Stable Carbon Isotopes (δ 13C) in Coral Skeletons: Experimental Approach and Applications for Paleoceanography

Science.gov (United States)

Grottoli, A. G.

2004-12-01

Scleractinian corals obtain fixed carbon via photosynthesis by their endosymbiotic algae (zooxanthellae) and via hetertrophy (injestion of zooplankton, δ 13C ≈ -17 to -22‰ ). Carbon dioxide (CO2) used for photosynthesis is obtained from seawater (δ 13C ≈ 0%) or from respired CO2 within the coral host. The δ 13C of the carbon used in the formation of the underlying coral skeleton is fractionated as a result of both of these metabolic processes. Here I have pooled evidence from several field and tank experiments on the effect of photosynthesis and heterotrophy of coral skeletal δ 13C. In the experiments, decreases in light levels due to shading or depth resulted in a significant decrease in skeletal δ 13C in all species studied (Pavona gigantea, Pavona clavus, Porites compressa). Decreases in photosynthesis in bleached corals also resulted in a decrease in skeletal δ 13C compared to non-bleached corals growing under the same conditions and at the same location. Skeletal δ 13C also decreased at higher than normal light levels most likely due to photoinhibition. Thus, decreases in photosynthesis due to reduced light levels, due to bleaching-induced decreases in chlorophyll a concentrations, or due to photodamage-induced decreases in functional cholorphyll a, results in significant δ 13C decreases. Comprehensive interpretation of all of the data showed that changes in photosynthesis itself can drive the changes in δ 13C. In field experiments, the addition of natural concentrations of zooplankton to the diet resulted in decreases in skeletal δ 13C. Such a decrease was more pronounced with depth and in P. gigantea compared to P. clavus. In situ feeding experiments have since confirmed these findings. However under tank conditions with unaturally high feeding rates, enhanced nitrogen supply in the diet can disrupt the coral-algal symbiosis, stimlate zooxanthellae growth and photosynthesis, and cause an incrase in skeletal δ 13C. It is proposed that under

Radiographic diagnosis of skeletal diseases among dogs in Lagos ...

African Journals Online (AJOL)

Case records of dogs presented with signs of skeletal injuries at the Veterinary Teaching Hospital, Federal University of Agriculture, Abeokuta, Ogun State and Petcare Animal Hospital, Ikeja, Lagos between January, 2010 and December, 2011 were reviewed. Data recorded included breed, sex and age of the dogs, ...

Systemic Administration of Carbon Monoxide-Releasing Molecule-3 Protects the Skeletal Muscle in Porcine Model of Compartment Syndrome.

Science.gov (United States)

Bihari, Aurelia; Cepinskas, Gediminas; Sanders, David; Lawendy, Abdel-Rahman

2018-05-01

Acute limb compartment syndrome, a complication of musculoskeletal trauma, results in muscle necrosis and cell death. Carbon monoxide, liberated from the carbon monoxide-releasing molecule-3, has been shown protective in a rat model of compartment syndrome. The purpose of this study was to test the effect of carbon monoxide-releasing molecule-3 in a preclinical large animal model of compartment syndrome, with the ultimate goal of developing a pharmacologic adjunct treatment for compartment syndrome. Animal research study. Basic research laboratory in a hospital setting. Male Yorkshire-Landrace pigs (50-60 kg). Pigs underwent 6 hours of intracompartmental pressure elevation by infusing fluid into the anterior compartment of the right hind limb. Carbon monoxide-releasing molecule-3 was administered systemically (2 mg/kg, IV) at fasciotomy, followed by 3-hour reperfusion. Muscle perfusion, inflammation, injury, and apoptosis were assessed in the skeletal muscle. Systemic leukocyte activation was assessed during compartment syndrome and reperfusion. Elevation of hind limb intracompartmental pressure resulted in significant microvascular perfusion deficits (44% ± 1% continuously perfused capillaries in compartment syndrome vs 76% ± 4% in sham; p molecule-3 at fasciotomy increased the number of continuously perfused capillaries (68% ± 3%; p molecule-3 at fasciotomy offered protection against compartment syndrome-induced microvascular perfusion deficit, tissue injury, and systemic leukocyte activation. The data suggest the potential therapeutic application of carbon monoxide-releasing molecule-3 to patients at risk of developing compartment syndrome.

Toward explaining the Holocene carbon dioxide and carbon isotope records: Results from transient ocean carbon cycle-climate simulations

Science.gov (United States)

Menviel, L.; Joos, F.

2012-03-01

The Bern3D model was applied to quantify the mechanisms of carbon cycle changes during the Holocene (last 11,000 years). We rely on scenarios from the literature to prescribe the evolution of shallow water carbonate deposition and of land carbon inventory changes over the glacial termination (18,000 to 11,000 years ago) and the Holocene and modify these scenarios within uncertainties. Model results are consistent with Holocene records of atmospheric CO2 and δ13C as well as the spatiotemporal evolution of δ13C and carbonate ion concentration in the deep sea. Deposition of shallow water carbonate, carbonate compensation of land uptake during the glacial termination, land carbon uptake and release during the Holocene, and the response of the ocean-sediment system to marine changes during the termination contribute roughly equally to the reconstructed late Holocene pCO2 rise of 20 ppmv. The 5 ppmv early Holocene pCO2 decrease reflects terrestrial uptake largely compensated by carbonate deposition and ocean sediment responses. Additional small contributions arise from Holocene changes in sea surface temperature, ocean circulation, and export productivity. The Holocene pCO2 variations result from the subtle balance of forcings and processes acting on different timescales and partly in opposite direction as well as from memory effects associated with changes occurring during the termination. Different interglacial periods with different forcing histories are thus expected to yield different pCO2 evolutions as documented by ice cores.

Unlocking the coral calcification process: Insights from boron isotope measurements and a skeletal growth model

Science.gov (United States)

Mollica, N. R.; Guo, W.; Cohen, A. L.; Huang, K. F.; Foster, G. L.; Donald, H.; Solow, A.

2017-12-01

Carbonate skeletons of scleractinian corals are important archives of ocean climate and environmental change. However, corals don't accrete their skeletons directly from ambient seawater, but from a calcifying fluid whose composition is strongly regulated. There is mounting evidence that the carbonate chemistry of this calcifying fluid significantly impacts the amount of carbonate the coral can precipitate, which in turn affects the geochemical composition of the skeleton produced. However the mechanistic link between calcifying fluid (cf) chemistry, particularly the up-regulation of pHcf and thereby aragonite saturation state (Ωcf), and coral calcification is not well understood. We explored this link by combining boron isotope measurements with in situ measurements of seawater temperature, salinity, and DIC to estimate Ωcf of nine Porites corals from four Pacific reefs. Associated calcification rates were quantified for each core via CT scanning. We do not observe a relationship between calcification rates and Ωcf or Ωsw. Instead, when we deconvolve calcification into linear extension and skeletal density, a significant correlation is observed between density and Ωcf, and also Ωsw while extension does not correlate with either. These observations are consistent with the two-step model of coral calcification, in which skeleton is secreted in two distinct phases: vertical extension creating new skeletal elements, followed by lateral thickening of existing elements that are covered by living tissue. We developed a numerical model of Porites skeletal growth that builds on this two-step model and links skeletal density with the external seawater environment via its influence on the chemistry of coral calcifying fluid. We validated the model using existing coral skeletal datasets from six Porites species collected across five reef sites, and quantified the effects of each seawater parameter (e.g. temperature, pH, DIC) on skeletal density. Our findings illustrate

A 40 ka high-resolution soil carbonate record from southern Utah: proxy development, paleohydrology, and paleoecology

Science.gov (United States)

Huth, T.; Cerling, T. E.; Marchetti, D. W.; Fernandez, D. P.; Mackey, G. N., III; Bowling, D. R.; Passey, B. H.

2017-12-01

Terrestrial paleoclimate records are critically important for testing hypotheses of climate dynamics and verifying climate simulations. However, unlike their oceanic counterparts, terrestrial records are short, more commonly discontinuous, and require specific geographic conditions not necessarily ideal for proposed questions (e.g., speleothem records must come from wherever a cave occurs). We instead utilize laminated soil carbonate rinds as a high resolution (100s yr) paleoclimate archive. Soil carbonate rinds can represent 10s-100s kyr, are apparently continuous over relevant timescales, maintain stratigraphic order, and are common in arid and semi-arid regions. We demonstrate the utility of this methodology at Torrey, Utah which is at the northern edge of the North American Monsoon (NAM). Sample rinds form on the bottom of large (≈1 m) boulders. The rinds are 0.5-2 cm thick and have visually and microscopically identifiable stratigraphy. Radiocarbon dates are in order and suggest a nearly constant growth rate from ≈40 ka to 3 ka, when the record ends. However, the pendants have significant pore space, so secondary carbonate has the potential to bias sample ages to be too young by 100s-1000s years. Precise sampling may be able to mitigate this bias. In spite of the potential secondary carbonate bias, δ13C and δ18O analyses show trends consistent with regional records. Secondary carbonate is therefore a concern, but apparently does not overpower the primary isotopic signals. A calibration study identified soil carbonate formation during the peak growing season (i.e., JAS, during the NAM), so we interpret our records as summer signals modulated by soil `memory' effects. The δ18O record has low variability (±0.5 ‰) but mimics regional NAM records, suggesting similar climate drivers as far north as Utah. The δ13C record shows some correlation with δ18O, which is reasonable given that the strength of the NAM can drive ecologic responses. However, the data

Skeletal coccidioidomycosis: imaging findings in 19 patients

International Nuclear Information System (INIS)

Zeppa, M.A.; Greenspan, A.; McGahan, J.P.; Laorr, A.; Steinbach, L.S.

1996-01-01

The objective of this study was to describe the distribution and radiologic appearance of skeletal coccidioidomycosis in 19 documented cases. Medical records of 19 patients with clinically confirmed skeletal occidioidomycosis were retrospectively reviewed. The patients were studied with plain radiography, skeletal scintigraphy and MRI. Multiple lesions were seen in 11 of 19 patients (58%). Of a total of 46 lesions, 27 (59%) were described as punched-out lytic, 10 (22%) as permeative/destructive, and 9 (17%) as involving a joint and/or disk space. Lesions were identified in almost every bone (with the exception of the facial bones, ulna, carpus, and fibula) and were most commonly found in the axial skeleton (20 of 46; 43%). Plain radiographs are effective in the initial evaluation of bones and joints, scintigraphic studies can identify disseminated disease, and CT and MRI are effective in determining soft tissue involvement and spinal abnormalities. (orig./MG)

Exohedral and skeletal rearrangements in the molecules of fullerene derivatives

Energy Technology Data Exchange (ETDEWEB)

Ignat' eva, Daria V; Ioffe, I N; Troyanov, Sergey I; Sidorov, Lev N [Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

2011-07-31

The data on the migration of monoatomic addends, perfluoroalkyl and more complex organic groups in the molecules of fullerene derivatives published mainly in the last decade are analyzed. Skeletal rearrangements of the carbon cage occurring during chemical reactions are considered.

Could a secular increase in organic burial explain the rise of oxygen? Insights from a geological carbon cycle model constrained by the carbon isotope record

Science.gov (United States)

Krissansen-Totton, J.; Kipp, M.; Catling, D. C.

2017-12-01

The stable isotopes of carbon in marine sedimentary rock provide a window into the evolution of the Earth system. Conventionally, a relatively constant carbon isotope ratio in marine sedimentary rocks has been interpreted as implying constant organic carbon burial relative to total carbon burial. Because organic carbon burial corresponds to net oxygen production from photosynthesis, it follows that secular changes in the oxygen source flux cannot explain the dramatic rise of oxygen over Earth history. Instead, secular declines in oxygen sink fluxes are often invoked as causes for the rise of oxygen. However, constant fractional organic burial is difficult to reconcile with tentative evidence for low phosphate concentrations in the Archean ocean, which would imply lower marine productivity and—all else being equal—less organic carbon burial than today. The conventional interpretation of the carbon isotope record rests on the untested assumption that the isotopic ratio of carbon inputs into the ocean reflect mantle isotopic values throughout Earth history. In practice, differing rates of carbonate and organic weathering will allow for changes in isotopic inputs, as suggested by [1] and [2]. However, these inputs can not vary freely because large changes in isotopic inputs would induce secular trends in carbon reservoirs, which are not observed in the isotope record. We apply a geological carbon cycle model to all Earth history, tracking carbon isotopes in crustal, mantle, and ocean reservoirs. Our model is constrained by the carbon isotope record such that we can determine the extent to which large changes in organic burial are permitted. We find both constant organic burial and 3-5 fold increases in organic burial since 4.0 Ga can be reconciled with the carbon isotope record. Changes in the oxygen source flux thus need to be reconsidered as a possible contributor to Earth's oxygenation. [1] L. A. Derry, Organic carbon cycling and the lithosphere, in Treatise on

Microfluidic Actuation of Carbon Nanotube Fibers for Neural Recordings

Science.gov (United States)

Vercosa, Daniel G.

Implantable devices to record and stimulate neural circuits have led to breakthroughs in neuroscience; however, technologies capable of electrical recording at the cellular level typically rely on rigid metals that poorly match the mechanical properties of soft brain tissue. As a result these electrodes often cause extensive acute and chronic injury, leading to short electrode lifetime. Recently, flexible electrodes such as Carbon Nanotube fibers (CNTf) have emerged as an attractive alternative to conventional electrodes and studies have shown that these flexible electrodes reduce neuro-inflammation and increase the quality and longevity of neural recordings. Insertion of these new compliant electrodes, however, remains challenge. The stiffening agents necessary to make the electrodes rigid enough to be inserted increases device footprint, which exacerbates brain damage during implantation. To overcome this challenge we have developed a novel technology to precisely implant and actuate high-performance, flexible carbon nanotube fiber (CNTf) microelectrodes without using a stiffening agents or shuttles. Instead, our technology uses drag forces within a microfluidic device to drive electrodes into tissue while minimizing the amount of fluid that is ejected into the tissue. In vitro experiments in brain phantoms, show that microfluidic actuated CNTf can be implanted at least 4.5 mm depth with 30 microm precision, while keeping the total volume of fluid ejected below 0.1 microL. As proof of concept, we inserted CNTfs in the small cnidarian Hydra littoralis and observed compound action potentials corresponding to contractions and in agreement with the literature. Additionally, brain slices extracted from transgenic mice were used to show that our device can be used to record spontaneous and light evoked activity from the cortex and deep brain regions such as the thalamic reticular nucleus (TRN). Overall our microfluidic actuation technology provides a platform for

Bryozoans as indicators of global change: predictable shifts in morphology and carbonate mineralogy in response to warming and ocean acidification

Science.gov (United States)

Swezey, D. S.; Bean, J. R.; Ninokawa, A. T.; Sanford, E.

2014-12-01

Recent studies have documented variation in skeletal structure and carbonate mineralogy across a broad range of marine invertebrate taxa. Intraspecific changes in growth, morphology, and carbonate composition may occur in response to local and global changes in temperature, carbonate saturation state, and nutrient availability. Recurring upwelling along the west coast of the United States creates an alongshore mosaic of Ocean Acidification (OA), which may induce plastic responses and/or select for adaptive skeletal construction that can withstand pCO2 and temperature changes. Calcifying bryozoans provide a unique study system for investigating carbonate precipitation under variable conditions. Using a newly constructed flow-through CO2 control apparatus, we tested whether three laboratory-reared populations of the bryozoans Membranipora serrilamella, M. tuberculata and Celleporella cornuta showed differences in growth, calcification, and skeletal composition in response to simulated future OA conditions. Under elevated pCO2 (1200 μatm), bryozoans showed no significant differences in growth rate (new zooids added) compared to clones reared under current atmospheric values. However, C. cornuta colonies raised under high CO2 were significantly lighter, with less carbonate per zooid compared to colonies grown in present-day conditions (400 μatm). Scanning electron microscopy revealed that elevated pCO2 led to dissolution of bryozoan skeletons, which did not occur at 400 μatm. Structural changes in M. tuberculata and C. cornuta colonies may be related to the dissolution of high magnesium calcite skeletal components. Analyses of bryozoan morphological responses along with environmental proxies (δ13C, δ18O, and Mg/Ca ratios) could yield high resolution records of temperature and pH, which could be used to help reconstruct environmental variation along the California coast.

Plasticity in skeletal characteristics of nursery-raised staghorn coral, Acropora cervicornis

Science.gov (United States)

Kuffner, Ilsa B.; Bartels, Erich; Stathakopoulos, Anastasios; Enochs, Ian C.; Kolodziej, Graham; Toth, Lauren; Manzello, Derek P.

2017-01-01

Staghorn coral, Acropora cervicornis, is a threatened species and the primary focus of western Atlantic reef restoration efforts to date. We compared linear extension, calcification rate, and skeletal density of nursery-raised A. cervicornis branches reared for 6 months either on blocks attached to substratum or hanging from PVC trees in the water column. We demonstrate that branches grown on the substratum had significantly higher skeletal density, measured using computerized tomography, and lower linear extension rates compared to water-column fragments. Calcification rates determined with buoyant weighing were not statistically different between the two grow-out methods, but did vary among coral genotypes. Whereas skeletal density and extension rates were plastic traits that depended on grow-out method, calcification rate was conserved. Our results show that the two rearing methods generate the same amount of calcium carbonate skeleton but produce colonies with different skeletal characteristics and suggest that there is genetically based variability in coral calcification performance.

Plasticity in skeletal characteristics of nursery-raised staghorn coral, Acropora cervicornis

Science.gov (United States)

Kuffner, Ilsa B.; Bartels, Erich; Stathakopoulos, Anastasios; Enochs, Ian C.; Kolodziej, G.; Toth, Lauren T.; Manzello, Derek P.

2017-09-01

Staghorn coral, Acropora cervicornis, is a threatened species and the primary focus of western Atlantic reef restoration efforts to date. We compared linear extension, calcification rate, and skeletal density of nursery-raised A. cervicornis branches reared for 6 months either on blocks attached to substratum or hanging from PVC trees in the water column. We demonstrate that branches grown on the substratum had significantly higher skeletal density, measured using computerized tomography, and lower linear extension rates compared to water-column fragments. Calcification rates determined with buoyant weighing were not statistically different between the two grow-out methods, but did vary among coral genotypes. Whereas skeletal density and extension rates were plastic traits that depended on grow-out method, calcification rate was conserved. Our results show that the two rearing methods generate the same amount of calcium carbonate skeleton but produce colonies with different skeletal characteristics and suggest that there is genetically based variability in coral calcification performance.

Investigating Interactions between the Silica and Carbon Cycles during Precipitation and Early Diagenesis of Authigenic Clay/Carbonate-Mineral Associations in the Carbonate Rock Record

Science.gov (United States)

McKenzie, J. A.; Francisca Martinez Ruiz, F.; Sanchez-Roman, M.; Anjos, S.; Bontognali, T. R. R.; Nascimento, G. S.; Vasconcelos, C.

2017-12-01

The study of authigenic clay/carbonate-mineral associations within carbonate sequences has important implications for the interpretation of scientific problems related with rock reservoir properties, such as alteration of potential porosity and permeability. More specifically, when clay minerals are randomly distributed within the carbonate matrix, it becomes difficult to predict reservoir characteristics. In order to understand this mineral association in the geological record, we have undertaken a comparative study of specially designed laboratory experiments with modern environments, where clay minerals have been shown to precipitate together with a range of carbonate minerals, including calcite, Mg-calcite and dolomite. Two modern dolomite-forming environments, the Coorong lakes, South Australia and Brejo do Espinho Rio de Janeiro, Brazil, were selected for this investigation. For comparative evaluation, enrichment microbial culture experiments, using natural pore water from Brejo do Espinho as the growth medium to promote mineral precipitation, were performed under both aerobic and anaerobic conditions. To establish the environmental parameters and biological processes facilitating the dual mineral association, the experimental samples have been compared with the natural minerals using HRTEM measurements. The results demonstrate that the clay and carbonate minerals apparently do not co-precipitate, but the precipitation of the different minerals in the same sample has probably occurred under different environmental conditions with variable chemistries, e.g., hypersalinity versus normal salinity resulting from the changing ratio of evaporation versus precipitation. Thus, the investigated mineral association is not a product of diagenetic processes but of sequential in situ precipitation processes related to changes in the silica and carbon availability. Implications for ancient carbonate formations will be presented and discussed in the context of a specific

Quantitative skeletal scintiscanning

International Nuclear Information System (INIS)

Haushofer, R.

1982-01-01

330 patients were examined by skeletal scintiscanning with sup(99m)Tc pyrophosphate and sup(99m)methylene diphosphonate in the years between 1977 and 1979. Course control examinations were carried out in 12 patients. The collective of patients presented with primary skeletal tumours, metastases, inflammatory and degenerative skeletal diseases. Bone scintiscanning combined with the ''region of interest'' technique was found to be an objective and reproducible technique for quantitative measurement of skeletal radioactivity concentrations. The validity of nuclear skeletal examinations can thus be enhanced as far as diagnosis, course control, and differential diagnosis are concerned. Quantitative skeletal scintiscanning by means of the ''region of interest'' technique has opened up a new era in skeletal diagnosis by nuclear methods. (orig./MG) [de

Carbonate-platform response to the Toarcian Oceanic Anoxic Event in the southern hemisphere: Implications for climatic change and biotic platform demise

Science.gov (United States)

Han, Zhong; Hu, Xiumian; Kemp, David B.; Li, Juan

2018-05-01

The Toarcian Oceanic Anoxic Event (T-OAE, ∼183 Ma) was a profound short-term environmental perturbation associated with the large-scale release of 13C-depleted carbon into the global ocean-atmosphere system, which resulted in a significant negative carbon-isotope excursion (CIE). The general lack of characteristic T-OAE records outside of the northern hemisphere means that the precise environmental effects and significance of this event are uncertain. Many biotic carbonate platforms of the northern hemisphere western Tethys drowned or shifted to non-skeletal platforms during the early Toarcian. However, southern hemisphere records of Toarcian carbonate platforms are rare, and thus the extent and significance of biotic platform demise during the T-OAE is unclear. Here we present high-resolution geochemical and sedimentological data across two Pliensbachian-Toarcian shallow-water carbonate-platform sections exposed in the Tibetan Himalaya. These sections were located paleogeographically on the open southeastern tropical Tethyan margin in the southern hemisphere. The T-OAE in the Tibetan Himalaya is marked by a negative CIE in organic matter. Our sedimentological analysis of the two sections reveals an abundance of storm deposits within the T-OAE interval, which emphasizes a close link between warming and tropical storms during the T-OAE event, in line with evidence recently provided from western Tethyan sections of the northern hemisphere. In addition, our analysis also reveals extensive biotic carbonate-platform demise by drowning or changing to non-skeletal carbonates coincident with the onset of the CIE. Taken together, our results suggest that rapid and pervasive seawater warming in response to carbon release likely played a significant role in sudden biotic carbonate platform demise, and suppression/postponement of biotic platform re-development along the whole tropical/subtropical Tethyan margin.

Late Glacial Tropical Savannas in Sundaland Inferred From Stable Carbon Isotope Records of Cave Guano

Science.gov (United States)

Wurster, C. M.; Bird, M. I.; Bull, I.; Dungait, J.; Bryant, C. L.; Ertunç, T.; Hunt, C.; Lewis, H. A.; Paz, V.

2008-12-01

During the Last Glacial Period (LGP), reduced global sea level exposed the continental shelf south of Thailand to Sumatra, Java, and Borneo to form the contiguous continent of Sundaland. However, the type and extent of vegetation that existed on much of this exposed landmass during the LGP remains speculative. Extensive bird and bat guano deposits in caves throughout this region span beyond 40,000 yr BP, and contain a wealth of untapped stratigraphic palaeoenvironmental information. Stable carbon isotope ratios of insectivorous bird and bat guano contain a reliable record of the animal's diet and, through non-specific insect predation, reflect the relative abundance of major physiological pathways in plants. Various physiological pathways of carbon fixation in plants yield differing stable carbon isotope ratios. Stable carbon isotope values of C3 plants are lower than C4 vegetation due to different enzymatic discriminations of the heavy isotope through the carbon fixing pathways. In tropical locales, grasses nearly always follow the C4 photosynthetic pathway, whereas tropical rainforest uses C3 photosynthesis, providing a proxy for vegetation and therefore climate change in the past. Here we discuss four guano stable-isotope records, based on insect cuticle and n-alkane analysis, supplemented by pollen analysis. All sites suggest a C3 dominated ecosystem for the Holocene, consistent with the wet tropical forest vegetation present at all locations. Two sites from Palawan Island, Philippines, record stable carbon isotope values of guano that document a drastic change from C3 (forest) to C4 (savanna) dominated ecosystems during the Last Glacial Maximum (LGM). A third location, at Niah Great Cave, Malaysia, indicates C3-dominant vegetation throughout the record, but does display variation in stable carbon isotope values likely linked to humidity changes. A fourth location, Batu Caves in Peninsular Malaysia, also indicates open vegetation during the LGM. Vegetation

Interactive effects of temperature, food and skeletal mineralogy mediate biological responses to ocean acidification in a widely distributed bryozoan.

Science.gov (United States)

Swezey, Daniel S; Bean, Jessica R; Ninokawa, Aaron T; Hill, Tessa M; Gaylord, Brian; Sanford, Eric

2017-04-26

Marine invertebrates with skeletons made of high-magnesium calcite may be especially susceptible to ocean acidification (OA) due to the elevated solubility of this form of calcium carbonate. However, skeletal composition can vary plastically within some species, and it is largely unknown how concurrent changes in multiple oceanographic parameters will interact to affect skeletal mineralogy, growth and vulnerability to future OA. We explored these interactive effects by culturing genetic clones of the bryozoan Jellyella tuberculata (formerly Membranipora tuberculata ) under factorial combinations of dissolved carbon dioxide (CO 2 ), temperature and food concentrations. High CO 2 and cold temperature induced degeneration of zooids in colonies. However, colonies still maintained high growth efficiencies under these adverse conditions, indicating a compensatory trade-off whereby colonies degenerate more zooids under stress, redirecting energy to the growth and maintenance of new zooids. Low-food concentration and elevated temperatures also had interactive effects on skeletal mineralogy, resulting in skeletal calcite with higher concentrations of magnesium, which readily dissolved under high CO 2 For taxa that weakly regulate skeletal magnesium concentration, skeletal dissolution may be a more widespread phenomenon than is currently documented and is a growing concern as oceans continue to warm and acidify. © 2017 The Author(s).

Induced skeletal mutations

International Nuclear Information System (INIS)

Selby, P.B.

1979-01-01

This paper describes a large-scale experiment that, by means of breeding tests, confirmed that many dominant skeletal mutations are induced by large-dose radiation exposure. The author also discusses: (1) the major advantages and disadvantages of the skeletal method in improving estimates of genetic hazard to man; (2) future uses of the skeletal method; (3) direct estimation of risk beyond the first generation using the skeletal method; and (4) the possibility of using the skeletal method as a quick and easy screen for chemical mutagens

Paired carbon stable-isotope records for the Cenomanian Stage (100.5 -93.9 Ma): correlation tool and Late Cretaceous pCO2 record?

Science.gov (United States)

Jarvis, Ian; Gröcke, Darren; Laurin, Jiří; Selby, David; Roest-Ellis, Sascha; Miles, Andrew; Lignum, John; Gale, Andrew; Kennedy, Jim

2016-04-01

Carbon stable-isotope stratigraphy of marine carbonates (δ13Ccarb) provides remarkable insights into past variation in the global carbon cycle, and has become firmly established as a powerful global correlation tool. Continuous δ13Ccarb time series are becoming increasingly available for much of the geological record, including the Upper Cretaceous. However, our knowledge of stratigraphic variation in the carbon isotopic composition of sedimentary organic matter (δ13Corg) is much poorer, and is generally restricted to organic-rich sedimentary successions and/or key boundary intervals. Close coupling exists between the global isotopic composition of the reduced and oxidised carbon reservoirs on geological time scales, but the stratigraphic resolution of most long-term δ13Corg Mesozoic records is inadequate to identify leads and lags in the responses of the two reservoirs to carbon cycle perturbations. Cenomanian times (100.5-93.9 Ma) represent perhaps the best documented episode of eustatic rise in sea level in Earth history and the beginning of the Late Mesozoic thermal maximum, driving global expansion of epicontinental seas and the onset of widespread pelagic and hemipelagic carbonate deposition. Significant changes occurred in global stable-isotope records, including two prominent perturbations of the carbon cycle - the Mid-Cenomanian Event I (MCEI; ~96.5-96.2 Ma) and Oceanic Anoxic Event 2 (OAE2; ~94.5-93.8 Ma). OAE2, one of two truly global Cretaceous OAEs, was marked by the widespread deposition of black shales, and a global positive carbon stable-isotope excursion of 2.0 - 2.5‰ δ13Ccarb, and up to 7‰ in the sulphur-bound phytane biomarker. MCEI, by contrast, shows a English Chalk reference section at Folkestone, and correlate the carbon-isotope events between England, France, Germany and Italy. Comparison of the Vergons δ13Ccarb vs. δ13Corg profiles demonstrates similar medium-term stratigraphic variation, but significant differences in both short

A Real-Time Recording Model of Key Indicators for Energy Consumption and Carbon Emissions of Sustainable Buildings

Directory of Open Access Journals (Sweden)

Weiwei Wu

2014-05-01

Full Text Available Buildings’ sustainability is one of the crucial parts for achieving urban sustainability. Applied to buildings, life-cycle assessment encompasses the analysis and assessment of the environmental effects of building materials, components and assemblies throughout the entire life of the building construction, use and demolition. Estimate of carbon emissions is essential and crucial for an accurate and reasonable life-cycle assessment. Addressing the need for more research into integrating analysis of real-time and automatic recording of key indicators for a more accurate calculation and comparison, this paper aims to design a real-time recording model of these crucial indicators concerning the calculation and estimation of energy use and carbon emissions of buildings based on a Radio Frequency Identification (RFID-based system. The architecture of the RFID-based carbon emission recording/tracking system, which contains four functional layers including data record layer, data collection/update layer, data aggregation layer and data sharing/backup layer, is presented. Each of these layers is formed by RFID or network devices and sub-systems that operate at a specific level. In the end, a proof-of-concept system is developed to illustrate the implementation of the proposed architecture and demonstrate the feasibility of the design. This study would provide the technical solution for real-time recording system of building carbon emissions and thus is of great significance and importance to improve urban sustainability.

A Real-Time Recording Model of Key Indicators for Energy Consumption and Carbon Emissions of Sustainable Buildings

Science.gov (United States)

Wu, Weiwei; Yang, Huanjia; Chew, David; Hou, Yanhong; Li, Qiming

2014-01-01

Buildings' sustainability is one of the crucial parts for achieving urban sustainability. Applied to buildings, life-cycle assessment encompasses the analysis and assessment of the environmental effects of building materials, components and assemblies throughout the entire life of the building construction, use and demolition. Estimate of carbon emissions is essential and crucial for an accurate and reasonable life-cycle assessment. Addressing the need for more research into integrating analysis of real-time and automatic recording of key indicators for a more accurate calculation and comparison, this paper aims to design a real-time recording model of these crucial indicators concerning the calculation and estimation of energy use and carbon emissions of buildings based on a Radio Frequency Identification (RFID)-based system. The architecture of the RFID-based carbon emission recording/tracking system, which contains four functional layers including data record layer, data collection/update layer, data aggregation layer and data sharing/backup layer, is presented. Each of these layers is formed by RFID or network devices and sub-systems that operate at a specific level. In the end, a proof-of-concept system is developed to illustrate the implementation of the proposed architecture and demonstrate the feasibility of the design. This study would provide the technical solution for real-time recording system of building carbon emissions and thus is of great significance and importance to improve urban sustainability. PMID:24831109

Carbon isotopic record from Upper Devonian carbonates at Dongcun in Guilin, southern China, supporting the world-wide pattern of carbon isotope excursions during Frasnian-Famennian transition

Institute of Scientific and Technical Information of China (English)

无

2003-01-01

Two positive δ13C excursions are presented in records from the Frasnian-Famennian (F-F) marine carbonate sediments in Europe, America, Africa, and Australia, having been considered as a worldwide pattern, and attributed to enhanced organic carbon burial during the F-F biological mass extinction. However, this worldwide pattern has not been revealed from the well-deposited Late Devonian sequences in southern China. In this paper, a detailed investigation has been made on the Late Devonian section at Dongcun, Guilin, southern China to constrain perturbations in δ13C of carbonates in the F-F deposited sequence. The result from this section also indicates two positive δ13C excursions during the F-F transition. The first excursion with an amplitude of 1.5‰ occurred at the bottom of linguiformis Zone, later than the early excursion existing in the Late rhenana Zone of the Late Devonian profiles in other continents, especially, in central Europe. This difference has been expected to be a result as conodont Palmatolepis linguiformis occurred earlier in southern China than other sites. The second excursion with an amplitude of 2.1‰ is located at the F-F boundary, same as the records from other continents. This result strongly supports the view that two carbon isotope positive excursions during the F-F transition are common in carbonate sediments, resulting from worldwide increases of organic carbon burial intensity.

