The rev-erbAalpha orphan protein belongs to the steroid nuclear receptor superfamily. No ligand has been identified for this protein, and little is known of its function in development or physiology. In this study, we focus on 1) the distribution of the rev-erbAalpha protein in adult fast- and slow-twitch skeletal muscles and muscle fibers and 2) how the rev-erbAalpha protein influences myosin heavy chain (MyHC) isoform expression in mice heterozygous (+/-) and homozygous (-/-) for a rev-erbAalpha protein null allele. In the fast-twitch extensor digitorum longus muscle, rev-erbAalpha protein expression was linked to muscle fiber type; however, MyHC isoform expression did not differ between wild-type, +/-, or -/- mice. In the slow-twitch soleus muscle, the link between rev-erbAalpha protein and MyHC isoform expression was more complex than in the extensor digitorum longus. Here, a significantly higher relative amount of the beta/slow (type I) MyHC isoform was observed in both rev-erbAalpha -/- and +/- mice vs. that shown in wild-type controls. A role for the ratio of thyroid hormone receptor proteins alpha1 to alpha2 in modulating MyHC isoform expression can be ruled out because no differences were seen in MyHC isoform expression between thyroid hormone receptor alpha2-deficient mice (heterozygous and homozygous) and wild-type mice. Therefore, our data are compatible with the rev-erbAalpha protein playing an important role in the regulation of skeletal muscle MyHC isoform expression.

Expression of myosin isoforms in skeletal muscles in mice lacking the rev-erb Alpha orphan receptor

Rodent motor units, muscle fibers, and motor proteins undergo significant aging-related changes. Such changes include spatial organization and physiological properties of fast- and slow-twitch single motor units, regulation of contractile speed and force generation capacity at the muscle fiber level, and altered functional properties of the motor protein myosin. In addition to specific changes, there also appears to be a "disorganization" of the coordinated expression of contractile, sarcoplasmic reticular, and mitochondrial protein isoforms in aging skeletal muscle. This is suggested to have a strong impact on aging-related impairments in muscle function in addition to the changes in specific muscle proteins.

A decrease in specific tension (SpT), or force per unit cross-sectional area of skeletal muscle, in the elderly is well documented. This decrease may be due to a decrease in the number of acto-myosin interactions, a decrease in the force per acto-myosin interaction, or a combination of both of these. We hypothesized that a decrease in the concentration of the contractile proteins would be, at least in part, responsible for the decrease in SpT observed in the elderly. To test this hypothesis, the actin and myosin heavy chain (MyHC) concentration was determined from 73 single muscle fibers from a group of young men (18–25 years) and 72 muscle fibers from old men (65–80 years). The volume of fluorescent-labeled single muscle fibers was measured using confocal microscopy and the contractile protein content was determined using SDS-PAGE with Commassie Blue staining and soft laser densitometry. The main findings of the study were as follows: 1) An aging-related decrease in muscle fiber cross-sectional area, affecting primarily muscle fibers expressing fast MyHC isoforms (Young: 4,695 ± 170μm2 vs. Old: 4,332 ± 124 μm2); 2) A significant aging-related loss of MyHC, but not actin, per unit of cell volume (MyHC: Young: 95.6 ± 4.6 O. D. units vs. Old: 87.2 ± 5.3 O. D. units). There were no differences detected in actin concentration. These data demonstrate that the decrease in SpT in the elderly is, at least in part due to a decrease in the concentration of the molecular motor protein, myosin.

Foreword. Acknowledgements. List of Tables. List of Figures. The Evolution of Broadcasting. The Internet. Broadcasting Meets the Internet. Technology Framework for Data Broadcasting Environments. The Five Basic Formats of Data Broadcasting. Implementing a Data Broadcasting Platform. Data Broadcasting: The Media Opportunities. Creating Data Broadcasting Applications and Services: 26 Steps. Operating Networks of Multiple Data Broadcasting Channels. The Commercial Drivers Behind Data Broadcasting. Data Broadcasting in the Future. Glossary of Terms. Index.

