurons and cerebellar Purkinje cells. One suggested role for dystrophin is in colocalising mitochondrial creatine kinase with ADP translocase and ATP synthase in mitochondria. Brain tissue slices in the murine model of Duchenne dystrophy, the mdx mouse, have been shown to be more sensitive to hypoxia than control. In this work, we used 13 C NMR to monitor the metabolic response of mdx cortical brain tissue slices to normoxia (95%O 2 /5% CO 2 ) and mild hypoxia (95%air/5% CO 2 ). Under normoxic conditions, mdx cortical slices displayed increased net flux through the Krebs cycle and glutamate/glutamine cycle, consistent with the proposed GABA A lesion which results in decreased inhibitory input. By contrast, mild hypoxia resulted in a significant increase in the total pool size of lactate and decreased net flux of 13 C from [3- 13 C]pyruvate into glutamate C4, GABA C2 and Ala C2, as well as decreased anaplerotic activity as measured by the ratio of Asp C2: Asp C3 label. Mild hypoxia has a significantly greater effect on brain oxidative metabolism in mdx mice, than in control

Identification of new dystroglycan complexes in skeletal muscle.

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Eric K Johnson

Full Text Available The dystroglycan complex contains the transmembrane protein β-dystroglycan and its interacting extracellular mucin-like protein α-dystroglycan. In skeletal muscle fibers, the dystroglycan complex plays an important structural role by linking the cytoskeletal protein dystrophin to laminin in the extracellular matrix. Mutations that affect any of the proteins involved in this structural axis lead to myofiber degeneration and are associated with muscular dystrophies and congenital myopathies. Because loss of dystrophin in Duchenne muscular dystrophy (DMD leads to an almost complete loss of dystroglycan complexes at the myofiber membrane, it is generally assumed that the vast majority of dystroglycan complexes within skeletal muscle fibers interact with dystrophin. The residual dystroglycan present in dystrophin-deficient muscle is thought to be preserved by utrophin, a structural homolog of dystrophin that is up-regulated in dystrophic muscles. However, we found that dystroglycan complexes are still present at the myofiber membrane in the absence of both dystrophin and utrophin. Our data show that only a minority of dystroglycan complexes associate with dystrophin in wild type muscle. Furthermore, we provide evidence for at least three separate pools of dystroglycan complexes within myofibers that differ in composition and are differentially affected by loss of dystrophin. Our findings indicate a more complex role of dystroglycan in muscle than currently recognized and may help explain differences in disease pathology and severity among myopathies linked to mutations in DAPC members.

Targeted Exon Skipping to Address “Leaky” Mutations in the Dystrophin Gene

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Sue Fletcher

2012-01-01

Full Text Available Protein-truncating mutations in the dystrophin gene lead to the progressive muscle wasting disorder Duchenne muscular dystrophy, whereas in-frame deletions typically manifest as the milder allelic condition, Becker muscular dystrophy. Antisense oligomer-induced exon skipping can modify dystrophin gene expression so that a disease-associated dystrophin pre-mRNA is processed into a Becker muscular dystrophy-like mature transcript. Despite genomic deletions that may encompass hundreds of kilobases of the gene, some dystrophin mutations appear “leaky”, and low levels of high molecular weight, and presumably semi-functional, dystrophin are produced. A likely causative mechanism is endogenous exon skipping, and Duchenne individuals with higher baseline levels of dystrophin may respond more efficiently to the administration of splice-switching antisense oligomers. We optimized excision of exons 8 and 9 in normal human myoblasts, and evaluated several oligomers in cells from eight Duchenne muscular dystrophy patients with deletions in a known “leaky” region of the dystrophin gene. Inter-patient variation in response to antisense oligomer induced skipping in vitro appeared minimal. We describe oligomers targeting exon 8, that unequivocally increase dystrophin above baseline in vitro, and propose that patients with leaky mutations are ideally suited for participation in antisense oligomer mediated splice-switching clinical studies.

Nanopolymers improve delivery of exon skipping oligonucleotides and concomitant dystrophin expression in skeletal muscle of mdx mice

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Sirsi Shashank R

2008-04-01

Full Text Available Abstract Background Exon skipping oligonucleotides (ESOs of 2'O-Methyl (2'OMe and morpholino chemistry have been shown to restore dystrophin expression in muscle fibers from the mdx mouse, and are currently being tested in phase I clinical trials for Duchenne Muscular Dystrophy (DMD. However, ESOs remain limited in their effectiveness because of an inadequate delivery profile. Synthetic cationic copolymers of poly(ethylene imine (PEI and poly(ethylene glycol (PEG are regarded as effective agents for enhanced delivery of nucleic acids in various applications. Results We examined whether PEG-PEI copolymers can facilitate ESO-mediated dystrophin expression after intramuscular injections into tibialis anterior (TA muscles of mdx mice. We utilized a set of PEG-PEI copolymers containing 2 kDa PEI and either 550 Da or 5 kDa PEG, both of which bind 2'OMe ESOs with high affinity and form stable nanoparticulates with a relatively low surface charge. Three weekly intramuscular injections of 5 μg of ESO complexed with PEI2K-PEG550 copolymers resulted in about 500 dystrophin-positive fibers and about 12% of normal levels of dystrophin expression at 3 weeks after the initial injection, which is significantly greater than for injections of ESO alone, which are known to be almost completely ineffective. In an effort to enhance biocompatibility and cellular uptake, the PEI2K-PEG550 and PEI2K-PEG5K copolymers were functionalized by covalent conjugation with nanogold (NG or adsorbtion of colloidal gold (CG, respectively. Surprisingly, using the same injection and dosing regimen, we found no significant difference in dystrophin expression by Western blot between the NG-PEI2K-PEG550, CG-PEI2K-PEG5K, and non-functionalized PEI2K-PEG550 copolymers. Dose-response experiments using the CG-PEI2K-PEG5K copolymer with total ESO ranging from 3–60 μg yielded a maximum of about 15% dystrophin expression. Further improvements in dystrophin expression up to 20% of normal

Exon skipping and translation in patients with frameshift deletions in the dystrophin gene

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Sherratt, T.G.; Dubowitz, V.; Sewry, C.A.; Strong, P.N. (Royal Postgraduate Medical School, London (United Kingdom)); Vulliamy, T. (Hammersmith Hospital, London (United Kingdom))

1993-11-01

Although many Duchenne muscular dystrophy patients have a deletion in the dystrophin gene which disrupts the translational reading frame, they express dystrophin in a small proportion of skeletal muscle fibers ([open quotes]revertant fibers[close quotes]). Antibody studies have shown, indirectly, that dystrophin synthesis in revertant fibers is facilitated by a frame-restoring mechanism; in the present study, the feasibility of mRNA splicing was investigated. Dystrophin transcripts were analyzed in skeletal muscle from individuals possessing revertant fibers and a frameshift deletion in the dystrophin gene. In each case a minor in-frame transcript was detected, in which exons adjacent to those deleted from the genome had been skipped. There appeared to be some correlation between the levels of in-frame transcripts and the predicted translation products. Low levels of alternatively spliced transcripts were also present in normal muscle. The results provide further evidence of exon skipping in the dystrophin gene and indicate that this may be involved in the synthesis of dystrophin by revertant fibers. 44 refs., 12 figs.

Dystrophin analysis in carriers of Duchenne and Becker muscular dystrophy

NARCIS (Netherlands)

Hoogerwaard, Edo M.; Ginjaar, Ieke B.; Bakker, Egbert; de Visser, Marianne

2005-01-01

Associations between clinical phenotype (muscle weakness, dilated cardiomyopathy) and dystrophin abnormalities in muscle tissue among definite carriers of Duchenne (DMD) and Becker muscular dystrophy (BMD) were investigated. No associations between dystrophin abnormalities and clinical variables in

Adhalin, the 50 kD dystrophin associated protein, is not the locus for severe childhood autosomal recessive dystrophy (SCARMD)

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McNally, E.M.; Selig, S.; Kunkel, L.M. [Children`s Hospital, Boston, MA (United States)

1994-09-01

Mutations in the carboxyl-terminus in dystrophin are normally sufficient to produce severely dystrophic muscle. This portion of dystrophin binds a complex of dystrophin-associated glycoproteins (DAGs). The genes encoding these DAGs are candidate genes for causing neuromuscular disease. Immunoreactivity for adhalin, the 50 kD DAG, is absent in muscle biopsies from patients with SCARMD, a form of dystrophy clinically similar Duchenne muscular dystrophy. Prior linkage analysis in SCARMD families revealed that the disease gene segregates with markers on chromosome 13. To determine the molecular role that adhalin may play in SCARMD, human cDNA and genomic sequences were isolated. Primers were designed based on predicted areas of conservation in rabbit adhalin and used in RT-PCR with human skeletal and cardiac muscle. RT-PCR products were confirmed by sequence as human adhalin and then used as probes for screening human cDNA and genomic libraries. Human and rabbit adhalin are 90% identical, and among the cDNAs, a novel splice form of adhalin was seen which may encode part of the 35 kD component of the dystrophin-glycoprotein complex. To our surprise, only human/rodent hybrids containing human chromosome 17 amplified adhalin sequences in a PCR analysis. FISH analysis with three overlapping genomic sequences confirmed the chromosome 17 location and further delineated the map position to 17q21. Therefore, adhalin is excluded as the gene causing SCARMD.

Carrier detection of duchenne and becker muscular dystrophy using muscle dystrophin immunohistochemistry

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Acary S. Bulle Oliveira

1992-12-01

Full Text Available To ascertain whether dystrophin immunohistochemistry could improve DMD/ BMD carrier detection, we analyzed 14 muscle biopsies from 13 DMD and one BMD probable and possible carriers. All women were also evaluated using conventional methods, including genetic analysis, clinical and neurological evaluation, serum CK levels, KMG, and muscle biopsy. In 6 cases, there was a mosaic of dystrophin-positive and dystrophin-deficient fibers that allowed to make the diagnosis of a carrier state. Comparing dystrophin immunohistochemistry to the traditional methods, it was noted that this method is less sensitive than serum CK measuremens, but is more sensitive than EMG and muscle biopsy. The use of dystrophin immunohistochemistry in addition to CK, EMG and muscle biopsy improved the accuracy of carrier detection. This method is also helpful to distinguish manifesting DMD carriers from patients with other neuromuscular diseases like limb-girdle muscular dystrophy and spinal muscular atrophy.

Evolutionary study of vertebrate and invertebrate members of the dystrophin and utrophin gene family

Energy Technology Data Exchange (ETDEWEB)

Roberts, R.G.; Nicholson, L.; Bobrow, M. [Paediatric Research Unit, London (United Kingdom)] [and others

1994-09-01

Vertebrates express two members of the dystrophin gene family. The prototype, dystrophin, is expressed in muscle and neural tissue, and is defective in the human disorders Duchenne and Becker muscular dystrophy (DMD, BMD). The dystrophin homologue utrophin is more generally expressed but has not yet been associated with a genetic disorder. The function of neither protein is clear. A comparison of human utrophin with the known dystrophins (human, mouse, chicken, Torpedo) suggests that dystrophin and utrophin diverged before the vertebrate radiation. We have used reverse-transcript PCR (RT-PCR) directed by degenerate primers to characterize dystrophin and utrophin transcripts from a range of vertebrate and invertebrate animals. Our results suggest that the duplication leading to distinct dystrophin and utrophin genes occurred close to the point of divergence of urochordates from the cephalochordate-vertebrate lineage. This divergence may have occurred to fulfill a novel role which arose at this point, or may reflect a need for separate regulation of the neuromuscular and other functions of the ancient dystrophin. Our data include sequences of the first non-human utrophins to be characterized, and show these to be substantially more divergent than their cognate dystrophins. In addition, our results provide a large body of information regarding the tolerance of amino acid positions in the cysteine-rich and C-terminal domains to substitution. This will aid the interpretations of DMD and BMD missense mutations in these regions.

Laryngeal Muscles Are Spared in the Dystrophin Deficient "mdx" Mouse

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Thomas, Lisa B.; Joseph, Gayle L.; Adkins, Tracey D.; Andrade, Francisco H.; Stemple, Joseph C.

2008-01-01

Purpose: "Duchenne muscular dystrophy (DMD)" is caused by the loss of the cytoskeletal protein, dystrophin. The disease leads to severe and progressive skeletal muscle wasting. Interestingly, the disease spares some muscles. The purpose of the study was to determine the effects of dystrophin deficiency on 2 intrinsic laryngeal muscles, the…

Computational study of the human dystrophin repeats: interaction properties and molecular dynamics.

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Baptiste Legrand

Full Text Available Dystrophin is a large protein involved in the rare genetic disease Duchenne muscular dystrophy (DMD. It functions as a mechanical linker between the cytoskeleton and the sarcolemma, and is able to resist shear stresses during muscle activity. In all, 75% of the dystrophin molecule consists of a large central rod domain made up of 24 repeat units that share high structural homology with spectrin-like repeats. However, in the absence of any high-resolution structure of these repeats, the molecular basis of dystrophin central domain's functions has not yet been deciphered. In this context, we have performed a computational study of the whole dystrophin central rod domain based on the rational homology modeling of successive and overlapping tandem repeats and the analysis of their surface properties. Each tandem repeat has very specific surface properties that make it unique. However, the repeats share enough electrostatic-surface similarities to be grouped into four separate clusters. Molecular dynamics simulations of four representative tandem repeats reveal specific flexibility or bending properties depending on the repeat sequence. We thus suggest that the dystrophin central rod domain is constituted of seven biologically relevant sub-domains. Our results provide evidence for the role of the dystrophin central rod domain as a scaffold platform with a wide range of surface features and biophysical properties allowing it to interact with its various known partners such as proteins and membrane lipids. This new integrative view is strongly supported by the previous experimental works that investigated the isolated domains and the observed heterogeneity of the severity of dystrophin related pathologies, especially Becker muscular dystrophy.

Ex vivo gene editing of the dystrophin gene in muscle stem cells mediated by peptide nucleic acid single stranded oligodeoxynucleotides induces stable expression of dystrophin in a mouse model for Duchenne muscular dystrophy.

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Nik-Ahd, Farnoosh; Bertoni, Carmen

2014-07-01

Duchenne muscular dystrophy (DMD) is a fatal disease caused by mutations in the dystrophin gene, which result in the complete absence of dystrophin protein throughout the body. Gene correction strategies hold promise to treating DMD. Our laboratory has previously demonstrated the ability of peptide nucleic acid single-stranded oligodeoxynucleotides (PNA-ssODNs) to permanently correct single-point mutations at the genomic level. In this study, we show that PNA-ssODNs can target and correct muscle satellite cells (SCs), a population of stem cells capable of self-renewing and differentiating into muscle fibers. When transplanted into skeletal muscles, SCs transfected with correcting PNA-ssODNs were able to engraft and to restore dystrophin expression. The number of dystrophin-positive fibers was shown to significantly increase over time. Expression was confirmed to be the result of the activation of a subpopulation of SCs that had undergone repair as demonstrated by immunofluorescence analyses of engrafted muscles using antibodies specific to full-length dystrophin transcripts and by genomic DNA analysis of dystrophin-positive fibers. Furthermore, the increase in dystrophin expression detected over time resulted in a significant improvement in muscle morphology. The ability of transplanted cells to return into quiescence and to activate upon demand was confirmed in all engrafted muscles following injury. These results demonstrate the feasibility of using gene editing strategies to target and correct SCs and further establish the therapeutic potential of this approach to permanently restore dystrophin expression into muscle of DMD patients. © 2014 AlphaMed Press.

Matrix metalloproteinase-2 ablation in dystrophin-deficient mdx muscles reduces angiogenesis resulting in impaired growth of regenerated muscle fibers.

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Miyazaki, Daigo; Nakamura, Akinori; Fukushima, Kazuhiro; Yoshida, Kunihiro; Takeda, Shin'ichi; Ikeda, Shu-ichi

2011-05-01

Matrix metalloproteases (MMPs) are a family of endopeptidases classified into subgroups based on substrate preference in normal physiological processes such as embryonic development and tissue remodeling, as well as in various disease processes via degradation of extracellular matrix components. Among the MMPs, MMP-9 and MMP-2 have been reported to be up-regulated in skeletal muscles in the lethal X-linked muscle disorder Duchenne muscular dystrophy (DMD), which is caused by loss of dystrophin. A recent study showed that deletion of the MMP9 gene in mdx, a mouse model for DMD, improved skeletal muscle pathology and function; however, the role of MMP-2 in the dystrophin-deficient muscle is not well known. In this study, we aimed at verifying the role of MMP-2 in the dystrophin-deficient muscle by using mdx mice with genetic ablation of MMP-2 (mdx/MMP-2(-/-)). We found impairment of regenerated muscle fiber growth with reduction of angiogenesis in mdx/MMP-2(-/-) mice at 3 months of age. Expression of vascular endothelial growth factor-A (VEGF-A), an important angiogenesis-related factor, decreased in mdx/MMP-2(-/-) mice at 3 months of age. MMP-2 had not a critical role in the degradation of dystrophin-glycoprotein complex (DGC) components such as β-dystroglycan and β-sarcoglycan in the regeneration process of the dystrophic muscle. Accordingly, MMP-2 may be essential for growth of regenerated muscle fibers through VEGF-associated angiogenesis in the dystrophin-deficient skeletal muscle.

Functional rescue of dystrophin-deficient mdx mice by a chimeric peptide-PMO.

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Yin, Haifang; Moulton, Hong M; Betts, Corinne; Merritt, Thomas; Seow, Yiqi; Ashraf, Shirin; Wang, Qingsong; Boutilier, Jordan; Wood, Matthew Ja

2010-10-01

Splice modulation using antisense oligonucleotides (AOs) has been shown to yield targeted exon exclusion to restore the open reading frame and generate truncated but partially functional dystrophin protein. This has been successfully demonstrated in dystrophin-deficient mdx mice and in Duchenne muscular dystrophy (DMD) patients. However, DMD is a systemic disease; successful therapeutic exploitation of this approach will therefore depend on effective systemic delivery of AOs to all affected tissues. We have previously shown the potential of a muscle-specific/arginine-rich chimeric peptide-phosphorodiamidate morpholino (PMO) conjugate, but its long-term activity, optimized dosing regimen, capacity for functional correction and safety profile remain to be established. Here, we report the results of this chimeric peptide-PMO conjugate in the mdx mouse using low doses (3 and 6 mg/kg) administered via a 6 biweekly systemic intravenous injection protocol. We show 100% dystrophin-positive fibers and near complete correction of the dystrophin transcript defect in all peripheral muscle groups, with restoration of 50% dystrophin protein over 12 weeks, leading to correction of the DMD pathological phenotype and restoration of muscle function in the absence of detectable toxicity or immune response. Chimeric muscle-specific/cell-penetrating peptides therefore represent highly promising agents for systemic delivery of splice-correcting PMO oligomers for DMD therapy.

Mismatched single stranded antisense oligonucleotides can induce efficient dystrophin splice switching

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Kole Ryszard

2011-10-01

Full Text Available Abstract Background Antisense oligomer induced exon skipping aims to reduce the severity of Duchenne muscular dystrophy by redirecting splicing during pre-RNA processing such that the causative mutation is by-passed and a shorter but partially functional Becker muscular dystrophy-like dystrophin isoform is produced. Normal exons are generally targeted to restore the dystrophin reading frame however, an appreciable subset of dystrophin mutations are intra-exonic and therefore have the potential to compromise oligomer efficiency, necessitating personalised oligomer design for some patients. Although antisense oligomers are easily personalised, it remains unclear whether all patient polymorphisms within antisense oligomer target sequences will require the costly process of producing and validating patient specific compounds. Methods Here we report preclinical testing of a panel of splice switching antisense oligomers, designed to excise exon 25 from the dystrophin transcript, in normal and dystrophic patient cells. These patient cells harbour a single base insertion in exon 25 that lies within the target sequence of an oligomer shown to be effective at removing exon 25. Results It was anticipated that such a mutation would compromise oligomer binding and efficiency. However, we show that, despite the mismatch an oligomer, designed and optimised to excise exon 25 from the normal dystrophin mRNA, removes the mutated exon 25 more efficiently than the mutation-specific oligomer. Conclusion This raises the possibility that mismatched AOs could still be therapeutically applicable in some cases, negating the necessity to produce patient-specific compounds.

Analysis of Dystrophin Gene Deletions by Multiplex PCR in Moroccan Patients

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Aziza Sbiti

2002-01-01

Full Text Available Duchenne and Becker muscular dystrophy (DMD and BMD are X-linked diseases resulting from a defect in the dystrophin gene located on Xp21. DMD is the most frequent neuromuscular disease in humans (1/3500 male newborn. Deletions in the dystrophin gene represent 65% of mutations in DMD/BMD patients. We have analyzed DNA from 72 Moroccan patients with DMD/BMD using the multiplex polymerase chain reaction (PCR to screen for exon deletions within the dystrophin gene, and to estimate the frequency of these abnormalities. We found dystrophin gene deletions in 37 cases. Therefore the frequency in Moroccan DMD/BMD patients is about 51.3%. All deletions were clustered in the two known hot-spots regions, and in 81% of cases deletions were detected in the region from exon 43 to exon 52. These findings are comparable to those reported in other studies. It is important to note that in our population, we can first search for deletions of DMD gene in the most frequently deleted exons determined by this study. This may facilitate the molecular diagnosis of DMD and BMD in our country.

Dystrophin in frameshift deletion patients with Becker Muscular Dystrophy

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Gangopadhyay, S.B.; Ray, P.N.; Worton, R.G.; Sherratt, T.G.; Heckmatt, J.Z.; Dubowitz, V.; Strong, P.N.; Miller, G. (Penn State College of Medicine, Hershey, PA (United States)); Shokeir, M. (Univ. Hospital, Saskatchewan (Canada))

1992-09-01

In a previous study the authors identified 14 cases with Duchenne muscular dystrophy (DMD) or its milder variant, Becker muscular dystrophy (BMD), with a deletion of exons 3-7, a deletion that would be expected to shift the translational reading frame of the mRNA and give a severe phenotype. They have examined dystrophin and its mRNA from muscle biopsies of seven cases with either mild or intermediate phenotypes. In all cases they detected slightly lower-molecular-weight dystrophin in 12%-15% abundance relative to the normal. By sequencing amplified mRNA they have found that exon 2 is spliced to exon 8, a splice that produces a frameshifted mRNA, and have found no evidence for alternate splicing that might be involved in restoration of dystrophin mRNA reading frame in the patients with a mild phenotype. Other transcriptional and posttranscriptional mechanisms such as cryptic promoter, ribosomal frameshifting, and reinitiation are suggested that might play some role in restoring the reading frame. 34 refs., 5 figs. 1 tab.

Dual AAV Gene Therapy for Duchenne Muscular Dystrophy with a 7-kb Mini-Dystrophin Gene in the Canine Model.

Science.gov (United States)

Kodippili, Kasun; Hakim, Chady H; Pan, Xiufang; Yang, Hsiao T; Yue, Yongping; Zhang, Yadong; Shin, Jin-Hong; Yang, N Nora; Duan, Dongsheng

2018-03-01

Dual adeno-associated virus (AAV) technology was developed in 2000 to double the packaging capacity of the AAV vector. The proof of principle has been demonstrated in various mouse models. Yet, pivotal evidence is lacking in large animal models of human diseases. Here we report expression of a 7-kb canine ΔH2-R15 mini-dystrophin gene using a pair of dual AAV vectors in the canine model of Duchenne muscular dystrophy (DMD). The ΔH2-R15 minigene is by far the most potent synthetic dystrophin gene engineered for DMD gene therapy. We packaged minigene dual vectors in Y731F tyrosine-modified AAV-9 and delivered to the extensor carpi ulnaris muscle of a 12-month-old affected dog at the dose of 2 × 10 13 viral genome particles/vector/muscle. Widespread mini-dystrophin expression was observed 2 months after gene transfer. The missing dystrophin-associated glycoprotein complex was restored. Treatment also reduced muscle degeneration and fibrosis and improved myofiber size distribution. Importantly, dual AAV therapy greatly protected the muscle from eccentric contraction-induced force loss. Our data provide the first clear evidence that dual AAV therapy can be translated to a diseased large mammal. Further development of dual AAV technology may lead to effective therapies for DMD and many other diseases in human patients.

A Translational Pathway Toward a Clinical Trial Using the Second-Generation AAV Micro-Dystrophin Vector

Science.gov (United States)

2016-09-01

mune system a few weeks later. It is now clear that the gene delivery vehicle (AAV virus capsid), cargo (transgene), or the protein produced from the...Ideally, delivery of a full-length dystrophin cDNA will yield the production of a full- length dystrophin protein and the maximum pro- tection of...investigational new drug (IND) application can be filed for a gene therapy trial with systemic delivery of dystrophin? Dr. Duan: A number of IND

Consecutive analysis of mutation spectrum in the dystrophin gene of 507 Korean boys with Duchenne/Becker muscular dystrophy in a single center.

Science.gov (United States)

Cho, Anna; Seong, Moon-Woo; Lim, Byung Chan; Lee, Hwa Jeen; Byeon, Jung Hye; Kim, Seung Soo; Kim, Soo Yeon; Choi, Sun Ah; Wong, Ai-Lynn; Lee, Jeongho; Kim, Jon Soo; Ryu, Hye Won; Lee, Jin Sook; Kim, Hunmin; Hwang, Hee; Choi, Ji Eun; Kim, Ki Joong; Hwang, Young Seung; Hong, Ki Ho; Park, Seungman; Cho, Sung Im; Lee, Seung Jun; Park, Hyunwoong; Seo, Soo Hyun; Park, Sung Sup; Chae, Jong Hee

2017-05-01

Duchenne and Becker muscular dystrophies (DMD and BMD) are allelic X-linked recessive muscle diseases caused by mutations in the large and complex dystrophin gene. We analyzed the dystrophin gene in 507 Korean DMD/BMD patients by multiple ligation-dependent probe amplification and direct sequencing. Overall, 117 different deletions, 48 duplications, and 90 pathogenic sequence variations, including 30 novel variations, were identified. Deletions and duplications accounted for 65.4% and 13.3% of Korean dystrophinopathy, respectively, suggesting that the incidence of large rearrangements in dystrophin is similar among different ethnic groups. We also detected sequence variations in >100 probands. The small variations were dispersed across the whole gene, and 12.3% were nonsense mutations. Precise genetic characterization in patients with DMD/BMD is timely and important for implementing nationwide registration systems and future molecular therapeutic trials in Korea and globally. Muscle Nerve 55: 727-734, 2017. © 2016 Wiley Periodicals, Inc.

Use of epitope libraries to identify exon-specific monoclonal antibodies for characterization of altered dystrophins in muscular dystrophy

Energy Technology Data Exchange (ETDEWEB)

Nguyen thi Man; Morris, G.E. (North East Wales Inst., Clwyd (United Kingdom))

1993-06-01

The majority of mutations in Xp21-linked muscular dystrophy (MD) can be identified by PCR or Southern blotting, as deletions or duplications of groups of exons in the dystrophin gene, but it is not always possible to predict how much altered dystrophin, if any, will be produced. Use of exon-specific monoclonal antibodies (mAbs) on muscle biopsies from MD patients can, in principle, provide information on both the amount of altered dystrophin produced and, when dystrophin is present, the nature of the genetic deletion or point mutation. For this purpose, mAbs which recognize regions of dystrophin encoded by known exons and whose binding is unaffected by the absence of adjacent exons are required. To map mAbs to specific exons, random [open quotes]libraries[close quotes] of expressed dystrophin fragments were created by cloning DNAseI digestion fragments of a 4.3-kb dystrophin cDNA into a pTEX expression vector. The libraries were then used to locate the epitopes recognized by 48 mAbs to fragments of 25--60 amino acids within the 1,434-amino-acid dystrophin fragment used to produce the antibodies. This is sufficiently detailed to allow further refinement by using synthetic peptides and, in many cases, to identify the exon in the DMD (Duchenne MD) gene which encodes the epitope. To illustrate their use in dystrophin analysis, a Duchenne patient with a frameshift deletion of exons 42 and 43 makes a truncated dystrophin encoded by exons 1--41, and the authors now show that this can be detected in the sarcolemma by mAbs up to and including those specific for exon 41 epitopes but not by mAbs specific for exon 43 or later epitopes. 38 refs., 2 figs., 4 tabs.

Nonmechanical Roles of Dystrophin and Associated Proteins in Exercise, Neuromuscular Junctions, and Brains

Directory of Open Access Journals (Sweden)

Bailey Nichols

2015-07-01

Full Text Available Dystrophin-glycoprotein complex (DGC is an important structural unit in skeletal muscle that connects the cytoskeleton (f-actin of a muscle fiber to the extracellular matrix (ECM. Several muscular dystrophies, such as Duchenne muscular dystrophy, Becker muscular dystrophy, congenital muscular dystrophies (dystroglycanopathies, and limb-girdle muscular dystrophies (sarcoglycanopathies, are caused by mutations in the different DGC components. Although many early studies indicated DGC plays a crucial mechanical role in maintaining the structural integrity of skeletal muscle, recent studies identified novel roles of DGC. Beyond a mechanical role, these DGC members play important signaling roles and act as a scaffold for various signaling pathways. For example, neuronal nitric oxide synthase (nNOS, which is localized at the muscle membrane by DGC members (dystrophin and syntrophins, plays an important role in the regulation of the blood flow during exercise. DGC also plays important roles at the neuromuscular junction (NMJ and in the brain. In this review, we will focus on recently identified roles of DGC particularly in exercise and the brain.

A transcriptome-based assessment of the astrocytic dystrophin-associated complex in the developing human brain.

Science.gov (United States)

Simon, Matthew J; Murchison, Charles; Iliff, Jeffrey J

2018-02-01

Astrocytes play a critical role in regulating the interface between the cerebral vasculature and the central nervous system. Contributing to this is the astrocytic endfoot domain, a specialized structure that ensheathes the entirety of the vasculature and mediates signaling between endothelial cells, pericytes, and neurons. The astrocytic endfoot has been implicated as a critical element of the glymphatic pathway, and changes in protein expression profiles in this cellular domain are linked to Alzheimer's disease pathology. Despite this, basic physiological properties of this structure remain poorly understood including the developmental timing of its formation, and the protein components that localize there to mediate its functions. Here we use human transcriptome data from male and female subjects across several developmental stages and brain regions to characterize the gene expression profile of the dystrophin-associated complex (DAC), a known structural component of the astrocytic endfoot that supports perivascular localization of the astroglial water channel aquaporin-4. Transcriptomic profiling is also used to define genes exhibiting parallel expression profiles to DAC elements, generating a pool of candidate genes that encode gene products that may contribute to the physiological function of the perivascular astrocytic endfoot domain. We found that several genes encoding transporter proteins are transcriptionally associated with DAC genes. © 2017 Wiley Periodicals, Inc.

Dystrophin Expressing Chimeric (DEC) Human Cells Provide a Potential Therapy for Duchenne Muscular Dystrophy.

Science.gov (United States)

Siemionow, Maria; Cwykiel, Joanna; Heydemann, Ahlke; Garcia, Jesus; Marchese, Enza; Siemionow, Krzysztof; Szilagyi, Erzsebet

2018-06-01

Duchenne Muscular Dystrophy (DMD) is a progressive and lethal disease caused by mutations of the dystrophin gene. Currently no cure exists. Stem cell therapies targeting DMD are challenged by limited engraftment and rejection despite the use of immunosuppression. There is an urgent need to introduce new stem cell-based therapies that exhibit low allogenic profiles and improved cell engraftment. In this proof-of-concept study, we develop and test a new human stem cell-based approach to increase engraftment, limit rejection, and restore dystrophin expression in the mdx/scid mouse model of DMD. We introduce two Dystrophin Expressing Chimeric (DEC) cell lines created by ex vivo fusion of human myoblasts (MB) derived from two normal donors (MB N1 /MB N2 ), and normal and DMD donors (MB N /MB DMD ). The efficacy of fusion was confirmed by flow cytometry and confocal microscopy based on donor cell fluorescent labeling (PKH26/PKH67). In vitro, DEC displayed phenotype and genotype of donor parent cells, expressed dystrophin, and maintained proliferation and myogenic differentiation. In vivo, local delivery of both DEC lines (0.5 × 10 6 ) restored dystrophin expression (17.27%±8.05-MB N1 /MB N2 and 23.79%±3.82-MB N /MB DMD ) which correlated with significant improvement of muscle force, contraction and tolerance to fatigue at 90 days after DEC transplant to the gastrocnemius muscles (GM) of dystrophin-deficient mdx/scid mice. This study establishes DEC as a potential therapy for DMD and other types of muscular dystrophies.

Targeted Exon Skipping to Correct Exon Duplications in the Dystrophin Gene

Directory of Open Access Journals (Sweden)

Kane L Greer

2014-01-01

Full Text Available Duchenne muscular dystrophy is a severe muscle-wasting disease caused by mutations in the dystrophin gene that ablate functional protein expression. Although exonic deletions are the most common Duchenne muscular dystrophy lesion, duplications account for 10–15% of reported disease-causing mutations, and exon 2 is the most commonly duplicated exon. Here, we describe the in vitro evaluation of phosphorodiamidate morpholino oligomers coupled to a cell-penetrating peptide and 2′-O-methyl phosphorothioate oligonucleotides, using three distinct strategies to reframe the dystrophin transcript in patient cells carrying an exon 2 duplication. Differences in exon-skipping efficiencies in vitro were observed between oligomer analogues of the same sequence, with the phosphorodiamidate morpholino oligomer coupled to a cell-penetrating peptide proving the most effective. Differences in exon 2 excision efficiency between normal and exon 2 duplication cells, were apparent, indicating that exon context influences oligomer-induced splice switching. Skipping of a single copy of exon 2 was induced in the cells carrying an exon 2 duplication, the simplest strategy to restore the reading frame and generate a normal dystrophin transcript. In contrast, multiexon skipping of exons 2–7 to generate a Becker muscular dystrophy-like dystrophin transcript was more challenging and could only be induced efficiently with the phosphorodiamidate morpholino oligomer chemistry.

Early dystrophin loss is coincident with the transition of compensated cardiac hypertrophy to heart failure.

Directory of Open Access Journals (Sweden)

Fernanda P Prado

Full Text Available Hypertension causes cardiac hypertrophy, one of the most important risk factors for heart failure (HF. Despite the importance of cardiac hypertrophy as a risk factor for the development of HF, not all hypertrophied hearts will ultimately fail. Alterations of cytoskeletal and sarcolemma-associated proteins are considered markers cardiac remodeling during HF. Dystrophin provides mechanical stability to the plasma membrane through its interactions with the actin cytoskeleton and, indirectly, to extracellular matrix proteins. This study was undertaken to evaluate dystrophin and calpain-1 in the transition from compensated cardiac hypertrophy to HF. Wistar rats were subjected to abdominal aorta constriction and killed at 30, 60 and 90 days post surgery (dps. Cardiac function and blood pressure were evaluated. The hearts were collected and Western blotting and immunofluorescence performed for dystrophin, calpain-1, alpha-fodrin and calpastatin. Statistical analyses were performed and considered significant when p<0.05. After 90 dps, 70% of the animals showed hypertrophic hearts (HH and 30% hypertrophic+dilated hearts (HD. Systolic and diastolic functions were preserved at 30 and 60 dps, however, decreased in the HD group. Blood pressure, cardiomyocyte diameter and collagen content were increased at all time points. Dystrophin expression was lightly increased at 30 and 60 dps and HH group. HD group showed decreased expression of dystrophin and calpastatin and increased expression of calpain-1 and alpha-fodrin fragments. The first signals of dystrophin reduction were observed as early as 60 dps. In conclusion, some hearts present a distinct molecular pattern at an early stage of the disease; this pattern could provide an opportunity to identify these failure-prone hearts during the development of the cardiac disease. We showed that decreased expression of dystrophin and increased expression of calpains are coincident and could work as possible

Screening of point mutations by multiple SSCP analysis in the dystrophin gene

Energy Technology Data Exchange (ETDEWEB)

Lasa, A.; Baiget, M.; Gallano, P. [Hospital Sant Pau, Barcelona (Spain)

1994-09-01

Duchenne muscular dystrophy (DMD) is a lethal, X-linked neuromuscular disorder. The population frequency of DMD is one in approximately 3500 boys, of which one third is thought to be a new mutant. The DMD gene is the largest known to date, spanning over 2,3 Mb in band Xp21.2; 79 exons are transcribed into a 14 Kb mRNA coding for a protein of 427 kD which has been named dystrophin. It has been shown that about 65% of affected boys have a gene deletion with a wide variation in localization and size. The remaining affected individuals who have no detectable deletions or duplications would probably carry more subtle mutations that are difficult to detect. These mutations occur in several different exons and seem to be unique to single patients. Their identification represents a formidable goal because of the large size and complexity of the dystrophin gene. SSCP is a very efficient method for the detection of point mutations if the parameters that affect the separation of the strands are optimized for a particular DNA fragment. The multiple SSCP allows the simultaneous study of several exons, and implies the use of different conditions because no single set of conditions will be optimal for all fragments. Seventy-eight DMD patients with no deletion or duplication in the dystrophin gene were selected for the multiple SSCP analysis. Genomic DNA from these patients was amplified using the primers described for the diagnosis procedure (muscle promoter and exons 3, 8, 12, 16, 17, 19, 32, 45, 48 and 51). We have observed different mobility shifts in bands corresponding to exons 8, 12, 43 and 51. In exons 17 and 45, altered electrophoretic patterns were found in different samples identifying polymorphisms already described.

Heteroduplex analysis of the dystrophin gene: Application to point mutation and carrier detection

Energy Technology Data Exchange (ETDEWEB)

Prior, T.W.; Papp, A.C.; Snyder, P.J.; Sedra, M.S.; Western, L.M.; Bartolo, C.; Mendell, J.R. [Ohio State Univ., Columbus, OH (United States); Moxley, R.T. [Univ. of Rochester Medical Center, NY (United States)

1994-03-01

Approximately one-third of Duchenne muscular dystrophy patients have undefined mutations in the dystrophin gene. For carrier and prenatal studies in families without detectable mutations, the indirect restriction fragment length polymorphism linkage approach is used. Using a multiplex amplification and heteroduplex analysis of dystrophin exons, the authors identified nonsense mutations in two DMD patients. Although the nonsense mutations are predicted to severely truncate the dystrophin protein, both patients presented with mild clinical courses of the disease. As a result of identifying the mutation in the affected boys, direct carrier studies by heteroduplex analysis were extended to other relatives. The authors conclude that the technique is not only ideal for mutation detection but is also useful for diagnostic testing. 29 refs., 4 figs.

Persistent Dystrophin Protein Restoration 90 Days after a Course of Intraperitoneally Administered Naked 2′OMePS AON and ZM2 NP-AON Complexes in mdx Mice

Directory of Open Access Journals (Sweden)

Elena Bassi

2012-01-01

Full Text Available In Duchenne muscular dystrophy, the exon-skipping approach has obtained proof of concept in animal models, myogenic cell cultures, and following local and systemic administration in Duchenne patients. Indeed, we have previously demonstrated that low doses (7.5 mg/Kg/week of 2′-O-methyl-phosphorothioate antisense oligoribonucleotides (AONs adsorbed onto ZM2 nanoparticles provoke widespread dystrophin restoration 7 days after intraperitoneal treatment in mdx mice. In this study, we went on to test whether this dystrophin restoration was still measurable 90 days from the end of the same treatment. Interestingly, we found that both western blot and immunohistochemical analysis (up to 7% positive fibres were still able to detect dystrophin protein in the skeletal muscles of ZM2-AON-treated mice at this time, and the level of exon-23 skipping could still be assessed by RT real-time PCR (up to 10% of skipping percentage. In contrast, the protein was undetectable by western blot analysis in the skeletal muscles of mdx mice treated with an identical dose of naked AON, and the percentage of dystrophin-positive fibres and exon-23 skipping were reminiscent of those of untreated mdx mice. Our data therefore demonstrate the long-term residual efficacy of this systemic low-dose treatment and confirm the protective effect nanoparticles exert on AON molecules.

Multiple Species Comparison of Cardiac Troponin T and Dystrophin: Unravelling the DNA behind Dilated Cardiomyopathy.

Science.gov (United States)

England, Jennifer; Loughna, Siobhan; Rutland, Catrin Sian

2017-07-07

Animals have frequently been used as models for human disorders and mutations. Following advances in genetic testing and treatment options, and the decreasing cost of these technologies in the clinic, mutations in both companion and commercial animals are now being investigated. A recent review highlighted the genes associated with both human and non-human dilated cardiomyopathy. Cardiac troponin T and dystrophin were observed to be associated with both human and turkey (troponin T) and canine (dystrophin) dilated cardiomyopathies. This review gives an overview of the work carried out in cardiac troponin T and dystrophin to date in both human and animal dilated cardiomyopathy.

Detection of new paternal dystrophin gene mutations in isolated cases of dystrophinopathy in females

Energy Technology Data Exchange (ETDEWEB)

Pegoraro, E.; Wessel, H.B.; Schwartz, L.; Hoffman, E.P. (Univ. of Pittsburgh, PA (United States)); Schimke, R.N. (Kansas Univ. Medical Center, Kansas City (United States)); Arahata, Kiichi; Hayashi, Yukiko (National Institute of Neurosciences, Tokyo (Japan)); Stern, H. (Children' s National Medical Center, Washington, DC (United States)); Marks, H. (A.I. duPont Institute, Wilmington (United States)); Glasberg, M.R. (Henry Ford Hospital, Detroit, MI (United States)) (and others)

1994-06-01

Duchenne muscular dystrophy is one of the most common lethal monogenic disorders and is caused by dystrophin deficiency. The disease is transmitted as an X-linked recessive trait; however, recent biochemical and clinical studies have shown that many girls and women with a primary myopathy have an underlying dystrophinopathy, despite a negative family history for Duchenne dystrophy. These isolated female dystrophinopathy patients carried ambiguous diagnoses with presumed autosomal recessive inheritance (limb-girdle muscular dystrophy) prior to biochemical detection of dystrophin abnormalities in their muscle biopsy. It has been assumed that these female dystrophinopathy patients are heterozygous carries who show preferential inactivation of the X chromosome harboring the normal dystrophin gene, although this has been shown for only a few X:autosome translocations and for two cases of discordant monozygotic twin female carriers. Here the authors study X-inactivation patterns of 13 female dystrophinopathy patients - 10 isolated cases and 3 cases with a positive family history for Duchenne dystrophy in males. They show that all cases have skewed X-inactivation patterns in peripheral blood DNA. Of the nine isolated cases informative in the assay, eight showed inheritance of the dystrophin gene mutation from the paternal germ line. Only a single case showed maternal inheritance. The 10-fold higher incidence of paternal transmission of dystrophin gene mutations in these cases is at 30-fold variance with Bayesian predictions and gene mutation rates. Thus, the results suggest some mechanistic interaction between new dystrophin gene mutations, paternal inheritance, and skewed X inactivation. The results provide both empirical risk data and a molecular diagnostic test method, which permit genetic counseling and prenatal diagnosis of this new category of patients. 58 refs., 7 figs., 2 tabs.

Evaluation of point mutations in dystrophin gene in Iranian ...

Indian Academy of Sciences (India)

5Department of Biology, Science and Research Branch, Islamic Azad ... Dystrophin protein is found ... Duchenne and Becker muscular dystrophy; neuromuscular disorder; point mutation. ..... modern diagnostic techniques to a large cohort.

A sensitive, reproducible and objective immunofluorescence analysis method of dystrophin in individual fibers in samples from patients with duchenne muscular dystrophy.

Directory of Open Access Journals (Sweden)

Chantal Beekman

Full Text Available Duchenne muscular dystrophy (DMD is characterized by the absence or reduced levels of dystrophin expression on the inner surface of the sarcolemmal membrane of muscle fibers. Clinical development of therapeutic approaches aiming to increase dystrophin levels requires sensitive and reproducible measurement of differences in dystrophin expression in muscle biopsies of treated patients with DMD. This, however, poses a technical challenge due to intra- and inter-donor variance in the occurrence of revertant fibers and low trace dystrophin expression throughout the biopsies. We have developed an immunofluorescence and semi-automated image analysis method that measures the sarcolemmal dystrophin intensity per individual fiber for the entire fiber population in a muscle biopsy. Cross-sections of muscle co-stained for dystrophin and spectrin have been imaged by confocal microscopy, and image analysis was performed using Definiens software. Dystrophin intensity has been measured in the sarcolemmal mask of spectrin for each individual muscle fiber and multiple membrane intensity parameters (mean, maximum, quantiles per fiber were calculated. A histogram can depict the distribution of dystrophin intensities for the fiber population in the biopsy. This method was tested by measuring dystrophin in DMD, Becker muscular dystrophy, and healthy muscle samples. Analysis of duplicate or quadruplicate sections of DMD biopsies on the same or multiple days, by different operators, or using different antibodies, was shown to be objective and reproducible (inter-assay precision, CV 2-17% and intra-assay precision, CV 2-10%. Moreover, the method was sufficiently sensitive to detect consistently small differences in dystrophin between two biopsies from a patient with DMD before and after treatment with an investigational compound.

Multiple Species Comparison of Cardiac Troponin T and Dystrophin: Unravelling the DNA behind Dilated Cardiomyopathy

Directory of Open Access Journals (Sweden)

Jennifer England

2017-07-01

Full Text Available Animals have frequently been used as models for human disorders and mutations. Following advances in genetic testing and treatment options, and the decreasing cost of these technologies in the clinic, mutations in both companion and commercial animals are now being investigated. A recent review highlighted the genes associated with both human and non-human dilated cardiomyopathy. Cardiac troponin T and dystrophin were observed to be associated with both human and turkey (troponin T and canine (dystrophin dilated cardiomyopathies. This review gives an overview of the work carried out in cardiac troponin T and dystrophin to date in both human and animal dilated cardiomyopathy.

The polyproline site in hinge 2 influences the functional capacity of truncated dystrophins.

Directory of Open Access Journals (Sweden)

Glen B Banks

2010-05-01

Full Text Available Mutations in dystrophin can lead to Duchenne muscular dystrophy or the more mild form of the disease, Becker muscular dystrophy. The hinge 3 region in the rod domain of dystrophin is particularly prone to deletion mutations. In-frame deletions of hinge 3 are predicted to lead to BMD, however the severity of disease can vary considerably. Here we performed extensive structure-function analyses of truncated dystrophins with modified hinges and spectrin-like repeats in mdx mice. We found that the polyproline site in hinge 2 profoundly influences the functional capacity of a microdystrophin(DeltaR4-R23/DeltaCT with a large deletion in the hinge 3 region. Inclusion of polyproline in microdystrophin(DeltaR4-R23/DeltaCT led to small myofibers (12% smaller than wild-type, Achilles myotendinous disruption, ringed fibers, and aberrant neuromuscular junctions in the mdx gastrocnemius muscles. Replacing hinge 2 of microdystrophin(DeltaR4-R23/DeltaCT with hinge 3 significantly improved the functional capacity to prevent muscle degeneration, increase muscle fiber area, and maintain the junctions. We conclude that the rigid alpha-helical structure of the polyproline site significantly impairs the functional capacity of truncated dystrophins to maintain appropriate connections between the cytoskeleton and extracellular matrix.

Comparative Analysis of Vertebrate Dystrophin Loci Indicate Intron Gigantism as a Common Feature

Science.gov (United States)

Pozzoli, Uberto; Elgar, Greg; Cagliani, Rachele; Riva, Laura; Comi, Giacomo P.; Bresolin, Nereo; Bardoni, Alessandra; Sironi, Manuela

2003-01-01

The human DMD gene is the largest known to date, spanning > 2000 kb on the X chromosome. The gene size is mainly accounted for by huge intronic regions. We sequenced 190 kb of Fugu rubripes (pufferfish) genomic DNA corresponding to the complete dystrophin gene (FrDMD) and provide the first report of gene structure and sequence comparison among dystrophin genomic sequences from different vertebrate organisms. Almost all intron positions and phases are conserved between FrDMD and its mammalian counterparts, and the predicted protein product of the Fugu gene displays 55% identity and 71% similarity to human dystrophin. In analogy to the human gene, FrDMD presents several-fold longer than average intronic regions. Analysis of intron sequences of the human and murine genes revealed that they are extremely conserved in size and that a similar fraction of total intron length is represented by repetitive elements; moreover, our data indicate that intron expansion through repeat accumulation in the two orthologs is the result of independent insertional events. The hypothesis that intron length might be functionally relevant to the DMD gene regulation is proposed and substantiated by the finding that dystrophin intron gigantism is common to the three vertebrate genes. [Supplemental material is available online at www.genome.org.] PMID:12727896

Skeletal Muscle Differentiation on a Chip Shows Human Donor Mesoangioblasts' Efficiency in Restoring Dystrophin in a Duchenne Muscular Dystrophy Model.

Science.gov (United States)

Serena, Elena; Zatti, Susi; Zoso, Alice; Lo Verso, Francesca; Tedesco, F Saverio; Cossu, Giulio; Elvassore, Nicola

2016-12-01

: Restoration of the protein dystrophin on muscle membrane is the goal of many research lines aimed at curing Duchenne muscular dystrophy (DMD). Results of ongoing preclinical and clinical trials suggest that partial restoration of dystrophin might be sufficient to significantly reduce muscle damage. Different myogenic progenitors are candidates for cell therapy of muscular dystrophies, but only satellite cells and pericytes have already entered clinical experimentation. This study aimed to provide in vitro quantitative evidence of the ability of mesoangioblasts to restore dystrophin, in terms of protein accumulation and distribution, within myotubes derived from DMD patients, using a microengineered model. We designed an ad hoc experimental strategy to miniaturize on a chip the standard process of muscle regeneration independent of variables such as inflammation and fibrosis. It is based on the coculture, at different ratios, of human dystrophin-positive myogenic progenitors and dystrophin-negative myoblasts in a substrate with muscle-like physiological stiffness and cell micropatterns. Results showed that both healthy myoblasts and mesoangioblasts restored dystrophin expression in DMD myotubes. However, mesoangioblasts showed unexpected efficiency with respect to myoblasts in dystrophin production in terms of the amount of protein produced (40% vs. 15%) and length of the dystrophin membrane domain (210-240 µm vs. 40-70 µm). These results show that our microscaled in vitro model of human DMD skeletal muscle validated previous in vivo preclinical work and may be used to predict efficacy of new methods aimed at enhancing dystrophin accumulation and distribution before they are tested in vivo, reducing time, costs, and variability of clinical experimentation. This study aimed to provide in vitro quantitative evidence of the ability of human mesoangioblasts to restore dystrophin, in terms of protein accumulation and distribution, within myotubes derived from

The influence of low dystrophin levels on disease pathology in mouse models for Duchenne Muscular Dystrophy

NARCIS (Netherlands)

Putten, Maaike van

2013-01-01

Duchenne muscular dystrophy (DMD) is the most prevalent neuromuscular disorder, caused by mutations in the DMD gene that prevent synthesis of dystrophin. Fibers that lack dystrophin are sensitive to exercise-induced damage, resulting in progressive muscle wasting, loss of ambulation and premature

Dystrophin deficiency leads to disturbance of LAMP1-vesicle-associated protein secretion

DEFF Research Database (Denmark)

Duguez, S.; Duddy, W.; Johnston, H.

2013-01-01

Duchenne muscular dystrophy results from loss of the protein dystrophin, which links the intracellular cytoskeletal network with the extracellular matrix, but deficiency in this function does not fully explain the onset or progression of the disease. While some intracellular events involved...... in the degeneration of dystrophin-deficient muscle fibers have been well characterized, changes in their secretory profile are undescribed. To analyze the secretome profile of mdx myotubes independently of myonecrosis, we labeled the proteins of mdx and wild-type myotubes with stable isotope-labeled amino acids...

Muscular dystrophy in a family of Labrador Retrievers with no muscle dystrophin and a mild phenotype.

Science.gov (United States)

Vieira, Natassia M; Guo, Ling T; Estrela, Elicia; Kunkel, Louis M; Zatz, Mayana; Shelton, G Diane

2015-05-01

Animal models of dystrophin deficient muscular dystrophy, most notably canine X-linked muscular dystrophy, play an important role in developing new therapies for human Duchenne muscular dystrophy. Although the canine disease is a model of the human disease, the variable severity of clinical presentations in the canine may be problematic for pre-clinical trials, but also informative. Here we describe a family of Labrador Retrievers with three generations of male dogs having markedly increased serum creatine kinase activity, absence of membrane dystrophin, but with undetectable clinical signs of muscle weakness. Clinically normal young male Labrador Retriever puppies were evaluated prior to surgical neuter by screening laboratory blood work, including serum creatine kinase activity. Serum creatine kinase activities were markedly increased in the absence of clinical signs of muscle weakness. Evaluation of muscle biopsies confirmed a dystrophic phenotype with both degeneration and regeneration. Further evaluations by immunofluorescence and western blot analysis confirmed the absence of muscle dystrophin. Although dystrophin was not identified in the muscles, we did not find any detectable deletions or duplications in the dystrophin gene. Sequencing is now ongoing to search for point mutations. Our findings in this family of Labrador Retriever dogs lend support to the hypothesis that, in exceptional situations, muscle with no dystrophin may be functional. Unlocking the secrets that protect these dogs from a severe clinical myopathy is a great challenge which may have important implications for future treatment of human muscular dystrophies. Copyright © 2015 Elsevier B.V. All rights reserved.

Sparks, signals and shock absorbers: how dystrophin loss causes muscular dystrophy.

Science.gov (United States)

Batchelor, Clare L; Winder, Steve J

2006-04-01

The dystrophin-glycoprotein complex (DGC) can be considered as a specialized adhesion complex, linking the extracellular matrix to the actin cytoskeleton, primarily in muscle cells. Mutations in several components of the DGC lead to its partial or total loss, resulting in various forms of muscular dystrophy. These typically manifest as progressive wasting diseases with loss of muscle integrity. Debate is ongoing about the precise function of the DGC: initially a strictly mechanical role was proposed but it has been suggested that there is aberrant calcium handling in muscular dystrophy and, more recently, changes in MAP kinase and GTPase signalling have been implicated in the aetiology of the disease. Here, we discuss new and interesting developments in these aspects of DGC function and attempt to rationalize the mechanical, calcium and signalling hypotheses to provide a unifying hypothesis of the underlying process of muscular dystrophy.

Immobilization and therapeutic passive stretching generate thickening and increase the expression of laminin and dystrophin in skeletal muscle

International Nuclear Information System (INIS)

Cação-Benedini, L.O.; Ribeiro, P.G.; Prado, C.M.; Chesca, D.L.; Mattiello-Sverzut, A.C.

2014-01-01

Extracellular matrix and costamere proteins transmit the concentric, isometric, and eccentric forces produced by active muscle contraction. The expression of these proteins after application of passive tension stimuli to muscle remains unknown. This study investigated the expression of laminin and dystrophin in the soleus muscle of rats immobilized with the right ankle in plantar flexion for 10 days and subsequent remobilization, either by isolated free movement in a cage or associated with passive stretching for up to 10 days. The intensity of the macrophage response was also evaluated. One hundred and twenty-eight female Wistar rats were divided into 8 groups: free for 10 days; immobilized for 10 days; immobilized/free for 1, 3, or 10 days; or immobilized/stretched/free for 1, 3, or 10 days. After the experimental procedures, muscle tissue was processed for immunofluorescence (dystrophin/laminin/CD68) and Western blot analysis (dystrophin/laminin). Immobilization increased the expression of dystrophin and laminin but did not alter the number of macrophages in the muscle. In the stretched muscle groups, there was an increase in dystrophin and the number of macrophages after 3 days compared with the other groups; dystrophin showed a discontinuous labeling pattern, and laminin was found in the intracellular space. The amount of laminin was increased in the muscles treated by immobilization followed by free movement for 10 days. In the initial stages of postimmobilization (1 and 3 days), an exacerbated macrophage response and an increase of dystrophin suggested that the therapeutic stretching technique induced additional stress in the muscle fibers and costameres

Immobilization and therapeutic passive stretching generate thickening and increase the expression of laminin and dystrophin in skeletal muscle

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Cação-Benedini, L.O.; Ribeiro, P.G. [Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Medicina e Reabilitação do Aparelho Locomotor, Departamento de Biomecânica, Ribeirão Preto, SP, Brasil, Departamento de Biomecânica, Medicina e Reabilitação do Aparelho Locomotor, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Prado, C.M.; Chesca, D.L. [Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Departamento de Patologia, Ribeirão Preto, SP, Brasil, Departamento de Patologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Mattiello-Sverzut, A.C. [Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Medicina e Reabilitação do Aparelho Locomotor, Departamento de Biomecânica, Ribeirão Preto, SP, Brasil, Departamento de Biomecânica, Medicina e Reabilitação do Aparelho Locomotor, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

2014-05-09

Extracellular matrix and costamere proteins transmit the concentric, isometric, and eccentric forces produced by active muscle contraction. The expression of these proteins after application of passive tension stimuli to muscle remains unknown. This study investigated the expression of laminin and dystrophin in the soleus muscle of rats immobilized with the right ankle in plantar flexion for 10 days and subsequent remobilization, either by isolated free movement in a cage or associated with passive stretching for up to 10 days. The intensity of the macrophage response was also evaluated. One hundred and twenty-eight female Wistar rats were divided into 8 groups: free for 10 days; immobilized for 10 days; immobilized/free for 1, 3, or 10 days; or immobilized/stretched/free for 1, 3, or 10 days. After the experimental procedures, muscle tissue was processed for immunofluorescence (dystrophin/laminin/CD68) and Western blot analysis (dystrophin/laminin). Immobilization increased the expression of dystrophin and laminin but did not alter the number of macrophages in the muscle. In the stretched muscle groups, there was an increase in dystrophin and the number of macrophages after 3 days compared with the other groups; dystrophin showed a discontinuous labeling pattern, and laminin was found in the intracellular space. The amount of laminin was increased in the muscles treated by immobilization followed by free movement for 10 days. In the initial stages of postimmobilization (1 and 3 days), an exacerbated macrophage response and an increase of dystrophin suggested that the therapeutic stretching technique induced additional stress in the muscle fibers and costameres.

Mouse models of two missense mutations in actin-binding domain 1 of dystrophin associated with Duchenne or Becker muscular dystrophy.

Science.gov (United States)

McCourt, Jackie L; Talsness, Dana M; Lindsay, Angus; Arpke, Robert W; Chatterton, Paul D; Nelson, D'anna M; Chamberlain, Christopher M; Olthoff, John T; Belanto, Joseph J; McCourt, Preston M; Kyba, Michael; Lowe, Dawn A; Ervasti, James M

2018-02-01

Missense mutations in the dystrophin protein can cause Duchenne muscular dystrophy (DMD) or Becker muscular dystrophy (BMD) through an undefined pathomechanism. In vitro studies suggest that missense mutations in the N-terminal actin-binding domain (ABD1) cause protein instability, and cultured myoblast studies reveal decreased expression levels that can be restored to wild-type with proteasome inhibitors. To further elucidate the pathophysiology of missense dystrophin in vivo, we generated two transgenic mdx mouse lines expressing L54R or L172H mutant dystrophin, which correspond to missense mutations identified in human patients with DMD or BMD, respectively. Our biochemical, histologic and physiologic analysis of the L54R and L172H mice show decreased levels of dystrophin which are proportional to the phenotypic severity. Proteasome inhibitors were ineffective in both the L54R and L172H mice, yet mice homozygous for the L172H transgene were able to express even higher levels of dystrophin which caused further improvements in muscle histology and physiology. Given that missense dystrophin is likely being degraded by the proteasome but whole body proteasome inhibition was not possible, we screened for ubiquitin-conjugating enzymes involved in targeting dystrophin to the proteasome. A myoblast cell line expressing L54R mutant dystrophin was screened with an siRNA library targeting E1, E2 and E3 ligases which identified Amn1, FBXO33, Zfand5 and Trim75. Our study establishes new mouse models of dystrophinopathy and identifies candidate E3 ligases that may specifically regulate dystrophin protein turnover in vivo. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Spectrum of small mutations in the dystrophin coding region

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Prior, T.W.; Bartolo, C.; Pearl, D.K. [Ohio State Univ., Columbus, OH (United States)] [and others

1995-07-01

Duchenne and Becker muscular dystrophies (DMD and BMD) are caused by defects in the dystrophin gene. About two-thirds of the affected patients have large deletions or duplications, which occur in the 5` and central portion of the gene. The nondeletion/duplication cases are most likely the result of smaller mutations that cannot be identified by current diagnostic screening strategies. We screened {approximately} 80% of the dystrophin coding sequence for small mutations in 158 patients without deletions or duplications and identified 29 mutations. The study indicates that many of the DMD and the majority of the BMD small mutations lie in noncoding regions of the gene. All of the mutations identified were unique to single patients, and most of the mutations resulted in protein truncation. We did not find a clustering of small mutations similar to the deletion distribution but found > 40% of the small mutations 3` of exon 55. The extent of protein truncation caused by the 3` mutations did not determine the phenotype, since even the exon 76 nonsense mutation resulted in the severe DMD phenotype. Our study confirms that the dystrophin gene is subject to a high rate of mutation in CpG sequences. As a consequence of not finding any hotspots or prevalent small mutations, we conclude that it is presently not possible to perform direct carrier and prenatal diagnostics for many families without deletions or duplications. 71 refs., 2 figs., 2 tabs.

Assessment of the structural and functional impact of in-frame mutations of the DMD gene, using the tools included in the eDystrophin online database

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Nicolas Aurélie

2012-07-01

Full Text Available Abstract Background Dystrophin is a large essential protein of skeletal and heart muscle. It is a filamentous scaffolding protein with numerous binding domains. Mutations in the DMD gene, which encodes dystrophin, mostly result in the deletion of one or several exons and cause Duchenne (DMD and Becker (BMD muscular dystrophies. The most common DMD mutations are frameshift mutations resulting in an absence of dystrophin from tissues. In-frame DMD mutations are less frequent and result in a protein with partial wild-type dystrophin function. The aim of this study was to highlight structural and functional modifications of dystrophin caused by in-frame mutations. Methods and results We developed a dedicated database for dystrophin, the eDystrophin database. It contains 209 different non frame-shifting mutations found in 945 patients from a French cohort and previous studies. Bioinformatics tools provide models of the three-dimensional structure of the protein at deletion sites, making it possible to determine whether the mutated protein retains the typical filamentous structure of dystrophin. An analysis of the structure of mutated dystrophin molecules showed that hybrid repeats were reconstituted at the deletion site in some cases. These hybrid repeats harbored the typical triple coiled-coil structure of native repeats, which may be correlated with better function in muscle cells. Conclusion This new database focuses on the dystrophin protein and its modification due to in-frame deletions in BMD patients. The observation of hybrid repeat reconstitution in some cases provides insight into phenotype-genotype correlations in dystrophin diseases and possible strategies for gene therapy. The eDystrophin database is freely available: http://edystrophin.genouest.org/.

Novel dystrophin mutations revealed by analysis of dystrophin mRNA: alternative splicing suppresses the phenotypic effect of a nonsense mutation

Czech Academy of Sciences Publication Activity Database

Fajkusová, L.; Lukáš, Z.; Tvrdíková, M.; Kuhrová, V.; Hájek, J.; Fajkus, Jiří

2001-01-01

Roč. 11, č. 2 (2001), s. 133-138 ISSN 0960-8966 R&D Projects: GA MZd IZ3700; GA MZd NM19; GA MZd NA5227 Institutional research plan: CEZ:AV0Z5004920 Keywords : Duchenne muscular dystrophy * Becker muscular dystrophy * dystrophin mRNA Subject RIV: BO - Biophysics Impact factor: 2.547, year: 2001

Delivery of AAV2/9-microdystrophin genes incorporating helix 1 of the coiled-coil motif in the C-terminal domain of dystrophin improves muscle pathology and restores the level of α1-syntrophin and α-dystrobrevin in skeletal muscles of mdx mice.

Science.gov (United States)

Koo, Taeyoung; Malerba, Alberto; Athanasopoulos, Takis; Trollet, Capucine; Boldrin, Luisa; Ferry, Arnaud; Popplewell, Linda; Foster, Helen; Foster, Keith; Dickson, George

2011-11-01

Duchenne muscular dystrophy is a severe X-linked inherited muscle wasting disorder caused by mutations in the dystrophin gene. Adeno-associated virus (AAV) vectors have been extensively used to deliver genes efficiently for dystrophin expression in skeletal muscles. To overcome limited packaging capacity of AAV vectors (pathology of dystrophic mdx mice. However, the CT domain of dystrophin is thought to recruit part of the dystrophin-associated protein complex, which acts as a mediator of signaling between extracellular matrix and cytoskeleton in muscle fibers. In this study, we extended the ΔR4-23/ΔCT microdystrophin by incorporating helix 1 of the coiled-coil motif in the CT domain of dystrophin (MD2), which contains the α1-syntrophin and α-dystrobrevin binding sites. Intramuscular injection of AAV2/9 expressing CT domain-extended microdystrophin showed efficient dystrophin expression in tibialis anterior muscles of mdx mice. The presence of the CT domain of dystrophin in MD2 increased the recruitment of α1-syntrophin and α-dystrobrevin at the sarcolemma and significantly improved the muscle resistance to lengthening contraction-induced muscle damage in the mdx mice compared with MD1. These results suggest that the incorporation of helix 1 of the coiled-coil motif in the CT domain of dystrophin to the microdystrophins will substantially improve their efficiency in restoring muscle function in patients with Duchenne muscular dystrophy.

Becker muscular dystrophy severity is linked to the structure of dystrophin.