Record annual increase of carbon dioxide observed at Mauna Loa for 2015 |

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Climate Oceans & Coasts Fisheries Satellites Research Marine & Aviation Charting Sanctuaries Research Record annual increase of carbon dioxide observed at Mauna Loa for 2015 Climate Research Share Niño weather pattern, as forests, plantlife and other terrestrial systems responded to changes in

Insertion of linear 8.4 μm diameter 16 channel carbon fiber electrode arrays for single unit recordings

Science.gov (United States)

Patel, Paras R.; Na, Kyounghwan; Zhang, Huanan; Kozai, Takashi D. Y.; Kotov, Nicholas A.; Yoon, Euisik; Chestek, Cynthia A.

2016-01-01

Objective Single carbon fiber electrodes (d=8.4 μm) insulated with parylene-c and functionalized with PEDOT:pTS have been shown to record single unit activity but manual implantation of these devices with forceps can be difficult. Without an improvement in the insertion method any increase in the channel count by fabricating carbon fiber arrays would be impractical. In this study, we utilize a water soluble coating and structural backbones that allow us to create, implant, and record from fully functionalized arrays of carbon fibers with ~150 μm pitch. Approach Two approaches were tested for the insertion of carbon fiber arrays. The first method used a PEG coating that temporarily stiffened the fibers while leaving a small portion at the tip exposed. The small exposed portion (500 μm – 1 mm) readily penetrated the brain allowing for an insertion that did not require the handling of each fiber by forceps. The second method involved the fabrication of silicon support structures with individual shanks spaced 150 μm apart. Each shank consisted of a small groove that held an individual carbon fiber. Main results Our results showed that the PEG coating allowed for the chronic implantation of carbon fiber arrays in 5 rats with unit activity detected at 31 days post-implant. The silicon support structures recorded single unit activity in 3 acute rat surgeries. In one of those surgeries a stacked device with 3 layers of silicon support structures and carbon fibers was built and shown to readily insert into the brain with unit activity on select sites. Significance From these studies we have found that carbon fibers spaced at ~150 μm readily insert into the brain. This greatly increases the recording density of chronic neural probes and paves the way for even higher density devices that have a minimal scarring response. PMID:26035638

Century-scale high-resolution black carbon records in sediment cores from the South Yellow Sea, China

Science.gov (United States)

Xu, Xiaoming; Hong, Yuehui; Zhou, Qianzhi; Liu, Jinzhong; Yuan, Lirong; Wang, Jianghai

2018-01-01

Black carbon (BC) has received increasing attention in the last 20 years because it is not only an absorbent of toxic pollutants but also a greenhouse substance, preserving fire-history records, and more importantly, acting as an indicator of biogeochemical cycles and global changes. By adopting an improved chemothermal oxidation method (WXY), this study reconstructed the century-scale high-resolution records of BC deposition from two fine-grained sediment cores collected from the Yellow Sea Cold Water Mass in the South Yellow Sea. The BC records were divided into five stages, which exhibited specific sequences with three BC peaks at approximately 1891, 1921, and 2007 AD, representing times at which the first heavy storms appeared just after the termination of long-term droughts. The significant correlation between the times of the BC peaks in the cores and heavy storms in the area of the Huanghe (Yellow) River demonstrated that BC peaks could result from markedly strengthened sedimentation due to surface runoff, which augmented the atmospheric deposition. Stable carbon isotope analysis indicated that the evident increase in carbon isotope ratios of BC in Stage 5 might have resulted from the input of weathered rock-derived graphitic carbon cardinally induced by the annual anthropogenic modulation of water-borne sediment in the Huanghe River since 2005 AD. Numerical calculations demonstrated that the input fraction of graphitic carbon was 22.97% for Stage 5, whereas no graphitic carbon entered during Stages 1 and 3. The obtained data provide new and important understanding of the source-sink history of BC in the Yellow Sea.

The yield of high-detail radiographic skeletal surveys in suspected infant abuse

International Nuclear Information System (INIS)

Barber, Ignasi; Perez-Rossello, Jeannette M.; Kleinman, Paul K.; Wilson, Celeste R.

2015-01-01

Skeletal surveys are routinely performed in cases of suspected child abuse, but there are limited data regarding the yield of high-detail skeletal surveys in infants. To determine the diagnostic yield of high-detail radiographic skeletal surveys in suspected infant abuse. We reviewed the high-detail American College of Radiology standardized skeletal surveys performed for suspected abuse in 567 infants (median: 4.4 months, SD 3.47; range: 4 days-12 months) at a large urban children's hospital between 2005 and 2013. Skeletal survey images, radiology reports and medical records were reviewed. A skeletal survey was considered positive when it showed at least one unsuspected fracture. In 313 of 567 infants (55%), 1,029 definite fractures were found. Twenty-one percent (119/567) of the patients had a positive skeletal survey with a total of 789 (77%) unsuspected fractures. Long-bone fractures were the most common injuries, present in 145 children (26%). The skull was the site of fracture in 138 infants (24%); rib cage in 77 (14%), clavicle in 24 (4.2%) and uncommon fractures (including spine, scapula, hands and feet and pelvis) were noted in 26 infants (4.6%). Of the 425 infants with neuroimaging, 154 (36%) had intracranial injury. No significant correlation between positive skeletal survey and associated intracranial injury was found. Scapular fractures and complex skull fractures showed a statistically significant correlation with intracranial injury (P = 0.029, P = 0.007, respectively). Previously unsuspected fractures are noted on skeletal surveys in 20% of cases of suspected infant abuse. These data may be helpful in the design and optimization of global skeletal imaging in this vulnerable population. (orig.)

The yield of high-detail radiographic skeletal surveys in suspected infant abuse

Energy Technology Data Exchange (ETDEWEB)

Barber, Ignasi [Hospital Vall d' Hebron, Universitat Autonoma de Barcelona, Pediatric Radiology Department, Barcelona (Spain); Perez-Rossello, Jeannette M.; Kleinman, Paul K. [Boston Children' s Hospital, Radiology Department, Boston, MA (United States); Wilson, Celeste R. [Boston Children' s Hospital, Division of General Pediatrics, Boston, MA (United States)

2014-07-06

Skeletal surveys are routinely performed in cases of suspected child abuse, but there are limited data regarding the yield of high-detail skeletal surveys in infants. To determine the diagnostic yield of high-detail radiographic skeletal surveys in suspected infant abuse. We reviewed the high-detail American College of Radiology standardized skeletal surveys performed for suspected abuse in 567 infants (median: 4.4 months, SD 3.47; range: 4 days-12 months) at a large urban children's hospital between 2005 and 2013. Skeletal survey images, radiology reports and medical records were reviewed. A skeletal survey was considered positive when it showed at least one unsuspected fracture. In 313 of 567 infants (55%), 1,029 definite fractures were found. Twenty-one percent (119/567) of the patients had a positive skeletal survey with a total of 789 (77%) unsuspected fractures. Long-bone fractures were the most common injuries, present in 145 children (26%). The skull was the site of fracture in 138 infants (24%); rib cage in 77 (14%), clavicle in 24 (4.2%) and uncommon fractures (including spine, scapula, hands and feet and pelvis) were noted in 26 infants (4.6%). Of the 425 infants with neuroimaging, 154 (36%) had intracranial injury. No significant correlation between positive skeletal survey and associated intracranial injury was found. Scapular fractures and complex skull fractures showed a statistically significant correlation with intracranial injury (P = 0.029, P = 0.007, respectively). Previously unsuspected fractures are noted on skeletal surveys in 20% of cases of suspected infant abuse. These data may be helpful in the design and optimization of global skeletal imaging in this vulnerable population. (orig.)

Carbon and nitrogen isotope variations in tree-rings as records of perturbations in regional carbon and nitrogen cycles.

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Bukata, Andrew R; Kyser, T Kurtis

2007-02-15

Increasing anthropogenic pollution from urban centers and fossil fuel combustion can impact the carbon and nitrogen cycles in forests. To assess the impact of twentieth century anthropogenic pollution on forested system carbon and nitrogen cycles, variations in the carbon and nitrogen isotopic compositions of tree-rings were measured. Individual annual growth rings in trees from six sites across Ontario and one in New Brunswick, Canada were used to develop site chronologies of tree-ring delta 15N and delta 13C values. Tree-ring 615N values were approximately 0.5% per hundred higher and correlated with contemporaneous foliar samples from the same tree, but not with delta 15N values of soil samples. Temporal trends in carbon and nitrogen isotopic compositions of these tree-rings are consistent with increasing anthropogenic influence on both the carbon and nitrogen cycles since 1945. Tree-ring delta 13C values and delta 15N values are correlated at both remote and urban-proximal sites, with delta 15N values decreasing since 1945 and converging on 1% per hundred at urban-proximal sites and decreasing but not converging on a single delta 15N value in remote sites. These results indicate that temporal trends in tree-ring nitrogen and carbon isotopic compositions record the regional extent of pollution.

Early orthodontic treatment of skeletal open-bite malocclusion with the open-bite bionator: a cephalometric study.

Science.gov (United States)

Defraia, Efisio; Marinelli, Andrea; Baroni, Giulia; Franchi, Lorenzo; Baccetti, Tiziano

2007-11-01

This study was designed to evaluate the effectiveness of the open-bite bionator in growing subjects with increased vertical dimensions. The records of 20 subjects with high-angle skeletal relationships (MPA > or =25 degrees) were examined. Cephalometric measurements were compared with those obtained from 23 sets of records of an untreated group matched according to age, sex, vertical skeletal relationships, and time intervals between records. Lateral cephalograms were analyzed before the start of treatment (mean age; 8.3 years) and after therapy and retention, with a mean period of observation of 2.5 years. The treated group had a significantly smaller palatal plane-mandibular plane angle (-1.9 degrees) and a greater overbite (+1.5 mm) associated with a significantly smaller overjet when compared with the control group. Based on the analysis of this sample, early treatment of skeletal open bite with the open-bite bionator appears to produce a modest effect that mainly consists of significant improvement in intermaxillary divergence. No favorable effects on the extrusion of posterior teeth were found.

The Difference in Cervical Vertebral Skeletal Maturation between Cleft Lip/Palate and Non-Cleft Lip/Palate Orthodontic Patients.

Science.gov (United States)

Batwa, Waeil; Almoammar, Khalid; Aljohar, Aziza; Alhussein, Abdullah; Almujel, Saad; Zawawi, Khalid H

2018-01-01

The aim was to evaluate differences in the cervical vertebral skeletal maturity of unilateral cleft lip and palate (UCLP) and non-cleft lip/palate (non-CLP) Saudi male orthodontic patients. This cross-sectional multicenter study took place at the dental school, King Saud University and King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia, between October 2014 and September 2015. The records of Saudi male orthodontic patients with UCLP ( n = 69) were collected. Cervical vertebral maturation was assessed using their cephalometric radiographs. The records of 138 age-matched non-CLP Saudi male orthodontic patients served as controls. There was a significant difference in skeletal maturity between the UCLP and non-CLP groups, as evident in the delayed skeletal development among the UCLP participants. Moreover, pubertal growth spurt onset was significantly earlier in the non-cleft participants in comparison with the UCLP participants ( p = 0.009). There is delayed skeletal maturity among the UCLP Saudi male population in comparison with their non-CLP age-matched peers.

Deep bite malocclusion: exploration of the skeletal and dental factors

International Nuclear Information System (INIS)

Bhateja, N.K.; Fida, M.; Shaikh, A.

2016-01-01

Correction of deep bite is crucial for maintenance of dental hard and soft tissue structures and for prevention of temporomandibular joint disorders. Exploration of underlying skeletal and dental factors is essential for efficient and individualized treatment planning. To date etiological factors of dental and skeletal deep bite have not been explored in Pakistani orthodontic patients. The objectives of this study were to explore frequencies of dental and skeletal etiological factors in deep bite patients and to determine correlations amongst dental and skeletal etiological factors of deep bite. Methods: The study included a total of 113 subjects (males=35; females=78) with no craniofacial syndromes or prior orthodontic treatment. Pre-treatment orthodontic records were used to evaluate various dental and skeletal parameters. Descriptive statistics of each parameter were calculated. The various study parameters were correlated using Pearson's Correlation. Results: Deep curve of Spee was most frequently seen factor of dental deep bite (72.6%), followed by increased coronal length of upper incisors (28.3%), retroclined upper incisors (17.7%), retroclined lower incisors (8%) and increased coronal length of lower incisors (5.3%). Decreased gonial angle was most commonly found factor of skeletal deep bite (43.4%), followed by decreased mandibular plane angle (27.4%) and maxillary plane's clockwise rotation (26.5%). Frankfort mandibular plane angle and gonial angle showed a strong positive correlation (r=0.66, p=0.000). Conclusions: Reduced gonial angle is most frequently seen skeletal factor, signifying the importance of angulation and growth of ramus in development of deep bite. Deep curve of Spee is most frequently seen dental etiological component in deep bite subjects, hence signifying the importance of intruding the lower anterior teeth. (author)

Silicon nitride gradient film as the underlayer of ultra-thin tetrahedral amorphous carbon overcoat for magnetic recording slider

Energy Technology Data Exchange (ETDEWEB)

Wang Guigen, E-mail: wanggghit@yahoo.com [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China); Kuang Xuping; Zhang Huayu; Zhu Can [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China); Han Jiecai [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China); Center for Composite Materials, Harbin Institute of Technology, Harbin 150080 (China); Zuo Hongbo [Center for Composite Materials, Harbin Institute of Technology, Harbin 150080 (China); Ma Hongtao [SAE Technologies Development (Dongguan) Co., Ltd., Dongguan 523087 (China)

2011-12-15

Highlights: Black-Right-Pointing-Pointer The ultra-thin carbon films with different silicon nitride (Si-N) film underlayers were prepared. Black-Right-Pointing-Pointer It highlighted the influences of Si-N underlayers. Black-Right-Pointing-Pointer The carbon films with Si-N underlayers obtained by nitriding especially at the substrate bias of -150 V, can exhibit better corrosion protection properties - Abstract: There are higher technical requirements for protection overcoat of magnetic recording slider used in high-density storage fields for the future. In this study, silicon nitride (Si-N) composition-gradient films were firstly prepared by nitriding of silicon thin films pre-sputtered on silicon wafers and magnetic recording sliders, using microwave electron cyclotron resonance plasma source. The ultra-thin tetrahedral amorphous carbon films were then deposited on the Si-N films by filtered cathodic vacuum arc method. Compared with amorphous carbon overcoats with conventional silicon underlayers, the overcoats with Si-N underlayers obtained by plasma nitriding especially at the substrate bias of -150 V, can provide better corrosion protection for high-density magnetic recording sliders.

Silicon nitride gradient film as the underlayer of ultra-thin tetrahedral amorphous carbon overcoat for magnetic recording slider

International Nuclear Information System (INIS)

Wang Guigen; Kuang Xuping; Zhang Huayu; Zhu Can; Han Jiecai; Zuo Hongbo; Ma Hongtao

2011-01-01

Highlights: ► The ultra-thin carbon films with different silicon nitride (Si-N) film underlayers were prepared. ► It highlighted the influences of Si-N underlayers. ► The carbon films with Si-N underlayers obtained by nitriding especially at the substrate bias of −150 V, can exhibit better corrosion protection properties - Abstract: There are higher technical requirements for protection overcoat of magnetic recording slider used in high-density storage fields for the future. In this study, silicon nitride (Si-N) composition-gradient films were firstly prepared by nitriding of silicon thin films pre-sputtered on silicon wafers and magnetic recording sliders, using microwave electron cyclotron resonance plasma source. The ultra-thin tetrahedral amorphous carbon films were then deposited on the Si-N films by filtered cathodic vacuum arc method. Compared with amorphous carbon overcoats with conventional silicon underlayers, the overcoats with Si-N underlayers obtained by plasma nitriding especially at the substrate bias of −150 V, can provide better corrosion protection for high-density magnetic recording sliders.

Constraining the cause of the end-Guadalupian extinction with coupled records of carbon and calcium isotopes

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Jost, A. B.; Mundil, R.; He, B.; Brown, S. T.; Altiner, D.; Sun, Y.; DePaolo, D. J.; Payne, J.

2013-12-01

A negative δ13C excursion in carbonate sediments from Guadalupian (Middle Permian) and Lopingian (Late Permian) stratigraphic sections has been interpreted to result from a large carbon cycle disturbance during end-Guadalupian extinction event (ca. 260 Ma). However, the carbon isotope data alone are insufficient to uniquely determine the type and magnitude of perturbations to the global carbon cycle. The carbon and calcium cycles are coupled via CaCO3 burial, so changes in calcium isotopes can be used to constrain the cause of a carbon isotope excursion. In this study, we present coupled carbon and calcium isotope records from three Guadalupian-Lopingian (G/L) sections in China and Turkey. Isotope records among our studied sections are inconsistent in both their δ13C and δ44/40Ca records. Similar inconsistencies in δ13C among sections occur across previously published datasets. Sections with large (>3‰) changes in δ13C either show evidence for diagenetic alteration or do not show δ13C and δ44/40Ca changes consistent with severe volcanic degassing from Emeishan or methane clathrate destabilization. We conclude that the large isotopic changes are more likely the result of local burial conditions or diagenetic effects, rather than a large carbon cycle disturbance. Perturbations to the global carbon and calcium cycles appear to have been much smaller across the G/L transition than across the subsequent Permian-Triassic boundary. This finding is consistent with recent paleobiological data showing that the end-Guadalupian extinction was much less severe than previously believed, and was indistinguishable in magnitude from background intervals. However, selective extinction of marine animals with passive respiratory physiology indicates that the G/L extinction cannot simply be due to background extinction or sampling failure, and that it was triggered by some environmental event. Therefore, any environmental event must have been small enough to not generate large

Skeletal muscle tissue engineering: methods to form skeletal myotubes and their applications.

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Ostrovidov, Serge; Hosseini, Vahid; Ahadian, Samad; Fujie, Toshinori; Parthiban, Selvakumar Prakash; Ramalingam, Murugan; Bae, Hojae; Kaji, Hirokazu; Khademhosseini, Ali

2014-10-01

Skeletal muscle tissue engineering (SMTE) aims to repair or regenerate defective skeletal muscle tissue lost by traumatic injury, tumor ablation, or muscular disease. However, two decades after the introduction of SMTE, the engineering of functional skeletal muscle in the laboratory still remains a great challenge, and numerous techniques for growing functional muscle tissues are constantly being developed. This article reviews the recent findings regarding the methodology and various technical aspects of SMTE, including cell alignment and differentiation. We describe the structure and organization of muscle and discuss the methods for myoblast alignment cultured in vitro. To better understand muscle formation and to enhance the engineering of skeletal muscle, we also address the molecular basics of myogenesis and discuss different methods to induce myoblast differentiation into myotubes. We then provide an overview of different coculture systems involving skeletal muscle cells, and highlight major applications of engineered skeletal muscle tissues. Finally, potential challenges and future research directions for SMTE are outlined.

Contemporaneous trace and body fossils from a late Pleistocene Lakebed in Victoria, Australia, allow assessment of bias in the fossil record.

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Camens, Aaron Bruce; Carey, Stephen Paul

2013-01-01

The co-occurrence of vertebrate trace and body fossils within a single geological formation is rare and the probability of these parallel records being contemporaneous (i.e. on or near the same bedding plane) is extremely low. We report here a late Pleistocene locality from the Victorian Volcanic Plains in south-eastern Australia in which demonstrably contemporaneous, but independently accumulated vertebrate trace and body fossils occur. Bite marks from a variety of taxa are also present on the bones. This site provides a unique opportunity to examine the biases of these divergent fossil records (skeletal, footprints and bite marks) that sampled a single fauna. The skeletal record produced the most complete fauna, with the footprint record indicating a markedly different faunal composition with less diversity and the feeding traces suggesting the presence, amongst others, of a predator not represented by either the skeletal or footprint records. We found that the large extinct marsupial predator Thylacoleo was the only taxon apparently represented by all three records, suggesting that the behavioral characteristics of large carnivores may increase the likelihood of their presence being detected within a fossil fauna. In contrast, Diprotodon (the largest-ever marsupial) was represented only by trace fossils at this site and was absent from the site's skeletal record, despite its being a common and easily detected presence in late Pleistocene skeletal fossil faunas elsewhere in Australia. Small mammals absent from the footprint record for the site were represented by skeletal fossils and bite marks on bones.

Analysis of microstructures for Co/Pd multilayer perpendicular magnetic recording media with carbon underlayer

International Nuclear Information System (INIS)

Asahi, T.; Kuramochi, K.; Kawaji, J.; Onoue, T.; Osaka, T.; Saigo, M.

2001-01-01

The effect of amorphous carbon underlayer thickness on the microstructure of the Co/Pd multilayer perpendicular magnetic recording media was investigated. From the magnetic force microscopy observation in the AC-demagnetized state of the Co/Pd multilayer media, the magnetic cluster size was observed to effectively decrease with an increase in carbon underlayer thickness, where the higher coercivity and the higher S/N ratio of the Co/Pd multilayer media were obtained with the thicker underlayer. Furthermore, the distribution of [1 1 1] orientation of FCC-Pd became broader, and the grain size decreased with an increase in the carbon underlayer thickness. These effects caused the magnetic exchange decoupling of Co/Pd multilayer media. We suggested that the change of microstructure was directly related to the surface roughness of the amorphous carbon underlayer

Cytoskeleton, L-type Ca2+ and stretch activated channels in injured skeletal muscle

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Fabio Francini

2013-07-01

Full Text Available The extra-sarcomeric cytoskeleton (actin microfilaments and anchoring proteins is involved in maintaining the sarco-membrane stiffness and integrity and in turn the mechanical stability and function of the intra- and sub-sarcoplasmic proteins. Accordingly, it regulates Ca2+ entry through the L-type Ca2+ channels and the mechano-sensitivity of the stretch activated channels (SACs. Moreover, being intra-sarcomeric cytoskeleton bound to costameric proteins and other proteins of the sarcoplasma by intermediate filaments, as desmin, it integrates the properties of the sarcolemma with the skeletal muscle fibres contraction. The aim of this research was to compare the cytoskeleton, SACs and the ECC alterations in two different types of injured skeletal muscle fibres: by muscle denervation and mechanical overload (eccentric contraction. Experiments on denervation were made in isolated Soleus muscle of male Wistar rats; forced eccentric-contraction (EC injury was achieved in Extensor Digitorum Longus muscles of Swiss mice. The method employed conventional intracellular recording with microelectrodes inserted in a single fibre of an isolated skeletal muscle bundle. The state of cytoskeleton was evaluated by recording SAC currents and by evaluating the resting membrane potential (RMP value determined in current-clamp mode. The results demonstrated that in both injured skeletal muscle conditions the functionality of L-type Ca2+ current, ICa, was affected. In parallel, muscle fibres showed an increase of the resting membrane permeability and of the SAC current. These issues, together with a more depolarized RMP are an index of altered cytoskeleton. In conclusion, we found a symilar alteration of ICa, SAC and cytoskeleton in both injured skeletal muscle conditions.

Characteristics of Skeletal Musculature of Pheasants Hatched from Eggs of Different Eggshell Colour

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Dragan Zikic

2016-05-01

Full Text Available The aim of this paper was to examine morphodinamics of development of skeletal musculature of pheasants hatched from eggs of different eggshell colour. Four groups of pheasant eggs (dark brown, light brown, brown/green and blue/green were incubated. Samples of skeletal musculature of leg and breast were taken during the embryonic and neonatal period of development. From taken samples histological preparations were made. In pheasants hatched from blue/green eggs the smaller diameter of leg and breast muscle cells and the higher volume density of connective tissue in leg and breast muscles were recorded. It was concluded that pheasants hatched from blue/green eggs had the weakest development of skeletal musculature, which can be related to structural differences of eggshell of various colour.

Sedimentology of polar carbonate systems

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Frank, T. D.; James, N. P.

2013-12-01

The key attributes, processes, and products associated with carbonate accumulation and diagenesis at tropical and temperate latitudes are well known. Comparatively little work has concentrated on carbonate deposition at the coldest end of the depositional spectrum, the polar shelves. Such deposits are not abundant, but they have the potential to provide unique insights into paleoceanographic and paleoclimatic conditions in regions of the planet that are arguably the most sensitive to global change. We examined skeletal assemblages, facies, stratigraphy, petrography, geochemistry, and diagenesis of Quaternary deposits from the Ross Sea, Antarctica and Permian counterparts from Gondwana (now eastern Australia). These modern and ancient polar carbonate factories possess several unique characteristics that set them apart from better-known systems of the temperate and tropical latitudes. All production is biogenic and there are no significant calcareous phototrophs. Carbonate communities are not capable of building rigid frameworks, and thus their deposits are prone to winnowing and reworking by waves and bottom currents. The seawater, although frigid, is isothermal, and thus deep-water benthic communities can exist near the surface. Carbonate saturation, which is at or below solubility for both aragonite and high-Mg calcite, plays a key role in determining the dominant mineralogy of benthos as well as the preservation potential of skeletal debris. As many taxa precipitate low-Mg calcite in isotopic equilibrium, deposits have potential to provide geochemical proxy information for use in paleoceanographic and paleoclimatic reconstructions. More than any other type of carbonate system, the slow biogenic carbonate production and accumulation in cold waters is achieved firstly by arresting siliciclastic sedimentation and secondly by increasing nutrient availability. Thus, carbonate deposition may occur during the coldest of times, such as during glacial advance when

Exploring the Relationship between Skeletal Mass and Total Body Mass in Birds.

Science.gov (United States)

Martin-Silverstone, Elizabeth; Vincze, Orsolya; McCann, Ria; Jonsson, Carl H W; Palmer, Colin; Kaiser, Gary; Dyke, Gareth

2015-01-01

Total body mass (TBM) is known to be related to a number of different osteological features in vertebrates, including limb element measurements and total skeletal mass. The relationship between skeletal mass and TBM in birds has been suggested as a way of estimating the latter in cases where only the skeleton is known (e.g., fossils). This relationship has thus also been applied to other extinct vertebrates, including the non-avian pterosaurs, while other studies have used additional skeletal correlates found in modern birds to estimate TBM. However, most previous studies have used TBM compiled from the literature rather than from direct measurements, producing values from population averages rather than from individuals. Here, we report a new dataset of 487 extant birds encompassing 79 species that have skeletal mass and TBM recorded at the time of collection or preparation. We combine both historical and new data for analyses with phylogenetic control and find a similar and well-correlated relationship between skeletal mass and TBM. Thus, we confirm that TBM and skeletal mass are accurate proxies for estimating one another. We also look at other factors that may have an effect on avian body mass, including sex, ontogenetic stage, and flight mode. While data are well-correlated in all cases, phylogeny is a major control on TBM in birds strongly suggesting that this relationship is not appropriate for estimating the total mass of taxa outside of crown birds, Neornithes (e.g., non-avian dinosaurs, pterosaurs). Data also reveal large variability in both bird skeletal and TBM within single species; caution should thus be applied when using published mass to test direct correlations with skeletal mass and bone lengths.

Quantitative studies of skeletal muscle lactate metabolism

International Nuclear Information System (INIS)

Pagliassotti, M.J.

1988-01-01

In Situ, single-pass perfusions were employed on three isolated rabbit skeletal muscle preparations of differing fiber type and oxidative capacity to investigate the influence of fiber type and oxidative capacity per se on net carbon, 14 C-lactate, and 3 H-glucose fluxes. Preparations were exposed to six lactate concentrations ranging from 1-11mM. At basal lactate concentrations all preparations displayed net lactate release, 14 C-lactate removal and 14 CO 2 release, all were linearly correlated with lactate concentration. By 4mM all preparations switched to net lactate uptake and 14 C-lactate removal always exceeded net lactate uptake. To quantify the fate of net carbon, 14 C-lactate, and 3 H-glucose removal preparations were perfused at either basal or elevated lactate. Under basal conditions net carbon influx from glucose and glycogen was removed primarily via net lactate release in the glycolytic and mixed preparations and oxidation and net lactate release in the oxidative preparation. At elevated lactate, net carbon influx from lactate, pyruvate and glucose was removed primarily by net glycogen synthesis in the glycolytic preparation and both alanine release and oxidation in the mixed and oxidative preparations

The Difference in Cervical Vertebral Skeletal Maturation between Cleft Lip/Palate and Non-Cleft Lip/Palate Orthodontic Patients

Directory of Open Access Journals (Sweden)

Waeil Batwa

2018-01-01

Full Text Available Objective. The aim was to evaluate differences in the cervical vertebral skeletal maturity of unilateral cleft lip and palate (UCLP and non-cleft lip/palate (non-CLP Saudi male orthodontic patients. Method. This cross-sectional multicenter study took place at the dental school, King Saud University and King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia, between October 2014 and September 2015. The records of Saudi male orthodontic patients with UCLP n=69 were collected. Cervical vertebral maturation was assessed using their cephalometric radiographs. The records of 138 age-matched non-CLP Saudi male orthodontic patients served as controls. Results. There was a significant difference in skeletal maturity between the UCLP and non-CLP groups, as evident in the delayed skeletal development among the UCLP participants. Moreover, pubertal growth spurt onset was significantly earlier in the non-cleft participants in comparison with the UCLP participants p=0.009. Conclusions. There is delayed skeletal maturity among the UCLP Saudi male population in comparison with their non-CLP age-matched peers.

Diaphragmatic lymphatic vessel behavior during local skeletal muscle contraction.

Science.gov (United States)

Moriondo, Andrea; Solari, Eleonora; Marcozzi, Cristiana; Negrini, Daniela

2015-02-01

The mechanism through which the stresses developed in the diaphragmatic tissue during skeletal muscle contraction sustain local lymphatic function was studied in 10 deeply anesthetized, tracheotomized adult Wistar rats whose diaphragm was exposed after thoracotomy. To evaluate the direct effect of skeletal muscle contraction on the hydraulic intraluminal lymphatic pressures (Plymph) and lymphatic vessel geometry, the maximal contraction of diaphragmatic fibers adjacent to a lymphatic vessel was elicited by injection of 9.2 nl of 1 M KCl solution among diaphragmatic fibers while Plymph was recorded through micropuncture and vessel geometry via stereomicroscopy video recording. In lymphatics oriented perpendicularly to the longitudinal axis of muscle fibers and located at skeletal muscle contraction (Dmc) decreased to 61.3 ± 1.4% of the precontraction value [resting diameter (Drest)]; however, if injection was at >900 μm from the vessel, Dmc enlarged to 131.1 ± 2.3% of Drest. In vessels parallel to muscle fibers, Dmc increased to 122.8 ± 2.9% of Drest. During contraction, Plymph decreased as much as 22.5 ± 2.6 cmH2O in all submesothelial superficial vessels, whereas it increased by 10.7 ± 5.1 cmH2O in deeper vessels running perpendicular to contracting muscle fibers. Hence, the three-dimensional arrangement of the diaphragmatic lymphatic network seems to be finalized to efficiently exploit the stresses exerted by muscle fibers during the contracting inspiratory phase to promote lymph formation in superficial submesothelial lymphatics and its further propulsion in deeper intramuscular vessels. Copyright © 2015 the American Physiological Society.

40 CFR 60.1370 - What records must I keep for municipal waste combustion units that use activated carbon?

Science.gov (United States)

2010-07-01

... waste combustion unit at your plant. Include supporting calculations. (b) Records of low carbon feed... waste combustion units that use activated carbon? 60.1370 Section 60.1370 Protection of Environment... SOURCES Standards of Performance for Small Municipal Waste Combustion Units for Which Construction is...

Proteomics of Skeletal Muscle

DEFF Research Database (Denmark)

Deshmukh, Atul

2016-01-01

, of altered protein expressions profiles and/or their posttranslational modifications (PTMs). Mass spectrometry (MS)-based proteomics offer enormous promise for investigating the molecular mechanisms underlying skeletal muscle insulin resistance and exercise-induced adaptation; however, skeletal muscle......Skeletal muscle is the largest tissue in the human body and plays an important role in locomotion and whole body metabolism. It accounts for ~80% of insulin stimulated glucose disposal. Skeletal muscle insulin resistance, a primary feature of Type 2 diabetes, is caused by a decreased ability...... of muscle to respond to circulating insulin. Physical exercise improves insulin sensitivity and whole body metabolism and remains one of the most promising interventions for the prevention of Type 2 diabetes. Insulin resistance and exercise adaptations in skeletal muscle might be a cause, or consequence...

Hot spring microbial community composition, morphology, and carbon fixation: implications for interpreting the ancient rock record

Science.gov (United States)

Schuler, Caleb G.; Havig, Jeff R.; Hamilton, Trinity L.