Autologous peripheral blood stem cell transplantation (APSCT) is increasingly used in the treatment of breast cancer. We report a patient who experienced septic shock, and after treatment with antibiotics, high-dose corticosteroids and mechanical ventilation due to respiratory insufficiency, developed quadriplegia. Electroneurophysiological examination, as well as a muscle biopsy, showed a typical picture of acute quadriplegic myopathy with loss of thick filament proteins. This is, to the best of our knowledge, the first reported case of this complication following APSCT.

The rat is the most extensively characterized species with regard to the regulation of muscle contraction and myofibrillar protein isoform expression, but there is reason to question whether results from small mammals, such as the rat, can be extrapolated directly to larger mammals, such as man. Studies of human muscle contraction have primarily used different in vivo muscle function measurements, i.e. measurements of force at different speeds of movement during electrical stimulation or voluntary activation. These measurements give important information on overall muscle function, but they are of limited value for our understanding of regulation of muscle contraction. In basic science, cellular- and molecular-physiological methods have been used for many years, but these techniques have so far only rarely been used in studies of human muscle contraction. Detailed studies of human muscle contraction can be performed in the short muscle fibre segments obtained by the percutaneous muscle biopsy technique both at the cellular and molecular level. The skinned fibre preparation in combination with a novel in vitro motility assay offers a unique possibility to investigate regulation of human muscle contraction at the cellular and molecular levels in the same muscle cell segment in both health and disease, i.e. in muscle cells characterized according to the type amount of expressed myofibrillar protein isoforms.

article Free Access Share on An object-oriented structured design method for code generation Authors: A. I. Wasserman Interactive Development Environments, Inc., 595 Market Street, 12th floor, San Francisco, CA Interactive Development Environments, Inc., 595 Market Street, 12th floor, San Francisco, CAView Profile , Peter Pircher nteractive Development Environments, Inc., 595 Market Street, 12th floor, San Francisco, CA nteractive Development Environments, Inc., 595 Market Street, 12th floor, San Francisco, CAView Profile , R. J. Muller nteractive Development Environments, Inc., 595 Market Street, 12th floor, San Francisco, CA nteractive Development Environments, Inc., 595 Market Street, 12th floor, San Francisco, CAView Profile Authors Info & Claims ACM SIGSOFT Software Engineering NotesVolume 14Issue 1Jan. 1989 pp 32–55https://doi.org/10.1145/66051.66053Online:03 January 1989Publication History 38citation340DownloadsMetricsTotal Citations38Total Downloads340Last 12 Months5Last 6 weeks1 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF

Die vorliegende Arbeit hat zum Ziel, die Anwendbarkeit von analytischen Verfahren und der Simulationstechnik zur Behandlung aktueller Problemstellungen in der Praxis der Leistungsanalyse von Computersystemen zu diskutieren. An einem Beispiel wird dann das uns für viele Fälle geeignet erscheinende hybride Verfahren gezeigt und die damit mögliche Flexibilität erläutert; gleichzeitig weisen wir aber auch auf die dabei entstehenden Probleme hin.

Die ständig steigende Komplexität der Computersysteme und ihres Einsatzes in der Praxis führt dazu, dass aussagekräftige Daten über deren Verhalten unter verschiedenen Belastungen immer wichtiger werden. Diese sollen Auskunft darüber geben, wie und durch was die einzelnen Resourcen beansprucht werden (Abrechnung), wie sich die Computerbelastung entwickelt (Trendanalyse), wie das System besser abgestimmt werden kann (Tuning) und schliesslich sollten sie gestatten, die Auswirkungen von Konfigurations- und Belastungsänderungen zu evaluieren. Zu den schon in diesem Spannungsfeld anstehenden vielschichtigen Fragestellungen kommt nun aber noch die “Was, wenn”-Problematik hinzu, welche die Vorhersage der Auswirkungen von Entwicklungsentscheidungen und von Systemänderungen verlangt. Die hier aufgeworfenen Fragen sind jedoch meistens nicht durch Interpolation und Extrapolation von Messdaten zufriedenstellend zu beantworten, und es sind deshalb weitere Verfahren und Hilfsmittel erforderlich, welche eine zweckmässige Vorhersage des Systemverhaltens gestatten.