Science.gov (United States)

Nicolas, Aurélie; Raguénès-Nicol, Céline; Ben Yaou, Rabah; Ameziane-Le Hir, Sarah; Chéron, Angélique; Vié, Véronique; Claustres, Mireille; Leturcq, France; Delalande, Olivier; Hubert, Jean-François; Tuffery-Giraud, Sylvie; Giudice, Emmanuel; Le Rumeur, Elisabeth

2015-03-01

In-frame exon deletions of the Duchenne muscular dystrophy (DMD) gene produce internally truncated proteins that typically lead to Becker muscular dystrophy (BMD), a milder allelic disorder of DMD. We hypothesized that differences in the structure of mutant dystrophin may be responsible for the clinical heterogeneity observed in Becker patients and we studied four prevalent in-frame exon deletions, i.e. Δ45-47, Δ45-48, Δ45-49 and Δ45-51. Molecular homology modelling revealed that the proteins corresponding to deletions Δ45-48 and Δ45-51 displayed a similar structure (hybrid repeat) than the wild-type dystrophin, whereas deletions Δ45-47 and Δ45-49 lead to proteins with an unrelated structure (fractional repeat). All four proteins in vitro expressed in a fragment encoding repeats 16-21 were folded in α-helices and remained highly stable. Refolding dynamics were slowed and molecular surface hydrophobicity were higher in fractional repeat containing Δ45-47 and Δ45-49 deletions compared with hybrid repeat containing Δ45-48 and Δ45-51 deletions. By retrospectively collecting data for a series of French BMD patients, we showed that the age of dilated cardiomyopathy (DCM) onset was delayed by 11 and 14 years in Δ45-48 and Δ45-49 compared with Δ45-47 patients, respectively. A clear trend toward earlier wheelchair dependency (minimum of 11 years) was also observed in Δ45-47 and Δ45-49 patients compared with Δ45-48 patients. Muscle dystrophin levels were moderately reduced in most patients without clear correlation with the deletion type. Disease progression in BMD patients appears to be dependent on the deletion itself and associated with a specific structure of dystrophin at the deletion site. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Deletion of Dystrophin In-Frame Exon 5 Leads to a Severe Phenotype: Guidance for Exon Skipping Strategies.

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Zhi Yon Charles Toh

Full Text Available Duchenne and Becker muscular dystrophy severity depends upon the nature and location of the DMD gene lesion and generally correlates with the dystrophin open reading frame. However, there are striking exceptions where an in-frame genomic deletion leads to severe pathology or protein-truncating mutations (nonsense or frame-shifting indels manifest as mild disease. Exceptions to the dystrophin reading frame rule are usually resolved after molecular diagnosis on muscle RNA. We report a moderate/severe Becker muscular dystrophy patient with an in-frame genomic deletion of DMD exon 5. This mutation has been reported by others as resulting in Duchenne or Intermediate muscular dystrophy, and the loss of this in-frame exon in one patient led to multiple splicing events, including omission of exon 6, that disrupts the open reading frame and is consistent with a severe phenotype. The patient described has a deletion of dystrophin exon 5 that does not compromise recognition of exon 6, and although the deletion does not disrupt the reading frame, his clinical presentation is more severe than would be expected for classical Becker muscular dystrophy. We suggest that the dystrophin isoform lacking the actin-binding sequence encoded by exon 5 is compromised, reflected by the phenotype resulting from induction of this dystrophin isoform in mouse muscle in vivo. Hence, exon skipping to address DMD-causing mutations within DMD exon 5 may not yield an isoform that confers marked clinical benefit. Additional studies will be required to determine whether multi-exon skipping strategies could yield more functional dystrophin isoforms, since some BMD patients with larger in-frame deletions in this region have been reported with mild phenotypes.

Possible influences on the expression of X chromosome-linked dystrophin abnormalities by heterozygosity for autosomal recessive Fukuyama congenital muscular dystrophy

Energy Technology Data Exchange (ETDEWEB)

Beggs, A.H.; Neumann, P.E.; Anderson, M.S.; Kunkel, L.M. (Harvard Medical School, Boston, MA (United States)); Arahata, Kiichi; Arikawa, Eri; Nonaka, Ikuya (National Inst. of Neuroscience, Tokyo (Japan))

1992-01-15

Abnormalities of dystrophin, a cytoskeletal protein of muscle and nerve, are generally considered specific for Duchenne and Becker muscular dystrophy. However, several patients have recently been identified with dystrophin deficiency who, before dystrophin testing, were considered to have Fukuyama congenital muscular dystrophy (FCMD) on the basis of clinical findings. Epidemiologic data suggest that only 1/3,500 males with autosomal recessive FCMD should have abnormal dystrophin. To explain the observation of 3/23 FCMD males with abnormal dystrophin, the authors propose that dystrophin and the FCMD gene product interact and that the earlier onset and greater severity of these patients' phenotype (relative to Duchenne muscular dystrophy) are due to their being heterozygous for the FCMD mutation in addition to being hemizygous for Duchenne muscular dystrophy, a genotype that is predicted to occur in 1/175,000 Japanese males. This model may help explain the genetic basis for some of the clinical and pathological variability seen among patients with FCMD, and it has potential implications for understanding the inheritance of other autosomal recessive disorders in general. For example, sex ratios for rare autosomal recessive disorders caused by mutations in proteins that interact with X chromosome-linked gene products may display predictable deviation from 1:1.

Intellectual Ability in the Duchenne Muscular Dystrophy and Dystrophin Gene Mutation Location

Directory of Open Access Journals (Sweden)

Rasic Milic V.

2014-12-01

Full Text Available Duchenne muscular dystrophy (DMD is the most common form of muscular dystrophy during childhood. Mutations in dystrophin (DMD gene are also recognized as a cause of cognitive impairment. We aimed to determine the association between intelligence level and mutation location in DMD genes in Serbian patients with DMD. Forty-one male patients with DMD, aged 3 to 16 years, were recruited at the Clinic for Neurology and Psychiatry for Children and Youth in Belgrade, Serbia. All patients had defined DMD gene deletions or duplications [multiplex ligation- dependent probe amplification (MLPA, polymerase chain reaction (PCR] and cognitive status assessment (Wechsler Intelligence Scale for Children, Brunet-Lezine scale, Vineland-Doll scale. In 37 patients with an estimated full scale intelligence quotient (FSIQ, six (16.22% had borderline intelligence (70dystrophin isoforms and when mutations in the 5’-untranslated region (5’UTR of Dp140 (exons 45-50 were assigned to affect only Dp427 and Dp260. Mutations affecting Dp140 and Dp71/Dp40 have been associated with more frequent and more severe cognitive impairment. Finally, the same classification of mutations explained the greater proportion of FSIQ variability associated with cumulative loss of dystrophin isoforms. In conclusion, cumulative loss of dystrophin isoforms increases the risk of intellectual impairment in DMD and characterizing the genotype can define necessity of early cognitive interventions in DMD patients.

RT-PCR analysis of dystrophin mRNA in DND/BMD patients

Energy Technology Data Exchange (ETDEWEB)

Ciafaloni, E.; Silva, H.A.R. de; Roses, A.D. [Duke Univ. Medical Center, Durham, NC (United States)

1994-09-01

Duchenne and Becker muscular dystrophies (DMD, BMD) are X-linked recessive disorders caused by mutations in the dystrophin (dys) gene. The majority of these mutations are intragenic deletions of duplications routinely detected by Southern biots and multiplex PCR. The remainder are very likely, smaller mutations, mostly point-mutations. Detection of these mutations is very difficult due to the size and complexity of the dys gene. We applied RT-PCR to analyse the entire dys mRNA of three DMD patients with no detectable genomic defect. In two unrelated patients, a duplication of the 62 bp exon 2 was identified. This causes a frameshift sufficient to explain the DMD phenotype. In the third patient, who had congenital DMD and severe mental retardation, a complex pattern of aberrant splicing at the 3-prime exons 67-79 was observed. Sural nerve biopsy in this patient showed the complete absence of Dp116. PCR-SSCP studies are presently in progress to identify the mutations responsible for the aberrant splicing patterns.

Myoblots: dystrophin quantification by in-cell western assay for a streamlined development of Duchenne muscular dystrophy (DMD) treatments.

Science.gov (United States)

Ruiz-Del-Yerro, E; Garcia-Jimenez, I; Mamchaoui, K; Arechavala-Gomeza, V

2017-10-31

New therapies for neuromuscular disorders are often mutation specific and require to be studied in patient's cell cultures. In Duchenne muscular dystrophy (DMD) dystrophin restoration drugs are being developed but as muscle cell cultures from DMD patients are scarce and do not grow or differentiate well, only a limited number of candidate drugs are tested. Moreover, dystrophin quantification by western blotting requires a large number of cultured cells; so fewer compounds are as thoroughly screened as is desirable. We aimed to develop a quantitative assessment tool using fewer cells to contribute in the study of dystrophin and to identify better drug candidates. An 'in-cell western' assay is a quantitative immunofluorescence assay performed in cell culture microplates that allows protein quantification directly in culture, allowing a higher number of experimental repeats and throughput. We have optimized the assay ('myoblot') to be applied to the study of differentiated myoblast cultures. After an exhaustive optimization of the technique to adapt it to the growth and differentiation rates of our cultures and the low intrinsic expression of our proteins of interests, our myoblot protocol allows the quantification of dystrophin and other muscle-associated proteins in muscle cell cultures. We are able to distinguish accurately between the different sets of patients based on their dystrophin expression and detect dystrophin restoration after treatment. We expect that this new tool to quantify muscle proteins in DMD and other muscle disorders will aid in their diagnosis and in the development of new therapies. © 2017 British Neuropathological Society.

Gene therapies that restore dystrophin expression for the treatment of Duchenne muscular dystrophy

Science.gov (United States)

Robinson-Hamm, Jacqueline N.; Gersbach, Charles A.

2016-01-01

Duchenne muscular dystrophy is one of the most common inherited genetic diseases and is caused by mutations to the DMD gene that encodes the dystrophin protein. Recent advances in genome editing and gene therapy offer hope for the development of potential therapeutics. Truncated versions of the DMD gene can be delivered to the affected tissues with viral vectors and show promising results in a variety of animal models. Genome editing with the CRISPR/Cas9 system has recently been used to restore dystrophin expression by deleting one or more exons of the DMD gene in patient cells and in a mouse model that led to functional improvement of muscle strength. Exon skipping with oligonucleotides has been successful in several animal models and evaluated in multiple clinical trials. Next-generation oligonucleotide formulations offer significant promise to build on these results. All these approaches to restoring dystrophin expression are encouraging, but many hurdles remain. This review summarizes the current state of these technologies and summarizes considerations for their future development. PMID:27542949

Characterization of genetic deletions in Becker muscular dystrophy using monoclonal antibodies against a deletion-prone region of dystrophin

Energy Technology Data Exchange (ETDEWEB)

Thanh, L.T.; Man, Nguyen Thi; Morris, G.E. [Wales Institute, Clwyd (United Kingdom)] [and others

1995-08-28

We have produced a new panel of 20 monoclonal antibodies (mAbs) against a region of the dystrophin protein corresponding to a deletion-prone region of the Duchenne muscular dystrophy gene (exons 45-50). We show that immunohistochemistry or Western blotting with these {open_quotes}exon-specific{close_quotes} mAbs can provide a valuable addition to Southern blotting or PCR methods for the accurate identification of genetic deletions in Becker muscular dystrophy patients. The antibodies were mapped to the following exons: exon 45 (2 mAbs), exon 46 (6), exon 47 (1), exons 47/48 (4), exons 48-50 (6), and exon 50 (1). PCR amplification of single exons or groups of exons was used both to produce specific dystrophin immunogens and to map the mAbs obtained. PCR-mediated mutagenesis was also used to identify regions of dystrophin important for mAb binding. Because the mAbs can be used to characterize the dystrophin produced by individual muscle fibres, they will also be useful for studying {open_quotes}revertant{close_quotes} fibres in Duchenne muscle and for monitoring the results of myoblast therapy trials in MD patients with deletions in this region of the dystrophin gene. 27 refs., 7 figs., 3 tabs.

Dual exon skipping in myostatin and dystrophin for Duchenne muscular dystrophy

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van Ommen Gert Jan B

2011-04-01

Full Text Available Abstract Background Myostatin is a potent muscle growth inhibitor that belongs to the Transforming Growth Factor-β (TGF-β family. Mutations leading to non functional myostatin have been associated with hypermuscularity in several organisms. By contrast, Duchenne muscular dystrophy (DMD is characterized by a loss of muscle fibers and impaired regeneration. In this study, we aim to knockdown myostatin by means of exon skipping, a technique which has been successfully applied to reframe the genetic defect of dystrophin gene in DMD patients. Methods We targeted myostatin exon 2 using antisense oligonucleotides (AON in healthy and DMD-derived myotubes cultures. We assessed the exon skipping level, transcriptional expression of myostatin and its target genes, and combined myostatin and several dystrophin AONs. These AONs were also applied in the mdx mice models via intramuscular injections. Results Myostatin AON induced exon 2 skipping in cell cultures and to a lower extent in the mdx mice. It was accompanied by decrease in myostatin mRNA and enhanced MYOG and MYF5 expression. Furthermore, combination of myostatin and dystrophin AONs induced simultaneous skipping of both genes. Conclusions We conclude that two AONs can be used to target two different genes, MSTN and DMD, in a straightforward manner. Targeting multiple ligands of TGF-beta family will be more promising as adjuvant therapies for DMD.

Complete restoration of multiple dystrophin isoforms in genetically corrected Duchenne muscular dystrophy patient–derived cardiomyocytes

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Susi Zatti

2014-01-01

Full Text Available Duchenne muscular dystrophy (DMD–associated cardiac diseases are emerging as a major cause of morbidity and mortality in DMD patients, and many therapies for treatment of skeletal muscle failed to improve cardiac function. The reprogramming of patients' somatic cells into pluripotent stem cells, combined with technologies for correcting the genetic defect, possesses great potential for the development of new treatments for genetic diseases. In this study, we obtained human cardiomyocytes from DMD patient–derived, induced pluripotent stem cells genetically corrected with a human artificial chromosome carrying the whole dystrophin genomic sequence. Stimulation by cytokines was combined with cell culturing on hydrogel with physiological stiffness, allowing an adhesion-dependent maturation and a proper dystrophin expression. The obtained cardiomyocytes showed remarkable sarcomeric organization of cardiac troponin T and α-actinin, expressed cardiac-specific markers, and displayed electrically induced calcium transients lasting less than 1 second. We demonstrated that the human artificial chromosome carrying the whole dystrophin genomic sequence is stably maintained throughout the cardiac differentiation process and that multiple promoters of the dystrophin gene are properly activated, driving expression of different isoforms. These dystrophic cardiomyocytes can be a valuable source for in vitro modeling of DMD-associated cardiac disease. Furthermore, the derivation of genetically corrected, patient-specific cardiomyocytes represents a step toward the development of innovative cell and gene therapy approaches for DMD.

Single Cell Analysis of Dystrophin and SRY Gene by Using Whole Genome Amplification

Institute of Scientific and Technical Information of China (English)

徐晨明; 金帆; 黄荷凤; 陶冶; 叶英辉

2001-01-01

Objective To develop a reliable and sensitive method for detection of sex and multiloci of Duchenne muscular dystrophy (DMD) gene in single cell Materials & methods Whole genome of single cell were amplified by using 15-base random primers (primer extension preamplification, PEP), then a small aliquot of PEP product were analyzed by using locus-specific nest PCR amplification. The procedure was evaluated by detection dystrophin exons 8, 17, 19, 44, 45, 48 and human testis-determining gene (SRY)in single lymphocytes from known sources and single blastomeres from the couples with no family history of DMD.Results The amplification efficiency rate of six dystrophin exons from single lymphocytes and single blastomeres were 97. 2% (175/180) and 100% (60/60) respectively.Results of SRY showed that 100% (15/15) amplification in single male-derived lymphocytes and 0% (0/15) amplification in single female-derived lymphocytes. Conclusion The technique of single cell PEP-nest PCR for dystrophin exons 8, 17,19, 44, 45, 48 and SRY is highly specifc. PEP-nest PCR is suitable for Preimplantation genetic diagnosis (PGD) of DMD at single cell level.

Screening of Dystrophin Gene Deletions in Egyptian Patients with DMD/BMD Muscular Dystrophies

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Laila K. Effat

2000-01-01

Full Text Available Duchenne muscular dystrophy (DMD and Becker muscular dystrophy (BMD are allelic disorders caused by mutations within the dystrophin gene. Our study has identified 100 Egyptian families collected from the Human Genetics Clinic, National Research Center, Cairo. All cases were subjected to complete clinical evaluation pedigree analysis, electromyography studies, estimation of serum creatine phosphokinase enzyme (CPK levels and DNA analysis. Multiplex PCR using 18 pairs of specific primers were used for screening of deletion mutations within the dystrophin gene. A frequency of 55% among the families. Sixty per cent of detected deletions involved multiple exons spanning the major or the minor hot spot of the dystrophin gene. The remainder 40% which mainly involved exon 45. Comparing these findings with frequencies of other countries it was found that our figures fall within the reported range of 40%– for deletions. The distribution of deletions in our study and other different studies was variable and specific ethnic differences do not apparently account for specific deletions. In addition this study concluded that employment of the 18 exon analysis is a cost effective and a highly accurate (97% to launch a nationwide program.

Concurrent Label-Free Mass Spectrometric Analysis of Dystrophin Isoform Dp427 and the Myofibrosis Marker Collagen in Crude Extracts from mdx-4cv Skeletal Muscles

Science.gov (United States)

Murphy, Sandra; Zweyer, Margit; Mundegar, Rustam R.; Henry, Michael; Meleady, Paula; Swandulla, Dieter; Ohlendieck, Kay

2015-01-01

The full-length dystrophin protein isoform of 427 kDa (Dp427), the absence of which represents the principal abnormality in X-linked muscular dystrophy, is difficult to identify and characterize by routine proteomic screening approaches of crude tissue extracts. This is probably related to its large molecular size, its close association with the sarcolemmal membrane, and its existence within a heterogeneous glycoprotein complex. Here, we used a careful extraction procedure to isolate the total protein repertoire from normal versus dystrophic mdx-4cv skeletal muscles, in conjunction with label-free mass spectrometry, and successfully identified Dp427 by proteomic means. In contrast to a considerable number of previous comparative studies of the total skeletal muscle proteome, using whole tissue proteomics we show here for the first time that the reduced expression of this membrane cytoskeletal protein is the most significant alteration in dystrophinopathy. This agrees with the pathobiochemical concept that the almost complete absence of dystrophin is the main defect in Duchenne muscular dystrophy and that the mdx-4cv mouse model of dystrophinopathy exhibits only very few revertant fibers. Significant increases in collagens and associated fibrotic marker proteins, such as fibronectin, biglycan, asporin, decorin, prolargin, mimecan, and lumican were identified in dystrophin-deficient muscles. The up-regulation of collagen in mdx-4cv muscles was confirmed by immunofluorescence microscopy and immunoblotting. Thus, this is the first mass spectrometric study of crude tissue extracts that puts the proteomic identification of dystrophin in its proper pathophysiological context. PMID:28248273

Aberrant location of inhibitory synaptic marker proteins in the hippocampus of dystrophin-deficient mice: implications for cognitive impairment in duchenne muscular dystrophy.

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Elżbieta Krasowska

Full Text Available Duchenne muscular dystrophy (DMD is a neuromuscular disease that arises from mutations in the dystrophin-encoding gene. Apart from muscle pathology, cognitive impairment, primarily of developmental origin, is also a significant component of the disorder. Convergent lines of evidence point to an important role for dystrophin in regulating the molecular machinery of central synapses. The clustering of neurotransmitter receptors at inhibitory synapses, thus impacting on synaptic transmission, is of particular significance. However, less is known about the role of dystrophin in influencing the precise expression patterns of proteins located within the pre- and postsynaptic elements of inhibitory synapses. To this end, we exploited molecular markers of inhibitory synapses, interneurons and dystrophin-deficient mouse models to explore the role of dystrophin in determining the stereotypical patterning of inhibitory connectivity within the cellular networks of the hippocampus CA1 region. In tissue from wild-type (WT mice, immunoreactivity of neuroligin2 (NL2, an adhesion molecule expressed exclusively in postsynaptic elements of inhibitory synapses, and the vesicular GABA transporter (VGAT, a marker of GABAergic presynaptic elements, were predictably enriched in strata pyramidale and lacunosum moleculare. In acute contrast, NL2 and VGAT immunoreactivity was relatively evenly distributed across all CA1 layers in dystrophin-deficient mice. Similar changes were evident with the cannabinoid receptor 1, vesicular glutamate transporter 3, parvalbumin, somatostatin and the GABAA receptor alpha1 subunit. The data show that in the absence of dystrophin, there is a rearrangement of the molecular machinery, which underlies the precise spatio-temporal pattern of GABAergic synaptic transmission within the CA1 sub-field of the hippocampus.

Phase 2a study of ataluren-mediated dystrophin production in patients with nonsense mutation Duchenne muscular dystrophy.

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Richard S Finkel

Full Text Available Approximately 13% of boys with Duchenne muscular dystrophy (DMD have a nonsense mutation in the dystrophin gene, resulting in a premature stop codon in the corresponding mRNA and failure to generate a functional protein. Ataluren (PTC124 enables ribosomal readthrough of premature stop codons, leading to production of full-length, functional proteins.This Phase 2a open-label, sequential dose-ranging trial recruited 38 boys with nonsense mutation DMD. The first cohort (n = 6 received ataluren three times per day at morning, midday, and evening doses of 4, 4, and 8 mg/kg; the second cohort (n = 20 was dosed at 10, 10, 20 mg/kg; and the third cohort (n = 12 was dosed at 20, 20, 40 mg/kg. Treatment duration was 28 days. Change in full-length dystrophin expression, as assessed by immunostaining in pre- and post-treatment muscle biopsy specimens, was the primary endpoint.Twenty three of 38 (61% subjects demonstrated increases in post-treatment dystrophin expression in a quantitative analysis assessing the ratio of dystrophin/spectrin. A qualitative analysis also showed positive changes in dystrophin expression. Expression was not associated with nonsense mutation type or exon location. Ataluren trough plasma concentrations active in the mdx mouse model were consistently achieved at the mid- and high- dose levels in participants. Ataluren was generally well tolerated.Ataluren showed activity and safety in this short-term study, supporting evaluation of ataluren 10, 10, 20 mg/kg and 20, 20, 40 mg/kg in a Phase 2b, double-blind, long-term study in nonsense mutation DMD.ClinicalTrials.gov NCT00264888.

mRNA and microRNA transcriptomics analyses in a murine model of dystrophin loss and therapeutic restoration

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Thomas C. Roberts

2016-03-01

Full Text Available Duchenne muscular dystrophy (DMD is a pediatric, X-linked, progressive muscle-wasting disorder caused by loss of function mutations affecting the gene encoding the dystrophin protein. While the primary genetic insult in DMD is well described, many details of the molecular and cellular pathologies that follow dystrophin loss are incompletely understood. To investigate gene expression in dystrophic muscle we have applied mRNA and microRNA (miRNA microarray technology to the mdx mouse model of DMD. This study was designed to generate a complete description of gene expression changes associated with dystrophic pathology and the response to an experimental therapy which restores dystrophin protein function. These datasets have enabled (1 the determination of gene expression changes associated with dystrophic pathology, (2 identification of differentially expressed genes that are restored towards wild-type levels after therapeutic dystrophin rescue, (3 investigation of the correlation between mRNA and protein expression (determined by parallel mass spectrometry proteomics analysis, and (4 prediction of pathology associated miRNA-target interactions. Here we describe in detail how the data were generated including the basic analysis as contained in the manuscript published in Human Molecular Genetics with PMID 26385637. The data have been deposited in the Gene Expression Omnibus (GEO with the accession number GSE64420.

Becker muscular dystrophy due to an intronic splicing mutation inducing a dual dystrophin transcript.

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Todeschini, Alice; Gualandi, Francesca; Trabanelli, Cecilia; Armaroli, Annarita; Ravani, Anna; Fanin, Marina; Rota, Silvia; Bello, Luca; Ferlini, Alessandra; Pegoraro, Elena; Padovani, Alessandro; Filosto, Massimiliano

2016-10-01

We describe a 29-year-old patient who complained of left thigh muscle weakness since he was 23 and of moderate proximal weakness of both lower limbs with difficulty in climbing stairs and running since he was 27. Mild weakness of iliopsoas and quadriceps muscles and muscle atrophy of both the distal forearm and thigh were observed upon clinical examination. He harboured a novel c.1150-3C>G substitution in the DMD gene, affecting the intron 10 acceptor splice site and causing exon 11 skipping and an out-of-frame transcript. However, protein of normal molecular weight but in reduced amounts was observed on Western Blot analysis. Reverse transcription analysis on muscle RNA showed production, via alternative splicing, of a transcript missing exon 11 as well as a low abundant full-length transcript which is enough to avoid the severe Duchenne phenotype. Our study showed that a reduced amount of full length dystrophin leads to a mild form of Becker muscular dystrophy. These results confirm earlier findings that low amounts of dystrophin can be associated with a milder phenotype, which is promising for therapies aiming at dystrophin restoration. Copyright © 2016 Elsevier B.V. All rights reserved.

Creation of Dystrophin Expressing Chimeric Cells of Myoblast Origin as a Novel Stem Cell Based Therapy for Duchenne Muscular Dystrophy.

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Siemionow, M; Cwykiel, J; Heydemann, A; Garcia-Martinez, J; Siemionow, K; Szilagyi, E

2018-04-01

Over the past decade different stem cell (SC) based approaches were tested to treat Duchenne Muscular Dystrophy (DMD), a lethal X-linked disorder caused by mutations in dystrophin gene. Despite research efforts, there is no curative therapy for DMD. Allogeneic SC therapies aim to restore dystrophin in the affected muscles; however, they are challenged by rejection and limited engraftment. Thus, there is a need to develop new more efficacious SC therapies. Chimeric Cells (CC), created via ex vivo fusion of donor and recipient cells, represent a promising therapeutic option for tissue regeneration and Vascularized Composite Allotransplantation (VCA) due to tolerogenic properties that eliminate the need for lifelong immunosuppression. This proof of concept study tested feasibility of myoblast fusion for Dystrophin Expressing. Chimeric Cell (DEC) therapy through in vitro characterization and in vivo assessment of engraftment, survival, and efficacy in the mdx mouse model of DMD. Murine DEC were created via ex vivo fusion of normal (snj) and dystrophin-deficient (mdx) myoblasts using polyethylene glycol. Efficacy of myoblast fusion was confirmed by flow cytometry and dystrophin immunostaining, while proliferative and myogenic differentiation capacity of DEC were assessed in vitro. Therapeutic effect after DEC transplant (0.5 × 10 6 ) into the gastrocnemius muscle (GM) of mdx mice was assessed by muscle functional tests. At 30 days post-transplant dystrophin expression in GM of injected mdx mice increased to 37.27 ± 12.1% and correlated with improvement of muscle strength and function. Our study confirmed feasibility and efficacy of DEC therapy and represents a novel SC based approach for treatment of muscular dystrophies.

Cognitive dysfunction in the dystrophin-deficient mouse model of Duchenne muscular dystrophy: A reappraisal from sensory to executive processes.

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Chaussenot, Rémi; Edeline, Jean-Marc; Le Bec, Benoit; El Massioui, Nicole; Laroche, Serge; Vaillend, Cyrille

2015-10-01

Duchenne muscular dystrophy (DMD) is associated with language disabilities and deficits in learning and memory, leading to intellectual disability in a patient subpopulation. Recent studies suggest the presence of broader deficits affecting information processing, short-term memory and executive functions. While the absence of the full-length dystrophin (Dp427) is a common feature in all patients, variable mutation profiles may additionally alter distinct dystrophin-gene products encoded by separate promoters. However, the nature of the cognitive dysfunctions specifically associated with the loss of distinct brain dystrophins is unclear. Here we show that the loss of the full-length brain dystrophin in mdx mice does not modify the perception and sensorimotor gating of auditory inputs, as assessed using auditory brainstem recordings and prepulse inhibition of startle reflex. In contrast, both acquisition and long-term retention of cued and trace fear memories were impaired in mdx mice, suggesting alteration in a functional circuit including the amygdala. Spatial learning in the water maze revealed reduced path efficiency, suggesting qualitative alteration in mdx mice learning strategy. However, spatial working memory performance and cognitive flexibility challenged in various behavioral paradigms in water and radial-arm mazes were unimpaired. The full-length brain dystrophin therefore appears to play a role during acquisition of associative learning as well as in general processes involved in memory consolidation, but no overt involvement in working memory and/or executive functions could be demonstrated in spatial learning tasks. Copyright © 2015 Elsevier Inc. All rights reserved.

Dystrophic Cardiomyopathy: Complex Pathobiological Processes to Generate Clinical Phenotype

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Takeshi Tsuda

2017-09-01

Full Text Available Duchenne muscular dystrophy (DMD, Becker muscular dystrophy (BMD, and X-linked dilated cardiomyopathy (XL-DCM consist of a unique clinical entity, the dystrophinopathies, which are due to variable mutations in the dystrophin gene. Dilated cardiomyopathy (DCM is a common complication of dystrophinopathies, but the onset, progression, and severity of heart disease differ among these subgroups. Extensive molecular genetic studies have been conducted to assess genotype-phenotype correlation in DMD, BMD, and XL-DCM to understand the underlying mechanisms of these diseases, but the results are not always conclusive, suggesting the involvement of complex multi-layers of pathological processes that generate the final clinical phenotype. Dystrophin protein is a part of dystrophin-glycoprotein complex (DGC that is localized in skeletal muscles, myocardium, smooth muscles, and neuronal tissues. Diversity of cardiac phenotype in dystrophinopathies suggests multiple layers of pathogenetic mechanisms in forming dystrophic cardiomyopathy. In this review article, we review the complex molecular interactions involving the pathogenesis of dystrophic cardiomyopathy, including primary gene mutations and loss of structural integrity, secondary cellular responses, and certain epigenetic and other factors that modulate gene expressions. Involvement of epigenetic gene regulation appears to lead to specific cardiac phenotypes in dystrophic hearts.

Duchenne muscular dystrophy diagnosed by dystrophin gene deletion test: A case report

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Rathod Kishor G, Dawre Rahul M, Kamble Milind B,Tambe Saleem H

2014-04-01

Full Text Available Duchenne muscular dystrophy (DMD is an X-linked recessive disease affecting 1 in 3600—6000 live male births. A muscle biopsy is not necessary if a genetic diagnosis is secured first, particularly as some families might view the procedure as traumatic. DMD occurs as a result of mutations (mainly deletions in the dystrophin gene (DMD; locus Xp21.2. Mutations lead to an absence of or defect in the protein dystrophin, which results in progressive muscle degeneration leading to loss of independent ambulation. Ninety percent of out frame mutations result in DMD, while 90% of in-frame mutations result in BMD. Electron microscopy is not required to confirm DMD. Genetic testing is mandatory irrespective of biopsy results. But the muscle biopsy is not required if the diagnosis is secured first by genetic testing.

A case report: Becker muscular dystrophy presenting with epilepsy and dysgnosia induced by duplication mutation of Dystrophin gene.

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Miao, Jing; Feng, Jia-Chun; Zhu, Dan; Yu, Xue-Fan

2016-12-12

Becker muscular dystrophy (BMD), a genetic disorder of X-linked recessive inheritance, typically presents with gradually progressive muscle weakness. The condition is caused by mutations of Dystrophin gene located at Xp21.2. Epilepsy is an infrequent manifestation of BMD, while cases of BMD with dysgnosia are extremely rare. We describe a 9-year-old boy with BMD, who presented with epilepsy and dysgnosia. Serum creatine kinase level was markedly elevated (3665 U/L). Wechsler intelligence tests showed a low intelligence quotient (IQ = 65). Electromyogram showed slight myogenic changes and skeletal muscle biopsy revealed muscular dystrophy. Immunohistochemical staining showed partial positivity of sarcolemma for dystrophin-N. Multiplex ligation-dependent probe amplification revealed a duplication mutation in exons 37-44 in the Dystrophin gene. The present case report helps to better understand the clinical and genetic features of BMD.

GRAF1 deficiency blunts sarcolemmal injury repair and exacerbates cardiac and skeletal muscle pathology in dystrophin-deficient mice.

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Lenhart, Kaitlin C; O'Neill, Thomas J; Cheng, Zhaokang; Dee, Rachel; Demonbreun, Alexis R; Li, Jianbin; Xiao, Xiao; McNally, Elizabeth M; Mack, Christopher P; Taylor, Joan M

2015-01-01

The plasma membranes of striated muscle cells are particularly susceptible to rupture as they endure significant mechanical stress and strain during muscle contraction, and studies have shown that defects in membrane repair can contribute to the progression of muscular dystrophy. The synaptotagmin-related protein, dysferlin, has been implicated in mediating rapid membrane repair through its ability to direct intracellular vesicles to sites of membrane injury. However, further work is required to identify the precise molecular mechanisms that govern dysferlin targeting and membrane repair. We previously showed that the bin-amphiphysin-Rvs (BAR)-pleckstrin homology (PH) domain containing Rho-GAP GTPase regulator associated with focal adhesion kinase-1 (GRAF1) was dynamically recruited to the tips of fusing myoblasts wherein it promoted membrane merging by facilitating ferlin-dependent capturing of intracellular vesicles. Because acute membrane repair responses involve similar vesicle trafficking complexes/events and because our prior studies in GRAF1-deficient tadpoles revealed a putative role for GRAF1 in maintaining muscle membrane integrity, we postulated that GRAF1 might also play an important role in facilitating dysferlin-dependent plasma membrane repair. We used an in vitro laser-injury model to test whether GRAF1 was necessary for efficient muscle membrane repair. We also generated dystrophin/GRAF1 doubledeficient mice by breeding mdx mice with GRAF1 hypomorphic mice. Evans blue dye uptake and extensive morphometric analyses were used to assess sarcolemmal integrity and related pathologies in cardiac and skeletal muscles isolated from these mice. Herein, we show that GRAF1 is dynamically recruited to damaged skeletal and cardiac muscle plasma membranes and that GRAF1-depleted muscle cells have reduced membrane healing abilities. Moreover, we show that dystrophin depletion exacerbated muscle damage in GRAF1-deficient mice and that mice with dystrophin/GRAF1

Modulation of splicing of the preceding intron by antisense oligonucleotide complementary to intra-exon sequence deleted in dystrophin Kobe

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Takeshima, Y.; Matuso, M.; Sakamoto, H.; Nishio, H. [Kobe Univ. School of Medicine and Science (Japan)

1994-09-01

Molecular analysis of dystrophin Kobe showed that exon 19 of the dystrophin gene bearing a 52 bp deletion was skipped during splicing, although the known consensus sequences at the 5{prime} and 3{prime} splice site of exon 19 were maintained. These data suggest that the deleted sequence of exon 19 may function as a cis-acting factor for exact splicing for the upstream intron. To investigate this potential role, an in vitro splicing system using dystrophin precursors was established. A two-exon precursor containing exon 18, truncated intron 18, and exon 19 was accurately spliced. However, splicing of intron 18 was dramatically inhibited when wild exon 19 was replaced with mutated exon 19. Even though the length of exon 19 was restored to normal by replacing the deleted sequence with other sequence, splicing of intron 18 was not fully reactivated. Characteristically, splicing of intron 18 was inactivated more markedly when the replaced sequence contained less polypurine stretches. These data suggested that modification of the exon sequence would result in a splicing abnormality. Antisense 31 mer 2`-O-methyl ribonucleotide was targeted against 5{prime} end of deleted region of exon 19 to modulate splicing of the mRNA precursor. Splicing of intron 18 was inhibited in a dose- and time-dependent manner. This is the first in vitro evidence to show splicing of dystrophin pre-mRNA can be managed by antisense oligonucleotides. These experiments represent an approach in which antisense oligonucleotides are used to restore the function of a defective dystrophin gene in Duchenne muscular dystrophy by inducing skipping of certain exons during splicing.

Immobilization of Dystrophin and Laminin α2-Chain Deficient Zebrafish Larvae In Vivo Prevents the Development of Muscular Dystrophy.

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Mei Li

Full Text Available Muscular dystrophies are often caused by genetic alterations in the dystrophin-dystroglycan complex or its extracellular ligands. These structures are associated with the cell membrane and provide mechanical links between the cytoskeleton and the matrix. Mechanical stress is considered a pathological mechanism and muscle immobilization has been shown to be beneficial in some mouse models of muscular dystrophy. The zebrafish enables novel and less complex models to examine the effects of extended immobilization or muscle relaxation in vivo in different dystrophy models. We have examined effects of immobilization in larvae from two zebrafish strains with muscular dystrophy, the Sapje dystrophin-deficient and the Candyfloss laminin α2-chain-deficient strains. Larvae (4 days post fertilization, dpf of both mutants have significantly lower active force in vitro, alterations in the muscle structure with gaps between muscle fibers and altered birefringence patterns compared to their normal siblings. Complete immobilization (18 hrs to 4 dpf was achieved using a small molecular inhibitor of actin-myosin interaction (BTS, 50 μM. This treatment resulted in a significantly weaker active contraction at 4 dpf in both mutated larvae and normal siblings, most likely reflecting a general effect of immobilization on myofibrillogenesis. The immobilization also significantly reduced the structural damage in the mutated strains, showing that muscle activity is an important pathological mechanism. Following one-day washout of BTS, muscle tension partly recovered in the Candyfloss siblings and caused structural damage in these mutants, indicating activity-induced muscle recovery and damage, respectively.

Long-term rescue of dystrophin expression and improvement in muscle pathology and function in dystrophic mdx mice by peptide-conjugated morpholino.

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Wu, Bo; Lu, Peijuan; Cloer, Caryn; Shaban, Mona; Grewal, Snimar; Milazi, Stephanie; Shah, Sapana N; Moulton, Hong M; Lu, Qi Long

2012-08-01

Exon skipping is capable of correcting frameshift and nonsense mutations in Duchenne muscular dystrophy. Phase 2 clinical trials in the United Kingdom and the Netherlands have reported induction of dystrophin expression in muscle of Duchenne muscular dystrophy patients by systemic administration of both phosphorodiamidate morpholino oligomers (PMO) and 2'-O-methyl phosphorothioate. Peptide-conjugated phosphorodiamidate morpholino offers significantly higher efficiency than phosphorodiamidate morpholino, with the ability to induce near-normal levels of dystrophin, and restores function in both skeletal and cardiac muscle. We examined 1-year systemic efficacy of peptide-conjugated phosphorodiamidate morpholino targeting exon 23 in dystrophic mdx mice. The LD(50) of peptide-conjugated phosphorodiamidate morpholino was determined to be approximately 85 mg/kg. The half-life of dystrophin expression was approximately 2 months in skeletal muscle, but shorter in cardiac muscle. Biweekly injection of 6 mg/kg peptide-conjugated phosphorodiamidate morpholino produced >20% dystrophin expression in all skeletal muscles and ≤5% in cardiac muscle, with improvement in muscle function and pathology and reduction in levels of serum creatine kinase. Monthly injections of 30 mg/kg peptide-conjugated phosphorodiamidate morpholino restored dystrophin to >50% normal levels in skeletal muscle, and 15% in cardiac muscle. This was associated with greatly reduced serum creatine kinase levels, near-normal histology, and functional improvement of skeletal muscle. Our results demonstrate for the first time that regular 1-year administration of peptide-conjugated phosphorodiamidate morpholino can be safely applied to achieve significant therapeutic effects in an animal model. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Electroporation Enhanced Effect of Dystrophin Splice Switching PNA Oligomers in Normal and Dystrophic Muscle

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Hjortkjær, Camilla Brolin; Shiraishi, Takehiko; Hojman, Pernille

2015-01-01

for improvement of in vivo cellular availability, we have investigated the effect of electrotransfer upon intramuscular (i.m.) PNA administration in vivo. Antisense PNA targeting exon 23 of the murine dystrophin gene was administered by i.m. injection to the tibialis anterior (TA) muscle of normal NMRI......Peptide nucleic acid (PNA) is a synthetic DNA mimic that has shown potential for discovery of novel splice switching antisense drugs. However, in vivo cellular delivery has been a limiting factor for development, and only few successful studies have been reported. As a possible modality...... switching was detected at the RNA level up to 4 weeks after a single-dose treatment. In dystrophic muscles of the MDX mouse, electroporation increased the number of dystrophin-positive fibers about 2.5-fold at 2 weeks after a single PNA administration compared to injection only. In conclusion, we find...

Tissue distribution of the dystrophin-related gene product and expression in the mdx and dy mouse

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Love, D.R.; Marsden, R.F.; Bloomfield, J.F.; Davies, K.E. (John Radcliffe Hospital, Oxford (England)); Morris, G.E.; Ellis, J.M. (North East Wales Inst., Deeside, Wales (England)); Fairbrother, U.; Edwards, Y.H. (Univ. College London (England)); Slater, C.P. (Newcastle General Hospital, Newcastle-upon-Tyne (England)); Parry, D.J. (Univ. of Ottawa, Ontario (Canada))

1991-04-15

The authors have previously reported a dystrophin-related locus (DMDL for Duchenne muscular dystrophy-like) on human chromosome 6 that maps close to the dy mutation on mouse chromosome 10. Here they show that this gene is expressed in a wide range of tissues at varying levels. The transcript is particularly abundant in several human fetal tissues, including heart, placenta, and intestine. Studies with antisera raised against a DMDL fusion protein identify a 400,000 M{sub r} protein in all mouse tissues tested, including those of mdx and dy mice. Unlike the dystrophin gene, the DMDL gene transcript is not differentially spliced at the 3{prime} end in either fetal muscle or brain.

Protein truncation test: analysis of two novel point mutations at the carboxy-terminus of the human dystrophin gene associated with mental retardation.

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Tuffery, S; Lenk, U; Roberts, R G; Coubes, C; Demaille, J; Claustres, M

1995-01-01

Approximately one-third of the mutations responsible for Duchenne muscular dytrophy (DMD) do not involve gross rearrangements of the dystrophin gene. Methods for intensive mutation screening have recently been applied to this immense gene, which resulted in the identification of a number of point mutations in DMD patients, mostly translation-terminating mutations. A number of data raised the possibility that the C-terminal region of dystrophin might be involved in some cases of mental retardation associated with DMD. Using single-strand conformation analysis of products amplified by polymerase chain reaction (PCR-SSCA) to screen the terminal domains of the dystrophin gene (exons 60-79) of 20 unrelated patients with DMD or BMD, we detected two novel point mutations in two mentally retarded DMD patients: a 1-bp deletion in exon 70 (10334delC) and a 5' splice donor site alteration in intron 69 (10294 + 1G-->T). Both mutations should result in a premature translation termination of dystrophin. The possible effects on the reading frame were analyzed by the study of reverse transcripts amplified from peripheral blood lymphocytes mRNA and by the protein truncation test.

Diseased muscles that lack dystrophin or laminin-α2 have altered compositions and proliferation of mononuclear cell populations

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Miller Jeffrey

2005-04-01

Full Text Available Abstract Background Multiple types of mononucleate cells reside among the multinucleate myofibers in skeletal muscles and these mononucleate cells function in muscle maintenance and repair. How neuromuscular disease might affect different types of muscle mononucleate cells had not been determined. In this study, therefore, we examined how two neuromuscular diseases, dystrophin-deficiency and laminin-α2-deficiency, altered the proliferation and composition of different subsets of muscle-derived mononucleate cells. Methods We used fluorescence-activated cell sorting combined with bromodeoxyuridine labeling to examine proliferation rates and compositions of mononuclear cells in diseased and healthy mouse skeletal muscle. We prepared mononucleate cells from muscles of mdx (dystrophin-deficient or Lama2-/- (laminin-α2-deficient mice and compared them to cells from healthy control muscles. We enumerated subsets of resident muscle cells based on Sca-1 and CD45 expression patterns and determined the proliferation of each cell subset in vivo by BrdU incorporation. Results We found that the proliferation and composition of the mononucleate cells in dystrophin-deficient and laminin-α2-deficient diseased muscles are different than in healthy muscle. The mdx and Lama2-/- muscles showed similar significant increases in CD45+ cells compared to healthy muscle. Changes in proliferation, however, differed between the two diseases with proliferation increased in mdx and decreased in Lama2-/- muscles compared to healthy muscles. In particular, the most abundant Sca-1-/CD45- subset, which contains muscle precursor cells, had increased proliferation in mdx muscle but decreased proliferation in Lama2-/- muscles. Conclusion The similar increases in CD45+ cells, but opposite changes in proliferation of muscle precursor cells, may underlie aspects of the distinct pathologies in the two diseases.

Restoration of half the normal dystrophin sequence in a double-deletion Duchenne muscular dystrophy family

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Hoop, R.C.; Schwartz, L.S.; Hoffman, E.P. [Univ. of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Russo, L.S. [Univ. of Florida, Jacksonville, FL (United States); Riconda, D.L. [Orlando Regional Medical Center, Orlando, FL (United States)

1994-02-01

Two male cousins with Duchenne muscular dystrophy were found to have different maternal dystrophin gene haplotypes and different deletion mutations. One propositus showed two noncontiguous deletions-one in the 5{prime}, proximal deletional hotspot region, and the other in the 3{prime}, more distal deletional hotspot region. The second propositus showed only the 5{prime} deletion. Using multiple fluorescent exon dosage and fluorescent multiplex CA repeat linkage analyses, the authors show that the mother of each propositus carries both deletions on the same grandmaternal X chromosome. This paradox is explained by a single recombinational event between the 2 deleted regions of one of the carrier`s dystrophin genes, giving rise to a son with a partially {open_quotes}repaired{close_quotes} gene retaining only the 5{prime} deletion. 20 refs., 4 figs.

The proton pump inhibitor lansoprazole improves the skeletal phenotype in dystrophin deficient mdx mice.

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Arpana Sali

Full Text Available In Duchenne muscular dystrophy (DMD, loss of the membrane stabilizing protein dystrophin results in myofiber damage. Microinjury to dystrophic myofibers also causes secondary imbalances in sarcolemmic ion permeability and resting membrane potential, which modifies excitation-contraction coupling and increases proinflammatory/apoptotic signaling cascades. Although glucocorticoids remain the standard of care for the treatment of DMD, there is a need to investigate the efficacy of other pharmacological agents targeting the involvement of imbalances in ion flux on dystrophic pathology.We designed a preclinical trial to investigate the effects of lansoprazole (LANZO administration, a proton pump inhibitor, on the dystrophic muscle phenotype in dystrophin deficient (mdx mice. Eight to ten week-old female mice were assigned to one of four treatment groups (n = 12 per group: (1 vehicle control; (2 5 mg/kg/day LANZO; (3 5 mg/kg/day prednisolone; and (4 combined treatment of 5 mg/kg/day prednisolone (PRED and 5 mg/kg/day LANZO. Treatment was administered orally 5 d/wk for 3 months. At the end of the study, behavioral (Digiscan and functional outcomes (grip strength and Rotarod were assessed prior to sacrifice. After sacrifice, body, tissue and organ masses, muscle histology, in vitro muscle force, and creatine kinase levels were measured. Mice in the combined treatment groups displayed significant reductions in the number of degenerating muscle fibers and number of inflammatory foci per muscle field relative to vehicle control. Additionally, mice in the combined treatment group displayed less of a decline in normalized forelimb and hindlimb grip strength and declines in in vitro EDL force after repeated eccentric contractions.Together our findings suggest that combined treatment of LANZO and prednisolone attenuates some components of dystrophic pathology in mdx mice. Our findings warrant future investigation of the clinical efficacy of LANZO and

Clinical and genetic characterisation of dystrophin-deficient muscular dystrophy in a family of Miniature Poodle dogs.

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Lluís Sánchez

Full Text Available Four full-sibling intact male Miniature Poodles were evaluated at 4-19 months of age. One was clinically normal and three were affected. All affected dogs were reluctant to exercise and had generalised muscle atrophy, a stiff gait and a markedly elevated serum creatine kinase activity. Two affected dogs also showed poor development, learning difficulties and episodes of abnormal behaviour. In these two dogs, investigations into forebrain structural and metabolic diseases were unremarkable; electromyography demonstrated fibrillation potentials and complex repetitive discharges in the infraspinatus, supraspinatus and epaxial muscles. Histopathological, immunohistochemical and immunoblotting analyses of muscle biopsies were consistent with dystrophin-deficient muscular dystrophy. DNA samples were obtained from all four full-sibling male Poodles, a healthy female littermate and the dam, which was clinically normal. Whole genome sequencing of one affected dog revealed a >5 Mb deletion on the X chromosome, encompassing the entire DMD gene. The exact deletion breakpoints could not be experimentally ascertained, but we confirmed that this region was deleted in all affected males, but not in the unaffected dogs. Quantitative polymerase chain reaction confirmed all three affected males were hemizygous for the mutant X chromosome, while the wildtype chromosome was observed in the unaffected male littermate. The female littermate and the dam were both heterozygous for the mutant chromosome. Forty-four Miniature Poodles from the general population were screened for the mutation and were homozygous for the wildtype chromosome. The finding represents a naturally-occurring mutation causing dystrophin-deficient muscular dystrophy in the dog.

Deletion of exon 26 of the dystrophin gene is associated with a mild Becker muscular dystrophy phenotype

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Witting, Nanna; Duno, Morten; Vissing, John

2011-01-01

With the possible introduction of exon skipping therapy in Duchenne muscular dystrophy, it has become increasingly important to know the role of each exon of the dystrophin gene to protein expression, and thus the phenotype. In this report, we present two related men with an unusually mild BMD...... calf hypertrophy was noted. Creatine kinase was normal or raised maximally to 500 U/l. The muscle biopsy was myopathic with increased fiber size variation and many internal nuclei, but no dystrophy. No comorbidity was found. In both cases, western blot showed a reduced dystrophin band. Genetic...... skipping therapy for Duchenne muscular dystrophy. This report also shows that BMD may present with a normal CK....

Identification of small molecule and genetic modulators of AON-induced dystrophin exon skipping by high-throughput screening.

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Debra A O'Leary

Full Text Available One therapeutic approach to Duchenne Muscular Dystrophy (DMD recently entering clinical trials aims to convert DMD phenotypes to that of a milder disease variant, Becker Muscular Dystrophy (BMD, by employing antisense oligonucleotides (AONs targeting splice sites, to induce exon skipping and restore partial dystrophin function. In order to search for small molecule and genetic modulators of AON-dependent and independent exon skipping, we screened approximately 10,000 known small molecule drugs, >17,000 cDNA clones, and >2,000 kinase- targeted siRNAs against a 5.6 kb luciferase minigene construct, encompassing exon 71 to exon 73 of human dystrophin. As a result, we identified several enhancers of exon skipping, acting on both the reporter construct as well as endogenous dystrophin in mdx cells. Multiple mechanisms of action were identified, including histone deacetylase inhibition, tubulin modulation and pre-mRNA processing. Among others, the nucleolar protein NOL8 and staufen RNA binding protein homolog 2 (Stau2 were found to induce endogenous exon skipping in mdx cells in an AON-dependent fashion. An unexpected but recurrent theme observed in our screening efforts was the apparent link between the inhibition of cell cycle progression and the induction of exon skipping.

Cloning of human basic A1, a distinct 59-kDa dystrophin-associated protein encoded on chromosome 8q23-24

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Ahn, A.H. [Harvard Medical School, Boston, MA (United States); Yoshida, Mikiharu; Hagiwara, Yasuko; Ozawa, Eijiro [National Institute of Neuroscience, Ogawa Higashi, Kodaira (Japan); Anderson, M.S.; Feener, C.A.; Selig, S. [Howard Hughes Medical Institute at Children`s Hospital, Boston, MA (United States); Kunkel, L.M. [Harvard Medical School, Boston, MA (United States)]|[Howard Hughes Medical Institute at Children`s Hosptial, Boston, MA (United States)

1994-05-10

Duchenne and Becker muscular dystrophies are caused by defects of dystrophin, which forms a part of the membrane cytoskeleton of specialized cells such as muscle. It has been previously shown that the dystrophin-associated protein A1 (59-kDa DAP) is actually a heterogeneous group of phosphorylated proteins consisting of an acidic ({alpha}-A1) and a distinct basic ({beta}-A1) component. Partial peptide sequence of the A1 complex purified from rabbit muscle permitted the design of oligonucleotide probes that were used to isolate a cDNA for one human isoform of A1. This cDNA encodes a basic A1 isoform that is distinct from the recently described syntrophins in Torpedo and mouse and is expressed in many tissues with at least five distinct mRNA species of 5.9, 4.8, 4.3, 3.1, and 1.5 kb. A comparison of the human cDNA sequence with the GenBank expressed sequence tag (EST) data base has identified a relative from human skeletal muscle, EST25263, which is probably a human homologue of the published mouse syntrophin 2. The authors have mapped the human basic component of A1 and EST25263 genes to chromosomes 8q23-24 and 16, respectively.

Gentamicin treatment in exercised mdx mice: Identification of dystrophin-sensitive pathways and evaluation of efficacy in work-loaded dystrophic muscle.

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De Luca, Annamaria; Nico, Beatrice; Rolland, Jean-François; Cozzoli, Anna; Burdi, Rosa; Mangieri, Domenica; Giannuzzi, Viviana; Liantonio, Antonella; Cippone, Valentina; De Bellis, Michela; Nicchia, Grazia Paola; Camerino, Giulia Maria; Frigeri, Antonio; Svelto, Maria; Camerino, Diana Conte

2008-11-01

Aminoglycosides force read through of premature stop codon mutations and introduce new mutation-specific gene-corrective strategies in Duchenne muscular dystrophy. A chronic treatment with gentamicin (32 mg/kg/daily i.p., 8-12 weeks) was performed in exercised mdx mice with the dual aim to clarify the dependence on dystrophin of the functional, biochemical and histological alterations present in dystrophic muscle and to verify the long term efficiency of small molecule gene-corrective strategies in work-loaded dystrophic muscle. The treatment counteracted the exercise-induced impairment of in vivo forelimb strength after 6-8 weeks. We observed an increase in dystrophin expression level in all the fibers, although lower than that observed in normal fibers, and found a concomitant recovery of aquaporin-4 at sarcolemma. A significant reduction in centronucleated fibers, in the area of necrosis and in the percentage of nuclear factor-kB-positive nuclei was observed in gastrocnemious muscle of treated animals. Plasma creatine kinase was reduced by 70%. Ex vivo, gentamicin restored membrane ionic conductance in mdx diaphragm and limb muscle fibers. No effects were observed on the altered calcium homeostasis and sarcolemmal calcium permeability, detected by electrophysiological and microspectrofluorimetric approaches. Thus, the maintenance of a partial level of dystrophin is sufficient to reinforce sarcolemmal stability, reducing leakiness, inflammation and fiber damage, while correction of altered calcium homeostasis needs greater expression of dystrophin or direct interventions on the channels involved.

Motor physical therapy affects muscle collagen type I and decreases gait speed in dystrophin-deficient dogs.

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Thaís P Gaiad

Full Text Available Golden Retriever Muscular Dystrophy (GRMD is a dystrophin-deficient canine model genetically homologous to Duchenne Muscular Dystrophy (DMD in humans. Muscular fibrosis secondary to cycles of degeneration/regeneration of dystrophic muscle tissue and muscular weakness leads to biomechanical adaptation that impairs the quality of gait. Physical therapy (PT is one of the supportive therapies available for DMD, however, motor PT approaches have controversial recommendations and there is no consensus regarding the type and intensity of physical therapy. In this study we investigated the effect of physical therapy on gait biomechanics and muscular collagen deposition types I and III in dystrophin-deficient dogs. Two dystrophic dogs (treated dogs-TD underwent a PT protocol of active walking exercise, 3×/week, 40 minutes/day, 12 weeks. Two dystrophic control dogs (CD maintained their routine of activities of daily living. At t0 (pre and t1 (post-physical therapy, collagen type I and III were assessed by immunohistochemistry and gait biomechanics were analyzed. Angular displacement of shoulder, elbow, carpal, hip, stifle and tarsal joint and vertical (Fy, mediolateral (Fz and craniocaudal (Fx ground reaction forces (GRF were assessed. Wilcoxon test was used to verify the difference of biomechanical variables between t0 and t1, considering p<.05. Type I collagen of endomysium suffered the influence of PT, as well as gait speed that had decreased from t0 to t1 (p<.000. The PT protocol employed accelerates morphological alterations on dystrophic muscle and promotes a slower velocity of gait. Control dogs which maintained their routine of activities of daily living seem to have found a better balance between movement and preservation of motor function.

Motor Physical Therapy Affects Muscle Collagen Type I and Decreases Gait Speed in Dystrophin-Deficient Dogs

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Gaiad, Thaís P.; Araujo, Karla P. C.; Serrão, Júlio C.; Miglino, Maria A.; Ambrósio, Carlos Eduardo

2014-01-01

Golden Retriever Muscular Dystrophy (GRMD) is a dystrophin-deficient canine model genetically homologous to Duchenne Muscular Dystrophy (DMD) in humans. Muscular fibrosis secondary to cycles of degeneration/regeneration of dystrophic muscle tissue and muscular weakness leads to biomechanical adaptation that impairs the quality of gait. Physical therapy (PT) is one of the supportive therapies available for DMD, however, motor PT approaches have controversial recommendations and there is no consensus regarding the type and intensity of physical therapy. In this study we investigated the effect of physical therapy on gait biomechanics and muscular collagen deposition types I and III in dystrophin-deficient dogs. Two dystrophic dogs (treated dogs-TD) underwent a PT protocol of active walking exercise, 3×/week, 40 minutes/day, 12 weeks. Two dystrophic control dogs (CD) maintained their routine of activities of daily living. At t0 (pre) and t1 (post-physical therapy), collagen type I and III were assessed by immunohistochemistry and gait biomechanics were analyzed. Angular displacement of shoulder, elbow, carpal, hip, stifle and tarsal joint and vertical (Fy), mediolateral (Fz) and craniocaudal (Fx) ground reaction forces (GRF) were assessed. Wilcoxon test was used to verify the difference of biomechanical variables between t0 and t1, considering p<.05. Type I collagen of endomysium suffered the influence of PT, as well as gait speed that had decreased from t0 to t1 (p<.000). The PT protocol employed accelerates morphological alterations on dystrophic muscle and promotes a slower velocity of gait. Control dogs which maintained their routine of activities of daily living seem to have found a better balance between movement and preservation of motor function. PMID:24713872

The evolution of the dystroglycan complex, a major mediator of muscle integrity

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Josephine C. Adams

2015-09-01

Full Text Available Basement membrane (BM extracellular matrices are crucial for the coordination of different tissue layers. A matrix adhesion receptor that is important for BM function and stability in many mammalian tissues is the dystroglycan (DG complex. This comprises the non-covalently-associated extracellular α-DG, that interacts with laminin in the BM, and the transmembrane β-DG, that interacts principally with dystrophin to connect to the actin cytoskeleton. Mutations in dystrophin, DG, or several enzymes that glycosylate α-DG underlie severe forms of human muscular dystrophy. Nonwithstanding the pathophysiological importance of the DG complex and its fundamental interest as a non-integrin system of cell-ECM adhesion, the evolution of DG and its interacting proteins is not understood. We analysed the phylogenetic distribution of DG, its proximal binding partners and key processing enzymes in extant metazoan and relevant outgroups. We identify that DG originated after the divergence of ctenophores from porifera and eumetazoa. The C-terminal half of the DG core protein is highly-conserved, yet the N-terminal region, that includes the laminin-binding region, has undergone major lineage-specific divergences. Phylogenetic analysis based on the C-terminal IG2_MAT_NU region identified three distinct clades corresponding to deuterostomes, arthropods, and mollusks/early-diverging metazoans. Whereas the glycosyltransferases that modify α-DG are also present in choanoflagellates, the DG-binding proteins dystrophin and laminin originated at the base of the metazoa, and DG-associated sarcoglycan is restricted to cnidarians and bilaterians. These findings implicate extensive functional diversification of DG within invertebrate lineages and identify the laminin-DG-dystrophin axis as a conserved adhesion system that evolved subsequent to integrin-ECM adhesion, likely to enhance the functional complexity of cell-BM interactions in early metazoans.

[Clinical features of patients with Becker muscular dystrophy and deletions of the rod domain of dystrophin gene].

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Wang, Yanyun; Zhu, Yuling; Yang, Juan; Li, Yaqin; Sun, Jiangwen; Zhan, Yixin; Zhang, Cheng

2018-02-10

OBJECTIVE To explore the clinical features of patients carrying deletions of the rod domain of the dystrophin gene. METHODS Clinical data of 12 Chinese patients with Becker muscular dystrophy (BMD) and such deletions was reviewed. RESULTS Most patients complained of muscle weakness of lower limbs. Two patients had muscle cramps, one had increased creatine kinase (CK) level, and one had dilated cardiomyopathy. CONCLUSION Compared with DMD, the clinical features of BMD are much more variable, particularly for those carrying deletions of the rod domain of the dystrophin gene. Muscular weakness may not be the sole complaint of BMD. The diagnosis of BMD cannot be excluded by moderately elevated CK. For male patients with dilated cardiomyopathy, the possibility of BMD should be considered.

Relatively low proportion of dystrophin gene deletions in Israeili Duchenne and Becker muscular dystrophy patients

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Shomrat, R.; Gluck, E.; Legum, C.; Shiloh, Y. [Tel Aviv Univ. (Israel)

1994-02-15

Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are allelic disorders caused by mutations in the X-linked dystrophin gene. The most common mutations in western populations are deletions that are spread non-randomly throughout the gene. Molecular analysis of the dystrophin gene structure by hybridization of the full length cDNA to Southern blots and by PCR in 62 unrelated Israeli male DMD/BMD patients showed deletions in 23 (37%). This proportion is significantly lower than that found in European and North American populations (55-65%). Seventy-eight percent of the deletions were confined to exons 44-52, half of these exons 44-45, and the remaining 22% to exons 1 and 19. There was no correlation between the size of the deletion and the severity of the disease. All the deletions causing frameshift resulted in the DMD phenotypes. 43 refs., 1 fig., 1 tab.

Fetal microchimeric cells in a fetus-treats-its-mother paradigm do not contribute to dystrophin production in serially parous mdx females.

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Seppanen, Elke Jane; Hodgson, Samantha Susan; Khosrotehrani, Kiarash; Bou-Gharios, George; Fisk, Nicholas M

2012-10-10

Throughout every pregnancy, genetically distinct fetal microchimeric stem/progenitor cells (FMCs) engraft in the mother, persist long after delivery, and may home to damaged maternal tissues. Phenotypically normal fetal lymphoid progenitors have been described to develop in immunodeficient mothers in a fetus-treats-its-mother paradigm. Since stem cells contribute to muscle repair, we assessed this paradigm in the mdx mouse model of Duchenne muscular dystrophy. mdx females were bred serially to either ROSAeGFP males or mdx males to obtain postpartum microchimeras that received either wild-type FMCs or dystrophin-deficient FMCs through serial gestations. To enhance regeneration, notexin was injected into the tibialis anterior of postpartum mice. FMCs were detected by qPCR at a higher frequency in injected compared to noninjected side muscle (P=0.02). However, the number of dystrophin-positive fibers was similar in mothers delivering wild-type compared to mdx pups. In addition, there was no correlation between FMC detection and percentage dystrophin, and no GFP+ve FMCs were identified that expressed dystrophin. In 10/11 animals, GFP+ve FMCs were detected by immunohistochemistry, of which 60% expressed CD45 with 96% outside the basal lamina defining myofiber contours. Finally we confirmed lack of FMC contribution to statellite cells in postpartum mdx females mated with Myf5-LacZ males. We conclude that the FMC contribution to regenerating muscles is insufficient to have a functional impact.

Optimization of Peptide Nucleic Acid Antisense Oligonucleotides for Local and Systemic Dystrophin Splice Correction in the mdx Mouse

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Yin, HaiFang; Betts, Corinne; Saleh, Amer F; Ivanova, Gabriela D; Lee, Hyunil; Seow, Yiqi; Kim, Dalsoo; Gait, Michael J; Wood, Matthew JA

2010-01-01

Antisense oligonucleotides (AOs) have the capacity to alter the processing of pre-mRNA transcripts in order to correct the function of aberrant disease-related genes. Duchenne muscular dystrophy (DMD) is a fatal X-linked muscle degenerative disease that arises from mutations in the DMD gene leading to an absence of dystrophin protein. AOs have been shown to restore the expression of functional dystrophin via splice correction by intramuscular and systemic delivery in animal models of DMD and in DMD patients via intramuscular administration. Major challenges in developing this splice correction therapy are to optimize AO chemistry and to develop more effective systemic AO delivery. Peptide nucleic acid (PNA) AOs are an alternative AO chemistry with favorable in vivo biochemical properties and splice correcting abilities. Here, we show long-term splice correction of the DMD gene in mdx mice following intramuscular PNA delivery and effective splice correction in aged mdx mice. Further, we report detailed optimization of systemic PNA delivery dose regimens and PNA AO lengths to yield splice correction, with 25-mer PNA AOs providing the greatest splice correcting efficacy, restoring dystrophin protein in multiple peripheral muscle groups. PNA AOs therefore provide an attractive candidate AO chemistry for DMD exon skipping therapy. PMID:20068555

Characterization of dystrophin deficient rats: a new model for Duchenne muscular dystrophy.