2017-11-01

Microbial communities in hydrothermal systems exist in a range of macroscopic morphologies including stromatolites, mats, and filaments. The architects of these structures are typically autotrophic, serving as primary producers. Structures attributed to microbial life have been documented in the rock record dating back to the Archean including recent reports of microbially-related structures in terrestrial hot springs that date back as far as 3.5 Ga. Microbial structures exhibit a range of complexity from filaments to more complex mats and stromatolites and the complexity impacts preservation potential. As a result, interpretation of these structures in the rock record relies on isotopic signatures in combination with overall morphology and paleoenvironmental setting. However, the relationships between morphology, microbial community composition, and primary productivity remain poorly constrained. To begin to address this gap, we examined community composition and carbon fixation in filaments, mats, and stromatolites from the Greater Obsidian Pool Area (GOPA) of the Mud Volcano Area, Yellowstone National Park, WY. We targeted morphologies dominated by bacterial phototrophs located in close proximity within the same pool which are exposed to similar geochemistry as well as bacterial mat, algal filament and chemotrophic filaments from nearby springs. Our results indicate i) natural abundance δ13C values of biomass from these features (-11.0 to -24.3 ‰) are similar to those found in the rock record; ii) carbon uptake rates of photoautotrophic communities is greater than chemoautotrophic; iii) oxygenic photosynthesis, anoxygenic photosynthesis, and chemoautotrophy often contribute to carbon fixation within the same morphology; and iv) increasing phototrophic biofilm complexity corresponds to a significant decrease in rates of carbon fixation—filaments had the highest uptake rates whereas carbon fixation by stromatolites was significantly lower. Our data highlight

Hot Spring Microbial Community Composition, Morphology, and Carbon Fixation: Implications for Interpreting the Ancient Rock Record

Directory of Open Access Journals (Sweden)

Caleb G. Schuler

2017-11-01

Full Text Available Microbial communities in hydrothermal systems exist in a range of macroscopic morphologies including stromatolites, mats, and filaments. The architects of these structures are typically autotrophic, serving as primary producers. Structures attributed to microbial life have been documented in the rock record dating back to the Archean including recent reports of microbially-related structures in terrestrial hot springs that date back as far as 3.5 Ga. Microbial structures exhibit a range of complexity from filaments to more complex mats and stromatolites and the complexity impacts preservation potential. As a result, interpretation of these structures in the rock record relies on isotopic signatures in combination with overall morphology and paleoenvironmental setting. However, the relationships between morphology, microbial community composition, and primary productivity remain poorly constrained. To begin to address this gap, we examined community composition and carbon fixation in filaments, mats, and stromatolites from the Greater Obsidian Pool Area (GOPA of the Mud Volcano Area, Yellowstone National Park, WY. We targeted morphologies dominated by bacterial phototrophs located in close proximity within the same pool which are exposed to similar geochemistry as well as bacterial mat, algal filament and chemotrophic filaments from nearby springs. Our results indicate (i natural abundance δ13C values of biomass from these features (−11.0 to −24.3‰ are similar to those found in the rock record; (ii carbon uptake rates of photoautotrophic communities is greater than chemoautotrophic; (iii oxygenic photosynthesis, anoxygenic photosynthesis, and chemoautotrophy often contribute to carbon fixation within the same morphology; and (iv increasing phototrophic biofilm complexity corresponds to a significant decrease in rates of carbon fixation—filaments had the highest uptake rates whereas carbon fixation by stromatolites was significantly lower

Skeletal fluorosis in relation to drinking water in rural areas of West Azerbaijan, Iran.

Science.gov (United States)

Mohammadi, Ali Akbar; Yousefi, Mahmood; Yaseri, Mehdi; Jalilzadeh, Mohsen; Mahvi, Amir Hossein

2017-12-11

Skeletal fluorosis resulting from high fluoride level in drinking water is a major public health problem. The present study evaluated the association between exposures to drinking water fluoride and skeletal fluorosis in 5 villages of Poldasht County, Iran. All the data and information on the prevalence of bone diseases were obtained from the Health Record Department, Poldasht Health Centre. To obtain the odds ratio of bone disease problem in different risk factors, when considering the cluster effect of rural area, logistic regression in a multilevel model was used. Results showed that skeletal fluorosis of people who live in areas with high fluoride concentration is 18.1% higher than that of individuals who live in areas with low fluoride concentration. Skeletal fluorosis (54.5%) was observed in the age group of 71 years and above, and was more commonly found in females than males. According to Unadjusted, individuals who consume ≤3 unit milk and dairy products per week have almost the same level of bone diseases as compared to those that consume more than 3 units. This study indicated that, skeletal fluorosis is a general health problem in these rural areas because the results revealed that high percentage of the studied population had symptoms of skeletal fluorosis.

Skeletal surveys in multiple myeloma

International Nuclear Information System (INIS)

Sebes, J.I.; Niell, H.B.; Palmieri, G.M.A.; Reidy, T.J.

1986-01-01

Thirty-three patients with multiple myeloma were studied with serial skeletal surveys, serum immunoglobulin levels, and postabsorptive urinary hydroxyproline (Spot-HYPRO) determinations. Twenty receiving chemotherapy were also followed with skeletal surveys in order to evaluate bone response to treatment. A close association was found between skeletal findings and changes in immunoglubulin levels with positive correlation in 71% of the patients. A similar association was found between skeletal disease and Spot-HYPRO level changes in 65%. Five of 12 patients (42%) with partial or complete clinical response to chemotherapy, demonstrated improvement in the appearance of skeletal lesions. Positive correlation between the roentgenographic changes and clinical markers of myeloma as well as therapeutic response, indicates that skeletal surveys are useful and effective in monitoring patients with multiple myeloma. (orig.)

Can hydrocarbons entrapped in seep carbonates serve as gas geochemistry recorder?

Science.gov (United States)

Blumenberg, Martin; Pape, Thomas; Seifert, Richard; Bohrmann, Gerhard; Schlömer, Stefan

2018-04-01

The geochemistry of seep gases is useful for an understanding of the local petroleum system. Here it was tested whether individual light hydrocarbons in seep gases are representatively entrapped in authigenic carbonates that formed near active seep sites. If applicable, it would be possible to extract geochemical information not only on the origin but also on the thermal maturity of the hydrocarbon source rocks from the gases entrapped in carbonates in the past. Respective data could be used for a better understanding of paleoenvironments and might directly serve as calibration point for, amongst others, petroleum system modeling. For this approach, (sub)-recent seep carbonates from the Black Sea (Paleodnjepr region and Batumi seep area), two sites of the Campeche Knoll region in the Gulf of Mexico, and the Venere mud volcano (Mediterranean Sea) were selected. These seep carbonates derive from sites for which geochemical data on the currently seeping gases exist. During treatment with phosphoric acid, methane and higher hydrocarbons were released from all carbonates, but in low concentrations. Compositional studies demonstrate that the ratio of methane to the sum of higher hydrocarbons (C1/(C2+C3)) is (partly strongly) positively biased in the entrapped gas fraction. δ13C values of C1 were determined for all samples and, for the samples from the Gulf of Mexico and the Mediterranean Sea, also of C2 and C3. The present dataset from six seep sites indicates that information on the seeped methane can be—although with a scatter of several permil—recorded in seep carbonate matrices, but other valuable information like the composition and δ13C of ethane and propane appears to be modified or lost during, for example, enclosure or at an early stage of diagenesis.

Compiled records of carbon isotopes in atmospheric CO2 for historical simulations in CMIP6

Directory of Open Access Journals (Sweden)

H. Graven

2017-12-01

Full Text Available The isotopic composition of carbon (Δ14C and δ13C in atmospheric CO2 and in oceanic and terrestrial carbon reservoirs is influenced by anthropogenic emissions and by natural carbon exchanges, which can respond to and drive changes in climate. Simulations of 14C and 13C in the ocean and terrestrial components of Earth system models (ESMs present opportunities for model evaluation and for investigation of carbon cycling, including anthropogenic CO2 emissions and uptake. The use of carbon isotopes in novel evaluation of the ESMs' component ocean and terrestrial biosphere models and in new analyses of historical changes may improve predictions of future changes in the carbon cycle and climate system. We compile existing data to produce records of Δ14C and δ13C in atmospheric CO2 for the historical period 1850–2015. The primary motivation for this compilation is to provide the atmospheric boundary condition for historical simulations in the Coupled Model Intercomparison Project 6 (CMIP6 for models simulating carbon isotopes in the ocean or terrestrial biosphere. The data may also be useful for other carbon cycle modelling activities.

Compiled records of carbon isotopes in atmospheric CO2 for historical simulations in CMIP6

Science.gov (United States)

Graven, Heather; Allison, Colin E.; Etheridge, David M.; Hammer, Samuel; Keeling, Ralph F.; Levin, Ingeborg; Meijer, Harro A. J.; Rubino, Mauro; Tans, Pieter P.; Trudinger, Cathy M.; Vaughn, Bruce H.; White, James W. C.

2017-12-01

The isotopic composition of carbon (Δ14C and δ13C) in atmospheric CO2 and in oceanic and terrestrial carbon reservoirs is influenced by anthropogenic emissions and by natural carbon exchanges, which can respond to and drive changes in climate. Simulations of 14C and 13C in the ocean and terrestrial components of Earth system models (ESMs) present opportunities for model evaluation and for investigation of carbon cycling, including anthropogenic CO2 emissions and uptake. The use of carbon isotopes in novel evaluation of the ESMs' component ocean and terrestrial biosphere models and in new analyses of historical changes may improve predictions of future changes in the carbon cycle and climate system. We compile existing data to produce records of Δ14C and δ13C in atmospheric CO2 for the historical period 1850-2015. The primary motivation for this compilation is to provide the atmospheric boundary condition for historical simulations in the Coupled Model Intercomparison Project 6 (CMIP6) for models simulating carbon isotopes in the ocean or terrestrial biosphere. The data may also be useful for other carbon cycle modelling activities.

Whole-body MRI in comparison to skeletal scintigraphy for detection of skeletal metastases in patients with solid tumors

International Nuclear Information System (INIS)

Ghanem, N.; Altehoefer, C.; Winterer, J.; Schaefer, O.; Bley, T.A.; Langer, M.; Kelly, T.; Moser, E.

2004-01-01

The aim of this study was to compare the diagnostic efficacy of whole-body magnetic resonance imaging (WB-MRI) as a new and rapid examination technique with skeletal scintigraphy for detection of skeletal metastases from solid tumors. In 129 patients with solid malignant tumors, WB-MRI was performed for individual comparison with skeletal scintigraphy. Examinations were performed with the innovative AngioSURF trademark rolling table with integrated phased array surface coil and coronary TIRM sequences for different body regions. The results for WB-MRI and skeletal scintigraphy were concordant in 81% of the cases, whereby both procedures excluded skeletal metastases in 43%. WB-MRI and skeletal scintigraphy demonstrated skeletal metastases in 38% of the cases, whereby WB-MRI provided more comprehensive findings in 45%. In 12% of the cases, skeletal scintigraphy was superior to WB-MRI and in 19% the findings were discordant, whereby WB-MRI detected skeletal metastases in 15 cases which had not been found on skeletal scintigraphy. In nine cases, skeletal scintigraphy was positive when the WB-MRI was negative. In 60% of the cases, WB-MRI evidenced tumor-associated findings. WB-MRI represents a promising new staging technique for detection of skeletal metastases, which is more sensitive in many cases than skeletal scintigraphy in detecting and assessing the extent of skeletal metastases - and tumor-associated findings that are relevant for treatment strategy. (orig.) [de

Lyophilized skeletal imaging composition

International Nuclear Information System (INIS)

Vanduzee, B.F.

1983-01-01

This invention encompasses a process for producing a dry-powder skeletal imaging kit. An aqueous solution of a diphosphonate, a stannous reductant, and, optionally, a stabilizer is prepared. The solution is adjusted to a pH within the range 4.2 to 4.8 and the pH-adjusted solution is then lyophilized. The adjustment of pH, within a particular range, during the process of manufacturing lyophilized diphosphonate containing skeletal imaging kits yields a kit which produces a technetium skeletal imaging agent with superior imaging properties. This improved performance is manifested through faster blood clearance and higher skeletal uptake of the technetium imaging agent

Refining the Neoproterozoic and Early Paleozoic record of carbon cycling and seawater chemistry using quantitative geochemical models of redox dynamics and carbonate diagenesis

DEFF Research Database (Denmark)

Ahm, Anne-Sofie Crüger

based records. Despite the prevalence of diagenesis in sedimentary rocks there are currently few robust geochemical tools capable of providing quantitative information on the extent of alteration from the primary signal. In order to fill this gap, Chapter 3 presents a numerical model of marine carbonate...... through diagenesis and provide more robust estimates for past seawater chemistry. Ancient carbonate rocks with extreme negative carbon isotopes are found worldwide bracketing the Marinoan glaciation (∼635 Ma). There is no scientific consensus as to whether these excursions originate from a primary...... perturbation in the carbon cycle or from diagenetic alterations. Chapter 4 merges new measurements of calcium, magnesium, and strontium isotopes in these sediments with the diagenetic model developed in Chapter 3 to offer new insights into the potential origin of these extreme isotope anomalies....

Cardiac troponin T and fast skeletal muscle denervation in ageing.

Science.gov (United States)

Xu, Zherong; Feng, Xin; Dong, Juan; Wang, Zhong-Min; Lee, Jingyun; Furdui, Cristina; Files, Daniel Clark; Beavers, Kristen M; Kritchevsky, Stephen; Milligan, Carolanne; Jin, Jian-Ping; Delbono, Osvaldo; Zhang, Tan

2017-10-01

Ageing skeletal muscle undergoes chronic denervation, and the neuromuscular junction (NMJ), the key structure that connects motor neuron nerves with muscle cells, shows increased defects with ageing. Previous studies in various species have shown that with ageing, type II fast-twitch skeletal muscle fibres show more atrophy and NMJ deterioration than type I slow-twitch fibres. However, how this process is regulated is largely unknown. A better understanding of the mechanisms regulating skeletal muscle fibre-type specific denervation at the NMJ could be critical to identifying novel treatments for sarcopenia. Cardiac troponin T (cTnT), the heart muscle-specific isoform of TnT, is a key component of the mechanisms of muscle contraction. It is expressed in skeletal muscle during early development, after acute sciatic nerve denervation, in various neuromuscular diseases and possibly in ageing muscle. Yet the subcellular localization and function of cTnT in skeletal muscle is largely unknown. Studies were carried out on isolated skeletal muscles from mice, vervet monkeys, and humans. Immunoblotting, immunoprecipitation, and mass spectrometry were used to analyse protein expression, real-time reverse transcription polymerase chain reaction was used to measure gene expression, immunofluorescence staining was performed for subcellular distribution assay of proteins, and electromyographic recording was used to analyse neurotransmission at the NMJ. Levels of cTnT expression in skeletal muscle increased with ageing in mice. In addition, cTnT was highly enriched at the NMJ region-but mainly in the fast-twitch, not the slow-twitch, muscle of old mice. We further found that the protein kinase A (PKA) RIα subunit was largely removed from, while PKA RIIα and RIIβ are enriched at, the NMJ-again, preferentially in fast-twitch but not slow-twitch muscle in old mice. Knocking down cTnT in fast skeletal muscle of old mice: (i) increased PKA RIα and reduced PKA RIIα at the NMJ; (ii

Skeletal imaging composition

International Nuclear Information System (INIS)

Vanduzee, B.F.; Degenhardt, C.R.

1983-01-01

This invention is based on the discovery that the adjustment of pH, within a particular range, during the process of manufacturing lyophilized diphosphonate-containing skeletal imaging kits yields a kit which produces a technetium skeletal imaging agent with superior imaging properties. This increased performance is manifested through faster blood clearance and higher skeletal uptake of the technetium imaging agent. The process for producing a dry-powder imaging kit comprises the steps of: preparing a solution of a diphosphonate carrier, stannous reductant, and a stabilizer in water; adjusting the pH to between 5.5 and 6.5; and lyophilizing the solution

Proteomic profiling of non-obese type 2 diabetic skeletal muscle.

Science.gov (United States)

Mullen, Edel; Ohlendieck, Kay

2010-03-01

Abnormal glucose handling has emerged as a major clinical problem in millions of diabetic patients worldwide. Insulin resistance affects especially one of the main target organs of this hormone, the skeletal musculature, making impaired glucose metabolism in contractile fibres a major feature of type 2 diabetes. High levels of circulating free fatty acids, an increased intramyocellular lipid content, impaired insulin-mediated glucose uptake, diminished mitochondrial functioning and an overall weakened metabolic flexibility are pathobiochemical hallmarks of diabetic skeletal muscles. In order to increase our cellular understanding of the molecular mechanisms that underlie this complex diabetes-associated skeletal muscle pathology, we initiated herein a mass spectrometry-based proteomic analysis of skeletal muscle preparations from the non-obese Goto-Kakizaki rat model of type 2 diabetes. Following staining of high-resolution two-dimensional gels with colloidal Coomassie Blue, 929 protein spots were detected, whereby 21 proteins showed a moderate differential expression pattern. Decreased proteins included carbonic anhydrase, 3-hydroxyisobutyrate dehydrogenase and enolase. Increased proteins were identified as monoglyceride lipase, adenylate kinase, Cu/Zn superoxide dismutase, phosphoglucomutase, aldolase, isocitrate dehydrogenase, cytochrome c oxidase, small heat shock Hsp27/B1, actin and 3-mercaptopyruvate sulfurtransferase. These proteomic findings suggest that the diabetic phenotype is associated with a generally perturbed protein expression pattern, affecting especially glucose, fatty acid, nucleotide and amino acid metabolism, as well as the contractile apparatus, the cellular stress response, the anti-oxidant defense system and detoxification mechanisms. The altered expression levels of distinct skeletal muscle proteins, as documented in this study, might be helpful for the future establishment of a comprehensive biomarker signature of type 2 diabetes

Scale and the isotopic record of C4 plants in pedogenic carbonate: from the biome to the rhizospere.

Energy Technology Data Exchange (ETDEWEB)

Monger, Dr. H Curtis [New Mexico State University, Las Cruces; Cole, David R [ORNL; Buck, Dr. Brenda [University of Nevada, Las Vegas; Gallegos, Robert [Sant fe Water Division

2009-01-01

The 13C/12C ratio in pedogenic carbonate (i.e., CaCO3 formed in soil) is a significant tool for investigating C4 biomes of the past. However, the paleoecological meaning of d13C values in pedogenic carbonate can change with the scale at which one considers the data. We describe studies of modern soils, fossil soils, and vegetation change in the Chihuahuan Desert of North America and elsewhere that reveal four scales important for paleoecologic interpretations. (1) At the broadest scale, the biome scale (hundreds to millions of km2), an isotopic record interpreted as C3 vegetation replacing C4 grasslands may indicate invading C3 woody shrubs instead of expanding C3 forests (a common interpretation). (2) At the landscape scale (several tens of m2 to hundreds of km2), the accuracy of scaling up paleoclimatic interpretations to a regional level is affected by the landform containing the isotopic record. (3) At the soil-profile scale (cm2 to m2), soil profiles with multiple generations of carbonate mixed together have a lower-resolution paleoecologic record than soil profiles repeatedly buried. (4) At the rhizosphere scale (lm2 to cm2), carbonate formed on roots lack the 14 17 enrichment observed at broader scales, revealing different fractionation processes at different scales. A multi-scale approach in dealing with d13C in pedogenic carbonate will increase the accuracy of paleoecologic interpretations and understanding of soil geomorphic climatic interactions that affect boundaries between C4 and C3 vegetation.

Scale and the isotopic record of C4 plants in pedogenic carbonate: from the biome to the rhizosphere

Energy Technology Data Exchange (ETDEWEB)

Monger, Dr. H Curtis [New Mexico State University, Las Cruces; Cole, David [Ohio State University; Buck, Dr. Brenda [University of Nevada, Las Vegas; Gallegos, Robert [Sant fe Water Division

2009-01-01

The 13C/12C ratio in pedogenic carbonate (i.e., CaCO3 formed in soil) is a significant tool for investigating C4 biomes of the past. However, the paleoecological meaning of d13C values in pedogenic carbonate can change with the scale at which one considers the data. We describe studies of modern soils, fossil soils, and vegetation change in the Chihuahuan Desert of North America and elsewhere that reveal four scales important for paleoecologic interpretations. (1) At the broadest scale, the biome scale (hundreds to millions of km2), an isotopic record interpreted as C3 vegetation replacing C4 grasslands may indicate invading C3 woody shrubs instead of expanding C3 forests (a common interpretation). (2) At the landscape scale (several tens of m2 to hundreds of km2), the accuracy of scaling up paleoclimatic interpretations to a regional level is affected by the landform containing the isotopic record. (3) At the soil-profile scale (cm2 to m2), soil profiles with multiple generations of carbonate mixed together have a lower-resolution paleoecologic record than soil profiles repeatedly buried. (4) At the rhizosphere scale (lm2 to cm2), carbonate formed on roots lack the 14 17 enrichment observed at broader scales, revealing different fractionation processes at different scales. A multi-scale approach in dealing with d13C in pedogenic carbonate will increase the accuracy of paleoecologic interpretations and understanding of soil geomorphic climatic interactions that affect boundaries between C4 and C3 vegetation.

Rich table but short life: Diffuse idiopathic skeletal hyperostosis in Danish astronomer Tycho Brahe (1546-1601) and its possible consequences

Science.gov (United States)

Kacki, Sacha; Lynnerup, Niels; Kaupová, Sylva; Jeanson, Alizé Lacoste; Povýšil, Ctibor; Horák, Martin; Kučera, Jan; Rasmussen, Kaare Lund; Podliska, Jaroslav; Dragoun, Zdeněk; Smolík, Jiří; Vellev, Jens; Brůžek, Jaroslav

2018-01-01

The exhumation of Danish astronomer Tycho Brahe (1546–1601) was performed in 2010 to verify speculative views on the cause of his death. Previous analyses of skeletal and hair remains recovered from his grave refuted the presumption that he died from poisoning. These studies also outlined the possibility that he actually died from an acute illness, echoing the rather vague and inaccurate testimony of some historical records. We performed a detailed paleopathological analysis of Tycho Brahe’s skeletal remains, along with a reconstruction of his diet based on carbon and nitrogen stable isotopes analysis and an estimate of his physical status (relative body fat) based on medullar and cortical dimensions of the femoral shaft. The astronomer’s remains exhibit bone changes indicative of diffuse idiopathic skeletal hyperostosis (DISH). The study further allows us to classify him as obese (100% reliability according to our decision tree designed from Danish males), and points out his rich diet (high input of animal protein and/or marine resources) and high social status. Comorbidities of DISH and obesity are reviewed, and their influence on health status is discussed. We further consider some conditions associated with metabolic syndrome as possible causes of Tycho Brahe’s final symptoms (urinary retention, renal failure and coma), including diabetes, alcoholic ketoacidosis and benign prostatic hypertrophy. Although a definite and specific diagnosis cannot be established, our study points to today’s civilization diseases often associated with DISH and metabolic syndrome as the possible cause of death of Tycho Brahe. PMID:29672561

Comparative Study of Skeletal Stability between Postoperative Skeletal Intermaxillary Fixation and No Skeletal Fixation after Bilateral Sagittal Split Ramus Osteotomy

DEFF Research Database (Denmark)

Hartlev, Jens; Godtfredsen, Erik; Andersen, Niels Trolle

2014-01-01

OBJECTIVES: The purpose of the present study was to evaluate skeletal stability after mandibular advancement with bilateral sagittal split osteotomy. MATERIAL AND METHODS: Twenty-six patients underwent single-jaw bilateral sagittal split osteotomy (BSSO) to correct skeletal Class II malocclusion....

The Strontium Isotope Record of Zavkhan Terrane Carbonates: Strontium Isotope Stability Through the Ediacaran-Cambrian Transition

OpenAIRE

Petach, Tanya N.

2015-01-01

First order trends in the strontium isotopic (87Sr/86Sr) composition of seawater are controlled by radiogenic inputs from the continent and non-radiogenic inputs from exchange at mid-ocean ridges. Carbonates precipitated in seawater preserve trace amounts of strontium that record this isotope ratio and therefore record the relative importance of mid-ocean ridge and weathering chemical inputs to sea water composition. It has been proposed that environmental changes during the Ediacaran-Cambria...

First report of fossil "keratose" demosponges in Phanerozoic carbonates: preservation and 3-D reconstruction.

Science.gov (United States)

Luo, Cui; Reitner, Joachim

2014-06-01

Fossil record of Phanerozoic non-spicular sponges, beside of being important with respect to the lineage evolution per se, could provide valuable references for the investigation of Precambrian ancestral animal fossils. However, although modern phylogenomic studies resolve non-spicular demosponges as the sister group of the remaining spiculate demosponges, the fossil record of the former is extremely sparse or unexplored compared to that of the latter; the Middle Cambrian Vauxiidae Walcott 1920, is the only confirmed fossil taxon of non-spicular demosponges. Here, we describe carbonate materials from Devonian (Upper Givetian to Lower Frasnian) bioherms of northern France and Triassic (Anisian) microbialites of Poland that most likely represent fossil remnants of keratose demosponges. These putative fossils of keratose demosponges are preserved as automicritic clumps. They are morphologically distinguishable from microbial fabrics but similar to other spiculate sponge fossils, except that the skeletal elements consist of fibrous networks instead of assembled spicules. Consistent with the immunological behavior of sponges, these fibrous skeletons often form a rim at the edge of the automicritic aggregate, separating the inner part of the aggregate from foreign objects. To confirm the architecture of these fibrous networks, two fossil specimens and a modern thorectid sponge for comparison were processed for three-dimensional (3-D) reconstruction using serial grinding tomography. The resulting fossil reconstructions are three-dimensionally anastomosing, like modern keratose demosponges, but their irregular and nonhierarchical meshes indicate a likely verongid affinity, although a precise taxonomic conclusion cannot be made based on the skeletal architecture alone. This study is a preliminary effort, but an important start to identify fossil non-spicular demosponges in carbonates and to re-evaluate their fossilization potential.

Tomographic elastography of contracting skeletal muscles from their natural vibrations

Science.gov (United States)

Sabra, Karim G.; Archer, Akibi

2009-11-01

Conventional elastography techniques require an external mechanical or radiation excitation to measure noninvasively the viscoelastic properties of skeletal muscles and thus monitor human motor functions. We developed instead a passive elastography technique using only an array of skin-mounted accelerometers to record the low-frequency vibrations of the biceps brachii muscle naturally generated during voluntary contractions and to determine their two-dimensional directionality. Cross-correlating these recordings provided travel-times measurements of these muscle vibrations between multiple sensor pairs. Travel-time tomographic inversions yielded spatial variations of their propagation velocity during isometric elbow flexions which indicated a nonuniform longitudinal stiffening of the biceps.

Skeletal muscle atrophy in bioengineered skeletal muscle: a new model system.

Science.gov (United States)

Lee, Peter H U; Vandenburgh, Herman H

2013-10-01

Skeletal muscle atrophy has been well characterized in various animal models, and while certain pathways that lead to disuse atrophy and its associated functional deficits have been well studied, available drugs to counteract these deficiencies are limited. An ex vivo tissue-engineered skeletal muscle offers a unique opportunity to study skeletal muscle physiology in a controlled in vitro setting. Primary mouse myoblasts isolated from adult muscle were tissue engineered into bioartificial muscles (BAMs) containing hundreds of aligned postmitotic muscle fibers expressing sarcomeric proteins. When electrically stimulated, BAMs generated measureable active forces within 2-3 days of formation. The maximum isometric tetanic force (Po) increased for ∼3 weeks to 2587±502 μN/BAM and was maintained at this level for greater than 80 days. When BAMs were reduced in length by 25% to 50%, muscle atrophy occurred in as little as 6 days. Length reduction resulted in significant decreases in Po (50.4%), mean myofiber cross-sectional area (21.7%), total protein synthesis rate (22.0%), and noncollagenous protein content (6.9%). No significant changes occurred in either the total metabolic activity or protein degradation rates. This study is the first in vitro demonstration that length reduction alone can induce skeletal muscle atrophy, and establishes a novel in vitro model for the study of skeletal muscle atrophy.

An atlas of normal skeletal scintigraphy

International Nuclear Information System (INIS)

Flanagan, J.J.; Maisey, M.N.

1985-01-01

This atlas was compiled to provide the neophyte as well as the experienced radiologist and the nuclear medicine physician with a reference on normal skeletal scintigraphy as an aid in distinguishing normal variations in skeletal uptake from abnormal findings. Each skeletal scintigraph is labeled, and utilizing an identical scale, a relevant skeletal photograph and radiograph are placed adjacent to the scintigraph

The exercised skeletal muscle: a review

Directory of Open Access Journals (Sweden)

Marina Marini

2010-09-01

Full Text Available The skeletal muscle is the second more plastic tissue of the body - second to the nervous tissue only. In fact, both physical activity and inactivity contribute to modify the skeletal muscle, by continuous signaling through nerve impulses, mechanical stimuli and humoral clues. In turn, the skeletal muscle sends signals to the body, thus contributing to its homeostasis. We'll review here the contribute of physical exercise to the shaping of skeletal muscle, to the adaptation of its mass and function to the different needs imposed by different physical activities and to the attainment of the health benefits associated with active skeletal muscles. Focus will primarily be on the molecular pathways and on gene regulation that result in skeletal muscle adaptation to exercise.

in Skeletal Muscle

Directory of Open Access Journals (Sweden)

Espen E. Spangenburg

2011-01-01

Full Text Available Triglyceride storage is altered across various chronic health conditions necessitating various techniques to visualize and quantify lipid droplets (LDs. Here, we describe the utilization of the BODIPY (493/503 dye in skeletal muscle as a means to analyze LDs. We found that the dye was a convenient and simple approach to visualize LDs in both sectioned skeletal muscle and cultured adult single fibers. Furthermore, the dye was effective in both fixed and nonfixed cells, and the staining seemed unaffected by permeabilization. We believe that the use of the BODIPY (493/503 dye is an acceptable alternative and, under certain conditions, a simpler method for visualizing LDs stored within skeletal muscle.

Skeletal sequelae of radiation therapy for malignant childhood tumors

International Nuclear Information System (INIS)

Butler, M.S.; Robertson, W.W. Jr.; Rate, W.; D'Angio, G.J.; Drummond, D.S.

1990-01-01

One hundred forty-three patients who received radiation therapy for childhood tumors, and survived to the age of skeletal maturity, were studied by retrospective review of oncology records and roentgenograms. Diagnoses for the patients were the following: Hodgkin's lymphoma (44), Wilms's tumor (30), acute lymphocytic leukemia (26), non-Hodgkin's lymphoma (18), Ewing's sarcoma (nine), rhabdomyosarcoma (six), neuroblastoma (six), and others (four). Age at the follow-up examination averaged 18 years (range, 14-28 years). Average length of follow-up study was 9.9 years (range, two to 18 years). Asymmetry of the chest and ribs was seen in 51 (36%) of these children. Fifty (35%) had scoliosis; 14 had kyphosis. In two children, the scoliosis was treated with a brace, while one developed significant kyphosing scoliosis after laminectomy and had spinal fusion. Twenty-three (16%) patients complained of significant pain at the radiation sites. Twelve of the patients developed leg-length inequality; eight of those were symptomatic. Three patients developed second primary tumors. Currently, the incidence of significant skeletal sequelae is lower and the manifestations are less severe than reported in the years from 1940 to 1970. The reduction in skeletal complications may be attributed to shielding of growth centers, symmetric field selection, decreased total radiation doses, and sequence changes in chemotherapy

Congenital anomalies and normal skeletal variants

International Nuclear Information System (INIS)

Guebert, G.M.; Yochum, T.R.; Rowe, L.J.

1987-01-01

Congenital anomalies and normal skeletal variants are a common occurrence in clinical practice. In this chapter a large number of skeletal anomalies of the spine and pelvis are reviewed. Some of the more common skeletal anomalies of the extremities are also presented. The second section of this chapter deals with normal skeletal variants. Some of these variants may simulate certain disease processes. In some instances there are no clear-cut distinctions between skeletal variants and anomalies; therefore, there may be some overlap of material. The congenital anomalies are presented initially with accompanying text, photos, and references, beginning with the skull and proceeding caudally through the spine to then include the pelvis and extremities. The normal skeletal variants section is presented in an anatomical atlas format without text or references

Skeletal Stability after Large Mandibular Advancement (> 10 mm) with Bilateral Sagittal Split Osteotomy and Skeletal Elastic Intermaxillary Fixation

DEFF Research Database (Denmark)

Schwartz, Kristoffer; Rodrigo, Maria; Jensen, Thomas

2016-01-01

OBJECTIVES: The aim of the present study was to assess the skeletal stability after large mandibular advancement (> 10 mm) with bilateral sagittal split osteotomy and skeletal elastic intermaxillary fixation and to correlate the skeletal stability with the vertical facial type. MATERIAL AND METHODS......: A total of 33 consecutive patients underwent bimaxillary surgery to correct skeletal Class II malocclusion with a mandibular advancement (> 10 mm) measured at B-point and postoperative skeletal elastic intermaxillary fixation for 16 weeks. Skeletal stability was evaluated using lateral cephalometric...... radiographs obtained preoperative (T1), 8 weeks postoperatively (T2), and 18 month postoperatively (T3). B-point and pogonion (Pog) was used to measure the skeletal relapse and the mandibular plane angle (MP-angle) was used to determine the vertical facial type. RESULTS: The mean advancement from T1 to T2...

Skeletal manifestations of juvenile hypothyroidism and the impact of treatment on skeletal system.

Science.gov (United States)

Gutch, Manish; Philip, Rajeev; Philip, Renjit; Toms, Ajit; Saran, Sanjay; Gupta, K K

2013-10-01

Thyroid hormone mediates growth and development of the skeleton through its direct effects and through its permissive effects on growth hormone. The effect of hypothyroidism on bone is well described in congenital hypothyroidism, but the impact of thyroid hormone deficiency on a growing skeleton, as it happens with juvenile hypothyroidism, is less defined. In addition, the extent to which the skeletal defects of juvenile hypothyroidism revert on the replacement of thyroid hormone is not known. A study was undertaken in 29 juvenile autoimmune hypothyroid patients to study the skeletal manifestations of juvenile hypothyroidism and the impact of treatment of hypothyroidism on the skeletal system of juvenile patients. Hypothyroidism has a profound impact on the skeletal system and delayed bone age, dwarfism, and thickened bands at the metaphyseal ends being the most common findings. Post treatment, skeletal findings like delayed bone age and dwarfism improved significantly, but there were no significant changes in enlargement of sella, presence of wormian bones, epihyseal dysgenesis, vertebral changes and thickened band at the metaphyseal ends. With the treatment of hypothyroidism, there is an exuberant advancement of bone age, the catch up of bone age being approximately double of the chronological age advancement.