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Larcher, Thibaut; Lafoux, Aude; Tesson, Laurent; Remy, Séverine; Thepenier, Virginie; François, Virginie; Le Guiner, Caroline; Goubin, Helicia; Dutilleul, Maéva; Guigand, Lydie; Toumaniantz, Gilles; De Cian, Anne; Boix, Charlotte; Renaud, Jean-Baptiste; Cherel, Yan; Giovannangeli, Carine; Concordet, Jean-Paul; Anegon, Ignacio; Huchet, Corinne

2014-01-01

A few animal models of Duchenne muscular dystrophy (DMD) are available, large ones such as pigs or dogs being expensive and difficult to handle. Mdx (X-linked muscular dystrophy) mice only partially mimic the human disease, with limited chronic muscular lesions and muscle weakness. Their small size also imposes limitations on analyses. A rat model could represent a useful alternative since rats are small animals but 10 times bigger than mice and could better reflect the lesions and functional abnormalities observed in DMD patients. Two lines of Dmd mutated-rats (Dmdmdx) were generated using TALENs targeting exon 23. Muscles of animals of both lines showed undetectable levels of dystrophin by western blot and less than 5% of dystrophin positive fibers by immunohistochemistry. At 3 months, limb and diaphragm muscles from Dmdmdx rats displayed severe necrosis and regeneration. At 7 months, these muscles also showed severe fibrosis and some adipose tissue infiltration. Dmdmdx rats showed significant reduction in muscle strength and a decrease in spontaneous motor activity. Furthermore, heart morphology was indicative of dilated cardiomyopathy associated histologically with necrotic and fibrotic changes. Echocardiography showed significant concentric remodeling and alteration of diastolic function. In conclusion, Dmdmdx rats represent a new faithful small animal model of DMD.

Precise correction of the dystrophin gene in duchenne muscular dystrophy patient induced pluripotent stem cells by TALEN and CRISPR-Cas9.

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Li, Hongmei Lisa; Fujimoto, Naoko; Sasakawa, Noriko; Shirai, Saya; Ohkame, Tokiko; Sakuma, Tetsushi; Tanaka, Michihiro; Amano, Naoki; Watanabe, Akira; Sakurai, Hidetoshi; Yamamoto, Takashi; Yamanaka, Shinya; Hotta, Akitsu

2015-01-13

Duchenne muscular dystrophy (DMD) is a severe muscle-degenerative disease caused by a mutation in the dystrophin gene. Genetic correction of patient-derived induced pluripotent stem cells (iPSCs) by TALENs or CRISPR-Cas9 holds promise for DMD gene therapy; however, the safety of such nuclease treatment must be determined. Using a unique k-mer database, we systematically identified a unique target region that reduces off-target sites. To restore the dystrophin protein, we performed three correction methods (exon skipping, frameshifting, and exon knockin) in DMD-patient-derived iPSCs, and found that exon knockin was the most effective approach. We further investigated the genomic integrity by karyotyping, copy number variation array, and exome sequencing to identify clones with a minimal mutation load. Finally, we differentiated the corrected iPSCs toward skeletal muscle cells and successfully detected the expression of full-length dystrophin protein. These results provide an important framework for developing iPSC-based gene therapy for genetic disorders using programmable nucleases. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Dystrophin-deficient cardiomyocytes derived from human urine: New biologic reagents for drug discovery

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Xuan Guan

2014-03-01

Full Text Available The ability to extract somatic cells from a patient and reprogram them to pluripotency opens up new possibilities for personalized medicine. Induced pluripotent stem cells (iPSCs have been employed to generate beating cardiomyocytes from a patient's skin or blood cells. Here, iPSC methods were used to generate cardiomyocytes starting from the urine of a patient with Duchenne muscular dystrophy (DMD. Urine was chosen as a starting material because it contains adult stem cells called urine-derived stem cells (USCs. USCs express the canonical reprogramming factors c-myc and klf4, and possess high telomerase activity. Pluripotency of urine-derived iPSC clones was confirmed by immunocytochemistry, RT-PCR and teratoma formation. Urine-derived iPSC clones generated from healthy volunteers and a DMD patient were differentiated into beating cardiomyocytes using a series of small molecules in monolayer culture. Results indicate that cardiomyocytes retain the DMD patient's dystrophin mutation. Physiological assays suggest that dystrophin-deficient cardiomyocytes possess phenotypic differences from normal cardiomyocytes. These results demonstrate the feasibility of generating cardiomyocytes from a urine sample and that urine-derived cardiomyocytes retain characteristic features that might be further exploited for mechanistic studies and drug discovery.

Nanopatterned muscle cell patches for enhanced myogenesis and dystrophin expression in a mouse model of muscular dystrophy.

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Yang, Hee Seok; Ieronimakis, Nicholas; Tsui, Jonathan H; Kim, Hong Nam; Suh, Kahp-Yang; Reyes, Morayma; Kim, Deok-Ho

2014-02-01

Skeletal muscle is a highly organized tissue in which the extracellular matrix (ECM) is composed of highly-aligned cables of collagen with nanoscale feature sizes, and provides structural and functional support to muscle fibers. As such, the transplantation of disorganized tissues or the direct injection of cells into muscles for regenerative therapy often results in suboptimal functional improvement due to a failure to integrate with native tissue properly. Here, we present a simple method in which biodegradable, biomimetic substrates with precisely controlled nanotopography were fabricated using solvent-assisted capillary force lithography (CFL) and were able to induce the proper development and differentiation of primary mononucleated cells to form mature muscle patches. Cells cultured on these nanopatterned substrates were highly-aligned and elongated, and formed more mature myotubes as evidenced by up-regulated expression of the myogenic regulatory factors Myf5, MyoD and myogenin (MyoG). When transplanted into mdx mice models for Duchenne muscular dystrophy (DMD), the proposed muscle patches led to the formation of a significantly greater number of dystrophin-positive muscle fibers, indicating that dystrophin replacement and myogenesis is achievable in vivo with this approach. These results demonstrate the feasibility of utilizing biomimetic substrates not only as platforms for studying the influences of the ECM on skeletal muscle function and maturation, but also to create transplantable muscle cell patches for the treatment of chronic and acute muscle diseases or injuries. Copyright © 2013 Elsevier Ltd. All rights reserved.

Serum cholinesterases are differentially regulated in normal and dystrophin-deficient mutant mice

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Andrea R. Durrant

2012-06-01

Full Text Available The cholinesterases, acetylcholinesterase and butyrylcholinesterase (pseudocholinesterase, are abundant in the nervous system and in other tissues. The role of acetylcholinesterase in terminating transmitter action in the peripheral and central nervous system is well understood. However, both knowledge of the function(s of the cholinesterases in serum, and of their metabolic and endocrine regulation under normal and pathological conditions, is limited. This study investigates acetylcholinesterase and butyrylcholinesterase in sera of dystrophin-deficient mdx mutant mice, an animal model for the human Duchenne muscular dystrophy and in control healthy mice. The data show systematic and differential variations in the concentrations of both enzymes in the sera, and specific changes dictated by alteration of hormonal balance in both healthy and dystrophic mice. While acetylcholinesterase in mdx-sera is elevated, butyrylcholinesterase is markedly diminished, resulting in an overall cholinesterase decrease compared to sera of healthy controls. The androgen testosterone (T is a negative modulator of butyrylcholinesterase, but not of acetylcholinesterase, in male mouse sera. T-removal elevated both butyrylcholinesterase activity and the butyrylcholinesterase/acetylcholinesterase ratio in mdx male sera to values resembling those in healthy control male mice. Mechanisms of regulation of the circulating cholinesterases and their impairment in the dystrophic mice are suggested, and clinical implications for diagnosis and treatment are considered.

Context Dependent Effects of Chimeric Peptide Morpholino Conjugates Contribute to Dystrophin Exon-skipping Efficiency.

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Yin, Haifang; Boisguerin, Prisca; Moulton, Hong M; Betts, Corinne; Seow, Yiqi; Boutilier, Jordan; Wang, Qingsong; Walsh, Anthony; Lebleu, Bernard; Wood, Matthew Ja

2013-09-24

We have recently reported that cell-penetrating peptides (CPPs) and novel chimeric peptides containing CPP (referred as B peptide) and muscle-targeting peptide (referred as MSP) motifs significantly improve the systemic exon-skipping activity of morpholino phosphorodiamidate oligomers (PMOs) in dystrophin-deficient mdx mice. In the present study, the general mechanistic significance of the chimeric peptide configuration on the activity and tissue uptake of peptide conjugated PMOs in vivo was investigated. Four additional chimeric peptide-PMO conjugates including newly identified peptide 9 (B-9-PMO and 9-B-PMO) and control peptide 3 (B-3-PMO and 3-B-PMO) were tested in mdx mice. Immunohistochemical staining, RT-PCR and western blot results indicated that B-9-PMO induced significantly higher level of exon skipping and dystrophin restoration than its counterpart (9-B-PMO), further corroborating the notion that the activity of chimeric peptide-PMO conjugates is dependent on relative position of the tissue-targeting peptide motif within the chimeric peptide with respect to PMOs. Subsequent mechanistic studies showed that enhanced cellular uptake of B-MSP-PMO into muscle cells leads to increased exon-skipping activity in comparison with MSP-B-PMO. Surprisingly, further evidence showed that the uptake of chimeric peptide-PMO conjugates of both orientations (B-MSP-PMO and MSP-B-PMO) was ATP- and temperature-dependent and also partially mediated by heparan sulfate proteoglycans (HSPG), indicating that endocytosis is likely the main uptake pathway for both chimeric peptide-PMO conjugates. Collectively, our data demonstrate that peptide orientation in chimeric peptides is an important parameter that determines cellular uptake and activity when conjugated directly to oligonucleotides. These observations provide insight into the design of improved cell targeting compounds for future therapeutics studies.Molecular Therapy-Nucleic Acids (2013) 2, e124; doi:10.1038/mtna.2013

Context Dependent Effects of Chimeric Peptide Morpholino Conjugates Contribute to Dystrophin Exon-skipping Efficiency

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HaiFang Yin

2013-01-01

Full Text Available We have recently reported that cell-penetrating peptides (CPPs and novel chimeric peptides containing CPP (referred as B peptide and muscle-targeting peptide (referred as MSP motifs significantly improve the systemic exon-skipping activity of morpholino phosphorodiamidate oligomers (PMOs in dystrophin-deficient mdx mice. In the present study, the general mechanistic significance of the chimeric peptide configuration on the activity and tissue uptake of peptide conjugated PMOs in vivo was investigated. Four additional chimeric peptide-PMO conjugates including newly identified peptide 9 (B-9-PMO and 9-B-PMO and control peptide 3 (B-3-PMO and 3-B-PMO were tested in mdx mice. Immunohistochemical staining, RT-PCR and western blot results indicated that B-9-PMO induced significantly higher level of exon skipping and dystrophin restoration than its counterpart (9-B-PMO, further corroborating the notion that the activity of chimeric peptide-PMO conjugates is dependent on relative position of the tissue-targeting peptide motif within the chimeric peptide with respect to PMOs. Subsequent mechanistic studies showed that enhanced cellular uptake of B-MSP-PMO into muscle cells leads to increased exon-skipping activity in comparison with MSP-B-PMO. Surprisingly, further evidence showed that the uptake of chimeric peptide-PMO conjugates of both orientations (B-MSP-PMO and MSP-B-PMO was ATP- and temperature-dependent and also partially mediated by heparan sulfate proteoglycans (HSPG, indicating that endocytosis is likely the main uptake pathway for both chimeric peptide-PMO conjugates. Collectively, our data demonstrate that peptide orientation in chimeric peptides is an important parameter that determines cellular uptake and activity when conjugated directly to oligonucleotides. These observations provide insight into the design of improved cell targeting compounds for future therapeutics studies.

A duchenne muscular dystrophy gene hot spot mutation in dystrophin-deficient cavalier king charles spaniels is amenable to exon 51 skipping.

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Gemma L Walmsley

2010-01-01

Full Text Available Duchenne muscular dystrophy (DMD, which afflicts 1 in 3500 boys, is one of the most common genetic disorders of children. This fatal degenerative condition is caused by an absence or deficiency of dystrophin in striated muscle. Most affected patients have inherited or spontaneous deletions in the dystrophin gene that disrupt the reading frame resulting in unstable truncated products. For these patients, restoration of the reading frame via antisense oligonucleotide-mediated exon skipping is a promising therapeutic approach. The major DMD deletion "hot spot" is found between exons 45 and 53, and skipping exon 51 in particular is predicted to ameliorate the dystrophic phenotype in the greatest number of patients. Currently the mdx mouse is the most widely used animal model of DMD, although its mild phenotype limits its suitability in clinical trials. The Golden Retriever muscular dystrophy (GRMD model has a severe phenotype, but due to its large size, is expensive to use. Both these models have mutations in regions of the dystrophin gene distant from the commonly mutated DMD "hot spot".Here we describe the severe phenotype, histopathological findings, and molecular analysis of Cavalier King Charles Spaniels with dystrophin-deficient muscular dystrophy (CKCS-MD. The dogs harbour a missense mutation in the 5' donor splice site of exon 50 that results in deletion of exon 50 in mRNA transcripts and a predicted premature truncation of the translated protein. Antisense oligonucleotide-mediated skipping of exon 51 in cultured myoblasts from an affected dog restored the reading frame and protein expression.Given the small size of the breed, the amiable temperament and the nature of the mutation, we propose that CKCS-MD is a valuable new model for clinical trials of antisense oligonucleotide-induced exon skipping and other therapeutic approaches for DMD.

Identification of a novel first exon in the human dystrophin gene and of a new promoter located more than 500 kb upstream of the nearest known promoter

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Yanagawa, H.; Nishio, H.; Takeshima, Y. [Kobe Univ. School of Medicine (Japan)] [and others

1994-09-01

The dystrophin gene, which is muted in patients with Duchenne and Becker muscular dystrophies, is the largest known human gene. Five alternative promoters have been characterized until now. Here we show that a novel dystrophin isoform with a different first exon can be produced through transcription initiation at a previously-unidentified alternative promoter. The case study presented is that of patient with Duchenne muscular dystrophy who had a deletion extending from 5{prime} end of the dystrophin gene to exon 2, including all promoters previously mapped in the 5{prime} part of the gene. Transcripts from lymphoblastoid cells were found to contain sequences corresponding to exon 3, indicating the presence of new promoter upstream of this exon. The nucleotide sequence of amplified cDNA corresponding to the 5{prime} end of the new transcript indicated that the 5{prime} end of exon 3 was extended by 9 codons, only the last (most 3{prime}) of which codes for methionine. The genomic nucleotide sequence upstream from the new exon, as determined using inverse polymerase chain reaction, revealed the presence of sequences similar to a TATA box, an octamer motif and an MEF-2 element. The identified promoter/exon did not map to intron 2, as might have been expected, but to a position more than 500 kb upstream of the most 5{prime} of the previously-identified promoters, thereby adding 500 kb to the dystrophin gene. The sequence of part of the new promoter region is very similar to that of certain medium reiteration frequency repetitive sequences. These findings may help us understand the molecular evolution of the dystrophin gene.

Neuronal differentiation modulates the dystrophin Dp71d binding to the nuclear matrix

International Nuclear Information System (INIS)

Rodriguez-Munoz, Rafael; Villarreal-Silva, Marcela; Gonzalez-Ramirez, Ricardo; Garcia-Sierra, Francisco; Mondragon, Monica; Mondragon, Ricardo; Cerna, Joel; Cisneros, Bulmaro

2008-01-01

The function of dystrophin Dp71 in neuronal cells remains unknown. To approach this issue, we have selected the PC12 neuronal cell line. These cells express both a Dp71f cytoplasmic variant and a Dp71d nuclear isoform. In this study, we demonstrated by electron and confocal microscopy analyses of in situ nuclear matrices and Western blotting evaluation of cell extracts that Dp71d associates with the nuclear matrix. Interestingly, this binding is modulated during NGF-induced neuronal differentiation of PC12 cells with a twofold increment in the differentiated cells, compared to control cells. Also, distribution of Dp71d along the periphery of the nuclear matrix observed in the undifferentiated cells is replaced by intense fluorescent foci localized in Center of the nucleoskeletal structure. In summary, we revealed that Dp71d is a dynamic component of nuclear matrix that might participate in the nuclear modeling occurring during neuronal differentiation

Sarcospan integration into laminin-binding adhesion complexes that ameliorate muscular dystrophy requires utrophin and α7 integrin

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Marshall, Jamie L.; Oh, Jennifer; Chou, Eric; Lee, Joy A.; Holmberg, Johan; Burkin, Dean J.; Crosbie-Watson, Rachelle H.

2015-01-01

Duchenne muscular dystrophy (DMD) is caused by mutations in the dystrophin gene that result in loss of the dystrophin–glycoprotein complex, a laminin receptor that connects the myofiber to its surrounding extracellular matrix. Utrophin, a dystrophin ortholog that is normally localized to the neuromuscular junction, is naturally upregulated in DMD muscle, which partially compensates for the loss of dystrophin. Transgenic overexpression of utrophin causes broad sarcolemma localization of utrophin, restoration of laminin binding and amelioration of disease in the mdx mouse model of DMD. We previously demonstrated that overexpression of sarcospan, a dystrophin- and utrophin-binding protein, ameliorates mdx muscular dystrophy. Sarcospan boosts levels of utrophin to therapeutic levels at the sarcolemma, where attachment to laminin is restored. However, understanding the compensatory mechanism is complicated by concomitant upregulation of α7β1 integrin, which also binds laminin. Similar to the effects of utrophin, transgenic overexpression of α7 integrin prevents DMD disease in mice and is accompanied by increased abundance of utrophin around the extra-synaptic sarcolemma. In order to investigate the mechanisms underlying sarcospan ‘rescue’ of muscular dystrophy, we created double-knockout mice to test the contributions of utrophin or α7 integrin. We show that sarcospan-mediated amelioration of muscular dystrophy in DMD mice is dependent on the presence of both utrophin and α7β1 integrin, even when they are individually expressed at therapeutic levels. Furthermore, we found that association of sarcospan into laminin-binding complexes is dependent on utrophin and α7β1 integrin. PMID:25504048

Context Dependent Effects of Chimeric Peptide Morpholino Conjugates Contribute to Dystrophin Exon-skipping Efficiency

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HaiFang Yin; Prisca Boisguerin; Hong M Moulton; Corinne Betts; Yiqi Seow; Jordan Boutilier; Qingsong Wang; Anthony Walsh; Bernard Lebleu; Matthew JA Wood

2013-01-01

We have recently reported that cell-penetrating peptides (CPPs) and novel chimeric peptides containing CPP (referred as B peptide) and muscle-targeting peptide (referred as MSP) motifs significantly improve the systemic exon-skipping activity of morpholino phosphorodiamidate oligomers (PMOs) in dystrophin-deficient mdx mice. In the present study, the general mechanistic significance of the chimeric peptide configuration on the activity and tissue uptake of peptide conjugated PMOs in vivo was ...

Dystrophin-deficient dogs with reduced myostatin have unequal muscle growth and greater joint contractures.

Science.gov (United States)

Kornegay, Joe N; Bogan, Daniel J; Bogan, Janet R; Dow, Jennifer L; Wang, Jiahui; Fan, Zheng; Liu, Naili; Warsing, Leigh C; Grange, Robert W; Ahn, Mihye; Balog-Alvarez, Cynthia J; Cotten, Steven W; Willis, Monte S; Brinkmeyer-Langford, Candice; Zhu, Hongtu; Palandra, Joe; Morris, Carl A; Styner, Martin A; Wagner, Kathryn R

2016-01-01

Myostatin (Mstn) is a negative regulator of muscle growth whose inhibition promotes muscle growth and regeneration. Dystrophin-deficient mdx mice in which myostatin is knocked out or inhibited postnatally have a less severe phenotype with greater total mass and strength and less fibrosis and fatty replacement of muscles than mdx mice with wild-type myostatin expression. Dogs with golden retriever muscular dystrophy (GRMD) have previously been noted to have increased muscle mass and reduced fibrosis after systemic postnatal myostatin inhibition. Based partly on these results, myostatin inhibitors are in development for use in human muscular dystrophies. However, persisting concerns regarding the effects of long-term and profound myostatin inhibition will not be easily or imminently answered in clinical trials. To address these concerns, we developed a canine (GRippet) model by crossbreeding dystrophin-deficient GRMD dogs with Mstn-heterozygous (Mstn (+/-)) whippets. A total of four GRippets (dystrophic and Mstn (+/-)), three GRMD (dystrophic and Mstn wild-type) dogs, and three non-dystrophic controls from two litters were evaluated. Myostatin messenger ribonucleic acid (mRNA) and protein levels were downregulated in both GRMD and GRippet dogs. GRippets had more severe postural changes and larger (more restricted) maximal joint flexion angles, apparently due to further exaggeration of disproportionate effects on muscle size. Flexors such as the cranial sartorius were more hypertrophied on magnetic resonance imaging (MRI) in the GRippets, while extensors, including the quadriceps femoris, underwent greater atrophy. Myostatin protein levels negatively correlated with relative cranial sartorius muscle cross-sectional area on MRI, supporting a role in disproportionate muscle size. Activin receptor type IIB (ActRIIB) expression was higher in dystrophic versus control dogs, consistent with physiologic feedback between myostatin and ActRIIB. However, there was no

A novel point mutation (G[sup [minus]1] to T) in a 5[prime] splice donor site of intron 13 of the dystrophin gene results in exon skipping and is responsible for Becker Muscular Dystrophy

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Hagiwara, Yoko; Nishio, Hisahide; Kitoh, Yoshihiko; Takeshima, Yasuhiro; Narita, Naoko; Wada, Hiroko; Yokoyama, Mitsuhiro; Nakamura, Hajime; Matsuo, Masafumi (Kobe Univ. School of Medicine (Japan))

1994-01-01

The mutations in one-third of Duchenne and Becker muscular dystrophy patients remain unknown, as they do not involve gross rearrangements of the dystrophin gene. The authors now report a defect in the splicing of precursor mRNA (pre-mRNA), resulting from a maternally inherited mutation of the dystrophin gene in a patient with Becker muscular dystrophy. This defect results from a G-to-T transversion at the terminal nucleotide of exon 13, within the 5[prime] splice site of intron 13, and causes complete skipping of exon 13 during processing of dystrophin pre-mRNA. The predicted polypeptide encoded by the aberrant mRNA is a truncated dystrophin lacking 40 amino acids from the amino-proximal end of the rod domain. This is the first report of an intraexon point mutation that completely inactivates a 5[prime] splice donor site in dystrophin pre-mRNA. Analysis of the genomic context of the G[sup [minus]1]-to-T mutation at the 5[prime] splice site supports the exon-definition model of pre-mRNA splicing and contributes to the understanding of splice-site selection. 48 refs., 5 figs.

MLPA based detection of mutations in the dystrophin gene of 180 Polish families with Duchenne/Becker muscular dystrophy.

Science.gov (United States)

Zimowski, Janusz G; Massalska, Diana; Holding, Mariola; Jadczak, Sylwia; Fidziańska, Elżbieta; Lusakowska, Anna; Kostera-Pruszczyk, Anna; Kamińska, Anna; Zaremba, Jacek

2014-01-01

Duchenne/Becker muscular dystrophy (DMD/BMD) is a recessive, X-linked disorder caused by a mutation in the dystrophin gene. Deletions account for approximately 60-65% of mutations, duplications for 5-10%. The remaining cases are mainly point mutations. According to Monaco theory clinical form of the disease depends on maintaining or disrupting the reading frame. The purpose of the study was to determine frequency and location of deletions and duplications in the dystrophin gene, to determine the compliance between maintaining/disrupting the reading frame and clinical form of the disease and to check the effectiveness of MLPA (multiplex ligation-dependent probe amplification) in the detection of these mutations in hemizygous patients and heterozygous female carriers. The material is composed of combined results of molecular diagnosis carried out in years 2009-2012 in 180 unrelated patients referred with the diagnosis of DMD/BMD tested by use of MLPA. We identified 110 deletions, 22 duplication (in one patient two different duplications were detected) and 2 point mutations. Deletions involved mainly exons 45-54 and 3-21, whereas most duplications involved exons 3-18. The compliance with Monaco theory was 95% for deletions and 76% for duplications. Most of mutations in the dystrophin gene were localized in the hot spots - different for deletions and duplications. MLPA enabled their quick identification, exact localization and determination whether or not they maintained or disrupted the reading frame. MLPA was also effective in detection of deletions and duplications in female carriers. Copyright © 2014 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Electroporation Enhanced Effect of Dystrophin Splice Switching PNA Oligomers in Normal and Dystrophic Muscle

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Camilla Brolin

2015-01-01

Full Text Available Peptide nucleic acid (PNA is a synthetic DNA mimic that has shown potential for discovery of novel splice switching antisense drugs. However, in vivo cellular delivery has been a limiting factor for development, and only few successful studies have been reported. As a possible modality for improvement of in vivo cellular availability, we have investigated the effect of electrotransfer upon intramuscular (i.m. PNA administration in vivo. Antisense PNA targeting exon 23 of the murine dystrophin gene was administered by i.m. injection to the tibialis anterior (TA muscle of normal NMRI and dystrophic mdx mice with or without electroporation. At low, single PNA doses (1.5, 3, or 10 µg/TA, electroporation augmented the antisense exon skipping induced by an unmodified PNA by twofold to fourfold in healthy mouse muscle with optimized electric parameters, measured after 7 days. The PNA splice switching was detected at the RNA level up to 4 weeks after a single-dose treatment. In dystrophic muscles of the MDX mouse, electroporation increased the number of dystrophin-positive fibers about 2.5-fold at 2 weeks after a single PNA administration compared to injection only. In conclusion, we find that electroporation can enhance PNA antisense effects in muscle tissue.

Fetal skeletal muscle progenitors have regenerative capacity after intramuscular engraftment in dystrophin deficient mice.

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Hiroshi Sakai

Full Text Available Muscle satellite cells (SCs are stem cells that reside in skeletal muscles and contribute to regeneration upon muscle injury. SCs arise from skeletal muscle progenitors expressing transcription factors Pax3 and/or Pax7 during embryogenesis in mice. However, it is unclear whether these fetal progenitors possess regenerative ability when transplanted in adult muscle. Here we address this question by investigating whether fetal skeletal muscle progenitors (FMPs isolated from Pax3(GFP/+ embryos have the capacity to regenerate muscle after engraftment into Dystrophin-deficient mice, a model of Duchenne muscular dystrophy. The capacity of FMPs to engraft and enter the myogenic program in regenerating muscle was compared with that of SCs derived from adult Pax3(GFP/+ mice. Transplanted FMPs contributed to the reconstitution of damaged myofibers in Dystrophin-deficient mice. However, despite FMPs and SCs having similar myogenic ability in culture, the regenerative ability of FMPs was less than that of SCs in vivo. FMPs that had activated MyoD engrafted more efficiently to regenerate myofibers than MyoD-negative FMPs. Transcriptome and surface marker analyses of these cells suggest the importance of myogenic priming for the efficient myogenic engraftment. Our findings suggest the regenerative capability of FMPs in the context of muscle repair and cell therapy for degenerative muscle disease.

Short (16-mer locked nucleic acid splice-switching oligonucleotides restore dystrophin production in Duchenne Muscular Dystrophy myotubes.

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Vanessa Borges Pires

Full Text Available Splice-switching antisense oligonucleotides (SSOs offer great potential for RNA-targeting therapies, and two SSO drugs have been recently approved for treating Duchenne Muscular Dystrophy (DMD and Spinal Muscular Atrophy (SMA. Despite promising results, new developments are still needed for more efficient chemistries and delivery systems. Locked nucleic acid (LNA is a chemically modified nucleic acid that presents several attractive properties, such as high melting temperature when bound to RNA, potent biological activity, high stability and low toxicity in vivo. Here, we designed a series of LNA-based SSOs complementary to two sequences of the human dystrophin exon 51 that are most evolutionary conserved and evaluated their ability to induce exon skipping upon transfection into myoblasts derived from a DMD patient. We show that 16-mers with 60% of LNA modification efficiently induce exon skipping and restore synthesis of a truncated dystrophin isoform that localizes to the plasma membrane of patient-derived myotubes differentiated in culture. In sum, this study underscores the value of short LNA-modified SSOs for therapeutic applications.

Quantitative analysis of the dystrophin gene by real-time PCR

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Maksimovic Nela

2012-01-01

Full Text Available Duchenne and Becker muscular dystrophy (DMD/BMD are severe X-linked neuromuscular disorders caused by mutations in the dystrophin gene. Our aim was to optimize a quantitative real-time PCR method based on SYBR® Green I chemistry for routine diagnostics of DMD/BMD deletion carriers. Twenty female relatives of DMD/BMD patients with previously detected partial gene deletions were studied. The relative quantity of the target exons was calculated by a comparative threshold cycle method (ΔΔCt. The carrier status of all subjects was successfully determined. The gene dosage ratio for non-carriers was 1.07±0.20, and for carriers 0.56±0.11. This assay proved to be simple, rapid, reliable and cost-effective.

Clinical and molecular characterization of a cohort of patients with novel nucleotide alterations of the Dystrophin gene detected by direct sequencing

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Corti Stefania

2011-03-01

Full Text Available Abstract Background Duchenne and Becker Muscular dystrophies (DMD/BMD are allelic disorders caused by mutations in the dystrophin gene, which encodes a sarcolemmal protein responsible for muscle integrity. Deletions and duplications account for approximately 75% of mutations in DMD and 85% in BMD. The implementation of techniques allowing complete gene sequencing has focused attention on small point mutations and other mechanisms underlying complex rearrangements. Methods We selected 47 patients (41 families; 35 DMD, 6 BMD without deletions and duplications in DMD gene (excluded by multiplex ligation-dependent probe amplification and multiplex polymerase chain reaction analysis. This cohort was investigated by systematic direct sequence analysis to study sequence variation. We focused our attention on rare mutational events which were further studied through transcript analysis. Results We identified 40 different nucleotide alterations in DMD gene and their clinical correlates; altogether, 16 mutations were novel. DMD probands carried 9 microinsertions/microdeletions, 19 nonsense mutations, and 7 splice-site mutations. BMD patients carried 2 nonsense mutations, 2 splice-site mutations, 1 missense substitution, and 1 single base insertion. The most frequent stop codon was TGA (n = 10 patients, followed by TAG (n = 7 and TAA (n = 4. We also analyzed the molecular mechanisms of five rare mutational events. They are two frame-shifting mutations in the DMD gene 3'end in BMD and three novel splicing defects: IVS42: c.6118-3C>A, which causes a leaky splice-site; c.9560A>G, which determines a cryptic splice-site activation and c.9564-426 T>G, which creates pseudoexon retention within IVS65. Conclusion The analysis of our patients' sample, carrying point mutations or complex rearrangements in DMD gene, contributes to the knowledge on phenotypic correlations in dystrophinopatic patients and can provide a better understanding of pre-mRNA maturation defects

Compensation for dystrophin-deficiency: ADAM12 overexpression in skeletal muscle results in increased alpha 7 integrin, utrophin and associated glycoproteins

DEFF Research Database (Denmark)

Moghadaszadeh, Behzad; Albrechtsen, Reidar; Guo, Ling T

2003-01-01

Mouse models for genetic diseases are among the most powerful tools available for developing and testing new treatment strategies. ADAM12 is a disintegrin and metalloprotease, previously demonstrated to significantly alleviate the pathology of mdx mice, a model for Duchenne muscular dystrophy...... in humans. More specifically ADAM12 appeared to prevent muscle cell necrosis in the mdx mice as evidenced by morphological analysis and by the reduced levels of serum creatine kinase. In the present study we demonstrated that ADAM12 may compensate for the dystrophin deficiency in mdx mice by increasing...... the expression and redistribution of several components of the muscle cell-adhesion complexes. First, we analyzed transgenic mice that overexpress ADAM12 and found mild myopathic changes and accelerated regeneration following acute injury. We then analyzed changes in gene-expression profiles in mdx/ADAM12...

Multiple species comparison of cardiac troponin T and dystrophin: unravelling the DNA behind dilated cardiomyopathy

OpenAIRE

England, Jennifer; Loughna, Siobhan; Rutland, Catrin S.

2017-01-01

Animals have frequently been used as models for human disorders and mutations. Following advances in genetic testing and treatment options, and the decreasing cost of these technologies in the clinic, mutations in both companion and commercial animals are now being investigated. A recent review highlighted the genes associated with both human and non-human dilated cardiomyopathy. Cardiac troponin T and dystrophin were observed to be associated with both human and turkey (troponin T) and canin...

Effective myotube formation in human adipose tissue-derived stem cells expressing dystrophin and myosin heavy chain by cellular fusion with mouse C2C12 myoblasts

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Eom, Young Woo [Cell Therapy and Tissue Engineering Center, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of); Biomedical Research Institute, Lifeliver Co., Ltd., Suwon (Korea, Republic of); Lee, Jong Eun; Yang, Mal Sook; Jang, In Keun; Kim, Hyo Eun; Lee, Doo Hoon; Kim, Young Jin [Biomedical Research Institute, Lifeliver Co., Ltd., Suwon (Korea, Republic of); Park, Won Jin [Dr. Park' s Aesthetic Clinic, Seoul (Korea, Republic of); Kong, Jee Hyun; Shim, Kwang Yong [Department of Hematology-Oncology, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of); Lee, Jong In, E-mail: oncochem@yonsei.ac.kr [Department of Hematology-Oncology, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of); Kim, Hyun Soo, E-mail: khsmd@unitel.co.kr [Department of Hematology-Oncology, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of)

2011-04-29

Highlights: {yields} hASCs were differentiated into skeletal muscle cells by treatment with 5-azacytidine, FGF-2, and the supernatant of cultured hASCs. {yields} Dystrophin and MyHC were expressed in late differentiation step by treatment with the supernatant of cultured hASCs. {yields} hASCs expressing dystrophin and MyHC contributed to myotube formation during co-culture with mouse myoblast C2C12 cells. -- Abstract: Stem cell therapy for muscular dystrophies requires stem cells that are able to participate in the formation of new muscle fibers. However, the differentiation steps that are the most critical for this process are not clear. We investigated the myogenic phases of human adipose tissue-derived stem cells (hASCs) step by step and the capability of myotube formation according to the differentiation phase by cellular fusion with mouse myoblast C2C12 cells. In hASCs treated with 5-azacytidine and fibroblast growth factor-2 (FGF-2) for 1 day, the early differentiation step to express MyoD and myogenin was induced by FGF-2 treatment for 6 days. Dystrophin and myosin heavy chain (MyHC) expression was induced by hASC conditioned medium in the late differentiation step. Myotubes were observed only in hASCs undergoing the late differentiation step by cellular fusion with C2C12 cells. In contrast, hASCs that were normal or in the early stage were not involved in myotube formation. Our results indicate that stem cells expressing dystrophin and MyHC are more suitable for myotube formation by co-culture with myoblasts than normal or early differentiated stem cells expressing MyoD and myogenin.

Effective myotube formation in human adipose tissue-derived stem cells expressing dystrophin and myosin heavy chain by cellular fusion with mouse C2C12 myoblasts

International Nuclear Information System (INIS)

Eom, Young Woo; Lee, Jong Eun; Yang, Mal Sook; Jang, In Keun; Kim, Hyo Eun; Lee, Doo Hoon; Kim, Young Jin; Park, Won Jin; Kong, Jee Hyun; Shim, Kwang Yong; Lee, Jong In; Kim, Hyun Soo

2011-01-01

Highlights: → hASCs were differentiated into skeletal muscle cells by treatment with 5-azacytidine, FGF-2, and the supernatant of cultured hASCs. → Dystrophin and MyHC were expressed in late differentiation step by treatment with the supernatant of cultured hASCs. → hASCs expressing dystrophin and MyHC contributed to myotube formation during co-culture with mouse myoblast C2C12 cells. -- Abstract: Stem cell therapy for muscular dystrophies requires stem cells that are able to participate in the formation of new muscle fibers. However, the differentiation steps that are the most critical for this process are not clear. We investigated the myogenic phases of human adipose tissue-derived stem cells (hASCs) step by step and the capability of myotube formation according to the differentiation phase by cellular fusion with mouse myoblast C2C12 cells. In hASCs treated with 5-azacytidine and fibroblast growth factor-2 (FGF-2) for 1 day, the early differentiation step to express MyoD and myogenin was induced by FGF-2 treatment for 6 days. Dystrophin and myosin heavy chain (MyHC) expression was induced by hASC conditioned medium in the late differentiation step. Myotubes were observed only in hASCs undergoing the late differentiation step by cellular fusion with C2C12 cells. In contrast, hASCs that were normal or in the early stage were not involved in myotube formation. Our results indicate that stem cells expressing dystrophin and MyHC are more suitable for myotube formation by co-culture with myoblasts than normal or early differentiated stem cells expressing MyoD and myogenin.

A BanI RFLP at a deletion hotspot in the human dystrophin gene

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Read, A P; Mountford, R [St. Mary' s Hospital, Manchester (England)

1990-01-25

Cf56a is a 0.9 kb EcoRI fragment of dystrophin cDNA in pUC13. Cf56a is identical to Kunkel's cDNA probe 8. Constant bands of 14.4, 11.0, 8.1, 6.2 and 1.3 kb correspond to exons I, N, L, N and K respectively. The polymorphic band is exon J (exon 48, 1.2+3.9 kb HindIII bands). This exon is deleted in 25% of all Duchenne/Becker dystrophy boys. Therefore this RFLP is useful for determining carrier status of at-risk females by showing heterozygosity or apparent non-maternity.

Long-Term Efficacy of Systemic Multiexon Skipping Targeting Dystrophin Exons 45–55 With a Cocktail of Vivo-Morpholinos in Mdx52 Mice

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Yusuke Echigoya

2015-01-01

Full Text Available Antisense-mediated exon skipping, which can restore the reading frame, is a most promising therapeutic approach for Duchenne muscular dystrophy. Remaining challenges include the limited applicability to patients and unclear function of truncated dystrophin proteins. Multiexon skipping targeting exons 45–55 at the mutation hotspot of the dystrophin gene could overcome both of these challenges. Previously, we described the feasibility of exons 45–55 skipping with a cocktail of Vivo-Morpholinos in vivo; however, the long-term efficacy and safety of Vivo-Morpholinos remains to be determined. In this study, we examined the efficacy and toxicity of exons 45–55 skipping by intravenous injections of 6 mg/kg 10-Vivo-Morpholino cocktail (0.6 mg/kg each vPMO every 2 weeks for 18 weeks to dystrophic exon-52 knockout (mdx52 mice. Systemic skipping of the entire exons 45–55 region was induced, and the Western blot analysis exhibited the restoration of 5–27% of normal levels of dystrophin protein in skeletal muscles, accompanied by improvements in histopathology and muscle strength. No obvious immune response and renal and hepatic toxicity were detected at the end-point of the treatment. We demonstrate our new regimen with the 10-Vivo-Morpholino cocktail is effective and safe for long-term repeated systemic administration in the dystrophic mouse model.

Eosinophilia of dystrophin-deficient muscle is promoted by perforin-mediated cytotoxicity by T cell effectors

Science.gov (United States)

Cai, B.; Spencer, M. J.; Nakamura, G.; Tseng-Ong, L.; Tidball, J. G.

2000-01-01

Previous investigations have shown that cytotoxic T lymphocytes (CTLs) contribute to muscle pathology in the dystrophin-null mutant mouse (mdx) model of Duchenne muscular dystrophy through perforin-dependent and perforin-independent mechanisms. We have assessed whether the CTL-mediated pathology includes the promotion of eosinophilia in dystrophic muscle, and thereby provides a secondary mechanism through which CTLs contribute to muscular dystrophy. Quantitative immunohistochemistry confirmed that eosinophilia is a component of the mdx dystrophy. In addition, electron microscopic observations show that eosinophils traverse the basement membrane of mdx muscle fibers and display sites of close apposition of eosinophil and muscle membranes. The close membrane apposition is characterized by impingement of eosinophilic rods of major basic protein into the muscle cell membrane. Transfer of mdx splenocytes and mdx muscle extracts to irradiated C57 mice by intraperitoneal injection resulted in muscle eosinophilia in the recipient mice. Double-mutant mice lacking dystrophin and perforin showed less eosinophilia than was displayed by mdx mice that expressed perforin. Finally, administration of prednisolone, which has been shown previously to reduce the concentration of CTLs in dystrophic muscle, produced a significant reduction in eosinophilia. These findings indicate that eosinophilia is a component of the mdx pathology that is promoted by perforin-dependent cytotoxicity of effector T cells. However, some eosinophilia of mdx muscle is independent of perforin-mediated processes.

Dual Myostatin and Dystrophin Exon Skipping by Morpholino Nucleic Acid Oligomers Conjugated to a Cell-penetrating Peptide Is a Promising Therapeutic Strategy for the Treatment of Duchenne Muscular Dystrophy

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Alberto Malerba

2012-01-01

Full Text Available The knockdown of myostatin, a negative regulator of skeletal muscle mass may have important implications in disease conditions accompanied by muscle mass loss like cancer, HIV/AIDS, sarcopenia, muscle atrophy, and Duchenne muscular dystrophy (DMD. In DMD patients, where major muscle loss has occurred due to a lack of dystrophin, the therapeutic restoration of dystrophin expression alone in older patients may not be sufficient to restore the functionality of the muscles. We recently demonstrated that phosphorodiamidate morpholino oligomers (PMOs can be used to re-direct myostatin splicing and promote the expression of an out-of-frame transcript so reducing the amount of the synthesized myostatin protein. Furthermore, the systemic administration of the same PMO conjugated to an octaguanidine moiety (Vivo-PMO led to a significant increase in the mass of soleus muscle of treated mice. Here, we have further optimized the use of Vivo-PMO in normal mice and also tested the efficacy of the same PMO conjugated to an arginine-rich cell-penetrating peptide (B-PMO. Similar experiments conducted in mdx dystrophic mice showed that B-PMO targeting myostatin is able to significantly increase the tibialis anterior (TA muscle weight and when coadministered with a B-PMO targeting the dystrophin exon 23, it does not have a detrimental interaction. This study confirms that myostatin knockdown by exon skipping is a potential therapeutic strategy to counteract muscle wasting conditions and dual myostatin and dystrophin skipping has potential as a therapy for DMD.

Haplotypes in the Dystrophin DNA Segment Point to a Mosaic Origin of Modern Human Diversity

OpenAIRE

Ziętkiewicz, Ewa; Yotova, Vania; Gehl, Dominik; Wambach, Tina; Arrieta, Isabel; Batzer, Mark; Cole, David E.C.; Hechtman, Peter; Kaplan, Feige; Modiano, David; Moisan, Jean-Paul; Michalski, Roman; Labuda, Damian

2003-01-01

Although Africa has played a central role in human evolutionary history, certain studies have suggested that not all contemporary human genetic diversity is of recent African origin. We investigated 35 simple polymorphic sites and one Tn microsatellite in an 8-kb segment of the dystrophin gene. We found 86 haplotypes in 1,343 chromosomes from around the world. Although a classical out-of-Africa topology was observed in trees based on the variant frequencies, the tree of haplotype sequences re...

Somatic mosaicism of a point mutation in the dystrophin gene in a patient presenting with an asymmetrical muscle weakness and contractures

NARCIS (Netherlands)

Helderman-van den Enden, A. T. J. M.; Ginjaar, H. B.; Kneppers, A. L. J.; Bakker, E.; Breuning, M. H.; de Visser, M.

2003-01-01

We describe a patient with somatic mosaicism of a point mutation in the dystrophin gene causing benign muscular dystrophy with an unusual asymmetrical distribution of muscle weakness and contractures. To our knowledge this is the first patient with asymmetrical weakness and contractures in an

100-fold but not 50-fold dystrophin overexpression aggravates electrocardiographic defects in the mdx model of Duchenne muscular dystrophy

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Yongping Yue

2016-01-01

Full Text Available Dystrophin gene replacement holds the promise of treating Duchenne muscular dystrophy. Supraphysiological expression is a concern for all gene therapy studies. In the case of Duchenne muscular dystrophy, Chamberlain and colleagues found that 50-fold overexpression did not cause deleterious side effect in skeletal muscle. To determine whether excessive dystrophin expression in the heart is safe, we studied two lines of transgenic mdx mice that selectively expressed a therapeutic minidystrophin gene in the heart at 50-fold and 100-fold of the normal levels. In the line with 50-fold overexpression, minidystrophin showed sarcolemmal localization and electrocardiogram abnormalities were corrected. However, in the line with 100-fold overexpression, we not only detected sarcolemmal minidystrophin expression but also observed accumulation of minidystrophin vesicles in the sarcoplasm. Excessive minidystrophin expression did not correct tachycardia, a characteristic feature of Duchenne muscular dystrophy. Importantly, several electrocardiogram parameters (QT interval, QRS duration and the cardiomyopathy index became worse than that of mdx mice. Our data suggests that the mouse heart can tolerate 50-fold minidystrophin overexpression, but 100-fold overexpression leads to cardiac toxicity.

Modulation of Protein Quality Control and Proteasome to Autophagy Switch in Immortalized Myoblasts from Duchenne Muscular Dystrophy Patients

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Marion Wattin

2018-01-01

Full Text Available The maintenance of proteome integrity is of primary importance in post-mitotic tissues such as muscle cells; thus, protein quality control mechanisms must be carefully regulated to ensure their optimal efficiency, a failure of these processes being associated with various muscular disorders. Duchenne muscular dystrophy (DMD is one of the most common and severe forms of muscular dystrophies and is caused by mutations in the dystrophin gene. Protein quality control modulations have been diversely observed in degenerating muscles of patients suffering from DMD or in animal models of the disease. In this study, we investigated whether modulations of protein quality control mechanisms already pre-exist in undifferentiated myoblasts originating from DMD patients. We report for the first time that the absence of dystrophin in human myoblasts is associated with protein aggregation stress characterized by an increase of protein aggregates. This stress is combined with BAG1 to BAG3 switch, NFκB activation and up-regulation of BAG3/HSPB8 complexes that ensure preferential routing of misfolded/aggregated proteins to autophagy rather than to deficient 26S proteasome. In this context, restoration of pre-existing alterations of protein quality control processes might represent an alternative strategy for DMD therapies.

A BanI RFLP at a deletion hotspot in the human dystrophin gene

Energy Technology Data Exchange (ETDEWEB)

Read, A.P.; Mountford, R. (St. Mary' s Hospital, Manchester (England))

1990-01-25

Cf56a is a 0.9 kb EcoRI fragment of dystrophin cDNA in pUC13. Cf56a is identical to Kunkel's cDNA probe 8. Constant bands of 14.4, 11.0, 8.1, 6.2 and 1.3 kb correspond to exons I, N, L, N and K respectively. The polymorphic band is exon J (exon 48, 1.2+3.9 kb HindIII bands). This exon is deleted in 25% of all Duchenne/Becker dystrophy boys. Therefore this RFLP is useful for determining carrier status of at-risk females by showing heterozygosity or apparent non-maternity.

Distal mdx muscle groups exhibiting up-regulation of utrophin and rescue of dystrophin-associated glycoproteins exemplify a protected phenotype in muscular dystrophy

Science.gov (United States)

Dowling, Paul; Culligan, Kevin; Ohlendieck, Kay

2002-02-01

Unique unaffected skeletal muscle fibres, unlike necrotic torso and limb muscles, may pave the way for a more detailed understanding of the molecular pathogenesis of inherited neuromuscular disorders and help to develop new treatment strategies for muscular dystrophies. The sparing of extraocular muscle in Duchenne muscular dystrophy is mostly attributed to the special protective properties of extremely fast-twitching small-diameter fibres, but here we show that distal muscles also represent a particular phenotype that is more resistant to necrosis. Immunoblot analysis of membranes isolated from the well established dystrophic animal model mdx shows that, in contrast to dystrophic limb muscles, the toe musculature exhibits an up-regulation of the autosomal dystrophin homologue utrophin and a concomitant rescue of dystrophin-associated glycoproteins. Thus distal mdx muscle groups provide a cellular system that naturally avoids myofibre degeneration which might be useful in the search for naturally occurring compensatory mechanisms in inherited skeletal muscle diseases.

Sarcospan: a small protein with large potential for Duchenne muscular dystrophy

Science.gov (United States)

2013-01-01

Purification of the proteins associated with dystrophin, the gene product responsible for Duchenne muscular dystrophy, led to the discovery of the dystrophin-glycoprotein complex. Sarcospan, a 25-kDa transmembrane protein, was the last component to be identified and its function in skeletal muscle has been elusive. This review will focus on progress over the last decade revealing that sarcospan is an important regulator of muscle cell adhesion, strength, and regeneration. Investigations using several transgenic mouse models demonstrate that overexpression of sarcospan in the mouse model for Duchenne muscular dystrophy ameliorates pathology and restores muscle cell binding to laminin. Sarcospan improves cell surface expression of the dystrophin- and utrophin-glycoprotein complexes as well as α7β1 integrin, which are the three major laminin-binding complexes in muscle. Utrophin and α7β1 integrin compensate for the loss of dystrophin and the finding that sarcospan increases their abundance at the extra-synaptic sarcolemma supports the use of sarcospan as a therapeutic target. Newly discovered phenotypes in sarcospan-deficient mice, including a reduction in specific force output and increased drop in force in the diaphragm muscle, result from decreased utrophin and dystrophin expression and further reveal sarcospan’s role in determining abundance of these complexes. Dystrophin protein levels and the specific force output of the diaphragm muscle are further reduced upon genetic removal of α7 integrin (Itga7) in SSPN-deficient mice, demonstrating that interactions between integrin and sarcospan are critical for maintenance of the dystrophin-glycoprotein complex and force production of the diaphragm muscle. Sarcospan is a major regulator of Akt signaling pathways and sarcospan-deficiency significantly impairs muscle regeneration, a process that is dependent on Akt activation. Intriguingly, sarcospan regulates glycosylation of a specific subpopulation of �

Missense mutation Lys18Asn in dystrophin that triggers X-linked dilated cardiomyopathy decreases protein stability, increases protein unfolding, and perturbs protein structure, but does not affect protein function.

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Surinder M Singh

Full Text Available Genetic mutations in a vital muscle protein dystrophin trigger X-linked dilated cardiomyopathy (XLDCM. However, disease mechanisms at the fundamental protein level are not understood. Such molecular knowledge is essential for developing therapies for XLDCM. Our main objective is to understand the effect of disease-causing mutations on the structure and function of dystrophin. This study is on a missense mutation K18N. The K18N mutation occurs in the N-terminal actin binding domain (N-ABD. We created and expressed the wild-type (WT N-ABD and its K18N mutant, and purified to homogeneity. Reversible folding experiments demonstrated that both mutant and WT did not aggregate upon refolding. Mutation did not affect the protein's overall secondary structure, as indicated by no changes in circular dichroism of the protein. However, the mutant is thermodynamically less stable than the WT (denaturant melts, and unfolds faster than the WT (stopped-flow kinetics. Despite having global secondary structure similar to that of the WT, mutant showed significant local structural changes at many amino acids when compared with the WT (heteronuclear NMR experiments. These structural changes indicate that the effect of mutation is propagated over long distances in the protein structure. Contrary to these structural and stability changes, the mutant had no significant effect on the actin-binding function as evident from co-sedimentation and depolymerization assays. These results summarize that the K18N mutation decreases thermodynamic stability, accelerates unfolding, perturbs protein structure, but does not affect the function. Therefore, K18N is a stability defect rather than a functional defect. Decrease in stability and increase in unfolding decrease the net population of dystrophin molecules available for function, which might trigger XLDCM. Consistently, XLDCM patients have decreased levels of dystrophin in cardiac muscle.

Voluntary wheel running in dystrophin-deficient (mdx) mice: Relationships between exercise parameters and exacerbation of the dystrophic phenotype

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Smythe, Gayle M; White, Jason D

2012-01-01

Voluntary wheel running can potentially be used to exacerbate the disease phenotype in dystrophin-deficient mdx mice. While it has been established that voluntary wheel running is highly variable between individuals, the key parameters of wheel running that impact the most on muscle pathology have not been examined in detail. We conducted a 2-week test of voluntary wheel running by mdx mice and the impact of wheel running on disease pathology. There was significant individual variation in the...

Sensitivity and Frequencies of Dystrophin Gene Mutations in Thai DMD/BMD Patients As Detected by Multiplex PCR

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Thanyachai Sura

2008-01-01

Full Text Available Background: Duchenne muscular dystrophy (DMD, a lethal X-linked disease affecting 1 in 3500 male births, and its more benign variant, Becker muscular dystrophy (BMD, are caused by mutations in the dystrophin gene. Because of its large size, analysing the whole gene is impractical. Methods have been developed to detect the commonest mutations i.e. the deletions of the exons. Although these tests are highly specific, their sensitivity is inherently limited by the prevalence of deletions, which differs among different populations.

Exonization of an Intronic LINE-1 Element Causing Becker Muscular Dystrophy as a Novel Mutational Mechanism in Dystrophin Gene.

Science.gov (United States)

Gonçalves, Ana; Oliveira, Jorge; Coelho, Teresa; Taipa, Ricardo; Melo-Pires, Manuel; Sousa, Mário; Santos, Rosário

2017-10-03

A broad mutational spectrum in the dystrophin ( DMD ) gene, from large deletions/duplications to point mutations, causes Duchenne/Becker muscular dystrophy (D/BMD). Comprehensive genotyping is particularly relevant considering the mutation-centered therapies for dystrophinopathies. We report the genetic characterization of a patient with disease onset at age 13 years, elevated creatine kinase levels and reduced dystrophin labeling, where multiplex-ligation probe amplification (MLPA) and genomic sequencing failed to detect pathogenic variants. Bioinformatic, transcriptomic (real time PCR, RT-PCR), and genomic approaches (Southern blot, long-range PCR, and single molecule real-time sequencing) were used to characterize the mutation. An aberrant transcript was identified, containing a 103-nucleotide insertion between exons 51 and 52, with no similarity with the DMD gene. This corresponded to the partial exonization of a long interspersed nuclear element (LINE-1), disrupting the open reading frame. Further characterization identified a complete LINE-1 (~6 kb with typical hallmarks) deeply inserted in intron 51. Haplotyping and segregation analysis demonstrated that the mutation had a de novo origin. Besides underscoring the importance of mRNA studies in genetically unsolved cases, this is the first report of a disease-causing fully intronic LINE-1 element in DMD , adding to the diversity of mutational events that give rise to D/BMD.

Exonization of an Intronic LINE-1 Element Causing Becker Muscular Dystrophy as a Novel Mutational Mechanism in Dystrophin Gene

Science.gov (United States)

Gonçalves, Ana; Coelho, Teresa; Melo-Pires, Manuel; Sousa, Mário

2017-01-01

A broad mutational spectrum in the dystrophin (DMD) gene, from large deletions/duplications to point mutations, causes Duchenne/Becker muscular dystrophy (D/BMD). Comprehensive genotyping is particularly relevant considering the mutation-centered therapies for dystrophinopathies. We report the genetic characterization of a patient with disease onset at age 13 years, elevated creatine kinase levels and reduced dystrophin labeling, where multiplex-ligation probe amplification (MLPA) and genomic sequencing failed to detect pathogenic variants. Bioinformatic, transcriptomic (real time PCR, RT-PCR), and genomic approaches (Southern blot, long-range PCR, and single molecule real-time sequencing) were used to characterize the mutation. An aberrant transcript was identified, containing a 103-nucleotide insertion between exons 51 and 52, with no similarity with the DMD gene. This corresponded to the partial exonization of a long interspersed nuclear element (LINE-1), disrupting the open reading frame. Further characterization identified a complete LINE-1 (~6 kb with typical hallmarks) deeply inserted in intron 51. Haplotyping and segregation analysis demonstrated that the mutation had a de novo origin. Besides underscoring the importance of mRNA studies in genetically unsolved cases, this is the first report of a disease-causing fully intronic LINE-1 element in DMD, adding to the diversity of mutational events that give rise to D/BMD. PMID:28972564

Somatodendritic and excitatory postsynaptic distribution of neuron-type dystrophin isoform, Dp40, in hippocampal neurons

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Fujimoto, Takahiro; Itoh, Kyoko, E-mail: kxi14@koto.kpu-m.ac.jp; Yaoi, Takeshi; Fushiki, Shinji

2014-09-12

Highlights: • Identification of dystrophin (Dp) shortest isoform, Dp40, is a neuron-type Dp. • Dp40 expression is temporally and differentially regulated in comparison to Dp71. • Somatodendritic and nuclear localization of Dp40. • Dp40 is localized to excitatory postsynapses. • Dp40 might play roles in dendritic and synaptic functions. - Abstract: The Duchenne muscular dystrophy (DMD) gene produces multiple dystrophin (Dp) products due to the presence of several promoters. We previously reported the existence of a novel short isoform of Dp, Dp40, in adult mouse brain. However, the exact biochemical expression profile and cytological distribution of the Dp40 protein remain unknown. In this study, we generated a polyclonal antibody against the NH{sub 2}-terminal region of the Dp40 and identified the expression profile of Dp40 in the mouse brain. Through an analysis using embryonic and postnatal mouse cerebrums, we found that Dp40 emerged from the early neonatal stages until adulthood, whereas Dp71, an another Dp short isoform, was highly detected in both prenatal and postnatal cerebrums. Intriguingly, relative expressions of Dp40 and Dp71 were prominent in cultured dissociated neurons and non-neuronal cells derived from mouse hippocampus, respectively. Furthermore, the immunocytological distribution of Dp40 was analyzed in dissociated cultured neurons, revealing that Dp40 is detected in the soma and its dendrites, but not in the axon. It is worthy to note that Dp40 is localized along the subplasmalemmal region of the dendritic shafts, as well as at excitatory postsynaptic sites. Thus, Dp40 was identified as a neuron-type Dp possibly involving dendritic and synaptic functions.

Somatodendritic and excitatory postsynaptic distribution of neuron-type dystrophin isoform, Dp40, in hippocampal neurons

International Nuclear Information System (INIS)

Fujimoto, Takahiro; Itoh, Kyoko; Yaoi, Takeshi; Fushiki, Shinji

2014-01-01

Highlights: • Identification of dystrophin (Dp) shortest isoform, Dp40, is a neuron-type Dp. • Dp40 expression is temporally and differentially regulated in comparison to Dp71. • Somatodendritic and nuclear localization of Dp40. • Dp40 is localized to excitatory postsynapses. • Dp40 might play roles in dendritic and synaptic functions. - Abstract: The Duchenne muscular dystrophy (DMD) gene produces multiple dystrophin (Dp) products due to the presence of several promoters. We previously reported the existence of a novel short isoform of Dp, Dp40, in adult mouse brain. However, the exact biochemical expression profile and cytological distribution of the Dp40 protein remain unknown. In this study, we generated a polyclonal antibody against the NH 2 -terminal region of the Dp40 and identified the expression profile of Dp40 in the mouse brain. Through an analysis using embryonic and postnatal mouse cerebrums, we found that Dp40 emerged from the early neonatal stages until adulthood, whereas Dp71, an another Dp short isoform, was highly detected in both prenatal and postnatal cerebrums. Intriguingly, relative expressions of Dp40 and Dp71 were prominent in cultured dissociated neurons and non-neuronal cells derived from mouse hippocampus, respectively. Furthermore, the immunocytological distribution of Dp40 was analyzed in dissociated cultured neurons, revealing that Dp40 is detected in the soma and its dendrites, but not in the axon. It is worthy to note that Dp40 is localized along the subplasmalemmal region of the dendritic shafts, as well as at excitatory postsynaptic sites. Thus, Dp40 was identified as a neuron-type Dp possibly involving dendritic and synaptic functions

A translational approach for limb vascular delivery of the micro-dystrophin gene without high volume or high pressure for treatment of Duchenne muscular dystrophy

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Chicoine Louis G

2007-09-01

Full Text Available Abstract Background Duchenne muscular dystrophy (DMD is an X-linked recessive disorder with monogenic mutations setting the stage for successful gene therapy treatment. We have completed a study that directly deals with the following key issues that can be directly adapted to a gene therapy clinical trial using rAAV considering the following criteria: 1 A regional vascular delivery approach that will protect the patient from widespread dissemination of virus; 2 an approach to potentially facilitate safe passage of the virus for efficient skeletal muscle transduction; 3 the use of viral doses to accommodate current limitations imposed by vector production methods; 4 and at the same time, achieve a clinically meaningful outcome by transducing multiple muscles in the lower limb to prolong ambulation. Methods The capacity of AAV1, AAV6 or AAV8 to cross the vascular endothelial barrier carrying a micro-dystrophin cDNA was compared under identical conditions with delivery through a catheter placed in the femoral artery of the mdx mouse. Transduction efficiency was assessed by immuno-staining using an antibody (Manex1a that recognizes the N-terminus of micro-dystrophin. The degree of physiologic correction was assessed by measuring tetanic force and protection from eccentric contraction in the extensor digitorum longus muscle (EDL. The vascular delivery paradigm found successful in the mouse was carried to the non-human primate to test its potential translation to boys with DMD. Results Regional vascular delivery resulted in transduction by rAAV8.micro-dystrophin reaching 94.5 ± 0.9 (1 month, 91.3 ± 3.1 (2 months, and 89.6 ± 1.6% (3 months. rAAV6.micro-dystrophin treated animals demonstrated 87.7 ± 6.8 (1 month, 78.9 ± 7.4 (2 months, and 81.2 ± 6.2% (3 months transduction. In striking contrast, rAAV1 demonstrated very low transduction efficiency [0.9 ± 0.3 (1 month, 2.1 ± 0.8 (2 months, and 2.1 ± 0.7% (3 months] by vascular delivery. Micro-dystrophin

Generation of induced pluripotent stem cells from a Becker muscular dystrophy patient carrying a deletion of exons 45-55 of the dystrophin gene (CCMi002BMD-A-9 ∆45-55

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Aoife Gowran

2018-04-01

Full Text Available Becker muscular dystrophy (BMD is a dystrophinopathy caused by mutations in the dystrophin gene on chromosome Xp21. BMD mutations result in truncated semi-functional dystrophin isoforms. Consequently, less severe clinical symptoms become apparent later in life compared to Duchenne muscular dystrophy. Dermal fibroblasts from a BMD patient were electroporated with episomal plasmids containing reprogramming factors to create the induced pluripotent stem cell line: CCMi002BMD-A-9 that showed pluripotent markers, were karyotypically normal and capable of trilineage differentiation. MLPA analyses performed on DNA extracted from CCMi002BMD-A-9 showed an in-frame deletion of exons 45 to 55 (CCMi002BMD-A-9 Δ45-55.

More deletions in the 5{prime} region than in the central region of the dystrophin gene were identified among Filipino Duchenne and Becker muscular dystrophy patients

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NONE

1995-11-06

This report describes mutations in the dystrophin gene and the frequency of these mutations in Filipino pedigrees with Duchenne and Becker muscular dystrophy (DMD/BMD). The findings suggest the presence of genetic variability among DMD/BMD patients in different populations. 13 refs., 1 tab.

Generation of induced pluripotent stem cells from a Becker muscular dystrophy patient carrying a deletion of exons 45-55 of the dystrophin gene (CCMi002BMD-A-9 ∆45-55).

Science.gov (United States)

Gowran, Aoife; Spaltro, Gabriella; Casalnuovo, Federica; Vigorelli, Vera; Spinelli, Pietro; Castiglioni, Elisa; Rovina, Davide; Paganini, Stefania; Di Segni, Marina; Gervasini, Cristina; Nigro, Patrizia; Pompilio, Giulio

2018-04-01

Becker muscular dystrophy (BMD) is a dystrophinopathy caused by mutations in the dystrophin gene on chromosome Xp21. BMD mutations result in truncated semi-functional dystrophin isoforms. Consequently, less severe clinical symptoms become apparent later in life compared to Duchenne muscular dystrophy. Dermal fibroblasts from a BMD patient were electroporated with episomal plasmids containing reprogramming factors to create the induced pluripotent stem cell line: CCMi002BMD-A-9 that showed pluripotent markers, were karyotypically normal and capable of trilineage differentiation. MLPA analyses performed on DNA extracted from CCMi002BMD-A-9 showed an in-frame deletion of exons 45 to 55 (CCMi002BMD-A-9 Δ45-55). Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

A comparative study of N-glycolylneuraminic acid (Neu5Gc and cytotoxic T cell (CT carbohydrate expression in normal and dystrophin-deficient dog and human skeletal muscle.

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Paul T Martin

Full Text Available The expression of N-glycolylneuraminic acid (Neu5Gc and the cytotoxic T cell (CT carbohydrate can impact the severity of muscular dystrophy arising from the loss of dystrophin in mdx mice. Here, we describe the expression of these two glycans in skeletal muscles of dogs and humans with or without dystrophin-deficiency. Neu5Gc expression was highly reduced (>95% in muscle from normal golden retriever crosses (GR, n = 3 and from golden retriever with muscular dystrophy (GRMD, n = 5 dogs at multiple ages (3, 6 and 13 months when compared to mouse muscle, however, overall sialic acid expression in GR and GRMD muscles remained high at all ages. Neu5Gc was expressed on only a minority of GRMD satellite cells, CD8⁺ T lymphocytes and macrophages. Human muscle from normal (no evident disease, n = 3, Becker (BMD, n = 3 and Duchenne (DMD, n = 3 muscular dystrophy individuals had absent to very low Neu5Gc staining, but some punctate intracellular muscle staining was present in BMD and DMD muscles. The CT carbohydrate was localized to the neuromuscular junction in GR muscle, while GRMD muscles had increased expression on a subset of myofibers and macrophages. In humans, the CT carbohydrate was ectopically expressed on the sarcolemmal membrane of some BMD muscles, but not normal human or DMD muscles. These data are consistent with the notion that altered Neu5Gc and CT carbohydrate expression may modify disease severity resulting from dystrophin deficiency in dogs and humans.

Astrogliosis and impaired aquaporin-4 and dystrophin systems in idiopathic normal pressure hydrocephalus.