Expression of Gla proteins during fish skeletal development

OpenAIRE

Gavaia, Paulo J.

2006-01-01

Senegal sole skeletal development; Skeletal malformations; Skeletal malformation in mediterranean species; Senegal sole skeletal deformities; Zebra fish as model system: skeletal development; Identification of bone cells / skeletal development; Spatial - temporal pattern of bgp expression; Single cell resolution: localization of bgp mRNA; Single cell resolution: Immunolocalization of Bgp; Single cell resolution: localization of mgp mRNA; Single cell resolution: Immunolocalization of Mgp; An i...

Skeletal muscle performance and ageing.

Science.gov (United States)

Tieland, Michael; Trouwborst, Inez; Clark, Brian C

2018-02-01

The world population is ageing rapidly. As society ages, the incidence of physical limitations is dramatically increasing, which reduces the quality of life and increases healthcare expenditures. In western society, ~30% of the population over 55 years is confronted with moderate or severe physical limitations. These physical limitations increase the risk of falls, institutionalization, co-morbidity, and premature death. An important cause of physical limitations is the age-related loss of skeletal muscle mass, also referred to as sarcopenia. Emerging evidence, however, clearly shows that the decline in skeletal muscle mass is not the sole contributor to the decline in physical performance. For instance, the loss of muscle strength is also a strong contributor to reduced physical performance in the elderly. In addition, there is ample data to suggest that motor coordination, excitation-contraction coupling, skeletal integrity, and other factors related to the nervous, muscular, and skeletal systems are critically important for physical performance in the elderly. To better understand the loss of skeletal muscle performance with ageing, we aim to provide a broad overview on the underlying mechanisms associated with elderly skeletal muscle performance. We start with a system level discussion and continue with a discussion on the influence of lifestyle, biological, and psychosocial factors on elderly skeletal muscle performance. Developing a broad understanding of the many factors affecting elderly skeletal muscle performance has major implications for scientists, clinicians, and health professionals who are developing therapeutic interventions aiming to enhance muscle function and/or prevent mobility and physical limitations and, as such, support healthy ageing. © 2017 The Authors. Journal of Cachexia, Sarcopenia and Muscle published by John Wiley & Sons Ltd on behalf of the Society on Sarcopenia, Cachexia and Wasting Disorders.

A Study on Generic Representation of Skeletal Remains Replication of Prehistoric Burial

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C.-W. Shao

2015-08-01

Full Text Available Generic representation of skeletal remains from burials consists of three dimensions which include physical anthropologists, replication technicians, and promotional educators. For the reason that archaeological excavation is irreversible and disruptive, detail documentation and replication technologies are surely needed for many purposes. Unearthed bones during the process of 3D digital scanning need to go through reverse procedure, 3D scanning, digital model superimposition, rapid prototyping, mould making, and the integrated errors generated from the presentation of colours and textures are important issues for the presentation of replicate skeleton remains among professional decisions conducted by physical anthropologists, subjective determination of makers, and the expectations of viewers. This study presents several cases and examines current issues on display and replication technologies for human skeletal remains of prehistoric burials. This study documented detail colour changes of human skeleton over time for the reference of reproduction. The tolerance errors of quantification and required technical qualification is acquired according to the precision of 3D scanning, the specification requirement of rapid prototyping machine, and the mould making process should following the professional requirement for physical anthropological study. Additionally, the colorimeter is adopted to record and analyse the “colour change” of the human skeletal remains from wet to dry condition. Then, the “colure change” is used to evaluate the “real” surface texture and colour presentation of human skeletal remains, and to limit the artistic presentation among the human skeletal remains reproduction. The“Lingdao man No.1”, is a well preserved burial of early Neolithic period (8300 B.P. excavated from Liangdao-Daowei site, Matsu, Taiwan , as the replicating object for this study. In this study, we examined the reproduction procedures step by

Comparative photoelastic study of dental and skeletal anchorages in the canine retraction

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Cristiane Aparecida de Assis Claro

2014-01-01

Full Text Available OBJECTIVE: To compare dental and skeletal anchorages in mandibular canine retraction by means of a stress distribution analysis. METHODS: A photoelastic model was produced from second molar to canine, without the first premolar, and mandibular canine retraction was simulated by a rubber band tied to two types of anchorage: dental anchorage, in the first molar attached to adjacent teeth, and skeletal anchorage with a hook simulating the mini-implant. The forces were applied 10 times and observed in a circular polariscope. The stresses located in the mandibular canine were recorded in 7 regions. The Mann-Whitney test was employed to compare the stress in each region and between both anchorage systems. The stresses in the mandibular canine periradicular regions were compared by the Kruskal-Wallis test. RESULTS: Stresses were similar in the cervical region and the middle third. In the apical third, the stresses associated with skeletal anchorage were higher than the stresses associated with dental anchorage. The results of the Kruskal-Wallis test showed that the highest stresses were identified in the cervical-distal, apical-distal, and apex regions with the use of dental anchorage, and in the apical-distal, apical-mesial, cervical-distal, and apex regions with the use of skeletal anchorage. CONCLUSIONS: The use of skeletal anchorage in canine retraction caused greater stress in the apical third than the use of dental anchorage, which indicates an intrusive component resulting from the direction of the force due to the position of the mini-implant and the bracket hook of the canine.

[Clinical observation of 5 cases of diabetes insipidus complicated with skeletal fluorosis].

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Wang, Shuan-Chi; Tao, Xiao-Bing; Wang, Fang-Fang; Zhang, Nan

2017-07-25

To investigate the mechanism of diabetes insipidus complicated with skeletal fluorosis and the surgical treatment of spinal canal stenosis caused by skeletal fluorosis. From January 2000 to November 2011, 5 patients with diabetes insipidus complicated with skeletal fluorosis were treated with drug and cervical or thoracic posterior decompression including 2 males and 3 females with age of 35, 45, 47, 49, 55 years old respectively. The symptoms was mainly limb motor sensory disturbance accompanied by polyuria and polyuria. Imaging showed that cervical and thoracic multi-segmental continuous spinal stenosis. It was diagnosed with diabetes insipidus according to the symptoms and laboratory tests. According to the symptoms, the vertebral with problems were located and treated by posterior laminectomy decompression or the expansive open-door laminectomy. The recovery of neurological symptoms were recorded and the operation result were evaluate by JOA score improvement rate. The wound healed well in 5 cases, and 1 case of cervical axial pain was improved after symptomatic treatment. Five patients were followed up for 2 to 6 years with an average of 4 years. Numbness of limb and weakness symptoms of follow-up patients were significantly improved, muscle strength and acupuncture hypothyroidism were significantly improved compared with preoperative, the JOA score was significantly improved. At the final follow-up, the improvement rate got excellent results in 2 cases, good in 2 and fair in 1. Long-term high intake of fluoride can cause skeletal fluorosis in patients with diabetes insipidus. The posterior decompression is effective for the majority of spinal canal stenosis caused by skeletal fluorosis.

Oncological outcomes of patients with Ewing's sarcoma: is there a difference between skeletal and extra-skeletal Ewing's sarcoma?

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Pradhan, A; Grimer, R J; Spooner, D; Peake, D; Carter, S R; Tillman, R M; Abudu, A; Jeys, L

2011-04-01

The aim of this study was to identify whether there was any difference in patient, tumour, treatment or outcome characteristics between patients with skeletal or extra-skeletal Ewing's sarcoma. We identified 300 patients with new primary Ewing's sarcoma diagnosed between 1980 and 2005 from the centres' local database. There were 253 (84%) with skeletal and 47 (16%) with extra-skeletal Ewing's sarcomas. Although patients with skeletal Ewing's were younger (mean age 16.8 years) than those with extra-skeletal Ewing's sarcoma (mean age 27.5 years), there was little difference between the groups in terms of tumour stage or treatment. Nearly all the patients were treated with chemotherapy and most had surgery. There was no difference in the overall survival of patients with skeletal (64%) and extra-skeletal Ewing's sarcoma (61%) (p = 0.85), and this was also the case when both groups were split by whether they had metastases or not. This large series has shown that the oncological outcomes of Ewing's sarcoma are related to tumour characteristics and patient age, and not determined by whether they arise in bone or soft tissue.

A Comparison of Recent Organic and Inorganic Carbon Isotope Records: Why Do They Covary in Some Settings and Not In Others?

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Oehlert, A. M.; Swart, P. K.

2013-12-01

Covariance between inorganic and organic δ13C records has been used to determine whether a deposit has been altered by diagenesis, how the dynamics of the global carbon cycle changed during the production of the sediments in the deposit, and also for chronostratigraphic correlations. Although covariant records are observed in the ancient geologic record in a variety of depositional environments, such comparisons are not widely applied to modern deposits where definitive data regarding sediment producers, sea level fluctuations, and changes in the global carbon cycle are available. This study uses paired δ13C records from cores collected by the Ocean Drilling Program from three modern periplatform settings (the Great Bahama Bank, the Great Australian Bight, and the Great Barrier Reef), and two pelagic settings (the Walvis Ridge, and the Madingley Rise). These sites were selected in order to assess the influence of several different environmental factors including; sediment and organic matter producers, sediment mineralogy, margin architecture, sea level oscillations, and sediment transport pathways. In the three periplatform settings, multiple cores arranged in a margin to basin transect were analyzed in order to provide insights into the effects of downslope sediment transport. The preliminary results of this study suggest that sea level oscillations and margin architecture may artificially generate a covarying relationship in periplatform sediments that is unrelated to changes in the global carbon cycle. Furthermore, preliminary results from the Walvis Ridge and the Madingley Rise sediments suggest that the relationship between inorganic and organic δ13C records may not always exhibit a positive covariance as is currently assumed for pelagic carbonates.

Skeletal manifestations of juvenile hypothyroidism and the impact of treatment on skeletal system

Directory of Open Access Journals (Sweden)

Manish Gutch

2013-01-01

Full Text Available Thyroid hormone mediates growth and development of the skeleton through its direct effects and through its permissive effects on growth hormone. The effect of hypothyroidism on bone is well described in congenital hypothyroidism, but the impact of thyroid hormone deficiency on a growing skeleton, as it happens with juvenile hypothyroidism, is less defined. In addition, the extent to which the skeletal defects of juvenile hypothyroidism revert on the replacement of thyroid hormone is not known. A study was undertaken in 29 juvenile autoimmune hypothyroid patients to study the skeletal manifestations of juvenile hypothyroidism and the impact of treatment of hypothyroidism on the skeletal system of juvenile patients. Hypothyroidism has a profound impact on the skeletal system and delayed bone age, dwarfism, and thickened bands at the metaphyseal ends being the most common findings. Post treatment, skeletal findings like delayed bone age and dwarfism improved significantly, but there were no significant changes in enlargement of sella, presence of wormian bones, epihyseal dysgenesis, vertebral changes and thickened band at the metaphyseal ends. With the treatment of hypothyroidism, there is an exuberant advancement of bone age, the catch up of bone age being approximately double of the chronological age advancement.

Skeletal muscle and fetal alcohol spectrum disorder.

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Myrie, Semone B; Pinder, Mark A

2018-04-01

Skeletal muscle is critical for mobility and many metabolic functions integral to survival and long-term health. Alcohol can affect skeletal muscle physiology and metabolism, which will have immediate and long-term consequences on health. While skeletal muscle abnormalities, including morphological, biochemical, and functional impairments, are well-documented in adults that excessively consume alcohol, there is a scarcity of information about the skeletal muscle in the offspring prenatally exposed to alcohol ("prenatal alcohol exposure"; PAE). This minireview examines the available studies addressing skeletal muscle abnormalities due to PAE. Growth restriction, fetal alcohol myopathy, and abnormalities in the neuromuscular system, which contribute to deficits in locomotion, are some direct, immediate consequences of PAE on skeletal muscle morphology and function. Long-term health consequences of PAE-related skeletal abnormalities include impaired glucose metabolism in the skeletal muscle, resulting in glucose intolerance and insulin resistance, leading to an increased risk of type 2 diabetes. In general, there is limited information on the morphological, biochemical, and functional features of skeletal abnormalities in PAE offspring. There is a need to understand how PAE affects muscle growth and function at the cellular level during early development to improve the immediate and long-term health of offspring suffering from PAE.

Paraphyseal changes on bone-age studies predict risk of delayed radiation-associated skeletal complications following total body irradiation

International Nuclear Information System (INIS)

Kitazono Hammell, Mary T.; Edgar, J.C.; Jaramillo, Diego; Bunin, Nancy

2013-01-01

Children undergoing total body irradiation (TBI) often develop delayed skeletal complications. Bone-age studies in these children often reveal subtle paraphyseal changes including physeal widening, metaphyseal irregularity and paraphyseal exostoses. To investigate whether paraphyseal changes on a bone-age study following TBI indicate a predisposition toward developing other radiation-associated skeletal complications. We retrospectively reviewed medical records and bone-age studies of 77 children receiving TBI at our institution between 1995 and 2008 who had at least 2 years of clinical follow-up and one bone-age study after TBI. We graded bone-age studies according to the severity of paraphyseal changes. All documented skeletal complications following TBI were tabulated. Kendall's tau-b was used to examine associations between degree of paraphyseal change and development of a skeletal complication. Kendall's tau analyses showed that physeal widening and metaphyseal irregularity/sclerosis (tau = 0.87, P < 0.001) and paraphyseal exostoses (tau = 0.68, P < 0.001) seen on bone-age studies were significantly positively associated with the development of delayed skeletal complications following TBI. Thirty percent of children with no or mild paraphyseal changes developed a delayed skeletal complication, compared with 58% of children with moderate paraphyseal changes and 90% of children with severe paraphyseal changes. Paraphyseal changes identified on a bone-age study correlate positively with the development of delayed skeletal complications elsewhere in the skeleton following TBI. (orig.)

Maxillary distraction osteogenesis in cleft lip and palate patients with skeletal anchorage.

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Minami, Katsuhiro; Mori, Yoshihide; Tae-Geon, Kwon; Shimizu, Hidetaka; Ohtani, Miyuki; Yura, Yoshiaki

2007-03-01

Maxillary distraction osteogenesis with the rigid external distraction (RED) system has been used to treat cleft lip and palate (CLP) patients with severe maxillary hypoplasia. We introduce maxillary distraction osteogenesis for CLP patients with skeletal anchorage adapted on a stereolithographic model. Six maxillary deficiency CLP patients treated according to our CLP treatment protocol had undergone maxillary distraction osteogenesis. In all patients, computed tomography (CT) images were recorded preoperatively, and the data were transferred to a workstation. Three-dimensional skeletal structures were reconstructed with CT data sets, and a stereolithographic model was produced. On the stereolithographic model, miniplates were adapted to the surface of maxilla beside aperture piriforms. The operation performed involved a high Le Fort I osteotomy with pterygomaxillary disjunction. Miniplates were fixed to the maxillary segment with three or four screws and used for anchorage of the RED system. Retraction of the maxillary segment was initiated after 1 week. The accuracy of the stereolithographic models was enough to adapt the miniplates so that there was no need to readjust the plates during surgery. Postoperative cephalometric analysis showed that the direction of the retraction was almost parallel to the palatal plane, and dental compensation did not occur. We performed maxillary distraction osteogenesis with skeletal anchorage adapted on the stereolithographic models. Excellent esthetic outcome and skeletal advancement were achieved without dentoalveolar compensations.

The nuclear bomb carbon curve recorded in tree-rings and lake sediments near Taal Volcano, Central Philippines

Science.gov (United States)

Liou, M. S.; Li, H. C.; Huang, S. K.; Guan, B. T.

2017-12-01

Dendrochronologies built from precisely dated annual rings have shown to record the regional bomb pulse and the C-14 concentration variations caused by local events. In this study, we collected teak trees Tectona grandis near the Lake Taal, Central Philippines in 2011 for dendrochronological analysis and radiocarbon dating. The tree-ring sample contains 90 rings dated from 1922 to 2011. Currently, 28 selected subsamples have been measured by AMS 14C on bulk carbon with a few samples on holocellulose. The 14C results of the samples indicate that: 1) the results of AMS 14C dating between holocellulose and whole wood from the same ring are similar, so we select whole wood for AMS 14C dating. 2) The nuclear bomb 14C pulse was clearly recorded in the Tectona grandis growth rings. The Δ14C values rose dramatically in 1960 and reached a maximum of 692‰ in 1966. The magnitude and the peak year of the bomb curve in the Tectona grandis tree-ring record are comparable to other published tree-ring records in the tropical regions. 3) The Δ14C values suddenly dropped in 1950, 1964 and 1968, probably affected by CO2 gas releasing due to the Taal volcanic activities. Further study on the tree-ring 14C dating will allow us to evaluate the bomb pulse trends more precisely, and the volcanic activities of Pinatubo and Taal Volcanoes. The tree-ring Δ14C record not only confirms existence of the bomb curve in Taal Lake area, but also allows us compare to the Δ14C record in the lake sediment for chronological construction. A 120-cm gravity core, TLS-2, collected from Lake Taal in 2008, shows the nuclear bomb carbon curve in the TOC of the core. However, the magnitude of the nuclear bomb 14C pulse in the TOC of TLS-2 is much lower than that in the tree-ring records, due to mixing effect of different organic carbon sources, smoothing effect of 14CO2 in multiple years plant growths, local old CO2 emission from volcanic activity, degassing from the lake bottom, and industrial and city

Human skeletal muscle releases leptin in vivo

DEFF Research Database (Denmark)

Wolsk, Emil; Grøndahl, Thomas Sahl; Pedersen, Bente Klarlund

2012-01-01

Leptin is considered an adipokine, however, cultured myocytes have also been found to release leptin. Therefore, as proof-of-concept we investigated if human skeletal muscle synthesized leptin by measuring leptin in skeletal muscle biopsies. Following this, we quantified human skeletal muscle...... was unaltered. During saline infusion the adipose tissue release averaged 0.8 ± 0.3 ng min(-1) 100g tissue(-1) whereas skeletal muscle release was 0.5 ± 0.1 ng min(-1) 100g tissue(-1). In young healthy humans, skeletal muscle contribution to whole body leptin production could be substantial given the greater...

AMPK in skeletal muscle function and metabolism

DEFF Research Database (Denmark)

Kjøbsted, Rasmus; Hingst, Janne Rasmuss; Fentz, Joachim

2018-01-01

Skeletal muscle possesses a remarkable ability to adapt to various physiologic conditions. AMPK is a sensor of intracellular energy status that maintains energy stores by fine-tuning anabolic and catabolic pathways. AMPK's role as an energy sensor is particularly critical in tissues displaying...... highly changeable energy turnover. Due to the drastic changes in energy demand that occur between the resting and exercising state, skeletal muscle is one such tissue. Here, we review the complex regulation of AMPK in skeletal muscle and its consequences on metabolism (e.g., substrate uptake, oxidation......, and storage as well as mitochondrial function of skeletal muscle fibers). We focus on the role of AMPK in skeletal muscle during exercise and in exercise recovery. We also address adaptations to exercise training, including skeletal muscle plasticity, highlighting novel concepts and future perspectives...

Experimental Evidence that Abrasion of Carbonate Sand is a Significant Source of Carbonate Mud

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Trower, L.; Kivrak, L.; Lamb, M. P.; Fischer, W. W.

2017-12-01

Carbonate mud is a major sedimentary component of modern and ancient tropical carbonate environments, yet its enigmatic origin remains debated. Early views on the origin of carbonate mud considered the abrasion of carbonate sand during sediment transport as a possible mechanism. In recent decades, however, prevailing thought has generally settled on a binary explanation: 1) precipitation of aragonite needles within the water column, and 2) post-mortem dispersal of biological aragonite, in particular from algae, and perhaps aided by fish. To test these different hypotheses, we designed a model and a set of laboratory experiments to quantify the rates of mud production associated with sediment transport. We adapted a recent model of ooid abrasion rate to predict the rate of mud production by abrasion of carbonate sand as a function of grain size and sediment transport mode. This model predicts large mud production rates, ranging from 103 to 104 g CaCO3/m2/yr for typical grain sizes and transport conditions. These rate estimates are at least one order of magnitude more rapid than the 102 g CaCO3/m2/yr estimates for other mechanisms like algal biomineralization, indicating that abrasion could produce much larger mud fluxes per area as other mechanisms. We tested these estimates using wet abrasion mill experiments; these experiments generated mud through mechanical abrasion of both ooid and skeletal carbonate sand for grain sizes ranging from 250 µm to >1000 µm over a range of sediment transport modes. Experiments were run in artificial seawater, including a series of controls demonstrating that no mud was produced via homogenous nucleation and precipitation in the absence of sand. Our experimental rates match the model predictions well, although we observed small systematic differences in rates between abrasion ooid sand and skeletal carbonate sand that likely stems from innate differences in grain angularity. Electron microscopy of the experimental products revealed

Duration of the pubertal peak in skeletal Class I and Class III subjects.

Science.gov (United States)

Kuc-Michalska, Małgorzata; Baccetti, Tiziano

2010-01-01

To estimate and compare the duration of the pubertal growth peak in Class I and Class III subjects. The data examined consisted of pretreatment lateral cephalometric records of 218 skeletal Class I or Class III subjects (93 female and 125 male subjects) of white ancestry. The duration of the pubertal peak was calculated from the average chronological age intervals between stages CS3 and CS4 of the cervical vertebral maturation in Class I vs Class III groups (t-test). In skeletal Class I subjects, the pubertal peak had a mean duration of 11 months, whereas in Class III subjects it lasted 16 months. The average difference (5 months) was statistically significant (P < .001). The growth interval corresponding to the pubertal growth spurt (CS3-CS4) was longer in Class III subjects than in subjects with normal skeletal relationships; the larger increases in mandibular length during the pubertal peak reported in the literature for Class III subjects may be related to the longer duration of the pubertal peak.

Skeletal and dental changes induced by bionator in early treatment of class II

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Dirceu Barnabé Raveli

2016-09-01

Full Text Available The purpose was to investigate the amount of skeletal and dentoalveolar changes after early treatment of Class II, Division 1 malocclusion with bionator appliance in prepubertal growing patients. Forty Class II patients were divided in two groups. Treated group consisted of 20 subjects treated consecutively with bionator. Mean age at the start of treatment (T0 was 9.1 years, while it was 10.6 years at the end of treatment (T1. Mean treatment time was 17.7 months. Pretreatment and post-treatment cephalometric records of treated group were evaluated and compared with a control group consisted of 20 patients with untreated Class II malocclusion. Intergroup comparisons were performed using Student’s t-tests and chi-square test with Yates’ correction at a significance level of 5 per cent. Bionator appliance was effective in generating differential growth between the jaws. Cephalometric skeletal measurements ANB, WITS, Lafh, Co-A and dental L6-Mp, U1.Pp, IsIi, OB, OJ showed statistically significantly different from the control. Bionator induced more dentoalveolar changes than skeletal during treatment in prepubertal stage.

Latest Permian carbonate carbon isotope variability traces heterogeneous organic carbon accumulation and authigenic carbonate formation

Science.gov (United States)

Schobben, Martin; van de Velde, Sebastiaan; Gliwa, Jana; Leda, Lucyna; Korn, Dieter; Struck, Ulrich; Vinzenz Ullmann, Clemens; Hairapetian, Vachik; Ghaderi, Abbas; Korte, Christoph; Newton, Robert J.; Poulton, Simon W.; Wignall, Paul B.

2017-11-01

Bulk-carbonate carbon isotope ratios are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorganic carbon. However, bulk-carbonate rock is also prone to incorporate diagenetic signals. The aim of the present study is to disentangle primary trends from diagenetic signals in carbon isotope records which traverse the Permian-Triassic boundary in the marine carbonate-bearing sequences of Iran and South China. By pooling newly produced and published carbon isotope data, we confirm that a global first-order trend towards depleted values exists. However, a large amount of scatter is superimposed on this geochemical record. In addition, we observe a temporal trend in the amplitude of this residual δ13C variability, which is reproducible for the two studied regions. We suggest that (sub-)sea-floor microbial communities and their control on calcite nucleation and ambient porewater dissolved inorganic carbon δ13C pose a viable mechanism to induce bulk-rock δ13C variability. Numerical model calculations highlight that early diagenetic carbonate rock stabilization and linked carbon isotope alteration can be controlled by organic matter supply and subsequent microbial remineralization. A major biotic decline among Late Permian bottom-dwelling organisms facilitated a spatial increase in heterogeneous organic carbon accumulation. Combined with low marine sulfate, this resulted in varying degrees of carbon isotope overprinting. A simulated time series suggests that a 50 % increase in the spatial scatter of organic carbon relative to the average, in addition to an imposed increase in the likelihood of sampling cements formed by microbial calcite nucleation to 1 out of 10 samples, is sufficient to induce the observed signal of carbon

Latest Permian carbonate carbon isotope variability traces heterogeneous organic carbon accumulation and authigenic carbonate formation

Directory of Open Access Journals (Sweden)

M. Schobben

2017-11-01

Full Text Available Bulk-carbonate carbon isotope ratios are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorganic carbon. However, bulk-carbonate rock is also prone to incorporate diagenetic signals. The aim of the present study is to disentangle primary trends from diagenetic signals in carbon isotope records which traverse the Permian–Triassic boundary in the marine carbonate-bearing sequences of Iran and South China. By pooling newly produced and published carbon isotope data, we confirm that a global first-order trend towards depleted values exists. However, a large amount of scatter is superimposed on this geochemical record. In addition, we observe a temporal trend in the amplitude of this residual δ13C variability, which is reproducible for the two studied regions. We suggest that (sub-sea-floor microbial communities and their control on calcite nucleation and ambient porewater dissolved inorganic carbon δ13C pose a viable mechanism to induce bulk-rock δ13C variability. Numerical model calculations highlight that early diagenetic carbonate rock stabilization and linked carbon isotope alteration can be controlled by organic matter supply and subsequent microbial remineralization. A major biotic decline among Late Permian bottom-dwelling organisms facilitated a spatial increase in heterogeneous organic carbon accumulation. Combined with low marine sulfate, this resulted in varying degrees of carbon isotope overprinting. A simulated time series suggests that a 50 % increase in the spatial scatter of organic carbon relative to the average, in addition to an imposed increase in the likelihood of sampling cements formed by microbial calcite nucleation to 1 out of 10 samples, is sufficient to induce the

Skeletal Muscle Na+ Channel Disorders

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Dina eSimkin

2011-10-01

Full Text Available Five inherited human disorders affecting skeletal muscle contraction have been traced to mutations in the gene encoding the voltage-gated sodium channel Nav1.4. The main symptoms of these disorders are myotonia or periodic paralysis caused by changes in skeletal muscle fiber excitability. Symptoms of these disorders vary from mild or latent disease to incapacitating or even death in severe cases. As new human sodium channel mutations corresponding to disease states become discovered, the importance of understanding the role of the sodium channel in skeletal muscle function and disease state grows.

Radiographic correlation of dental and skeletal age: Third molar, an age indicator.

Science.gov (United States)

Suma, Gn; Rao, Balaji B; Annigeri, Rajeshwari G; Rao, Dayashankara Jk; Goel, Sumit

2011-01-01

Age estimation plays a great role in forensic investigations, orthodontic and surgical treatment planning, and tooth transplantation. Teeth offer an excellent material for age determination by stages of development below the age of 25 years and by secondary changes after the age of 25 years. Third molar is often not included for this purpose due to its notorious developmental patterns. The aim of this study was to evaluate the development of third molar anlage in relation to skeletal maturities and the chronological age. One hundred and fifty-six young individuals, 78 males and 78 females, were selected. The stages of development of all the third molars in every individual were determined from panoramic radiographs. The skeletal development was assessed using hand wrist radiographs. Data were analyzed statistically for mean value, standard deviation and the relationship between the recorded characteristics. A STRONG CORRELATION WAS FOUND BETWEEN THIRD MOLAR DEVELOPMENT AND SKELETAL MATURITY (IN MALES: r=0.88, Pthird molar and 0.89 for mandibular third molar, Page, developmental stages of third molars and maturation of epiphyses of hand. Any of the three parameters could be used for the assessment of other maturities.

Report writing in skeletal radiology

International Nuclear Information System (INIS)

Rowe, L.J.; Yochum, T.R.

1987-01-01

The formulation of reports in clinical practice is a standard method of documentation of a patient's history, examination findings, therapeutic regime, and prognosis, as well as other important features. In the practice of producing and interpreting diagnostic radiographs, report writing also serves a number of important roles, which include providing an accurate means of recording findings in instances of 1) medicolegal circumstances; 2) a standard for comparison with previous or later examinations; 3) a permanent record if the radiographs are lost or not immediately available for perusal; 4) communication with other practitioners and health professionals; and 5) expediating the treatment regime by providing a resume of important indications and contraindictions for therapy. In the radiological literature there is a distinct lack of material on report writing and very little as to what would be considered a standard style. Consequently, radiological reporting has increasingly become a subjective, personalized procedure, with each individual modifying the report according to previous training, experience, and needs. It is the purpose of this chapter to provide basic guidelines on the mechanisms of formulating adequate standardized reports in radiological examinations of the skeletal system

Redox Control of Skeletal Muscle Regeneration.

Science.gov (United States)

Le Moal, Emmeran; Pialoux, Vincent; Juban, Gaëtan; Groussard, Carole; Zouhal, Hassane; Chazaud, Bénédicte; Mounier, Rémi

2017-08-10

Skeletal muscle shows high plasticity in response to external demand. Moreover, adult skeletal muscle is capable of complete regeneration after injury, due to the properties of muscle stem cells (MuSCs), the satellite cells, which follow a tightly regulated myogenic program to generate both new myofibers and new MuSCs for further needs. Although reactive oxygen species (ROS) and reactive nitrogen species (RNS) have long been associated with skeletal muscle physiology, their implication in the cell and molecular processes at work during muscle regeneration is more recent. This review focuses on redox regulation during skeletal muscle regeneration. An overview of the basics of ROS/RNS and antioxidant chemistry and biology occurring in skeletal muscle is first provided. Then, the comprehensive knowledge on redox regulation of MuSCs and their surrounding cell partners (macrophages, endothelial cells) during skeletal muscle regeneration is presented in normal muscle and in specific physiological (exercise-induced muscle damage, aging) and pathological (muscular dystrophies) contexts. Recent advances in the comprehension of these processes has led to the development of therapeutic assays using antioxidant supplementation, which result in inconsistent efficiency, underlying the need for new tools that are aimed at precisely deciphering and targeting ROS networks. This review should provide an overall insight of the redox regulation of skeletal muscle regeneration while highlighting the limits of the use of nonspecific antioxidants to improve muscle function. Antioxid. Redox Signal. 27, 276-310.

A Model for Interpreting High-Tower CO2 Concentration Records for the Surface Carbon Balance Information

Science.gov (United States)

Chen, B.; Chen, J. M.; Higuchi, K.; Chan, D.; Shashkov, A.

2002-05-01

Atmospheric CO2 concentration measurements have been made by scientists of Meteorological Service of Canada on a 40 m tower for the last 10 years at 15 minute intervals over a mostly intact boreal forest near Fraserdale (50N, 81W), Ontario, Canada. The long time records of CO2 as well as basic meteorological variables provide a unique opportunity to investigate any potential changes in the ecosystem in terms of carbon balance. A model is needed to decipher the carbon cycle signals from the diurnal and seasonal variation patterns in the CO2 record. For this purpose, the Boreal Ecosystem Productivity Simulator (BEPS) is expanded to include a one-dimensional CO2 vertical transfer model involving the interaction between plant canopies and the atmosphere in the surface layer and the diurnal dynamics of the mixed layer. An analytical solution of the scalar transfer equation within the surface layer is found using an assumption that the diurnal oscillation of CO2 concentration at a given height is sinusoidal, which is suitable for the investigation of the changes in diurnal variation pattern over the 10 year period. The complex interactions between the daily cycle of the atmosphere and vegetation CO2 exchange and the daily evolution of mixed layer entrainment of CO2 determines the CO2 variation pattern at a given height. The expanded BEPS can simulate within ñ2 ppm the hourly CO2 records at the 40 m measurement height. The annual totals of gross primary productivity (GPP), net primary productivity (NPP) and net ecosystem productivity (NEP), summed up from the hourly results, agree within 5% of previous estimates of BEPS at daily steps, indicating the internal consistency of the hourly model. The model is therefore ready for exploring changes in the CO2 record as affected by changes in the forest ecosystems upwind of the tower. Preliminary results indicate that the diurnal variation amplitude of CO2 has increased by 10-20% over the 10 years period, and this change can

Effects of 45Ca on murine skeletal muscle. 2

International Nuclear Information System (INIS)

Asotra, K.; Katoch, S.S.; Krishan, K.; Malhotra, R.K.