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Eide, P K; Hansson, H-A

2017-06-19

Idiopathic normal pressure hydrocephalus (iNPH) is one subtype of dementia that may improve following drainage of cerebrospinal fluid (CSF). This prospective observational study explored whether expression of the water channel aquaporin-4 (AQP4) and the anchoring molecule dystrophin 71 (Dp71) are altered at astrocytic perivascular endfeet and in adjacent neuropil of iNPH patient. Observations were related to measurements of pulsatile and static intracranial pressure (ICP). The study included iNPH patients undergoing overnight monitoring of the pulsatile/static ICP in whom a biopsy was taken from the frontal cerebral cortex during placement of the ICP sensor. Reference (Ref) biopsies were sampled from 13 patients who underwent brain surgery for epilepsy, tumours or cerebral aneurysms. The brain tissue specimens were examined by light microscopy, immunohistochemistry, densitometry and morphometry. iNPH patients responding to surgery (n = 44) had elevated pulsatile ICP, indicative of impaired intracranial compliance. As compared to the Ref patients, the cortical biopsies of iNPH patients revealed prominent astrogliosis and reduced expression of AQP4 and Dp71 immunoreactivities in the astrocytic perivascular endfeet and in parts of the adjacent neuropil. There was a significant correlation between degree of astrogliosis and reduction of AQP4 and Dp71 at astrocytic perivascular endfeet. Idiopathic normal pressure hydrocephalus patients responding to CSF diversion present with abnormal pulsatile ICP, indicative of impaired intracranial compliance. A main histopathological finding was astrogliosis and reduction of AQP4 and of Dp71 in astrocytic perivascular endfeet. We propose that the altered AQP4 and Dp71 complex contributes to the subischaemia prevalent in the brain tissue of iNPH. © 2017 British Neuropathological Society.

Formulation of polylactide-co-glycolic acid nanospheres for encapsulation and sustained release of poly(ethylene imine-poly(ethylene glycol copolymers complexed to oligonucleotides

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Wheatley Margaret A

2009-04-01

Full Text Available Abstract Antisense oligonucleotides (AOs have been shown to induce dystrophin expression in muscles cells of patients with Duchenne Muscular Dystrophy (DMD and in the mdx mouse, the murine model of DMD. However, ineffective delivery of AOs limits their therapeutic potential. Copolymers of cationic poly(ethylene imine (PEI and non-ionic poly(ethylene glycol (PEG form stable nanoparticles when complexed with AOs, but the positive surface charge on the resultant PEG-PEI-AO nanoparticles limits their biodistribution. We adapted a modified double emulsion procedure for encapsulating PEG-PEI-AO polyplexes into degradable polylactide-co-glycolic acid (PLGA nanospheres. Formulation parameters were varied including PLGA molecular weight, ester end-capping, and sonication energy/volume. Our results showed successful encapsulation of PEG-PEI-AO within PLGA nanospheres with average diameters ranging from 215 to 240 nm. Encapsulation efficiency ranged from 60 to 100%, and zeta potential measurements confirmed shielding of the PEG-PEI-AO cationic charge. Kinetic measurements of 17 kDa PLGA showed a rapid burst release of about 20% of the PEG-PEI-AO, followed by sustained release of up to 65% over three weeks. To evaluate functionality, PEG-PEI-AO polyplexes were loaded into PLGA nanospheres using an AO that is known to induce dystrophin expression in dystrophic mdx mice. Intramuscular injections of this compound into mdx mice resulted in over 300 dystrophin-positive muscle fibers distributed throughout the muscle cross-sections, approximately 3.4 times greater than for injections of AO alone. We conclude that PLGA nanospheres are effective compounds for the sustained release of PEG-PEI-AO polyplexes in skeletal muscle and concomitant expression of dystrophin, and may have translational potential in treating DMD.

The potential of sarcospan in adhesion complex replacement therapeutics for the treatment of muscular dystrophy

Science.gov (United States)

Marshall, Jamie L.; Kwok, Yukwah; McMorran, Brian; Baum, Linda G.; Crosbie-Watson, Rachelle H.

2013-01-01

Three adhesion complexes span the sarcolemma and facilitate critical connections between the extracellular matrix and the actin cytoskeleton: the dystrophin- and utrophin-glycoprotein complexes and α7β1 integrin. Loss of individual protein components results in a loss of the entire protein complex and muscular dystrophy. Muscular dystrophy is a progressive, lethal wasting disease characterized by repetitive cycles of myofiber degeneration and regeneration. Protein replacement therapy offers a promising approach for the treatment of muscular dystrophy. Recently, we demonstrated that sarcospan facilitates protein-protein interactions amongst the adhesion complexes and is an important therapeutic target. Here, we review current protein replacement strategies, discuss the potential benefits of sarcospan expression, and identify important experiments that must be addressed for sarcospan to move to the clinic. PMID:23601082

Control of complex systems

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Albertos, Pedro; Blanke, Mogens; Isidori, Alberto; Schaufelberger, Walter; Sanz, Ricardo

2001-01-01

The world of artificial systems is reaching complexity levels that es­ cape human understanding. Surface traffic, electricity distribution, air­ planes, mobile communications, etc. , are examples that demonstrate that we are running into problems that are beyond classical scientific or engi­ neering knowledge. There is an ongoing world-wide effort to understand these systems and develop models that can capture its behavior. The reason for this work is clear, if our lack of understanding deepens, we will lose our capability to control these systems and make they behave as we want. Researchers from many different fields are trying to understand and develop theories for complex man-made systems. This book presents re­ search from the perspective of control and systems theory. The book has grown out of activities in the research program Control of Complex Systems (COSY). The program has been sponsored by the Eu­ ropean Science Foundation (ESF) which for 25 years has been one of the leading players in stimula...

Decentralized control of complex systems

CERN Document Server

Siljak, Dragoslav D

2011-01-01

Complex systems require fast control action in response to local input, and perturbations dictate the use of decentralized information and control structures. This much-cited reference book explores the approaches to synthesizing control laws under decentralized information structure constraints.Starting with a graph-theoretic framework for structural modeling of complex systems, the text presents results related to robust stabilization via decentralized state feedback. Subsequent chapters explore optimization, output feedback, the manipulative power of graphs, overlapping decompositions and t

Sparing of the dystrophin-deficient cranial sartorius muscle is associated with classical and novel hypertrophy pathways in GRMD dogs.

Science.gov (United States)

Nghiem, Peter P; Hoffman, Eric P; Mittal, Priya; Brown, Kristy J; Schatzberg, Scott J; Ghimbovschi, Svetlana; Wang, Zuyi; Kornegay, Joe N

2013-11-01

Both Duchenne and golden retriever muscular dystrophy (GRMD) are caused by dystrophin deficiency. The Duchenne muscular dystrophy sartorius muscle and orthologous GRMD cranial sartorius (CS) are relatively spared/hypertrophied. We completed hierarchical clustering studies to define molecular mechanisms contributing to this differential involvement and their role in the GRMD phenotype. GRMD dogs with larger CS muscles had more severe deficits, suggesting that selective hypertrophy could be detrimental. Serial biopsies from the hypertrophied CS and other atrophied muscles were studied in a subset of these dogs. Myostatin showed an age-dependent decrease and an inverse correlation with the degree of GRMD CS hypertrophy. Regulators of myostatin at the protein (AKT1) and miRNA (miR-539 and miR-208b targeting myostatin mRNA) levels were altered in GRMD CS, consistent with down-regulation of myostatin signaling, CS hypertrophy, and functional rescue of this muscle. mRNA and proteomic profiling was used to identify additional candidate genes associated with CS hypertrophy. The top-ranked network included α-dystroglycan and like-acetylglucosaminyltransferase. Proteomics demonstrated increases in myotrophin and spectrin that could promote hypertrophy and cytoskeletal stability, respectively. Our results suggest that multiple pathways, including decreased myostatin and up-regulated miRNAs, α-dystroglycan/like-acetylglucosaminyltransferase, spectrin, and myotrophin, contribute to hypertrophy and functional sparing of the CS. These data also underscore the muscle-specific responses to dystrophin deficiency and the potential deleterious effects of differential muscle involvement. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

The potential of sarcospan in adhesion complex replacement therapeutics for the treatment of muscular dystrophy.

Science.gov (United States)

Marshall, Jamie L; Kwok, Yukwah; McMorran, Brian J; Baum, Linda G; Crosbie-Watson, Rachelle H

2013-09-01

Three adhesion complexes span the sarcolemma and facilitate critical connections between the extracellular matrix and the actin cytoskeleton: the dystrophin- and utrophin-glycoprotein complexes and α7β1 integrin. Loss of individual protein components results in a loss of the entire protein complex and muscular dystrophy. Muscular dystrophy is a progressive, lethal wasting disease characterized by repetitive cycles of myofiber degeneration and regeneration. Protein-replacement therapy offers a promising approach for the treatment of muscular dystrophy. Recently, we demonstrated that sarcospan facilitates protein-protein interactions amongst the adhesion complexes and is an important potential therapeutic target. Here, we review current protein-replacement strategies, discuss the potential benefits of sarcospan expression, and identify important experiments that must be addressed for sarcospan to move to the clinic. © 2013 FEBS.

Analysis and control of complex dynamical systems robust bifurcation, dynamic attractors, and network complexity

CERN Document Server

Imura, Jun-ichi; Ueta, Tetsushi

2015-01-01

This book is the first to report on theoretical breakthroughs on control of complex dynamical systems developed by collaborative researchers in the two fields of dynamical systems theory and control theory. As well, its basic point of view is of three kinds of complexity: bifurcation phenomena subject to model uncertainty, complex behavior including periodic/quasi-periodic orbits as well as chaotic orbits, and network complexity emerging from dynamical interactions between subsystems. Analysis and Control of Complex Dynamical Systems offers a valuable resource for mathematicians, physicists, and biophysicists, as well as for researchers in nonlinear science and control engineering, allowing them to develop a better fundamental understanding of the analysis and control synthesis of such complex systems.

Evaluation of multiplex ligation-dependent probe amplification analysis versus multiplex polymerase chain reaction assays in the detection of dystrophin gene rearrangements in an Iranian population subset

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Nayereh Nouri

2014-01-01

Full Text Available Background: The Duchenne muscular dystrophy (DMD gene is located in the short arm of the X chromosome (Xp21. It spans 2.4 Mb of the human genomic DNA and is composed of 79 exons. Mutations in the Dystrophin gene result in DMD and Becker muscular dystrophy. In this study, the efficiency of multiplex ligation-dependent probe amplification (MLPA over multiplex polymerase chain reaction (PCR assays in an Iranian population was investigated. Materials and Methods: Multiplex PCR assays and MLPA analysis were carried out in 74 patients affected with DMD. Results: Multiplex PCR detected deletions in 51% of the patients with DMD. MLPA analysis could determine all the deletions detected by the multiplex PCR. Additionally, MLPA was able to identify one more deletion and duplication in patients without detectable mutations by multiplex PCR. Moreover, MLPA precisely determined the exact size of the deletions. Conclusion: Although MLPA analysis is more sensitive for detection of deletions and duplications in the dystrophin gene, multiplex PCR might be used for the initial analysis of the boys affected with DMD in the Iranian population as it was able to detect 95% of the rearrangements in patients with DMD.

Dystrophin Hot-Spot Mutants Leading to Becker Muscular Dystrophy Insert More Deeply into Membrane Models than the Native Protein.

Science.gov (United States)

Ameziane-Le Hir, Sarah; Paboeuf, Gilles; Tascon, Christophe; Hubert, Jean-François; Le Rumeur, Elisabeth; Vié, Véronique; Raguénès-Nicol, Céline

2016-07-26

Dystrophin (DYS) is a membrane skeleton protein whose mutations lead to lethal Duchenne muscular dystrophy or to the milder Becker muscular dystrophy (BMD). One third of BMD "in-frame" exon deletions are located in the region that codes for spectrin-like repeats R16 to R21. We focused on four prevalent mutated proteins deleted in this area (called RΔ45-47, RΔ45-48, RΔ45-49, and RΔ45-51 according to the deleted exon numbers), analyzing protein/membrane interactions. Two of the mutants, RΔ45-48 and RΔ45-51, led to mild pathologies and displayed a similar triple coiled-coil structure as the full-length DYS R16-21, whereas the two others, RΔ45-47 and RΔ45-49, induced more severe pathologies and showed "fractional" structures unrelated to the normal one. To explore lipid packing, small unilamellar liposomes (SUVs) and planar monolayers were used at various initial surface pressures. The dissociation constants determined by microscale thermophoresis (MST) were much higher for the full-length DYS R161-21 than for the mutants; thus the wild type protein has weaker SUV binding. Comparing surface pressures after protein adsorption and analysis of atomic force microscopy images of mixed protein/lipid monolayers revealed that the mutants insert more into the lipid monolayer than the wild type does. In fact, in both models every deletion mutant showed more interactions with membranes than the full-length protein did. This means that mutations in the R16-21 part of dystrophin disturb the protein's molecular behavior as it relates to membranes, regardless of whether the accompanying pathology is mild or severe.

Isolation and characterization of neural stem cells from dystrophic mdx mouse

International Nuclear Information System (INIS)

Annese, Tiziana; Corsi, Patrizia; Ruggieri, Simona; Tamma, Roberto; Marinaccio, Christian; Picocci, Sabrina; Errede, Mariella; Specchia, Giorgina; De Luca, Annamaria; Frassanito, Maria Antonia; Desantis, Vanessa; Vacca, Angelo; Ribatti, Domenico; Nico, Beatrice

2016-01-01

The blood-brain barrier (BBB) is altered in mdx mouse, an animal model to study Duchenne muscular dystrophy (DMD). Our previous work demonstrated that perivascular glial endfeet control the selective exchanges between blood and neuropil as well as the BBB development and integrity; the alterations of dystrophin and dystrophin-associated protein complex (DAPs) in the glial cells of mdx mouse, parallel damages of the BBB and increase in vascular permeability. The aim of this study was to improve our knowledge about brain cellular components in the mdx mouse through the isolation, for the first time, of the adult neural stem cells (ANSCs). We characterized them by FACS, electron microscopy, confocal immunofluorescence microscopy, Real Time-PCR and western blotting, and we studied the expression of the DAPs aquaporin-4 (AQP4), potassium channel Kir4.1, α- and β-dystroglycan (αDG, βDG), α-syntrophin (αSyn), and short dystrophin isoform Dp71 proteins. The results showed that the mdx ANSCs expressed CD133 and Nestin receptor as the control ones, but showed a reduction in Notch receptor and altered cell proliferation with an increment in the apoptotic nuclei. Ultrastructurally, they appeared 50% size reduced compared to control ones, with a few cytoplasmic organelles. Moreover, the mdx ANSCs are devoid in full length dystrophin 427, and they expressed post-transcriptional reduction in the Dp71 in parallel with the ubiquitin proteasome activation, and decrement of DAPs proteins which appeared diffused in the cytoplasm and not polarized on the stem cells plasmamembrane, as prevalently observed in the controls. Overall, these results indicate that structural and molecular alterations affect the neural stem cells in the dystrophic brain, whose increased apoptosis and reduced Dp71 and DAPs proteins expression, together with loss in Dp427 dystrophin, could be responsible of the altered mdx glial maintenance and differentiation and consequent failure in the vessels barrier

Isolation and characterization of neural stem cells from dystrophic mdx mouse

Energy Technology Data Exchange (ETDEWEB)

Annese, Tiziana [Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Section of Human Anatomy and Histology, University of Bari Medical School, Bari (Italy); Corsi, Patrizia [Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Section of Physiology, University of Bari Medical School, Bari (Italy); Ruggieri, Simona; Tamma, Roberto; Marinaccio, Christian [Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Section of Human Anatomy and Histology, University of Bari Medical School, Bari (Italy); Picocci, Sabrina [Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Section of Physiology, University of Bari Medical School, Bari (Italy); Errede, Mariella [Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Section of Human Anatomy and Histology, University of Bari Medical School, Bari (Italy); Specchia, Giorgina [Department of Emergency and Transplantation, Section of Hematology, University of Bari Medical School, Bari (Italy); De Luca, Annamaria [Department of Bioscience, Biotechnology and Pharmacological Sciences, Section of Pharmacology, University of Bari (Italy); Frassanito, Maria Antonia; Desantis, Vanessa; Vacca, Angelo [Department of Internal Medicine and Oncology, University of Bari Medical School, Bari (Italy); Ribatti, Domenico, E-mail: domenico.ribatti@uniba.it [Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Section of Human Anatomy and Histology, University of Bari Medical School, Bari (Italy); National Cancer Institute “Giovanni Paolo II”, Bari (Italy); Nico, Beatrice, E-mail: beatrice.nico@uniba.it [Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Section of Human Anatomy and Histology, University of Bari Medical School, Bari (Italy)

2016-05-01

The blood-brain barrier (BBB) is altered in mdx mouse, an animal model to study Duchenne muscular dystrophy (DMD). Our previous work demonstrated that perivascular glial endfeet control the selective exchanges between blood and neuropil as well as the BBB development and integrity; the alterations of dystrophin and dystrophin-associated protein complex (DAPs) in the glial cells of mdx mouse, parallel damages of the BBB and increase in vascular permeability. The aim of this study was to improve our knowledge about brain cellular components in the mdx mouse through the isolation, for the first time, of the adult neural stem cells (ANSCs). We characterized them by FACS, electron microscopy, confocal immunofluorescence microscopy, Real Time-PCR and western blotting, and we studied the expression of the DAPs aquaporin-4 (AQP4), potassium channel Kir4.1, α- and β-dystroglycan (αDG, βDG), α-syntrophin (αSyn), and short dystrophin isoform Dp71 proteins. The results showed that the mdx ANSCs expressed CD133 and Nestin receptor as the control ones, but showed a reduction in Notch receptor and altered cell proliferation with an increment in the apoptotic nuclei. Ultrastructurally, they appeared 50% size reduced compared to control ones, with a few cytoplasmic organelles. Moreover, the mdx ANSCs are devoid in full length dystrophin 427, and they expressed post-transcriptional reduction in the Dp71 in parallel with the ubiquitin proteasome activation, and decrement of DAPs proteins which appeared diffused in the cytoplasm and not polarized on the stem cells plasmamembrane, as prevalently observed in the controls. Overall, these results indicate that structural and molecular alterations affect the neural stem cells in the dystrophic brain, whose increased apoptosis and reduced Dp71 and DAPs proteins expression, together with loss in Dp427 dystrophin, could be responsible of the altered mdx glial maintenance and differentiation and consequent failure in the vessels barrier

Deletion of exon 26 of the dystrophin gene is associated with a mild Becker muscular dystrophy phenotype

DEFF Research Database (Denmark)

Witting, Nanna; Duno, Morten; Vissing, John

2011-01-01

With the possible introduction of exon skipping therapy in Duchenne muscular dystrophy, it has become increasingly important to know the role of each exon of the dystrophin gene to protein expression, and thus the phenotype. In this report, we present two related men with an unusually mild BMD...... skipping therapy for Duchenne muscular dystrophy. This report also shows that BMD may present with a normal CK....... associated with an exon 26 deletion. The proband, a 23-year-old man, had slightly delayed motor milestones, walking 1 1/2 years old. He had no complaints of muscle weakness, but had muscle pain. Clinical examination revealed no muscle wasting or loss of power, but his CK was 1500-7000 U/l. Muscle biopsy...

Immunohistochemical alterations of dystrophin in congenital muscular dystrophy Alterações imuno-hístoquímicas da distrofina na distrofia muscular congênita

Directory of Open Access Journals (Sweden)

Lineu Cesar Werneck

1995-09-01

Full Text Available The dystrophin distribution in the plasma muscle membrane using immunohystochemistry was studied in 22 children with congenital muscular dystrophy. The dystrophin was detected by immunofluorescence in muscle biopsy through a polyclonal antibody. All the cases had patchy interruptions of the fluorescence in the plasma membrane. A large patchy interruption of the sarcolemma was found in 17 cases, small interruption in 12, and a combination of large and small patchy discontinuity in 7. Small gaps around the fiber like a rosary were found in 15 cases. The frequency of these abnormalities ranged cases from: all fibers in 5 cases, frequent in 8, occasional in 5, and rare in 4. Five cases had total absence of immunofluorescence. These results suggest that the dystrophin expression is abnormal in this group of children and that this type of abnormalities can not be differentiated from early Becker muscular dystrophy nor childhood autosomal recessive muscular dystrophy through immunohystochemistry alone.Foi estudada a distribuição da distrofina na membrana plasmática das fibras musculares em 22 crianças com distrofia muscular congênita, através de técnicas de imuno-histoquímica. A distrofina foi identificada nas biópsias musculares processadas a fresco, por técnicas de imunofluorescência utilizando anticorpos policlonais. Todos os casos tinham interrupções da imunofluorescência na membrana plasmática. Em 17 elas eram grandes, em 12 eram pequenas e em 7 eram de ambos os tipos. Fibras com interrupções pequenas e constantes, como um rosário, foram vistas em 15 casos. Essas anormalidades estavam presentes em todas as fibras em 5 casos, eram frequentes em 8, ocasionais em 5 e raras em 4. Cinco casos mostraram fibras sem distrofina. Esses dados sugerem que a expressão da distrofina é anormal nesse grupo de crianças. Essas anormalidades podem também ser encontradas em casos precoces de distrofia muscular de Becker e distrofia autoss

Neuronal nitric oxide synthase-rescue of dystrophin/utrophin double knockout mice does not require nNOS localization to the cell membrane.

Directory of Open Access Journals (Sweden)

Michelle Wehling-Henricks

Full Text Available Survival of dystrophin/utrophin double-knockout (dko mice was increased by muscle-specific expression of a neuronal nitric oxide synthase (nNOS transgene. Dko mice expressing the transgene (nNOS TG+/dko experienced delayed onset of mortality and increased life-span. The nNOS TG+/dko mice demonstrated a significant decrease in the concentration of CD163+, M2c macrophages that can express arginase and promote fibrosis. The decrease in M2c macrophages was associated with a significant reduction in fibrosis of heart, diaphragm and hindlimb muscles of nNOS TG+/dko mice. The nNOS transgene had no effect on the concentration of cytolytic, CD68+, M1 macrophages. Accordingly, we did not observe any change in the extent of muscle fiber lysis in the nNOS TG+/dko mice. These findings show that nNOS/NO (nitric oxide-mediated decreases in M2c macrophages lead to a reduction in the muscle fibrosis that is associated with increased mortality in mice lacking dystrophin and utrophin. Interestingly, the dramatic and beneficial effects of the nNOS transgene were not attributable to localization of nNOS protein at the cell membrane. We did not detect any nNOS protein at the sarcolemma in nNOS TG+/dko muscles. This important observation shows that sarcolemmal localization is not necessary for nNOS to have beneficial effects in dystrophic tissue and the presence of nNOS in the cytosol of dystrophic muscle fibers can ameliorate the pathology and most importantly, significantly increase life-span.

Profound human/mouse differences in alpha-dystrobrevin isoforms: a novel syntrophin-binding site and promoter missing in mouse and rat

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Jin Hong

2009-12-01

Full Text Available Abstract Background The dystrophin glycoprotein complex is disrupted in Duchenne muscular dystrophy and many other neuromuscular diseases. The principal heterodimeric partner of dystrophin at the heart of the dystrophin glycoprotein complex in the main clinically affected tissues (skeletal muscle, heart and brain is its distant relative, α-dystrobrevin. The α-dystrobrevin gene is subject to complex transcriptional and post-transcriptional regulation, generating a substantial range of isoforms by alternative promoter use, alternative polyadenylation and alternative splicing. The choice of isoform is understood, amongst other things, to determine the stoichiometry of syntrophins (and their ligands in the dystrophin glycoprotein complex. Results We show here that, contrary to the literature, most α-dystrobrevin genes, including that of humans, encode three distinct syntrophin-binding sites, rather than two, resulting in a greatly enhanced isoform repertoire. We compare in detail the quantitative tissue-specific expression pattern of human and mouse α-dystrobrevin isoforms, and show that two major gene features (the novel syntrophin-binding site-encoding exon and the internal promoter and first exon of brain-specific isoforms α-dystrobrevin-4 and -5 are present in most mammals but specifically ablated in mouse and rat. Conclusion Lineage-specific mutations in the murids mean that the mouse brain has fewer than half of the α-dystrobrevin isoforms found in the human brain. Our finding that there are likely to be fundamental functional differences between the α-dystrobrevins (and therefore the dystrophin glycoprotein complexes of mice and humans raises questions about the current use of the mouse as the principal model animal for studying Duchenne muscular dystrophy and other related disorders, especially the neurological aspects thereof.

Evaluation of skeletal and cardiac muscle function after chronic administration of thymosin beta-4 in the dystrophin deficient mouse.

Directory of Open Access Journals (Sweden)

Christopher F Spurney

2010-01-01

Full Text Available Thymosin beta-4 (Tbeta4 is a ubiquitous protein with many properties relating to cell proliferation and differentiation that promotes wound healing and modulates inflammatory mediators. We studied the effects of chronic administration of Tbeta4 on the skeletal and cardiac muscle of dystrophin deficient mdx mice, the mouse model of Duchenne muscular dystrophy. Female wild type (C57BL10/ScSnJ and mdx mice, 8-10 weeks old, were treated with 150 microg of Tbeta4 twice a week for 6 months. To promote muscle pathology, mice were exercised for 30 minutes twice a week. Skeletal and cardiac muscle function were assessed via grip strength and high frequency echocardiography. Localization of Tbeta4 and amount of fibrosis were quantified using immunohistochemistry and Gomori's tri-chrome staining, respectively. Mdx mice treated with Tbeta4 showed a significant increase in skeletal muscle regenerating fibers compared to untreated mdx mice. Tbeta4 stained exclusively in the regenerating fibers of mdx mice. Although untreated mdx mice had significantly decreased skeletal muscle strength compared to untreated wild type, there were no significant improvements in mdx mice after treatment. Systolic cardiac function, measured as percent shortening fraction, was decreased in untreated mdx mice compared to untreated wild type and there was no significant difference after treatment in mdx mice. Skeletal and cardiac muscle fibrosis were also significantly increased in untreated mdx mice compared to wild type, but there was no significant improvement in treated mdx mice. In exercised dystrophin deficient mice, chronic administration of Tbeta4 increased the number of regenerating fibers in skeletal muscle and could have a potential role in treatment of skeletal muscle disease in Duchenne muscular dystrophy.

Alterations in the muscle force transfer apparatus in aged rats during unloading and reloading: Impact of microRNA-31.

Science.gov (United States)

Hughes, David C; Marcotte, George R; Baehr, Leslie M; West, Daniel W D; Marshall, Andrea G; Ebert, Scott M; Davidyan, Arik; Adams, Christopher M; Bodine, Sue C; Baar, Keith

2018-05-03

Force transfer is integral for maintaining skeletal muscle structure and function. One important component is dystrophin. There is limited understanding of how force transfer is impacted by age and loading. Here, we investigate the force transfer apparatus in muscles of adult and old rats exposed to periods of disuse and reloading. Our results demonstrate an increase in dystrophin protein during the reloading phase in the adult TA muscle that is delayed in old. The consequence of this delay is an increased susceptibility towards contraction-induced muscle injury. Central to the lack of dystrophin protein is an increase in miR-31, a microRNA that inhibits dystrophin translation. In vivo electroporation with a miR-31 sponge led to increased dystrophin protein and decreased contraction-induced muscle injury in old skeletal muscle. Overall, our results detail the importance of the force transfer apparatus and provide new mechanisms for contraction-induced injury in aging skeletal muscle. In healthy muscle, the dystrophin-associated glycoprotein (DGC) and integrin/focal adhesion complexes, intermediate filaments, and Z-line proteins transmit force from the contractile proteins to the extracellular matrix. How loading and age affect these proteins is poorly understood. The experiments reported here sought to determine the effect of aging on the force transfer apparatus following muscle unloading and reloading. Adult (9 months) and old (29 months) rats were subjected to 14 days hindlimb unloading (HU) and 1, 3, 7 and 14 days of reloading (REL). The DGC complex, intermediate filament and z-line protein and mRNA levels, as well as dystrophin-targeting miRNAs (miR-31, -146b and -374) were examined in the tibialis anterior (TA) and medial gastrocnemius (MG) muscles at both ages. There was a significant increase in dystrophin protein levels (2.79-fold) upon 3 days of reloading in the adult TA muscle that did not occur in the old rats (p ≤ 0.05), and the rise in

Complex systems and networks dynamics, controls and applications

CERN Document Server

Yu, Xinghuo; Chen, Guanrong; Yu, Wenwu

2016-01-01

This elementary book provides some state-of-the-art research results on broad disciplinary sciences on complex networks. It presents an in-depth study with detailed description of dynamics, controls and applications of complex networks. The contents of this book can be summarized as follows. First, the dynamics of complex networks, for example, the cluster dynamic analysis by using kernel spectral methods, community detection algorithms in bipartite networks, epidemiological modeling with demographics and epidemic spreading on multi-layer networks, are studied. Second, the controls of complex networks are investigated including topics like distributed finite-time cooperative control of multi-agent systems by applying homogenous-degree and Lyapunov methods, composite finite-time containment control for disturbed second-order multi-agent systems, fractional-order observer design of multi-agent systems, chaos control and anticontrol of complex systems via Parrondos game and many more. Third, the applications of ...

Complexity Control of Fast Motion Estimation in H.264/MPEG-4 AVC with Rate-Distortion-Complexity optimization

DEFF Research Database (Denmark)

Wu, Mo; Forchhammer, Søren; Aghito, Shankar Manuel

2007-01-01

A complexity control algorithm for H.264 advanced video coding is proposed. The algorithm can control the complexity of integer inter motion estimation for a given target complexity. The Rate-Distortion-Complexity performance is improved by a complexity prediction model, simple analysis of the pa...... statistics and a control scheme. The algorithm also works well for scene change condition. Test results for coding interlaced video (720x576 PAL) are reported.......A complexity control algorithm for H.264 advanced video coding is proposed. The algorithm can control the complexity of integer inter motion estimation for a given target complexity. The Rate-Distortion-Complexity performance is improved by a complexity prediction model, simple analysis of the past...

Complex systems relationships between control, communications and computing

CERN Document Server

2016-01-01

This book gives a wide-ranging description of the many facets of complex dynamic networks and systems within an infrastructure provided by integrated control and supervision: envisioning, design, experimental exploration, and implementation. The theoretical contributions and the case studies presented can reach control goals beyond those of stabilization and output regulation or even of adaptive control. Reporting on work of the Control of Complex Systems (COSY) research program, Complex Systems follows from and expands upon an earlier collection: Control of Complex Systems by introducing novel theoretical techniques for hard-to-control networks and systems. The major common feature of all the superficially diverse contributions encompassed by this book is that of spotting and exploiting possible areas of mutual reinforcement between control, computing and communications. These help readers to achieve not only robust stable plant system operation but also properties such as collective adaptivity, integrity an...

Stem cells from umbilical cord blood do have myogenic potential, with and without differentiation induction in vitro

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Gollop Thomaz R

2009-01-01

Full Text Available Abstract The dystrophin gene, located at Xp21, codifies dystrophin, which is part of a protein complex responsible for the membrane stability of muscle cells. Its absence on muscle causes Duchenne Muscular Dystrophy (DMD, a severe disorder, while a defect of muscle dystrophin causes Becker Muscular Dystrophy (DMB, a milder disease. The replacement of the defective muscle through stem cells transplantation is a possible future treatment for these patients. Our objective was to analyze the potential of CD34+ stem cells from umbilical cord blood to differentiate in muscle cells and express dystrophin, in vitro. Protein expression was analyzed by Immunofluorescence, Western Blotting (WB and Reverse Transcriptase – Polymerase Chain Reaction (RT-PCR. CD34+ stem cells and myoblasts from a DMD affected patient started to fuse with muscle cells immediately after co-cultures establishment. Differentiation in mature myotubes was observed after 15 days and dystrophin-positive regions were detected through Immunofluorescence analysis. However, WB or RT-PCR analysis did not detect the presence of normal dystrophin in co-cultures of CD34+ and DMD or DMB affected patients' muscle cells. In contrast, some CD34+ stem cells differentiated in dystrophin producers' muscle cells, what was observed by WB, reinforcing that this progenitor cell has the potential to originate muscle dystrophin in vitro, and not just in vivo like reported before.

Pinning impulsive control algorithms for complex network

Energy Technology Data Exchange (ETDEWEB)

Sun, Wen [School of Information and Mathematics, Yangtze University, Jingzhou 434023 (China); Lü, Jinhu [Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China); Chen, Shihua [College of Mathematics and Statistics, Wuhan University, Wuhan 430072 (China); Yu, Xinghuo [School of Electrical and Computer Engineering, RMIT University, Melbourne VIC 3001 (Australia)

2014-03-15

In this paper, we further investigate the synchronization of complex dynamical network via pinning control in which a selection of nodes are controlled at discrete times. Different from most existing work, the pinning control algorithms utilize only the impulsive signals at discrete time instants, which may greatly improve the communication channel efficiency and reduce control cost. Two classes of algorithms are designed, one for strongly connected complex network and another for non-strongly connected complex network. It is suggested that in the strongly connected network with suitable coupling strength, a single controller at any one of the network's nodes can always pin the network to its homogeneous solution. In the non-strongly connected case, the location and minimum number of nodes needed to pin the network are determined by the Frobenius normal form of the coupling matrix. In addition, the coupling matrix is not necessarily symmetric or irreducible. Illustrative examples are then given to validate the proposed pinning impulsive control algorithms.

Pinning impulsive control algorithms for complex network

International Nuclear Information System (INIS)

Sun, Wen; Lü, Jinhu; Chen, Shihua; Yu, Xinghuo

2014-01-01

In this paper, we further investigate the synchronization of complex dynamical network via pinning control in which a selection of nodes are controlled at discrete times. Different from most existing work, the pinning control algorithms utilize only the impulsive signals at discrete time instants, which may greatly improve the communication channel efficiency and reduce control cost. Two classes of algorithms are designed, one for strongly connected complex network and another for non-strongly connected complex network. It is suggested that in the strongly connected network with suitable coupling strength, a single controller at any one of the network's nodes can always pin the network to its homogeneous solution. In the non-strongly connected case, the location and minimum number of nodes needed to pin the network are determined by the Frobenius normal form of the coupling matrix. In addition, the coupling matrix is not necessarily symmetric or irreducible. Illustrative examples are then given to validate the proposed pinning impulsive control algorithms

Enabling Controlling Complex Networks with Local Topological Information.

Science.gov (United States)

Li, Guoqi; Deng, Lei; Xiao, Gaoxi; Tang, Pei; Wen, Changyun; Hu, Wuhua; Pei, Jing; Shi, Luping; Stanley, H Eugene

2018-03-15

Complex networks characterize the nature of internal/external interactions in real-world systems including social, economic, biological, ecological, and technological networks. Two issues keep as obstacles to fulfilling control of large-scale networks: structural controllability which describes the ability to guide a dynamical system from any initial state to any desired final state in finite time, with a suitable choice of inputs; and optimal control, which is a typical control approach to minimize the cost for driving the network to a predefined state with a given number of control inputs. For large complex networks without global information of network topology, both problems remain essentially open. Here we combine graph theory and control theory for tackling the two problems in one go, using only local network topology information. For the structural controllability problem, a distributed local-game matching method is proposed, where every node plays a simple Bayesian game with local information and local interactions with adjacent nodes, ensuring a suboptimal solution at a linear complexity. Starring from any structural controllability solution, a minimizing longest control path method can efficiently reach a good solution for the optimal control in large networks. Our results provide solutions for distributed complex network control and demonstrate a way to link the structural controllability and optimal control together.

Model complexity control for hydrologic prediction

NARCIS (Netherlands)

Schoups, G.; Van de Giesen, N.C.; Savenije, H.H.G.

2008-01-01

A common concern in hydrologic modeling is overparameterization of complex models given limited and noisy data. This leads to problems of parameter nonuniqueness and equifinality, which may negatively affect prediction uncertainties. A systematic way of controlling model complexity is therefore

A Cryo Complex Control

CERN Document Server

Alferov, V; Fedorchenko, V; Ivanova, N; Kholkin, A; Klimov, S; Krendelev, V; Kuznetsov, S; Lukyantsev, A; Lutchev, A; Milutkin, V; Sytin, A N; Vasilev, D

2004-01-01

A Cryogenic complex is being constructed to provide by liquid helium and nitrogen the RF-separator of kaons. About 500 parameters including temperature (1,8…300)K, liquid helium/nitrogen level, vacuum, 300 digital signals have to be measured, 70 commands generated, 20 closed loops activated. The paper describes controls electronics which includes home made I8051 compatible controllers connected by the CAN field bus to a bus controller and interface electronic modules for: - temperature measurements; - liquid Ni and He level measurements; - vacuum pumps current measurements; - analog and digital signals measurements and generations. The modules are tested together with signal imitators within a vertical slice of the Control System based on EPICS tools.

Complex Projective Synchronization in Drive-Response Stochastic Complex Networks by Impulsive Pinning Control

Directory of Open Access Journals (Sweden)

Xuefei Wu

2014-01-01

Full Text Available The complex projective synchronization in drive-response stochastic coupled networks with complex-variable systems is considered. The impulsive pinning control scheme is adopted to achieve complex projective synchronization and several simple and practical sufficient conditions are obtained in a general drive-response network. In addition, the adaptive feedback algorithms are proposed to adjust the control strength. Several numerical simulations are provided to show the effectiveness and feasibility of the proposed methods.

Control of complex physically simulated robot groups

Science.gov (United States)

Brogan, David C.

2001-10-01

Actuated systems such as robots take many forms and sizes but each requires solving the difficult task of utilizing available control inputs to accomplish desired system performance. Coordinated groups of robots provide the opportunity to accomplish more complex tasks, to adapt to changing environmental conditions, and to survive individual failures. Similarly, groups of simulated robots, represented as graphical characters, can test the design of experimental scenarios and provide autonomous interactive counterparts for video games. The complexity of writing control algorithms for these groups currently hinders their use. A combination of biologically inspired heuristics, search strategies, and optimization techniques serve to reduce the complexity of controlling these real and simulated characters and to provide computationally feasible solutions.

Subjective task complexity in the control room

International Nuclear Information System (INIS)

Braarud, Per Oeivind

2000-05-01

Understanding of what makes a control room situation difficult to handle is important when studying operator performance, both with respect to prediction as well as improvement of the human performance. Previous exploratory work on complexity showed a potential for prediction and explanation of operator performance. This report investigates in further detail the theoretical background and the structure of operator rated task complexity. The report complements the previous work on complexity to make a basis for development of operator performance analysis tools. The first part of the report outlines an approach for studying the complexity of the control room crew's work. The approach draws upon man-machine research as well as problem solving research. The approach identifies five complexity-shaping components: 'task work characteristics', 'teamwork characteristics', 'individual skill', 'teamwork skill', and 'interface and support systems'. The crew's work complexity is related to concepts of human performance quality and human error. The second part of the report is a post-hoc exploratory analysis of four empirical HRP studies, where operators' conception of the complexity of control room work is assessed by questionnaires. The analysis deals with the structure of complexity questionnaire ratings, and the relationship between complexity ratings and human performance measures. The main findings from the analysis of structure was the identification of three task work factors which were named Masking, Information load and Temporal demand, and in addition the identification of one interface factor which was named Navigation. Post-hoc analysis suggests that operator's subjective complexity, which was assessed by questionnaires, is related to workload, task and system performance, and operator's self-rated performance. (Author). 28 refs., 47 tabs

Sequence characterisation of deletion breakpoints in the dystrophin gene by PCR

Energy Technology Data Exchange (ETDEWEB)

Abbs, S.; Sandhu, S.; Bobrow, M. [Guy`s Hospital, London (United Kingdom)

1994-09-01

Partial deletions of the dystrophin gene account for 65% of cases of Duchenne muscular dystrophy. A high proportion of these structural changes are generated by new mutational events, and lie predominantly within two `hotspot` regions, yet the underlying reasons for this are not known. We are characterizing and sequencing the regions surrounding deletion breakpoints in order to: (i) investigate the mechanisms of deletion mutation, and (ii) enable the design of PCR assays to specifically amplify mutant and normal sequences, allowing us to search for the presence of somatic mosaicism in appropriate family members. Using this approach we have been able to demonstrate the presence of somatic mosaicism in a maternal grandfather of a DMD-affected male, deleted for exons 49-50. Three deletions, namely of exons 48-49, 49-50, and 50, have been characterized using a PCR approach that avoids any cloning procedures. Breakpoints were initially localized to within regions of a few kilobases using Southern blot restriction analyses with exon-specific probes and PCR amplification of exonic and intronic loci. Sequencing was performed directly on PCR products: (i) mutant sequences were obtained from long-range or inverse-PCR across the deletion junction fragments, and (ii) normal sequences were obtained from the products of standard PCR, vectorette PCR, or inverse-PCR performed on YACs. Further characterization of intronic sequences will allow us to amplify and sequence across other deletion breakpoints and increase our knowledge of the mechanisms of mutation in the dystophin gene.

Adaptive control for a class of nonlinear complex dynamical systems with uncertain complex parameters and perturbations.

Directory of Open Access Journals (Sweden)

Jian Liu

Full Text Available In this paper, adaptive control is extended from real space to complex space, resulting in a new control scheme for a class of n-dimensional time-dependent strict-feedback complex-variable chaotic (hyperchaotic systems (CVCSs in the presence of uncertain complex parameters and perturbations, which has not been previously reported in the literature. In detail, we have developed a unified framework for designing the adaptive complex scalar controller to ensure this type of CVCSs asymptotically stable and for selecting complex update laws to estimate unknown complex parameters. In particular, combining Lyapunov functions dependent on complex-valued vectors and back-stepping technique, sufficient criteria on stabilization of CVCSs are derived in the sense of Wirtinger calculus in complex space. Finally, numerical simulation is presented to validate our theoretical results.

Adaptive control for a class of nonlinear complex dynamical systems with uncertain complex parameters and perturbations.

Science.gov (United States)

Liu, Jian; Liu, Kexin; Liu, Shutang

2017-01-01

In this paper, adaptive control is extended from real space to complex space, resulting in a new control scheme for a class of n-dimensional time-dependent strict-feedback complex-variable chaotic (hyperchaotic) systems (CVCSs) in the presence of uncertain complex parameters and perturbations, which has not been previously reported in the literature. In detail, we have developed a unified framework for designing the adaptive complex scalar controller to ensure this type of CVCSs asymptotically stable and for selecting complex update laws to estimate unknown complex parameters. In particular, combining Lyapunov functions dependent on complex-valued vectors and back-stepping technique, sufficient criteria on stabilization of CVCSs are derived in the sense of Wirtinger calculus in complex space. Finally, numerical simulation is presented to validate our theoretical results.

Low-complexity controllers for time-delay systems

CERN Document Server

Özbay, Hitay; Bonnet, Catherine; Mounier, Hugues

2014-01-01

This volume in the newly established series Advances in Delays and Dynamics (ADD@S) provides a collection of recent results on the design and analysis of Low Complexity Controllers for Time Delay Systems. A widely used indirect method to obtain low order controllers for time delay systems is to design a controller for the reduced order model of the plant. In the dual indirect approach, an infinite dimensional controller is designed first for the original plant model; then, the controller is approximated by keeping track of the degradation in performance and stability robustness measures. The present volume includes new techniques used at different stages of the indirect approach. It also includes new direct design methods for fixed structure and low order controllers. On the other hand, what is meant by low complexity controller is not necessarily low order controller. For example, Smith predictor or similar type of controllers include a copy of the plant internally in the controller, so they are technically ...

Complexity and Control: Towards a Rigorous Behavioral Theory of Complex Dynamical Systems

Science.gov (United States)

Ivancevic, Vladimir G.; Reid, Darryn J.

We introduce our motive for writing this book on complexity and control with a popular "complexity myth," which seems to be quite wide spread among chaos and complexity theory fashionistas: quote>Low-dimensional systems usually exhibit complex behaviours (which we know fromMay's studies of the Logisticmap), while high-dimensional systems usually exhibit simple behaviours (which we know from synchronisation studies of the Kuramoto model)...quote> We admit that this naive view on complex (e.g., human) systems versus simple (e.g., physical) systems might seem compelling to various technocratic managers and politicians; indeed, the idea makes for appealing sound-bites. However, it is enough to see both in the equations and computer simulations of pendula of various degree - (i) a single pendulum, (ii) a double pendulum, and (iii) a triple pendulum - that this popular myth is plain nonsense. The only thing that we can learn from it is what every tyrant already knows: by using force as a strong means of control, it is possible to effectively synchronise even hundreds of millions of people, at least for a while.

Controlling extreme events on complex networks

Science.gov (United States)

Chen, Yu-Zhong; Huang, Zi-Gang; Lai, Ying-Cheng

2014-08-01

Extreme events, a type of collective behavior in complex networked dynamical systems, often can have catastrophic consequences. To develop effective strategies to control extreme events is of fundamental importance and practical interest. Utilizing transportation dynamics on complex networks as a prototypical setting, we find that making the network ``mobile'' can effectively suppress extreme events. A striking, resonance-like phenomenon is uncovered, where an optimal degree of mobility exists for which the probability of extreme events is minimized. We derive an analytic theory to understand the mechanism of control at a detailed and quantitative level, and validate the theory numerically. Implications of our finding to current areas such as cybersecurity are discussed.

Synchronizability on complex networks via pinning control

Indian Academy of Sciences (India)

Keywords. Complex network; the pinning synchronization; synchronizability. ... The findings reveal the relationship between the decreasing speed of maximum eigenvalue sequence of the principal submatrices for coupling matrix and the synchronizability on complex networks via pinning control. We discuss the ...

Black bear parathyroid hormone has greater anabolic effects on trabecular bone in dystrophin-deficient mice than in wild type mice.

Science.gov (United States)

Gray, Sarah K; McGee-Lawrence, Meghan E; Sanders, Jennifer L; Condon, Keith W; Tsai, Chung-Jui; Donahue, Seth W

2012-09-01

Duchenne muscular dystrophy (DMD) is an X-linked neuromuscular disease that has deleterious consequences in muscle and bone, leading to decreased mobility, progressive osteoporosis, and premature death. Patients with DMD experience a higher-than-average fracture rate, particularly in the proximal and distal femur and proximal tibia. The dystrophin-deficient mdx mouse is a model of DMD that demonstrates muscle degeneration and fibrosis and osteoporosis. Parathyroid hormone, an effective anabolic agent for post-menopausal and glucocorticoid-induced osteoporosis, has not been explored for DMD. Black bear parathyroid hormone (bbPTH) has been implicated in the maintenance of bone properties during extended periods of disuse (hibernation). We cloned bbPTH and found 9 amino acid residue differences from human PTH. Apoptosis was mitigated and cAMP was activated by bbPTH in osteoblast cultures. We administered 28nmol/kg of bbPTH 1-84 to 4-week old male mdx and wild type mice via daily (5×/week) subcutaneous injection for 6 weeks. Vehicle-treated mdx mice had 44% lower trabecular bone volume fraction than wild type mice. No changes were found in femoral cortical bone geometry or mechanical properties with bbPTH treatment in wild type mice, and only medio-lateral moment of inertia changed with bbPTH treatment in mdx femurs. However, μCT analyses of the trabecular regions of the distal femur and proximal tibia showed marked increases in bone volume fraction with bbPTH treatment, with a greater anabolic response (7-fold increase) in mdx mice than wild type mice (2-fold increase). Trabecular number increased in mdx long bone, but not wild type bone. Additionally, greater osteoblast area and decreased osteoclast area were observed with bbPTH treatment in mdx mice. The heightened response to PTH in mdx bone compared to wild type suggests a link between dystrophin deficiency, altered calcium signaling, and bone. These findings support further investigation of PTH as an anabolic

Sarcoglycan complex in masseter and sternocleidomastoid muscles of baboons: an immunohistochemical study

Directory of Open Access Journals (Sweden)

G. Cutroneo

2015-06-01

Full Text Available The sarcoglycan complex consists of a group of single-pass transmembrane glycoproteins that are essential to maintain the integrity of muscle membranes. Any mutation in each sarcoglycan gene causes a series of recessive autosomal dystrophin-positive muscular dystrophies. Negative fibres for sarcoglycans have never been found in healthy humans and animals. In this study, we have investigated whether the social ranking has an influence on the expression of sarcoglycans in the skeletal muscles of healthy baboons. Biopsies of masseter and sternocleidomastoid muscles were processed for confocal immunohistochemical detection of sarcoglycans. Our findings showed that baboons from different social rankings exhibited different sarcoglycan expression profiles. While in dominant baboons almost all muscles were stained for sarcoglycans, only 55% of muscle fibres showed a significant staining. This different expression pattern is likely to be due to the living conditions of these primates. Sarcoglycans which play a key role in muscle activity by controlling contractile forces may influence the phenotype of muscle fibres, thus determining an adaptation to functional conditions. We hypothesize that this intraspecies variation reflects an epigenetic modification of the muscular protein network that allows baboons to adapt progressively to a different social status.

Evaluation of point mutations in dystrophin gene in Iranian Duchenne and Becker muscular dystrophy patients: introducing three novel variants.

Science.gov (United States)

Haghshenas, Maryam; Akbari, Mohammad Taghi; Karizi, Shohreh Zare; Deilamani, Faravareh Khordadpoor; Nafissi, Shahriar; Salehi, Zivar

2016-06-01

Duchenne and Becker muscular dystrophies (DMD and BMD) are X-linked neuromuscular diseases characterized by progressive muscular weakness and degeneration of skeletal muscles. Approximately two-thirds of the patients have large deletions or duplications in the dystrophin gene and the remaining one-third have point mutations. This study was performed to evaluate point mutations in Iranian DMD/BMD male patients. A total of 29 DNA samples from patients who did not show any large deletion/duplication mutations following multiplex polymerase chain reaction (PCR) and multiplex ligation-dependent probe amplification (MLPA) screening were sequenced for detection of point mutations in exons 50-79. Also exon 44 was sequenced in one sample in which a false positive deletion was detected by MLPA method. Cycle sequencing revealed four nonsense, one frameshift and two splice site mutations as well as two missense variants.

Controlling Complex Systems and Developing Dynamic Technology

Science.gov (United States)

Avizienis, Audrius Victor

In complex systems, control and understanding become intertwined. Following Ilya Prigogine, we define complex systems as having control parameters which mediate transitions between distinct modes of dynamical behavior. From this perspective, determining the nature of control parameters and demonstrating the associated dynamical phase transitions are practically equivalent and fundamental to engaging with complexity. In the first part of this work, a control parameter is determined for a non-equilibrium electrochemical system by studying a transition in the morphology of structures produced by an electroless deposition reaction. Specifically, changing the size of copper posts used as the substrate for growing metallic silver structures by the reduction of Ag+ from solution under diffusion-limited reaction conditions causes a dynamical phase transition in the crystal growth process. For Cu posts with edge lengths on the order of one micron, local forces promoting anisotropic growth predominate, and the reaction produces interconnected networks of Ag nanowires. As the post size is increased above 10 microns, the local interfacial growth reaction dynamics couple with the macroscopic diffusion field, leading to spatially propagating instabilities in the electrochemical potential which induce periodic branching during crystal growth, producing dendritic deposits. This result is interesting both as an example of control and understanding in a complex system, and as a useful combination of top-down lithography with bottom-up electrochemical self-assembly. The second part of this work focuses on the technological development of devices fabricated using this non-equilibrium electrochemical process, towards a goal of integrating a complex network as a dynamic functional component in a neuromorphic computing device. Self-assembled networks of silver nanowires were reacted with sulfur to produce interfacial "atomic switches": silver-silver sulfide junctions, which exhibit

Pregnancy after preimplantation diagnosis for a deletion in the dystrophin gene by polymerase chain reaction in embryos obtained after intracytoplasmic sperm injection

Energy Technology Data Exchange (ETDEWEB)

Lissens, W.; Liu, J.; Van Broeckhoven, C. [University Hospital, Brussels (Belgium)] [and others

1994-09-01

Duchenne muscular dystrophy (DMD) is one of the most common X-linked recessive diseases. In order to be able to perform a DMD-specific preimplantation diagnosis (PID) in a female carrier of a deletion of exons 3 to 18 in the dystrophin gene, we have developed a PCR assay to detect the deletion based on sequences of exon 17. The efficiency of this PCR was evaluated on 50 single blastomeres from 12 normal control embryos and on 41 blastomeres for 9 male and 3 female embryos from the female DMD carrier, obtained after a first preimplantation diagnosis by sexing. The exon 17 region was amplified with 100% efficiency, except in all 21 blastomeres from 6 male embryos from the carrier where no PCR signals were observed. The negative results in these blastomeres were interpreted as being found only in male embryos carrying the deletion. Intracytoplasmic sperm injection was carried out on the carrier`s metaphase II oocytes retrieved after ovarian stimulation. Embryos were analyzed for the presence of exon 17 and 2 male embryos were found to be deleted, while 4 embryos showed normal amplification signals. Three of the latter embryos were replaced, resulting in a singleton pregnancy. Amniotic cell analysis showed a normal female karyotype and DNA analysis indicated a non-carrier.

Deletion of Galgt2 (B4Galnt2) reduces muscle growth in response to acute injury and increases muscle inflammation and pathology in dystrophin-deficient mice.

Science.gov (United States)

Xu, Rui; Singhal, Neha; Serinagaoglu, Yelda; Chandrasekharan, Kumaran; Joshi, Mandar; Bauer, John A; Janssen, Paulus M L; Martin, Paul T

2015-10-01

Transgenic overexpression of Galgt2 (official name B4Galnt2) in skeletal muscle stimulates the glycosylation of α dystroglycan (αDG) and the up-regulation of laminin α2 and dystrophin surrogates known to inhibit muscle pathology in mouse models of congenital muscular dystrophy 1A and Duchenne muscular dystrophy. Skeletal muscle Galgt2 gene expression is also normally increased in the mdx mouse model of Duchenne muscular dystrophy compared with the wild-type mice. To assess whether this increased endogenous Galgt2 expression could affect disease, we quantified muscular dystrophy measures in mdx mice deleted for Galgt2 (Galgt2(-/-)mdx). Galgt2(-/-) mdx mice had increased heart and skeletal muscle pathology and inflammation, and also worsened cardiac function, relative to age-matched mdx mice. Deletion of Galgt2 in wild-type mice also slowed skeletal muscle growth in response to acute muscle injury. In each instance where Galgt2 expression was elevated (developing muscle, regenerating muscle, and dystrophic muscle), Galgt2-dependent glycosylation of αDG was also increased. Overexpression of Galgt2 failed to inhibit skeletal muscle pathology in dystroglycan-deficient muscles, in contrast to previous studies in dystrophin-deficient mdx muscles. This study demonstrates that Galgt2 gene expression and glycosylation of αDG are dynamically regulated in muscle and that endogenous Galgt2 gene expression can ameliorate the extent of muscle pathology, inflammation, and dysfunction in mdx mice. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

ANS main control complex three-dimensional computer model development

International Nuclear Information System (INIS)

Cleaves, J.E.; Fletcher, W.M.

1993-01-01

A three-dimensional (3-D) computer model of the Advanced Neutron Source (ANS) main control complex is being developed. The main control complex includes the main control room, the technical support center, the materials irradiation control room, computer equipment rooms, communications equipment rooms, cable-spreading rooms, and some support offices and breakroom facilities. The model will be used to provide facility designers and operations personnel with capabilities for fit-up/interference analysis, visual ''walk-throughs'' for optimizing maintain-ability, and human factors and operability analyses. It will be used to determine performance design characteristics, to generate construction drawings, and to integrate control room layout, equipment mounting, grounding equipment, electrical cabling, and utility services into ANS building designs. This paper describes the development of the initial phase of the 3-D computer model for the ANS main control complex and plans for its development and use

Automated complex for research of electric drives control

Science.gov (United States)

Avlasko, P. V.; Antonenko, D. A.

2018-05-01

In the article, the automated complex intended for research of various control modes of electric motors including the inductor motor of double-way feed is described. As a basis of the created complex, the National Instruments platform is chosen. The operating controller built in a platform is delivered with an operating system of real-time for creation of systems of measurement and management. The software developed in the environment of LabVIEW consists of several connected modules which are in different elements of a complex. Besides the software for automated management by experimental installation, the program complex is developed for modelling of processes in the electric drive. As a result there is an opportunity to compare simulated and received experimentally transitional characteristics of the electric drive in various operating modes.

Complexity control in statistical learning

Indian Academy of Sciences (India)

Then we describe how the method of regularization is used to control complexity in learning. We discuss two examples of regularization, one in which the function space used is finite dimensional, and another in which it is a reproducing kernel Hilbert space. Our exposition follows the formulation of Cucker and Smale.

Life-threatening Arrhythmias in a Becker Muscular Dystrophy Family due to the Duplication of Exons 3-4 of the Dystrophin Gene.

Science.gov (United States)

Ishizaki, Masatoshi; Fujimoto, Akiko; Ueyama, Hidetsugu; Nishida, Yasuto; Imamura, Shigehiro; Uchino, Makoto; Ando, Yukio

2015-01-01

We herein present a report of three patients with Becker muscular dystrophy in the same family who developed complete atrioventricular block or ventricular tachycardia with severe cardiomyopathy. Our cases became unable to walk in their teens, and were introduced to mechanical ventilation due to respiratory muscle weakness in their twenties and thirties. In all three cases, a medical device such as a permanent cardiac pacemaker or an implantable cardiac defibrillator was considered to be necessary. The duplication of exons 3-4 in the dystrophin gene was detected in two of the patients. In patients with Becker muscular dystrophy, complete atrioventricular block or ventricular tachycardia within a family has rarely been reported. Thus attention should be paid to the possibility of severe arrhythmias in the severe phenotype of Becker muscular dystrophy.

Modelling, Estimation and Control of Networked Complex Systems

CERN Document Server

Chiuso, Alessandro; Frasca, Mattia; Rizzo, Alessandro; Schenato, Luca; Zampieri, Sandro

2009-01-01

The paradigm of complexity is pervading both science and engineering, leading to the emergence of novel approaches oriented at the development of a systemic view of the phenomena under study; the definition of powerful tools for modelling, estimation, and control; and the cross-fertilization of different disciplines and approaches. This book is devoted to networked systems which are one of the most promising paradigms of complexity. It is demonstrated that complex, dynamical networks are powerful tools to model, estimate, and control many interesting phenomena, like agent coordination, synchronization, social and economics events, networks of critical infrastructures, resources allocation, information processing, or control over communication networks. Moreover, it is shown how the recent technological advances in wireless communication and decreasing in cost and size of electronic devices are promoting the appearance of large inexpensive interconnected systems, each with computational, sensing and mobile cap...

Complexity, Analysis and Control of Singular Biological Systems

CERN Document Server

Zhang, Qingling; Zhang, Xue

2012-01-01

Complexity, Analysis and Control of Singular Biological Systems follows the control of real-world biological systems at both ecological and phyisological levels concentrating on the application of now-extensively-investigated singular system theory. Much effort has recently been dedicated to the modelling and analysis of developing bioeconomic systems and the text establishes singular examples of these, showing how proper control can help to maintain sustainable economic development of biological resources. The book begins from the essentials of singular systems theory and bifurcations before tackling  the use of various forms of control in singular biological systems using examples including predator-prey relationships and viral vaccination and quarantine control. Researchers and graduate students studying the control of complex biological systems are shown how a variety of methods can be brought to bear and practitioners working with the economics of biological systems and their control will also find the ...

SU9516 Increases α7β1 Integrin and Ameliorates Disease Progression in the mdx Mouse Model of Duchenne Muscular Dystrophy.

Science.gov (United States)

Sarathy, Apurva; Wuebbles, Ryan D; Fontelonga, Tatiana M; Tarchione, Ashley R; Mathews Griner, Lesley A; Heredia, Dante J; Nunes, Andreia M; Duan, Suzann; Brewer, Paul D; Van Ry, Tyler; Hennig, Grant W; Gould, Thomas W; Dulcey, Andrés E; Wang, Amy; Xu, Xin; Chen, Catherine Z; Hu, Xin; Zheng, Wei; Southall, Noel; Ferrer, Marc; Marugan, Juan; Burkin, Dean J

2017-06-07

Duchenne muscular dystrophy (DMD) is a fatal muscle disease caused by mutations in the dystrophin gene, resulting in a complete loss of the dystrophin protein. Dystrophin is a critical component of the dystrophin glycoprotein complex (DGC), which links laminin in the extracellular matrix to the actin cytoskeleton within myofibers and provides resistance to shear stresses during muscle activity. Loss of dystrophin in DMD patients results in a fragile sarcolemma prone to contraction-induced muscle damage. The α7β1 integrin is a laminin receptor protein complex in skeletal and cardiac muscle and a major modifier of disease progression in DMD. In a muscle cell-based screen for α7 integrin transcriptional enhancers, we identified a small molecule, SU9516, that promoted increased α7β1 integrin expression. Here we show that SU9516 leads to increased α7B integrin in murine C2C12 and human DMD patient myogenic cell lines. Oral administration of SU9516 in the mdx mouse model of DMD increased α7β1 integrin in skeletal muscle, ameliorated pathology, and improved muscle function. We show that these improvements are mediated through SU9516 inhibitory actions on the p65-NF-κB pro-inflammatory and Ste20-related proline alanine rich kinase (SPAK)/OSR1 signaling pathways. This study identifies a first in-class α7 integrin-enhancing small-molecule compound with potential for the treatment of DMD. Copyright © 2017 The American Society of Gene and Cell Therapy. All rights reserved.

Metabolic remodeling agents show beneficial effects in the dystrophin-deficient mdx mouse model

Directory of Open Access Journals (Sweden)

Jahnke Vanessa E

2012-08-01

Full Text Available Abstract Background Duchenne muscular dystrophy is a genetic disease involving a severe muscle wasting that is characterized by cycles of muscle degeneration/regeneration and culminates in early death in affected boys. Mitochondria are presumed to be involved in the regulation of myoblast proliferation/differentiation; enhancing mitochondrial activity with exercise mimetics (AMPK and PPAR-delta agonists increases muscle function and inhibits muscle wasting in healthy mice. We therefore asked whether metabolic remodeling agents that increase mitochondrial activity would improve muscle function in mdx mice. Methods Twelve-week-old mdx mice were treated with two different metabolic remodeling agents (GW501516 and AICAR, separately or in combination, for 4 weeks. Extensive systematic behavioral, functional, histological, biochemical, and molecular tests were conducted to assess the drug(s' effects. Results We found a gain in body and muscle weight in all treated mice. Histologic examination showed a decrease in muscle inflammation and in the number of fibers with central nuclei and an increase in fibers with peripheral nuclei, with significantly fewer activated satellite cells and regenerating fibers. Together with an inhibition of FoXO1 signaling, these results indicated that the treatments reduced ongoing muscle damage. Conclusions The three treatments produced significant improvements in disease phenotype, including an increase in overall behavioral activity and significant gains in forelimb and hind limb strength. Our findings suggest that triggering mitochondrial activity with exercise mimetics improves muscle function in dystrophin-deficient mdx mice.

Recombinase-mediated reprogramming and dystrophin gene addition in mdx mouse induced pluripotent stem cells.

Directory of Open Access Journals (Sweden)

Chunli Zhao

Full Text Available A cell therapy strategy utilizing genetically-corrected induced pluripotent stem cells (iPSC may be an attractive approach for genetic disorders such as muscular dystrophies. Methods for genetic engineering of iPSC that emphasize precision and minimize random integration would be beneficial. We demonstrate here an approach in the mdx mouse model of Duchenne muscular dystrophy that focuses on the use of site-specific recombinases to achieve genetic engineering. We employed non-viral, plasmid-mediated methods to reprogram mdx fibroblasts, using phiC31 integrase to insert a single copy of the reprogramming genes at a safe location in the genome. We next used Bxb1 integrase to add the therapeutic full-length dystrophin cDNA to the iPSC in a site-specific manner. Unwanted DNA sequences, including the reprogramming genes, were then precisely deleted with Cre resolvase. Pluripotency of the iPSC was analyzed before and after gene addition, and ability of the genetically corrected iPSC to differentiate into myogenic precursors was evaluated by morphology, immunohistochemistry, qRT-PCR, FACS analysis, and intramuscular engraftment. These data demonstrate a non-viral, reprogramming-plus-gene addition genetic engineering strategy utilizing site-specific recombinases that can be applied easily to mouse cells. This work introduces a significant level of precision in the genetic engineering of iPSC that can be built upon in future studies.

Dramatic elevation in urinary amino terminal titin fragment excretion quantified by immunoassay in Duchenne muscular dystrophy patients and in dystrophin deficient rodents.