1983-01-01

Swiss albino mice were injected intraperitoneally with 3.7x10 4 Bq and 7.4x10 4 Bq 45 Ca/g body weight. 45 Ca-treated mice were sacrificed on days 1, 3, 5, 7, 14 and 28 and activities of acid phosphatase, alkaline phosphatase and glucose 6-phosphatase bioassayed in diaphragm and gastrocnemius. Activities of acid and alkaline phosphatases decreased after the 1st day of 45 Ca treatment in both the muscles compared with the normal controls. These two enzymes apparently do not contribute to myofiber necrosis in irradiated skeletal muscle. Glucose 6-phosphatase levels increased in the two irradiated muscles and with 7.4x10 4 Bq 45 Ca dose as much as 20-fold and 7-fold elevations are recorded in diaphragm and gastrocnemius, respectively, indicating a radiation-induced stimulation of inhibition of glucose 6-phosphatase channelization for energy generation. The possible role of elevated glucose 6-phosphatase levels in glycogen accumulation on account of radiations in skeletal muscle has been discussed. (author)

Optical versus radiographic magnification for fine-detail skeletal radiography

International Nuclear Information System (INIS)

Genant, H.K.; Doi, K.; Mall, J.C.

1974-01-01

Fine detail radiographic techniques for peripheral skeletal imaging have gained wide clinical acceptance. In this study, the imaging properties and clinical applications of the optical magnification technique, which employs fine-grain industrial film and a large focal spot, have been compared quantitatively and qualitatively with those of three slow screen-film techniques, namely, contact exposure with a large focal spot, 2X radiographic magnification with a 0.3 mm focal spot, and 4X radiographic magnification with a 50 μ focal spot. The modulation transfer functions (MTFs) of the recording systems and focal spots have been obtained and film sensitometry has been performed. Clinical comparisons for patients with metabolic, arthritic, and neoplastic skeletal disorders have been made. The results illustrate the superiority of the optical magnification technique over contact or 2X magnification techniques using slow screen-film systems. If a microfocus tube is used, however, direct radiographic magnification may provide images comparable in resolution, noise, and contrast to those made with the optical magnification technique, and at lower radiation exposure to the patient. (U.S.)

Cerebellar medulloblastoma presenting with skeletal metastasis

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Barai Sukanta

2004-04-01

Full Text Available Medulloblastomas are highly malignant brain tumours, but only rarely produce skeletal metastases. No case of medulloblastoma has been documented to have produced skeletal metastases prior to craniotomy or shunt surgery. A 21-year-old male presented with pain in the hip and lower back with difficulty in walking of 3 months′ duration. Signs of cerebellar dysfunction were present hence a diagnosis of cerebellar neoplasm or skeletal tuberculosis with cerebellar abscess formation was considered. MRI of brain revealed a lesion in the cerebellum suggestive of medulloblastoma. Bone scan revealed multiple sites of skeletal metastases excluding the lumbar vertebrae. MRI of lumbar spine and hip revealed metastases to all lumbar vertebrae and both hips. Computed tomography-guided biopsy was obtained from the L3 vertebra, which revealed metastatic deposits from medulloblastoma. Cerebrospinal fluid cytology showed the presence of medulloblastoma cells. A final diagnosis of cerebellar medulloblastoma with skeletal metastases was made. He underwent craniotomy and histopathology confirmed medulloblastoma.

Ultrasound guided needle biopsy of skeletal muscle in neuromuscular disease

DEFF Research Database (Denmark)

Lindequist, S; Schrøder, H D; Larsen, C

1990-01-01

Guided by ultrasonography percutaneous needle biopsy of skeletal muscle was performed in 24 patients, using the one hand held Biopty system and a 2 mm Tru-Cut needle. The specimens were graded with regard to diagnostic quality and utility and almost all specimens (96%) were of highest quality. Th....... The use of ultrasonography was helpful in selecting a suitable area for the biopsy and vascular structures could be avoided. The procedure was well tolerated and easy to perform, and no complications were recorded....

Spot light on skeletal muscles: optogenetic stimulation to understand and restore skeletal muscle function.

Science.gov (United States)

van Bremen, Tobias; Send, Thorsten; Sasse, Philipp; Bruegmann, Tobias

2017-08-01

Damage of peripheral nerves results in paralysis of skeletal muscle. Currently, the only treatment option to restore proper function is electrical stimulation of the innervating nerve or of the skeletal muscles directly. However this approach has low spatial and temporal precision leading to co-activation of antagonistic muscles and lacks cell-type selectivity resulting in pain or discomfort by stimulation of sensible nerves. In contrast to electrical stimulation, optogenetic methods enable spatially confined and cell-type selective stimulation of cells expressing the light sensitive channel Channelrhodopsin-2 with precise temporal control over the membrane potential. Herein we summarize the current knowledge about the use of this technology to control skeletal muscle function with the focus on the direct, non-neuronal stimulation of muscle fibers. The high temporal flexibility of using light pulses allows new stimulation patterns to investigate skeletal muscle physiology. Furthermore, the high spatial precision of focused illumination was shown to be beneficial for selective stimulation of distinct nearby muscle groups. Finally, the cell-type specific expression of the light-sensitive effector proteins in muscle fibers will allow pain-free stimulation and open new options for clinical treatments. Therefore, we believe that direct optogenetic stimulation of skeletal muscles is a very potent method for basic scientists that also harbors several distinct advantages over electrical stimulation to be considered for clinical use in the future.

Traumatic skeletal changes

International Nuclear Information System (INIS)

Troeger, J.; Schofer, O.

1985-01-01

Skeleton scintiscanning is indicated in the following cases: (1) Suspected bone injury after clinical examination, the radiograph of the skeletal region in question contributing findings that either do not confirm suspision, or make not clear whether the changes observed are traumatic. (2) Polytrauma. (3) When the accident scenario reported by the persons taking care of the child does not sufficiently explain the skeletal changes observed, or when these persons expressly deny the possibility of a trauma being the cause of findings observed. (4) Suspected or proven battered-child syndrome. (orig./MG) [de

Skeletal sarcoidosis; Skelettsarkoidose

Energy Technology Data Exchange (ETDEWEB)

Freyschmidt, J. [Klinikum Bremen-Mitte, Beratungsstelle und Referenzzentrum fuer Osteoradiologie, Bremen (Germany); Freyschmidt, P. [Dermatologische Gemeinschaftspraxis, Schwalmstadt (Germany)

2016-10-15

Presentation of the etiology, pathology, clinical course, radiology and differential diagnostics of skeletal sarcoidosis. Noncaseating epithelioid cell granulomas can trigger solitary, multiple or disseminated osteolysis, reactive osteosclerosis and/or granulomatous synovitis. The incidence of sarcoidosis is 10-12 per 100,000 inhabitants per year. Skeletal involvement is approximately 14 %. Skeletal involvement occurs almost exclusively in the stage of lymph node and pulmonary manifestation. Most cases of skeletal involvement are clinically asymptomatic. In the case of synovial involvement, unspecific joint complaints (arthralgia) or less commonly arthritis can occur. Typical skin alterations can be diagnostically significant. Punch out lesions osteolysis, coarse destruction and osteosclerosis can occur, which are best visualized with projection radiography and/or computed tomography. Pure bone marrow foci without interaction with the bone can only be detected with magnetic resonance imaging (MRI) and more recently with positron emission tomography (PET), mostly as incidental findings. There is a predeliction for the hand and trunk skeleton. Skeletal tuberculosis, metastases, multiple myeloma, Langerhans cell histiocytosis and sarcoid-like reactions in solid tumors must be differentiated. The key factors for correct diagnosis are thorax radiography, thorax CT and dermatological manifestations. (orig.) [German] Darstellung von Aetiologie, Pathologie, Klinik, Radiologie und Differenzialdiagnose der Skelettsarkoidose. Nichtverkaesende Epitheloidzellgranulome koennen solitaere, multiple oder disseminierte Osteolysen, reaktive Osteosklerosen und/oder eine granulomatoese Synovialitis ausloesen. Inzidenz der Sarkoidose: 10-12/100.000 Einwohner/Jahr. Skelettbeteiligung ca. 14 %. Skelettbeteiligungen kommen fast ausschliesslich im Stadium einer Lymphknoten- und pulmonalen Manifestation vor. Die meisten Skelettbeteiligungen verlaufen klinisch stumm. Bei synovialer

Pelvic radiograph in skeletal dysplasias: An approach

Directory of Open Access Journals (Sweden)

Manisha Jana

2017-01-01

Full Text Available The bony pelvis is constituted by the ilium, ischium, pubis, and sacrum. The pelvic radiograph is an important component of the skeletal survey performed in suspected skeletal dysplasia. Most of the common skeletal dysplasias have either minor or major radiological abnormalities; hence, knowledge of the normal radiological appearance of bony pelvis is vital for recognizing the early signs of various skeletal dysplasias. This article discusses many common and some uncommon radiological findings on pelvic radiographs along with the specific dysplasia in which they are seen; common differential diagnostic considerations are also discussed.

Lateglacial and Holocene climatic changes in south-eastern Patagonia inferred from carbonate isotope records of Laguna Potrok Aike (Argentina)

Science.gov (United States)

Oehlerich, M.; Mayr, C.; Gussone, N.; Hahn, A.; Hölzl, S.; Lücke, A.; Ohlendorf, C.; Rummel, S.; Teichert, B. M. A.; Zolitschka, B.

2015-04-01

First results of strontium, calcium, carbon and oxygen isotope analyses of bulk carbonates from a 106 m long sediment record of Laguna Potrok Aike, located in southern Patagonia are presented. Morphological and isotopic investigations of μm-sized carbonate crystals in the sediment reveal an endogenic origin for the entire Holocene. During this time period the calcium carbonate record of Laguna Potrok Aike turned out to be most likely ikaite-derived. As ikaite precipitation in nature has only been observed in a narrow temperature window between 0 and 7 °C, the respective carbonate oxygen isotope ratios serve as a proxy of hydrological variations rather than of palaeotemperatures. We suggest that oxygen isotope ratios are sensitive to changes of the lake water balance induced by intensity variations of the Southern Hemisphere Westerlies and discuss the role of this wind belt as a driver for climate change in southern South America. In combination with other proxy records the evolution of westerly wind intensities is reconstructed. Our data suggest that weak SHW prevailed during the Lateglacial and the early Holocene, interrupted by an interval with strengthened Westerlies between 13.4 and 11.3 ka cal BP. Wind strength increased at 9.2 ka cal BP and significantly intensified until 7.0 ka cal BP. Subsequently, the wind intensity diminished and stabilised to conditions similar to present day after a period of reduced evaporation during the "Little Ice Age". Strontium isotopes (87Sr/86Sr ratio) were identified as a potential lake-level indicator and point to a lowering from overflow conditions during the Glacial (∼17 ka cal BP) to lowest lake levels around 8 ka cal BP. Thereafter the strontium isotope curve resembles the lake-level curve which is stepwise rising until the "Little Ice Age". The variability of the Ca isotope composition of the sediment reflects changes in the Ca budget of the lake, indicating higher degrees of Ca utilisation during the period with

Voltage clamp methods for the study of membrane currents and SR Ca2+ release in adult skeletal muscle fibres

Science.gov (United States)

Hernández-Ochoa, Erick O.; Schneider, Martin F.

2012-01-01

Skeletal muscle excitation-contraction (E-C)1 coupling is a process composed of multiple sequential stages, by which an action potential triggers sarcoplasmic reticulum (SR)2 Ca2+ release and subsequent contractile activation. The various steps in the E-C coupling process in skeletal muscle can be studied using different techniques. The simultaneous recordings of sarcolemmal electrical signals and the accompanying elevation in myoplasmic Ca2+, due to depolarization-initiated SR Ca2+ release in skeletal muscle fibres, have been useful to obtain a better understanding of muscle function. In studying the origin and mechanism of voltage dependency of E-C coupling a variety of different techniques have been used to control the voltage in adult skeletal fibres. Pioneering work in muscles isolated from amphibians or crustaceans used microelectrodes or ‘high resistance gap’ techniques to manipulate the voltage in the muscle fibres. The development of the patch clamp technique and its variant, the whole-cell clamp configuration that facilitates the manipulation of the intracellular environment, allowed the use of the voltage clamp techniques in different cell types, including skeletal muscle fibres. The aim of this article is to present an historical perspective of the voltage clamp methods used to study skeletal muscle E-C coupling as well as to describe the current status of using the whole-cell patch clamp technique in studies in which the electrical and Ca2+ signalling properties of mouse skeletal muscle membranes are being investigated. PMID:22306655

Radiopharmaceutical agents for skeletal scanning

International Nuclear Information System (INIS)

Jansen, S.E.; Van Aswegen, A.; Loetter, M.G.; Minnaar, P.C.; Otto, A.C.; Goedhals, L.; Dedekind, P.S.

1987-01-01

The quality of bone scan images obtained with a locally produced and with an imported radiopharmaceutical bone agent, methylene diphosphonate (MDP), was compared visually. Standard skeletal imaging was carried out on 10 patients using both agents, with a period of 2 to 7 days between studies with alternate agents. Equal amounts of activity were administered for both agents. All images were acquired on Polaroid film for subsequent evaluation. The acquisition time for standard amount of counts per study was recorded. Three physicians with applicable experience evaluated image quality (on a 4 point scale) and detectability of metastasis (on a 3 point scale). There was no statistically significant difference (p 0,05) between the two agents by paired t-test of Hotelling's T 2 analysis. It is concluded that the imaging properties of the locally produced and the imported MDP are similar

Assessment of mandibular growth by skeletal scintigraphy

International Nuclear Information System (INIS)

Kaban, L.B.; Cisneros, G.J.; Heyman, S.; Treves, S.

1982-01-01

Accurate assessment of facial skeletal growth remains a major problem in craniomaxillofacial surgery. Current methods include: (1) comparisons of chronologic age with growth histories of the patient and the family, (2) hand-wrist radiographs compared with a standard, and (3) serial cephalometric radiographs. Uptake of technetium-99m methylene diphosphonate into bone is a reflection of current metabolic activity and blood flow. Therefore, scintigraphy with this radiopharmaceutical might serve as a good method of assessing skeletal growth. Thirty-four patients, ranging in age from 15 months to 22 years, who were undergoing skeletal scintigrams for acute pathologic conditions of the extremities, were used to develop standards of uptake based on age and skeletal maturation. The results indicate that skeletal scintigraphy may be useful in evaluation of mandibular growth

13C trend in an Egyptian recent tree as a record for global carbon dioxide behaviour

International Nuclear Information System (INIS)

Aly, A.I.M.; Belacy, N.; Abou El-Nour, F.

1988-01-01

The record of the 13 C content in tree rings of an Egyptian tree is used as indication for the increase of the atmospheric carbon dioxide concentration. A decrease of the 13 C isotopic content of the tree rings is observed starting from 1940 coinciding with a significant increase in the global production of CO 2 due to combustion of fossil fuel depleted in 13 C with respect to the atmosphere. Considering the local as well as the global CO 2 production rates together with the measured isotopic data, it may be concluded that the behaviour of carbon dioxide in the investigated Eastern Delta province in Egypt reflects mainly a global rather than a local effect. (author)

Skeletal muscle lymphoma: observations at MR imaging

International Nuclear Information System (INIS)

Eustace, S.; Winalski, C.S.; McGowen, A.; Lan, H.; Dorfman, D.

1996-01-01

We present the MR appearances of three patients with biopsy-proven primary lymphoma of skeletal muscle. In each case lymphoma resulted in bulky expansion of the involved muscle, homogeneously isointense to skeletal muscle on T1-weighted images, homogeneously hyperintense to skeletal muscle on T2-weighted images and diffusely enhancing following intravenous administration of gadopentate dimeglumine. (orig.)

MALDI imaging mass spectrometry: discrimination of pathophysiological regions in traumatized skeletal muscle by characteristic peptide signatures.

Science.gov (United States)

Klein, Oliver; Strohschein, Kristin; Nebrich, Grit; Oetjen, Janina; Trede, Dennis; Thiele, Herbert; Alexandrov, Theodore; Giavalisco, Patrick; Duda, Georg N; von Roth, Philipp; Geissler, Sven; Klose, Joachim; Winkler, Tobias

2014-10-01

Due to formation of fibrosis and the loss of contractile muscle tissue, severe muscle injuries often result in insufficient healing marked by a significant reduction of muscle force and motor activity. Our previous studies demonstrated that the local transplantation of mesenchymal stromal cells into an injured skeletal muscle of the rat improves the functional outcome of the healing process. Since, due to the lack of sufficient markers, the accurate discrimination of pathophysiological regions in injured skeletal muscle is inadequate, underlying mechanisms of the beneficial effects of mesenchymal stromal cell transplantation on primary trauma and trauma adjacent muscle area remain elusive. For discrimination of these pathophysiological regions, formalin-fixed injured skeletal muscle tissue was analyzed by MALDI imaging MS. By using two computational evaluation strategies, a supervised approach (ClinProTools) and unsupervised segmentation (SCiLS Lab), characteristic m/z species could be assigned to primary trauma and trauma adjacent muscle regions. Using "bottom-up" MS for protein identification and validation of results by immunohistochemistry, we could identify two proteins, skeletal muscle alpha actin and carbonic anhydrase III, which discriminate between the secondary damage on adjacent tissue and the primary traumatized muscle area. Our results underscore the high potential of MALDI imaging MS to describe the spatial characteristics of pathophysiological changes in muscle. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Skeletal muscle contraction-induced vasodilation in the microcirculation.

Science.gov (United States)

Hong, Kwang-Seok; Kim, Kijeong

2017-10-01

Maximal whole body exercise leads skeletal muscle blood flow to markedly increase to match metabolic demands, a phenomenon termed exercise hyperaemia that is accomplished by increasing vasodilation. However, local vasodilatory mechanisms in response to skeletal muscle contraction remain uncertain. This review highlights metabolic vasodilators released from contracting skeletal muscle, endothelium, or blood cells. As a considerable skeletal muscle vasodilation potentially results in hypotension, sympathetic nerve activity needs to be augmented to elevate cardiac output and blood pressure during dynamic exercise. However, since the enhanced sympathetic vasoconstriction restrains skeletal muscle blood flow, intramuscular arteries have an indispensable ability to blunt sympathetic activity for exercise hyperaemia. In addition, we discuss that mechanical compression of the intramuscular vasculature contributes to causing the initial phase of increasing vasodilation following a single muscle contraction. We have also chosen to focus on conducted (or ascending) electrical signals that evoke vasodilation of proximal feed arteries to elevate blood flow in the microcirculation of skeletal muscle. Endothelial hyperpolarization originating within distal arterioles ascends into the proximal feed arteries, thereby increasing total blood flow in contracting skeletal muscle. This brief review summarizes molecular mechanisms underlying the regulation of skeletal muscle blood flow to a single or sustained muscle contraction.

Forecasting the timing of peak mandibular growth in males by using skeletal age.

Science.gov (United States)

Hunter, W Stuart; Baumrind, Sheldon; Popovich, Frank; Jorgensen, Gertrud

2007-03-01

It is generally believed that the orthodontic treatment of a patient with a Class II malocclusion and a small mandible is enhanced by good growth at puberty, so that the timing of peak mandibular growth at puberty becomes of interest. To test the belief that skeletal age, whether early, average, or late, can be used to predict the timing of maximum growth of the mandible, whether early, average, or late, the predictive relationship between skeletal age and peak mandibular growth velocity (PMdV) at puberty was evaluated in 94 boys by using their longitudinal records from 4 to 18 years of age. Skeletal age was determined for each subject at ages 9 through 14 by using the method of Greulich and Pyle. At age 9, the Greulich and Pyle measurements predicted that 30 of the 94 subjects would have delayed PMdV equal to or exceeding 1 SD (of the mean age for PMdV), and 10 would have advanced PMdV equal to or exceeding 1 SD. When the actual age of PMdV was determined retrospectively from plots of annual mandibular growth increments, it was found that only 4 of the 30 in the delayed group had actually experienced delays in PMdV, and only 2 of the 10 in the advanced group had experienced accelerated PMdV. Skeletal age is not a reliable predictor of the timing of PMdV.

Nanometer-Scale Chemistry of a Calcite Biomineralization Template: Implications for Skeletal Composition and Nucleation

Energy Technology Data Exchange (ETDEWEB)

Branson, Oscar; Bonnin, Elisa A.; Perea, Daniel E.; Spero, Howard J.; Zhu, Zihua; Winters, Maria; Hönisch, Bärbel; Russell, Ann D.; Fehrenbacher, Jennifer S.; Gagnon, Alexander C.

2016-10-28

Biomineralizing organisms exhibit exquisite control over skeletal morphology and composition. The promise of understanding and harnessing this feat of natural engineering has motivated an intense search for the mechanisms that direct in vivo mineral self-assembly. We used atom probe tomography, a sub-nanometer 3D chemical mapping technique, to examine the chemistry of a buried organic-mineral interface in biomineral calcite from a marine foraminifer. The chemical patterns at this interface capture the processes of early biomineralization, when the shape, mineralogy, and orientation of skeletal growth are initially established. Sodium is enriched by a factor of nine on the organic side of the interface. Based on this pattern, we suggest that sodium plays an integral role in early biomineralization, potentially altering interfacial energy to promote crystal nucleation, and that interactions between organic surfaces and electrolytes other than calcium or carbonate could be a crucial aspect of CaCO3 biomineralization.

The skeletal endocannabinoid system: clinical and experimental insights.

Science.gov (United States)

Raphael, Bitya; Gabet, Yankel

2016-05-01

Recently, there has been a rapidly growing interest in the role of cannabinoids in the regulation of skeletal remodeling and bone mass, addressed in basic, translational and clinical research. Since the first publications in 2005, there are more than 1000 publications addressing the skeletal endocannabinoid system. This review focuses on the roles of the endocannabinoid system in skeletal biology via the cannabinoid receptors CB1, CB2 and others. Endocannabinoids play important roles in bone formation, bone resorption and skeletal growth, and are sometimes age, gender, species and strain dependent. Controversies in the literature and potential therapeutic approaches targeting the endocannabinoid system in skeletal disorders are also discussed.

Passive in vivo elastography from skeletal muscle noise

International Nuclear Information System (INIS)

Sabra, Karim G.; Conti, Stephane; Roux, Philippe; Kuperman, W. A.

2007-01-01

Measuring the in vivo elastic properties of muscles (e.g., stiffness) provides a means for diagnosing and monitoring muscular activity. The authors demonstrated a passive in vivo elastography technique without an active external radiation source. This technique instead uses cross correlations of contracting skeletal muscle noise recorded with skin-mounted sensors. Each passive sensor becomes a virtual in vivo shear wave source. The results point to a low-cost, noninvasive technique for monitoring biomechanical in vivo muscle properties. The efficacy of the passive elastography technique originates from the high density of cross paths between all sensor pairs, potentially achieving the same sensitivity obtained from active elastography methods

Skeletal shape correspondence via entropy minimization

Science.gov (United States)

Tu, Liyun; Styner, Martin; Vicory, Jared; Paniagua, Beatriz; Prieto, Juan Carlos; Yang, Dan; Pizer, Stephen M.

2015-03-01

Purpose: Improving the shape statistics of medical image objects by generating correspondence of interior skeletal points. Data: Synthetic objects and real world lateral ventricles segmented from MR images. Method(s): Each object's interior is modeled by a skeletal representation called the s-rep, which is a quadrilaterally sampled, folded 2-sided skeletal sheet with spoke vectors proceeding from the sheet to the boundary. The skeleton is divided into three parts: up-side, down-side and fold-curve. The spokes on each part are treated separately and, using spoke interpolation, are shifted along their skeletal parts in each training sample so as to tighten the probability distribution on those spokes' geometric properties while sampling the object interior regularly. As with the surface-based correspondence method of Cates et al., entropy is used to measure both the probability distribution tightness and sampling regularity. The spokes' geometric properties are skeletal position, spoke length and spoke direction. The properties used to measure the regularity are the volumetric subregions bounded by the spokes, their quadrilateral sub-area and edge lengths on the skeletal surface and on the boundary. Results: Evaluation on synthetic and real world lateral ventricles demonstrated improvement in the performance of statistics using the resulting probability distributions, as compared to methods based on boundary models. The evaluation measures used were generalization, specificity, and compactness. Conclusions: S-rep models with the proposed improved correspondence provide significantly enhanced statistics as compared to standard boundary models.

A comparative study of modern carbonate mud in reefs and carbonate platforms: Mostly biogenic, some precipitated

Science.gov (United States)

Gischler, Eberhard; Dietrich, Sarah; Harris, Daniel; Webster, Jody M.; Ginsburg, Robert N.

2013-06-01

Carbonate mud from reefs and carbonate platforms in six locations of the Atlantic, Indian, and Pacific Oceans (Belize, Bahamas, Florida, the Maldives, French Polynesia, Great Barrier Reef) was systematically and quantitatively analyzed with regard to texture, composition, mineralogy, and geochemistry. Mud composition shows considerable variability, however, the data supports the contention that these muds are largely derived from the breakdown of skeletal grains and codiacean algae. Only mud from the Bahamas and northern Belize, areas which are characterized by common whitings, is interpreted to be mainly inorganically precipitated. Three grain-size fractions (63-20 μm, 20-4 μm, aragonite needles, nanograins, and coccoliths. Coccoliths are common in deeper lagoonal settings of the open ocean settings (Maldives, French Polynesia). The geochemistry of the aragonite contents and strontium concentrations, suggesting physico-chemical precipitation. The northern Belize and Great Barrier Reef samples show the highest magnesium calcite values and, accordingly, produced the lowest aragonite and strontium measurements. The high-magnesium calcite portion of the northern Belize mud is either precipitated or due to abundant micritized skeletal grains (e.g., foraminifera): more studies are needed to verify the origin. In the case of the Great Barrier Reef sample, coralline algae appear to be the source of abundant high-magnesium calcite. This study emphasizes that from a global perspective, modern muds in reefs and carbonate platforms exhibit different compositions but are in many cases biologically derived. Even though the composition of modern carbonate muds varies among the six locations investigated, they may serve as analogs for the formation of muds in Cenozoic and Mesozoic reefs and carbonate platforms. Limitations of the interpretation of carbonate-mud origin include the difficulty of identifying, quantifying, and analyzing small grains, the ease with which small

[Molecular mechanisms of skeletal muscle hypertrophy].

Science.gov (United States)

Astratenkova, I V; Rogozkin, V A

2014-06-01

Enzymes Akt, AMPK, mTOR, S6K and PGC-1a coactivator take part in skeletal muscles in the regulation of synthesis of proteins. The expression of these proteins is regulated by growth factors, hormones, nutrients, mechanical loading and leads to an increase in muscle mass and skeletal muscle hypertrophy. The review presents the results of studies published in the past four years, which expand knowledge on the effects of various factors on protein synthesis in skeletal muscle. The attention is focused on the achievements that reveal and clarify the signaling pathways involved in the regulation of protein synthesis in skeletal muscle. The central place is taken by mTOR enzyme which controls and regulates the main stages of the cascade of reactions of muscle proteins providing synthesis in the conditions of human life. coactivator PGC-1a.

Archform comparisons between skeletal class II and III malocclusions.

Directory of Open Access Journals (Sweden)

Wei Zou

Full Text Available The purpose of this cross-sectional research was to explore the relationship of the mandibular dental and basal bone archforms between severe Skeletal Class II (SC2 and Skeletal Class III (SC3 malocclusions. We also compared intercanine and intermolar widths in these two malocclusion types. Thirty-three virtual pretreatment mandibular models (Skeletal Class III group and Thirty-five Skeletal Class II group pretreatment models were created with a laser scanning system. FA (the midpoint of the facial axis of the clinical crownand WALA points (the most prominent point on the soft-tissue ridgewere employed to produce dental and basal bone archforms, respectively. Gained scatter diagrams of the samples were processed by nonlinear regression analysis via SPSS 17.0. The mandibular dental and basal bone intercanine and intermolar widths were significantly greater in the Skeletal Class III group compared to the Skeletal Class II group. In both groups, a moderate correlation existed between dental and basal bone arch widths in the canine region, and a high correlation existed between dental and basal bone arch widths in the molar region. The coefficient of correlation of the Skeletal Class III group was greater than the Skeletal Class II group. Fourth degree, even order power functions were used as best-fit functions to fit the scatter plots. The radius of curvature was larger in Skeletal Class III malocclusions compared to Skeletal Class II malocclusions (rWALA3>rWALA2>rFA3>rFA2. In conclusion, mandibular dental and basal intercanine and intermolar widths were significantly different between the two groups. Compared with Skeletal Class II subjects, the mandibular archform was more flat for Skeletal Class III subjects.

Generalized skeletal pathology: Results of radionuclide studies

International Nuclear Information System (INIS)

Fueger, G.F.; Aigner, R.

1987-01-01

Generalized pathological changes may involve the skeleton systematically (bone tissue, bone marrow) or at multiple sites involving destruction or infiltration. Appropriate radionuclide studies include total-body bone or bone marrow scintigraphy, absorptiometry (osteodensitometry) and the 24 h whole-body retention measurement. Established radioindicators are 99m-Tc-(hydroxy)methylendiphosphonate (HMDP or MDP) and 99m-Tc-human serumalbumin-nanocolloid. Absorptiometry of the forearm, extended by computer-assisted transaxial tomography, may be expected to prove as the most efficient method of bone density measurement. The 24 h whole-body retention measurement is useful for the diagnosis and follow-up of metabolic and endocrine osteopathies, if the very same osteotropic 99m-Tc-chelate is used. Whole-body bone scintigraphy today is one of the most important radionuclide studies for diagnosis and follow-up of skeletal metastases. Scintigraphy provides evidence of skeletal metastases several months earlier than radiological examinations. In about 40 percent of patients with cancer of the prostate, scintigraphy provided positive findings of skeletal metastases in the absence of both pain and increased levels of phosphatase. In patients with a history of malignancy, 60 percent of solitary findings on skeletal scintigraphy are metastases. The frequency of false negative findings obtained by whole-body skeletal scintigraphy are metastases. The frequency of false negative findings obtained by whole-body skeletal scintigraphy ranges from 2 to 4%. Compared to skeletal scintigraphy, bone marrow scintigraphy frequently yields significant additional findings in cases of plasmocytoma, histiocytoma, lymphoma and haemoblastoses. (orig.) [de

Kinematic analysis of mandibular motion before and after orthognathic surgery for skeletal Class III malocclusion: A pilot study.

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Ugolini, Alessandro; Mapelli, Andrea; Segù, Marzia; Galante, Domenico; Sidequersky, Fernanda V; Sforza, Chiarella

2017-03-01

The aim of the study was to detect the changes in 3D mandibular motion after orthognathic surgery for skeletal Class III malocclusion. Using a 3D motion analyzer, free mandibular border movements were recorded in nine patients successfully treated for skeletal Class III malocclusion and in nine patients scheduled for orthognathic surgery. Data were compared using Mann-Whitney non-parametric U-test. The results showed no differences between the groups in the total amount of mouth opening, protrusion, and in lateral excursions, but the percentage of mandibular movement explained by condylar translation was significantly increased after surgery (20% vs. 23.6%). During opening, the post-surgery patients showed a more symmetrical mandibular interincisal point and condylar path than pre-surgery patients (p < 0.01). Patients treated with orthognathic surgery for skeletal Class III malocclusion recover a good and symmetric temporomandibular joint function.

Skeletal Stem Cells: Origins, Functions and Uncertainties.

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Mohamed, Fatma F; Franceschi, Renny T

2017-12-01

The development and maintenance of the skeleton requires a steady source of skeletal progenitors to provide the osteoblasts and chondrocytes necessary for bone and cartilage growth and development. The current model for skeletal stem cells (SSCs) posits that SSC/progenitor cells are present in bone marrow (BM) and other osteogenic sites such as cranial sutures where they undergo self-renewal and differentiation to give rise to the main skeletal tissues. SSCs hold great promise for understanding skeletal biology and genetic diseases of bone as well as for the advancement of bone tissue engineering and regenerative medicine strategies. In the past few years, a considerable effort has been devoted to identifying and purifying skeletal stem cells and determining their contribution to bone formation and homeostasis. Here, we review recent progress in this area with particular emphasis on the discovery of specific SSC markers, their use in tracking the progression of cell populations along specific lineages and the regulation of SSCs in both the appendicular and cranial skeleton.

Skeletal MR imaging: Correlation with skeletal scintigraphy

International Nuclear Information System (INIS)

Colletti, P.M.; Raval, J.K.; Ford, P.V.; Benson, R.C.; Kerr, R.M.; Boswell, W.D.; Siegel, M.E.; Ralls, P.W.

1987-01-01

Skeletal MR images bone marrow while skeletal scintigraphy uses bone metabolism to demonstrate abnormalities. The purpose of this paper is to correlate these MR and scintigraphic findings. T1 and T2 MR images at 0.5 T were correlated with planar bone scintigraphy (RN) using Tc-99m MDP in 56 patients. Of 23 cases with suspected spinal metastases, 19 were positive by MR imaging, 16 by RN. Individual lesions were shown better by MR imaging in five and by RN in two. These two cases had scoliosis, a potential difficulty with MR imaging. In 14 cases of suspected avascular necrosis (AVN), MR imaging was positive in 13 while RN was positive in ten. One negative case by RN had bilateral AVN by MR imaging. Four skull lesions shown easily by RN were seen only in retrospect on MR images. MR imaging is advantageous in evaluating bones with predominant marrow such as vertebrae or the femoral head, while RN is superior in areas primarily composed of cortical bone such as the skull

Pathogenesis of Insulin Resistance in Skeletal Muscle

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Muhammad A. Abdul-Ghani

2010-01-01

Full Text Available Insulin resistance in skeletal muscle is manifested by decreased insulin-stimulated glucose uptake and results from impaired insulin signaling and multiple post-receptor intracellular defects including impaired glucose transport, glucose phosphorylation, and reduced glucose oxidation and glycogen synthesis. Insulin resistance is a core defect in type 2 diabetes, it is also associated with obesity and the metabolic syndrome. Dysregulation of fatty acid metabolism plays a pivotal role in the pathogenesis of insulin resistance in skeletal muscle. Recent studies have reported a mitochondrial defect in oxidative phosphorylation in skeletal muscle in variety of insulin resistant states. In this review, we summarize the cellular and molecular defects that contribute to the development of insulin resistance in skeletal muscle.