Science.gov (United States)

Robertson, Alan S; Majchrzak, Mark J; Smith, Courtney M; Gagnon, Robert C; Devidze, Nino; Banks, Glen B; Little, Sean C; Nabbie, Fizal; Bounous, Denise I; DiPiero, Janet; Jacobsen, Leslie K; Bristow, Linda J; Ahlijanian, Michael K; Stimpson, Stephen A

2017-07-01

Enzyme-linked and electrochemiluminescence immunoassays were developed for quantification of amino (N-) terminal fragments of the skeletal muscle protein titin (N-ter titin) and qualified for use in detection of urinary N-ter titin excretion. Urine from normal subjects contained a small but measurable level of N-ter titin (1.0 ± 0.4 ng/ml). A 365-fold increase (365.4 ± 65.0, P = 0.0001) in urinary N-ter titin excretion was seen in Duchene muscular dystrophy (DMD) patients. Urinary N-ter titin was also evaluated in dystrophin deficient rodent models. Mdx mice exhibited low urinary N-ter titin levels at 2 weeks of age followed by a robust and sustained elevation starting at 3 weeks of age, coincident with the development of systemic skeletal muscle damage in this model; fold elevation could not be determined because urinary N-ter titin was not detected in age-matched wild type mice. Levels of serum creatine kinase and serum skeletal muscle troponin I (TnI) were also low at 2 weeks, elevated at later time points and were significantly correlated with urinary N-ter titin excretion in mdx mice. Corticosteroid treatment of mdx mice resulted in improved exercise performance and lowering of both urinary N-ter titin and serum skeletal muscle TnI concentrations. Low urinary N-ter titin levels were detected in wild type rats (3.0 ± 0.6 ng/ml), while Dmd mdx rats exhibited a 556-fold increase (1652.5 ± 405.7 ng/ml, P = 0.002) (both at 5 months of age). These results suggest that urinary N-ter titin is present at low basal concentrations in normal urine and increases dramatically coincident with muscle damage produced by dystrophin deficiency. Urinary N-ter titin has potential as a facile, non-invasive and translational biomarker for DMD. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Optimization of controllability and robustness of complex networks by edge directionality

Science.gov (United States)

Liang, Man; Jin, Suoqin; Wang, Dingjie; Zou, Xiufen

2016-09-01

Recently, controllability of complex networks has attracted enormous attention in various fields of science and engineering. How to optimize structural controllability has also become a significant issue. Previous studies have shown that an appropriate directional assignment can improve structural controllability; however, the evolution of the structural controllability of complex networks under attacks and cascading has always been ignored. To address this problem, this study proposes a new edge orientation method (NEOM) based on residual degree that changes the link direction while conserving topology and directionality. By comparing the results with those of previous methods in two random graph models and several realistic networks, our proposed approach is demonstrated to be an effective and competitive method for improving the structural controllability of complex networks. Moreover, numerical simulations show that our method is near-optimal in optimizing structural controllability. Strikingly, compared to the original network, our method maintains the structural controllability of the network under attacks and cascading, indicating that the NEOM can also enhance the robustness of controllability of networks. These results alter the view of the nature of controllability in complex networks, change the understanding of structural controllability and affect the design of network models to control such networks.

Effective control of complex turbulent dynamical systems through statistical functionals.

Science.gov (United States)

Majda, Andrew J; Qi, Di

2017-05-30

Turbulent dynamical systems characterized by both a high-dimensional phase space and a large number of instabilities are ubiquitous among complex systems in science and engineering, including climate, material, and neural science. Control of these complex systems is a grand challenge, for example, in mitigating the effects of climate change or safe design of technology with fully developed shear turbulence. Control of flows in the transition to turbulence, where there is a small dimension of instabilities about a basic mean state, is an important and successful discipline. In complex turbulent dynamical systems, it is impossible to track and control the large dimension of instabilities, which strongly interact and exchange energy, and new control strategies are needed. The goal of this paper is to propose an effective statistical control strategy for complex turbulent dynamical systems based on a recent statistical energy principle and statistical linear response theory. We illustrate the potential practical efficiency and verify this effective statistical control strategy on the 40D Lorenz 1996 model in forcing regimes with various types of fully turbulent dynamics with nearly one-half of the phase space unstable.

Natural enemy interactions constrain pest control in complex agricultural landscapes.

Science.gov (United States)

Martin, Emily A; Reineking, Björn; Seo, Bumsuk; Steffan-Dewenter, Ingolf

2013-04-02

Biological control of pests by natural enemies is a major ecosystem service delivered to agriculture worldwide. Quantifying and predicting its effectiveness at large spatial scales is critical for increased sustainability of agricultural production. Landscape complexity is known to benefit natural enemies, but its effects on interactions between natural enemies and the consequences for crop damage and yield are unclear. Here, we show that pest control at the landscape scale is driven by differences in natural enemy interactions across landscapes, rather than by the effectiveness of individual natural enemy guilds. In a field exclusion experiment, pest control by flying insect enemies increased with landscape complexity. However, so did antagonistic interactions between flying insects and birds, which were neutral in simple landscapes and increasingly negative in complex landscapes. Negative natural enemy interactions thus constrained pest control in complex landscapes. These results show that, by altering natural enemy interactions, landscape complexity can provide ecosystem services as well as disservices. Careful handling of the tradeoffs among multiple ecosystem services, biodiversity, and societal concerns is thus crucial and depends on our ability to predict the functional consequences of landscape-scale changes in trophic interactions.

Improvement of cardiac contractile function by peptide-based inhibition of NF-κB in the utrophin/dystrophin-deficient murine model of muscular dystrophy

Directory of Open Access Journals (Sweden)

Guttridge Denis C

2011-05-01

Full Text Available Abstract Background Duchenne muscular dystrophy (DMD is an inherited and progressive disease causing striated muscle deterioration. Patients in their twenties generally die from either respiratory or cardiac failure. In order to improve the lifespan and quality of life of DMD patients, it is important to prevent or reverse the progressive loss of contractile function of the heart. Recent studies by our labs have shown that the peptide NBD (Nemo Binding Domain, targeted at blunting Nuclear Factor κB (NF-κB signaling, reduces inflammation, enhances myofiber regeneration, and improves contractile deficits in the diaphragm in dystrophin-deficient mdx mice. Methods To assess whether cardiac function in addition to diaphragm function can be improved, we investigated physiological and histological parameters of cardiac muscle in mice deficient for both dystrophin and its homolog utrophin (double knockout = dko mice treated with NBD peptide. These dko mice show classic pathophysiological hallmarks of heart failure, including myocyte degeneration, an impaired force-frequency response and a severely blunted β-adrenergic response. Cardiac contractile function at baseline and frequencies and pre-loads throughout the in vivo range as well as β-adrenergic reserve was measured in isolated cardiac muscle preparations. In addition, we studied histopathological and inflammatory markers in these mice. Results At baseline conditions, active force development in cardiac muscles from NBD treated dko mice was more than double that of vehicle-treated dko mice. NBD treatment also significantly improved frequency-dependent behavior of the muscles. The increase in force in NBD-treated dko muscles to β-adrenergic stimulation was robustly restored compared to vehicle-treated mice. However, histological features, including collagen content and inflammatory markers were not significantly different between NBD-treated and vehicle-treated dko mice. Conclusions We conclude

Semiotic aspects of control and modeling relations in complex systems

Energy Technology Data Exchange (ETDEWEB)

Joslyn, C.

1996-08-01

A conceptual analysis of the semiotic nature of control is provided with the goal of elucidating its nature in complex systems. Control is identified as a canonical form of semiotic relation of a system to its environment. As a form of constraint between a system and its environment, its necessary and sufficient conditions are established, and the stabilities resulting from control are distinguished from other forms of stability. These result from the presence of semantic coding relations, and thus the class of control systems is hypothesized to be equivalent to that of semiotic systems. Control systems are contrasted with models, which, while they have the same measurement functions as control systems, do not necessarily require semantic relations because of the lack of the requirement of an interpreter. A hybrid construction of models in control systems is detailed. Towards the goal of considering the nature of control in complex systems, the possible relations among collections of control systems are considered. Powers arguments on conflict among control systems and the possible nature of control in social systems are reviewed, and reconsidered based on our observations about hierarchical control. Finally, we discuss the necessary semantic functions which must be present in complex systems for control in this sense to be present at all.

Complexity Variability Assessment of Nonlinear Time-Varying Cardiovascular Control

Science.gov (United States)

Valenza, Gaetano; Citi, Luca; Garcia, Ronald G.; Taylor, Jessica Noggle; Toschi, Nicola; Barbieri, Riccardo

2017-02-01

The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier. We apply the proposed methodology to four exemplary studies involving disorders which stem from cardiology, neurology and psychiatry: Congestive Heart Failure (CHF), Major Depression Disorder (MDD), Parkinson’s Disease (PD), and Post-Traumatic Stress Disorder (PTSD) patients with insomnia under a yoga training regime. We show that complexity assessments derived from simple time-averaging are not able to discern pathology-related changes in autonomic control, and we demonstrate that between-group differences in measures of complexity variability are consistent across pathologies. Pathological states such as CHF, MDD, and PD are associated with an increased complexity variability when compared to healthy controls, whereas wellbeing derived from yoga in PTSD is associated with lower time-variance of complexity.

Practical synchronization on complex dynamical networks via optimal pinning control

Science.gov (United States)

Li, Kezan; Sun, Weigang; Small, Michael; Fu, Xinchu

2015-07-01

We consider practical synchronization on complex dynamical networks under linear feedback control designed by optimal control theory. The control goal is to minimize global synchronization error and control strength over a given finite time interval, and synchronization error at terminal time. By utilizing the Pontryagin's minimum principle, and based on a general complex dynamical network, we obtain an optimal system to achieve the control goal. The result is verified by performing some numerical simulations on Star networks, Watts-Strogatz networks, and Barabási-Albert networks. Moreover, by combining optimal control and traditional pinning control, we propose an optimal pinning control strategy which depends on the network's topological structure. Obtained results show that optimal pinning control is very effective for synchronization control in real applications.

Loss of nNOS inhibits compensatory muscle hypertrophy and exacerbates inflammation and eccentric contraction-induced damage in mdx mice

Science.gov (United States)

Froehner, Stanley C.; Reed, Sarah M.; Anderson, Kendra N.; Huang, Paul L.; Percival, Justin M.

2015-01-01

Approaches targeting nitric oxide (NO) signaling show promise as therapies for Duchenne and Becker muscular dystrophies. However, the mechanisms by which NO benefits dystrophin-deficient muscle remain unclear, but may involve nNOSβ, a newly discovered enzymatic source of NO in skeletal muscle. Here we investigate the impact of dystrophin deficiency on nNOSβ and use mdx mice engineered to lack nNOSμ and nNOSβ to discern how the loss of nNOS impacts dystrophic skeletal muscle pathology. In mdx muscle, nNOSβ was mislocalized and its association with the Golgi complex was reduced. nNOS depletion from mdx mice prevented compensatory skeletal muscle cell hypertrophy, decreased myofiber central nucleation and increased focal macrophage cell infiltration, indicating exacerbated dystrophic muscle damage. Reductions in muscle integrity in nNOS-null mdx mice were accompanied by decreases in specific force and increased susceptibility to eccentric contraction-induced muscle damage compared with mdx controls. Unexpectedly, muscle fatigue was unaffected by nNOS depletion, revealing a novel latent compensatory mechanism for the loss of nNOS in mdx mice. Together with previous studies, these data suggest that localization of both nNOSμ and nNOSβ is disrupted by dystrophin deficiency. They also indicate that nNOS has a more complex role as a modifier of dystrophic pathology and broader therapeutic potential than previously recognized. Importantly, these findings also suggest nNOSβ as a new drug target and provide a new conceptual framework for understanding nNOS signaling and the benefits of NO therapies in dystrophinopathies. PMID:25214536

Pest control of aphids depends on landscape complexity and natural enemy interactions.

Science.gov (United States)

Martin, Emily A; Reineking, Björn; Seo, Bumsuk; Steffan-Dewenter, Ingolf

2015-01-01

Aphids are a major concern in agricultural crops worldwide, and control by natural enemies is an essential component of the ecological intensification of agriculture. Although the complexity of agricultural landscapes is known to influence natural enemies of pests, few studies have measured the degree of pest control by different enemy guilds across gradients in landscape complexity. Here, we use multiple natural-enemy exclosures replicated in 18 fields across a gradient in landscape complexity to investigate (1) the strength of natural pest control across landscapes, measured as the difference between pest pressure in the presence and in the absence of natural enemies; (2) the differential contributions of natural enemy guilds to pest control, and the nature of their interactions across landscapes. We show that natural pest control of aphids increased up to six-fold from simple to complex landscapes. In the absence of pest control, aphid population growth was higher in complex than simple landscapes, but was reduced by natural enemies to similar growth rates across all landscapes. The effects of enemy guilds were landscape-dependent. Particularly in complex landscapes, total pest control was supplied by the combined contribution of flying insects and ground-dwellers. Birds had little overall impact on aphid control. Despite evidence for intraguild predation of flying insects by ground-dwellers and birds, the overall effect of enemy guilds on aphid control was complementary. Understanding pest control services at large spatial scales is critical to increase the success of ecological intensification schemes. Our results suggest that, where aphids are the main pest of concern, interactions between natural enemies are largely complementary and lead to a strongly positive effect of landscape complexity on pest control. Increasing the availability of seminatural habitats in agricultural landscapes may thus benefit not only natural enemies, but also the effectiveness of

Somatodendritic and excitatory postsynaptic distribution of neuron-type dystrophin isoform, Dp40, in hippocampal neurons.

Science.gov (United States)

Fujimoto, Takahiro; Itoh, Kyoko; Yaoi, Takeshi; Fushiki, Shinji

2014-09-12

The Duchenne muscular dystrophy (DMD) gene produces multiple dystrophin (Dp) products due to the presence of several promoters. We previously reported the existence of a novel short isoform of Dp, Dp40, in adult mouse brain. However, the exact biochemical expression profile and cytological distribution of the Dp40 protein remain unknown. In this study, we generated a polyclonal antibody against the NH2-terminal region of the Dp40 and identified the expression profile of Dp40 in the mouse brain. Through an analysis using embryonic and postnatal mouse cerebrums, we found that Dp40 emerged from the early neonatal stages until adulthood, whereas Dp71, an another Dp short isoform, was highly detected in both prenatal and postnatal cerebrums. Intriguingly, relative expressions of Dp40 and Dp71 were prominent in cultured dissociated neurons and non-neuronal cells derived from mouse hippocampus, respectively. Furthermore, the immunocytological distribution of Dp40 was analyzed in dissociated cultured neurons, revealing that Dp40 is detected in the soma and its dendrites, but not in the axon. It is worthy to note that Dp40 is localized along the subplasmalemmal region of the dendritic shafts, as well as at excitatory postsynaptic sites. Thus, Dp40 was identified as a neuron-type Dp possibly involving dendritic and synaptic functions. Copyright © 2014 Elsevier Inc. All rights reserved.

Haplotypes in the dystrophin DNA segment point to a mosaic origin of modern human diversity.

Science.gov (United States)

Zietkiewicz, Ewa; Yotova, Vania; Gehl, Dominik; Wambach, Tina; Arrieta, Isabel; Batzer, Mark; Cole, David E C; Hechtman, Peter; Kaplan, Feige; Modiano, David; Moisan, Jean-Paul; Michalski, Roman; Labuda, Damian

2003-11-01

Although Africa has played a central role in human evolutionary history, certain studies have suggested that not all contemporary human genetic diversity is of recent African origin. We investigated 35 simple polymorphic sites and one T(n) microsatellite in an 8-kb segment of the dystrophin gene. We found 86 haplotypes in 1,343 chromosomes from around the world. Although a classical out-of-Africa topology was observed in trees based on the variant frequencies, the tree of haplotype sequences reveals three lineages accounting for present-day diversity. The proportion of new recombinants and the diversity of the T(n) microsatellite were used to estimate the age of haplotype lineages and the time of colonization events. The lineage that underwent the great expansion originated in Africa prior to the Upper Paleolithic (27,000-56,000 years ago). A second group, of structurally distinct haplotypes that occupy a central position on the tree, has never left Africa. The third lineage is represented by the haplotype that lies closest to the root, is virtually absent in Africa, and appears older than the recent out-of-Africa expansion. We propose that this lineage could have left Africa before the expansion (as early as 160,000 years ago) and admixed, outside of Africa, with the expanding lineage. Contemporary human diversity, although dominated by the recently expanded African lineage, thus represents a mosaic of different contributions.

On synchronisation of a class of complex chaotic systems with complex unknown parameters via integral sliding mode control

Science.gov (United States)

Tirandaz, Hamed; Karami-Mollaee, Ali

2018-06-01

Chaotic systems demonstrate complex behaviour in their state variables and their parameters, which generate some challenges and consequences. This paper presents a new synchronisation scheme based on integral sliding mode control (ISMC) method on a class of complex chaotic systems with complex unknown parameters. Synchronisation between corresponding states of a class of complex chaotic systems and also convergence of the errors of the system parameters to zero point are studied. The designed feedback control vector and complex unknown parameter vector are analytically achieved based on the Lyapunov stability theory. Moreover, the effectiveness of the proposed methodology is verified by synchronisation of the Chen complex system and the Lorenz complex systems as the leader and the follower chaotic systems, respectively. In conclusion, some numerical simulations related to the synchronisation methodology is given to illustrate the effectiveness of the theoretical discussions.

Muscle ERRγ mitigates Duchenne muscular dystrophy via metabolic and angiogenic reprogramming.

Science.gov (United States)

Matsakas, Antonios; Yadav, Vikas; Lorca, Sabina; Narkar, Vihang

2013-10-01

Treatment of Duchenne muscular dystrophy (DMD) by replacing mutant dystrophin or restoring dystrophin-associated glycoprotein complex (DAG) has been clinically challenging. Instead, identifying and targeting muscle pathways deregulated in DMD will provide new therapeutic avenues. We report that the expression of nuclear receptor estrogen-related receptor-γ (ERRγ), and its metabolic and angiogenic targets are down-regulated (50-85%) in skeletal muscles of mdx mice (DMD model) vs. wild-type mice. Corelatively, oxidative myofibers, muscle vasculature, and exercise tolerance (33%) are decreased in mdx vs. wild-type mice. Overexpressing ERRγ selectively in the dystrophic muscles of the mdx mice restored metabolic and angiogenic gene expression compared with control mdx mice. Further, ERRγ enhanced muscle oxidative myofibers, vasculature, and blood flow (by 33-66%) and improved exercise tolerance (by 75%) in the dystrophic mice. Restoring muscle ERRγ pathway ameliorated muscle damage and also prevented DMD hallmarks of postexercise muscle damage, hypoxia, and fatigue in mdx mice. Notably, ERRγ did not restore sarcolemmal DAG complex, which is thus dispensable for antidystrophic effects of ERRγ. In summary, ERRγ-dependent metabolic and angiogenic gene program is defective in DMD, and we demonstrate that its restoration is a potential strategy for treating muscular dystrophy.

A new Main Control Room for the AGS complex

International Nuclear Information System (INIS)

Ingrassia, P.F.; Zaharatos, R.M.; Dyling, O.H.

1991-01-01

A new Main Control Room (MCR) has been built to control the accelerators of the AGS Complex. A new physical environment was produced to better control light, sound, temperature, and traffic. New control consoles were built around the work-stations that make up the distributed control system. Equipment placement within consoles and console placement within the room reflect attention to the 'human factors' needs of the operator

Advanced nuclear plant control complex

International Nuclear Information System (INIS)

Scarola, K.; Jamison, S.; Manazir, R.M.; Rescorl, R.L.; Harmon, D.L.

1991-01-01

An advanced control room complex for a nuclear power plant, including a discrete indicator and alarm system which is nuclear qualified for rapid response to changes in plant parameters and a component control system which together provide a discrete monitoring and control capability at a panel in the control room. A separate data processing system, which need not be nuclear qualified, provides integrated and overview information to the control room and to each panel, through CRTs and a large, overhead integrated process status overview board. The discrete indicator and alarm system and the data processing system receive inputs from common plant sensors and validate the sensor outputs to arrive at a representative value of the parameter for use by the operator during both normal and accidental conditions, thereby avoiding the need for him to assimilate data from each sensor individually. The integrated process status board is at the apex of an information hierarchy that extends through four levels and provides access at each panel to the full display hierarchy. The control room panels are preferably of a modular construction, permitting the definition of inputs and outputs, the man machine interface, and the plant specific algorithms, to proceed in parallel with the fabrication of the panels, the installation of the equipment and the generic testing thereof. (author)

Chaotification of complex networks with impulsive control.

Science.gov (United States)

Guan, Zhi-Hong; Liu, Feng; Li, Juan; Wang, Yan-Wu

2012-06-01

This paper investigates the chaotification problem of complex dynamical networks (CDN) with impulsive control. Both the discrete and continuous cases are studied. The method is presented to drive all states of every node in CDN to chaos. The proposed impulsive control strategy is effective for both the originally stable and unstable CDN. The upper bound of the impulse intervals for originally stable networks is derived. Finally, the effectiveness of the theoretical results is verified by numerical examples.

Optimal Control of Interdependent Epidemics in Complex Networks

OpenAIRE

Chen, Juntao; Zhang, Rui; Zhu, Quanyan

2017-01-01

Optimal control of interdependent epidemics spreading over complex networks is a critical issue. We first establish a framework to capture the coupling between two epidemics, and then analyze the system's equilibrium states by categorizing them into three classes, and deriving their stability conditions. The designed control strategy globally optimizes the trade-off between the control cost and the severity of epidemics in the network. A gradient descent algorithm based on a fixed point itera...

A new main control room for the AGS complex

International Nuclear Information System (INIS)

Ingrassia, P.F.; Zaharatos, R.M.; Dyling, O.H.

1991-01-01

A new Main Control Room (MCR) has been built to control the accelerators of the AGS Complex. A new physical environment was produced to better control light, sound, temperature, and traffic. New control consoles were built around the work-stations that make up the distributed control system. Equipment placement within consoles and console placement within the room reflect attention to the ''human factors'' needs of the operator. 1 ref., 2 figs

Integrative Genomic Analysis of In Vivo Muscle Regeneration After Severe Trauma

Science.gov (United States)

2015-11-30

muscular dystrophy and aging. The cis-regulatory networks that orchestrate in-vivo muscle repair and regeneration after traumatic injury have only been...modulates dystrophin expression: new implications for Duchenne muscular dystrophy therapy. EMBO Rep. 12, 136-141 (2011). 46. Cachiarelli, D., Martone...I. MicroRNAs involved in molecular circuitries relevant for the Duchenne muscular dystrophy pathogenesis are controlled by the dystrophin/nNOS

Finger functionality and joystick design for complex hand control

NARCIS (Netherlands)

Grinten, M.P. van der; Krause, F.

2006-01-01

Joysticks and similar multi-directional controls are increasingly applied in machines, instruments and consumer goods. Operational complexity rises through miniaturization and additional control functions on the joystick. With this the effort for the finger, hand and arm, and for the perceptive and

Physiological complexity and system adaptability: evidence from postural control dynamics of older adults.

Science.gov (United States)

Manor, Brad; Costa, Madalena D; Hu, Kun; Newton, Elizabeth; Starobinets, Olga; Kang, Hyun Gu; Peng, C K; Novak, Vera; Lipsitz, Lewis A

2010-12-01

The degree of multiscale complexity in human behavioral regulation, such as that required for postural control, appears to decrease with advanced aging or disease. To help delineate causes and functional consequences of complexity loss, we examined the effects of visual and somatosensory impairment on the complexity of postural sway during quiet standing and its relationship to postural adaptation to cognitive dual tasking. Participants of the MOBILIZE Boston Study were classified into mutually exclusive groups: controls [intact vision and foot somatosensation, n = 299, 76 ± 5 (SD) yr old], visual impairment only (Postural sway (i.e., center-of-pressure) dynamics were assessed during quiet standing and cognitive dual tasking, and a complexity index was quantified using multiscale entropy analysis. Postural sway speed and area, which did not correlate with complexity, were also computed. During quiet standing, the complexity index (mean ± SD) was highest in controls (9.5 ± 1.2) and successively lower in the visual (9.1 ± 1.1), somatosensory (8.6 ± 1.6), and combined (7.8 ± 1.3) impairment groups (P = 0.001). Dual tasking resulted in increased sway speed and area but reduced complexity (P postural sway speed from quiet standing to dual-tasking conditions. Sensory impairments contributed to decreased postural sway complexity, which reflected reduced adaptive capacity of the postural control system. Relatively low baseline complexity may, therefore, indicate control systems that are more vulnerable to cognitive and other stressors.

The Similar Structures and Control Problems of Complex Systems

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

In this paper, the naturally evolving complex systems, such as biotic and social ones, are considered. Focusing on their structures, a feature is noteworthy, i.e., the similarity in structures. The relations between the functions and behaviors of these systems and their similar structures will be studied. Owing to the management of social systems and the course of evolution of biotic systems may be regarded as control processes, the researches will be within the scope of control problems. Moreover, since it is difficult to model for biotic and social systems, it will start with the control problems of complex systems, possessing similar structures, in engineering.The obtained results show that for either linear or nonlinear systems and for a lot of control problemssimilar structures lead to a series of simplifications. In general, the original system may be decomposed into reduced amount of subsystems with lower dimensions and simpler structures. By virtue of such subsystems, the control problems of original system can be solved more simply.At last, it turns round to observe the biotic and social systems and some analyses are given.

Evolving paradigms in clinical pharmacology and therapeutics for the treatment of Duchenne muscular dystrophy.

Science.gov (United States)

Huard, J; Mu, X; Lu, A

2016-08-01

Progressive muscle weakness and degeneration due to the lack of dystrophin eventually leads to the loss of independent ambulation by the middle of the patient's second decade, and a fatal outcome due to cardiac or respiratory failure by the third decade. More specifically, loss of sarcolemmal dystrophin and the dystrophin-associated glycoprotein (DAG) complex promotes muscle fiber damage during muscle contraction. This process results in an efflux of creatine kinase (CK), an influx of calcium ions, and the recruitment of T cells, macrophages, and mast cells to the damaged muscle, causing progressive myofiber necrosis. For the last 20 years, the major goal in the development of therapeutic approaches to alleviate muscle weakness in DMD has been centered on the restoration of dystrophin or proteins that are analogous to dystrophin, such as utrophin, through a variety of modalities including cell therapy, gene therapy, gene correction, and the highly promising techniques utilizing CRISPR/Cas9 technology. Despite the development of new therapeutic options, there still exist numerous challenges that we must face with regard to these new strategies and, consequently, we still do not have any feasible options available to ultimately slow the progression of this devastating disease. The purpose of this article is to highlight the current knowledge and advancements in the evolving paradigms in clinical pharmacology and therapeutics for this devastating musculoskeletal disease. © 2016 American Society for Clinical Pharmacology and Therapeutics.

Qualitative analysis and control of complex neural networks with delays

CERN Document Server

Wang, Zhanshan; Zheng, Chengde

2016-01-01

This book focuses on the stability of the dynamical neural system, synchronization of the coupling neural system and their applications in automation control and electrical engineering. The redefined concept of stability, synchronization and consensus are adopted to provide a better explanation of the complex neural network. Researchers in the fields of dynamical systems, computer science, electrical engineering and mathematics will benefit from the discussions on complex systems. The book will also help readers to better understand the theory behind the control technique and its design.

Rescue of sarcoglycan mutations by inhibition of endoplasmic reticulum quality control is associated with minimal structural modifications.

Science.gov (United States)

Soheili, Tayebeh; Gicquel, Evelyne; Poupiot, Jérôme; N'Guyen, Luu; Le Roy, Florence; Bartoli, Marc; Richard, Isabelle

2012-02-01

Sarcoglycanopathies (SGP) are a group of autosomal recessive muscle disorders caused by primary mutations in one of the four sarcoglycan genes. The sarcoglycans (α-, β-, γ-, and δ-sarcoglycan) form a tetrameric complex at the muscle membrane that is part of the dystrophin-glycoprotein complex and plays an essential role for membrane integrity during muscle contractions. We previously showed that the most frequent missense mutation in α-sarcoglycan (p.R77C) leads to the absence of the protein at the cell membrane due to its blockade by the endoplasmic reticulum (ER) quality control. Moreover, we demonstrated that inhibition of the ER α-mannosidase I activity using kifunensine could rescue the mutant protein localization at the cell membrane. Here, we investigate 25 additional disease-causing missense mutations in the sarcoglycan genes with respect to intracellular fate and localization rescue of the mutated proteins by kifunensine. Our studies demonstrate that, similarly to p.R77C, 22 of 25 of the selected mutations lead to defective intracellular trafficking of the SGs proteins. Six of these were saved from ER retention upon kifunensine treatment. The trafficking of SGs mutants rescued by kifunensine was associated with mutations that have moderate structural impact on the protein. © 2011 Wiley Periodicals, Inc.

Nanospan, an alternatively spliced isoform of sarcospan, localizes to the sarcoplasmic reticulum in skeletal muscle and is absent in limb girdle muscular dystrophy 2F.

Science.gov (United States)

Peter, Angela K; Miller, Gaynor; Capote, Joana; DiFranco, Marino; Solares-Pérez, Alhondra; Wang, Emily L; Heighway, Jim; Coral-Vázquez, Ramón M; Vergara, Julio; Crosbie-Watson, Rachelle H

2017-06-06

Sarcospan (SSPN) is a transmembrane protein that interacts with the sarcoglycans (SGs) to form a tight subcomplex within the dystrophin-glycoprotein complex that spans the sarcolemma and interacts with laminin in the extracellular matrix. Overexpression of SSPN ameliorates Duchenne muscular dystrophy in murine models. Standard cloning approaches were used to identify nanospan, and nanospan-specific polyclonal antibodies were generated and validated. Biochemical isolation of skeletal muscle membranes and two-photon laser scanning microscopy were used to analyze nanospan localization in muscle from multiple murine models. Duchenne muscular dystrophy biopsies were analyzed by immunoblot analysis of protein lysates as well as indirect immunofluorescence analysis of muscle cryosections. Nanospan is an alternatively spliced isoform of sarcospan. While SSPN has four transmembrane domains and is a core component of the sarcolemmal dystrophin-glycoprotein complex, nanospan is a type II transmembrane protein that does not associate with the dystrophin-glycoprotein complex. We demonstrate that nanospan is enriched in the sarcoplasmic reticulum (SR) fractions and is not present in the T-tubules. SR fractions contain membranes from three distinct structural regions: a region flanking the T-tubules (triadic SR), a SR region across the Z-line (ZSR), and a longitudinal SR region across the M-line (LSR). Analysis of isolated murine muscles reveals that nanospan is mostly associated with the ZSR and triadic SR, and only minimally with the LSR. Furthermore, nanospan is absent from the SR of δ-SG-null (Sgcd -/- ) skeletal muscle, a murine model for limb girdle muscular dystrophy 2F. Analysis of skeletal muscle biopsies from Duchenne muscular dystrophy patients reveals that nanospan is preferentially expressed in type I (slow) fibers in both control and Duchenne samples. Furthermore, nanospan is significantly reduced in Duchenne biopsies. Alternative splicing of proteins from the SG

Variable structure control of complex systems analysis and design

CERN Document Server

Yan, Xing-Gang; Edwards, Christopher

2017-01-01

This book systematizes recent research work on variable-structure control. It is self-contained, presenting necessary mathematical preliminaries so that the theoretical developments can be easily understood by a broad readership. The text begins with an introduction to the fundamental ideas of variable-structure control pertinent to their application in complex nonlinear systems. In the core of the book, the authors lay out an approach, suitable for a large class of systems, that deals with system uncertainties with nonlinear bounds. Its treatment of complex systems in which limited measurement information is available makes the results developed convenient to implement. Various case-study applications are described, from aerospace, through power systems to river pollution control with supporting simulations to aid the transition from mathematical theory to engineering practicalities. The book addresses systems with nonlinearities, time delays and interconnections and considers issues such as stabilization, o...

Distance-Based Behaviors for Low-Complexity Control in Multiagent Robotics

Science.gov (United States)

Pierpaoli, Pietro

Several biological examples show that living organisms cooperate to collectively accomplish tasks impossible for single individuals. More importantly, this coordination is often achieved with a very limited set of information. Inspired by these observations, research on autonomous systems has focused on the development of distributed control techniques for control and guidance of groups of autonomous mobile agents, or robots. From an engineering perspective, when coordination and cooperation is sought in large ensembles of robotic vehicles, a reduction in hardware and algorithms' complexity becomes mandatory from the very early stages of the project design. The research for solutions capable of lowering power consumption, cost and increasing reliability are thus worth investigating. In this work, we studied low-complexity techniques to achieve cohesion and control on swarms of autonomous robots. Starting from an inspiring example with two-agents, we introduced effects of neighbors' relative positions on control of an autonomous agent. The extension of this intuition addressed the control of large ensembles of autonomous vehicles, and was applied in the form of a herding-like technique. To this end, a low-complexity distance-based aggregation protocol was defined. We first showed that our protocol produced a cohesion aggregation among the agent while avoiding inter-agent collisions. Then, a feedback leader-follower architecture was introduced for the control of the swarm. We also described how proximity measures and probability of collisions with neighbors can also be used as source of information in highly populated environments.

Complexity and dynamics of switched human balance control during quiet standing.

Science.gov (United States)

Nema, Salam; Kowalczyk, Piotr; Loram, Ian

2015-10-01

In this paper, we use a combination of numerical simulations, time series analysis, and complexity measures to investigate the dynamics of switched systems with noise, which are often used as models of human balance control during quiet standing. We link the results with complexity measures found in experimental data of human sway motion during quiet standing. The control model ensuring balance, which we use, is based on an act-and-wait control concept, that is, a human controller is switched on when a certain sway angle is reached. Otherwise, there is no active control present. Given a time series data, we determine how does it look a typical pattern of control strategy in our model system. We detect the switched nonlinearity in the system using a frequency analysis method in the absence of noise. We also analyse the effect of time delay on the existence of limit cycles in the system in the absence of noise. We perform the entropy and detrended fluctuation analyses in view of linking the switchings (and the dead zone) with the occurrences of complexity in the model system in the presence of noise. Finally, we perform the entropy and detrended fluctuation analyses on experimental data and link the results with numerical findings in our model example.

Controller Design of Complex System Based on Nonlinear Strength

Directory of Open Access Journals (Sweden)

Rongjun Mu

2015-01-01

Full Text Available This paper presents a new idea of controller design for complex systems. The nonlinearity index method was first developed for error propagation of nonlinear system. The nonlinearity indices access the boundary between the strong and the weak nonlinearities of the system model. The algorithm of nonlinearity index according to engineering application is first proposed in this paper. Applying this method on nonlinear systems is an effective way to measure the nonlinear strength of dynamics model over the full flight envelope. The nonlinearity indices access the boundary between the strong and the weak nonlinearities of system model. According to the different nonlinear strength of dynamical model, the control system is designed. The simulation time of dynamical complex system is selected by the maximum value of dynamic nonlinearity indices. Take a missile as example; dynamical system and control characteristic of missile are simulated. The simulation results show that the method is correct and appropriate.

Controlling Uncertainty Decision Making and Learning in Complex Worlds

CERN Document Server

Osman, Magda

2010-01-01

Controlling Uncertainty: Decision Making and Learning in Complex Worlds reviews and discusses the most current research relating to the ways we can control the uncertain world around us.: Features reviews and discussions of the most current research in a number of fields relevant to controlling uncertainty, such as psychology, neuroscience, computer science and engineering; Presents a new framework that is designed to integrate a variety of disparate fields of research; Represents the first book of its kind to provide a general overview of work related to understanding control

Self-Controlled Feedback for a Complex Motor Task

Directory of Open Access Journals (Sweden)

Wolf Peter

2011-12-01

Full Text Available Self-controlled augmented feedback enhances learning of simple motor tasks. Thereby, learners tend to request feedback after trials that were rated as good by themselves. Feedback after good trials promotes positive reinforcement, which enhances motor learning. The goal of this study was to investigate when naïve learners request terminal visual feedback in a complex motor task, as conclusions drawn on simple tasks can hardly be transferred to complex tasks. Indeed, seven of nine learners stated to have intended to request feedback predominantly after good trials, but in contrast to their intention, kinematic analysis showed that feedback was rather requested randomly (23% after good, 44% after intermediate, 33% after bad trials. Moreover, requesting feedback after good trials did not correlate with learning success. It seems that self-estimation of performance in complex tasks is challenging. As a consequence, learners might have focused on certain movement aspects rather than on the overall movement. Further studies should assess the current focus of the learner in detail to gain more insight in self-estimation capabilities during complex motor task learning.

The Role of Nanobiotechnology in the Study of Dystrophin and B-Dystroglycan in Membrane Stability of Aging Skeletal Muscles

Science.gov (United States)

Vaseashta, Ashok

2005-03-01

Duchene muscular dystrophy (DMD) is one of nine types of muscular dystrophy, a group of genetic degenerative diseases, primarily affecting voluntary muscles, caused by absence of dystrophin. New experiments on mice with DMD has shown that gene therapy can reverse some symptoms of the disease. The ultimate goal of gene therapy for muscle diseases is improvement of strength and function, which will require treatment in multiple muscles simultaneously. A major limitation to gene therapy until now has been that no one had found a method by which a new gene could be delivered to all the muscles of an adult animal. Recent utilization of nanotechnology to life sciences has shown exciting promises in a wide range of disciplines, showing advances in the ability to manipulate, fabricate and alter tiny subjects at the nanometer scale. In the present investigation, we have employed such techniques to study single motors such as myosin and kinesin, as well elastic proteins viz. titin and nebulin, muscle filaments, cytoskeletal filaments, and receptors in cellular membranes and cellular organelles viz. myofibril, ribosome, and chromatin. Application of AFM to images and measures the elastic properties of single monomeric and oligomeric protein, genetically engineered titin, and nebulin molecules will be presented.

Complex envelope control of pulsed accelerating fields in superconducting cavities

CERN Document Server

Czarski, T

2010-01-01

A digital control system for superconducting cavities of a linear accelerator is presented in this work. FPGA (Field Programmable Gate Arrays) based controller, managed by MATLAB, was developed to investigate a novel firmware implementation. The LLRF - Low Level Radio Frequency system for FLASH project in DESY is introduced. Essential modeling of a cavity resonator with signal and power analysis is considered as a key approach to the control methods. An electrical model is represented by the non-stationary state space equation for the complex envelope of the cavity voltage driven by the current generator and the beam loading. The electromechanical model of the superconducting cavity resonator including the Lorentz force detuning has been developed for a simulation purpose. The digital signal processing is proposed for the field vector detection. The field vector sum control is considered for multiple cavities driven by one klystron. An algebraic, complex domain model is proposed for the system analysis. The c...

The method of measurement and synchronization control for large-scale complex loading system

International Nuclear Information System (INIS)

Liao Min; Li Pengyuan; Hou Binglin; Chi Chengfang; Zhang Bo

2012-01-01

With the development of modern industrial technology, measurement and control system was widely used in high precision, complex industrial control equipment and large-tonnage loading device. The measurement and control system is often used to analyze the distribution of stress and displacement in the complex bearing load or the complex nature of the mechanical structure itself. In ITER GS mock-up with 5 flexible plates, for each load combination, detect and measure potential slippage between the central flexible plate and the neighboring spacers is necessary as well as the potential slippage between each pre-stressing bar and its neighboring plate. The measurement and control system consists of seven sets of EDC controller and board, computer system, 16-channel quasi-dynamic strain gauge, 25 sets of displacement sensors, 7 sets of load and displacement sensors in the cylinders. This paper demonstrates the principles and methods of EDC220 digital controller to achieve synchronization control, and R and D process of multi-channel loading control software and measurement software. (authors)

Complexity and Automation Displays of Air Traffic Control: Literature Review and Analysis

National Research Council Canada - National Science Library

Xing, Jing; Manning, Carol A

2005-01-01

This report reviewed a number of measures of complexity associated with visual displays and analyzed the potential to apply these methods to assess the complexity of air traffic control (ATC) displays...

Improved safety in advanced control complexes, without side effects

International Nuclear Information System (INIS)

Harmon, D.L.

1997-01-01

If we only look for a moment at the world around us, it is obvious that advances in digital electronic equipment and Human-System Interface (HSI) technology are occurring at a phenomenal pace. This is evidenced from our home entertainment systems to the dashboard and computer-based operation of our new cars. Though the nuclear industry has less vigorously embraced these advances, their application is being implemented through individual upgrades to current generation nuclear plants and as plant-wide control complexes for advanced plants. In both venues modem technology possesses widely touted advantages for improving plant availability as well as safety. The well-documented safety benefits of digital Instrumentation and Controls (I ampersand C) include higher reliability resulting from redundancy and fault tolerance, inherent self-test and self-diagnostic capabilities which have replaced error-prone human tasks, resistance to setpoint drift increasing available operating margins, and the ability to run complex, real-time, computer-based algorithms directly supporting an operator's monitoring and control task requirements. 22 refs., 3 figs., 5 tabs

Metabolic dysfunction and altered mitochondrial dynamics in the utrophin-dystrophin deficient mouse model of duchenne muscular dystrophy.

Directory of Open Access Journals (Sweden)

Meghna Pant

Full Text Available The utrophin-dystrophin deficient (DKO mouse model has been widely used to understand the progression of Duchenne muscular dystrophy (DMD. However, it is unclear as to what extent muscle pathology affects metabolism. Therefore, the present study was focused on understanding energy expenditure in the whole animal and in isolated extensor digitorum longus (EDL muscle and to determine changes in metabolic enzymes. Our results show that the 8 week-old DKO mice consume higher oxygen relative to activity levels. Interestingly the EDL muscle from DKO mouse consumes higher oxygen per unit integral force, generates less force and performs better in the presence of pyruvate thus mimicking a slow twitch muscle. We also found that the expression of hexokinase 1 and pyruvate kinase M2 was upregulated several fold suggesting increased glycolytic flux. Additionally, there is a dramatic increase in dynamin-related protein 1 (Drp 1 and mitofusin 2 protein levels suggesting increased mitochondrial fission and fusion, a feature associated with increased energy demand and altered mitochondrial dynamics. Collectively our studies point out that the dystrophic disease has caused significant changes in muscle metabolism. To meet the increased energetic demand, upregulation of metabolic enzymes and regulators of mitochondrial fusion and fission is observed in the dystrophic muscle. A better understanding of the metabolic demands and the accompanied alterations in the dystrophic muscle can help us design improved intervention therapies along with existing drug treatments for the DMD patients.

Regularization and Complexity Control in Feed-forward Networks

OpenAIRE

Bishop, C. M.

1995-01-01

In this paper we consider four alternative approaches to complexity control in feed-forward networks based respectively on architecture selection, regularization, early stopping, and training with noise. We show that there are close similarities between these approaches and we argue that, for most practical applications, the technique of regularization should be the method of choice.

Novel pinning control strategies for synchronisation of complex networks with nonlinear coupling dynamics

International Nuclear Information System (INIS)

Zhao-Bing, Liu; Hua-Guang, Zhang; Qiu-Ye, Sun

2010-01-01

This paper considers the global stability of controlling an uncertain complex network to a homogeneous trajectory of the uncoupled system by a local pinning control strategy. Several sufficient conditions are derived to guarantee the network synchronisation by investigating the relationship among pinning synchronisation, network topology, and coupling strength. Also, some fundamental and yet challenging problems in the pinning control of complex networks are discussed: (1) what nodes should be selected as pinned candidates? (2) How many nodes are needed to be pinned for a fixed coupling strength? Furthermore, an adaptive pinning control scheme is developed. In order to achieve synchronisation of an uncertain complex network, the adaptive tuning strategy of either the coupling strength or the control gain is utilised. As an illustrative example, a network with the Lorenz system as node self-dynamics is simulated to verify the efficacy of theoretical results. (general)

A rare subclinical or mild type of Becker muscular dystrophy caused by a single exon 48 deletion of the dystrophin gene.

Science.gov (United States)

Zimowski, Janusz G; Pilch, Jacek; Pawelec, Magdalena; Purzycka, Joanna K; Kubalska, Jolanta; Ziora-Jakutowicz, Karolina; Dudzińska, Magdalena; Zaremba, Jacek

2017-08-01

In the material of 227 families with Becker muscular dystrophy (BMD), we found nine non-consanguineous families with 17 male individuals carrying a rare mutation-a single exon 48 deletion of the dystrophin gene-who were affected with a very mild or subclinical form of BMD. They were usually detected thanks to accidental findings of elevated serum creatine phosphokinase (sCPK). A thorough clinical analysis of the carriers, both children (12) and adults (5), revealed in some of them muscle hypotonia (10/17) and/or very mild muscle weakness (9/17), as well as decreased tendon reflexes (6/17). Adults, apart from very mild muscle weakness and calf hypertrophy in some, had no significant abnormalities on neurological assessments and had good exercise tolerance. Parents of the children carriers of the exon 48 deletion are usually unaware of their children being affected, and possibly at risk of developing life-threatening cardiomyopathy. The same concerns the adult male carriers. Therefore, the authors postulate undertaking preventive measures such as cascade screening of the relatives of the probands. Newborn screening programmes of Duchenne muscular dystrophy (DMD)/BMD based on sCPK marked increase may be considered.

Control of complex dynamics and chaos in distributed parameter systems

Energy Technology Data Exchange (ETDEWEB)

Chakravarti, S.; Marek, M.; Ray, W.H. [Univ. of Wisconsin, Madison, WI (United States)

1995-12-31

This paper discusses a methodology for controlling complex dynamics and chaos in distributed parameter systems. The reaction-diffusion system with Brusselator kinetics, where the torus-doubling or quasi-periodic (two characteristic incommensurate frequencies) route to chaos exists in a defined range of parameter values, is used as an example. Poincare maps are used for characterization of quasi-periodic and chaotic attractors. The dominant modes or topos, which are inherent properties of the system, are identified by means of the Singular Value Decomposition. Tested modal feedback control schemas based on identified dominant spatial modes confirm the possibility of stabilization of simple quasi-periodic trajectories in the complex quasi-periodic or chaotic spatiotemporal patterns.

Morpholino oligomer-mediated exon skipping averts the onset of dystrophic pathology in the mdx mouse.

Science.gov (United States)

Fletcher, Sue; Honeyman, Kaite; Fall, Abbie M; Harding, Penny L; Johnsen, Russell D; Steinhaus, Joshua P; Moulton, Hong M; Iversen, Patrick L; Wilton, Stephen D

2007-09-01

Duchenne and Becker muscular dystrophies are allelic disorders arising from mutations in the dystrophin gene. Duchenne muscular dystrophy is characterized by an absence of functional protein, whereas Becker muscular dystrophy, commonly caused by in-frame deletions, shows synthesis of partially functional protein. Anti-sense oligonucleotides can induce specific exon removal during processing of the dystrophin primary transcript, while maintaining or restoring the reading frame, and thereby overcome protein-truncating mutations. The mdx mouse has a non-sense mutation in exon 23 of the dystrophin gene that precludes functional dystrophin production, and this model has been used in the development of treatment strategies for dystrophinopathies. A phosphorodiamidate morpholino oligomer (PMO) has previously been shown to exclude exon 23 from the dystrophin gene transcript and induce dystrophin expression in the mdxmouse, in vivo and in vitro. In this report, a cell-penetrating peptide (CPP)-conjugated oligomer targeted to the mouse dystrophin exon 23 donor splice site was administered to mdxmice by intraperitoneal injection. We demonstrate dystrophin expression and near-normal muscle architecture in all muscles examined, except for cardiac muscle. The CPP greatly enhanced uptake of the PMO, resulting in widespread dystrophin expression.

Dynamic behavior and chaos control in a complex Riccati-type map ...

African Journals Online (AJOL)

This paper is devoted to analyze the dynamic behavior of a Riccati- type map with complex variables and complex parameters. Fixed points and their asymptotic stability are studied. Lyapunov exponent is computed to indicate chaos. Bifurcation and chaos are discussed. Chaotic behavior of the map has been controlled by ...

Complexity of verifying nonblockingness in modular supervisory control

Czech Academy of Sciences Publication Activity Database

Masopust, Tomáš

2018-01-01

Roč. 63, č. 2 (2018), s. 602-607 ISSN 0018-9286 Institutional support: RVO:67985840 Keywords : nonblockingness * modular supervisory control * complexity Subject RIV: BA - General Mathematics OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 4.270, year: 2016 http://ieeexplore.ieee.org/document/7979596/

Scalable Harmonization of Complex Networks With Local Adaptive Controllers

Czech Academy of Sciences Publication Activity Database

Kárný, Miroslav; Herzallah, R.

2017-01-01

Roč. 47, č. 3 (2017), s. 394-404 ISSN 2168-2216 R&D Projects: GA ČR GA13-13502S Institutional support: RVO:67985556 Keywords : Adaptive control * Adaptive estimation * Bayes methods * Complex networks * Decentralized control * Fee dback * Fee dforward systems * Recursive estimation Subject RIV: BB - Applied Statistics, Operational Research OBOR OECD: Statistics and probability Impact factor: 2.350, year: 2016 http://library.utia.cas.cz/separaty/2016/AS/karny-0457337.pdf

Intelligent Transportation Control based on Proactive Complex Event Processing

OpenAIRE

Wang Yongheng; Geng Shaofeng; Li Qian

2016-01-01

Complex Event Processing (CEP) has become the key part of Internet of Things (IoT). Proactive CEP can predict future system states and execute some actions to avoid unwanted states which brings new hope to intelligent transportation control. In this paper, we propose a proactive CEP architecture and method for intelligent transportation control. Based on basic CEP technology and predictive analytic technology, a networked distributed Markov decision processes model with predicting states is p...

Differential expression of Dystroglycan-spliceforms with and without the mucin-like domain during Drosophila embryogenesis

DEFF Research Database (Denmark)

Schneider, Martina; Baumgartner, Stefan

2008-01-01

Dystroglycan (DG) is a widely expressed extracellular matrix (ECM) receptor required for muscle viability, synaptogenesis, basement-membrane formation and epithelial development. As an integral component of the Dystrophin-associated glycoprotein complex, DG plays a central role in linking the ECM...

Calibration, monitoring, and control of complex detector systems

International Nuclear Information System (INIS)

Breidenbach, M.

1981-01-01

LEP detectors will probably be complex devices having tens of subsystems; some subsystems having perhaps tens of thousands of channels. Reasonable design goals for such a detector will include economic use of money and people, rapid and reliable calibration and monitoring of the detector, and simple control and operation of the device. The synchronous operation of an e + e - storage ring, coupled with its relatively low interaction rate, allow the design of simple circuits for time and charge measurements. These circuits, and more importantly, the basic detector channels, can usually be tested and calibrated by signal injection into the detector. Present detectors utilize semi-autonomous controllers which collect such calibration data and calculate statistics as well as control sparse data scans. Straightforward improvements in programming technology should move the entire calibration into these local controllers, so that calibration and testing time will be a constant independent of the number of channels in a system. Considerable programming effort may be saved by emphasizing the similarities of the subsystems, so that the subsystems can be described by a reasonable database and general purpose calibration and test routines can be used. Monitoring of the apparatus will probably continue to be of two classes: 'passive' histogramming of channel occupancies and other more complex combinations of the data; and 'active' injection of test patterns and calibration signals during a run. The relative importance of active monitoring will increase for the low data rates expected off resonances at high s. Experience at SPEAR and PEP is used to illustrate these approaches. (Auth.)

Calibration, Monitoring, and Control of Complex Detector Systems

Science.gov (United States)

Breidenbach, M.

1981-04-01

LEP Detectors will probably be complex devices having tens of subsystems; some subsystems having perhaps tens of thousands of channels. Reasonable design goals for such a detector will include economic use of money and people, rapid and reliable calibration and monitoring of the detector, and simple control and operation of the device. The synchronous operation of an e+e- storage ring, coupled with its relatively low interaction rate, allow the design of simple circuits for time and charge measurements. These circuits, and more importantly, the basic detector channels, can usually be tested and calibrated by signal injection into the detector. Present detectors utilize semi-autonomous controllers which collect such calibration data and calculate statistics as well as control sparse data scans. Straightforward improvements in programming technology should move the entire calibration into these local controllers, so that calibration and testing time will be a constant independent of the number of channels in a system. Considerable programming effort may be saved by emphasizing the similarities of the subsystems, so that the subsystems can be described by a reasonable database and general purpose calibration and test routines can be used. Monitoring of the apparatus will probably continue to be of two classes: "passive" histogramming of channel occupancies and other more complex combinations of the data; and "active" injection of test patterns and calibration signals during a run. The relative importance of active monitoring will increase for the low data rates expected off resonances at high s. Experience at SPEAR and PEP is used to illustrate these approaches.

Genetic diagnosis of Duchenne and Becker muscular dystrophy using next-generation sequencing technology: comprehensive mutational search in a single platform.

Science.gov (United States)

Lim, Byung Chan; Lee, Seungbok; Shin, Jong-Yeon; Kim, Jong-Il; Hwang, Hee; Kim, Ki Joong; Hwang, Yong Seung; Seo, Jeong-Sun; Chae, Jong Hee

2011-11-01

Duchenne muscular dystrophy or Becker muscular dystrophy might be a suitable candidate disease for application of next-generation sequencing in the genetic diagnosis because the complex mutational spectrum and the large size of the dystrophin gene require two or more analytical methods and have a high cost. The authors tested whether large deletions/duplications or small mutations, such as point mutations or short insertions/deletions of the dystrophin gene, could be predicted accurately in a single platform using next-generation sequencing technology. A custom solution-based target enrichment kit was designed to capture whole genomic regions of the dystrophin gene and other muscular-dystrophy-related genes. A multiplexing strategy, wherein four differently bar-coded samples were captured and sequenced together in a single lane of the Illumina Genome Analyser, was applied. The study subjects were 25 16 with deficient dystrophin expression without a large deletion/duplication and 9 with a known large deletion/duplication. Nearly 100% of the exonic region of the dystrophin gene was covered by at least eight reads with a mean read depth of 107. Pathogenic small mutations were identified in 15 of the 16 patients without a large deletion/duplication. Using these 16 patients as the standard, the authors' method accurately predicted the deleted or duplicated exons in the 9 patients with known mutations. Inclusion of non-coding regions and paired-end sequence analysis enabled accurate identification by increasing the read depth and providing information about the breakpoint junction. The current method has an advantage for the genetic diagnosis of Duchenne muscular dystrophy and Becker muscular dystrophy wherein a comprehensive mutational search may be feasible using a single platform.

NAD+ biosynthesis ameliorates a zebrafish model of muscular dystrophy.

Directory of Open Access Journals (Sweden)

Michelle F Goody

Full Text Available Muscular dystrophies are common, currently incurable diseases. A subset of dystrophies result from genetic disruptions in complexes that attach muscle fibers to their surrounding extracellular matrix microenvironment. Cell-matrix adhesions are exquisite sensors of physiological conditions and mediate responses that allow cells to adapt to changing conditions. Thus, one approach towards finding targets for future therapeutic applications is to identify cell adhesion pathways that mediate these dynamic, adaptive responses in vivo. We find that nicotinamide riboside kinase 2b-mediated NAD+ biosynthesis, which functions as a small molecule agonist of muscle fiber-extracellular matrix adhesion, corrects dystrophic phenotypes in zebrafish lacking either a primary component of the dystrophin-glycoprotein complex or integrin alpha7. Exogenous NAD+ or a vitamin precursor to NAD+ reduces muscle fiber degeneration and results in significantly faster escape responses in dystrophic embryos. Overexpression of paxillin, a cell adhesion protein downstream of NAD+ in this novel cell adhesion pathway, reduces muscle degeneration in zebrafish with intact integrin receptors but does not improve motility. Activation of this pathway significantly increases organization of laminin, a major component of the extracellular matrix basement membrane. Our results indicate that the primary protective effects of NAD+ result from changes to the basement membrane, as a wild-type basement membrane is sufficient to increase resilience of dystrophic muscle fibers to damage. The surprising result that NAD+ supplementation ameliorates dystrophy in dystrophin-glycoprotein complex- or integrin alpha7-deficient zebrafish suggests the existence of an additional laminin receptor complex that anchors muscle fibers to the basement membrane. We find that integrin alpha6 participates in this pathway, but either integrin alpha7 or the dystrophin-glycoprotein complex is required in conjunction

Reversible immortalisation enables genetic correction of human muscle progenitors and engineering of next-generation human artificial chromosomes for Duchenne muscular dystrophy.

Science.gov (United States)

Benedetti, Sara; Uno, Narumi; Hoshiya, Hidetoshi; Ragazzi, Martina; Ferrari, Giulia; Kazuki, Yasuhiro; Moyle, Louise Anne; Tonlorenzi, Rossana; Lombardo, Angelo; Chaouch, Soraya; Mouly, Vincent; Moore, Marc; Popplewell, Linda; Kazuki, Kanako; Katoh, Motonobu; Naldini, Luigi; Dickson, George; Messina, Graziella; Oshimura, Mitsuo; Cossu, Giulio; Tedesco, Francesco Saverio

2018-02-01

Transferring large or multiple genes into primary human stem/progenitor cells is challenged by restrictions in vector capacity, and this hurdle limits the success of gene therapy. A paradigm is Duchenne muscular dystrophy (DMD), an incurable disorder caused by mutations in the largest human gene: dystrophin. The combination of large-capacity vectors, such as human artificial chromosomes (HACs), with stem/progenitor cells may overcome this limitation. We previously reported amelioration of the dystrophic phenotype in mice transplanted with murine muscle progenitors containing a HAC with the entire dystrophin locus (DYS-HAC). However, translation of this strategy to human muscle progenitors requires extension of their proliferative potential to withstand clonal cell expansion after HAC transfer. Here, we show that reversible cell immortalisation mediated by lentivirally delivered excisable hTERT and Bmi1 transgenes extended cell proliferation, enabling transfer of a novel DYS-HAC into DMD satellite cell-derived myoblasts and perivascular cell-derived mesoangioblasts. Genetically corrected cells maintained a stable karyotype, did not undergo tumorigenic transformation and retained their migration ability. Cells remained myogenic in vitro (spontaneously or upon MyoD induction) and engrafted murine skeletal muscle upon transplantation. Finally, we combined the aforementioned functions into a next-generation HAC capable of delivering reversible immortalisation, complete genetic correction, additional dystrophin expression, inducible differentiation and controllable cell death. This work establishes a novel platform for complex gene transfer into clinically relevant human muscle progenitors for DMD gene therapy. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

Gamma-sarcoglycan is required for the response of archvillin to mechanical stimulation in skeletal muscle

Science.gov (United States)

Spinazzola, Janelle M.; Smith, Tara C.; Liu, Min; Luna, Elizabeth J.; Barton, Elisabeth R.

2015-01-01

Loss of gamma-sarcoglycan (γ-SG) induces muscle degeneration and signaling defects in response to mechanical load, and its absence is common to both Duchenne and limb girdle muscular dystrophies. Growing evidence suggests that aberrant signaling contributes to the disease pathology; however, the mechanisms of γ-SG-mediated mechanical signaling are poorly understood. To uncover γ-SG signaling pathway components, we performed yeast two-hybrid screens and identified the muscle-specific protein archvillin as a γ-SG and dystrophin interacting protein. Archvillin protein and message levels were significantly upregulated at the sarcolemma of murine γ-SG-null (gsg−/−) muscle but delocalized in dystrophin-deficient mdx muscle. Similar elevation of archvillin protein was observed in human quadriceps muscle lacking γ-SG. Reintroduction of γ-SG in gsg−/− muscle by rAAV injection restored archvillin levels to that of control C57 muscle. In situ eccentric contraction of tibialis anterior (TA) muscles from C57 mice caused ERK1/2 phosphorylation, nuclear activation of P-ERK1/2 and stimulus-dependent archvillin association with P-ERK1/2. In contrast, TA muscles from gsg−/− and mdx mice exhibited heightened P-ERK1/2 and increased nuclear P-ERK1/2 localization following eccentric contractions, but the archvillin–P-ERK1/2 association was completely ablated. These results position archvillin as a mechanically sensitive component of the dystrophin complex and demonstrate that signaling defects caused by loss of γ-SG occur both at the sarcolemma and in the nucleus. PMID:25605665

CERN Proton Synchrotron Complex High-Level Controls Renovation

CERN Document Server

Deghaye, S; Garcia Quintas, D; Gourber-Pace, M; Kruk, G; Kulikova, O; Lezhebokov, V; Pasinelli, S; Peryt, M; Roderick, C; Roux, E; Sobczak, M; Steerenberg, R; Wozniak, J; Zaharieva, Z

2009-01-01

After a detailed study of the Proton Synchrotron (PS) complex requirements by experts of CERN controls & operation groups, a proposal to develop a new system, called Injector Controls Architecture (InCA), was presented to and accepted by the management late 2007. Aiming at the homogenisation of the control systems across CERN accelerators, InCA is based on components developed for the Large Hadron Collider (LHC) but also new components required to fulfil operation needs. In 2008, the project was in its elaboration phase and we successfully validated its architecture and critical use-cases during several machine development sessions. After description of the architecture put in place and the components used, this paper describes the planning approach taken combining iterative development phases with deployment in operation for validation sessions.

The conserved WW-domain binding sites in Dystroglycan C-terminus are essential but partially redundant for Dystroglycan function

Directory of Open Access Journals (Sweden)

Deng W-M

2009-02-01

Full Text Available Abstract Background Dystroglycan (Dg is a transmembrane protein that is a part of the Dystrophin Glycoprotein Complex (DGC which connects the extracellular matrix to the actin cytoskeleton. The C-terminal end of Dg contains a number of putative SH3, SH2 and WW domain binding sites. The most C-terminal PPXY motif has been established as a binding site for Dystrophin (Dys WW-domain. However, our previous studies indicate that both Dystroglycan PPXY motives, WWbsI and WWbsII can bind Dystrophin protein in vitro. Results We now find that both WW binding sites are important for maintaining full Dg function in the establishment of oocyte polarity in Drosophila. If either WW binding site is mutated, the Dg protein can still be active. However, simultaneous mutations in both WW binding sites abolish the Dg activities in both overexpression and loss-of-function oocyte polarity assays in vivo. Additionally, sequence comparisons of WW binding sites in 12 species of Drosophila, as well as in humans, reveal a high level of conservation. This preservation throughout evolution supports the idea that both WW binding sites are functionally required. Conclusion Based on the obtained results we propose that the presence of the two WW binding sites in Dystroglycan secures the essential interaction between Dg and Dys and might further provide additional regulation for the cytoskeletal interactions of this complex.

Linkage disequilibria among (CA){sub n} polymorphisms in the human dystrophin gene and their implications in carrier detection and prenatal diagnosis in Duchenne and Becker musclar dystrophies

Energy Technology Data Exchange (ETDEWEB)

Chakraborty, R.; Zhong, Y.; Andrade, M. de [Univ. of Texas Graduate School of Biomedical Sciences, Houston, TX (United States)] [and others

1994-06-01

Four short tandem repeat loci, characterized by length polymorphisms of (CA){sub n} repeats, have been detected within introns 44, 45, 49, and 50 of the human dystrophin gene. The predicted heterozygosites for these loci range from 72 to 93%, and observed allele numbers range from 6 to 19 in 57 normal chromosomes, revealing their high degree of polymorphism. Evidence for significant disequilibria between the loci within introns 49 and 50 is found. These data appear to be consistent with observations of recombination frequencies between these markers and the length of the intron 44 in relation to the entire region. In addition, these four loci are collectively found to be 100% informative in carrier detection/prenatal diagnosis of Becker and Duchenne muscular dystrophies (B/DMD), whereas scoring the (CA){sub n} markers within introns 45 and 49 alone gives a 99.6% success rate. 13 refs., 4 tabs.

Voluntary wheel running in dystrophin-deficient (mdx) mice: Relationships between exercise parameters and exacerbation of the dystrophic phenotype.

Science.gov (United States)

Smythe, Gayle M; White, Jason D

2011-12-18

Voluntary wheel running can potentially be used to exacerbate the disease phenotype in dystrophin-deficient mdx mice. While it has been established that voluntary wheel running is highly variable between individuals, the key parameters of wheel running that impact the most on muscle pathology have not been examined in detail. We conducted a 2-week test of voluntary wheel running by mdx mice and the impact of wheel running on disease pathology. There was significant individual variation in the average daily distance (ranging from 0.003 ± 0.005 km to 4.48 ± 0.96 km), culminating in a wide range (0.040 km to 67.24 km) of total cumulative distances run by individuals. There was also variation in the number and length of run/rest cycles per night, and the average running rate. Correlation analyses demonstrated that in the quadriceps muscle, a low number of high distance run/rest cycles was the most consistent indicator for increased tissue damage. The amount of rest time between running bouts was a key factor associated with gastrocnemius damage. These data emphasize the need for detailed analysis of individual running performance, consideration of the length of wheel exposure time, and the selection of appropriate muscle groups for analysis, when applying the use of voluntary wheel running to disease exacerbation and/or pre-clinical testing of the efficacy of therapeutic agents in the mdx mouse.

Optimal Control of Complex Systems Based on Improved Dual Heuristic Dynamic Programming Algorithm

Directory of Open Access Journals (Sweden)

Hui Li

2017-01-01

Full Text Available When applied to solving the data modeling and optimal control problems of complex systems, the dual heuristic dynamic programming (DHP technique, which is based on the BP neural network algorithm (BP-DHP, has difficulty in prediction accuracy, slow convergence speed, poor stability, and so forth. In this paper, a dual DHP technique based on Extreme Learning Machine (ELM algorithm (ELM-DHP was proposed. Through constructing three kinds of network structures, the paper gives the detailed realization process of the DHP technique in the ELM. The controller designed upon the ELM-DHP algorithm controlled a molecular distillation system with complex features, such as multivariability, strong coupling, and nonlinearity. Finally, the effectiveness of the algorithm is verified by the simulation that compares DHP and HDP algorithms based on ELM and BP neural network. The algorithm can also be applied to solve the data modeling and optimal control problems of similar complex systems.

Controlling Uncertainty: A Review of Human Behavior in Complex Dynamic Environments

Science.gov (United States)

Osman, Magda

2010-01-01

Complex dynamic control (CDC) tasks are a type of problem-solving environment used for examining many cognitive activities (e.g., attention, control, decision making, hypothesis testing, implicit learning, memory, monitoring, planning, and problem solving). Because of their popularity, there have been many findings from diverse domains of research…

Intelligent Transportation Control based on Proactive Complex Event Processing

Directory of Open Access Journals (Sweden)

Wang Yongheng

2016-01-01

Full Text Available Complex Event Processing (CEP has become the key part of Internet of Things (IoT. Proactive CEP can predict future system states and execute some actions to avoid unwanted states which brings new hope to intelligent transportation control. In this paper, we propose a proactive CEP architecture and method for intelligent transportation control. Based on basic CEP technology and predictive analytic technology, a networked distributed Markov decision processes model with predicting states is proposed as sequential decision model. A Q-learning method is proposed for this model. The experimental evaluations show that this method works well when used to control congestion in in intelligent transportation systems.

Controlling Magnetism of a Complex Metallic System Using Atomic Individualism

Science.gov (United States)

Mudryk, Y.; Paudyal, D.; Pecharsky, V. K.; Gschneidner, K. A., Jr.; Misra, S.; Miller, G. J.

2010-08-01

When the complexity of a metallic compound reaches a certain level, a specific location in the structure may be critically responsible for a given fundamental property of a material while other locations may not play as much of a role in determining such a property. The first-principles theory has pinpointed a critical location in the framework of a complex intermetallic compound—Gd5Ge4—that resulted in a controlled alteration of the magnetism of this compound using precise chemical tools.

Design process and philosophy of TVA's latest advance control room complex

International Nuclear Information System (INIS)

Owens, G.R.; Masters, D.W.

1979-01-01

TVA's latest nuclear power plant control room design includes a greater emphasis on human factors as compared to their earlier plant designs. This emphasis has resulted in changes in the overall design philosophy and design process. This paper discusses some of the prominent design features of both the control room and the surrounding control room complex. In addition, it also presents some of the important activities involved in the process of developing the advanced control room design

Optimal control of complex atomic quantum systems.

Science.gov (United States)

van Frank, S; Bonneau, M; Schmiedmayer, J; Hild, S; Gross, C; Cheneau, M; Bloch, I; Pichler, T; Negretti, A; Calarco, T; Montangero, S

2016-10-11

Quantum technologies will ultimately require manipulating many-body quantum systems with high precision. Cold atom experiments represent a stepping stone in that direction: a high degree of control has been achieved on systems of increasing complexity. However, this control is still sub-optimal. In many scenarios, achieving a fast transformation is crucial to fight against decoherence and imperfection effects. Optimal control theory is believed to be the ideal candidate to bridge the gap between early stage proof-of-principle demonstrations and experimental protocols suitable for practical applications. Indeed, it can engineer protocols at the quantum speed limit - the fastest achievable timescale of the transformation. Here, we demonstrate such potential by computing theoretically and verifying experimentally the optimal transformations in two very different interacting systems: the coherent manipulation of motional states of an atomic Bose-Einstein condensate and the crossing of a quantum phase transition in small systems of cold atoms in optical lattices. We also show that such processes are robust with respect to perturbations, including temperature and atom number fluctuations.

Synchronizing and controlling hyperchaos in complex Lorentz-Haken systems

International Nuclear Information System (INIS)

Fang Jinqing

1995-03-01

Synchronizing hyperchaos is realized by the drive-response relationship in the complex Lorentz-Haken system and its higher-order cascading systems for the first time. Controlling hyperchaos is achieved by the intermittent proportional feedback to all of the drive (master) system variables. The complex Lorentz-Haken system describes the detuned single-mode laser and is taken as a typical example of hyperchaotic synchronization to clarify our ideas and results. The ideas and concepts could be extended to some nonlinear dynamical systems and have prospects for potential applications, for example. to laser, electronics, plasma, cryptography, communication, chemical and biological systems and so on. (8 figs., 2 tabs.)

Synchronizing and controlling hyperchaos in complex Lorentz-Haken systems

Energy Technology Data Exchange (ETDEWEB)

Jinqing, Fang [Academia Sinica, Beijing, BJ (China). Inst. of Atomic Energy

1995-03-01

Synchronizing hyperchaos is realized by the drive-response relationship in the complex Lorentz-Haken system and its higher-order cascading systems for the first time. Controlling hyperchaos is achieved by the intermittent proportional feedback to all of the drive (master) system variables. The complex Lorentz-Haken system describes the detuned single-mode laser and is taken as a typical example of hyperchaotic synchronization to clarify our ideas and results. The ideas and concepts could be extended to some nonlinear dynamical systems and have prospects for potential applications, for example. to laser, electronics, plasma, cryptography, communication, chemical and biological systems and so on. (8 figs., 2 tabs.).

The impulsive control synchronization of the drive-response complex system

International Nuclear Information System (INIS)

Zhao Yanhong; Yang Yongqing

2008-01-01

This Letter investigates projective synchronization between the drive system and response complex dynamical system. An impulsive control scheme is adapted to synchronize the drive-response dynamical system to a desired scalar factor. By using the stability theory of the impulsive differential equation, the criteria for the projective synchronization are derived. The feasibility of the impulsive control of the projective synchronization is demonstrated in the drive-response dynamical system

Exponential synchronization of complex delayed dynamical networks via pinning periodically intermittent control

Energy Technology Data Exchange (ETDEWEB)

Cai Shuiming, E-mail: caishuiming2008@yahoo.com.c [Department of Mathematics, Shanghai University, Shanghai 200444 (China); Institute of System Biology, Shanghai University, Shanghai 200444 (China); Hao Junjun [Institute of System Biology, Shanghai University, Shanghai 200444 (China); He, Qinbin [Department of Mathematics, Taizhou University, Linhai 317000 (China); Institute of System Biology, Shanghai University, Shanghai 200444 (China); Liu Zengrong, E-mail: zrongliu@126.co [Department of Mathematics, Shanghai University, Shanghai 200444 (China) and Institute of System Biology, Shanghai University, Shanghai 200444 (China)

2011-05-09

The problem of synchronization for a class of complex delayed dynamical networks via pinning periodically intermittent control is considered in this Letter. Some novel and useful exponential synchronization criteria are obtained by utilizing the methods which are different from the techniques employed in the existing works, and the derived results are less conservative. Especially, the traditional assumptions on control width and time delays are released in our results. Moreover, a pinning scheme deciding what nodes should be chosen as pinned candidates and how many nodes are needed to be pinned for a fixed coupling strength is provided. A Barabasi-Albert network example is finally given to illustrate the effectiveness of the theoretical results. - Highlights: Pinning control problem of complex networks via intermittent control is investigated. The traditional assumptions on control width and time delays are removed. A scheme deciding what nodes should be chosen as pinned candidates is proposed. A scheme deciding how many nodes are needed to be pinned is provided.

Cell division control by the Chromosomal Passenger Complex

Energy Technology Data Exchange (ETDEWEB)

Waal, Maike S. van der; Hengeveld, Rutger C.C.; Horst, Armando van der; Lens, Susanne M.A., E-mail: s.m.a.lens@umcutrecht.nl

2012-07-15

The Chromosomal Passenger Complex (CPC) consisting of Aurora B kinase, INCENP, Survivin and Borealin, is essential for genomic stability by controlling multiple processes during both nuclear and cytoplasmic division. In mitosis it ensures accurate segregation of the duplicated chromosomes by regulating the mitotic checkpoint, destabilizing incorrectly attached spindle microtubules and by promoting the axial shortening of chromosomal arms in anaphase. During cytokinesis the CPC most likely prevents chromosome damage by imposing an abscission delay when a chromosome bridge connects the two daughter cells. Moreover, by controlling proper cytoplasmic division, the CPC averts tetraploidization. This review describes recent insights on how the CPC is capable of conducting its various functions in the dividing cell to ensure chromosomal stability.

Mental Models and the Control of Actions in Complex Environments

DEFF Research Database (Denmark)

Rasmussen, Jens

1987-01-01

of human activities. The need for analysis of complex work scenarios is discussed, together with the necessity of considering several levels of cognitive control depending upon different kinds of internal representations. The development of mental representations during learning and adaptation...

Early-progressive dilated cardiomyopathy in a family with Becker muscular dystrophy related to a novel frameshift mutation in the dystrophin gene exon 27.

Science.gov (United States)

Tsuda, Takeshi; Fitzgerald, Kristi; Scavena, Mena; Gidding, Samuel; Cox, Mary O; Marks, Harold; Flanigan, Kevin M; Moore, Steven A

2015-03-01

We report a family in which two male siblings with Becker muscular dystrophy (BMD) developed severe dilated cardiomyopathy (DCM) and progressive heart failure (HF) at age 11 years; one died at age 14 years while awaiting heart transplant and the other underwent left ventricular assist device implantation at the same age. Genetic analysis of one sibling showed a novel frameshift mutation in exon 27 of Duchenne muscular dystrophy (DMD) gene (c.3779_3785delCTTTGGAinsGG), in which seven base pairs are deleted and two are inserted. Although this predicts an amino-acid substitution and premature termination (p.Thr1260Argfs*8), muscle biopsy dystrophin immunostaining instead indicates that the mutation is more likely to alter splicing. Despite relatively preserved skeletal muscular performance, both the siblings developed progressive HF secondary to early-onset DCM. In addition, their 7-year-old nephew with delayed gross motor development, mild proximal muscle weakness and markedly elevated serum creatine kinase level (>13 000 IU l(-1)) at 16 months was recently demonstrated to have the familial DMD mutation. Here, we report a novel genotype of BMD with early-onset DCM and progressive lethal HF during early adolescence.

Lower extremity fatigue increases complexity of postural control during a single-legged stance

Directory of Open Access Journals (Sweden)

Bailey Jerry J

2011-08-01

Full Text Available Abstract Background Non-linear approaches to assessment of postural control can provide insight that compliment linear approaches. Control entropy (CE is a recently developed statistical tool from non-linear dynamical systems used to assess the complexity of non-stationary signals. We have previously used CE of high resolution accelerometry in running to show decreased complexity with exhaustive exercise. The purpose of this study was to determine if complexity of postural control decreases following fatiguing exercise using CE. Methods Ten subjects (5 M/5 F; 25 ± 3 yr; 169.4 ± 11.7 cm; 79.0 ± 16.9 kg consented to participation approved by Western Oregon University IRB and completed two trials separated by 2-7 days. Trials consisted of two single-legged balance tests separated by two Wingate anaerobic tests (WAnT; PreFat/PostFat, or rest period (PreRest/PostRest. Balance tests consisted of a series of five single-legged stances, separated by 30 s rest, performed while standing on the dominant leg for 15-s with the participant crossing the arms over the chest and flexing the non-dominant knee to 90 degrees. High resolution accelerometers (HRA were fixed superficial to L3/L4 at the approximate center of mass (COM. Triaxial signals from the HRA were streamed in real time at 625 Hz. COM accelerations were recorded in g's for vertical (VT, medial/lateral (ML, and anterior/posterior (AP axes. A newly developed statistic (R-test was applied to group response shapes generated by Karhunen Loeve (KL transform modes resulting from Control Entropy (CE analysis. Results R-tests showed a significant mean vector difference (p p p p Conclusions These data indicate that fatiguing exercise eliminates the differential complexity response between axes, but increases complexity in all axes compared to the non-fatigued condition. This has implications with regard to the effects of fatigue on strategies of the control system to maintain postural control.

Dmdmdx/Largemyd: a new mouse model of neuromuscular diseases useful for studying physiopathological mechanisms and testing therapies

Directory of Open Access Journals (Sweden)

Poliana C. M. Martins

2013-09-01

Although muscular dystrophies are among the most common human genetic disorders, there are few treatment options available. Animal models have become increasingly important for testing new therapies prior to entering human clinical trials. The Dmdmdx mouse is the most widely used animal model for Duchenne muscular dystrophy (DMD, presenting the same molecular and protein defect as seen in humans with the disease. However, this mouse is not useful for clinical trials because of its very mild phenotype. The mouse model for congenital myodystrophy type 1D, Largemyd, harbors a mutation in the glycosyltransferase Large gene and displays a severe phenotype. To help elucidate the role of the proteins dystrophin and LARGE in the organization of the dystrophin-glycoprotein complex in muscle sarcolemma, we generated double-mutant mice for the dystrophin and LARGE proteins. The new Dmdmdx/Largemyd mouse model is viable and shows a severe phenotype that is associated with the lack of dystrophin in muscle. We tested the usefulness of our new mouse model for cell therapy by systemically injecting them with normal murine mesenchymal adipose stem cells (mASCs. We verified that the mASCs were hosted in the dystrophic muscle. The new mouse model has proven to be very useful for the study of several other therapies, because injected cells can be screened both through DNA and protein analysis. Study of its substantial muscle weakness will also be very informative in the evaluation of functional benefits of these therapies.

NAD+ Biosynthesis Ameliorates a Zebrafish Model of Muscular Dystrophy

Science.gov (United States)

Goody, Michelle F.; Kelly, Meghan W.; Reynolds, Christine J.; Khalil, Andre; Crawford, Bryan D.; Henry, Clarissa A.

2012-01-01

Muscular dystrophies are common, currently incurable diseases. A subset of dystrophies result from genetic disruptions in complexes that attach muscle fibers to their surrounding extracellular matrix microenvironment. Cell-matrix adhesions are exquisite sensors of physiological conditions and mediate responses that allow cells to adapt to changing conditions. Thus, one approach towards finding targets for future therapeutic applications is to identify cell adhesion pathways that mediate these dynamic, adaptive responses in vivo. We find that nicotinamide riboside kinase 2b-mediated NAD+ biosynthesis, which functions as a small molecule agonist of muscle fiber-extracellular matrix adhesion, corrects dystrophic phenotypes in zebrafish lacking either a primary component of the dystrophin-glycoprotein complex or integrin alpha7. Exogenous NAD+ or a vitamin precursor to NAD+ reduces muscle fiber degeneration and results in significantly faster escape responses in dystrophic embryos. Overexpression of paxillin, a cell adhesion protein downstream of NAD+ in this novel cell adhesion pathway, reduces muscle degeneration in zebrafish with intact integrin receptors but does not improve motility. Activation of this pathway significantly increases organization of laminin, a major component of the extracellular matrix basement membrane. Our results indicate that the primary protective effects of NAD+ result from changes to the basement membrane, as a wild-type basement membrane is sufficient to increase resilience of dystrophic muscle fibers to damage. The surprising result that NAD+ supplementation ameliorates dystrophy in dystrophin-glycoprotein complex– or integrin alpha7–deficient zebrafish suggests the existence of an additional laminin receptor complex that anchors muscle fibers to the basement membrane. We find that integrin alpha6 participates in this pathway, but either integrin alpha7 or the dystrophin-glycoprotein complex is required in conjunction with integrin

Controlling collective dynamics in complex minority-game resource-allocation systems

Science.gov (United States)

Zhang, Ji-Qiang; Huang, Zi-Gang; Dong, Jia-Qi; Huang, Liang; Lai, Ying-Cheng

2013-05-01

Resource allocation takes place in various kinds of real-world complex systems, such as traffic systems, social services institutions or organizations, or even ecosystems. The fundamental principle underlying complex resource-allocation dynamics is Boolean interactions associated with minority games, as resources are generally limited and agents tend to choose the least used resource based on available information. A common but harmful dynamical behavior in resource-allocation systems is herding, where there are time intervals during which a large majority of the agents compete for a few resources, leaving many other resources unused. Accompanying the herd behavior is thus strong fluctuations with time in the number of resources being used. In this paper, we articulate and establish that an intuitive control strategy, namely pinning control, is effective at harnessing the herding dynamics. In particular, by fixing the choices of resources for a few agents while leaving the majority of the agents free, herding can be eliminated completely. Our investigation is systematic in that we consider random and targeted pinning and a variety of network topologies, and we carry out a comprehensive analysis in the framework of mean-field theory to understand the working of control. The basic philosophy is then that, when a few agents waive their freedom to choose resources by receiving sufficient incentives, the majority of the agents benefit in that they will make fair, efficient, and effective use of the available resources. Our work represents a basic and general framework to address the fundamental issue of fluctuations in complex dynamical systems with significant applications to social, economical, and political systems.

Criteria for the design of the control room complex for a nuclear power generating station

International Nuclear Information System (INIS)

Anon.

1981-01-01

This Standard addresses the central control room of a nuclear power generating station and the overall complex in which this room is housed. It is not intended to cover special or normally unattended control rooms, such as those provided for radioactive waste handling or for emergency shutdown operations. The nuclear power generating station control room complex provides a protective envelope for plant operating personnel and for instrument and control equipment vital to the operation of the plant during normal and abnormal conditions. In this capacity, the control room complex must be designed and constructed to meet the following criteria contained in Appendix A of 10CFR50, General Design criteria for Nuclear Power Plants: (1) Criterion 2: design bases for protection against natural phenomena; (2) Criterion 3: fire protection; (3) Criterion 4: environmental and missile design bases; (4) Criterion 5: sharing of structures, systems and components (multiunit stations only); and (5) Criterion 19: control room

A Probabilistic Approach to Control of Complex Systems and Its Application to Real-Time Pricing

Directory of Open Access Journals (Sweden)

Koichi Kobayashi

2014-01-01

Full Text Available Control of complex systems is one of the fundamental problems in control theory. In this paper, a control method for complex systems modeled by a probabilistic Boolean network (PBN is studied. A PBN is widely used as a model of complex systems such as gene regulatory networks. For a PBN, the structural control problem is newly formulated. In this problem, a discrete probability distribution appeared in a PBN is controlled by the continuous-valued input. For this problem, an approximate solution method using a matrix-based representation for a PBN is proposed. Then, the problem is approximated by a linear programming problem. Furthermore, the proposed method is applied to design of real-time pricing systems of electricity. Electricity conservation is achieved by appropriately determining the electricity price over time. The effectiveness of the proposed method is presented by a numerical example on real-time pricing systems.

The conserved WW-domain binding sites in Dystroglycan C-terminus are essential but partially redundant for Dystroglycan function

DEFF Research Database (Denmark)

Yatsenko, A S; Kucherenko, M M; Pantoja, M

2009-01-01

BACKGROUND: Dystroglycan (Dg) is a transmembrane protein that is a part of the Dystrophin Glycoprotein Complex (DGC) which connects the extracellular matrix to the actin cytoskeleton. The C-terminal end of Dg contains a number of putative SH3, SH2 and WW domain binding sites. The most C...

Complex fluid network optimization and control integrative design based on nonlinear dynamic model

International Nuclear Information System (INIS)

Sui, Jinxue; Yang, Li; Hu, Yunan

2016-01-01

In view of distribution according to complex fluid network’s needs, this paper proposed one optimization computation method of the nonlinear programming mathematical model based on genetic algorithm. The simulation result shows that the overall energy consumption of the optimized fluid network has a decrease obviously. The control model of the fluid network is established based on nonlinear dynamics. We design the control law based on feedback linearization, take the optimal value by genetic algorithm as the simulation data, can also solve the branch resistance under the optimal value. These resistances can provide technical support and reference for fluid network design and construction, so can realize complex fluid network optimization and control integration design.

Model-Based Development and Evaluation of Control for Complex Multi-Domain Systems

DEFF Research Database (Denmark)

Grujic, Ivan; Nilsson, Rene

A Cyber-Physical System (CPS) incorporates sensing, actuating, computing and communicative capabilities, which are often combined to control the system. The development of CPSs poses a challenge, since the complexity of the physical system dynamics must be taken into account when designing...... Unmanned Aerial Vehicle (UAV) has been constructed and used to develop an attitude controller based on Model Predictive Control (MPC). The MPC controller has been compared to an existing open source Proportional Integral Derivative (PID) attitude controller. This thesis contributes to the discipline...

Adaptive Synchronization of Fractional Order Complex-Variable Dynamical Networks via Pinning Control

Science.gov (United States)

Ding, Da-Wei; Yan, Jie; Wang, Nian; Liang, Dong

2017-09-01

In this paper, the synchronization of fractional order complex-variable dynamical networks is studied using an adaptive pinning control strategy based on close center degree. Some effective criteria for global synchronization of fractional order complex-variable dynamical networks are derived based on the Lyapunov stability theory. From the theoretical analysis, one concludes that under appropriate conditions, the complex-variable dynamical networks can realize the global synchronization by using the proper adaptive pinning control method. Meanwhile, we succeed in solving the problem about how much coupling strength should be applied to ensure the synchronization of the fractional order complex networks. Therefore, compared with the existing results, the synchronization method in this paper is more general and convenient. This result extends the synchronization condition of the real-variable dynamical networks to the complex-valued field, which makes our research more practical. Finally, two simulation examples show that the derived theoretical results are valid and the proposed adaptive pinning method is effective. Supported by National Natural Science Foundation of China under Grant No. 61201227, National Natural Science Foundation of China Guangdong Joint Fund under Grant No. U1201255, the Natural Science Foundation of Anhui Province under Grant No. 1208085MF93, 211 Innovation Team of Anhui University under Grant Nos. KJTD007A and KJTD001B, and also supported by Chinese Scholarship Council

The semiotics of control and modeling relations in complex systems.

Science.gov (United States)

Joslyn, C

2001-01-01

We provide a conceptual analysis of ideas and principles from the systems theory discourse which underlie Pattee's semantic or semiotic closure, which is itself foundational for a school of theoretical biology derived from systems theory and cybernetics, and is now being related to biological semiotics and explicated in the relational biological school of Rashevsky and Rosen. Atomic control systems and models are described as the canonical forms of semiotic organization, sharing measurement relations, but differing topologically in that control systems are circularly and models linearly related to their environments. Computation in control systems is introduced, motivating hierarchical decomposition, hybrid modeling and control systems, and anticipatory or model-based control. The semiotic relations in complex control systems are described in terms of relational constraints, and rules and laws are distinguished as contingent and necessary functional entailments, respectively. Finally, selection as a meta-level of constraint is introduced as the necessary condition for semantic relations in control systems and models.

Pinning synchronization of two general complex networks with periodically intermittent control

Directory of Open Access Journals (Sweden)

Meng Fanyu

2015-12-01

Full Text Available In this paper, the method of periodically pinning intermittent control is introduced to solve the problem of outer synchronization between two complex networks. Based on the Lyapunov stability theory, differential inequality method and adaptive technique, some simple synchronous criteria have been derived analytically. At last, both the theoretical and numerical analysis illustrate the effectiveness of the proposed control methodology. This method not only reduces the conservatism of control gain but also saves the cost of production.These advantages make this method having a large application scope in the real production process.

Complexity control in statistical learning

Indian Academy of Sciences (India)

complexity of the class of models from which we are to choose our model. In this ... As is explained in §2, we use the concept of covering numbers to quantify the complexity of a class of ..... called structural risk minimization (SRM). Vapnik ...

Muscle synergies and complexity of neuromuscular control during gait in cerebral palsy.

Science.gov (United States)

Steele, Katherine M; Rozumalski, Adam; Schwartz, Michael H

2015-12-01

Individuals with cerebral palsy (CP) have impaired movement due to a brain injury near birth. Understanding how neuromuscular control is altered in CP can provide insight into pathological movement. We sought to determine if individuals with CP demonstrate reduced complexity of neuromuscular control during gait compared with unimpaired individuals and if changes in control are related to functional ability. Muscle synergies during gait were retrospectively analyzed for 633 individuals (age range 3.9-70y): 549 with CP (hemiplegia, n=122; diplegia, n=266; triplegia, n=73; quadriplegia, n=88) and 84 unimpaired individuals. Synergies were calculated using non-negative matrix factorization from surface electromyography collected during previous clinical gait analyses. Synergy complexity during gait was compared with diagnosis subtype, functional ability, and clinical examination measures. Fewer synergies were required to describe muscle activity during gait in individuals with CP compared with unimpaired individuals. Changes in synergies were related to functional impairment and clinical examination measures including selective motor control, strength, and spasticity. Individuals with CP use a simplified control strategy during gait compared with unimpaired individuals. These results were similar to synergies during walking among adult stroke survivors, suggesting similar neuromuscular control strategies between these clinical populations. © 2015 Mac Keith Press.

The impact of treatment complexity and computer-control delivery technology on treatment delivery errors

International Nuclear Information System (INIS)

Fraass, Benedick A.; Lash, Kathy L.; Matrone, Gwynne M.; Volkman, Susan K.; McShan, Daniel L.; Kessler, Marc L.; Lichter, Allen S.

1998-01-01

Purpose: To analyze treatment delivery errors for three-dimensional (3D) conformal therapy performed at various levels of treatment delivery automation and complexity, ranging from manual field setup to virtually complete computer-controlled treatment delivery using a computer-controlled conformal radiotherapy system (CCRS). Methods and Materials: All treatment delivery errors which occurred in our department during a 15-month period were analyzed. Approximately 34,000 treatment sessions (114,000 individual treatment segments [ports]) on four treatment machines were studied. All treatment delivery errors logged by treatment therapists or quality assurance reviews (152 in all) were analyzed. Machines 'M1' and 'M2' were operated in a standard manual setup mode, with no record and verify system (R/V). MLC machines 'M3' and 'M4' treated patients under the control of the CCRS system, which (1) downloads the treatment delivery plan from the planning system; (2) performs some (or all) of the machine set up and treatment delivery for each field; (3) monitors treatment delivery; (4) records all treatment parameters; and (5) notes exceptions to the electronically-prescribed plan. Complete external computer control is not available on M3; therefore, it uses as many CCRS features as possible, while M4 operates completely under CCRS control and performs semi-automated and automated multi-segment intensity modulated treatments. Analysis of treatment complexity was based on numbers of fields, individual segments, nonaxial and noncoplanar plans, multisegment intensity modulation, and pseudoisocentric treatments studied for a 6-month period (505 patients) concurrent with the period in which the delivery errors were obtained. Treatment delivery time was obtained from the computerized scheduling system (for manual treatments) or from CCRS system logs. Treatment therapists rotate among the machines; therefore, this analysis does not depend on fixed therapist staff on particular

Assembly and control of large microtubule complexes

Science.gov (United States)

Korolev, Kirill; Ishihara, Keisuke; Mitchison, Timothy

Motility, division, and other cellular processes require rapid assembly and disassembly of microtubule structures. We report a new mechanism for the formation of asters, radial microtubule complexes found in very large cells. The standard model of aster growth assumes elongation of a fixed number of microtubules originating from the centrosomes. However, aster morphology in this model does not scale with cell size, and we found evidence for microtubule nucleation away from centrosomes. By combining polymerization dynamics and auto-catalytic nucleation of microtubules, we developed a new biophysical model of aster growth. The model predicts an explosive transition from an aster with a steady-state radius to one that expands as a travelling wave. At the transition, microtubule density increases continuously, but aster growth rate discontinuously jumps to a nonzero value. We tested our model with biochemical perturbations in egg extract and confirmed main theoretical predictions including the jump in the growth rate. Our results show that asters can grow even though individual microtubules are short and unstable. The dynamic balance between microtubule collapse and nucleation could be a general framework for the assembly and control of large microtubule complexes. NIH GM39565; Simons Foundation 409704; Honjo International 486 Scholarship Foundation.

Managerial span of control: a pilot study comparing departmental complexity and number of direct reports.

Science.gov (United States)

Merrill, Katreena Collette; Pepper, Ginette; Blegen, Mary

2013-09-01

Nurse managers play pivotal roles in hospitals. However, restructuring has resulted in nurse managers having wider span of control and reduced visibility. The purpose of this pilot study was to compare two methods of measuring span of control: departmental complexity and number of direct reports. Forty-one nurse managers across nine hospitals completed The Ottawa Hospital Clinical Manager Span of Control Tool (TOH-SOC) and a demographic survey. A moderate positive relationship between number of direct reports and departmental complexity score was identified (r=.49, p=managers' responsibility. Copyright © 2013 Longwoods Publishing.

Presynaptic dystroglycan-pikachurin complex regulates the proper synaptic connection between retinal photoreceptor and bipolar cells.

Science.gov (United States)

Omori, Yoshihiro; Araki, Fumiyuki; Chaya, Taro; Kajimura, Naoko; Irie, Shoichi; Terada, Koji; Muranishi, Yuki; Tsujii, Toshinori; Ueno, Shinji; Koyasu, Toshiyuki; Tamaki, Yasuhiro; Kondo, Mineo; Amano, Shiro; Furukawa, Takahisa

2012-05-02

Dystroglycan (DG) is a key component of the dystrophin-glycoprotein complex (DGC) at the neuromuscular junction postsynapse. In the mouse retina, the DGC is localized at the presynapse of photoreceptor cells, however, the function of presynaptic DGC is poorly understood. Here, we developed and analyzed retinal photoreceptor-specific DG conditional knock-out (DG CKO) mice. We found that the DG CKO retina showed a reduced amplitude and a prolonged implicit time of the ERG b-wave. Electron microscopic analysis revealed that bipolar dendrite invagination into the photoreceptor terminus is perturbed in the DG CKO retina. In the DG CKO retina, pikachurin, a DG ligand in the retina, is markedly decreased at photoreceptor synapses. Interestingly, in the Pikachurin(-/-) retina, the DG signal at the ribbon synaptic terminus was severely reduced, suggesting that pikachurin is required for the presynaptic accumulation of DG at the photoreceptor synaptic terminus, and conversely DG is required for pikachurin accumulation. Furthermore, we found that overexpression of pikachurin induces formation and clustering of a DG-pikachurin complex on the cell surface. The Laminin G repeats of pikachurin, which are critical for its oligomerization and interaction with DG, were essential for the clustering of the DG-pikachurin complex as well. These results suggest that oligomerization of pikachurin and its interaction with DG causes DG assembly on the synapse surface of the photoreceptor synaptic terminals. Our results reveal that the presynaptic interaction of pikachurin with DG at photoreceptor terminals is essential for both the formation of proper photoreceptor ribbon synaptic structures and normal retinal electrophysiology.

DMD and BMD in the same family due to two distinct mutations

Energy Technology Data Exchange (ETDEWEB)

Morandi, L.; Mora, M.; Di Blasi, C.; Brugnoni, R. [National Inst. C. Besta, Milan (Italy)] [and others

1995-12-04

We report on a family with a boy affected by Duchenne muscular dystrophy (DMD) and an asymptomatic cousin with a Becker-type dystrophin abnormality, diagnosed by chance. Dystrophin gene analysis showed that these conditions were caused by two distinct deletions with breakpoints in different exons. In Xp21 families, DNA analysis and dystrophin testing of asymptomatic males with high CK plasma levels might detect different dystrophin mutations in separate haplotypes as in our family, although we stress there should be clear clinical or familial indications for such testing. 24 refs., 5 figs.

Complex system modelling and control through intelligent soft computations

CERN Document Server

Azar, Ahmad

2015-01-01

The book offers a snapshot of the theories and applications of soft computing in the area of complex systems modeling and control. It presents the most important findings discussed during the 5th International Conference on Modelling, Identification and Control, held in Cairo, from August 31-September 2, 2013. The book consists of twenty-nine selected contributions, which have been thoroughly reviewed and extended before their inclusion in the volume. The different chapters, written by active researchers in the field, report on both current theories and important applications of soft-computing. Besides providing the readers with soft-computing fundamentals, and soft-computing based inductive methodologies/algorithms, the book also discusses key industrial soft-computing applications, as well as multidisciplinary solutions developed for a variety of purposes, like windup control, waste management, security issues, biomedical applications and many others. It is a perfect reference guide for graduate students, r...

Architecture of built-in microcontrollers in the U-70 complex control system

International Nuclear Information System (INIS)

Balakin, S.I.; Voevodin, V.P.; Inchagov, A.A.; Komarov, V.V.

2000-01-01

The distributed system of built-in microcontrollers (BMS) for functional control of supply sources of magnetooptical elements is created within the frames of works on modernization of the U-70 control complex. The BMS architecture and functional diagram of one of them are presented. The microcontrollers operation algorithm is based on the eventuation principle. The BMS basic parameters are presented [ru

Targeting artificial transcription factors to the utrophin A promoter: effects on dystrophic pathology and muscle function.

Science.gov (United States)

Lu, Yifan; Tian, Chai; Danialou, Gawiyou; Gilbert, Rénald; Petrof, Basil J; Karpati, George; Nalbantoglu, Josephine

2008-12-12

Duchenne muscular dystrophy is caused by a genetic defect in the dystrophin gene. The absence of dystrophin results in muscle fiber necrosis and regeneration, leading to progressive muscle fiber loss. Utrophin is a close analogue of dystrophin. A substantial, ectopic expression of utrophin in the extrasynaptic sarcolemma of dystrophin-deficient muscle fibers can prevent deleterious effects of dystrophin deficiency. An alternative approach for the extrasynaptic up-regulation of utrophin involves the augmentation of utrophin transcription via the endogenous utrophin A promoter using custom-designed transcriptional activator proteins with zinc finger (ZFP) motifs. We tested a panel of custom-designed ZFP for their ability to activate the utrophin A promoter. Expression of one such ZFP efficiently increased, in a time-dependent manner, utrophin transcript and protein levels both in vitro and in vivo. In dystrophic mouse (mdx) muscles, administration of adenoviral vectors expressing this ZFP led to significant enhancement of muscle function with decreased necrosis, restoration of the dystrophin-associated proteins, and improved resistance to eccentric contractions. These studies provide evidence that specifically designed ZFPs can act as strong transcriptional activators of the utrophin A promoter. These may thus serve as attractive therapeutic agents for dystrophin deficiency states such as Duchenne muscular dystrophy.

Automated information and control complex of hydro-gas endogenous mine processes

Science.gov (United States)

Davkaev, K. S.; Lyakhovets, M. V.; Gulevich, T. M.; Zolin, K. A.

2017-09-01

The automated information and control complex designed to prevent accidents, related to aerological situation in the underground workings, accounting of the received and handed over individual devices, transmission and display of measurement data, and the formation of preemptive solutions is considered. Examples for the automated workplace of an airgas control operator by individual means are given. The statistical characteristics of field data characterizing the aerological situation in the mine are obtained. The conducted studies of statistical characteristics confirm the feasibility of creating a subsystem of controlled gas distribution with an adaptive arrangement of points for gas control. The adaptive (multivariant) algorithm for processing measuring information of continuous multidimensional quantities and influencing factors has been developed.

Effect of interaction strength on robustness of controlling edge dynamics in complex networks

Science.gov (United States)

Pang, Shao-Peng; Hao, Fei

2018-05-01

Robustness plays a critical role in the controllability of complex networks to withstand failures and perturbations. Recent advances in the edge controllability show that the interaction strength among edges plays a more important role than network structure. Therefore, we focus on the effect of interaction strength on the robustness of edge controllability. Using three categories of all edges to quantify the robustness, we develop a universal framework to evaluate and analyze the robustness in complex networks with arbitrary structures and interaction strengths. Applying our framework to a large number of model and real-world networks, we find that the interaction strength is a dominant factor for the robustness in undirected networks. Meanwhile, the strongest robustness and the optimal edge controllability in undirected networks can be achieved simultaneously. Different from the case of undirected networks, the robustness in directed networks is determined jointly by the interaction strength and the network's degree distribution. Moreover, a stronger robustness is usually associated with a larger number of driver nodes required to maintain full control in directed networks. This prompts us to provide an optimization method by adjusting the interaction strength to optimize the robustness of edge controllability.

Pinning control of complex networked systems synchronization, consensus and flocking of networked systems via pinning

CERN Document Server

Su, Housheng

2013-01-01

Synchronization, consensus and flocking are ubiquitous requirements in networked systems. Pinning Control of Complex Networked Systems investigates these requirements by using the pinning control strategy, which aims to control the whole dynamical network with huge numbers of nodes by imposing controllers for only a fraction of the nodes. As the direct control of every node in a dynamical network with huge numbers of nodes might be impossible or unnecessary, it’s then very important to use the pinning control strategy for the synchronization of complex dynamical networks. The research on pinning control strategy in consensus and flocking of multi-agent systems can not only help us to better understand the mechanisms of natural collective phenomena, but also benefit applications in mobile sensor/robot networks. This book offers a valuable resource for researchers and engineers working in the fields of control theory and control engineering.   Housheng Su is an Associate Professor at the Department of Contro...

Control system for a heavy-ion accelerator complex K4 - K10

International Nuclear Information System (INIS)

Kotov, V.M.; Pose, R.

1992-01-01

Control systems for newly created accelerators, perhaps for the first time, may be designed almost only around international standards for communication and control techniques. This is also true for the project of a control system for the accelerator complex K4-K10 at the Joint Institute for Nuclear Research Dubna. Nevertheless, open systems architecture with construction principles being essential for modern systems of such big devices as particle accelerators leaves designers enough possibilities for solving even very sophisticated problems. (author)

The database for accelerator control in the CERN PS Complex

International Nuclear Information System (INIS)

Cuperus, J.H.

1987-01-01

The use of a database started 7 years ago and is an effort to separate logic from data so that programs and routines can do a larger number of operations on data structures without knowing a priori the contents of these structures. It is of great help in coping with the complexities of a system controlling many linked accelerators and storage rings

Integrated health management and control of complex dynamical systems

Science.gov (United States)

Tolani, Devendra K.

2005-11-01

A comprehensive control and health management strategy for human-engineered complex dynamical systems is formulated for achieving high performance and reliability over a wide range of operation. Results from diverse research areas such as Probabilistic Robust Control (PRC), Damage Mitigating/Life Extending Control (DMC), Discrete Event Supervisory (DES) Control, Symbolic Time Series Analysis (STSA) and Health and Usage Monitoring System (HUMS) have been employed to achieve this goal. Continuous-domain control modules at the lower level are synthesized by PRC and DMC theories, whereas the upper-level supervision is based on DES control theory. In the PRC approach, by allowing different levels of risk under different flight conditions, the control system can achieve the desired trade off between stability robustness and nominal performance. In the DMC approach, component damage is incorporated in the control law to reduce the damage rate for enhanced structural durability. The DES controller monitors the system performance and, based on the mission requirements (e.g., performance metrics and level of damage mitigation), switches among various lower-level controllers. The core idea is to design a framework where the DES controller at the upper-level, mimics human intelligence and makes appropriate decisions to satisfy mission requirements, enhance system performance and structural durability. Recently developed tools in STSA have been used for anomaly detection and failure prognosis. The DMC deals with the usage monitoring or operational control part of health management, where as the issue of health monitoring is addressed by the anomaly detection tools. The proposed decision and control architecture has been validated on two test-beds, simulating the operations of rotorcraft dynamics and aircraft propulsion.

Adaptive Immune Response Impairs the Efficacy of Autologous Transplantation of Engineered Stem Cells in Dystrophic Dogs

Science.gov (United States)

Sitzia, Clementina; Farini, Andrea; Jardim, Luciana; Razini, Paola; Belicchi, Marzia; Cassinelli, Letizia; Villa, Chiara; Erratico, Silvia; Parolini, Daniele; Bella, Pamela; da Silva Bizario, Joao Carlos; Garcia, Luis; Dias-Baruffi, Marcelo; Meregalli, Mirella; Torrente, Yvan

2016-01-01

Duchenne muscular dystrophy is the most common genetic muscular dystrophy. It is caused by mutations in the dystrophin gene, leading to absence of muscular dystrophin and to progressive degeneration of skeletal muscle. We have demonstrated that the exon skipping method safely and efficiently brings to the expression of a functional dystrophin in dystrophic CD133+ cells injected scid/mdx mice. Golden Retriever muscular dystrophic (GRMD) dogs represent the best preclinical model of Duchenne muscular dystrophy, mimicking the human pathology in genotypic and phenotypic aspects. Here, we assess the capacity of intra-arterial delivered autologous engineered canine CD133+ cells of restoring dystrophin expression in Golden Retriever muscular dystrophy. This is the first demonstration of five-year follow up study, showing initial clinical amelioration followed by stabilization in mild and severe affected Golden Retriever muscular dystrophy dogs. The occurrence of T-cell response in three Golden Retriever muscular dystrophy dogs, consistent with a memory response boosted by the exon skipped-dystrophin protein, suggests an adaptive immune response against dystrophin. PMID:27506452

Histopathologic and immunohistochemical features of soft palate muscles and nerves in dogs with an elongated soft palate.

Science.gov (United States)

Arai, Kiyotaka; Kobayashi, Masanori; Harada, Yasuji; Hara, Yasushi; Michishita, Masaki; Ohkusu-Tsukada, Kozo; Takahashi, Kimimasa

2016-01-01

To histologically evaluate and compare features of myofibers within the elongated soft palate (ESP) of brachycephalic and mesocephalic dogs with those in the soft palate of healthy dogs and to assess whether denervation or muscular dystrophy is associated with soft palate elongation. Soft palate specimens from 24 dogs with ESPs (obtained during surgical intervention) and from 14 healthy Beagles (control group). All the soft palate specimens underwent histologic examination to assess myofiber atrophy, hypertrophy, hyalinization, and regeneration. The degrees of atrophy and hypertrophy were quantified on the basis of the coefficient of variation and the number of myofibers with hyalinization and regeneration. The specimens also underwent immunohistochemical analysis with anti-neurofilament or anti-dystrophin antibody to confirm the distribution of peripheral nerve branches innervating the palatine myofibers and myofiber dystrophin expression, respectively. Myofiber atrophy, hypertrophy, hyalinization, and regeneration were identified in almost all the ESP specimens. Degrees of atrophy and hypertrophy were significantly greater in the ESP specimens, compared with the control specimens. There were fewer palatine peripheral nerve branches in the ESP specimens than in the control specimens. Almost all the myofibers in the ESP and control specimens were dystrophin positive. These results suggested that palatine myopathy in dogs may be caused, at least in part, by denervation of the palatine muscles and not by Duchenne- or Becker-type muscular dystrophy. These soft palate changes may contribute to upper airway collapse and the progression of brachycephalic airway obstructive syndrome.

Expression of agrin, dystroglycan, and utrophin in normal renal tissue and in experimental glomerulopathies.

Science.gov (United States)

Raats, C J; van den Born, J; Bakker, M A; Oppers-Walgreen, B; Pisa, B J; Dijkman, H B; Assmann, K J; Berden, J H

2000-05-01

The dystrophin-glycoprotein complex, which comprises alpha- and beta-dystroglycan, sarcoglycans, and utrophin/dystrophin, links the cytoskeleton to agrin and laminin in the basal lamina in muscle and epithelial cells. Recently, agrin was identified as a major heparan sulfate proteoglycan in the glomerular basement membrane. In the present study, we found mRNA expression for agrin, dystroglycan, and utrophin in kidney cortex, isolated glomeruli, and cultured podocytes and mesangial cells. In immunofluorescence, agrin was found in the glomerular basement membrane. The antibodies against alpha- and beta-dystroglycan and utrophin revealed a granular podocyte-like staining pattern along the glomerular capillary wall. With immunoelectron microscopy, agrin was found in the glomerular basement membrane, dystroglycan was diffusely found over the entire cell surface of the podocytes, and utrophin was localized in the cytoplasm of the podocyte foot processes. In adriamycin nephropathy, a decrease in the glomerular capillary wall staining for dystroglycan was observed probably secondary to the extensive fusion of foot processes. Immunoelectron microscopy showed a different distribution pattern as compared to the normal kidney, with segmentally enhanced expression of dystroglycan at the basal side of the extensively fused podocyte foot processes. In passive Heymann nephritis we observed no changes in the staining intensity and distribution of the dystrophin-glycoprotein complex by immunofluorescence and immunoelectron microscopy. From these data, we conclude that agrin, dystroglycan, and utrophin are present in the glomerular capillary wall and their ultrastructural localization supports the concept that these molecules are involved in linking the podocyte cytoskeleton to the glomerular basement membrane.

Using the calculational simulating complexes when making the computer process control systems for NPP

International Nuclear Information System (INIS)

Zimakov, V.N.; Chernykh, V.P.

1998-01-01

The problems on creating calculational-simulating (CSC) and their application by developing the program and program-technical means for computer-aided process control systems at NPP are considered. The abo- ve complex is based on the all-mode real time mathematical model, functioning at a special complex of computerized means

Control of multidimensional systems on complex network

Science.gov (United States)

Bagnoli, Franco; Battistelli, Giorgio; Chisci, Luigi; Fanelli, Duccio

2017-01-01

Multidimensional systems coupled via complex networks are widespread in nature and thus frequently invoked for a large plethora of interesting applications. From ecology to physics, individual entities in mutual interactions are grouped in families, homogeneous in kind. These latter interact selectively, through a sequence of self-consistently regulated steps, whose deeply rooted architecture is stored in the assigned matrix of connections. The asymptotic equilibrium eventually attained by the system, and its associated stability, can be assessed by employing standard nonlinear dynamics tools. For many practical applications, it is however important to externally drive the system towards a desired equilibrium, which is resilient, hence stable, to external perturbations. To this end we here consider a system made up of N interacting populations which evolve according to general rate equations, bearing attributes of universality. One species is added to the pool of interacting families and used as a dynamical controller to induce novel stable equilibria. Use can be made of the root locus method to shape the needed control, in terms of intrinsic reactivity and adopted protocol of injection. The proposed method is tested on both synthetic and real data, thus enabling to demonstrate its robustness and versatility. PMID:28892493

Complexity control algorithm based on adaptive mode selection for interframe coding in high efficiency video coding

Science.gov (United States)

Chen, Gang; Yang, Bing; Zhang, Xiaoyun; Gao, Zhiyong

2017-07-01

The latest high efficiency video coding (HEVC) standard significantly increases the encoding complexity for improving its coding efficiency. Due to the limited computational capability of handheld devices, complexity constrained video coding has drawn great attention in recent years. A complexity control algorithm based on adaptive mode selection is proposed for interframe coding in HEVC. Considering the direct proportionality between encoding time and computational complexity, the computational complexity is measured in terms of encoding time. First, complexity is mapped to a target in terms of prediction modes. Then, an adaptive mode selection algorithm is proposed for the mode decision process. Specifically, the optimal mode combination scheme that is chosen through offline statistics is developed at low complexity. If the complexity budget has not been used up, an adaptive mode sorting method is employed to further improve coding efficiency. The experimental results show that the proposed algorithm achieves a very large complexity control range (as low as 10%) for the HEVC encoder while maintaining good rate-distortion performance. For the lowdelayP condition, compared with the direct resource allocation method and the state-of-the-art method, an average gain of 0.63 and 0.17 dB in BDPSNR is observed for 18 sequences when the target complexity is around 40%.

Treatment with the anti-IL-6 receptor antibody attenuates muscular dystrophy via promoting skeletal muscle regeneration in dystrophin-/utrophin-deficient mice.

Science.gov (United States)

Wada, Eiji; Tanihata, Jun; Iwamura, Akira; Takeda, Shin'ichi; Hayashi, Yukiko K; Matsuda, Ryoichi

2017-10-27

Chronic increases in the levels of the inflammatory cytokine interleukin-6 (IL-6) in serum and skeletal muscle are thought to contribute to the progression of muscular dystrophy. Dystrophin/utrophin double-knockout (dKO) mice develop a more severe and progressive muscular dystrophy than the mdx mice, the most common murine model of Duchenne muscular dystrophy (DMD). In particular, dKO mice have smaller body sizes and muscle diameters, and develop progressive kyphosis and fibrosis in skeletal and cardiac muscles. As mdx mice and DMD patients, we found that IL-6 levels in the skeletal muscle were significantly increased in dKO mice. Thus, in this study, we aimed to analyze the effects of IL-6 receptor (IL-6R) blockade on the muscle pathology of dKO mice. Male dKO mice were administered an initial injection (200 mg/kg intraperitoneally (i.p.)) of either the anti-IL-6R antibody MR16-1 or an isotype-matched control rat IgG at the age of 14 days, and were then given weekly injections (25 mg/kg i.p.) until 90 days of age. Treatment of dKO mice with the MR16-1 antibody successfully inhibited the IL-6 pathway in the skeletal muscle and resulted in a significant reduction in the expression levels of phosphorylated signal transducer and activator of transcription 3 in the skeletal muscle. Pathologically, a significant increase in the area of embryonic myosin heavy chain-positive myofibers and muscle diameter, and reduced fibrosis in the quadriceps muscle were observed. These results demonstrated the therapeutic effects of IL-6R blockade on promoting muscle regeneration. Consistently, serum creatine kinase levels were decreased. Despite these improvements observed in the limb muscles, degeneration of the diaphragm and cardiac muscles was not ameliorated by the treatment of mice with the MR16-1 antibody. As no adverse effects of treatment with the MR16-1 antibody were observed, our results indicate that the anti-IL-6R antibody is a potential therapy for muscular dystrophy

Distributed Low-Complexity Controller for Wind Power Plant in Derated Operation

DEFF Research Database (Denmark)

Biegel, Benjamin; Madjidian, Daria; Spudic, Vedrana

2013-01-01

We consider a wind power plant of megawatt wind turbines operating in derated mode. When operating in this mode, the wind power plant controller is free to distribute power set-points to the individual turbines, as long as the total power demand is met. In this work, we design a controller...... that exploits this freedom to reduce the fatigue on the turbines in the wind power plant. We show that the controller can be designed in a decentralized manner, such that each wind turbine is equipped with a local low-complexity controller relying only on few measurements and little communication. As a basis...... for the controller design, a linear wind turbine model is constructed and verified in an operational wind power plant of megawatt turbines. Due to limitations of the wind power plant available for tests, it is not possible to implement the developed controller; instead the final distributed controller is evaluated...

Impulsive Controller Design for Complex Nonlinear Singular Networked Systems with Packet Dropouts

Directory of Open Access Journals (Sweden)

Xian-Lin Zhao

2013-01-01

Full Text Available Globally exponential stability of Complex (with coupling Nonlinear Singular Impulsive Networked Control Systems (CNSINCS with packet dropouts and time-delay is investigated. Firstly, the mathematic model of CNSINCS is established. Then, by employing the method of Lyapunov functional, exponential stability criteria are obtained and the impulsive controller design method is given. Finally, some simulation results are provided to demonstrate the effectiveness of the proposed method.

Supervisory control for a complex robotic system

International Nuclear Information System (INIS)

Miller, D.J.

1988-01-01

The Robotic Radiation Survey and Analysis System investigates the use of advanced robotic technology for performing remote radiation surveys on nuclear waste shipping casks. Robotic systems have the potential for reducing personnel exposure to radiation and providing fast reliable throughput at future repository sites. A primary technology issue is the integrated control of distributed specialized hardware through a modular supervisory software system. Automated programming of robot trajectories based upon mathematical models of the cask and robot coupled with sensory feedback enables flexible operation of a commercial gantry robot with the reliability needed to perform autonomous operations in a hazardous environment. Complexity is managed using structured software engineering techniques resulting in the generation of reusable command primitives which contribute to a software parts catalog for a generalized robot programming language

Clinical and molecular consequences of exon 78 deletion in DMD gene.

Science.gov (United States)

Traverso, Monica; Assereto, Stefania; Baratto, Serena; Iacomino, Michele; Pedemonte, Marina; Diana, Maria Cristina; Ferretti, Marta; Broda, Paolo; Minetti, Carlo; Gazzerro, Elisabetta; Madia, Francesca; Bruno, Claudio; Zara, Federico; Fiorillo, Chiara

2018-03-19

We present a 13-year-old patient with persistent increase of serum Creatine Kinase (CK) and myalgia after exertion. Skeletal muscle biopsy showed marked reduction of dystrophin expression leading to genetic analysis of DMD gene by MLPA, which detected a single deletion of exon 78. To the best of our knowledge, DMD exon 78 deletion has never been described in literature and, according to prediction, it should lead to loss of reading frame in the dystrophin gene. To further assess the actual effect of exon 78 deletion, we analysed cDNA from muscle mRNA. This analysis confirmed the absence of 32 bp of exon 78. Exclusion of exon 78 changes the open reading frame of exon 79 and generate a downstream stop codon, producing a dystrophin protein of 3703 amino acids instead of 3685 amino acids. Albeit loss of reading frame usually leads to protein degradation and severe phenotype, in this case, we demonstrated that deletion of DMD exon 78 can be associated with a functional protein able to bind DGC complex and a very mild phenotype. This study adds a novel deletion in DMD gene in human and helps to define the compliance between maintaining/disrupting the reading frame and clinical form of the disease.

Coherent operation of detector systems and their readout electronics in a complex experiment control environment

Energy Technology Data Exchange (ETDEWEB)

Koestner, Stefan [CERN (Switzerland)], E-mail: koestner@mpi-halle.mpg.de

2009-09-11

With the increasing size and degree of complexity of today's experiments in high energy physics the required amount of work and complexity to integrate a complete subdetector into an experiment control system is often underestimated. We report here on the layered software structure and protocols used by the LHCb experiment to control its detectors and readout boards. The experiment control system of LHCb is based on the commercial SCADA system PVSS II. Readout boards which are outside the radiation area are accessed via embedded credit card sized PCs which are connected to a large local area network. The SPECS protocol is used for control of the front end electronics. Finite state machines are introduced to facilitate the control of a large number of electronic devices and to model the whole experiment at the level of an expert system.

Controls of multi-modal wave conditions in a complex coastal setting

Science.gov (United States)

Hegermiller, Christie; Rueda, Ana C.; Erikson, Li H.; Barnard, Patrick L.; Antolinez, J.A.A.; Mendez, Fernando J.

2017-01-01

Coastal hazards emerge from the combined effect of wave conditions and sea level anomalies associated with storms or low-frequency atmosphere-ocean oscillations. Rigorous characterization of wave climate is limited by the availability of spectral wave observations, the computational cost of dynamical simulations, and the ability to link wave-generating atmospheric patterns with coastal conditions. We present a hybrid statistical-dynamical approach to simulating nearshore wave climate in complex coastal settings, demonstrated in the Southern California Bight, where waves arriving from distant, disparate locations are refracted over complex bathymetry and shadowed by offshore islands. Contributions of wave families and large-scale atmospheric drivers to nearshore wave energy flux are analyzed. Results highlight the variability of influences controlling wave conditions along neighboring coastlines. The universal method demonstrated here can be applied to complex coastal settings worldwide, facilitating analysis of the effects of climate change on nearshore wave climate.

Design and implementation of the control system for nuclear plant VVER-1000. Instrumentation (program technical complexes)

International Nuclear Information System (INIS)

Siora, A.; Tokarev, V.; Bakhmach, E.

2004-01-01

Program-technical complexes (PTC) are designed as control and protection systems in water-moderated atomic reactors, including emergency and preventive systems, automatic control, unloading, reactor capacity limitation and accelerated preventive protection systems. Utilization of programmable logic integrated circuits from world leading manufacturers makes the complexes simple in structure, compact, with low energy demands and mutually independent for key and supporting functions The results of PTC assessment and implementation in Ukraine are outlined. Opportunities for a future development of RADIJ company in the area of control and protection systems for VVER reactors are also discussed

Distributed optimization-based control of multi-agent networks in complex environments

CERN Document Server

Zhu, Minghui

2015-01-01

This book offers a concise and in-depth exposition of specific algorithmic solutions for distributed optimization based control of multi-agent networks and their performance analysis. It synthesizes and analyzes distributed strategies for three collaborative tasks: distributed cooperative optimization, mobile sensor deployment and multi-vehicle formation control. The book integrates miscellaneous ideas and tools from dynamic systems, control theory, graph theory, optimization, game theory and Markov chains to address the particular challenges introduced by such complexities in the environment as topological dynamics, environmental uncertainties, and potential cyber-attack by human adversaries. The book is written for first- or second-year graduate students in a variety of engineering disciplines, including control, robotics, decision-making, optimization and algorithms and with backgrounds in aerospace engineering, computer science, electrical engineering, mechanical engineering and operations research. Resea...

Increased Expression of Laminin Subunit Alpha 1 Chain by dCas9-VP160

OpenAIRE

Perrin, Arnaud; Rousseau, Jo?l; Tremblay, Jacques P.

2016-01-01

Laminin-111 protein complex links the extracellular matrix to integrin α7β1 in sarcolemma, thus replacing in dystrophic muscles links normally insured by the dystrophin complex. Laminin-111 injection in mdx mouse stabilized sarcolemma, restored serum creatine kinase to wild-type levels, and protected muscles from exercised-induced damages. These results suggested that increased laminin-111 is a potential therapy for DMD. Laminin subunit beta 1 and laminin subunit gamma 1 are expressed in adul...

A design control structure for architectural firms in a highly complex and uncertain situation

NARCIS (Netherlands)

Schijlen, J.T.H.A.M.; Otter, den A.F.H.J.; Pels, H.J.

2011-01-01

A large architectural firm in a highly complex and uncertain production situation asked to improve its existing ?production control? system for design projects. To that account a research and design project of nine months at the spot was defined. The production control in the organization was based

Stoichiometry control of complex oxides by sequential pulsed-laser deposition from binary-oxide targets

Energy Technology Data Exchange (ETDEWEB)

Herklotz, A. [ORNL, Materials Science and Technology Division, Bethel Valley Road, Oak Ridge, Tennessee 37831-6056 (United States); Martin Luther University Halle-Wittenberg, Institute for Physics, Von-Danckelmann-Platz 3, 06120 Halle (Germany); Dörr, K. [Martin Luther University Halle-Wittenberg, Institute for Physics, Von-Danckelmann-Platz 3, 06120 Halle (Germany); Ward, T. Z.; Eres, G. [ORNL, Materials Science and Technology Division, Bethel Valley Road, Oak Ridge, Tennessee 37831-6056 (United States); Christen, H. M.; Biegalski, M. D. [ORNL, Center for Nanophase Materials Sciences, Bethel Valley Road, Oak Ridge, Tennessee 37831-6496 (United States)

2015-03-30

To have precise atomic layer control over interfaces, we examine the growth of complex oxides through the sequential deposition from binary targets by pulsed laser deposition. In situ reflection high-energy electron diffraction (RHEED) is used to control the growth and achieve films with excellent structural quality. The growth from binary oxide targets is fundamentally different from single target growth modes and shows more similarities to shuttered growth by molecular beam epitaxy. The RHEED intensity oscillations of non-stoichiometric growth are consistent with a model of island growth and accumulation of excess material on the surface that can be utilized to determine the correct stoichiometry for growth. Correct monolayer doses can be determined through an envelope frequency in the RHEED intensity oscillations. In order to demonstrate the ability of this growth technique to create complex heterostructures, the artificial n = 2 and 3 Sr{sub n+1}Ti{sub n}O{sub 3n+1} Ruddlesden-Popper phases are grown with good long-range order. This method enables the precise unit-cell level control over the structure of perovskite-type oxides, and thus the growth of complex materials with improved structural quality and electronic functionality.

Complex state variable- and disturbance observer-based current controllers for AC drives

DEFF Research Database (Denmark)

Dal, Mehmet; Teodorescu, Remus; Blaabjerg, Frede

2013-01-01

In vector-controlled AC drives, the design of current controller is usually based on a machine model defined in synchronous frame coordinate, where the drive performance may be degraded by both the variation of the machine parameters and the cross-coupling between the d- and q-axes components...... of the stator current. In order to improve the current control performance an alternative current control strategy was proposed previously aiming to avoid the undesired cross-coupling and non-linearities between the state variables. These effects are assumed as disturbances arisen in the closed-loop path...... of the parameter and the cross-coupling effect. Moreover, it provides a better performance, smooth and low noisy operation with respect to the complex variable controller....

IMPROVING THE EFFICIENCY OF THE STATE FINANCIAL CONTROL IN THE SPHERE OF HIGH-TECH MILITARY-INDUSTRIAL COMPLEX

Directory of Open Access Journals (Sweden)

Anzhela Zakhitovna Namitulina

2016-01-01

Full Text Available The presented research topic is particularly relevant due to the high value and the need to strengthen fi nancial control for the development of the military-industrial complex (MIC, to ensure the country's economic security, preservation and development of scientifi c and technical potential. The urgency of acquiring those aspects of economic relations which are connected with the supply the export of high-tech military products in a limited budget funding State should have levers of infl uence on the functioning of the military-industrial complex, the ability to pursue an independent foreign military-technical policy. In the new economic conditions, it became necessary to address the problems of fi nancial security of the defense-industrial complex, in order to strengthen the independence and security of Russia, as well as the need to give priority nature of the measures of state control in the economy related to the implementation of the defense order, ie, in the sphere of military-industrial complex. At the present stage of economic development of Russia, the rate of growth of the national economy largely depends on what the situation is in the military-industrial complex (MIC. This is due to the fact that the defense industry is the most high-quality, high-tech economy. It concentrated the largest part of the Russian potential, the best staff of scientists and experts. Products and DIC technology widely used in other industries. The modern military-industrial complex produces a signifi cant part of civil production. DIC integration with civilian industries – it is also a technological basis for solving the basic problems currently facing the Russian economy, and, above all, the basis of the formation of a new technological basis for the development of high technology and competitive products, which determines the pace of scientifi c and technological progress and the growth of the national economy. Objectives. The aim of the paper is the

Instructional Control of Cognitive Load in the Design of Complex Learning Environments

NARCIS (Netherlands)

Kester, Liesbeth; Paas, Fred; Van Merriënboer, Jeroen

2010-01-01

Kester, L., Paas, F., & Van Merriënboer, J. J. G. (2010). Instructional control of cognitive load in the design of complex learning environments. In J. L. Plass, R. Moreno, & Roland Brünken (Eds.), Cognitive Load Theory (pp. 109-130). New York: Cambridge University Press.

Generalized Combination Complex Synchronization for Fractional-Order Chaotic Complex Systems

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Cuimei Jiang

2015-07-01

Full Text Available Based on two fractional-order chaotic complex drive systems and one fractional-order chaotic complex response system with different dimensions, we propose generalized combination complex synchronization. In this new synchronization scheme, there are two complex scaling matrices that are non-square matrices. On the basis of the stability theory of fractional-order linear systems, we design a general controller via active control. Additionally, by virtue of two complex scaling matrices, generalized combination complex synchronization between fractional-order chaotic complex systems and real systems is investigated. Finally, three typical examples are given to demonstrate the effectiveness and feasibility of the schemes.

Control in Complex Organizations

DEFF Research Database (Denmark)

Rennstam, Jens; Kärreman, Dan

The extant research on organizational control builds on the assumption of vertical control – managers are thought to develop orders, rules and norms to control the operating core. Yet it is claimed that work becomes increasingly “knowledge intensive” and that organizations rely heavily for their ......The extant research on organizational control builds on the assumption of vertical control – managers are thought to develop orders, rules and norms to control the operating core. Yet it is claimed that work becomes increasingly “knowledge intensive” and that organizations rely heavily...... for their productivity on the knowledge and creativity of their work force. In this type of “knowledge work,” the strong focus on vertical control is insufficient as it fails to account for the important operative and horizontal interactions upon which many contemporary organizations depend. Drawing on practice theory...... and an ethnographic study of engineering work, this paper theorizes control as a form of work that does not only belong to formal management, but is dispersed among various work activities, including horizontal ones. The article introduces the idea of control work as a key practice in contemporary organizations...

Dystromirs as serum biomarkers for monitoring the disease severity in Duchenne muscular Dystrophy.

Directory of Open Access Journals (Sweden)

Irina T Zaharieva

Full Text Available Duchenne muscular Dystrophy (DMD is an inherited disease caused by mutations in the dystrophin gene that disrupt the open reading frame, while in frame mutations result in Becker muscular dystrophy (BMD. Ullrich congenital muscular dystrophy (UCMD is due to mutations affecting collagen VI genes. Specific muscle miRNAs (dystromirs are potential non-invasive biomarkers for monitoring the outcome of therapeutic interventions and disease progression. We quantified miR-1, miR-133a,b, miR-206 and miR-31 in serum from patients with DMD, BMD, UCMD and healthy controls. MiR-1, miR-133a,b and miR-206 were upregulated in DMD, but unchanged in UCMD compared to controls. Milder DMD patients had higher levels of dystromirs than more severely affected patients. Patients with low forced vital capacity (FVC values, indicating respiratory muscle weakness, had low levels of serum miR-1 and miR-133b. There was no significant difference in the level of the dystromirs in BMD compared to controls. We also assessed the effect of dystrophin restoration on the expression of the five dystromirs in serum of DMD patients treated systemically for 12 weeks with antisense oligomer eteplirsen that induces skipping of exon 51 in the dystrophin gene. The dystromirs were also analysed in muscle biopsies of DMD patients included in a single dose intramuscular eteplirsen clinical trial. Our analysis detected a trend towards normalization of these miRNA between the pre- and post-treatment samples of the systemic trial, which however failed to reach statistical significance. This could possibly be due to the small number of patients and the short duration of these clinical trials. Although longer term studies are needed to clarify the relationship between dystrophin restoration following therapeutic intervention and the level of circulating miRNAs, our results indicate that miR-1 and miR-133 can be considered as exploratory biomarkers for monitoring the progression of muscle weakness

The chondrogenic response to exercise in the proximal femur of normal and mdx mice

Directory of Open Access Journals (Sweden)

Nye David J

2010-09-01

Full Text Available Abstract Background Submaximal exercise is used in the management of muscular dystrophy. The effects of mechanical stimulation on skeletal development are well understood, although its effects on cartilage growth have yet to be investigated in the dystrophic condition. The objective of this study was to investigate the chondrogenic response to voluntary exercise in dystrophin-deficient mice. Methods Control and dystrophin-deficient (mdx mice were divided into sedentary and exercise-treated groups and tested for chondral histomorphometric differences at the proximal femur. Results Control mice ran 7 km/week further than mdx mice on average, but this difference was not statistically significant (P > 0.05. However, exercised control mice exhibited significantly enlarged femur head diameter, articular cartilage thickness, articular cartilage tissue area, and area of calcified cartilage relative to sedentary controls and exercised mdx mice (P Conclusions Mdx mice exhibit a reduced chondrogenic response to increased mechanical stimulation relative to controls. However, no significant reduction in articular dimensions was found, indicating loss of chondral tissue may not be a clinical concern with dystrophinopathy.

Emerging genetic therapies to treat Duchenne muscular dystrophy

Science.gov (United States)

Nelson, Stanley F.; Crosbie, Rachelle H.; Miceli, M. Carrie; Spencer, Melissa J.

2010-01-01

Purpose of review Duchenne muscular dystrophy is a progressive muscle degenerative disease caused by dystrophin mutations. The purpose of this review is to highlight two emerging therapies designed to repair the primary genetic defect, called `exon skipping' and `nonsense codon suppression'. Recent findings A drug, PTC124, was identified that suppresses nonsense codon translation termination. PTC124 can lead to restoration of some dystrophin expression in human Duchenne muscular dystrophy muscles with mutations resulting in premature stops. Two drugs developed for exon skipping, PRO051 and AVI-4658, result in the exclusion of exon 51 from mature mRNA. They can restore the translational reading frame to dystrophin transcripts from patients with a particular subset of dystrophin gene deletions and lead to some restoration of dystrophin expression in affected boys' muscle in vivo. Both approaches have concluded phase I trials with no serious adverse events. Summary These novel therapies that act to correct the primary genetic defect of dystrophin deficiency are among the first generation of therapies tailored to correct specific mutations in humans. Thus, they represent paradigm forming approaches to personalized medicine with the potential to lead to life changing treatment for those affected by Duchenne muscular dystrophy. PMID:19745732

Differential requirement for utrophin in the induced pluripotent stem cell correction of muscle versus fat in muscular dystrophy mice.