Using n-alkane records to constrain carbon cycle - hydrological cycle coupling: Case study from the Northern Hemisphere mid-latitudes during the PETM

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Krishnan, S.; Pagani, M.; Tipple, B. J.

2010-12-01

The early Eocene was a warmer world compared to the present and is characterized by rising temperatures interspersed with rapid hyperthermal events. During the largest of these rapid warming events; the Paleocene-Eocene Thermal Maximum (PETM), proxy records suggest that sea surface temperatures (SST) rose by 3-5 deg. C in the tropics (Zachos et al., 2003, Tripati and Elderfield, 2004), >5 deg. C in the Arctic (Sluijs et al., 2006) and perhaps has high as 9 deg. C in some sub-Antarctic regions (Kennett and Stott, 1991; Thomas et al., 1999). This warming is believed to be the result of massive input of 13C-depleted carbon into the ocean-atmosphere system, evidenced by the large negative carbon isotope excursion (CIE) and carbonate dissolution associated with the event. However, there are several questions regarding the exact mechanism of warming and feedbacks between the carbon cycle and climate. Did climate shift prior to the main event that led to the release of isotopically light carbon? Do we observe consistent leads or lags between changes in carbon isotopes and hydrological conditions during warm intervals? This study aims to reconstruct hydrological changes in the in the Northern Hemisphere mid-latitudes during the PETM using terrestrial biomarkers. Terrestrial biomarkers, such leaf-wax lipids stored in sediments, have the unique advantage of recording carbon and hydrogen isotopic compositions of atmospheric CO2 (modified by plant fractionation) and precipitation (modified by plant fractionation and evapotranspiration), allowing evaluation of the relative timing of carbon and hydrogen isotopic (i.e., climate) shifts. In this study, we compile and present three mid-latitude PETM records from the Northern Hemisphere, i.e. Alamedilla (Spain), Cicogna and Forada (Italy). The Cicogna and Forada sections are located in the Belluno basin (~12 km apart). Preliminary results do not indicate any significant pre-excursion hydrogen isotope changes at Cicogna, while at

A new conceptual model of coral biomineralisation: hypoxia as the physiological driver of skeletal extension

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Wooldridge, S.

2013-05-01

That corals skeletons are built of aragonite crystals with taxonomy-linked ultrastructure has been well understood since the 19th century. Yet, the way by which corals control this crystallization process remains an unsolved question. Here, I outline a new conceptual model of coral biomineralisation that endeavours to relate known skeletal features with homeostatic functions beyond traditional growth (structural) determinants. In particular, I propose that the dominant physiological driver of skeletal extension is night-time hypoxia, which is exacerbated by the respiratory oxygen demands of the coral's algal symbionts (= zooxanthellae). The model thus provides a new narrative to explain the high growth rate of symbiotic corals, by equating skeletal deposition with the "work-rate" of the coral host needed to maintain a stable and beneficial symbiosis. In this way, coral skeletons are interpreted as a continuous (long-run) recording unit of the stability and functioning of the coral-algae endosymbiosis. After providing supportive evidence for the model across multiple scales of observation, I use coral core data from the Great Barrier Reef (Australia) to highlight the disturbed nature of the symbiosis in recent decades, but suggest that its onset is consistent with a trajectory that has been followed since at least the start of the 1900s. In concluding, I outline how the proposed capacity of cnidarians (which includes modern reef corals) to overcome the metabolic limitation of hypoxia via skeletogenesis also provides a new hypothesis to explain the sudden appearance in the fossil record of calcified skeletons at the Precambrian-Cambrian transition - and the ensuing rapid appearance of most major animal phyla.

Determinants of relative skeletal maturity in South African children.

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Hawley, Nicola L; Rousham, Emily K; Johnson, William; Norris, Shane A; Pettifor, John M; Cameron, Noël

2012-01-01

The variation of skeletal maturity about chronological age is a sensitive indicator of population health. Age appropriate or advanced skeletal maturity is a reflection of adequate environmental and social conditions, whereas delayed maturation suggests inadequate conditions for optimal development. There remains a paucity of data, however, to indicate which specific biological and environmental factors are associated with advancement or delay in skeletal maturity. The present study utilises longitudinal data from the South African Birth to Twenty (Bt20) study to indentify predictors of relative skeletal maturity (RSM) in early adolescence. A total of 244 black South African children (n=131 male) were included in this analysis. Skeletal maturity at age 9/10 years was assessed using the Tanner and Whitehouse III RUS technique. Longitudinal data on growth, socio-economic position and pubertal development were entered into sex-specific multivariable general linear regression models with relative skeletal maturity (skeletal age-chronological age) as the outcome. At 9/10 years of age males showed an average of 0.66 years delay in skeletal maturation relative to chronological age. Females showed an average of 1.00 year delay relative to chronological age. In males, being taller at 2 years (pdetermining the rate of skeletal maturation during childhood independently of current stature. Copyright © 2011 Elsevier Inc. All rights reserved.

Spectrum of musculo-skeletal disorders in sickle cell disease in Lagos, Nigeria

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Ogo Chidiebere N

2010-01-01

Full Text Available Abstract Background Sickle cell anemia (SCA is a common genetic disease in Nigeria. Past studies from West Africa focused on isolated aspects of its medical and surgical presentations. To the best of our knowledge, the musculo-skeletal presentations amongst Nigerians with SCA have not been documented in a single all encompassing study. This work aims to prospectively document the musculo-skeletal disease burden among SCA patients. Methods In a prospective study of 318 consecutive patients with genotype-confirmed SCA at the Lagos University Teaching Hospital (LUTH, the musculo-skeletal pathologies, anatomic sites, grade of disease, age at presentation and management outcome were recorded over a one-year period. Data obtained were analyzed using Epi-Info software version 6.0. Data are presented as frequencies (% and mean values (SD as appropriate. Results The HbSS genotype occurred in 296 (93.0%, while 22 (7.0% were HbSC. 100 (31.4% patients with average presenting haemoglobin concentration of 8.2 g/100 ml in the study group, presented with 131 musculo-skeletal pathologies in 118 anatomic sites. Osteomyelitis 31 (31% and septic arthritis 19 (19% were most commonly observed in children less than 10 years. Skin ulcers and avascular necrosis (AVN occurred predominantly in the older age groups, with frequencies of 13 (13.0% and 26 (26.0% respectively. 20 (71.5% of diagnosed cases of AVN presented with radiological grade 4 disease. The lower limbs were involved in 84 (71.1% of sites affected. Lesions involving the spine were rare 11 (0.9%. Multiple presentations occurred in 89 (28.0% of patients; 62 (69.7% of which were children below 10 years. Conclusions Musculo-skeletal complications are common features of sickle cell anaemia seen in 31.4%. Infectious aetiologies predominate with long bones and joints of lower limbs more commonly affected by osteomyelitis and septic arthritis. Healthcare providers managing SCA should be aware of the potential

Aberrant and alternative splicing in skeletal system disease.

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Fan, Xin; Tang, Liling

2013-10-01

The main function of skeletal system is to support the body and help movement. A variety of factors can lead to skeletal system disease, including age, exercise, and of course genetic makeup and expression. Pre-mRNA splicing plays a crucial role in gene expression, by creating multiple protein variants with different biological functions. The recent studies show that several skeletal system diseases are related to pre-mRNA splicing. This review focuses on the relationship between pre-mRNA splicing and skeletal system disease. On the one hand, splice site mutation that leads to aberrant splicing often causes genetic skeletal system disease, like COL1A1, SEDL and LRP5. On the other hand, alternative splicing without genomic mutation may generate some marker protein isoforms, for example, FN, VEGF and CD44. Therefore, understanding the relationship between pre-mRNA splicing and skeletal system disease will aid in uncovering the mechanism of disease and contribute to the future development of gene therapy. © 2013 Elsevier B.V. All rights reserved.

Peripheral endocannabinoids regulate skeletal muscle development and maintenance

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Dongjiao Zhao

2010-12-01

Full Text Available As a principal tissue responsible for insulin-mediated glucose uptake, skeletal muscle is important for whole-body health. The role of peripheral endocannabinoids as regulators of skeletal muscle metabolism has recently gained a lot of interest, as endocannabinoid system disorders could cause peripheral insulin resistance. We investigated the role of the peripheral endocannabinoid system in skeletal muscle development and maintenance. Cultures of C2C12 cells, primary satellite cells and mouse skeletal muscle single fibers were used as model systems for our studies. We found an increase in cannabinoid receptor type 1 (CB1 mRNA and endocannabinoid synthetic enzyme mRNA skeletal muscle cells during differentiation. We also found that activation of CB1 inhibited myoblast differentiation, expanded the number of satellite cells, and stimulated the fast-muscle oxidative phenotype. Our findings contribute to understanding of the role of the endocannabinoid system in skeletal muscle metabolism and muscle oxygen consumption, and also help to explain the effects of the peripheral endocannabinoid system on whole-body energy balance.

[Skeletal anchorage in the past, today and tomorrow].

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Melsen, Birte; Dalstra, Michel

2017-03-01

Skeletal anchorage was not introduced as an alternative to conventional anchorage modalities. The first skeletal anchorage was a ligature through a hole in the infrazygomatic crest. This was replaced by surgical screws and finally the TADs, which were optimized with respect to the material and morphology, were developed. A bracket-like head allows for the use of the mini-implant as indirect anchorage, but should not be a tool for lost control resulting from badly planned biomechanics or failing compliance. Skeletal anchorage should serve as an adjunct to correct biomechanics, to enable treatments that could not be performed prior to the introduction of skeletal anchorage. The aim of this study was to test the hypothesis that temporary anchorage mini-screws help maintain bone density, height and width of alveolar processes in the extraction sites, and thus prevent the thinning of the alveolar ridge usually observed. In adult patients with degenerated dentitions the application of skeletal anchorage can allow for the displacement of teeth where no anchorage units are present, but also for the redevelopment and maintenance of atrophic alveolar bone. The basis for the optimal use of skeletal anchorage is that the correct line of action for the desired tooth displacement is defined and the necessary force system constructed either with the skeletal anchorage as direct or as indirect anchorage. After a period, during which osseointegrated implants were used as anchorage for tooth movement and bone maintenance, it was accepted that the mini-implants could serve also as anchorage for skeletal displacements avoiding loading of teeth. © EDP Sciences, SFODF, 2017.

Knee radiography in the diagnosis of skeletal dysplasias

International Nuclear Information System (INIS)

Kwee, Thomas C.; Beek, Frederik J.A.; Nievelstein, Rutger A.J.; Beemer, Frits A.

2006-01-01

Flattening of the epiphyses of long bones is seen in several skeletal dysplasias and standardized measurements on a radiograph of the knee to detect skeletal dysplasias using this feature have been described. Since then only two other studies in which this method was used have been published, and both included only a small number of children and neither had a control group. In addition, the Dutch National Working Group on Skeletal Dysplasias began to have doubts about the reliability of the method. We therefore decided to re-evaluate its accuracy in a population of children with and without a skeletal dysplasia. To determine the diagnostic value of standardized measurements on conventional AP radiographs of the knee in children with a skeletal dysplasia. Subjects and methods: We measured the distal femoral metaphysis and epiphysis according to the published method on conventional AP radiographs of the knee in 45 healthy children and 52 children with a skeletal dysplasia. We compared graphically the height of the distal femoral epiphysis with its width and with the width of the femoral metaphysis. Receiver operating characteristic (ROC) curves were calculated for each group of children. All graphs showed a considerable overlap between children with a skeletal dysplasia and healthy children. The size of the area under the ROC curves for the different groups was small, varying between 0.567 and 0.653. This method does not discriminate between children with a skeletal dysplasia and healthy children. We therefore consider it to be of little diagnostic value. (orig.)

Mechanical modeling of skeletal muscle functioning

NARCIS (Netherlands)

van der Linden, B.J.J.J.

1998-01-01

For movement of body or body segments is combined effort needed of the central nervous system and the muscular-skeletal system. This thesis deals with the mechanical functioning of skeletal muscle. That muscles come in a large variety of geometries, suggest the existence of a relation between muscle

A unified anatomy ontology of the vertebrate skeletal system.

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Wasila M Dahdul

Full Text Available The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO, to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish and multispecies (teleost, amphibian vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages, and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO, Gene Ontology (GO, Uberon, and Cell Ontology (CL, and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity.

A unified anatomy ontology of the vertebrate skeletal system.

Science.gov (United States)

Dahdul, Wasila M; Balhoff, James P; Blackburn, David C; Diehl, Alexander D; Haendel, Melissa A; Hall, Brian K; Lapp, Hilmar; Lundberg, John G; Mungall, Christopher J; Ringwald, Martin; Segerdell, Erik; Van Slyke, Ceri E; Vickaryous, Matthew K; Westerfield, Monte; Mabee, Paula M

2012-01-01

The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO), to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish) and multispecies (teleost, amphibian) vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages), and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO), Gene Ontology (GO), Uberon, and Cell Ontology (CL), and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity.

A Unified Anatomy Ontology of the Vertebrate Skeletal System

Science.gov (United States)

Dahdul, Wasila M.; Balhoff, James P.; Blackburn, David C.; Diehl, Alexander D.; Haendel, Melissa A.; Hall, Brian K.; Lapp, Hilmar; Lundberg, John G.; Mungall, Christopher J.; Ringwald, Martin; Segerdell, Erik; Van Slyke, Ceri E.; Vickaryous, Matthew K.; Westerfield, Monte; Mabee, Paula M.

2012-01-01

The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO), to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish) and multispecies (teleost, amphibian) vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages), and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO), Gene Ontology (GO), Uberon, and Cell Ontology (CL), and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity. PMID:23251424

The duration of pubertal growth peak among three skeletal classes

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Waqar Jeelani

Full Text Available ABSTRACT Introduction: Pubertal growth peak is closely associated with a rapid increase in mandibular length and offers a wide range of therapeutic modifiability. Objective: The aim of the present study was to determine and compare the mean ages of onset and duration of pubertal growth peak among three skeletal classes. Methods: A retrospective cross-sectional study was conducted using lateral cephalograms of 230 subjects with growth potential (110 males, 120 females. Subjects were categorized into three classes (Class I = 81, Class II = 82, Class III = 67, according to the sagittal relationship established between the maxilla and the mandible. The cervical vertebral maturation stage was recorded by means of Baccetti's method. The mean ages at CS3 and CS4 and the CS3-CS4 age interval were compared between boys and girls and among three skeletal classes. Results: Pubertal growth peak occurred on average four months earlier in girls than boys (p = 0.050. The average duration of pubertal growth peak was 11 months in Class I, seven months in Class II and 17 months in Class III subjects. Interclass differences were highly significant (Cohen's d > 0.08. However, no significant difference was found in the timing of pubertal growth peak onset among three skeletal classes (p = 0.126 in boys, p = 0.262 in girls. Conclusions: Girls enter pubertal growth peak on average four months earlier than boys. Moreover, the duration of pubertal growth peak is on average four months shorter in Class II and six months longer in Class III subjects as compared to Class I subjects.

Omega-3 Fatty Acids and Skeletal Muscle Health

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Stewart Jeromson

2015-11-01

Full Text Available Skeletal muscle is a plastic tissue capable of adapting and mal-adapting to physical activity and diet. The response of skeletal muscle to adaptive stimuli, such as exercise, can be modified by the prior nutritional status of the muscle. The influence of nutrition on skeletal muscle has the potential to substantially impact physical function and whole body metabolism. Animal and cell based models show that omega-3 fatty acids, in particular those of marine origin, can influence skeletal muscle metabolism. Furthermore, recent human studies demonstrate that omega-3 fatty acids of marine origin can influence the exercise and nutritional response of skeletal muscle. These studies show that the prior omega-3 status influences not only the metabolic response of muscle to nutrition, but also the functional response to a period of exercise training. Omega-3 fatty acids of marine origin therefore have the potential to alter the trajectory of a number of human diseases including the physical decline associated with aging. We explore the potential molecular mechanisms by which omega-3 fatty acids may act in skeletal muscle, considering the n-3/n-6 ratio, inflammation and lipidomic remodelling as possible mechanisms of action. Finally, we suggest some avenues for further research to clarify how omega-3 fatty acids may be exerting their biological action in skeletal muscle.

Activation of the skeletal alpha-actin promoter during muscle regeneration.

Science.gov (United States)

Marsh, D R; Carson, J A; Stewart, L N; Booth, F W

1998-11-01

Little is known concerning promoter regulation of genes in regenerating skeletal muscles. In young rats, recovery of muscle mass and protein content is complete within 21 days. During the initial 5-10 days of regeneration, mRNA abundance for IGF-I, myogenin and MyoD have been shown to be dramatically increased. The skeletal alpha-actin promoter contains E box and serum response element (SRE) regulatory regions which are directly or indirectly activated by myogenin (or MyoD) and IGF-I proteins, respectively. We hypothesized that the skeletal alpha-actin promoter activity would increase during muscle regeneration, and that this induction would occur before muscle protein content returned to normal. Total protein content and the percentage content of skeletal alpha-actin protein was diminished at 4 and 8 days and re-accumulation had largely occurred by 16 days post-bupivacaine injection. Skeletal alpha-actin mRNA per whole muscle was decreased at day 8, and thereafter returned to control values. During regeneration at day 8, luciferase activity (a reporter of promoter activity) directed by -424 skeletal alpha-actin and -99 skeletal alpha-actin promoter constructs was increased by 700% and 250% respectively; however, at day 16, skeletal alpha-actin promoter activities were similar to control values. Thus, initial activation of the skeletal alpha-actin promoter is associated with regeneration of skeletal muscle, despite not being sustained during the later stages of regrowth. The proximal SRE of the skeletal alpha-actin promoter was not sufficient to confer a regeneration-induced promoter activation, despite increased serum response factor protein binding to this regulatory element in electrophoretic mobility shift assays. Skeletal alpha-actin promoter induction during regeneration is due to a combination of regulatory elements, at least including the SRE and E box.

Upon the triple phase skeletal scintigraphy in traumatology

International Nuclear Information System (INIS)

Spitz, W.

1988-01-01

A broadly established indication catalogue for skeletal scintigraphy in traumatology is resulting from about 1500 skeletal scans. Aside from the exclusion of any osseous lesion, from the differentiation of uncertain X-ray findings, from the determination of the extent of osseous lesions in polytraumatic conditions and from the assessment of the relative fracture age, the follow-up after trauma and therapeutical intervention, the demonstration of battered child syndromes and of soft tissue lesions are of special importance with regard to these topics. For all that, the high sensitivity of the 3-phase skeletal scintigraphy for every enhancement of osseous turnover represents the elementary prerequisite for the employment of this non-invasive technique as an ideal screening method in traumatological diagnostics. The experiences from the past years have resulted in an increased frequency of skeletal scintigraphic studies to a similarly high level, as it is already established in the majority of institutions with respect to oncological problems, In the development of efficient and cost favourable diagnostic strategies with only little burden to the patient, skeletal scintigraphy will in future play an important role within the palette of modern skeletal diagnostics in traumatology. (orig.) [de

Skeletal Muscle Cell Induction from Pluripotent Stem Cells

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Yusaku Kodaka

2017-01-01

Full Text Available Embryonic stem cells (ESCs and induced pluripotent stem cells (iPSCs have the potential to differentiate into various types of cells including skeletal muscle cells. The approach of converting ESCs/iPSCs into skeletal muscle cells offers hope for patients afflicted with the skeletal muscle diseases such as the Duchenne muscular dystrophy (DMD. Patient-derived iPSCs are an especially ideal cell source to obtain an unlimited number of myogenic cells that escape immune rejection after engraftment. Currently, there are several approaches to induce differentiation of ESCs and iPSCs to skeletal muscle. A key to the generation of skeletal muscle cells from ESCs/iPSCs is the mimicking of embryonic mesodermal induction followed by myogenic induction. Thus, current approaches of skeletal muscle cell induction of ESCs/iPSCs utilize techniques including overexpression of myogenic transcription factors such as MyoD or Pax3, using small molecules to induce mesodermal cells followed by myogenic progenitor cells, and utilizing epigenetic myogenic memory existing in muscle cell-derived iPSCs. This review summarizes the current methods used in myogenic differentiation and highlights areas of recent improvement.

Evaluating two-dimensional skeletal structure parameters using radiological bone morphometric analysis

International Nuclear Information System (INIS)

Asa, Kensuke; Sakurai, Takashi; Kashima, Isamu; Kumasaka, Satsuki

2005-01-01

The objectives of this study was to investigate the reliability of two-dimensional (2D) skeletal structure parameters obtained using radiological bone morphometric analysis. The 2D skeletal parameters in the regions of interest (ROIs) were measured on computed radiography (CR) images of first phalanges from racehorses, using radiological bone morphometric analysis. Cancellous bone blocks were made from the phalanges in the same position as the ROI determined on CR images. Three-dimensional (3D) trabecular parameters were measured using micro-computed tomography (μCT). The correlations between the 2D skeletal parameters and 3D trabecular parameters were evaluated in relation to the measured bone strength. The following 2D skeletal structure parameters were correlated with bone strength (r=0.61-0.69): skeletal perimeter (Sk.Pm), skeletal number (Sk.N), skeletal separation (Sk.Sp), skeletal spacing (Sk.Spac), fractal dimension (FD), and skeletal pattern factor (SkPf). The 3D trabecular structure parameters were closely correlated with bone strength (r=0.74-0.86). The 2D skeletal parameters Sk.N, Sk.Pm, FD, SkPf, and Sk.Spac were correlated with the 3D trabecular parameters (r=0.61-0.70). The 2D skeletal parameters obtained using radiological bone morphometric analysis may be useful indicators of trabecular strength. (author)

Skeletal muscle proteomic signature and metabolic impairment in pulmonary hypertension.

Science.gov (United States)

Malenfant, Simon; Potus, François; Fournier, Frédéric; Breuils-Bonnet, Sandra; Pflieger, Aude; Bourassa, Sylvie; Tremblay, Ève; Nehmé, Benjamin; Droit, Arnaud; Bonnet, Sébastien; Provencher, Steeve

2015-05-01

Exercise limitation comes from a close interaction between cardiovascular and skeletal muscle impairments. To better understand the implication of possible peripheral oxidative metabolism dysfunction, we studied the proteomic signature of skeletal muscle in pulmonary arterial hypertension (PAH). Eight idiopathic PAH patients and eight matched healthy sedentary subjects were evaluated for exercise capacity, skeletal muscle proteomic profile, metabolism, and mitochondrial function. Skeletal muscle proteins were extracted, and fractioned peptides were tagged using an iTRAQ protocol. Proteomic analyses have documented a total of 9 downregulated proteins in PAH skeletal muscles and 10 upregulated proteins compared to healthy subjects. Most of the downregulated proteins were related to mitochondrial structure and function. Focusing on skeletal muscle metabolism and mitochondrial health, PAH patients presented a decreased expression of oxidative enzymes (pyruvate dehydrogenase, p metabolism in PAH skeletal muscles. We provide evidences that impaired mitochondrial and metabolic functions found in the lungs and the right ventricle are also present in skeletal muscles of patients. • Proteomic and metabolic analysis show abnormal oxidative metabolism in PAH skeletal muscle. • EM of PAH patients reveals abnormal mitochondrial structure and distribution. • Abnormal mitochondrial health and function contribute to exercise impairments of PAH. • PAH may be considered a vascular affliction of heart and lungs with major impact on peripheral muscles.

Magnetic and Geochemical Records of Glacial Terminations, Weathering and Carbon Burial in the Southeastern South China Sea for the Last 800 kyr

Science.gov (United States)

Kandasamy, S.; Kao, S.; Hsu, S.; Lee, T.; Velasco, V. M.; Soon, W.; Chen, M.

2013-12-01

Rebuilding of past climate and oceanographic records from monsoon dominated Asia is of vital importance for understanding the causes and mechanisms of global and regional climate changes at orbital-millennial timescales. South China Sea (SCS) provides the best marine platform to investigate a number of paleoclimate and paleoceanographic problems on different timescales mainly because of high sedimentation rates, good preservation of microfossils and the location of SCS as a connector between the Western Pacific Warm Pool and the SE Asian monsoon. Here we investigate magnetic, geochemical and isotopic records from a piston core MD97-2142 rose from the southeastern SCS to understand the past glacial terminations, chemical weathering and carbon burial on orbital to millennial timescales for the last 800 kyr. Terrigenous content and Al/Ti ratio reveal higher terrigenous input during glacial periods and vice versa during interglacials. Proxies of chemical weathering reveal larger fluctuations between 150 and 500 kyr than that of the last 150 kyr. Records of C/N ratio and carbon isotope of total organic carbon (δ13CTOC) mimic each other with higher marine productivity during marine isotope stages (MIS) 8, 10 and 12. Enrichment factors of Mn and Mo (EF Mn and EF Mo) show roughly an opposite pattern with 1 in most odd MIS, whereas <~1 EF Mn was evident in even MIS, suggesting that the former condition was likely attributed to bottom water ventilation associated with high sea levels during interglacials. We found through two endmember mixing model of δ13CTOC that lower burial of terrigenous fraction of TOC (OCTERR) during glacial intervals (MIS 6, 8, 10 and 12), but vice versa during interglacial (MIS 7, 9 and 11) periods. Our bulk magnetic susceptibility (MS) time series documents the last seven glacial terminations (T1-T7) with distinctive behaviors of T4 and T6. Wavelet analysis of MS record exhibits statistically significant periodicity at 239 kyr, 142 kyr, 85 kyr, 45

Measurement of skeletal muscle collagen breakdown by microdialysis

DEFF Research Database (Denmark)

Miller, B F; Ellis, D; Robinson, M M

2011-01-01

Exercise increases the synthesis of collagen in the extracellular matrix of skeletal muscle. Breakdown of skeletal muscle collagen has not yet been determined because of technical limitations. The purpose of the present study was to use local sampling to determine skeletal muscle collagen breakdown...... collagen breakdown 17–21 h post-exercise, and our measurement of OHP using GC–MS was in agreement with traditional assays....

A metabolic link to skeletal muscle wasting and regeneration

Directory of Open Access Journals (Sweden)

René eKoopman

2014-02-01

Full Text Available Due to its essential role in movement, insulating the internal organs, generating heat to maintain core body temperature, and acting as a major energy storage depot, any impairment to skeletal muscle structure and function may lead to an increase in both morbidity and mortality. In the context of skeletal muscle, altered metabolism is directly associated with numerous pathologies and disorders, including diabetes, and obesity, while many skeletal muscle pathologies have secondary changes in metabolism, including cancer cachexia, sarcopenia and the muscular dystrophies. Furthermore, the importance of cellular metabolism in the regulation of skeletal muscle stem cells is beginning to receive significant attention. Thus, it is clear that skeletal muscle metabolism is intricately linked to the regulation of skeletal muscle mass and regeneration. The aim of this review is to discuss some of the recent findings linking a change in metabolism to changes in skeletal muscle mass, as well as describing some of the recent studies in developmental, cancer and stem-cell biology that have identified a role for cellular metabolism in the regulation of stem cell function, a process termed ‘metabolic reprogramming’.

Disease-Induced Skeletal Muscle Atrophy and Fatigue

NARCIS (Netherlands)

Powers, Scott K.; Lynch, Gordon S.; Murphy, Kate T.; Reid, Michael B.; Zijdewind, Inge

2016-01-01

Numerous health problems including acute critical illness, cancer, diseases associated with chronic inflammation, and neurological disorders often result in skeletal muscle weakness and fatigue. Disease-related muscle atrophy and fatigue is an important clinical problem because acquired skeletal

Expanding the phenome and variome of skeletal dysplasia.

Science.gov (United States)

Maddirevula, Sateesh; Alsahli, Saud; Alhabeeb, Lamees; Patel, Nisha; Alzahrani, Fatema; Shamseldin, Hanan E; Anazi, Shams; Ewida, Nour; Alsaif, Hessa S; Mohamed, Jawahir Y; Alazami, Anas M; Ibrahim, Niema; Abdulwahab, Firdous; Hashem, Mais; Abouelhoda, Mohamed; Monies, Dorota; Al Tassan, Nada; Alshammari, Muneera; Alsagheir, Afaf; Seidahmed, Mohammed Zain; Sogati, Samira; Aglan, Mona S; Hamad, Muddathir H; Salih, Mustafa A; Hamed, Ahlam A; Alhashmi, Nadia; Nabil, Amira; Alfadli, Fatima; Abdel-Salam, Ghada M H; Alkuraya, Hisham; Peitee, Winnie Ong; Keng, W T; Qasem, Abdullah; Mushiba, Aziza M; Zaki, Maha S; Fassad, Mahmoud R; Alfadhel, Majid; Alexander, Saji; Sabr, Yasser; Temtamy, Samia; Ekbote, Alka V; Ismail, Samira; Hosny, Gamal Ahmed; Otaify, Ghada A; Amr, Khalda; Al Tala, Saeed; Khan, Arif O; Rizk, Tamer; Alaqeel, Aida; Alsiddiky, Abdulmonem; Singh, Ankur; Kapoor, Seema; Alhashem, Amal; Faqeih, Eissa; Shaheen, Ranad; Alkuraya, Fowzan S

2018-04-05

PurposeTo describe our experience with a large cohort (411 patients from 288 families) of various forms of skeletal dysplasia who were molecularly characterized.MethodsDetailed phenotyping and next-generation sequencing (panel and exome).ResultsOur analysis revealed 224 pathogenic/likely pathogenic variants (54 (24%) of which are novel) in 123 genes with established or tentative links to skeletal dysplasia. In addition, we propose 5 genes as candidate disease genes with suggestive biological links (WNT3A, SUCO, RIN1, DIP2C, and PAN2). Phenotypically, we note that our cohort spans 36 established phenotypic categories by the International Skeletal Dysplasia Nosology, as well as 18 novel skeletal dysplasia phenotypes that could not be classified under these categories, e.g., the novel C3orf17-related skeletal dysplasia. We also describe novel phenotypic aspects of well-known disease genes, e.g., PGAP3-related Toriello-Carey syndrome-like phenotype. We note a strong founder effect for many genes in our cohort, which allowed us to calculate a minimum disease burden for the autosomal recessive forms of skeletal dysplasia in our population (7.16E-04), which is much higher than the global average.ConclusionBy expanding the phenotypic, allelic, and locus heterogeneity of skeletal dysplasia in humans, we hope our study will improve the diagnostic rate of patients with these conditions.GENETICS in MEDICINE advance online publication, 5 April 2018; doi:10.1038/gim.2018.50.

A new conceptual model of coral biomineralisation: hypoxia as the physiological driver of skeletal extension

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S. Wooldridge

2013-05-01

Full Text Available That corals skeletons are built of aragonite crystals with taxonomy-linked ultrastructure has been well understood since the 19th century. Yet, the way by which corals control this crystallization process remains an unsolved question. Here, I outline a new conceptual model of coral biomineralisation that endeavours to relate known skeletal features with homeostatic functions beyond traditional growth (structural determinants. In particular, I propose that the dominant physiological driver of skeletal extension is night-time hypoxia, which is exacerbated by the respiratory oxygen demands of the coral's algal symbionts (= zooxanthellae. The model thus provides a new narrative to explain the high growth rate of symbiotic corals, by equating skeletal deposition with the "work-rate" of the coral host needed to maintain a stable and beneficial symbiosis. In this way, coral skeletons are interpreted as a continuous (long-run recording unit of the stability and functioning of the coral–algae endosymbiosis. After providing supportive evidence for the model across multiple scales of observation, I use coral core data from the Great Barrier Reef (Australia to highlight the disturbed nature of the symbiosis in recent decades, but suggest that its onset is consistent with a trajectory that has been followed since at least the start of the 1900s. In concluding, I outline how the proposed capacity of cnidarians (which includes modern reef corals to overcome the metabolic limitation of hypoxia via skeletogenesis also provides a new hypothesis to explain the sudden appearance in the fossil record of calcified skeletons at the Precambrian–Cambrian transition – and the ensuing rapid appearance of most major animal phyla.

Estimation of Correlation between Chronological Age, Skeletal Age and Dental Age in Children- A Cross-sectional Study.