Directory of Open Access Journals (Sweden)

Amanda J Beck

Full Text Available Duchenne muscular dystrophy (DMD is an incurable degenerative muscle disorder. We injected WT mouse induced pluripotent stem cells (iPSCs into mdx and mdx∶utrophin mutant blastocysts, which are predisposed to develop DMD with an increasing degree of severity (mdx <<< mdx∶utrophin. In mdx chimeras, iPSC-dystrophin was supplied to the muscle sarcolemma to effect corrections at morphological and functional levels. Dystrobrevin was observed in dystrophin-positive and, at a lesser extent, utrophin-positive areas. In the mdx∶utrophin mutant chimeras, although iPSC-dystrophin was also supplied to the muscle sarcolemma, mice still displayed poor skeletal muscle histopathology, and negligible levels of dystrobrevin in dystrophin- and utrophin-negative areas. Not only dystrophin-expressing tissues are affected by iPSCs. Mdx and mdx∶utrophin mice have reduced fat/body weight ratio, but iPSC injection normalized this parameter in both mdx and mdx∶utrophin chimeras, despite the fact that utrophin was compromised in the mdx∶utrophin chimeric fat. The results suggest that the presence of utrophin is required for the iPSC-corrections in skeletal muscle. Furthermore, the results highlight a potential (utrophin-independent non-cell autonomous role for iPSC-dystrophin in the corrections of non-muscle tissue like fat, which is intimately related to the muscle.

The disruptive effects of pain on complex cognitive performance and executive control.

Directory of Open Access Journals (Sweden)

Edmund Keogh

Full Text Available Pain interferes and disrupts attention. What is less clear is how pain affects performance on complex tasks, and the strategies used to ensure optimal outcomes. The aim of the current study was to examine the effect of pain on higher-order executive control processes involved in managing complex tasks. Sixty-two adult volunteers (40 female completed two computer-based tasks: a breakfast making task and a word generation puzzle. Both were complex, involving executive control functions, including goal-directed planning and switching. Half of those recruited performed the tasks under conditions of thermal heat pain, and half with no accompanying pain. Whilst pain did not affect central performance on either task, it did have indirect effects. For the breakfast task, pain resulted in a decreased ability to multitask, with performance decrements found on the secondary task. However, no effects of pain were found on the processes thought to underpin this task. For the word generation puzzle, pain did not affect task performance, but did alter subjective accounts of the processes used to complete the task; pain affected the perceived allocation of time to the task, as well as switching perceptions. Sex differences were also found. When studying higher-order cognitive processes, pain-related interference effects are varied, and may result in subtle or indirect changes in cognition.

The disruptive effects of pain on complex cognitive performance and executive control.

Science.gov (United States)

Keogh, Edmund; Moore, David J; Duggan, Geoffrey B; Payne, Stephen J; Eccleston, Christopher

2013-01-01

Pain interferes and disrupts attention. What is less clear is how pain affects performance on complex tasks, and the strategies used to ensure optimal outcomes. The aim of the current study was to examine the effect of pain on higher-order executive control processes involved in managing complex tasks. Sixty-two adult volunteers (40 female) completed two computer-based tasks: a breakfast making task and a word generation puzzle. Both were complex, involving executive control functions, including goal-directed planning and switching. Half of those recruited performed the tasks under conditions of thermal heat pain, and half with no accompanying pain. Whilst pain did not affect central performance on either task, it did have indirect effects. For the breakfast task, pain resulted in a decreased ability to multitask, with performance decrements found on the secondary task. However, no effects of pain were found on the processes thought to underpin this task. For the word generation puzzle, pain did not affect task performance, but did alter subjective accounts of the processes used to complete the task; pain affected the perceived allocation of time to the task, as well as switching perceptions. Sex differences were also found. When studying higher-order cognitive processes, pain-related interference effects are varied, and may result in subtle or indirect changes in cognition.

Chaos synchronization and chaotization of complex chaotic systems in series form by optimal control

International Nuclear Information System (INIS)

Ge Zhengming; Yang, C.-H.

2009-01-01

By the method of quadratic optimum control, a quadratic optimal regulator is used for synchronizing two complex chaotic systems in series form. By this method the least error with less control energy is achieved, and the optimization on both energy and error is realized synthetically. The simulation results of two Quantum-CNN chaos systems in series form prove the effectiveness of this method. Finally, chaotization of the system is given by optimal control.

MODELING OF OPERATION MODES OF SHIP POWER PLANT OF COMBINED PROPULSION COMPLEX WITH CONTROL SYSTEM BASED ON ELECTRONIC CONTROLLERS

Directory of Open Access Journals (Sweden)

E. A. Yushkov

2016-12-01

Full Text Available Purpose. Designing of diagrams to optimize mathematic model of the ship power plant (SPP combined propulsion complexes (CPC for decreasing operational loss and increasing fuel efficiency with simultaneous load limiting on medium revolutions diesel generator (MRDG by criterion reducing of wear and increasing operation time between repairs. Methodology. After analyzing of ship power plant modes of CPC proposed diagrams to optimize mathematic model of the above mentioned complex. The model based on using of electronic controllers in automatic regulation and control systems for diesel and thruster which allow to actualize more complicated control algorithm with viewpoint of increasing working efficiency of ship power plant at normal and emergency modes. Results. Determined suitability of comparative computer modeling in MatLab Simulink for building of imitation model objects based on it block diagrams and mathematic descriptions. Actualized diagrams to optimize mathematic model of the ship’s power plant (SPP combined propulsion complexes (CPC with Azipod system in MatLab Simulink software package Ships_CPC for decreasing operational loss and increasing fuel efficiency with simultaneous load limiting on medium revolutions diesel generator (MRDG by criterion reducing of wear and increasing operation time between repairs. The function blocks of proposed complex are the main structural units which allow to investigate it normal and emergency modes. Originality. This model represents a set of functional blocks of the components SPP CPC, built on the principle of «input-output». For example, the function boxes outputs of PID-regulators of MRDG depends from set excitation voltage and rotating frequency that in turn depends from power-station load and respond that is a ship moving or dynamically positioning, and come on input (inputs of thruster rotating frequency PID-regulator models. Practical value. The results of researches planned to use in

An Overview of Recent Therapeutics Advances for Duchenne Muscular Dystrophy.

Science.gov (United States)

Mah, Jean K

2018-01-01

Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy in childhood. Mutations of the DMD gene destabilize the dystrophin associated glycoprotein complex in the sarcolemma. Ongoing mechanical stress leads to unregulated influx of calcium ions into the sarcoplasm, with activation of proteases, release of proinflammatory cytokines, and mitochondrial dysfunction. Cumulative damage and reparative failure leads to progressive muscle necrosis, fibrosis, and fatty replacement. Although there is presently no cure for DMD, scientific advances have led to many potential disease-modifying treatments, including dystrophin replacement therapies, upregulation of compensatory proteins, anti-inflammatory agents, and other cellular targets. Recently approved therapies include ataluren for stop codon read-through and eteplirsen for exon 51 skipping of eligible individuals. The purpose of this chapter is to summarize the clinical features of DMD, to describe current outcome measures used in clinical studies, and to highlight new emerging therapies for affected individuals.

Engineering a large application software project: the controls of the CERN PS accelerator complex

International Nuclear Information System (INIS)

Benincasa, G.P.; Daneels, A.; Heymans, P.; Serre, Ch.

1985-01-01

The CERN PS accelerator complex has been progressively converted to full computer controls without interrupting its full-time operation (more than 6000 hours per year with on average not more than 1% of the total down-time due to controls). The application software amounts to 120 man-years and 450'000 instructions: it compares with other large software projects, also outside the accelerator world: e.g. Skylab's ground support software. This paper outlines the application software structure which takes into account technical requirements and constraints (resulting from the complexity of the process and its operation) and economical and managerial ones. It presents the engineering and management techniques used to promote implementation, testing and commissioning within budget, manpower and time constraints and concludes with experience gained

Unique expression of cytoskeletal proteins in human soft palate muscles.

Science.gov (United States)

Shah, Farhan; Berggren, Diana; Holmlund, Thorbjörn; Levring Jäghagen, Eva; Stål, Per

2016-03-01

The human oropharyngeal muscles have a unique anatomy with diverse and intricate functions. To investigate if this specialization is also reflected in the cytoarchitecture of muscle fibers, intermediate filament proteins and the dystrophin-associated protein complex have been analyzed in two human palate muscles, musculus uvula (UV) and musculus palatopharyngeus (PP), with immunohistochenmical and morphological techniques. Human limb muscles were used as reference. The findings show that the soft palate muscle fibers have a cytoskeletal architecture that differs from the limb muscles. While all limb muscles showed immunoreaction for a panel of antibodies directed against different domains of cytoskeletal proteins desmin and dystrophin, a subpopulation of palate muscle fibers lacked or had a faint immunoreaction for desmin (UV 11.7% and PP 9.8%) and the C-terminal of the dystrophin molecule (UV 4.2% and PP 6.4%). The vast majority of these fibers expressed slow contractile protein myosin heavy chain I. Furthermore, an unusual staining pattern was also observed in these fibers for β-dystroglycan, caveolin-3 and neuronal nitric oxide synthase nNOS, which are all membrane-linking proteins associated with the dystrophin C-terminus. While the immunoreaction for nNOS was generally weak or absent, β-dystroglycan and caveolin-3 showed a stronger immunostaining. The absence or a low expression of cytoskeletal proteins otherwise considered ubiquitous and important for integration and contraction of muscle cells indicate a unique cytoarchitecture designed to meet the intricate demands of the upper airway muscles. It can be concluded that a subgroup of muscle fibers in the human soft palate appears to have special biomechanical properties, and their unique cytoarchitecture must be taken into account while assessing function and pathology in oropharyngeal muscles. © 2015 Anatomical Society.

Reaction-diffusion controlled growth of complex structures

Science.gov (United States)

Noorduin, Willem; Mahadevan, L.; Aizenberg, Joanna

2013-03-01

Understanding how the emergence of complex forms and shapes in biominerals came about is both of fundamental and practical interest. Although biomineralization processes and organization strategies to give higher order architectures have been studied extensively, synthetic approaches to mimic these self-assembled structures are highly complex and have been difficult to emulate, let alone replicate. The emergence of solution patterns has been found in reaction-diffusion systems such as Turing patterns and the BZ reaction. Intrigued by this spontaneous formation of complexity we explored if similar processes can lead to patterns in the solid state. We here identify a reaction-diffusion system in which the shape of the solidified products is a direct readout of the environmental conditions. Based on insights in the underlying mechanism, we developed a toolbox of engineering strategies to deterministically sculpt patterns and shapes, and combine different morphologies to create a landscape of hierarchical multi scale-complex tectonic architectures with unprecedented levels of complexity. These findings may hold profound implications for understanding, mimicking and ultimately expanding upon nature's morphogenesis strategies, allowing the synthesis of advanced highly complex microscale materials and devices. WLN acknowledges the Netherlands Organization for Scientific Research for financial support

Backbone of complex networks of corporations: The flow of control

Science.gov (United States)

Glattfelder, J. B.; Battiston, S.

2009-09-01

We present a methodology to extract the backbone of complex networks based on the weight and direction of links, as well as on nontopological properties of nodes. We show how the methodology can be applied in general to networks in which mass or energy is flowing along the links. In particular, the procedure enables us to address important questions in economics, namely, how control and wealth are structured and concentrated across national markets. We report on the first cross-country investigation of ownership networks, focusing on the stock markets of 48 countries around the world. On the one hand, our analysis confirms results expected on the basis of the literature on corporate control, namely, that in Anglo-Saxon countries control tends to be dispersed among numerous shareholders. On the other hand, it also reveals that in the same countries, control is found to be highly concentrated at the global level, namely, lying in the hands of very few important shareholders. Interestingly, the exact opposite is observed for European countries. These results have previously not been reported as they are not observable without the kind of network analysis developed here.

Analysis and Control of Epidemics: A survey of spreading processes on complex networks

OpenAIRE

Nowzari, Cameron; Preciado, Victor M.; Pappas, George J.

2015-01-01

This article reviews and presents various solved and open problems in the development, analysis, and control of epidemic models. We are interested in presenting a relatively concise report for new engineers looking to enter the field of spreading processes on complex networks.

Complex motion of a vehicle through a series of signals controlled by power-law phase

Science.gov (United States)

Nagatani, Takashi

2017-07-01

We study the dynamic motion of a vehicle moving through the series of traffic signals controlled by the position-dependent phase of power law. All signals are controlled by both cycle time and position-dependent phase. The dynamic model of the vehicular motion is described in terms of the nonlinear map. The vehicular motion varies in a complex manner by varying cycle time for various values of the power of the position-dependent phase. The vehicle displays the periodic motion with a long cycle for the integer power of the phase, while the vehicular motion exhibits the very complex behavior for the non-integer power of the phase.

Trade-offs between driving nodes and time-to-control in complex networks

Science.gov (United States)

Pequito, Sérgio; Preciado, Victor M.; Barabási, Albert-László; Pappas, George J.

2017-01-01

Recent advances in control theory provide us with efficient tools to determine the minimum number of driving (or driven) nodes to steer a complex network towards a desired state. Furthermore, we often need to do it within a given time window, so it is of practical importance to understand the trade-offs between the minimum number of driving/driven nodes and the minimum time required to reach a desired state. Therefore, we introduce the notion of actuation spectrum to capture such trade-offs, which we used to find that in many complex networks only a small fraction of driving (or driven) nodes is required to steer the network to a desired state within a relatively small time window. Furthermore, our empirical studies reveal that, even though synthetic network models are designed to present structural properties similar to those observed in real networks, their actuation spectra can be dramatically different. Thus, it supports the need to develop new synthetic network models able to replicate controllability properties of real-world networks.

Synchronization of coupled stochastic complex-valued dynamical networks with time-varying delays via aperiodically intermittent adaptive control

Science.gov (United States)

Wang, Pengfei; Jin, Wei; Su, Huan

2018-04-01

This paper deals with the synchronization problem of a class of coupled stochastic complex-valued drive-response networks with time-varying delays via aperiodically intermittent adaptive control. Different from the previous works, the intermittent control is aperiodic and adaptive, and the restrictions on the control width and time delay are removed, which lead to a larger application scope for this control strategy. Then, based on the Lyapunov method and Kirchhoff's Matrix Tree Theorem as well as differential inequality techniques, several novel synchronization conditions are derived for the considered model. Specially, impulsive control is also considered, which can be seen as a special case of the aperiodically intermittent control when the control width tends to zero. And the corresponding synchronization criteria are given as well. As an application of the theoretical results, a class of stochastic complex-valued coupled oscillators with time-varying delays is studied, and the numerical simulations are also given to demonstrate the effectiveness of the control strategies.

Investigating the Complexity of Transitioning Separation Assurance Tools into NextGen Air Traffic Control

Science.gov (United States)

Gomez, Ashley Nicole; Martin, Lynne Hazel; Homola, Jeffrey; Morey, Susan; Cabrall, Christopher; Mercer, Joey; Prevot, Thomas

2013-01-01

In a study, that introduced ground-based separation assurance automation through a series of envisioned transitional phases of concept maturity, it was found that subjective responses to scales of workload, situation awareness, and acceptability in a post run questionnaire revealed as-predicted results for three of the four study conditions but not for the third, Moderate condition. The trend continued for losses of separation (LOS) where the number of LOS events were far greater than expected in the Moderate condition. To offer an account of why the Moderate condition was perceived to be more difficult to manage than predicted, researchers examined the increase in amount and complexity of traffic, increase in communication load, and increased complexities as a result of the simulation's mix of aircraft equipage. Further analysis compared the tools presented through the phases, finding that controllers took advantage of the informational properties of the tools presented but shied away from using their decision support capabilities. Taking into account similar findings from other studies, it is suggested that the Moderate condition represented the first step into a "shared control" environment, which requires the controller to use the automation as a decision making partner rather than just a provider of information. Viewed in this light, the combination of tools offered in the Moderate condition was reviewed and some tradeoffs that may offset the identified complexities were suggested.

Assisted reproductive techniques and risk of exstrophy-epispadias complex: a German case-control study.

Science.gov (United States)

Zwink, Nadine; Jenetzky, Ekkehart; Hirsch, Karin; Reifferscheid, Peter; Schmiedeke, Eberhard; Schmidt, Dominik; Reckin, Sabrina; Obermayr, Florian; Boemers, Thomas M; Stein, Raimund; Reutter, Heiko; Rösch, Wolfgang H; Brenner, Hermann; Ebert, Anne-Karoline

2013-04-01

We assessed the risk of exstrophy-epispadias complex in children conceived by in vitro fertilization or intracytoplasmic sperm injection. Data from the German Network for Congenital Uro-REctal malformations were compared to nationwide data from the German In Vitro Fertilization Register and the German Federal Statistical Office. Odds ratios (95% CI) were determined to quantify associations using logistic regression. A total of 123 patients with exstrophy-epispadias complex born in Germany between 1997 and 2011 were recruited through participating departments of pediatric urology and pediatric surgery throughout the country as well as the German self-help organizations Blasenekstrophie/Epispadie e.V. and Kloakenekstrophie. All German live births (10,069,986) between 1997 and 2010 comprised the controls. Overall, 12 subjects (10%) and 129,982 controls (1%) were conceived by in vitro fertilization or intracytoplasmic sperm injection. Conception by assisted reproductive technique was associated with a more than eightfold increased risk of exstrophy-epispadias complex compared to spontaneous conception (OR 8.3, 95% CI 4.6-15.0, p risk of exstrophy-epispadias complex in children conceived by in vitro fertilization (OR 14.0, 95% CI 6.5-30.0, p study provides evidence that assisted reproductive techniques such as in vitro fertilization and intracytoplasmic sperm injection are associated with a markedly increased risk of having a child born with exstrophy-epispadias complex. However, it remains unclear whether this finding may be due to assisted reproduction per se and/or underlying infertility/subfertility etiology or parent characteristics. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Quantum control with noisy fields: computational complexity versus sensitivity to noise

International Nuclear Information System (INIS)

Kallush, S; Khasin, M; Kosloff, R

2014-01-01

A closed quantum system is defined as completely controllable if an arbitrary unitary transformation can be executed using the available controls. In practice, control fields are a source of unavoidable noise, which has to be suppressed to retain controllability. Can one design control fields such that the effect of noise is negligible on the time-scale of the transformation? This question is intimately related to the fundamental problem of a connection between the computational complexity of the control problem and the sensitivity of the controlled system to noise. The present study considers a paradigm of control, where the Lie-algebraic structure of the control Hamiltonian is fixed, while the size of the system increases with the dimension of the Hilbert space representation of the algebra. We find two types of control tasks, easy and hard. Easy tasks are characterized by a small variance of the evolving state with respect to the operators of the control operators. They are relatively immune to noise and the control field is easy to find. Hard tasks have a large variance, are sensitive to noise and the control field is hard to find. The influence of noise increases with the size of the system, which is measured by the scaling factor N of the largest weight of the representation. For fixed time and control field the ability to control degrades as O(N) for easy tasks and as O(N 2 ) for hard tasks. As a consequence, even in the most favorable estimate, for large quantum systems, generic noise in the controls dominates for a typical class of target transformations, i.e. complete controllability is destroyed by noise. (paper)

Power systems control complex optimization in the new market conditions

International Nuclear Information System (INIS)

Krumm, L.; Kurrel, U.; Tauts, A.; Terno, O.; Zeidmanis, I.; Krisans, Z.

2000-01-01

A generalization and development of the theory and methods for complex optimisation of the performance and development control of an interconnected system (IPS) under new market conditions (mainly multicriterial and game approaches) is given considering the specifics of IPS at the international level in post-socialist countries and in particular in the Baltic states. Thereby the kernel of the mathematical apparatus of this theory the Generalized Reduced Gradient Method (GRGM) is further generalised and developed with the application of multicriterial and game methods to meet various market conditions. (author)

Pinning-controlled synchronization of complex networks with bounded or unbounded synchronized regions

International Nuclear Information System (INIS)

Yan-Li, Zou; Guan-Rong, Chen

2009-01-01

This paper studies pinning-controlled synchronization of complex networks with bounded or unbounded synchronized regions. To study a state-feedback pinning-controlled network with N nodes, it first converts the controlled network to an extended network of N+1 nodes without controls. It is shown that the controlled synchronizability of the given network is determined by the real part of the smallest nonzero eigenvalue of the coupling matrix of its extended network when the synchronized region is unbounded; but it is determined by the ratio of the real parts of the largest and the smallest nonzero eigenvalues of the coupling matrix when the synchronized region is bounded. Both theoretical analysis and numerical simulation show that the portion of controlled nodes has no critical values when the synchronized region is unbounded, but it has a critical value when the synchronized region is bounded. In the former case, therefore, it is possible to control the network to achieve synchronization by pinning only one node. In the latter case, the network can achieve controlled synchronization only when the portion of controlled nodes is larger than the critical value. (general)

Becker muscular dystrophy-like myopathy regarded as so-called "fatty muscular dystrophy" in a pig: a case report and its diagnostic method.

Science.gov (United States)

Horiuchi, Noriyuki; Aihara, Naoyuki; Mizutani, Hiroshi; Kousaka, Shinichi; Nagafuchi, Tsuneyuki; Ochiai, Mariko; Ochiai, Kazuhiko; Kobayashi, Yoshiyasu; Furuoka, Hidefumi; Asai, Tetsuo; Oishi, Koji

2014-03-01

We describe a case of human Becker muscular dystrophy (BMD)-like myopathy that was characterized by the declined stainability of dystrophin at sarcolemma in a pig and the immunostaining for dystrophin on the formalin-fixed, paraffin-embedded (FFPE) tissue. The present case was found in a meat inspection center. The pig looked appeared healthy at the ante-mortem inspection. Muscular abnormalities were detected after carcass dressing as pale, discolored skeletal muscles with prominent fat infiltrations and considered so-called "fatty muscular dystrophy". Microscopic examination revealed following characteristics: diffused fat infiltration into the skeletal muscle and degeneration and regeneration of the remaining skeletal muscle fibers. Any lesions that were suspected of neurogenic atrophy, traumatic muscular degeneration, glycogen storage disease or other porcine muscular disorders were not observed. The immunostaining for dystrophin was conducted and confirmed to be applicable on FFPE porcine muscular tissues and revealed diminished stainability of dystrophin at the sarcolemma in the present case. Based on the histological observations and immunostaining results, the present case was diagnosed with BMD-like myopathy associated with dystrophin abnormality in a pig. Although the genetic properties were not clear, the present BMD-like myopathy implied the occurrence of dystrophinopathy in pigs. To the best of our knowledge, this is the first report of a natural case of myopathy associated with dystrophin abnormalities in a pig.

Contribution of oxidative stress to pathology in diaphragm and limb muscles with Duchenne muscular dystrophy.

Science.gov (United States)

Kim, Jong-Hee; Kwak, Hyo-Bum; Thompson, LaDora V; Lawler, John M

2013-02-01

Duchenne muscular dystrophy (DMD) is a degenerative skeletal muscle disease that makes walking and breathing difficult. DMD is caused by an X-linked (Xp21) mutation in the dystrophin gene. Dystrophin is a scaffolding protein located in the sarcolemmal cytoskeleton, important in maintaining structural integrity and regulating muscle cell (muscle fiber) growth and repair. Dystrophin deficiency in mouse models (e.g., mdx mouse) destabilizes the interface between muscle fibers and the extracellular matrix, resulting in profound damage, inflammation, and weakness in diaphragm and limb muscles. While the link between dystrophin deficiency with inflammation and pathology is multi-factorial, elevated oxidative stress has been proposed as a central mediator. Unfortunately, the use of non-specific antioxidant scavengers in mouse and human studies has led to inconsistent results, obscuring our understanding of the importance of redox signaling in pathology of muscular dystrophy. However, recent studies with more mechanistic approaches in mdx mice suggest that NAD(P)H oxidase and nuclear factor-kappaB are important in amplifying dystrophin-deficient muscle pathology. Therefore, more targeted antioxidant therapeutics may ameliorate damage and weakness in human population, thus promoting better muscle function and quality of life. This review will focus upon the pathobiology of dystrophin deficiency in diaphragm and limb muscle primarily in mouse models, with a rationale for development of targeted therapeutic antioxidants in DMD patients.

In vivo myomaker-mediated heterologous fusion and nuclear reprogramming.

Science.gov (United States)

Mitani, Yasuyuki; Vagnozzi, Ronald J; Millay, Douglas P

2017-01-01

Knowledge regarding cellular fusion and nuclear reprogramming may aid in cell therapy strategies for skeletal muscle diseases. An issue with cell therapy approaches to restore dystrophin expression in muscular dystrophy is obtaining a sufficient quantity of cells that normally fuse with muscle. Here we conferred fusogenic activity without transdifferentiation to multiple non-muscle cell types and tested dystrophin restoration in mouse models of muscular dystrophy. We previously demonstrated that myomaker, a skeletal muscle-specific transmembrane protein necessary for myoblast fusion, is sufficient to fuse 10T 1/2 fibroblasts to myoblasts in vitro. Whether myomaker-mediated heterologous fusion is functional in vivo and whether the newly introduced nonmuscle nuclei undergoes nuclear reprogramming has not been investigated. We showed that mesenchymal stromal cells, cortical bone stem cells, and tail-tip fibroblasts fuse to skeletal muscle when they express myomaker. These cells restored dystrophin expression in a fraction of dystrophin-deficient myotubes after fusion in vitro. However, dystrophin restoration was not detected in vivo although nuclear reprogramming of the muscle-specific myosin light chain promoter did occur. Despite the lack of detectable dystrophin reprogramming by immunostaining, this study indicated that myomaker could be used in nonmuscle cells to induce fusion with muscle in vivo, thereby providing a platform to deliver therapeutic material.-Mitani, Y., Vagnozzi, R. J., Millay, D. P. In vivo myomaker-mediated heterologous fusion and nuclear reprogramming. © FASEB.

Metformin selectively targets redox control of complex I energy transduction

Directory of Open Access Journals (Sweden)

Amy R. Cameron

2018-04-01

Full Text Available Many guanide-containing drugs are antihyperglycaemic but most exhibit toxicity, to the extent that only the biguanide metformin has enjoyed sustained clinical use. Here, we have isolated unique mitochondrial redox control properties of metformin that are likely to account for this difference. In primary hepatocytes and H4IIE hepatoma cells we found that antihyperglycaemic diguanides DG5-DG10 and the biguanide phenformin were up to 1000-fold more potent than metformin on cell signalling responses, gluconeogenic promoter expression and hepatocyte glucose production. Each drug inhibited cellular oxygen consumption similarly but there were marked differences in other respects. All diguanides and phenformin but not metformin inhibited NADH oxidation in submitochondrial particles, indicative of complex I inhibition, which also corresponded closely with dehydrogenase activity in living cells measured by WST-1. Consistent with these findings, in isolated mitochondria, DG8 but not metformin caused the NADH/NAD+ couple to become more reduced over time and mitochondrial deterioration ensued, suggesting direct inhibition of complex I and mitochondrial toxicity of DG8. In contrast, metformin exerted a selective oxidation of the mitochondrial NADH/NAD+ couple, without triggering mitochondrial deterioration. Together, our results suggest that metformin suppresses energy transduction by selectively inducing a state in complex I where redox and proton transfer domains are no longer efficiently coupled. Keywords: Diabetes, Metformin, Mitochondria, NADH, NAD+

Complex dynamics and bifurcation analysis of host–parasitoid models with impulsive control strategy

International Nuclear Information System (INIS)

Yang, Jin; Tang, Sanyi; Tan, Yuanshun

2016-01-01

Highlights: • We develop novel host-parasitoid models with impulsive control strategy. • The effects of key parameters on the successful control have been addressed. • The complex dynamics and related biological significance are investigated. • The results between two types of host-parasitoid models have been discussed. - Abstract: In this paper, we propose and analyse two type host–parasitoid models with integrated pest management (IPM) interventions as impulsive control strategies. For fixed pulsed model, the threshold condition for the global stability of the host-eradication periodic solution is provided, and the effects of key parameters including the impulsive period, proportionate killing rate, instantaneous search rate, releasing constant, survival rate and the proportionate release rate on the threshold condition are discussed. Then latin hypercube sampling /partial rank correlation coefficients are used to carry out sensitivity analyses to determine the significance of each parameters. Further, bifurcation analyses are presented and the results show that coexistence of attractors existed for a wide range of parameters, and the switch-like transitions among these attractors indicate that varying dosages and frequencies of insecticide applications and numbers of parasitoid released are crucial for IPM strategy. For unfixed pulsed model, the results show that this model exists very complex dynamics and the host population can be controlled below ET, and it implies that the modelling methods are helpful for improving optimal strategies to design appropriate IPM.

Source pollution control program at the Camacari Petrochemical Complex: overall and individual improvements

Energy Technology Data Exchange (ETDEWEB)

Freire, P A; Neto, D B; Carvalho, D M [CETREL S.A., Camacari, BA (Brazil)

1994-12-31

Along with the technical progress experienced by the Camacari Petrochemical Complex in the last few years, new policies, following new worldwide trends, in pollution control and prevention became mandatory. This work describes some of these experiences as well as future perspectives. 3 refs., 2 fig., 13 tabs.

Source pollution control program at the Camacari Petrochemical Complex: overall and individual improvements

Energy Technology Data Exchange (ETDEWEB)

Freire, P.A.; Neto, D.B.; Carvalho, D.M. [CETREL S.A., Camacari, BA (Brazil)

1993-12-31

Along with the technical progress experienced by the Camacari Petrochemical Complex in the last few years, new policies, following new worldwide trends, in pollution control and prevention became mandatory. This work describes some of these experiences as well as future perspectives. 3 refs., 2 fig., 13 tabs.

Complexity Analysis of a Master-Slave Oligopoly Model and Chaos Control

Directory of Open Access Journals (Sweden)

Junhai Ma

2014-01-01

Full Text Available We establish a master-slave oligopoly game model with an upstream monopoly whose output is considered and two downstream oligopolies whose prices are considered. The existence and the local stable region of the Nash equilibrium point are investigated. The complex dynamic properties, such as bifurcation and chaos, are analyzed using bifurcation diagrams, the largest Lyapunov exponent diagrams, and the strange attractor graph. We further analyze the long-run average profit of the three firms and find that they are all optimal in the stable region. In addition, delay feedback control method and limiter control method are used in nondelayed model to control chaos. Furthermore, a delayed master-slave oligopoly game model is considered, and the three firms’ profit in various conditions is analyzed. We find that suitable delayed parameters are important for eliminating chaos and maximizing the profit of the players.

Adaptive generalized combination complex synchronization of uncertain real and complex nonlinear systems

Energy Technology Data Exchange (ETDEWEB)

Wang, Shi-bing, E-mail: wang-shibing@dlut.edu.cn, E-mail: wangxy@dlut.edu.cn [School of Computer and Information Engineering, Fuyang Normal University, Fuyang 236041 (China); Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024 (China); Wang, Xing-yuan, E-mail: wang-shibing@dlut.edu.cn, E-mail: wangxy@dlut.edu.cn [Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024 (China); Wang, Xiu-you [School of Computer and Information Engineering, Fuyang Normal University, Fuyang 236041 (China); Zhou, Yu-fei [College of Electrical Engineering and Automation, Anhui University, Hefei 230601 (China)

2016-04-15

With comprehensive consideration of generalized synchronization, combination synchronization and adaptive control, this paper investigates a novel adaptive generalized combination complex synchronization (AGCCS) scheme for different real and complex nonlinear systems with unknown parameters. On the basis of Lyapunov stability theory and adaptive control, an AGCCS controller and parameter update laws are derived to achieve synchronization and parameter identification of two real drive systems and a complex response system, as well as two complex drive systems and a real response system. Two simulation examples, namely, ACGCS for chaotic real Lorenz and Chen systems driving a hyperchaotic complex Lü system, and hyperchaotic complex Lorenz and Chen systems driving a real chaotic Lü system, are presented to verify the feasibility and effectiveness of the proposed scheme.

Adaptive control of structural balance for complex dynamical networks based on dynamic coupling of nodes

Science.gov (United States)

Gao, Zilin; Wang, Yinhe; Zhang, Lili

2018-02-01

In the existing research results of the complex dynamical networks controlled, the controllers are mainly used to guarantee the synchronization or stabilization of the nodes’ state, and the terms coupled with connection relationships may affect the behaviors of nodes, this obviously ignores the dynamic common behavior of the connection relationships between the nodes. In fact, from the point of view of large-scale system, a complex dynamical network can be regarded to be composed of two time-varying dynamic subsystems, which can be called the nodes subsystem and the connection relationships subsystem, respectively. Similar to the synchronization or stabilization of the nodes subsystem, some characteristic phenomena can be also emerged in the connection relationships subsystem. For example, the structural balance in the social networks and the synaptic facilitation in the biological neural networks. This paper focuses on the structural balance in dynamic complex networks. Generally speaking, the state of the connection relationships subsystem is difficult to be measured accurately in practical applications, and thus it is not easy to implant the controller directly into the connection relationships subsystem. It is noted that the nodes subsystem and the relationships subsystem are mutually coupled, which implies that the state of the connection relationships subsystem can be affected by the controllable state of nodes subsystem. Inspired by this observation, by using the structural balance theory of triad, the controller with the parameter adaptive law is proposed for the nodes subsystem in this paper, which may ensure the connection relationship matrix to approximate a given structural balance matrix in the sense of the uniformly ultimately bounded (UUB). That is, the structural balance may be obtained by employing the controlling state of the nodes subsystem. Finally, the simulations are used to show the validity of the method in this paper.

Heregulin ameliorates the dystrophic phenotype in mdx mice

DEFF Research Database (Denmark)

Krag, Thomas O B; Bogdanovich, Sasha; Jensen, Claus J

2004-01-01

Duchenne's muscular dystrophy (DMD) is a fatal neuromuscular disease caused by absence of dystrophin. Utrophin is a chromosome 6-encoded dystrophin-related protein (DRP), sharing functional motifs with dystrophin. Utrophin's ability to compensate for dystrophin during development and when....... Therefore, this pathway offers a potential mechanism to modulate utrophin expression in muscle. We tested the ability of heregulin to improve the dystrophic phenotype in the mdx mouse model of DMD. Intraperitoneal injections of a small peptide encoding the epidermal growth factor-like region of heregulin...... ectodomain for 3 months in vivo resulted in up-regulation of utrophin, a marked improvement in the mechanical properties of muscle as evidenced by resistance to eccentric contraction mediated damage, and a reduction of muscle pathology. The amelioration of dystrophic phenotype by heregulin-mediated utrophin...

Complex Formation Control of Large-Scale Intelligent Autonomous Vehicles

Directory of Open Access Journals (Sweden)

Ming Lei

2012-01-01

Full Text Available A new formation framework of large-scale intelligent autonomous vehicles is developed, which can realize complex formations while reducing data exchange. Using the proposed hierarchy formation method and the automatic dividing algorithm, vehicles are automatically divided into leaders and followers by exchanging information via wireless network at initial time. Then, leaders form formation geometric shape by global formation information and followers track their own virtual leaders to form line formation by local information. The formation control laws of leaders and followers are designed based on consensus algorithms. Moreover, collision-avoiding problems are considered and solved using artificial potential functions. Finally, a simulation example that consists of 25 vehicles shows the effectiveness of theory.

Predictability, Force and (Anti-)Resonance in Complex Object Control.

Science.gov (United States)

Maurice, Pauline; Hogan, Neville; Sternad, Dagmar

2018-04-18

Manipulation of complex objects as in tool use is ubiquitous and has given humans an evolutionary advantage. This study examined the strategies humans choose when manipulating an object with underactuated internal dynamics, such as a cup of coffee. The object's dynamics renders the temporal evolution complex, possibly even chaotic, and difficult to predict. A cart-and-pendulum model, loosely mimicking coffee sloshing in a cup, was implemented in a virtual environment with a haptic interface. Participants rhythmically manipulated the virtual cup containing a rolling ball; they could choose the oscillation frequency, while the amplitude was prescribed. Three hypotheses were tested: 1) humans decrease interaction forces between hand and object; 2) humans increase the predictability of the object dynamics; 3) humans exploit the resonances of the coupled object-hand system. Analysis revealed that humans chose either a high-frequency strategy with anti-phase cup-and-ball movements or a low-frequency strategy with in-phase cup-and-ball movements. Counter Hypothesis 1, they did not decrease interaction force; instead, they increased the predictability of the interaction dynamics, quantified by mutual information, supporting Hypothesis 2. To address Hypothesis 3, frequency analysis of the coupled hand-object system revealed two resonance frequencies separated by an anti-resonance frequency. The low-frequency strategy exploited one resonance, while the high-frequency strategy afforded more choice, consistent with the frequency response of the coupled system; both strategies avoided the anti-resonance. Hence, humans did not prioritize interaction force, but rather strategies that rendered interactions predictable. These findings highlight that physical interactions with complex objects pose control challenges not present in unconstrained movements.

The Control Based on Internal Average Kinetic Energy in Complex Environment for Multi-robot System

Science.gov (United States)

Yang, Mao; Tian, Yantao; Yin, Xianghua

In this paper, reference trajectory is designed according to minimum energy consumed for multi-robot system, which nonlinear programming and cubic spline interpolation are adopted. The control strategy is composed of two levels, which lower-level is simple PD control and the upper-level is based on the internal average kinetic energy for multi-robot system in the complex environment with velocity damping. Simulation tests verify the effectiveness of this control strategy.

Complexity and Pilot Workload Metrics for the Evaluation of Adaptive Flight Controls on a Full Scale Piloted Aircraft

Science.gov (United States)

Hanson, Curt; Schaefer, Jacob; Burken, John J.; Larson, David; Johnson, Marcus

2014-01-01

Flight research has shown the effectiveness of adaptive flight controls for improving aircraft safety and performance in the presence of uncertainties. The National Aeronautics and Space Administration's (NASA)'s Integrated Resilient Aircraft Control (IRAC) project designed and conducted a series of flight experiments to study the impact of variations in adaptive controller design complexity on performance and handling qualities. A novel complexity metric was devised to compare the degrees of simplicity achieved in three variations of a model reference adaptive controller (MRAC) for NASA's F-18 (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) Full-Scale Advanced Systems Testbed (Gen-2A) aircraft. The complexity measures of these controllers are also compared to that of an earlier MRAC design for NASA's Intelligent Flight Control System (IFCS) project and flown on a highly modified F-15 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois). Pilot comments during the IRAC research flights pointed to the importance of workload on handling qualities ratings for failure and damage scenarios. Modifications to existing pilot aggressiveness and duty cycle metrics are presented and applied to the IRAC controllers. Finally, while adaptive controllers may alleviate the effects of failures or damage on an aircraft's handling qualities, they also have the potential to introduce annoying changes to the flight dynamics or to the operation of aircraft systems. A nuisance rating scale is presented for the categorization of nuisance side-effects of adaptive controllers.

Models and synchronization of time-delayed complex dynamical networks with multi-links based on adaptive control

International Nuclear Information System (INIS)

Peng Haipeng; Wei Nan; Li Lixiang; Xie Weisheng; Yang Yixian

2010-01-01

In this Letter, time-delay has been introduced in to split the networks, upon which a model of complex dynamical networks with multi-links has been constructed. Moreover, based on Lyapunov stability theory and some hypotheses, we achieve synchronization between two complex networks with different structures by designing effective controllers. The validity of the results was proved through numerical simulations of this Letter.

Dual AAV therapy ameliorates exercise-induced muscle injury and functional ischemia in murine models of Duchenne muscular dystrophy.

Science.gov (United States)

Zhang, Yadong; Yue, Yongping; Li, Liang; Hakim, Chady H; Zhang, Keqing; Thomas, Gail D; Duan, Dongsheng

2013-09-15

Neuronal nitric oxide synthase (nNOS) membrane delocalization contributes to the pathogenesis of Duchenne muscular dystrophy (DMD) by promoting functional muscle ischemia and exacerbating muscle injury during exercise. We have previously shown that supra-physiological expression of nNOS-binding mini-dystrophin restores normal blood flow regulation and prevents functional ischemia in transgenic mdx mice, a DMD model. A critical next issue is whether systemic dual adeno-associated virus (AAV) gene therapy can restore nNOS-binding mini-dystrophin expression and mitigate muscle activity-related functional ischemia and injury. Here, we performed systemic gene transfer in mdx and mdx4cv mice using a pair of dual AAV vectors that expressed a 6 kb nNOS-binding mini-dystrophin gene. Vectors were packaged in tyrosine mutant AAV-9 and co-injected (5 × 10(12) viral genome particles/vector/mouse) via the tail vein to 1-month-old dystrophin-null mice. Four months later, we observed 30-50% mini-dystrophin positive myofibers in limb muscles. Treatment ameliorated histopathology, increased muscle force and protected against eccentric contraction-induced injury. Importantly, dual AAV therapy successfully prevented chronic exercise-induced muscle force drop. Doppler hemodynamic assay further showed that therapy attenuated adrenergic vasoconstriction in contracting muscle. Our results suggest that partial transduction can still ameliorate nNOS delocalization-associated functional deficiency. Further evaluation of nNOS binding mini-dystrophin dual AAV vectors is warranted in dystrophic dogs and eventually in human patients.

Neurocognitive Profiles in Duchenne Muscular Dystrophy and Gene Mutation Site

Science.gov (United States)

D’Angelo, Maria Grazia; Lorusso, Maria Luisa; Civati, Federica; Comi, Giacomo Pietro; Magri, Francesca; Del Bo, Roberto; Guglieri, Michela; Molteni, Massimo; Turconi, Anna Carla; Bresolin, Nereo

2011-01-01

The presence of nonprogressive cognitive impairment is recognized as a common feature in a substantial proportion of patients with Duchenne muscular dystrophy. To investigate the possible role of mutations along the dystrophin gene affecting different brain dystrophin isoforms and specific cognitive profiles, 42 school-age children affected with Duchenne muscular dystrophy, subdivided according to sites of mutations along the dystrophin gene, underwent a battery of tests tapping a wide range of intellectual, linguistic, and neuropsychologic functions. Full-scale intelligence quotient was approximately 1 S.D. below the population average in the whole group of dystrophic children. Patients with Duchenne muscular dystrophy and mutations located in the distal portion of the dystrophin gene (involving the 140-kDa brain protein isoform, called Dp140) were generally more severely affected and expressed different patterns of strengths and impairments, compared with patients with Duchenne muscular dystrophy and mutations located in the proximal portion of the dystrophin gene (not involving Dp140). Patients with Duchenne muscular dystrophy and distal mutations demonstrated specific impairments in visuospatial functions and visual memory (which seemed intact in proximally mutated patients) and greater impairment in syntactic processing. PMID:22000308

Interactions between default mode and control networks as a function of increasing cognitive reasoning complexity.

Science.gov (United States)

Hearne, Luke; Cocchi, Luca; Zalesky, Andrew; Mattingley, Jason B

2015-07-01

Successful performance of challenging cognitive tasks depends on a consistent functional segregation of activity within the default-mode network, on the one hand, and control networks encompassing frontoparietal and cingulo-opercular areas on the other. Recent work, however, has suggested that in some cognitive control contexts nodes within the default-mode and control networks may actually cooperate to achieve optimal task performance. Here, we used functional magnetic resonance imaging to examine whether the ability to relate variables while solving a cognitive reasoning problem involves transient increases in connectivity between default-mode and control regions. Participants performed a modified version of the classic Wason selection task, in which the number of variables to be related is systematically varied across trials. As expected, areas within the default-mode network showed a parametric deactivation with increases in relational complexity, compared with neural activity in null trials. Critically, some of these areas also showed enhanced connectivity with task-positive control regions. Specifically, task-based connectivity between the striatum and the angular gyri, and between the thalamus and right temporal pole, increased as a function of relational complexity. These findings challenge the notion that functional segregation between regions within default-mode and control networks invariably support cognitive task performance, and reveal previously unknown roles for the striatum and thalamus in managing network dynamics during cognitive reasoning. © 2015 Wiley Periodicals, Inc.

Complexity Management - A multiple case study analysis on control and reduction of complexity costs

DEFF Research Database (Denmark)

Myrodia, Anna

of products, with features more custom-made to cover individual needs, both regarding characteristics of products and support services. This necessity leads to a considerable increase of the complexity in the company, which affects the product portfolio, production and supply chain, market segments......, IT systems, and business processes. In order to identify and eliminate complexity, several approaches are used, both by researchers and practitioners. The purpose of this thesis is to contribute to the existing knowledge of complexity management theory. This research focuses on the relationship between......Complexity tends to be arguably the biggest challenge of manufacturing companies. The motivation of further studying complexity is a combination between the existing literature and the practical experiences from the industry. Based on the latest trend companies are trying to supply a growing mix...

Master-slave exponential synchronization of delayed complex-valued memristor-based neural networks via impulsive control.

Science.gov (United States)

Li, Xiaofan; Fang, Jian-An; Li, Huiyuan

2017-09-01

This paper investigates master-slave exponential synchronization for a class of complex-valued memristor-based neural networks with time-varying delays via discontinuous impulsive control. Firstly, the master and slave complex-valued memristor-based neural networks with time-varying delays are translated to two real-valued memristor-based neural networks. Secondly, an impulsive control law is constructed and utilized to guarantee master-slave exponential synchronization of the neural networks. Thirdly, the master-slave synchronization problems are transformed into the stability problems of the master-slave error system. By employing linear matrix inequality (LMI) technique and constructing an appropriate Lyapunov-Krasovskii functional, some sufficient synchronization criteria are derived. Finally, a numerical simulation is provided to illustrate the effectiveness of the obtained theoretical results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Controlled molecular self-assembly of complex three-dimensional structures in soft materials.

Science.gov (United States)

Huang, Changjin; Quinn, David; Suresh, Subra; Hsia, K Jimmy

2018-01-02

Many applications in tissue engineering, flexible electronics, and soft robotics call for approaches that are capable of producing complex 3D architectures in soft materials. Here we present a method using molecular self-assembly to generate hydrogel-based 3D architectures that resembles the appealing features of the bottom-up process in morphogenesis of living tissues. Our strategy effectively utilizes the three essential components dictating living tissue morphogenesis to produce complex 3D architectures: modulation of local chemistry, material transport, and mechanics, which can be engineered by controlling the local distribution of polymerization inhibitor (i.e., oxygen), diffusion of monomers/cross-linkers through the porous structures of cross-linked polymer network, and mechanical constraints, respectively. We show that oxygen plays a role in hydrogel polymerization which is mechanistically similar to the role of growth factors in tissue growth, and the continued growth of hydrogel enabled by diffusion of monomers/cross-linkers into the porous hydrogel similar to the mechanisms of tissue growth enabled by material transport. The capability and versatility of our strategy are demonstrated through biomimetics of tissue morphogenesis for both plants and animals, and its application to generate other complex 3D architectures. Our technique opens avenues to studying many growth phenomena found in nature and generating complex 3D structures to benefit diverse applications. Copyright © 2017 the Author(s). Published by PNAS.

Optical angular constancy is maintained as a navigational control strategy when pursuing robots moving along complex pathways.

Science.gov (United States)

Wang, Wei; McBeath, Michael K; Sugar, Thomas G

2015-03-24

The optical navigational control strategy used to intercept moving targets was explored using a real-world object that travels along complex, evasive pathways. Fielders ran across a gymnasium attempting to catch a moving robot that varied in speed and direction, while ongoing position was measured using an infrared motion-capture system. Fielder running paths were compared with the predictions of three lateral control models, each based on maintaining a particular optical angle relative to the robotic target: (a) constant alignment angle (CAA), (b) constant eccentricity angle (CEA), and (c) linear optical trajectory (LOT). Findings reveal that running pathways were most consistent with maintenance of LOT and least consistent with CEA. This supports that fielders use the same optical control strategy of maintaining angular constancy using a LOT when navigating toward targets moving along complex pathways as when intercepting simple ballistic trajectories. In those cases in which a target dramatically deviates from its optical path, fielders appear to simply reset LOT parameters using a new constant angle value. Maintenance of such optical angular constancy has now been shown to work well with ballistic, complex, and evasive moving targets, confirming the LOT strategy as a robust, general-purpose optical control mechanism for navigating to intercept catchable targets, both airborne and ground based. © 2015 ARVO.

Sarcospan Regulates Cardiac Isoproterenol Response and Prevents Duchenne Muscular Dystrophy-Associated Cardiomyopathy.

Science.gov (United States)

Parvatiyar, Michelle S; Marshall, Jamie L; Nguyen, Reginald T; Jordan, Maria C; Richardson, Vanitra A; Roos, Kenneth P; Crosbie-Watson, Rachelle H

2015-12-23

Duchenne muscular dystrophy is a fatal cardiac and skeletal muscle disease resulting from mutations in the dystrophin gene. We have previously demonstrated that a dystrophin-associated protein, sarcospan (SSPN), ameliorated Duchenne muscular dystrophy skeletal muscle degeneration by activating compensatory pathways that regulate muscle cell adhesion (laminin-binding) to the extracellular matrix. Conversely, loss of SSPN destabilized skeletal muscle adhesion, hampered muscle regeneration, and reduced force properties. Given the importance of SSPN to skeletal muscle, we investigated the consequences of SSPN ablation in cardiac muscle and determined whether overexpression of SSPN into mdx mice ameliorates cardiac disease symptoms associated with Duchenne muscular dystrophy cardiomyopathy. SSPN-null mice exhibited cardiac enlargement, exacerbated cardiomyocyte hypertrophy, and increased fibrosis in response to β-adrenergic challenge (isoproterenol; 0.8 mg/day per 2 weeks). Biochemical analysis of SSPN-null cardiac muscle revealed reduced sarcolemma localization of many proteins with a known role in cardiomyopathy pathogenesis: dystrophin, the sarcoglycans (α-, δ-, and γ-subunits), and β1D integrin. Transgenic overexpression of SSPN in Duchenne muscular dystrophy mice (mdx(TG)) improved cardiomyofiber cell adhesion, sarcolemma integrity, cardiac functional parameters, as well as increased expression of compensatory transmembrane proteins that mediate attachment to the extracellular matrix. SSPN regulates sarcolemmal expression of laminin-binding complexes that are critical to cardiac muscle function and protects against transient and chronic injury, including inherited cardiomyopathy. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Verification and Validation Challenges for Adaptive Flight Control of Complex Autonomous Systems

Science.gov (United States)

Nguyen, Nhan T.

2018-01-01

Autonomy of aerospace systems requires the ability for flight control systems to be able to adapt to complex uncertain dynamic environment. In spite of the five decades of research in adaptive control, the fact still remains that currently no adaptive control system has ever been deployed on any safety-critical or human-rated production systems such as passenger transport aircraft. The problem lies in the difficulty with the certification of adaptive control systems since existing certification methods cannot readily be used for nonlinear adaptive control systems. Research to address the notion of metrics for adaptive control began to appear in the recent years. These metrics, if accepted, could pave a path towards certification that would potentially lead to the adoption of adaptive control as a future control technology for safety-critical and human-rated production systems. Development of certifiable adaptive control systems represents a major challenge to overcome. Adaptive control systems with learning algorithms will never become part of the future unless it can be proven that they are highly safe and reliable. Rigorous methods for adaptive control software verification and validation must therefore be developed to ensure that adaptive control system software failures will not occur, to verify that the adaptive control system functions as required, to eliminate unintended functionality, and to demonstrate that certification requirements imposed by regulatory bodies such as the Federal Aviation Administration (FAA) can be satisfied. This presentation will discuss some of the technical issues with adaptive flight control and related V&V challenges.

Code Samples Used for Complexity and Control

Science.gov (United States)

Ivancevic, Vladimir G.; Reid, Darryn J.

2015-11-01

The following sections are included: * MathematicaⓇ Code * Generic Chaotic Simulator * Vector Differential Operators * NLS Explorer * 2C++ Code * C++ Lambda Functions for Real Calculus * Accelerometer Data Processor * Simple Predictor-Corrector Integrator * Solving the BVP with the Shooting Method * Linear Hyperbolic PDE Solver * Linear Elliptic PDE Solver * Method of Lines for a Set of the NLS Equations * C# Code * Iterative Equation Solver * Simulated Annealing: A Function Minimum * Simple Nonlinear Dynamics * Nonlinear Pendulum Simulator * Lagrangian Dynamics Simulator * Complex-Valued Crowd Attractor Dynamics * Freeform Fortran Code * Lorenz Attractor Simulator * Complex Lorenz Attractor * Simple SGE Soliton * Complex Signal Presentation * Gaussian Wave Packet * Hermitian Matrices * Euclidean L2-Norm * Vector/Matrix Operations * Plain C-Code: Levenberg-Marquardt Optimizer * Free Basic Code: 2D Crowd Dynamics with 3000 Agents

A Model of Human Decision Making in Complex Systems and its Use for Design of System Control Strategies

DEFF Research Database (Denmark)

Rasmussen, Jens; Lind, Morten

The paper describes a model of operators' decision making in complex system control, based on studies of event reports and performance in control rooms. This study shows how operators base their decisions on knowledge of system properties at different levels of abstraction depending on their perc...... representation of system properties in a multilevel flow model is described to provide a basis for an integrated control system design.......The paper describes a model of operators' decision making in complex system control, based on studies of event reports and performance in control rooms. This study shows how operators base their decisions on knowledge of system properties at different levels of abstraction depending...... on their perception of the system's immediate control requirements. These levels correspond to the abstraction hierarchy including system purpose, functions, and physical details, which is generally used to describe a formal design process. In emergency situations the task of the operator is to design a suitable...

Nonlinear Decoupling Control With ANFIS-Based Unmodeled Dynamics Compensation for a Class of Complex Industrial Processes.

Science.gov (United States)

Zhang, Yajun; Chai, Tianyou; Wang, Hong; Wang, Dianhui; Chen, Xinkai

2018-06-01

Complex industrial processes are multivariable and generally exhibit strong coupling among their control loops with heavy nonlinear nature. These make it very difficult to obtain an accurate model. As a result, the conventional and data-driven control methods are difficult to apply. Using a twin-tank level control system as an example, a novel multivariable decoupling control algorithm with adaptive neural-fuzzy inference system (ANFIS)-based unmodeled dynamics (UD) compensation is proposed in this paper for a class of complex industrial processes. At first, a nonlinear multivariable decoupling controller with UD compensation is introduced. Different from the existing methods, the decomposition estimation algorithm using ANFIS is employed to estimate the UD, and the desired estimating and decoupling control effects are achieved. Second, the proposed method does not require the complicated switching mechanism which has been commonly used in the literature. This significantly simplifies the obtained decoupling algorithm and its realization. Third, based on some new lemmas and theorems, the conditions on the stability and convergence of the closed-loop system are analyzed to show the uniform boundedness of all the variables. This is then followed by the summary on experimental tests on a heavily coupled nonlinear twin-tank system that demonstrates the effectiveness and the practicability of the proposed method.

Brain Function in Duchenne Muscular Dystrophy

Directory of Open Access Journals (Sweden)

J. Gordon Millichap

2002-02-01

Full Text Available The role of dystrophin disorders in the CNS function of boys with Duchenne muscular dystrophy (DMD and the dystrophin-deficient mdx mouse, an animal model of DMD, is reviewed at the University of New South Wales, University of Sydney, Australia.

Duchenne and Becker Muscular Dystrophy: Contribution of a Molecular and Immunohistochemical Analysis in Diagnosis in Morocco

Directory of Open Access Journals (Sweden)

Hanane Bellayou

2009-01-01

Full Text Available Duchenne muscular dystrophy (DMD and Becker muscular dystrophy (BMD are X-linked recessive disorders caused by mutations of the DMD gene located at Xp21. In DMD patients, dystrophin is virtually absent; whereas BMD patients have 10% to 40% of the normal amount. Deletions in the dystrophin gene represent 65% of mutations in DMD/BMD patients. To explain the contribution of immunohistochemical and genetic analysis in the diagnosis of these dystrophies, we present 10 cases of DMD/BMD with particular features. We have analyzed the patients with immunohistochemical staining and PCR multiplex to screen for exons deletions. Determination of the quantity and distribution of dystrophin by immunohistochemical staining can confirm the presence of dystrophinopathy and allows differentiation between DMD and BMD, but dystrophin staining is not always conclusive in BMD. Therefore, only identification involved mutation by genetic analysis can establish a correct diagnosis.

Effective algorithm for solving complex problems of production control and of material flows control of industrial enterprise

Science.gov (United States)

Mezentsev, Yu A.; Baranova, N. V.

2018-05-01

A universal economical and mathematical model designed for determination of optimal strategies for managing subsystems (components of subsystems) of production and logistics of enterprises is considered. Declared universality allows taking into account on the system level both production components, including limitations on the ways of converting raw materials and components into sold goods, as well as resource and logical restrictions on input and output material flows. The presented model and generated control problems are developed within the framework of the unified approach that allows one to implement logical conditions of any complexity and to define corresponding formal optimization tasks. Conceptual meaning of used criteria and limitations are explained. The belonging of the generated tasks of the mixed programming with the class of NP is shown. An approximate polynomial algorithm for solving the posed optimization tasks for mixed programming of real dimension with high computational complexity is proposed. Results of testing the algorithm on the tasks in a wide range of dimensions are presented.

CONTROLLING AS A MECHANISM TO INCREASE THE EFFICIENCY OF MANAGEMENT ENTERPRISES OF FUEL-ENERGY COMPLEX

Directory of Open Access Journals (Sweden)

M. A. Ostashkin

2013-01-01

Full Text Available This article discusses the possibility of application of controlling as mechanism of increasing the efficiency of management of enterprises of fuel- energy complex. The research was conducted on the materials of the JSC «Gazprom».

What qualitative research can contribute to a randomized controlled trial of a complex community intervention.

Science.gov (United States)

Nelson, Geoffrey; Macnaughton, Eric; Goering, Paula

2015-11-01

Using the case of a large-scale, multi-site Canadian Housing First research demonstration project for homeless people with mental illness, At Home/Chez Soi, we illustrate the value of qualitative methods in a randomized controlled trial (RCT) of a complex community intervention. We argue that quantitative RCT research can neither capture the complexity nor tell the full story of a complex community intervention. We conceptualize complex community interventions as having multiple phases and dimensions that require both RCT and qualitative research components. Rather than assume that qualitative research and RCTs are incommensurate, a more pragmatic mixed methods approach was used, which included using both qualitative and quantitative methods to understand program implementation and outcomes. At the same time, qualitative research was used to examine aspects of the intervention that could not be understood through the RCT, such as its conception, planning, sustainability, and policy impacts. Through this example, we show how qualitative research can tell a more complete story about complex community interventions. Copyright © 2015 Elsevier Inc. All rights reserved.

Optimal Design of Complex Passive-Damping Systems for Vibration Control of Large Structures: An Energy-to-Peak Approach

Directory of Open Access Journals (Sweden)

Francisco Palacios-Quiñonero

2014-01-01

Full Text Available We present a new design strategy that makes it possible to synthesize decentralized output-feedback controllers by solving two successive optimization problems with linear matrix inequality (LMI constraints. In the initial LMI optimization problem, two auxiliary elements are computed: a standard state-feedback controller, which can be taken as a reference in the performance assessment, and a matrix that facilitates a proper definition of the main LMI optimization problem. Next, by solving the second optimization problem, the output-feedback controller is obtained. The proposed strategy extends recent results in static output-feedback control and can be applied to design complex passive-damping systems for vibrational control of large structures. More precisely, by taking advantages of the existing link between fully decentralized velocity-feedback controllers and passive linear dampers, advanced active feedback control strategies can be used to design complex passive-damping systems, which combine the simplicity and robustness of passive control systems with the efficiency of active feedback control. To demonstrate the effectiveness of the proposed approach, a passive-damping system for the seismic protection of a five-story building is designed with excellent results.

The Duchenne brain

NARCIS (Netherlands)

Doorenweerd, N.

2017-01-01

Duchenne muscular dystrophy (DMD) is characterized by progressive muscle weakness caused by DMD gene mutations leading to absence of the full-length dystrophin protein in muscle. Multiple dystrophin isoforms are expressed in brain, but little is known about their function. DMD is associated with

Antisense mediated exon skipping therapy for duchenne muscular dystrophy (DMD)

DEFF Research Database (Denmark)

Brolin, Camilla; Shiraishi, Takehiko

2011-01-01

Duchenne Muscular Dystrophy (DMD) is a lethal disease caused by mutations in the dystrophin gene (DMD) that result in the absence of essential muscle protein dystrophin. Among many different approaches for DMD treatment, exon skipping, mediated by antisense oligonucleotides, is one of the most...

Complex Dynamical Network Control for Trajectory Tracking Using Delayed Recurrent Neural Networks

Directory of Open Access Journals (Sweden)

Jose P. Perez

2014-01-01

Full Text Available In this paper, the problem of trajectory tracking is studied. Based on the V-stability and Lyapunov theory, a control law that achieves the global asymptotic stability of the tracking error between a delayed recurrent neural network and a complex dynamical network is obtained. To illustrate the analytic results, we present a tracking simulation of a dynamical network with each node being just one Lorenz’s dynamical system and three identical Chen’s dynamical systems.

Synchronization in node of complex networks consist of complex chaotic system

Energy Technology Data Exchange (ETDEWEB)

Wei, Qiang, E-mail: qiangweibeihua@163.com [Beihua University computer and technology College, BeiHua University, Jilin, 132021, Jilin (China); Digital Images Processing Institute of Beihua University, BeiHua University, Jilin, 132011, Jilin (China); Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, 116024 (China); Xie, Cheng-jun [Beihua University computer and technology College, BeiHua University, Jilin, 132021, Jilin (China); Digital Images Processing Institute of Beihua University, BeiHua University, Jilin, 132011, Jilin (China); Liu, Hong-jun [School of Information Engineering, Weifang Vocational College, Weifang, 261041 (China); Li, Yan-hui [The Library, Weifang Vocational College, Weifang, 261041 (China)

2014-07-15

A new synchronization method is investigated for node of complex networks consists of complex chaotic system. When complex networks realize synchronization, different component of complex state variable synchronize up to different scaling complex function by a designed complex feedback controller. This paper change synchronization scaling function from real field to complex field for synchronization in node of complex networks with complex chaotic system. Synchronization in constant delay and time-varying coupling delay complex networks are investigated, respectively. Numerical simulations are provided to show the effectiveness of the proposed method.

A novel instrumented multipeg running wheel system, Step-Wheel, for monitoring and controlling complex sequential stepping in mice.

Science.gov (United States)

Kitsukawa, Takashi; Nagata, Masatoshi; Yanagihara, Dai; Tomioka, Ryohei; Utsumi, Hideko; Kubota, Yasuo; Yagi, Takeshi; Graybiel, Ann M; Yamamori, Tetsuo

2011-07-01

Motor control is critical in daily life as well as in artistic and athletic performance and thus is the subject of intense interest in neuroscience. Mouse models of movement disorders have proven valuable for many aspects of investigation, but adequate methods for analyzing complex motor control in mouse models have not been fully established. Here, we report the development of a novel running-wheel system that can be used to evoke simple and complex stepping patterns in mice. The stepping patterns are controlled by spatially organized pegs, which serve as footholds that can be arranged in adjustable, ladder-like configurations. The mice run as they drink water from a spout, providing reward, while the wheel turns at a constant speed. The stepping patterns of the mice can thus be controlled not only spatially, but also temporally. A voltage sensor to detect paw touches is attached to each peg, allowing precise registration of footfalls. We show that this device can be used to analyze patterns of complex motor coordination in mice. We further demonstrate that it is possible to measure patterns of neural activity with chronically implanted tetrodes as the mice engage in vigorous running bouts. We suggest that this instrumented multipeg running wheel (which we name the Step-Wheel System) can serve as an important tool in analyzing motor control and motor learning in mice.

Dynamic complexities in a pest control model with birth pulse and harvesting

International Nuclear Information System (INIS)

Goel, A.; Gakkhar, S.

2016-01-01

In this paper, an impulsive model is discussed for an integrated pest management approach comprising of chemical and mechanical controls. The pesticides and harvesting are used to control the stage-structured pest population. The mature pest give birth to immature pest in pulses at regular intervals. The pest is controlled by spraying chemical pesticides affecting immature as well as mature pest. The harvesting of both immature and mature pest further reduce the pest population. The discrete dynamical system obtained from stroboscopic map is analyzed. The threshold conditions for stability of pest-free state as well as non-trivial period-1 solution is obtained. The effect of pesticide spray timing and harvesting on immature as well as mature pest are shown. Finally, by numerical simulation with MATLAB, the dynamical behaviors of the model is found to be complex. Above the threshold level there is a characteristic sequence of bifurcations leading to chaotic dynamics. Route to chaos is found to be period-doubling. Period halving bifurcations are also observed.

Dynamic complexities in a pest control model with birth pulse and harvesting

Energy Technology Data Exchange (ETDEWEB)

Goel, A., E-mail: goelanju23@gmail.com; Gakkhar, S., E-mail: sungkfma@iitr.ernet.in [Department of Mathematics, Indian Institute of Technology, Roorkee, Uttarakhand 247667 (India)

2016-04-06

In this paper, an impulsive model is discussed for an integrated pest management approach comprising of chemical and mechanical controls. The pesticides and harvesting are used to control the stage-structured pest population. The mature pest give birth to immature pest in pulses at regular intervals. The pest is controlled by spraying chemical pesticides affecting immature as well as mature pest. The harvesting of both immature and mature pest further reduce the pest population. The discrete dynamical system obtained from stroboscopic map is analyzed. The threshold conditions for stability of pest-free state as well as non-trivial period-1 solution is obtained. The effect of pesticide spray timing and harvesting on immature as well as mature pest are shown. Finally, by numerical simulation with MATLAB, the dynamical behaviors of the model is found to be complex. Above the threshold level there is a characteristic sequence of bifurcations leading to chaotic dynamics. Route to chaos is found to be period-doubling. Period halving bifurcations are also observed.

Control protocol: large scale implementation at the CERN PS complex - a first assessment

International Nuclear Information System (INIS)

Abie, H.; Benincasa, G.; Coudert, G.; Davydenko, Y.; Dehavay, C.; Gavaggio, R.; Gelato, G.; Heinze, W.; Legras, M.; Lustig, H.; Merard, L.; Pearson, T.; Strubin, P.; Tedesco, J.

1994-01-01

The Control Protocol is a model-based, uniform access procedure from a control system to accelerator equipment. It was proposed at CERN about 5 years ago and prototypes were developed in the following years. More recently, this procedure has been finalized and implemented at a large scale in the PS Complex. More than 300 pieces of equipment are now using this protocol in normal operation and another 300 are under implementation. These include power converters, vacuum systems, beam instrumentation devices, RF equipment, etc. This paper describes how the single general procedure is applied to the different kinds of equipment. The advantages obtained are also discussed. ((orig.))

Clinical characterisation of Becker muscular dystrophy patients predicts favourable outcome in exon-skipping therapy

NARCIS (Netherlands)

van den Bergen, J. C.; Schade van Westrum, S. M.; Dekker, L.; van der Kooi, A. J.; de Visser, M.; Wokke, B. H. A.; Straathof, C. S.; Hulsker, M. A.; Aartsma-Rus, A.; Verschuuren, J. J.; Ginjaar, H. B.

2014-01-01

Objective Duchenne and Becker muscular dystrophy (DMD/BMD) are both caused by mutations in the DMD gene. Out-of-frame mutations in DMD lead to absence of the dystrophin protein, while in-frame BMD mutations cause production of internally deleted dystrophin. Clinically, patients with DMD loose

PITX2 Enhances the Regenerative Potential of Dystrophic Skeletal Muscle Stem Cells.

Science.gov (United States)

Vallejo, Daniel; Hernández-Torres, Francisco; Lozano-Velasco, Estefanía; Rodriguez-Outeiriño, Lara; Carvajal, Alejandra; Creus, Carlota; Franco, Diego; Aránega, Amelia Eva

2018-04-10

Duchenne muscular dystrophy (DMD), one of the most lethal genetic disorders, involves progressive muscle degeneration resulting from the absence of DYSTROPHIN. Lack of DYSTROPHIN expression in DMD has critical consequences in muscle satellite stem cells including a reduced capacity to generate myogenic precursors. Here, we demonstrate that the c-isoform of PITX2 transcription factor modifies the myogenic potential of dystrophic-deficient satellite cells. We further show that PITX2c enhances the regenerative capability of mouse DYSTROPHIN-deficient satellite cells by increasing cell proliferation and the number of myogenic committed cells, but importantly also increasing dystrophin-positive (revertant) myofibers by regulating miR-31. These PITX2-mediated effects finally lead to improved muscle function in dystrophic (DMD/mdx) mice. Our studies reveal a critical role for PITX2 in skeletal muscle repair and may help to develop therapeutic strategies for muscular disorders. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Dimensional Control and Morphological Transformations of Supramolecular Polymeric Nanofibers Based on Cofacially-Stacked Planar Amphiphilic Platinum(II) Complexes.

Science.gov (United States)

Robinson, Matthew E; Nazemi, Ali; Lunn, David J; Hayward, Dominic W; Boott, Charlotte E; Hsiao, Ming-Siao; Harniman, Robert L; Davis, Sean A; Whittell, George R; Richardson, Robert M; De Cola, Luisa; Manners, Ian

2017-09-26

Square-planar platinum(II) complexes often stack cofacially to yield supramolecular fiber-like structures with interesting photophysical properties. However, control over fiber dimensions and the resulting colloidal stability is limited. We report the self-assembly of amphiphilic Pt(II) complexes with solubilizing ancillary ligands based on polyethylene glycol [PEG n , where n = 16, 12, 7]. The complex with the longest solubilizing PEG ligand, Pt-PEG 16 , self-assembled to form polydisperse one-dimensional (1D) nanofibers (diameters fibers of length up to ca. 400 nm. The fiber lengths were dependent on the Pt-PEG 16 complex to seed mass ratio in a manner analogous to a living covalent polymerization of molecular monomers. Moreover, the fiber lengths were unchanged in solution after 1 week and were therefore "static" with respect to interfiber exchange processes on this time scale. In contrast, similarly formed near-uniform fibers of Pt-PEG 12 exhibited dynamic behavior that led to broadening of the length distribution within 48 h. After aging for 4 weeks in solution, Pt-PEG 12 fibers partially evolved into 2D platelets. Furthermore, self-assembly of Pt-PEG 7 yielded only transient fibers which rapidly evolved into 2D platelets. On addition of further fiber-forming Pt complex (Pt-PEG 16 ), the platelets formed assemblies via the growth of fibers selectively from their short edges. Our studies demonstrate that when interfiber dynamic exchange is suppressed, dimensional control and hierarchical structure formation are possible for supramolecular polymers through the use of kinetically controlled seeded growth methods.

INTERPOLYELECTROLYTE COMPLEXES AS PROSPECTIVE CARRIERS FOR CONTROLLED DRUG DELIVERY

OpenAIRE

Kaur Jasmeet; Harikumar S.L.; Kaur Amanpreet

2012-01-01

In the current scenario, polymers as carriers have revolutionized the drug delivery system. A more successful approach, to exploit the different properties of polymers in a solitary system is the complexation of polymers to form polyelectrolyte complexes. These complexes circumvent the use of chemical crosslinking agents, thereby reducing the risk of toxicity. The complex formed is generally applied in different dosage forms for the formulation of stable aggregated macromolecules. There are t...

Effect of the Postural Challenge on the Dependence of the Cardiovascular Control Complexity on Age

Directory of Open Access Journals (Sweden)

Aparecida M. Catai

2014-12-01

Full Text Available Short-term complexity of heart period (HP and systolic arterial pressure (SAP was computed to detect age and gender influences over cardiovascular control in resting supine condition (REST and during standing (STAND. Healthy subjects (n = 110, men = 55 were equally divided into five groups (21–30; 31–40; 41–50; 51–60; and 61–70 years of age. HP and SAP series were recorded for 15 min at REST and during STAND. A normalized complexity index (NCI based on conditional entropy was assessed. At REST we found that both NCIHP and NCISAP decreased with age in the overall population, but only women were responsible for this trend. During STAND we observed that both NCIHP and NCISAP were unrelated to age in the overall population, even when divided by gender. When the variation of NCI in response to STAND (ΔNCI = NCI at REST-NCI during STAND was computed individually, we found that ΔNCIHP progressively decreased with age in the overall population, and women were again responsible for this trend. Conversely, ΔNCISAP was unrelated to age and gender. This study stresses that the complexity of cardiovascular control and its ability to respond to stressors are more importantly lost with age in women than in men.

Reservoir-based Online Adaptive Forward Models with Neural Control for Complex Locomotion in a Hexapod Robot

DEFF Research Database (Denmark)

Manoonpong, Poramate; Dasgupta, Sakyasingha; Goldschmidt, Dennis

2014-01-01

Walking animals show fascinating locomotor abilities and complex behaviors. Biological study has revealed that such complex behaviors is a result of a combination of biomechanics and neural mechanisms. While biomechanics allows for flexibility and a variety of movements, neural mechanisms generate...... locomotion, make predictions, and provide adaptation. Inspired by this finding, we present here an artificial bio-inspired walking system which combines biomechanics (in terms of its body and leg structures) and neural mechanisms. The neural mechanisms consist of 1) central pattern generator-based control...... for generating basic rhythmic patterns and coordinated movements, 2) reservoir-based adaptive forward models with efference copies for sensory prediction as well as state estimation, and 3) searching and elevation control for adapting the movement of an individual leg to deal with different environmental...

Control of Future Air Traffic Systems via Complexity Bound Management

Science.gov (United States)

Alexandrov, Natalia

2013-01-01

The complexity of the present system for managing air traffic has led to "discreteness" in approaches to creating new concepts: new concepts are created as point designs, based on experience, expertise, and creativity of the proposer. Discrete point designs may be highly successful but they are difficult to substantiate in the face of equally strong substantiation of competing concepts, as well as the state of the art in concept evaluation via simulations. Hybrid concepts may present a compromise - the golden middle. Yet a hybrid of sometimes in principle incompatible concepts forms another point design that faces the challenge of substantiation and validation. We are faced with the need to re-design the air transportation system ab initio. This is a daunting task, especially considering the problem of transitioning from the present system to any fundamentally new system. However, design from scratch is also an opportunity to reconsider approaches to new concept development. In this position paper we propose an approach, Optimized Parametric Functional Design, for systematic development of concepts for management and control of airspace systems, based on optimization formulations in terms of required system functions and states. This reasoning framework, realizable in the context of ab initio system design, offers an approach to deriving substantiated airspace management and control concepts. With growing computational power, we hope that the approach will also yield a methodology for actual dynamic control of airspace

Epigenetic Regulators Modulate Muscle Damage in Duchenne Muscular Dystrophy Model.

Science.gov (United States)

Bajanca, Fernanda; Vandel, Laurence

2017-12-21

Histone acetyl transferases (HATs) and histone deacetylases (HDAC) control transcription during myogenesis. HDACs promote chromatin condensation, inhibiting gene transcription in muscle progenitor cells until myoblast differentiation is triggered and HDACs are released. HATs, namely CBP/p300, activate myogenic regulatory and elongation factors promoting myogenesis. HDAC inhibitors are known to improve regeneration in dystrophic muscles through follistatin upregulation. However, the potential of directly modulating HATs remains unexplored. We tested this possibility in a well-known zebrafish model of Duchenne muscular dystrophy. Interestingly, CBP/p300 transcripts were found downregulated in the absence of Dystrophin. While investigating CBP rescuing potential we observed that dystrophin-null embryos overexpressing CBP actually never show significant muscle damage, even before a first regeneration cycle could occur. We found that the pan-HDAC inhibitor trichostatin A (TSA) also prevents early muscle damage, however the single HAT CBP is as efficient even in low doses. The HAT domain of CBP is required for its full rescuing ability. Importantly, both CBP and TSA prevent early muscle damage without restoring endogenous CBP/p300 neither increasing follistatin transcripts. This suggests a new mechanism of action of epigenetic regulators protecting dystrophin-null muscle fibres from detaching, independent from the known improvement of regeneration upon damage of HDACs inhibitors. This study builds supporting evidence that epigenetic modulators may play a role in determining the severity of muscle dystrophy, controlling the ability to resist muscle damage. Determining the mode of action leading to muscle protection can potentially lead to new treatment options for muscular dystrophies in the future.

Outer synchronization of complex networks with internal delay and coupling delay via aperiodically intermittent pinning control

Science.gov (United States)

Zhang, Chuan; Wang, Xingyuan; Wang, Chunpeng; Xia, Zhiqiu

This paper concerns the outer synchronization problem between two complex delayed networks via the method of aperiodically intermittent pinning control. Apart from previous works, internal delay and coupling delay are both involved in this model, and the designed intermittent controllers can be aperiodic. The main work in this paper can be summarized as follows: First, two cases of aperiodically intermittent control with constant gain and adaptive gain are implemented, respectively. The intermittent control and pinning control are combined to reduce consumptions further. Then, based on the Lyapunov stability theory, synchronization protocols are given by strict derivation. Especially, the designed controllers are indeed simple and valid in application of theory to practice. Finally, numerical examples put the proposed control methods to the test.

Controlled synthesis of titania using water-soluble titanium complexes: A review

Science.gov (United States)

Truong, Quang Duc; Dien, Luong Xuan; Vo, Dai-Viet N.; Le, Thanh Son

2017-07-01

The development of human society has led to the increase in energy and resources consumption as well as the arising problems of environmental damage and the toxicity to the human health. The development of novel synthesis method which tolerates utilization of toxic solvents and chemicals would fulfill the demand of the society for safer, softer, and environmental friendly technologies. For the past decades, a remarkable progress has been attained in the development of new water-soluble titanium complexes (WSTC) and their use for the synthesis of nanocrystalline titanium dioxide materials by aqueous solution-based approaches. The progress of synthesis of nanocrystalline titanium dioxide using such WSTCs is reviewed in this work. The key structural features responsible for the successfully controlled synthesis of TiO2 are discussed to provide guidelines for the morphology-controlled synthesis. Finally, this review ends with a summary and some perspectives on the challenges as well as new directions in this fascinating research.

Integrated circuit devices in control systems of coal mining complexes

Energy Technology Data Exchange (ETDEWEB)

1983-01-01

Systems of automatic monitoring and control of coal mining complexes developed in the 1960's used electromagnetic relays, thyristors, and flip-flops on transistors of varying conductivity. The circuits' designers, devoted much attention to ensuring spark safety, lowering power consumption, and raising noise immunity and repairability of functional devices. The fast development of integrated circuitry led to the use of microelectronic components in most devices of mine automation. An analysis of specifications and experimental research into integrated circuits (IMS) shows that the series K 176 IMS components made by CMOS technology best meet mine conditions of operation. The use of IMS devices under mine conditions has demonstrated their high reliability. Further development of integrated circuitry involve using microprocessors and microcomputers. (SC)

Tadalafil alleviates muscle ischemia in patients with Becker muscular dystrophy.

Science.gov (United States)

Martin, Elizabeth A; Barresi, Rita; Byrne, Barry J; Tsimerinov, Evgeny I; Scott, Bryan L; Walker, Ashley E; Gurudevan, Swaminatha V; Anene, Francine; Elashoff, Robert M; Thomas, Gail D; Victor, Ronald G

2012-11-28

Becker muscular dystrophy (BMD) is a progressive X-linked muscle wasting disease for which there is no treatment. Like Duchenne muscular dystrophy (DMD), BMD is caused by mutations in the gene encoding dystrophin, a structural cytoskeletal protein that also targets other proteins to the muscle sarcolemma. Among these is neuronal nitric oxide synthase (nNOSμ), which requires certain spectrin-like repeats in dystrophin's rod domain and the adaptor protein α-syntrophin to be targeted to the sarcolemma. When healthy skeletal muscle is subjected to exercise, sarcolemmal nNOSμ-derived NO attenuates local α-adrenergic vasoconstriction, thereby optimizing perfusion of muscle. We found previously that this protective mechanism is defective-causing functional muscle ischemia-in dystrophin-deficient muscles of the mdx mouse (a model of DMD) and of children with DMD, in whom nNOSμ is mislocalized to the cytosol instead of the sarcolemma. We report that this protective mechanism also is defective in men with BMD in whom the most common dystrophin mutations disrupt sarcolemmal targeting of nNOSμ. In these men, the vasoconstrictor response, measured as a decrease in muscle oxygenation, to reflex sympathetic activation is not appropriately attenuated during exercise of the dystrophic muscles. In a randomized placebo-controlled crossover trial, we show that functional muscle ischemia is alleviated and normal blood flow regulation is fully restored in the muscles of men with BMD by boosting NO-cGMP (guanosine 3',5'-monophosphate) signaling with a single dose of the drug tadalafil, a phosphodiesterase 5A inhibitor. These results further support an essential role for sarcolemmal nNOSμ in the normal modulation of sympathetic vasoconstriction in exercising human skeletal muscle and implicate the NO-cGMP pathway as a putative new target for treating BMD.

Neurochemical Architecture of the Central Complex Related to Its Function in the Control of Grasshopper Acoustic Communication

Science.gov (United States)

Kunst, Michael; Pförtner, Ramona; Aschenbrenner, Katja; Heinrich, Ralf

2011-01-01

The central complex selects and coordinates the species- and situation-specific song production in acoustically communicating grasshoppers. Control of sound production is mediated by several neurotransmitters and modulators, their receptors and intracellular signaling pathways. It has previously been shown that muscarinic cholinergic excitation in the central complex promotes sound production whereas both GABA and nitric oxide/cyclic GMP signaling suppress its performance. The present immunocytochemical and pharmacological study investigates the question whether GABA and nitric oxide mediate inhibition of sound production independently. Muscarinic ACh receptors are expressed by columnar output neurons of the central complex that innervate the lower division of the central body and terminate in the lateral accessory lobes. GABAergic tangential neurons that innervate the lower division of the central body arborize in close proximity of columnar neurons and thus may directly inhibit these central complex output neurons. A subset of these GABAergic tangential neurons accumulates cyclic GMP following the release of nitric oxide from neurites in the upper division of the central body. While sound production stimulated by muscarine injection into the central complex is suppressed by co-application of sodium nitroprusside, picrotoxin-stimulated singing was not affected by co-application of this nitric oxide donor, indicating that nitric oxide mediated inhibition requires functional GABA signaling. Hence, grasshopper sound production is controlled by processing of information in the lower division of the central body which is subject to modulation by nitric oxide released from neurons in the upper division. PMID:21980504

Tissue-Specific Control of the Endocycle by the Anaphase Promoting Complex/Cyclosome Inhibitors UVI4 and DEL1.

Science.gov (United States)

Heyman, Jefri; Polyn, Stefanie; Eekhout, Thomas; De Veylder, Lieven

2017-09-01

The endocycle represents a modified mitotic cell cycle that in plants is often coupled to cell enlargement and differentiation. Endocycle onset is controlled by activity of the Anaphase Promoting Complex/Cyclosome (APC/C), a multisubunit E3 ubiquitin ligase targeting cell-cycle factors for destruction. CELL CYCLE SWITCH52 (CCS52) proteins represent rate-limiting activator subunits of the APC/C. In Arabidopsis ( Arabidopsis thaliana ), mutations in either CCS52A1 or CCS52A2 activators result in a delayed endocycle onset, whereas their overexpression triggers increased DNA ploidy levels. Here, the relative contribution of the APC/C CCS52A1 and APC/C CCS52A2 complexes to different developmental processes was studied through analysis of their negative regulators, being the ULTRAVIOLET-B-INSENSITIVE4 protein and the DP-E2F-Like1 transcriptional repressor, respectively. Our data illustrate cooperative activity of the APC/C CCS52A1 and APC/C CCS52A2 complexes during root and trichome development, but functional interdependency during leaf development. Furthermore, we found APC/C CCS52A1 activity to control CCS52A2 expression. We conclude that interdependency of CCS52A-controlled APC/C activity is controlled in a tissue-specific manner. © 2017 American Society of Plant Biologists. All Rights Reserved.

The Dynamics of Compound, Transcript, and Protein Effects After Treatment With 2OMePS Antisense Oligonucleotides in mdx Mice

Directory of Open Access Journals (Sweden)

Ingrid E C Verhaart

2014-01-01

Full Text Available Antisense-mediated exon skipping is currently in clinical development for Duchenne muscular dystrophy (DMD to amend the consequences of the underlying genetic defect and restore dystrophin expression. Due to turnover of compound, transcript, and protein, chronic treatment with effector molecules (antisense oligonucleotides will be required. To investigate the dynamics and persistence of antisense 2′-O-methyl phosphorothioate oligonucleotides, exon skipping, and dystrophin expression after dosing was concluded, mdx mice were treated subcutaneously for 8 weeks with 100 mg/kg oligonucleotides twice weekly. Thereafter, mice were sacrificed at different time points after the final injection (36 hours–24 weeks. Oligonucleotide half-life was longer in heart (~65 days compared with that in skeletal muscle, liver, and kidney (~35 days. Exon skipping half-lives varied between 33 and 53 days, whereas dystrophin protein showed a long half-life (>100 days. Oligonucleotide and exon-skipping levels peaked in the first week and declined thereafter. By contrast, dystrophin expression peaked after 3–8 weeks and then slowly declined, remaining detectable after 24 weeks. Concordance between levels of oligonucleotides, exon skipping, and proteins was observed, except in heart, wherein high oligonucleotide levels but low exon skipping and dystrophin expression were seen. Overall, these results enhance our understanding of the pharmacokinetics and pharmacodynamics of 2′-O-methyl phosphorothioate oligos used for the treatment of DMD.

Periodic reference tracking control approach for smart material actuators with complex hysteretic characteristics

Science.gov (United States)

Sun, Zhiyong; Hao, Lina; Song, Bo; Yang, Ruiguo; Cao, Ruimin; Cheng, Yu

2016-10-01

Micro/nano positioning technologies have been attractive for decades for their various applications in both industrial and scientific fields. The actuators employed in these technologies are typically smart material actuators, which possess inherent hysteresis that may cause systems behave unexpectedly. Periodic reference tracking capability is fundamental for apparatuses such as scanning probe microscope, which employs smart material actuators to generate periodic scanning motion. However, traditional controller such as PID method cannot guarantee accurate fast periodic scanning motion. To tackle this problem and to conduct practical implementation in digital devices, this paper proposes a novel control method named discrete extended unparallel Prandtl-Ishlinskii model based internal model (d-EUPI-IM) control approach. To tackle modeling uncertainties, the robust d-EUPI-IM control approach is investigated, and the associated sufficient stabilizing conditions are derived. The advantages of the proposed controller are: it is designed and represented in discrete form, thus practical for digital devices implementation; the extended unparallel Prandtl-Ishlinskii model can precisely represent forward/inverse complex hysteretic characteristics, thus can reduce modeling uncertainties and benefits controllers design; in addition, the internal model principle based control module can be utilized as a natural oscillator for tackling periodic references tracking problem. The proposed controller was verified through comparative experiments on a piezoelectric actuator platform, and convincing results have been achieved.

Design of complex bone internal structure using topology optimization with perimeter control.

Science.gov (United States)

Park, Jaejong; Sutradhar, Alok; Shah, Jami J; Paulino, Glaucio H

2018-03-01

Large facial bone loss usually requires patient-specific bone implants to restore the structural integrity and functionality that also affects the appearance of each patient. Titanium alloys (e.g., Ti-6Al-4V) are typically used in the interfacial porous coatings between the implant and the surrounding bone to promote stability. There exists a property mismatch between the two that in general leads to complications such as stress-shielding. This biomechanical discrepancy is a hurdle in the design of bone replacements. To alleviate the mismatch, the internal structure of the bone replacements should match that of the bone. Topology optimization has proven to be a good technique for designing bone replacements. However, the complex internal structure of the bone is difficult to mimic using conventional topology optimization methods without additional restrictions. In this work, the complex bone internal structure is recovered using a perimeter control based topology optimization approach. By restricting the solution space by means of the perimeter, the intricate design complexity of bones can be achieved. Three different bone regions with well-known physiological loadings are selected to illustrate the method. Additionally, we found that the target perimeter value and the pattern of the initial distribution play a vital role in obtaining the natural curvatures in the bone internal structures as well as avoiding excessive island patterns. Copyright © 2018 Elsevier Ltd. All rights reserved.

Complex Outcomes from Insect and Weed Control with Transgenic Plants: Ecological Surprises?

Directory of Open Access Journals (Sweden)

Thomas Bøhn

2017-09-01

Full Text Available Agriculture is fundamental for human survival through food production and is performed in ecosystems that, while simplified, still operate along ecological principles and retain complexity. Agricultural plants are thus part of ecological systems, and interact in complex ways with the surrounding terrestrial, soil, and aquatic habitats. We discuss three case studies that demonstrate how agricultural solutions to pest and weed control, if they overlook important ecological and evolutionary factors, cause “surprises”: (i the fast emergence of resistance against the crop-inserted Bt-toxin in South Africa, (ii the ecological changes generated by Bt-cotton landscapes in China, and (iii the decline of the monarch butterfly, Danaus plexippus, in North America. The recognition that we work with complex systems is in itself important, as it should limit the belief in reductionist solutions. Agricultural practices lacking eco-evolutionary understanding result in “surprises” like resistance evolution both in weeds and pest insects, risking the reappearance of the “pesticide treadmill”—with increased use of toxic pesticides as the follow-up. We recommend prioritization of research that counteracts the tendencies of reductionist approaches. These may be beneficial on a short term, but with trade-off costs on a medium- to long-term. Such costs include loss of biodiversity, ecosystem services, long-term soil productivity, pollution, and reduced food quality.

Advances in complexity of beam halo-chaos and its control methods for beam transport networks

International Nuclear Information System (INIS)

Fang Jinqing

2004-11-01

The complexity theory of beam halo-chaos in beam transport networks and its control methods for a new subject of high-tech field is discussed. It is pointed that in recent years, there has been growing interest in proton beams of high power linear accelerator due to its attractive features in possible breakthrough applications in national defense and industry. In particular, high-current accelerator driven clean activity nuclear power systems for various applications as energy resources has been one of the most focusing issues in the current research, because it provides a safer, cleaner and cheaper nuclear energy resource. However, halo-chaos in high-current beam transport networks become a key concerned issue because it can generate excessive radioactivity therefore significantly limits its applications. It is very important to study the complexity properties of beam halo-chaos and to understand the basic physical mechanisms for halo chaos formation as well as to develop effective control methods for its suppression. These are very challenging subjects for the current research. The main research advances in the subjects, including experimental investigation and the oretical research, especially some very efficient control methods developed through many years of efforts of authors are reviewed and summarized. Finally, some research outlooks are given. (author)

Distributed Recurrent Neural Forward Models with Neural Control for Complex Locomotion in Walking Robots

DEFF Research Database (Denmark)

Dasgupta, Sakyasingha; Goldschmidt, Dennis; Wörgötter, Florentin

2015-01-01

here, an artificial bio-inspired walking system which effectively combines biomechanics (in terms of the body and leg structures) with the underlying neural mechanisms. The neural mechanisms consist of (1) central pattern generator based control for generating basic rhythmic patterns and coordinated......Walking animals, like stick insects, cockroaches or ants, demonstrate a fascinating range of locomotive abilities and complex behaviors. The locomotive behaviors can consist of a variety of walking patterns along with adaptation that allow the animals to deal with changes in environmental...... conditions, like uneven terrains, gaps, obstacles etc. Biological study has revealed that such complex behaviors are a result of a combination of biomechanics and neural mechanism thus representing the true nature of embodied interactions. While the biomechanics helps maintain flexibility and sustain...

The effect of a priori probability and complexity on decision making in a supervisory control task

NARCIS (Netherlands)

Kerstholt, J.H.; Passenier, P.O.; Houttuin, K.; Schuffel, H.

1996-01-01

In the present study we investigated how monitoring and fault management in a ship control task are affected by complexity and a priori probability of disturbances. Partici-pants were required to supervise four independent shipping subsystems and to adjust the subsystems whenever deviations

Biology, ecology and control of the Penthaleus species complex (Acari: Penthaleidae).

Science.gov (United States)

Umina, Paul A; Hoffmann, Ary A; Weeks, Andrew R

2004-01-01

Blue oat mites, Penthaleus spp. (Acari: Penthaleidae), are major agricultural pests in southern Australia and other parts of the world, attacking various pasture, vegetable and crop plants. Management of these mites has been complicated by the recent discovery of three cryptic pest species of Penthaleus, whereas prior research had assumed a single species. The taxonomy, population genetics, ecology, biology and control of the Penthaleus spp. complex are reviewed. Adult Penthaleus have a dark blue-black body approximately 1 mm in length, and eight red-orange legs. Within Australia, they are winter pests completing two or three generations a season, depending on conditions. The summer is passed as diapausing eggs, when long-distance dispersal is thought to occur. The Penthaleus spp. reproduce by thelytokous parthenogenesis, with populations comprising clones that differ ecologically. The three pest Penthaleus spp. differ markedly in their distributions, plant hosts, timing of diapause egg production and response to pesticides, highlighting the need to develop control strategies that consider each species separately. Chemicals are the main weapons used in current control programs, however research continues into alternative more sustainable management options. Host plant resistance, crop rotations, conservation of natural enemies, and improved timing of pesticide application would improve the management of these pests. The most cost-effective and environmentally acceptable means of control will result from the integration of these practices combined with the development of a simple field-based kit to distinguish the different mite species.

The CD63-Syntenin-1 Complex Controls Post-Endocytic Trafficking of Oncogenic Human Papillomaviruses.

Science.gov (United States)

Gräßel, Linda; Fast, Laura Aline; Scheffer, Konstanze D; Boukhallouk, Fatima; Spoden, Gilles A; Tenzer, Stefan; Boller, Klaus; Bago, Ruzica; Rajesh, Sundaresan; Overduin, Michael; Berditchevski, Fedor; Florin, Luise

2016-08-31

Human papillomaviruses enter host cells via a clathrin-independent endocytic pathway involving tetraspanin proteins. However, post-endocytic trafficking required for virus capsid disassembly remains unclear. Here we demonstrate that the early trafficking pathway of internalised HPV particles involves tetraspanin CD63, syntenin-1 and ESCRT-associated adaptor protein ALIX. Following internalisation, viral particles are found in CD63-positive endosomes recruiting syntenin-1, a CD63-interacting adaptor protein. Electron microscopy and immunofluorescence experiments indicate that the CD63-syntenin-1 complex controls delivery of internalised viral particles to multivesicular endosomes. Accordingly, infectivity of high-risk HPV types 16, 18 and 31 as well as disassembly and post-uncoating processing of viral particles was markedly suppressed in CD63 or syntenin-1 depleted cells. Our analyses also present the syntenin-1 interacting protein ALIX as critical for HPV infection and CD63-syntenin-1-ALIX complex formation as a prerequisite for intracellular transport enabling viral capsid disassembly. Thus, our results identify the CD63-syntenin-1-ALIX complex as a key regulatory component in post-endocytic HPV trafficking.

Complex dynamics of a Holling type II prey-predator system with state feedback control

International Nuclear Information System (INIS)

Jiang Guirong; Lu Qishao; Qian Linning

2007-01-01

The complex dynamics of a Holling type II prey-predator system with impulsive state feedback control is studied in both theoretical and numerical ways. The sufficient conditions for the existence and stability of semi-trivial and positive periodic solutions are obtained by using the Poincare map and the analogue of the Poincare criterion. The qualitative analysis shows that the positive periodic solution bifurcates from the semi-trivial solution through a fold bifurcation. The bifurcation diagrams, Lyapunov exponents, and phase portraits are illustrated by an example, in which the chaotic solutions appear via a cascade of period-doubling bifurcations. The superiority of the state feedback control strategy is also discussed

Future directions in controlling the LAMPF-PSR accelerator complex at Los Alamos National Laboratory

International Nuclear Information System (INIS)

Stuewe, R.; Schaller, S.; Bjorklund, E.

1992-01-01

Four interrelated projects are underway whose purpose is to migrate the LAMPF-PSR Accelerator Complex control systems to a system with a common set of hardware and software components. Project goals address problems in performance, maintenance and growth potential. Front-end hardware, operator interface hardware and software, computer systems, network systems and data system software are being simultaneously upgraded as part of these efforts. The efforts are being coordinated to provide for a smooth and timely migration to a client-server model-based data acquisition and control system. An increased use of distributed intelligence at both the front-end and the operator interface is a key element of the projects. (author)

Skeletal muscle-specific overexpression of IGFBP-2 promotes a slower muscle phenotype in healthy but not dystrophic mdx mice and does not affect the dystrophic pathology.

Science.gov (United States)

Swiderski, Kristy; Martins, Karen Janet Bernice; Chee, Annabel; Trieu, Jennifer; Naim, Timur; Gehrig, Stefan Martin; Baum, Dale Michael; Brenmoehl, Julia; Chau, Luong; Koopman, René; Gregorevic, Paul; Metzger, Friedrich; Hoeflich, Andreas; Lynch, Gordon Stuart

The insulin-like growth factor binding proteins (IGFBPs) are thought to modulate cell size and homeostasis via IGF-I-dependent and -independent pathways. There is a considerable dearth of information regarding the function of IGFBPs in skeletal muscle, particularly their role in the pathophysiology of Duchenne muscular dystrophy (DMD). In this study we tested the hypothesis that intramuscular IGFBP-2 overexpression would ameliorate the pathology in mdx dystrophic mice. 4week old male C57Bl/10 and mdx mice received a single intramuscular injection of AAV6-empty or AAV6-IGFBP-2 vector into the tibialis anterior muscle. At 8weeks post-injection the effect of IGFBP-2 overexpression on the structure and function of the injected muscle was assessed. AAV6-mediated IGFBP-2 overexpression in the tibialis anterior (TA) muscles of 4-week-old C57BL/10 and mdx mice reduced the mass of injected muscle after 8weeks, inducing a slower muscle phenotype in C57BL/10 but not mdx mice. Analysis of inflammatory and fibrotic gene expression revealed no changes between control and IGFBP-2 injected muscles in dystrophic (mdx) mice. Together these results indicate that the IGFBP-2-induced promotion of a slower muscle phenotype is impaired in muscles of dystrophin-deficient mdx mice, which contributes to the inability of IGFBP-2 to ameliorate the dystrophic pathology. The findings implicate the dystrophin-glycoprotein complex (DGC) in the signaling required for this adaptation. Copyright © 2016 Elsevier Ltd. All rights reserved.

A novel algorithm for finding optimal driver nodes to target control complex networks and its applications for drug targets identification.

Science.gov (United States)

Guo, Wei-Feng; Zhang, Shao-Wu; Shi, Qian-Qian; Zhang, Cheng-Ming; Zeng, Tao; Chen, Luonan

2018-01-19

The advances in target control of complex networks not only can offer new insights into the general control dynamics of complex systems, but also be useful for the practical application in systems biology, such as discovering new therapeutic targets for disease intervention. In many cases, e.g. drug target identification in biological networks, we usually require a target control on a subset of nodes (i.e., disease-associated genes) with minimum cost, and we further expect that more driver nodes consistent with a certain well-selected network nodes (i.e., prior-known drug-target genes). Therefore, motivated by this fact, we pose and address a new and practical problem called as target control problem with objectives-guided optimization (TCO): how could we control the interested variables (or targets) of a system with the optional driver nodes by minimizing the total quantity of drivers and meantime maximizing the quantity of constrained nodes among those drivers. Here, we design an efficient algorithm (TCOA) to find the optional driver nodes for controlling targets in complex networks. We apply our TCOA to several real-world networks, and the results support that our TCOA can identify more precise driver nodes than the existing control-fucus approaches. Furthermore, we have applied TCOA to two bimolecular expert-curate networks. Source code for our TCOA is freely available from http://sysbio.sibcb.ac.cn/cb/chenlab/software.htm or https://github.com/WilfongGuo/guoweifeng . In the previous theoretical research for the full control, there exists an observation and conclusion that the driver nodes tend to be low-degree nodes. However, for target control the biological networks, we find interestingly that the driver nodes tend to be high-degree nodes, which is more consistent with the biological experimental observations. Furthermore, our results supply the novel insights into how we can efficiently target control a complex system, and especially many evidences on the

DNA-directed control of enzyme-inhibitor complex formation: a modular approach to reversibly switch enzyme activity

NARCIS (Netherlands)

Janssen, B.M.G.; Engelen, W.; Merkx, M.

2015-01-01

DNA-templated reversible assembly of an enzyme–inhibitor complex is presented as a new and highly modular approach to control enzyme activity. TEM1-ß-lactamase and its inhibitor protein BLIP were conjugated to different oligonucleotides, resulting in enzyme inhibition in the presence of template

RFID card based access control system with counter for Indus Complex

International Nuclear Information System (INIS)

Jathar, M.R.; Vikas, Meshram; Patidar, S.C.

2015-01-01

As per norms of the Atomic energy regulatory board (AERB) to operate a facility in round the clock which has a potential of radiation exposure, radiation safety rules are to be followed. Indus -1 and Indus-2 are synchrotron radiation sources which are open for various users round the clock. To monitor the persons inside the defined zone at any given time, a system is setup consisting of RF ID cards and their readers along with dedicated software. Software is developed in Visual Basic and uses UDP network protocol for receiving data from readers installed at various locations and connected to local area network. The paper describes the access control scheme followed in Indus Accelerator Complex. (author)

Comparative In Vitro Controlled Release Studies on the Chronobiotic Hormone Melatonin from Cyclodextrins-Containing Matrices and Cyclodextrin: Melatonin Complexes.

Science.gov (United States)

Vlachou, Marilena; Papamichael, Marianna; Siamidi, Angeliki; Fragouli, Irene; Afroudakis, Pandelis A; Kompogennitaki, Rodanthi; Dotsikas, Yannis

2017-07-28

A series of hydrophilic matrix tablets was prepared and tested with respect to their ability to release the hormone melatonin in a controlled manner, in order to alleviate sleep onset and sleep maintenance dysfunctions. Besides the active ingredient, the tablets were comprised of combinations of the following: HPMC K 15M, low viscosity sodium alginate, microcrystalline cellulose (Avicel PH 102), magnesium stearate, and the cyclodextrins, α-CD, β-CD, γ-CD, HP-β-CD, sulfated β-CD, HP-α-CD and HP-γ-CD, and MLT (guest):CD (host) complexes of the above cyclodextrins, in 1:1 ratio. The controlled release studies were conducted in two aqueous dissolution media at pH 1.2 and 7.4. The stoichiometry of the formed complexes was examined by applying the continuous variation method (Job plot), while the stability constants were calculated by monitoring the spectrophotometric properties of free and CD-encapsulated melatonin (UV-Vis). Host-guest interactions were studied by Nuclear Magnetic Resonance (NMR) spectroscopy. The dissolution data suggest that melatonin is released faster from the MLT:CD complexes than from the rest matrix systems. This enhancement in the dissolution rate and the % release of melatonin from the complexes is due to the increased solubility of the MLT:CD complexes.

Design and Simulation of the Robust ABS and ESP Fuzzy Logic Controller on the Complex Braking Maneuvers

Directory of Open Access Journals (Sweden)

Andrei Aksjonov

2016-11-01

Full Text Available Automotive driving safety systems such as an anti-lock braking system (ABS and an electronic stability program (ESP assist drivers in controlling the vehicle to avoid road accidents. In this paper, ABS and the ESP, based on the fuzzy logic theory, are integrated for vehicle stability control in complex braking maneuvers. The proposed control algorithm is implemented for a sport utility vehicle (SUV and investigated for braking on different surfaces. The results obtained for the vehicle software simulator confirm the robustness of the developed control strategy for a variety of road profiles and surfaces.

The N400 and Late Positive Complex (LPC Effects Reflect Controlled Rather than Automatic Mechanisms of Sentence Processing

Directory of Open Access Journals (Sweden)

Boris Kotchoubey

2012-08-01

Full Text Available This study compared automatic and controlled cognitive processes that underlie event-related potentials (ERPs effects during speech perception. Sentences were presented to French native speakers, and the final word could be congruent or incongruent, and presented at one of four levels of degradation (using a modulation with pink noise: no degradation, mild degradation (2 levels, or strong degradation. We assumed that degradation impairs controlled more than automatic processes. The N400 and Late Positive Complex (LPC effects were defined as the differences between the corresponding wave amplitudes to incongruent words minus congruent words. Under mild degradation, where controlled sentence-level processing could still occur (as indicated by behavioral data, both N400 and LPC effects were delayed and the latter effect was reduced. Under strong degradation, where sentence processing was rather automatic (as indicated by behavioral data, no ERP effect remained. These results suggest that ERP effects elicited in complex contexts, such as sentences, reflect controlled rather than automatic mechanisms of speech processing. These results differ from the results of experiments that used word-pair or word-list paradigms.

Managing Complexity

Energy Technology Data Exchange (ETDEWEB)

Chassin, David P.; Posse, Christian; Malard, Joel M.

2004-08-01

Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today’s most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically-based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This paper explores the state of the art in the use physical analogs for understanding the behavior of some econophysical systems and to deriving stable and robust control strategies for them. In particular we review and discussion applications of some analytic methods based on the thermodynamic metaphor according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood.

The complexity of standing postural control in older adults: a modified detrended fluctuation analysis based upon the empirical mode decomposition algorithm.

Directory of Open Access Journals (Sweden)

Junhong Zhou

Full Text Available Human aging into senescence diminishes the capacity of the postural control system to adapt to the stressors of everyday life. Diminished adaptive capacity may be reflected by a loss of the fractal-like, multiscale complexity within the dynamics of standing postural sway (i.e., center-of-pressure, COP. We therefore studied the relationship between COP complexity and adaptive capacity in 22 older and 22 younger healthy adults. COP magnitude dynamics were assessed from raw data during quiet standing with eyes open and closed, and complexity was quantified with a new technique termed empirical mode decomposition embedded detrended fluctuation analysis (EMD-DFA. Adaptive capacity of the postural control system was assessed with the sharpened Romberg test. As compared to traditional DFA, EMD-DFA more accurately identified trends in COP data with intrinsic scales and produced short and long-term scaling exponents (i.e., α(Short, α(Long with greater reliability. The fractal-like properties of COP fluctuations were time-scale dependent and highly complex (i.e., α(Short values were close to one over relatively short time scales. As compared to younger adults, older adults demonstrated lower short-term COP complexity (i.e., greater α(Short values in both visual conditions (p>0.001. Closing the eyes decreased short-term COP complexity, yet this decrease was greater in older compared to younger adults (p<0.001. In older adults, those with higher short-term COP complexity exhibited better adaptive capacity as quantified by Romberg test performance (r(2 = 0.38, p<0.001. These results indicate that an age-related loss of COP complexity of magnitude series may reflect a clinically important reduction in postural control system functionality as a new biomarker.

Interactions within the yeast t-SNARE Sso1p that control SNARE complex assembly.

Science.gov (United States)

Munson, M; Chen, X; Cocina, A E; Schultz, S M; Hughson, F M

2000-10-01

In the eukaryotic secretory and endocytic pathways, transport vesicles shuttle cargo among intracellular organelles and to and from the plasma membrane. Cargo delivery entails fusion of the transport vesicle with its target, a process thought to be mediated by membrane bridging SNARE protein complexes. Temporal and spatial control of intracellular trafficking depends in part on regulating the assembly of these complexes. In vitro, SNARE assembly is inhibited by the closed conformation adopted by the syntaxin family of SNAREs. To visualize this closed conformation directly, the X-ray crystal structure of a yeast syntaxin, Sso1p, has been determined and refined to 2.1 A resolution. Mutants designed to destabilize the closed conformation exhibit accelerated rates of SNARE assembly. Our results provide insight into the mechanism of SNARE assembly and its intramolecular and intermolecular regulation.

Chemical Control for Host-Parasitoid Model within the Parasitism Season and Its Complex Dynamics

Directory of Open Access Journals (Sweden)

Tao Wang

2016-01-01

Full Text Available In the present paper, we develop a host-parasitoid model with Holling type II functional response function and chemical control, which can be applied at any time of each parasitism season or pest generation, and focus on addressing the importance of the timing of application pesticide during the parasitism season or pest generation in successful pest control. Firstly, the existence and stability of both the host and parasitoid populations extinction equilibrium and parasitoid-free equilibrium have been investigated. Secondly, the effects of key parameters on the threshold conditions have been discussed in more detail, which shows the importance of pesticide application times on the pest control. Thirdly, the complex dynamics including multiple attractors coexistence, chaotic behavior, and initial sensitivity have been studied by using numerical bifurcation analyses. Finally, the uncertainty and sensitivity of all the parameters on the solutions of both the host and parasitoid populations are investigated, which can help us to determine the key parameters in designing the pest control strategy. The present research can help us to further understand the importance of timings of pesticide application in the pest control and to improve the classical chemical control and to make management decisions.

Modified gum Arabic hydrogels as matrices for controlled release of curcumin supramolecular complexes

International Nuclear Information System (INIS)

Gerola, Adriana P.; Silva, Danielle C.; Rubira, Adley F.; Muniz, Edvani C.

2015-01-01

Modified gum Arabic (GA) hydrogels show a pH-responsive behavior making them excellent matrices to be used for oral administration of drugs. Our goal is to study the behavior of those matrices in simulated gastric and intestinal fluids. In this work we will present how the methacrylation degree of GA, by using glycidyl methacrylate, can affect the properties of these hydrogels for controlled release. The drug used in this work is the curcumin (Cur). Cur is associated with numerous pharmacological activities, but their application is limited by the low water solubility. We will present some studies involving the formation of host-guest complexes between Cur and natural cyclodextrins. Both modified GA and hydrogels were characterized by different techniques. The kinetics release of Cur complex-containing modified GA hydrogels was studied to have an insight on the release mechanism and rate constants. Toxicity studies on undifferentiated and differentiated Caco-2 were also carried out. (author)

Failure of Arm Movement Control in Stroke Patients, Characterized by Loss of Complexity.

Science.gov (United States)

Goh, Segun; Han, Kyungreem; Ryu, Jehkwang; Kim, Seonjin; Choi, MooYoung

2015-01-01

We study the mechanism of human arm-posture control by means of nonlinear dynamics and quantitative time series analysis methods. Utilizing linear and nonlinear measures in combination, we find that pathological tremors emerge in patient dynamics and serve as a main feature discriminating between normal and patient groups. The deterministic structure accompanied with loss of complexity inherent in the tremor dynamics is also revealed. To probe the underlying mechanism of the arm-posture dynamics, we further analyze the coupling patterns between joints and components, and discuss their roles in breaking of the organization structure. As a result, we elucidate the mechanisms in the arm-posture dynamics of normal subjects responding to the gravitational force and for the reduction of the dynamic degrees of freedom in the patient dynamics. This study provides an integrated framework for the origin of the loss of complexity in the dynamics of patients as well as the coupling structure in the arm-posture dynamics.

Single conversion audio amplifier and DC-AC converters with high performance and low complexity control scheme

DEFF Research Database (Denmark)

Poulsen, Søren; Andersen, Michael Andreas E.

2004-01-01

This paper proposes a novel control topology for a mains isolated single conversion audio amplifier and DC-AC converters. The topology is made for use in audio applications, and differs from prior art in terms of significantly reduced distortion as well as lower system complexity. The topology can...

Critical realism: a practical ontology to explain the complexities of smoking and tobacco control in different resource settings.

Science.gov (United States)

Oladele, Dunsi; Clark, Alexander M; Richter, Solina; Laing, Lory

2013-04-03

This paper presents critical realism (CR) as an innovative system for research in tobacco prevention and control. CR argues that underlying mechanisms are considered and explored to ensure effective implementation of any program/policy or intervention. Any intervention or program/policy that is transposed from one country to another or one setting to another is complex. The research was undertaken and analyzed through a critical ethnography lens using CR as a philosophical underpinning. The study relied upon the following components: original fieldwork in Nigeria including participant observation of smokers, in-depth interviews and focus groups with smokers, and in-depth interviews with health professionals working in the area of tobacco control in Nigeria. Findings from this small ethnographic study in Nigeria, suggest that Critical Realism holds promise for addressing underlying mechanism that links complex influences on smoking. This paper argues that understanding the underlying mechanisms associated with smoking in different societies will enable a platform for effective implementation of tobacco control policies that work in various settings.

Future directions in controlling the LAMPF-PSR Accelerator Complex at Los Alamos National Laboratory

International Nuclear Information System (INIS)

Stuewe, R.; Schaller, S.; Bjorklund, E.; Burns, M.; Callaway, T.; Carr, G.; Cohen, S.; Kubicek, D.; Harrington, M.; Poore, R.; Schultz, D.

1991-01-01

Four interrelated projects are underway whose purpose is to migrate the LAMPF-PSR Accelerator Complex control systems to a system with a common set of hardware and software components. Project goals address problems in performance, maintenance and growth potential. Front-end hardware, operator interface hardware and software, computer systems, network systems and data system software are being simultaneously upgraded as part of these efforts. The efforts are being coordinated to provide for a smooth and timely migration to a client-sever model-based data acquisition and control system. An increased use of the distributed intelligence at both the front-end and operator interface is a key element of the projects. 2 refs., 2 figs

The alternative complement pathway control protein H binds to immune complexes and serves their detection

International Nuclear Information System (INIS)

Nydegger, U.E.; Corvetta, A.; Spaeth, P.J.; Spycher, M.

1983-01-01

During solubilization of immune complexes C3b becomes fixed to the immunoglobulin part and serves as a receptor for the alternative complement pathway control protein H. The H-C3b immune complex interaction can be made detectable using 4% polyethyleneglycol to separate free from bound 125 I-H. Tetanus toxoid (Te)/anti-Te complexes kept soluble with fresh serum and containing 125 IU of specific antibody bound 18% of 125 I-H; when fresh serum was chelated with 10 mM EDTA, 125 I-H binding was only 5%. On sucrose density gradients, the H-binding material sedimented in the range of 12 to 30 S. In 36 serum samples from rheumatoid arthritis (RA) patients and in 12 serum samples from patients with systemic lupus erythematosus (SLE), 125 I-H binding was significantly elevated to 9.5 +/- 4.7% (mean +/- 1 SD) and 13.3 +/- 5.6%, respectively, while 125 I-H binding by 36 normal human sera was 4 +/- 2%. RA samples (17/36, 47%) and SLE samples (9/12, 75%) had H-binding values increased by more than 2 SD above the normal mean. The serum samples were also assessed for conglutinin- and C1q-binding activities; a significant correlation between H and C1q binding was observed (P less than 0.001); there was no correlation between H and conglutinin binding. Although binding to immune complexes through its interaction with C3b, H clearly detects a population of complexes other than conglutinin, thus expanding the possibilities of further characterizing pathological complexes

Anti-synchronization between different chaotic complex systems

International Nuclear Information System (INIS)

Liu Ping; Liu Shutang

2011-01-01

Many studies on the anti-synchronization of nonlinear real dynamic systems have been carried out, whereas the anti-synchronization of chaotic complex systems has not been studied extensively. In this work, the anti-synchronization between a new chaotic complex system and a complex Lorenz system and that between a new chaotic complex system and a complex Lue system were separately investigated by active control and nonlinear control methods, and explicit expressions were derived for the controllers that are used to achieve the anti-synchronization of chaotic complex systems. These expressions were tested numerically and excellent agreement was found. Concerning the new chaotic complex system, we discuss its dynamical properties including dissipation, chaotic behavior, fixed points, and their stability and invariance.

Cloning and chromosomal localization of the three human syntrophin genes

Energy Technology Data Exchange (ETDEWEB)

Feener, C.A.; Anderson, M.D.S.; Selig, S. [Children`s Hospital, Boston, MA (United States)] [and others

1994-09-01

Dystrophin, the protein product the Duchenne muscular dystrophy locus, is normally found to be associated with a complex of proteins. Among these dystrophin-associated proteins are the syntrophins, a group of 59 kDa membrane-associated proteins. When the syntrophins are purified based upon their association with dystrophin, they have been shown previously to form two distinct groups, the acidic ({alpha}) and basic ({beta}) forms. Based on peptide and rodent cDNA sequences, three separate syntrophin genes have been cloned and characterized from human tissues. The predicted amino acid sequences from these cDNA reveal that these proteins are related but are distinct with respect to charge, as predicted from their biochemistry. The family consists of one acidic ({alpha}-syntrophin, analogous to mouse syntrophin-1) and two basic ({beta}{sub 1}-syntrophin; and {beta}{sub 2}-syntrophin, analogous to mouse syntrophin-2) genes. Each of the three genes are widely expressed in a variety of human tissues, but the relative abundance of the three are unique with respect to each other. {alpha}-syntrophin is expressed primarily in skeletal muscle and heart as a single transcript. {beta}{sub 1}-syntrophin is expressed widely in up to five distinct transcript sizes, and is most abundant in brain. The human chromosomal locations of the three syntrophins are currently being mapped. {beta}{sub 1}-syntrophin maps to chromosome 8q23-24 and {beta}{sub 2}-syntrophin to chromosome 16. The {alpha}-syntrophin gene will be mapped accordingly. Although all three genes are candidates for neuromuscular diseases, the predominant expression of {alpha}-syntrophin in skeletal muscle and heart makes it a strong candidate to be involved in a neuromuscular disease.

Muscular dystrophy in a dog resembling human becker muscular dystrophy.

Science.gov (United States)

Baroncelli, A B; Abellonio, F; Pagano, T B; Esposito, I; Peirone, B; Papparella, S; Paciello, O

2014-05-01

A 3-year-old, male Labrador retriever dog was presented with clinical signs of progressive exercise intolerance, bilateral elbow extension, rigidity of the forelimbs, hindlimb flexion and kyphosis. Microscopical examination of muscle tissue showed marked variability in myofibre size, replacement of muscle with mature adipose tissue and degeneration/regeneration of muscle fibres, consistent with muscular dystrophy. Immunohistochemical examination for dystrophin showed markedly reduced labelling with monoclonal antibodies specific for the rod domain and the carboxy-terminal of dystrophin, while expression of β-sarcoglycan, γ-sarcoglycan and β-dystroglycan was normal. Immunoblotting revealed a truncated dystrophin protein of approximately 135 kDa. These findings supported a diagnosis of congenital canine muscular dystrophy resembling Becker muscular dystrophy in man. Copyright © 2014 Elsevier Ltd. All rights reserved.

The dynamic complexity of a three-species Beddington-type food chain with impulsive control strategy

International Nuclear Information System (INIS)

Wang Weiming; Wang Hailing; Li Zhenqing

2007-01-01

In this paper, by using theories and methods of ecology and ordinary differential equation, the dynamics complexity of a prey-predator system with Beddington-type functional response and impulsive control strategy is established. Conditions for the system to be extinct are given by using the Floquet theory of impulsive equation and small amplitude perturbation skills. Furthermore, by using the method of numerical simulation with the international software Maple, the influence of the impulsive perturbations on the inherent oscillation is investigated, which shows rich dynamics, such as quasi-periodic oscillation, narrow periodic window, wide periodic window, chaotic bands, period doubling bifurcation, symmetry-breaking pitchfork bifurcation, period-halving bifurcation and crises, etc. The numerical results indicate that computer simulation is a useful method for studying the complex dynamic systems

The use of picture cues to establish self-control in the preparation of complex meals by mentally retarded adults.

Science.gov (United States)

Martin, J E; Rusch, F R; James, V L; Decker, P J; Trtol, K A

1982-01-01

This investigation examined the effectiveness of picture cues in establishing self-control in the completion of complex meals by mildly and moderately retarded adults. Three participants, who lived in nonsheltered residential settings, were trained to prepare five complex meals. Following a training baseline comprised of pre-instruction, instructional feedback, and trainers' presence, picture recipe cards were introduced in a multiple-baseline fashion. Rapid improvement in the ability of each participant to independently complete each meal when the picture recipe cards were used occurred. A return to baseline for one of the participants demonstrated further self-directed antecedent stimulus control of the picture recipe cards as an effective treatment procedure. A discussion of future areas of research is included.

A multiple-shape memory polymer-metal composite actuator capable of programmable control, creating complex 3D motion of bending, twisting, and oscillation

Science.gov (United States)

Shen, Qi; Trabia, Sarah; Stalbaum, Tyler; Palmre, Viljar; Kim, Kwang; Oh, Il-Kwon

2016-04-01

Development of biomimetic actuators has been an essential motivation in the study of smart materials. However, few materials are capable of controlling complex twisting and bending deformations simultaneously or separately using a dynamic control system. Here, we report an ionic polymer-metal composite actuator having multiple-shape memory effect, and is able to perform complex motion by two external inputs, electrical and thermal. Prior to the development of this type of actuator, this capability only could be realized with existing actuator technologies by using multiple actuators or another robotic system. This paper introduces a soft multiple-shape-memory polymer-metal composite (MSMPMC) actuator having multiple degrees-of-freedom that demonstrates high maneuverability when controlled by two external inputs, electrical and thermal. These multiple inputs allow for complex motions that are routine in nature, but that would be otherwise difficult to obtain with a single actuator. To the best of the authors’ knowledge, this MSMPMC actuator is the first solitary actuator capable of multiple-input control and the resulting deformability and maneuverability.

A multiple-shape memory polymer-metal composite actuator capable of programmable control, creating complex 3D motion of bending, twisting, and oscillation.

Science.gov (United States)

Shen, Qi; Trabia, Sarah; Stalbaum, Tyler; Palmre, Viljar; Kim, Kwang; Oh, Il-Kwon

2016-04-15

Development of biomimetic actuators has been an essential motivation in the study of smart materials. However, few materials are capable of controlling complex twisting and bending deformations simultaneously or separately using a dynamic control system. Here, we report an ionic polymer-metal composite actuator having multiple-shape memory effect, and is able to perform complex motion by two external inputs, electrical and thermal. Prior to the development of this type of actuator, this capability only could be realized with existing actuator technologies by using multiple actuators or another robotic system. This paper introduces a soft multiple-shape-memory polymer-metal composite (MSMPMC) actuator having multiple degrees-of-freedom that demonstrates high maneuverability when controlled by two external inputs, electrical and thermal. These multiple inputs allow for complex motions that are routine in nature, but that would be otherwise difficult to obtain with a single actuator. To the best of the authors' knowledge, this MSMPMC actuator is the first solitary actuator capable of multiple-input control and the resulting deformability and maneuverability.

Fabrication of advanced Bragg gratings with complex apodization profiles by use of the polarization control method

DEFF Research Database (Denmark)

Deyerl, Hans-Jürgen; Plougmann, Nikolai; Jensen, Jesper Bo Damm

2004-01-01

The polarization control method offers a flexible, robust, and low-cost route for the parallel fabrication of gratings with complex apodization profiles including several discrete phase shifts and chirp. The performance of several test gratings is evaluated in terms of their spectral response...... and compared with theoretical predictions. Short gratings with sidelobe-suppression levels in excess of 32 dB and transmission dips lower than 80 dB have been realized. Finally, most of the devices fabricated by the polarization control method show comparable quality to gratings manufactured by far more...

Dysfunctional Muscle and Liver Glycogen Metabolism in mdx Dystrophic Mice

Science.gov (United States)

Stapleton, David I.; Lau, Xianzhong; Flores, Marcelo; Trieu, Jennifer; Gehrig, Stefan M.; Chee, Annabel; Naim, Timur; Lynch, Gordon S.; Koopman, René

2014-01-01

Background Duchenne muscular dystrophy (DMD) is a severe, genetic muscle wasting disorder characterised by progressive muscle weakness. DMD is caused by mutations in the dystrophin (dmd) gene resulting in very low levels or a complete absence of the dystrophin protein, a key structural element of muscle fibres which is responsible for the proper transmission of force. In the absence of dystrophin, muscle fibres become damaged easily during contraction resulting in their degeneration. DMD patients and mdx mice (an animal model of DMD) exhibit altered metabolic disturbances that cannot be attributed to the loss of dystrophin directly. We tested the hypothesis that glycogen metabolism is defective in mdx dystrophic mice. Results Dystrophic mdx mice had increased skeletal muscle glycogen (79%, (Pglycogen synthesis is initiated by glycogenin, the expression of which was increased by 50% in mdx mice (PGlycogen synthase activity was 12% higher (Pglycogen branching enzyme activity was 70% lower (Pglycogen breakdown, glycogen phosphorylase, had 62% lower activity (Pglycogen debranching enzyme expression was 50% higher (Pglycogen (Pglycogen metabolism in mdx mice identified reduced glycogenin protein expression (46% less; Pglycogen but reduced amounts of liver glycogen. PMID:24626262

The phylogenomic analysis of the anaphase promoting complex and its targets points to complex and modern-like control of the cell cycle in the last common ancestor of eukaryotes

Directory of Open Access Journals (Sweden)

Brochier-Armanet Céline

2011-09-01

Full Text Available Abstract Background The Anaphase Promoting Complex or Cyclosome (APC/C is the largest member of the ubiquitin ligase [E3] family. It plays a crucial role in the control of the cell cycle and cell proliferation by mediating the proteolysis of key components by the proteasome. APC/C is made of a dozen subunits that assemble into a large complex of ~1.5 MDa, which interacts with various cofactors and targets. Results Using comparative genomic and phylogenetic approaches, we showed that 24 out of 37 known APC/C subunits, adaptors/co-activators and main targets, were already present in the Last Eukaryotic Common Ancestor (LECA and were well conserved to a few exceptions in all present-day eukaryotic lineages. The phylogenetic analysis of the 24 components inferred to be present in LECA showed that they contain a reliable phylogenetic signal to reconstruct the phylogeny of the domain Eucarya. Conclusions Taken together our analyses indicated that LECA had a complex and highly controlled modern-like cell cycle. Moreover, we showed that, despite what is generally assumed, proteins involved in housekeeping cellular functions may be a good complement to informational genes to study the phylogeny of eukaryotes.

Constructing Asymmetric Polyion Complex Vesicles via Template Assembling Strategy: Formulation Control and Tunable Permeability

Directory of Open Access Journals (Sweden)

Junbo Li

2017-11-01

Full Text Available A strategy for constructing polyion complex vesicles (PICsomes with asymmetric structure is described. Poly(methylacrylic acid-block-poly(N-isopropylacrylamide modified gold nanoparticles (PMAA-b-PNIPAm-@-Au NPs were prepared and then assembled with poly(ethylene glycol-block-poly[1-methyl-3-(2-methacryloyloxy propylimidazolium bromine] (PEG-b-PMMPImB via polyion complex of PMMA and PMMPImB. After removing the Au NPs template, asymmetric PICsomes composed of a PNIPAm inner-shell, PIC wall, and PEG outer-corona were obtained. These PICsomes have low protein absorption and thermally tunable permeability, provided by the PEG outer-corona and the PNIPAm inner-shell, respectively. Moreover, PICsome size can be tailored by using templates of predetermined sizes. This novel strategy for constructing asymmetric PICsomes with well-defined properties and controllable size is valuable for applications such as drug delivery, catalysis and monitoring of chemical reactions, and biomimetics.

Central Arterial Function Measured by Non-invasive Pulse Wave Analysis is Abnormal in Patients with Duchenne Muscular Dystrophy.

Science.gov (United States)

Ryan, Thomas D; Parent, John J; Gao, Zhiqian; Khoury, Philip R; Dupont, Elizabeth; Smith, Jennifer N; Wong, Brenda; Urbina, Elaine M; Jefferies, John L

2017-08-01

Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder caused by mutation of dystrophin. Cardiovascular involvement includes dilated cardiomyopathy. Non-invasive assessment of vascular function has not been evaluated in DMD. We hypothesize arterial wave reflection is abnormal in patients with DMD. Pulse wave analysis was performed on DMD patients with a SphygmoCor SCOR-PVx System to determine central blood pressure and augmentation index (AIx) as an assessment of arterial wave reflection. Results were compared to a control group. A total of 43 patients with DMD were enrolled, and compared to 43 normal controls. Central systolic blood pressure was lower, while both AIx-75 (7.8 ± 9.6% vs. 2.1 ± 10.4%, p 0.01, DMD vs. normal) and AIx-not corrected (16.8 ± 10.1% vs. -3.6 ± 10.9, p wave reflection when compared to normal controls, which may represent increased arterial stiffness. Overall there appears to be no effect on ventricular systolic function, however the long-term consequence in this group is unknown. Further study is required to determine the mechanism of these differences, which may be related to the effects of systemic steroids or the role of dystrophin in vascular function.

Control of Genome Integrity by RFC Complexes; Conductors of PCNA Loading onto and Unloading from Chromatin during DNA Replication

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Yasushi Shiomi

2017-01-01

Full Text Available During cell division, genome integrity is maintained by faithful DNA replication during S phase, followed by accurate segregation in mitosis. Many DNA metabolic events linked with DNA replication are also regulated throughout the cell cycle. In eukaryotes, the DNA sliding clamp, proliferating cell nuclear antigen (PCNA, acts on chromatin as a processivity factor for DNA polymerases. Since its discovery, many other PCNA binding partners have been identified that function during DNA replication, repair, recombination, chromatin remodeling, cohesion, and proteolysis in cell-cycle progression. PCNA not only recruits the proteins involved in such events, but it also actively controls their function as chromatin assembles. Therefore, control of PCNA-loading onto chromatin is fundamental for various replication-coupled reactions. PCNA is loaded onto chromatin by PCNA-loading replication factor C (RFC complexes. Both RFC1-RFC and Ctf18-RFC fundamentally function as PCNA loaders. On the other hand, after DNA synthesis, PCNA must be removed from chromatin by Elg1-RFC. Functional defects in RFC complexes lead to chromosomal abnormalities. In this review, we summarize the structural and functional relationships among RFC complexes, and describe how the regulation of PCNA loading/unloading by RFC complexes contributes to maintaining genome integrity.

A dystrophic Duchenne mouse model for testing human antisense oligonucleotides.

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Marcel Veltrop

Full Text Available Duchenne muscular dystrophy (DMD is a severe muscle-wasting disease generally caused by reading frame disrupting mutations in the DMD gene resulting in loss of functional dystrophin protein. The reading frame can be restored by antisense oligonucleotide (AON-mediated exon skipping, allowing production of internally deleted, but partially functional dystrophin proteins as found in the less severe Becker muscular dystrophy. Due to genetic variation between species, mouse models with mutations in the murine genes are of limited use to test and further optimize human specific AONs in vivo. To address this we have generated the del52hDMD/mdx mouse. This model carries both murine and human DMD genes. However, mouse dystrophin expression is abolished due to a stop mutation in exon 23, while the expression of human dystrophin is abolished due to a deletion of exon 52. The del52hDMD/mdx model, like mdx, shows signs of muscle dystrophy on a histological level and phenotypically mild functional impairment. Local administration of human specific vivo morpholinos induces exon skipping and dystrophin restoration in these mice. Depending on the number of mismatches, occasional skipping of the murine Dmd gene, albeit at low levels, could be observed. Unlike previous models, the del52hDMD/mdx model enables the in vivo analysis of human specific AONs targeting exon 51 or exon 53 on RNA and protein level and muscle quality and function. Therefore, it will be a valuable tool for optimizing human specific AONs and genome editing approaches for DMD.