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Macha, Madhulika; Lamba, Bharti; Avula, Jogendra Sai Sankar; Muthineni, Sridhar; Margana, Pratap Gowd Jai Shankar; Chitoori, Prasad

2017-09-01

In the modern era, identification and determination of age is imperative for diversity of reasons that include disputed birth records, premature delivery, legal issues and for validation of birth certificate for school admissions, adoption, marriage, job and immigration. Several growth assessment parameters like bone age, dental age and the combination of both have been applied for different population with variable outcomes. It has been well documented that the chronological age does not necessarily correlate with the maturational status of a child. Hence, efforts were made to determine a child's developmental age by using dental age (calcification of teeth) and skeletal age (skeletal maturation). The present study was aimed to correlate the chronological age, dental age and skeletal age in children from Southeastern region of Andhra Pradesh, India. Out of the total 900 screened children, only 100 subjects between age groups of 6-14 years with a mean age of 11.3±2.63 for males and 10.77±2.24 for females were selected for the study. Dental age was calculated by Demirjian method and skeletal age by modified Middle Phalanx of left hand third finger (MP3) method. Pearson's and Spearman's correlation tests were done to estimate the correlation between chronological, dental and skeletal ages among study population. There was a significant positive correlation between chronological age, dental age and all stages of MP3 among males. Similar results were observed in females, except for a non-significant moderate correlation between chronological age and dental age in the H stage of the MP3 region. The results of the present study revealed correlation with statistical significance (p<0.05) between chronological, dental and skeletal ages among all the subjects (48 males and 52 females) and females attained maturity earlier than males in the present study population.

A three-dimensional analysis of skeletal and dental characteristics in skeletal class III patients with facial asymmetry.

Science.gov (United States)

Yu, Jinfeng; Hu, Yun; Huang, Mingna; Chen, Jun; Ding, Xiaoqian; Zheng, Leilei

2018-03-15

To evaluate the skeletal and dental characteristics in skeletal class III patients with facial asymmetry and to analyse the relationships among various parts of the stomatognathic system to provide a theoretical basis for clinical practice. Asymmetric cone-beam computed tomography data acquired from 56 patients were evaluated using Mimics 10.0 and 3-Matic software. Skeletal and dental measurements were performed to assess the three-dimensional differences between two sides. Pearson correlation analysis was used to determine the correlations among measurements. Linear measurements, such as ramal height, mandible body length, ramal height above the sigmoid notch (RHASN), maxillary height, condylar height, buccal and total cancellous bone thickness, and measurements of condylar size, were significantly larger on the nondeviated side than on the deviated side (P orthodontic camouflage has limitations and potential risks. A combination of orthodontics and orthognathic surgery may be the advisable choice in patients with a menton deviation greater than 4 mm. An important association between vertical skeletal disharmony and dental compensation was also observed.

Is skeletal anchorage changing the limit of orthodontics?

DEFF Research Database (Denmark)

Melsen, Birte

2007-01-01

The limits for orthodontic treatment are often set by the lack of suitable anchorage. The mini-implant is used where conventional anchorage cannot be applied; not as a replacement for conventional anchorage. In patients with lack of teeth and reduced periodontium, skeletal anchorage allows...... and can be loaded immediately. The course will be addressed the following topics: Are the mini-implants replacing conventional anchorage? Why are orthodontic mini-implants necessary? The development of the skeletal anchorage systems The biological basis for the skeletal anchorage systems...... The characteristics of the different skeletal anchorage systems The insertion procedure The indications for the use of orthodontic mini-implants Treatment planning in relation to the use of mini-implants Case presentations...

Structural stability of hydrogenated amorphous carbon overcoats used in heat-assisted magnetic recording investigated by rapid thermal annealing

KAUST Repository

Wang, N.; Komvopoulos, K.; Rose, F.; Marchon, B.

2013-01-01

Ultrathin amorphous carbon (a-C) films are extensively used as protective overcoats of magnetic recording media. Increasing demands for even higher storage densities have necessitated the development of new storage technologies, such as heat-assisted magnetic recording (HAMR), which uses laser-assisted heating to record data on high-stability media that can store single bits in extremely small areas (∼1 Tbit/in.2). Because HAMR relies on locally changing the coercivity of the magnetic medium by raising the temperature above the Curie temperature for data to be stored by the magnetic write field, it raises a concern about the structural stability of the ultrathin a-C film. In this study, rapid thermal annealing (RTA) experiments were performed to examine the thermal stability of ultrathin hydrogenated amorphous carbon (a-C:H) films deposited by plasma-enhanced chemical vapor deposition. Structural changes in the a-C:H films caused by RTA were investigated by x-ray photoelectron spectroscopy, Raman spectroscopy, x-ray reflectivity, and conductive atomic force microscopy. The results show that the films exhibit thermal stability up to a maximum temperature in the range of 400-450 °C. Heating above this critical temperature leads to hydrogen depletion and sp 2 clustering. The critical temperature determined by the results of this study represents an upper bound of the temperature rise due to laser heating in HAMR hard-disk drives and the Curie temperature of magnetic materials used in HAMR hard disks. © 2013 American Institute of Physics.

Deep Carbon Observatory investigates Carbon from Crust to Core: An Academic Record of the History of Deep Carbon Science

Science.gov (United States)

Mitton, S. A.

2017-12-01

Carbon plays an unparalleled role in our lives: as the element of life, as the basis of most of society's energy, as the backbone of most new materials, and as the central focus in efforts to understand Earth's variable and uncertain climate. Yet in spite of carbon's importance, scientists remain largely ignorant of the physical, chemical, and biological behavior of many of Earth's carbon-bearing systems. The Deep Carbon Observatory (DCO) is a global research program to transform our understanding of carbon in Earth. At its heart, DCO is a community of scientists, from biologists to physicists, geoscientists to chemists, and many others whose work crosses these disciplinary lines, forging a new, integrative field of deep carbon science. As a historian of science, I specialise in the history of planetary science and astronomy since 1900. This is directed toward understanding of the history of the steps on the road to discovering the internal dynamics of our planet. Within a framework that describes the historical background to the new field of Earth System Science, I present the first history of deep carbon science. This project will identifies the key discoveries of deep carbon science. It will assess the impact of new knowledge on geochemistry, geodynamics, and geobiology. The project will lead to publication, in book form in 2019, of an illuminating narrative that will highlight the engaging human stories of many remarkable scientists and natural philosophers from whom we have learned about the complexity of Earth's internal world. On this journey of discovery we will encounter not just the pioneering researchers of deep carbon science, but also their institutions, their instrumental inventiveness, and their passion for exploration. The book is organised thematically around the four communities of the Deep Carbon Observatory: Deep Life, Extreme Physics and Chemistry, Reservoirs and Fluxes, and Deep Energy. The presentation has a gallery and list of Deep Carbon

Skeletal stem cells in space and time

DEFF Research Database (Denmark)

Kassem, Moustapha; Bianco, Paolo

2015-01-01

The nature, biological characteristics, and contribution to organ physiology of skeletal stem cells are not completely determined. Chan et al. and Worthley et al. demonstrate that a stem cell for skeletal tissues, and a system of more restricted, downstream progenitors, can be identified in mice...

Atmospheric carbon dioxide and the climate record

International Nuclear Information System (INIS)

Ellsaesser, H.W.

1989-04-01

This paper is an attempt to provide a summary review of conclusions from previous studies on this subject. Subject headings include: conceptualization of the greenhouse effect, the climatic effect of doubled CO 2 , interpretation of the climatic record, diagnosis of apparent and possible model deficiencies, and the palaeoclimatic record

Cardiac, Skeletal, and smooth muscle mitochondrial respiration

DEFF Research Database (Denmark)

Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I

2014-01-01

, skeletal, and smooth muscle was harvested from a total of 22 subjects (53±6 yrs) and mitochondrial respiration assessed in permeabilized fibers. Complex I+II, state 3 respiration, an index of oxidative phosphorylation capacity, fell progressively from cardiac, skeletal, to smooth muscle (54±1; 39±4; 15......±1 pmol•s(-1)•mg (-1), prespiration rates were normalized by CS (respiration...... per mitochondrial content), oxidative phosphorylation capacity was no longer different between the three muscle types. Interestingly, Complex I state 2 normalized for CS activity, an index of non-phosphorylating respiration per mitochondrial content, increased progressively from cardiac, skeletal...

Atmospheric carbon dioxide and the climate record

Energy Technology Data Exchange (ETDEWEB)

Ellsaesser, H.W.

1989-04-01

This paper is an attempt to provide a summary review of conclusions from previous studies on this subject. Subject headings include: conceptualization of the greenhouse effect, the climatic effect of doubled CO/sub 2/, interpretation of the climatic record, diagnosis of apparent and possible model deficiencies, and the palaeoclimatic record.

Biological and climate controls on North Atlantic marine carbon dynamics over the last millennium: Insights from an absolutely-dated shell based record from the North Icelandic Shelf

Science.gov (United States)

Hall, I. R.; Reynolds, D.; Scourse, J. D.; Richardson, C.; Wanamaker, A. D.; Butler, P. G.

2017-12-01

Given the rapid increase in atmospheric carbon dioxide concentrations (pCO2) over the industrial era there is a pressing need to construct longterm records of natural carbon cycling prior to this perturbation and to develop a more robust understanding of the role the oceans play in the sequestration of atmospheric carbon. Here we reconstruct the historical biological and climatic controls on the carbon isotopic (δ13C-shell) composition of the North Icelandic shelf waters over the last millennium derived from the shells of the long-lived marine bivalve mollusc Arctica islandica. Variability in the annually resolved δ13C-shell record is dominated by multi-decadal variability with a negative trend (-0.003±0.002‰yr-1) over the industrial era (1800-2000). This trend is consistent with the marine Suess effect brought about by the sequestration of isotopically light carbon (δ13C of CO2) derived from the burning of fossil fuels. Comparison of the δ13C-shell record with contemporary proxy archives, over the last millennium, and instrumental data over the 20th century, suggests that primary productivity and climate conditions over the sub-polar North Atlantic region played a vital role in driving inter-annual to multi-decadal scale variability in the δ13C-shell record. Our results highlight that relative shifts in the proportion of sub-polar mode waters and Arctic intermediate waters entrained onto the North Icelandic shelf, coupled with atmospheric circulation patterns associated with the winter North Atlantic Oscillation (wNAO), are the likely physical mechanisms that drive natural variations in seawater δ13C variability on the North Icelandic shelf.

The role of FFM accumulation and skeletal muscle architecture in powerlifting performance.

Science.gov (United States)

Brechue, William F; Abe, Takashi

2002-02-01

The purpose of this study was to determine the distribution and architectural characteristics of skeletal muscle in elite powerlifters, and to investigate their relationship to fat-free mat (FFM) accumulation and powerlifting performance. Twenty elite male powerlifters (including four world and three US national champions) volunteered for this study. FFM, skeletal muscle distribution (muscle thickness at 13 anatomical sites), and isolated muscle thickness and fascicle pennation angle (PAN) of the triceps long-head (TL), vastus lateralis, and gastrocnemius medialis (MG) muscles were measured with B-mode ultrasound. Fascicle length (FAL) was calculated. Best lifting performance in the bench press (BP), squat lift (SQT), and dead lift (DL) was recorded from competition performance. Significant correlations (P FFM and FFM relative to standing height (r = 0.86 to 0.95, P FFM (r = 0.59, P FFM and, therefore, may be limited by the ability to accumulate FFM. Additionally, muscle architecture appears to play an important role in powerlifting performance in that greater fascicle lengths are associated with greater FFM accumulation and powerlifting performance.

Primary sacrococcygeal chordoma with unusual skeletal muscle metastasis

Directory of Open Access Journals (Sweden)

Lisa Vu, MD

2014-01-01

Full Text Available Chordomas are rare neoplasms that do not often metastasize. Of the small percent that do metastasize, they very infrequently involve skeletal muscle. Only a few cases of skeletal muscle metastases have been reported in the literature. We report an unusual case of a patient with a primary sacrococcygeal chordoma who experienced a long period of remission but who subsequently developed recurrence and multiple metastatic lesions to skeletal muscles including the deltoid, triceps, and pectineus.

An analysis of correlation between occlusion classification and skeletal pattern

International Nuclear Information System (INIS)

Lu Xinhua; Cai Bin; Wang Dawei; Wu Liping

2003-01-01

Objective: To study the correlation between dental relationship and skeletal pattern of individuals. Methods: 194 cases were selected and classified by angle classification, incisor relationship and skeletal pattern respectively. The correlation of angle classification and incisor relationship to skeletal pattern was analyzed with SPSS 10.0. Results: The values of correlation index (Kappa) were 0.379 and 0.494 respectively. Conclusion: The incisor relationship is more consistent with skeletal pattern than angle classification

[Effects of lycopene on the skeletal system].

Science.gov (United States)

Sołtysiak, Patrycja; Folwarczna, Joanna

2015-02-21

Antioxidant substances of plant origin, such as lycopene, may favorably affect the skeletal system. Lycopene is a carotenoid pigment, responsible for characteristic red color of tomatoes. It is believed that lycopene may play a role in the prevention of various diseases; despite theoretical premises and results of experimental studies, the effectiveness of lycopene has not yet been clearly demonstrated in studies carried out in humans. The aim of the study was to present the current state of knowledge on the effects of lycopene on the osseous tissue in in vitro and in vivo experimental models and on the skeletal system in humans. Results of the studies indicate that lycopene may inhibit bone resorption. Favorable effects of high doses of lycopene on the rat skeletal system in experimental conditions, including the model of osteoporosis induced by estrogen deficiency, have been demonstrated. The few epidemiological and clinical studies, although not fully conclusive, suggest a possible beneficial effect of lycopene present in the diet on the skeletal system.

Dynamics of the Skeletal Muscle Secretome during Myoblast Differentiation

DEFF Research Database (Denmark)

Henningsen, Jeanette; Rigbolt, Kristoffer T G; Blagoev, Blagoy

2010-01-01

During recent years, increased efforts have focused on elucidating the secretory function of skeletal muscle. Through secreted molecules, skeletal muscle affects local muscle biology in an auto/paracrine manner as well as having systemic effects on other tissues. Here we used a quantitative...... proteomics platform to investigate the factors secreted during the differentiation of murine C2C12 skeletal muscle cells. Using triple encoding stable isotope labeling by amino acids in cell culture, we compared the secretomes at three different time points of muscle differentiation and followed the dynamics...... of the skeletal muscle as a prominent secretory organ. In addition to previously reported molecules, we identified many secreted proteins that have not previously been shown to be released from skeletal muscle cells nor shown to be differentially released during the process of myogenesis. We found 188...

Skeletal Muscle-specific G Protein-coupled Receptor Kinase 2 Ablation Alters Isolated Skeletal Muscle Mechanics and Enhances Clenbuterol-stimulated Hypertrophy.

Science.gov (United States)

Woodall, Benjamin P; Woodall, Meryl C; Luongo, Timothy S; Grisanti, Laurel A; Tilley, Douglas G; Elrod, John W; Koch, Walter J

2016-10-14

GRK2, a G protein-coupled receptor kinase, plays a critical role in cardiac physiology. Adrenergic receptors are the primary target for GRK2 activity in the heart; phosphorylation by GRK2 leads to desensitization of these receptors. As such, levels of GRK2 activity in the heart directly correlate with cardiac contractile function. Furthermore, increased expression of GRK2 after cardiac insult exacerbates injury and speeds progression to heart failure. Despite the importance of this kinase in both the physiology and pathophysiology of the heart, relatively little is known about the role of GRK2 in skeletal muscle function and disease. In this study we generated a novel skeletal muscle-specific GRK2 knock-out (KO) mouse (MLC-Cre:GRK2 fl/fl ) to gain a better understanding of the role of GRK2 in skeletal muscle physiology. In isolated muscle mechanics testing, GRK2 ablation caused a significant decrease in the specific force of contraction of the fast-twitch extensor digitorum longus muscle yet had no effect on the slow-twitch soleus muscle. Despite these effects in isolated muscle, exercise capacity was not altered in MLC-Cre:GRK2 fl/fl mice compared with wild-type controls. Skeletal muscle hypertrophy stimulated by clenbuterol, a β 2 -adrenergic receptor (β 2 AR) agonist, was significantly enhanced in MLC-Cre:GRK2 fl/fl mice; mechanistically, this seems to be due to increased clenbuterol-stimulated pro-hypertrophic Akt signaling in the GRK2 KO skeletal muscle. In summary, our study provides the first insights into the role of GRK2 in skeletal muscle physiology and points to a role for GRK2 as a modulator of contractile properties in skeletal muscle as well as β 2 AR-induced hypertrophy. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Skeletal Muscle-specific G Protein-coupled Receptor Kinase 2 Ablation Alters Isolated Skeletal Muscle Mechanics and Enhances Clenbuterol-stimulated Hypertrophy*

Science.gov (United States)

Woodall, Benjamin P.; Woodall, Meryl C.; Luongo, Timothy S.; Grisanti, Laurel A.; Tilley, Douglas G.; Elrod, John W.; Koch, Walter J.

2016-01-01

GRK2, a G protein-coupled receptor kinase, plays a critical role in cardiac physiology. Adrenergic receptors are the primary target for GRK2 activity in the heart; phosphorylation by GRK2 leads to desensitization of these receptors. As such, levels of GRK2 activity in the heart directly correlate with cardiac contractile function. Furthermore, increased expression of GRK2 after cardiac insult exacerbates injury and speeds progression to heart failure. Despite the importance of this kinase in both the physiology and pathophysiology of the heart, relatively little is known about the role of GRK2 in skeletal muscle function and disease. In this study we generated a novel skeletal muscle-specific GRK2 knock-out (KO) mouse (MLC-Cre:GRK2fl/fl) to gain a better understanding of the role of GRK2 in skeletal muscle physiology. In isolated muscle mechanics testing, GRK2 ablation caused a significant decrease in the specific force of contraction of the fast-twitch extensor digitorum longus muscle yet had no effect on the slow-twitch soleus muscle. Despite these effects in isolated muscle, exercise capacity was not altered in MLC-Cre:GRK2fl/fl mice compared with wild-type controls. Skeletal muscle hypertrophy stimulated by clenbuterol, a β2-adrenergic receptor (β2AR) agonist, was significantly enhanced in MLC-Cre:GRK2fl/fl mice; mechanistically, this seems to be due to increased clenbuterol-stimulated pro-hypertrophic Akt signaling in the GRK2 KO skeletal muscle. In summary, our study provides the first insights into the role of GRK2 in skeletal muscle physiology and points to a role for GRK2 as a modulator of contractile properties in skeletal muscle as well as β2AR-induced hypertrophy. PMID:27566547

Assessment of skeletal maturation with permanent mandibular second molar calcification stages among a group of Nepalese orthodontic patients

Directory of Open Access Journals (Sweden)

Giri J

2016-03-01

Full Text Available Jamal Giri,1 Basanta Kumar Shrestha,2 Rajiv Yadav,2 Tika Ram Ghimire21Department of Orthodontics, BP Koirala Institute of Health Sciences, Dharan, 2Department of Dentistry, Institute of Medicine, Kathmandu, Nepal Background: Assessment of growth status of a patient is a key component in orthodontic diagnosis and treatment planning for growing patients with skeletal discrepancy. Skeletal maturation based on hand-wrist radiograph and cervical vertebral maturation (CVM are commonly used methods of growth assessment. Studies have shown that stages of dental calcification can also be used to assess skeletal maturation status of an individual, whereas other studies have suggested that the relationship between dental calcification and skeletal maturation should be interpreted with caution owing to racial variation. Objective: To evaluate the relationship between permanent mandibular second molar calcification stages and skeletal maturity assessed by CVM among a group of Nepalese orthodontic patients. Materials and methods: One hundred and sixty-eight digital radiographs (84 orthopantomograms and 84 lateral cephalograms were obtained from the records of 84 patients who sought orthodontic treatment in Orthodontic and Dentofacial Orthopaedic Unit, Department of Dentistry, Institute of Medicine, Kathmandu. Two parameters were used in this study, namely, CVM stages from lateral cephalogram and Demirjian index (DI stages from orthopantomogram. The evaluation of digital radiographs was carried out on a computer screen with a resolution of 1,280×800 pixels. The association between DI stages of permanent mandibular second molar and CVM stages was assessed. Results: A statistically significant association was found between DI and CVM stages for both male and female subjects with Pearson's contingency coefficient value of 0.751 and 0.766 for male and female subjects, respectively. Conclusion: Skeletal maturation can be reliably assessed with dental calcification

Correlation of chronological, skeletal, and dental age in North Indian population

Directory of Open Access Journals (Sweden)

Madhurima Nanda

2017-01-01

Full Text Available Aim and Objectives: The aim of the study was to find out the correlation between chronological, dental, and skeletal age. Materials and Methods: Lateral cephalograms and orthopantomograms of 100 subjects of age ranging 9–14 years were obtained for the estimation of skeletal and dental age. Dental age was assessed using Demirjian's method; skeletal age was assessed using the new improved version of the cervical vertebral maturation method given by Baccetti, Franchi, and McNamara. Statistical analysis was carried out. Student's t-test and Spearman's coefficient correlation were used to assess the relation between chronological, skeletal, and dental age. Results: The Spearman's correlation coefficient was 0.777 (P < 0.001 between chronological and dental age, 0.516 (P < 0.001 between chronological and skeletal age, and 0.563 (P < 0.001 between dental and skeletal age. Conclusion: There is a good correlation between chronological and dental age in North Indian population which was higher for males as compared to females. A moderate correlation was found between chronological and skeletal age as well as between dental and skeletal age.

Molecular Signals and Skeletal Muscle Adaptation to Exercise

Directory of Open Access Journals (Sweden)

Mark Wilson

2013-09-01

Full Text Available The phenotypic plasticity of skeletal muscle affords a considerable degree of adaptability not seen in other bodily tissues. The mechanical properties of skeletal muscle are highly dependent on loading conditions. The extent of skeletal muscle plasticity is distinctly highlighted by a loss of muscle mass, or atrophy, after a period of reduced weight-bearing activity, for example during periods of extended bed rest, space flight and in spinal cord injury. On the other hand, increased mechanical loading, or resistance training, induces muscle growth, or hypertrophy. Endurance exercise performance is also dependent on the adaptability of skeletal muscle, especially muscles that contribute to posture, locomotion and the mechanics of breathing.  However, the molecular pathways governing skeletal muscle adaptations are yet to be satisfactorily delineated and require further investigation. Researchers in the areas of exercise physiology, physiotherapy and sports medicine are endeavoring to translate experimental knowledge into effective, innovative treatments and regimens in order to improve physical performance and health in both elite athletes and the general community. The efficacy of the translation of molecular biological paradigms in experimental exercise physiology has long been underappreciated. Indeed, molecular biology tools can now be used to answer questions regarding skeletal muscle adaptation in response to exercise and provide new frameworks to improve physical performance. Furthermore, transgenic animal models, knockout animal models and in vivo studies provide tools to test questions concerned with how exercise initiates adaptive changes in gene expression. In light of these perceived deficiencies, an attempt is made here to elucidate the molecular mechanisms of skeletal muscle adaptation to exercise. An examination will be made of the functional capacity of skeletal muscle to respond to a variety of exercise conditions, namely

Molecular Signals and Skeletal Muscle Adaptation to Exercise

Directory of Open Access Journals (Sweden)

Mark Wilson

2013-08-01

Full Text Available The phenotypic plasticity of skeletal muscle affords a considerable degree of adaptability not seen in other bodily tissues. The mechanical properties of skeletal muscle are highly dependent on loading conditions. The extent of skeletal muscle plasticity is distinctly highlighted by a loss of muscle mass, or atrophy, after a period of reduced weight-bearing activity, for example during periods of extended bed rest, space flight and in spinal cord injury. On the other hand, increased mechanical loading, or resistance training, induces muscle growth, or hypertrophy. Endurance exercise performance is also dependent on the adaptability of skeletal muscle, especially muscles that contribute to posture, locomotion and the mechanics of breathing. However, the molecular pathways governing skeletal muscle adaptations are yet to be satisfactorily delineated and require further investigation. Researchers in the areas of exercise physiology, physiotherapy and sports medicine are endeavoring to translate experimental knowledge into effective, innovative treatments and regimens in order to improve physical performance and health in both elite athletes and the general community. The efficacy of the translation of molecular biological paradigms in experimental exercise physiology has long been underappreciated. Indeed, molecular biology tools can now be used to answer questions regarding skeletal muscle adaptation in response to exercise and provide new frameworks to improve physical performance. Furthermore, transgenic animal models, knockout animal models and in vivo studies provide tools to test questions concerned with how exercise initiates adaptive changes in gene expression. In light of these perceived deficiencies, an attempt is made here to elucidate the molecular mechanisms of skeletal muscle adaptation to exercise. An examination will be made of the functional capacity of skeletal muscle to respond to a variety of exercise conditions, namely

Unusual Features of Extraarticular Skeletal Tuberculosis: New Classification and Differential Diagnosis

International Nuclear Information System (INIS)

Kim, Kun Sang; Park, Soo Soung

1983-01-01

Twenty two cases of extra articular skeletal tuberculosis which showed unusual radiological features are reported and classified into several categories with discussion on the differential diagnosis. Radiological patterns of skeletal tuberculosis is so variable that with any kind of skeletal changes the possibility of the skeletal tuberculosis should not be excluded between of lack of its classical patterns.

Purinergic receptors expressed in human skeletal muscle fibres

DEFF Research Database (Denmark)

Bornø, A; Ploug, Thorkil; Bune, L T

2012-01-01

distribution of purinergic receptors in skeletal muscle fibres. We speculate that the intracellular localization of purinergic receptors may reflect a role in regulation of muscle metabolism; further studies are nevertheless needed to determine the function of the purinergic system in skeletal muscle cells.......Purinergic receptors are present in most tissues and thought to be involved in various signalling pathways, including neural signalling, cell metabolism and local regulation of the microcirculation in skeletal muscles. The present study aims to determine the distribution and intracellular content...... of purinergic receptors in skeletal muscle fibres in patients with type 2 diabetes and age-matched controls. Muscle biopsies from vastus lateralis were obtained from six type 2 diabetic patients and seven age-matched controls. Purinergic receptors were analysed using light and confocal microscopy...

Health Occupations Module. The Skeletal System--I.

Science.gov (United States)

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on the skeletal system is one of eight modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module contains an introduction to the module topic, three objectives (e.g., define the skeletal system and list its functions), and three learning…

The essence of biophysical cues in skeletal muscle tissue engineering

NARCIS (Netherlands)

Langelaan, M.L.P.

2010-01-01

Skeletal muscle is an appealing topic for tissue engineering because of its variety in applications. Evidently, tissue engineered skeletal muscle can be used in the field of regenerative medicine to repair muscular defects or dystrophies. Engineered skeletal muscle constructs can also be used as a

Role of Akirin in Skeletal Myogenesis

Directory of Open Access Journals (Sweden)

Dingbiao Long

2013-02-01

Full Text Available Akirin is a recently discovered nuclear factor that plays an important role in innate immune responses. Beyond its role in innate immune responses, Akirin has recently been shown to play an important role in skeletal myogenesis. In this article, we will briefly review the structure and tissue distribution of Akirin and discuss recent advances in our understanding of its role and signal pathway in skeletal myogenesis.

Skeletal metastases from hepatoma: frequency, distribution, and radiographic features

International Nuclear Information System (INIS)

Kuhlman, J.E.; Fishman, E.K.; Leichner, P.K.; Magid, D.; Order, S.E.; Siegelman, S.S.

1986-01-01

Over the past 6 years, the authors evaluated 300 patients with hepatoma as part of phase 1 and 2 treatment protocol trials. Analysis of the available clinical data and radiographic studies revealed 22 patients (7.3%) with skeletal metastases demonstrated by radiography, computed tomography (CT), and/or nuclear scintigraphy. The plain film appearance of skeletal metastases from hepatoma was osteolytic in all cases. CT scanning best demonstrated the expansile, destructive nature of these metastases, which were often associated with large, bulky soft-tissue masses. Skeletal metastases from hepatomas demonstrated increased radiotracer uptake on standard bone scans and were gallium avid, similar to the hepatoma itself. In addition, they could be targeted therapeutically with I-131 antiferritin immunoglobulin. The most frequent sites of skeletal metastases were the ribs, spine, femur, pelvis, and humerus. An initial symptom in ten patients was skeletal pain corresponding to the osseous metastases. In five patients, pathologic fractures of the proximal femur or humerus developed and required total hip replacement or open-reduction internal fixation. Patients with long-standing cirrhosis or known hepatocellular carcinoma who also have skeletal symptoms should be evaluated for possible osseous metastases

Membranous lipodystrophy: skeletal findings on CT and MRI

Energy Technology Data Exchange (ETDEWEB)

Nwawka, O.K.; Schneider, Robert; Mintz, Douglas N. [Hospital for Special Surgery, Department of Radiology and Imaging, New York, NY (United States); Bansal, Manjula [Hospital for Special Surgery, Department of Pathology and Laboratory Medicine, New York, NY (United States); Lane, Joseph [Hospital for Special Surgery, Department of Orthopedic Surgery, New York, NY (United States)

2014-10-15

Membranous lipodystrophy, also known as Nasu-Hakola disease, is a rare hereditary condition with manifestations in the nervous and skeletal systems. The radiographic appearance of skeletal lesions has been well described in the literature. However, CT and MRI findings of lesions in the bone have not been documented to date. This report describes the radiographic, CT, MRI, and histopathologic skeletal findings in a case of membranous lipodystrophy. With corroborative pathologic findings, a diagnosis of membranous lipodystrophy on imaging allows for appropriate clinical management of disease manifestations. (orig.)

Skeletal traction and intramedullary nailing cost-effectiveness

African Journals Online (AJOL)

In the operative group 24 patients had union with one delayed union while in the traction group 12 patients had union, 9 with mal union and 4 delayed union. Conclusion: Intramedullary nailing is more cost-effective than skeletal traction. It met the dominant strategy, because it was significantly less costly than skeletal ...

Skeletal scintigraphic changes in osteoporosis treated with sodium fluoride: concise communication

International Nuclear Information System (INIS)

Schulz, E.E.; Libanati, C.R.; Farley, S.M.; Kirk, G.A.; Baylink, D.J.

1984-01-01

An appendicular skeletal response to sodium fluoride (NaF) was detected by total skeletal scintigrams. Twelve postmenopausal osteoporotic women were treated with NaF (88 mg/day) and calcium (1500 mg/day). Total skeletal scintigrams were obtained before and during treatment. Within 4 to 21 mo (mean: 8.3), all 12 patients showed new areas of increased uptake corresponding to metaphyseal regions and short bones of the appendicular skeleton. Nine patients showed an increase in serum alkaline phosphatase activity, which was attributed to an increase in the skeletal isoenzyme. Seven of 12 patients developed bone pain in one or more of the regions of increased uptake. This study establishes that the skeletal scintigram is a sensitive index of the peripheral skeletal response to NaF

mTOR as a Key Regulator in Maintaining Skeletal Muscle Mass

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Mee-Sup Yoon

2017-10-01

Full Text Available Maintenance of skeletal muscle mass is regulated by the balance between anabolic and catabolic processes. Mammalian target of rapamycin (mTOR is an evolutionarily conserved serine/threonine kinase, and is known to play vital roles in protein synthesis. Recent findings have continued to refine our understanding of the function of mTOR in maintaining skeletal muscle mass. mTOR controls the anabolic and catabolic signaling of skeletal muscle mass, resulting in the modulation of muscle hypertrophy and muscle wastage. This review will highlight the fundamental role of mTOR in skeletal muscle growth by summarizing the phenotype of skeletal-specific mTOR deficiency. In addition, the evidence that mTOR is a dual regulator of anabolism and catabolism in skeletal muscle mass will be discussed. A full understanding of mTOR signaling in the maintenance of skeletal muscle mass could help to develop mTOR-targeted therapeutics to prevent muscle wasting.

27 CFR 24.302 - Effervescent wine record.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Effervescent wine record..., DEPARTMENT OF THE TREASURY LIQUORS WINE Records and Reports § 24.302 Effervescent wine record. A proprietor who produces or receives sparkling wine or artificially carbonated wine in bond shall maintain records...

Skeletal maturity assessment using mandibular canine calcification stages

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Vildana Džemidžić

2016-11-01

Full Text Available Objective. The aims of this study were: to investigate the relationship between mandibular canine calcification stages and skeletal maturity; and to evaluate whether the mandibular canine calcification stages may be used as a reliable diagnostic tool for skeletal maturity assessment. Materials and methods. This study included 151 subjects: 81 females and 70 males, with ages ranging from 9 to 16 years (mean age: 12.29±1.86 years. The inclusion criteria for subjects were as follows: age between 9 and 16 years; good general health without any hormonal, nutritional, growth or dental development problems. Subjects who were undergoing or had previously received orthodontic treatment were not included in this study. The calcification stages of the left permanent mandibular canine were assessed according to the method of Demirjian, on panoramic radiographs. Assessment of skeletal maturity was carried out using the cervical vertebral maturation index (CVMI, as proposed by the Hassel-Farman method, on lateral cephalograms. The correlation between the calcification stages of mandibular canine and skeletal maturity was estimated separately for male and female subjects. Results. Correlation coefficients between calcification stages of mandibular canine and skeletal maturity were 0.895 for male and 0.701 for female subjects. Conclusions. A significant correlation was found between the calcification stages of the mandibular canine and skeletal maturity. The calcification stages of the mandibular canine show a satisfactory diagnostic performance only for assessment of pre-pubertal growth phase.

Extra-osseous uterine pathophysiology demonstrated on skeletal scintigraphy

International Nuclear Information System (INIS)

Mansberg, R.; Lewis, G.

1999-01-01

Full text: Skeletal scintigraphy is a sensitive procedure for evaluating disease and trauma involving the skeleton. Extra-skeletal pathophysiology is also often demonstrated. This may include uptake by tumours, soft tissue calcification and infection as well as renal pathology. Skeletal scintigraphy is often performed to evaluate hip and back pain and extra-osseous uterine pathophysiology can be demonstrated in both the early and late phases of the study as in the following cases. Three women underwent skeletal scintigraphy for the investigation of low back pain in two patients and post-partum hip pain in one. A large vascular uterus with deviation of the bladder was demonstrated in the post-partum patient. Increased pelvic vascularity and bladder deviation in the second patient was shown by ultrasound to correspond to a left-sided fibroid with associated adenomyosis. In the third case, right-sided pelvic vascularity and left bladder deviation were shown on ultrasound to be due to an anteverted, anteflexed uterus tilted to the right. These cases illustrate the importance of documenting extra-osseous findings on skeletal scintigraphy and the benefits of correlation with anatomical imaging

Skeletal and reticuloendothelial imaging in osteopetrosis: case report

International Nuclear Information System (INIS)

Park, H.M.; Lambertus, J.

1977-01-01

Skeletal and reticuloendothelial images, using Tc-99m HEDP and Tc-99m sulfur colloid, respectively, were obtained from two adult patients with osteopetrosis. Skeletal images demonstrated increased activity in multiple fracture sites, in mandibular osteomyelitis, in ends of splayed long bones adjacent to joints, and in the epiphyseal ends of short tubular bones. The remainder of the skeleton involved with osteopetrosis showed no generalized increased uptake of Tc-99m HEDP. These findings indicate that metabolic activity in this disease is abnormally increased in the usual areas of bone growth but appears normal elsewhere. Reticuloendothelial imaging showed an almost total lack of activity in the axial and peripheral skeletal marrow space. Anemia, however, was only moderate in these patients. Skeletal scintigraphy may be useful to evaluate the presence and extent of the frequent complications of osteopetrosis, namely fractures and osteomyelitis

PGC-1α-mediated adaptations in skeletal muscle

DEFF Research Database (Denmark)

Olesen, Jesper; Kiilerich, Kristian; Pilegaard, Henriette

2010-01-01

multiple pathways and functions underline the potential importance of PGC-1alpha in skeletal muscle adaptations in humans. The absence of exercise-induced PGC-1alpha-mediated gene regulation during a physical inactive lifestyle is suggested to lead to reduced oxidative capacity of skeletal muscle...... involved in angiogenesis and the anti-oxidant defence as well as to affect expression of inflammatory markers. Exercise increases PGC-1alpha transcription and potentially PGC-1alpha activity through post-translational modifications, and concomitant PGC-1alpha-mediated gene regulation is suggested...... to be an underlying mechanism for adaptations in skeletal muscle, when exercise is repeated. The current review presents some of the key findings in PGC-1alpha-mediated regulation of metabolically related, anti-oxidant and inflammatory proteins in skeletal muscle in the basal state and in response to exercise...

Single molecular image of cytosolic free Ca2+ of skeletal muscle cells in rats pre- and post-exercise-induced fatigue

Science.gov (United States)

Liu, Yi; Zhang, Heming; Zhao, Yanping; Liu, Zhiming

2009-08-01

A growing body of literature indicated the cytosolic free Ca2+ concentration of skeletal muscle cells changes significantly during exercise-induced fatigue. But it is confusing whether cytosolic free Ca2+ concentration increase or decrease. Furthermore, current researches mainly adopt muscle tissue homogenate as experiment material, but the studies based on cellular and subcellular level is seldom. This study is aimed to establish rat skeletal muscle cell model of exercise-induced fatigue, and confirm the change of cytosolic free Ca2+ concentration of skeletal muscle cells in rats preand post- exercise-induced fatigue. In this research, six male Wistar rats were randomly divided into two groups: control group (n=3) and exercise-induced fatigue group (n=3). The former group were allowed to freely move and the latter were forced to loaded swimming to exhaustive. Three days later, all the rats were sacrificed, the muscle tissue from the same site of skeletal muscle were taken out and digested to cells. After primary culture of the two kinds of skeletal muscle cells from tissue, a fluorescent dye-Fluo-3 AM was used to label the cytosolic free Ca2+. The fluorescent of Ca2+ was recorded by confocal laser scanning microscopy. The results indicated that, the Ca2+ fluorescence intensity of cells from the rat of exercise-induced fatigue group was significantly higher than those in control group. In conclusion, cytosolic free Ca2+ concentration of skeletal muscle cells has a close relation with exercise-induced fatigue, and the increase of cytosolic free Ca2+ concentration may be one of the important factors of exercise-induced fatigue.

Exercise Promotes Healthy Aging of Skeletal Muscle.

Science.gov (United States)

Cartee, Gregory D; Hepple, Russell T; Bamman, Marcas M; Zierath, Juleen R

2016-06-14

Primary aging is the progressive and inevitable process of bodily deterioration during adulthood. In skeletal muscle, primary aging causes defective mitochondrial energetics and reduced muscle mass. Secondary aging refers to additional deleterious structural and functional age-related changes caused by diseases and lifestyle factors. Secondary aging can exacerbate deficits in mitochondrial function and muscle mass, concomitant with the development of skeletal muscle insulin resistance. Exercise opposes deleterious effects of secondary aging by preventing the decline in mitochondrial respiration, mitigating aging-related loss of muscle mass and enhancing insulin sensitivity. This review focuses on mechanisms by which exercise promotes "healthy aging" by inducing modifications in skeletal muscle. Copyright © 2016 Elsevier Inc. All rights reserved.

Cryopreservation of human skeletal muscle impairs mitochondrial function

DEFF Research Database (Denmark)

Larsen, Steen; Wright-Paradis, C; Gnaiger, E

2012-01-01

functionality after long term cryopreservation (1 year). Skeletal muscle samples were preserved in dimethyl sulfoxide (DMSO) for later analysis. Human skeletal muscle fibres were thawed and permeabilised with saponin, and mitochondrial respiration was measured by high-resolution respirometry. The capacity...

Orthodontics-surgical combination therapy for Class III skeletal malocclusion

Directory of Open Access Journals (Sweden)

M S Ravi

2012-01-01

Full Text Available The correction of skeletal Class III malocclusion with severe mandibular prognathism in an adult individual requires surgical and Othodontic combination therapy. The inter disciplinary approach is the treatment of choice in most of the skeletal malocclusions. A case report of an adult individual with Class III malocclusion, having mandibular excess in sagittal and vertical plane and treated with orthodontics,, bilateral sagittal split osteotomy and Le - Forte I osteotomy for the correction of skeletal, dental and soft tissue discrepancies is herewith presented. The surgical-orthodontic combination therapy has resulted in near-normal skeletal, dental and soft tissue relationship, with marked improvement in the facial esthetics in turn, has helped the patient to improve the self-confidence level.

Erythropoietin receptor in human skeletal muscle and the effects of acute and long-term injections with recombinant human erythropoietin on the skeletal muscle

DEFF Research Database (Denmark)

Lundby, Carsten; Hellsten, Ylva; Jensen, Mie B. F.

2008-01-01

The presence and potential physiological role of the erythropoietin receptor (Epo-R) were examined in human skeletal muscle. In this study we demonstrate that Epo-R is present in the endothelium, smooth muscle cells, and in fractions of the sarcolemma of skeletal muscle fibers. To study...... the potential effects of Epo in human skeletal muscle, two separate studies were conducted: one to study the acute effects of a single Epo injection on skeletal muscle gene expression and plasma hormones and another to study the effects of long-term (14 wk) Epo treatment on skeletal muscle structure. Subjects...... was studied in subjects (n = 8) who received long-term Epo administration, and muscle biopsies were obtained before and after. Epo treatment did not alter mean fiber area (0.84 +/- 0.2 vs. 0.72 +/- 0.3 mm(2)), capillaries per fiber (4.3 +/- 0.5 vs. 4.4 +/- 1.3), or number of proliferating endothelial cells...

Overexpression of SMPX in adult skeletal muscle does not change skeletal muscle fiber type or size.

Directory of Open Access Journals (Sweden)

Einar Eftestøl

Full Text Available Mechanical factors such as stretch are thought to be important in the regulation of muscle phenotype. Small muscle protein X-linked (SMPX is upregulated by stretch in skeletal muscle and has been suggested to serve both as a transcription factor and a mechanosensor, possibly giving rise to changes in both fiber size and fiber type. We have used in vivo confocal imaging to study the subcellular localization of SMPX in skeletal muscle fibers of adult rats using a SMPX-EGFP fusion protein. The fusion protein was localized predominantly in repetitive double stripes flanking the Z-disc, and was excluded from all nuclei. This localization would be consistent with SMPX being a mechanoreceptor, but not with SMPX playing a role as a transcription factor. In vivo overexpression of ectopic SMPX in skeletal muscle of adult mice gave no significant changes in fiber type distribution or cross sectional area, thus a role of SMPX in regulating muscle phenotype remains unclear.

TAK1 regulates skeletal muscle mass and mitochondrial function

Science.gov (United States)

Hindi, Sajedah M.; Sato, Shuichi; Xiong, Guangyan; Bohnert, Kyle R.; Gibb, Andrew A.; Gallot, Yann S.; McMillan, Joseph D.; Hill, Bradford G.

2018-01-01

Skeletal muscle mass is regulated by a complex array of signaling pathways. TGF-β–activated kinase 1 (TAK1) is an important signaling protein, which regulates context-dependent activation of multiple intracellular pathways. However, the role of TAK1 in the regulation of skeletal muscle mass remains unknown. Here, we report that inducible inactivation of TAK1 causes severe muscle wasting, leading to kyphosis, in both young and adult mice.. Inactivation of TAK1 inhibits protein synthesis and induces proteolysis, potentially through upregulating the activity of the ubiquitin-proteasome system and autophagy. Phosphorylation and enzymatic activity of AMPK are increased, whereas levels of phosphorylated mTOR and p38 MAPK are diminished upon inducible inactivation of TAK1 in skeletal muscle. In addition, targeted inactivation of TAK1 leads to the accumulation of dysfunctional mitochondria and oxidative stress in skeletal muscle of adult mice. Inhibition of TAK1 does not attenuate denervation-induced muscle wasting in adult mice. Finally, TAK1 activity is highly upregulated during overload-induced skeletal muscle growth, and inactivation of TAK1 prevents myofiber hypertrophy in response to functional overload. Overall, our study demonstrates that TAK1 is a key regulator of skeletal muscle mass and oxidative metabolism. PMID:29415881

Application of skeletal age based on x-ray in selecting sports talents

Science.gov (United States)

Mao, Zongzhen; Xu, Guodong; Song, Tao

2012-01-01

Skeletal age has been studied and proved that for most elite athletes, it was coincident with the chronological ages when they were young. In order to explore the application of skeletal age in selecting sports talent, 32 athletes (female, chronological age 5-12 y) were chosen from the Gymnastics Training Base in this study. Their left hand-wrists were photographed with X-rays, and then the skeletal ages were estimated by Chinese version of the Tanner-Whitehouse Skeletal Maturity Assessment System. At the same time, their body shapes, functions, and sports ability were also measured. Results showed that 71.88% of the skeletal age was proportional to their chronological age (+/- 1 y); while 18.75% of the skeletal maturity was retarded by 1- 2 year, 9.37% of those was advanced more than 1 year. On the other hand, the body shape, functions and sports ability of the athletes were positively related with their skeletal maturity. This study proved that the determination of skeletal maturity is a reliable evaluation for selecting sports talent. A further study on the influence of gymnastics on the skeletal age is of great significance.

Coral skeletal δ15N reveals isotopic traces of an agricultural revolution

International Nuclear Information System (INIS)

Marion, Guy S.; Dunbar, Robert B.; Mucciarone, David A.; Kremer, James N.; Lansing, J. Stephen; Arthawiguna, Alit

2005-01-01

This study introduces a new method of tracing the history of nutrient loading in coastal oceans via δ 15 N analysis of organic nitrogen preserved in the skeleton of the massive Porites coral. Four coral cores were collected in Bali, Indonesia, from reefs exposed to high levels of fertilizers in agricultural run-off, from lagoonal corals impacted by sewage, and from a reef located 30 km offshore. Skeletal δ 15 N in the agriculturally exposed coral declined from 10.7 ± 0.4 per mille in 1970-1971, when synthetic fertilizers (-0.8 per mille ± 0.2 per mille ) were introduced to Bali, to a depleted 'anthropogenic' baseline of 3.5 per mille ± 0.4% in the mid-1990s. δ 15 N values were negatively correlated with rainfall, suggesting that marine δ 15 N lowers during flood-born influxes of waste fertilizers. Reef cores exposed to untreated sewage in terrestrial discharge were enriched (7.8 and 7.3 ± 0.4 per mille ), while the offshore core reflected background oceanic signals (6.2 ± 0.4 per mille). δ 15 N, N concentration, and C:N systematics indicate that the N isotopic composition of skeletal organic matter was generally well preserved over 30 years. We suggest that skeletal organic δ 15 N can serve as a recorder of past nitrogen sources. In Bali, this tracer suggests that the intensification of Western style agricultural practices since 1970 are contributing to the degradation of coastal coral reefs

Meniscus transplantation in skeletally immature patients.

Science.gov (United States)

Kocher, Mininder S; Tepolt, Frances A; Vavken, Patrick

2016-07-01

Meniscal pathology in skeletally immature patients includes meniscal tears and discoid lateral meniscus. Total or subtotal meniscectomy may occur in patients with discoid lateral meniscus or severe meniscal tears. Meniscal transplantation may be an option in skeletally immature patients status after total or subtotal meniscectomy with knee symptoms or dysfunction. This study focuses on the surgical technique and short-term outcomes of meniscus transplantation in skeletally immature patients. We reviewed our clinical database for skeletally immature patients who had undergone meniscus transplantation with a minimum of 2 years of follow-up. Patients were contacted, invited for a physical exam, and asked to complete a Pedi-IKDC, Lysholm, and Tegner outcomes questionnaire. The study protocol was approved by the responsible institutional review board. Three patients (two females/one male) were eligible for the study, each of whom responded to our invitation indicating availability for physical exam and questionnaire. Two patients had undergone subtotal discoid meniscus resection, leading to early lateral compartment degeneration. One patient developed advanced degeneration after a delay in treatment for a medial bucket-handle tear associated with anterior cruciate ligament rupture. The mean age of the patients at the time of surgery was 12.6±2.3 years. At a mean follow-up of 31±20 months, the mean Pedi-IKDC score was 68.3±4, the mean Lysholm was 55.7±22.3, and the median Tegner was 7 points. There were no indications of growth deformity during the regular postoperative radiological assessments. One patient required subsequent lysis of adhesions along the lateral mini arthrotomy and mobilization under anesthesia. The other two patients were able to return to sports at the same level as before meniscus transplantation and were able to do so within 9 months postoperatively. Over-resection of discoid menisci as well as untreated meniscus injury, the latter typically in

Skeletal age assessment in children using an open compact MRI system.

Science.gov (United States)

Terada, Yasuhiko; Kono, Saki; Tamada, Daiki; Uchiumi, Tomomi; Kose, Katsumi; Miyagi, Ryo; Yamabe, Eiko; Yoshioka, Hiroshi

2013-06-01

MRI may be a noninvasive and alternative tool for skeletal age assessment in children, although few studies have reported on this topic. In this article, skeletal age was assessed over a wide range of ages using an open, compact MRI optimized for the imaging of a child's hand and wrist, and its validity was evaluated. MR images and their three-dimensional segmentation visualized detailed skeletal features of each bone in the hand and wrist. Skeletal age was then independently scored from the MR images by two raters, according to the Tanner-Whitehouse Japan system. The skeletal age assessed by MR rating demonstrated a strong positive correlation with chronological age. The intrarater and inter-rater reproducibilities were significantly high. These results demonstrate the validity and reliability of skeletal age assessment using MRI. Copyright © 2012 Wiley Periodicals, Inc.

Developmental expression of the alpha-skeletal actin gene

Directory of Open Access Journals (Sweden)

Vonk Freek J

2008-06-01

Full Text Available Abstract Background Actin is a cytoskeletal protein which exerts a broad range of functions in almost all eukaryotic cells. In higher vertebrates, six primary actin isoforms can be distinguished: alpha-skeletal, alpha-cardiac, alpha-smooth muscle, gamma-smooth muscle, beta-cytoplasmic and gamma-cytoplasmic isoactin. Expression of these actin isoforms during vertebrate development is highly regulated in a temporal and tissue-specific manner, but the mechanisms and the specific differences are currently not well understood. All members of the actin multigene family are highly conserved, suggesting that there is a high selective pressure on these proteins. Results We present here a model for the evolution of the genomic organization of alpha-skeletal actin and by molecular modeling, illustrate the structural differences of actin proteins of different phyla. We further describe and compare alpha-skeletal actin expression in two developmental stages of five vertebrate species (mouse, chicken, snake, salamander and fish. Our findings confirm that alpha-skeletal actin is expressed in skeletal muscle and in the heart of all five species. In addition, we identify many novel non-muscular expression domains including several in the central nervous system. Conclusion Our results show that the high sequence homology of alpha-skeletal actins is reflected by similarities of their 3 dimensional protein structures, as well as by conserved gene expression patterns during vertebrate development. Nonetheless, we find here important differences in 3D structures, in gene architectures and identify novel expression domains for this structural and functional important gene.

Skeletal class III camouflage by mandibular incisor extraction: A case report

OpenAIRE

Janardhanan Kumaresan; Tamizharasi Senthil Kumar; Senthil Kumar

2014-01-01

Treatment planning in orthodontics plays a key role in determining the successful treatment of any kind of malocclusion. Skeletal class III malocclusions are generally difficult to treat because of the complex nature of the skeletal and dental manifestations they produce. Mild to moderate skeletal class III malocclusions sometimes have an acceptable facial profile where orthodontic camouflage is possible. In this case report, camouflage of a mild skeletal class III is done by the extraction o...

Intraurethral Injection of Autologous Minced Skeletal Muscle

DEFF Research Database (Denmark)

Gräs, Søren; Klarskov, Niels; Lose, Gunnar

2014-01-01

noted. CONCLUSIONS: Intraurethral injection of minced autologous muscle tissue is a simple surgical procedure that appears safe and moderately effective in women with uncomplicated stress urinary incontinence. It compares well to a more complicated regenerative strategy using in vitro expanded muscle......PURPOSE: Intraurethral injection of in vitro expanded autologous skeletal muscle derived cells is a new regenerative therapy for stress urinary incontinence. We examined the efficacy and safety of a simpler alternative strategy using freshly harvested, minced autologous skeletal muscle tissue...... with its inherent content of regenerative cells. MATERIALS AND METHODS: A total of 20 and 15 women with uncomplicated and complicated stress urinary incontinence, respectively, received intraurethral injections of minced autologous skeletal muscle tissue and were followed for 1 year. Efficacy was assessed...

Increased skeletal muscle capillarization enhances insulin sensitivity

DEFF Research Database (Denmark)

Åkerström, Thorbjörn; Laub, Lasse; Vedel, Kenneth

2014-01-01

Increased skeletal muscle capillarization is associated with improved glucose tolerance and insulin sensitivity. However, a possible causal relationship has not previously been identified. We therefore investigated whether increased skeletal muscle capillarization increases insulin sensitivity....... Skeletal muscle specific angiogenesis was induced by adding the α1-adrenergic receptor antagonist Prazosin to the drinking water of Sprague Dawley rats (n=33) while 34 rats served as controls. Insulin sensitivity was measured ≥40 h after termination of the 3-week Prazosin treatment, which ensured...... that Prazosin was cleared from the blood stream. Whole-body insulin sensitivity was measured in conscious, unrestrained rats by hyperinsulinemic euglycemic clamp. Tissue specific insulin sensitivity was assessed by administration of 2-deoxy-[(3)H]-Glucose during the plateau phase of the clamp. Whole...

Development and external validation of nomograms to predict the risk of skeletal metastasis at the time of diagnosis and skeletal metastasis-free survival in nasopharyngeal carcinoma.

Science.gov (United States)

Yang, Lin; Xia, Liangping; Wang, Yan; He, Shasha; Chen, Haiyang; Liang, Shaobo; Peng, Peijian; Hong, Shaodong; Chen, Yong

2017-09-06

The skeletal system is the most common site of distant metastasis in nasopharyngeal carcinoma (NPC); various prognostic factors have been reported for skeletal metastasis, though most studies have focused on a single factor. We aimed to establish nomograms to effectively predict skeletal metastasis at initial diagnosis (SMAD) and skeletal metastasis-free survival (SMFS) in NPC. A total of 2685 patients with NPC who received bone scintigraphy (BS) and/or 18F-deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and 2496 patients without skeletal metastasis were retrospectively assessed to develop individual nomograms for SMAD and SMFS. The models were validated externally using separate cohorts of 1329 and 1231 patients treated at two other institutions. Five independent prognostic factors were included in each nomogram. The SMAD nomogram had a significantly higher c-index than the TNM staging system (training cohort, P = 0.005; validation cohort, P system (P skeletal metastasis, which may improve counseling and facilitate individualized management of patients with NPC.

US of the hips in skeletal dysplasias and chromosomal aberrations

International Nuclear Information System (INIS)

Langer, R.; Langer, M.F.J.; Zwicker, C.

1987-01-01

Since January 1984 all newborns and infants with skeletal dysplasias and chromosomal aberrations were investigated by hip US, in addition to plain x-ray surveys. The authors observed one chondroectodermal dysplasia, one congenital spondyloepiphysial dysplasia, one cleidocranial dysplasia, one fibrochondrogenesis, two diastrophic dysplasias, and eight trisomies. The abnormalities of the hip joints could be demonstrated, and were compared with the findings on plain films. Especially skeletal dysplasias with abundant presence of cartilage were well visible. The newborn with trisomies showed normal hip joints. In the authors' opinion, all newborns with skeletal dysplasias should be investigated by hip sonography, in addition to skeletal radiography

The skeletal system

NARCIS (Netherlands)

Nikkels, PGJ

2015-01-01

Skeletal dysplasias are a group of disorders with a disturbance in development and/or growth of cartilage and/or bone. Epiphysis, metaphysis, and diaphysis of long bones are affected in a generalized manner with or without involvement of membranous bone of the skull. A dysostosis affects one or some

Skeletal injuries in small mammals: a multispecies assessment of prevalence and location

Science.gov (United States)

Stephens, Ryan B.; Burke, Christopher B.; Woodman, Neal; Poland, Lily B.; Rowe, Rebecca J.

2018-01-01

Wild mammals are known to survive injuries that result in skeletal abnormalities. Quantifying and comparing skeletal injuries among species can provide insight into the factors that cause skeletal injuries and enable survival following an injury. We documented the prevalence and location of structural bone abnormalities in a community of 7 small mammal species inhabiting the White Mountains of New Hampshire. These species differ in locomotion type and levels of intraspecific aggression. Overall, the majority of injuries were to the ribs or caudal vertebrae. Incidence of skeletal injuries was highest in older animals, indicating that injuries accumulate over a lifetime. Compared to species with ambulatory locomotion, those with more specialized (semi-fossorial, saltatorial, and scansorial) locomotion exhibited fewer skeletal abnormalities in the arms and legs, which we hypothesize is a result of a lesser ability to survive limb injuries. Patterns of skeletal injuries in shrews (Soricidae) were consistent with intraspecific aggression, particularly in males, whereas skeletal injuries in rodents (Rodentia) were more likely accidental or resulting from interactions with predators. Our results demonstrate that both the incidence and pattern of skeletal injuries vary by species and suggest that the ability of an individual to survive a specific skeletal injury depends on its severity and location as well as the locomotor mode of the species involved.

State of Skeletal Muscle Tissue in Women in the Ukrainian Population

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V.V. Povoroznyuk

2015-10-01

Full Text Available Today among geriatric syndromes, world scientists pay much attention to the study of sarcopenia. It was found that the evaluation of skeletal muscle strength has a significant correlation with the risk of falls, disability, deterioration in the quality of life, duration of hospitalization. It is proved that measurements of skeletal muscle strength, but not the determination of skeletal muscles mass, are strong and independent predictors of mortality in the elderly. Further researches are needed to study the characteristics of weight loss, strength and function of skeletal muscle with age in individuals of different sex and age. The objective of this study was to explore the features of strength and functionality of skeletal muscle tissue in women of all ages. The study involved 248 women, who were divided into groups by decades depending on age: 20–29, 30–39, 40–49, 50–59, 60–69, 70–79, 80–89 years. Skeletal muscle strength was evaluated using spring carpal dynamometer. Functions of skeletal muscles and the risk of falls were assessed using special tests. Fat-free mass of the whole body, upper and lower extremities was evaluated by means of dual-energy X-ray absorptiometry (Prodigy, GEHC Lunar, Madison, WI, USA. The study found that maximal values of strength and functional capacity of skeletal muscles were observed in women in the age group of 20–29 years. The significant loss of skeletal muscle strength is being detected in individuals from the age group of 60–69 years and older. When determining the functional capacity of skeletal muscles and risk of falls, significantly worse performance was established in women older than 50 years compared to those in women in the age group of 20–29 years.

The diagnosis of skeletal dysplasias: a multidisciplinary approach

International Nuclear Information System (INIS)

Mortier, Geert R.

2001-01-01

Skeletal dysplasias are heritable connective tissue disorders affecting skeletal morphogenesis and development. They represent a heterogeneous group of genetic disorders with more than 200 different entities being delineated to date. Because of this diversity, the diagnosis of a skeletal dysplasia is usually based on a combination of clinical, radiographic, morphologic, and, in some instances, biochemical and molecular studies. Tremendous advances have been made in the elucidation of the genetic defect of several of these conditions over the past 10 years. This progress has provided us with more insights into the genes controlling normal skeletal development. It also has opened new diagnostic perspectives. For several disorders, identification of the causal gene allows us now to confirm with a molecular test the diagnosis postulated on the basis of clinical, radiographic and/or morphologic studies. It also enables us to establish the diagnosis early in pregnancy. An accurate diagnosis is not only important for proper management of the affected individual but also the cornerstone for adequate genetic counseling

Skeletal blood flow: implications for bone-scan interpretation

International Nuclear Information System (INIS)

Charkes, N.D.

1980-01-01

The dispersion of the skeleton throughout the body and its complex vascular anatomy require indirect methods for the measurement of skeletal blood flow. The results of one such method, compartmental analysis of skeletal tracer kinetics, are presented. The assumptions underlying the models were tested in animals and found to be in agreement with experimental observations. Based upon the models and the experimental results, inferences concerning bone-scan interpretation can be drawn: decreased cardiac output produces low-contrast (technically poor) scans; decreased skeletal flow produces photon-deficient lesions; increase of cardiac output or of generalized systemic blood flow is undetectable 1 to 2 h after dose; increased local skeletal blood flow results from disturbance of the bone microvasculature and can occur from neurologic (sympatholytic) disorders or in association with focal abnormalities that also incite the formation of reactive bone (e.g., metastasis, fracture, etc.). Mathematical solutions of tracer kinetic data thus become relevant to bone-scan interpretation

The diagnosis of skeletal dysplasias: a multidisciplinary approach

Energy Technology Data Exchange (ETDEWEB)

Mortier, Geert R. E-mail: geert.mortier@rug.ac.be

2001-12-01

Skeletal dysplasias are heritable connective tissue disorders affecting skeletal morphogenesis and development. They represent a heterogeneous group of genetic disorders with more than 200 different entities being delineated to date. Because of this diversity, the diagnosis of a skeletal dysplasia is usually based on a combination of clinical, radiographic, morphologic, and, in some instances, biochemical and molecular studies. Tremendous advances have been made in the elucidation of the genetic defect of several of these conditions over the past 10 years. This progress has provided us with more insights into the genes controlling normal skeletal development. It also has opened new diagnostic perspectives. For several disorders, identification of the causal gene allows us now to confirm with a molecular test the diagnosis postulated on the basis of clinical, radiographic and/or morphologic studies. It also enables us to establish the diagnosis early in pregnancy. An accurate diagnosis is not only important for proper management of the affected individual but also the cornerstone for adequate genetic counseling.

Stability of skeletal changes induced by growth modulation procedures in the treatment of skeletal Class II malocclusion

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Prashantha Govinakovi Shivamurthy

2016-01-01

Full Text Available Objective: Objective of this study, based on an evaluation of lateral cephalograms, was to evaluate the degree of skeletal changes produced by the various growth modulative procedures in the treatment of skeletal Class II malocclusion and to characterize the stability of these changes in the years after treatment. Materials and Methods: Total of 40 patients with Class II malocclusion was divided into three groups according to appliance used, i.e. removable or fixed functional appliances (n = 10, combination of functional appliance with headgear (n = 10, and only headgear (n = 10. In addition, almost a matched control group (n = 10 also characterized by skeletal Class II pattern and were under observation, for more than 2 years was also selected. Lateral cephalograms of each patient were taken at the start of treatment (T1, at its completion (T2, and long-term posttreatment (T3. Results: This study showed significant improvement in maxillomandibular relationship in treated group compared to control group, and the changes remained stable in posttreatment phase. Restriction of maxillary growth was evident in headgear and combination groups whereas significant forward movement of the mandible was seen in functional group. Conclusion: Analysis of lateral cephalograms indicates that growth modulation therapy in angle Class II malocclusion brings about desired skeletal changes which remain relatively stable over a long-term period.

A Cenozoic record of the equatorial Pacific carbonate compensation depth

NARCIS (Netherlands)

Pälike, H.; Lyle, M.W.; Nishi, H.; Raffi, I.; Ridgwell, A.; Gamage, K.; Klaus, A.; Acton, G.; Anderson, L.; Backman, J.; Baldauf, J.; Beltran, C.; Bohaty, S.M.; Bown, P.; Busch, W.; Channell, J.E.T.; Chun, C.O.J.; Delaney, M.; Dewangan, P.; Jones, T.D.; Edgar, K.M.; Evans, H.; Fitch, P.; Foster, G.L.; Gussone, N.; Hasegawa, H.; Hathorne, E.C.; Hayashi, H.; Herrle, J.O.; Holbourn, A.; Hovan, S.; Hyeong, K.; Iijima, K.; Ito, T.; Kamikuri, S.; Kimoto, K.; Kuroda, J.; Leon-Rodriguez, L.; Malinverno, A.; Moore, T.C.; Murphy, B.H.; Murphy, D.P.; Nakamura, H.; Organe, K.; Ohneiser, C.; Richter, C.; Robinson, R.; Rohling, E.J.; Romero, O.; Sawada, K.; Scher, H.; Schneider, L.; Sluijs, A.; Takata, H.; Tian, J.; Tsujimoto, A.; Wade, B.S.; Westerhold, T.; Wilkens, R.; Williams, T.; Wilson, P.A.; Yamamoto, Y.; Yamamoto, S.; Yamazaki, T.; Zeebe, R.E.

2012-01-01

Atmospheric carbon dioxide concentrations and climate are regulated on geological timescales by the balance between carboninput fromvolcanicandmetamorphicoutgassingandits removalbyweathering feedbacks; these feedbacks involve the erosion of silicate rocks and organic-carbon-bearing rocks. The

Genetic engineering for skeletal regenerative medicine.

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Gersbach, Charles A; Phillips, Jennifer E; García, Andrés J

2007-01-01

The clinical challenges of skeletal regenerative medicine have motivated significant advances in cellular and tissue engineering in recent years. In particular, advances in molecular biology have provided the tools necessary for the design of gene-based strategies for skeletal tissue repair. Consequently, genetic engineering has emerged as a promising method to address the need for sustained and robust cellular differentiation and extracellular matrix production. As a result, gene therapy has been established as a conventional approach to enhance cellular activities for skeletal tissue repair. Recent literature clearly demonstrates that genetic engineering is a principal factor in constructing effective methods for tissue engineering approaches to bone, cartilage, and connective tissue regeneration. This review highlights this literature, including advances in the development of efficacious gene carriers, novel cell sources, successful delivery strategies, and optimal target genes. The current status of the field and the challenges impeding the clinical realization of these approaches are also discussed.

Role of skeletal muscle in lung development.

Science.gov (United States)

Baguma-Nibasheka, Mark; Gugic, Dijana; Saraga-Babic, Mirna; Kablar, Boris

2012-07-01

Skeletal (striated) muscle is one of the four basic tissue types, together with the epithelium, connective and nervous tissues. Lungs, on the other hand, develop from the foregut and among various cell types contain smooth, but not skeletal muscle. Therefore, during earlier stages of development, it is unlikely that skeletal muscle and lung depend on each other. However, during the later stages of development, respiratory muscle, primarily the diaphragm and the intercostal muscles, execute so called fetal breathing-like movements (FBMs), that are essential for lung growth and cell differentiation. In fact, the absence of FBMs results in pulmonary hypoplasia, the most common cause of death in the first week of human neonatal life. Most knowledge on this topic arises from in vivo experiments on larger animals and from various in vitro experiments. In the current era of mouse mutagenesis and functional genomics, it was our goal to develop a mouse model for pulmonary hypoplasia. We employed various genetically engineered mice lacking different groups of respiratory muscles or lacking all the skeletal muscle and established the criteria for pulmonary hypoplasia in mice, and therefore established a mouse model for this disease. We followed up this discovery with systematic subtractive microarray analysis approach and revealed novel functions in lung development and disease for several molecules. We believe that our approach combines elements of both in vivo and in vitro approaches and allows us to study the function of a series of molecules in the context of lung development and disease and, simultaneously, in the context of lung's dependence on skeletal muscle-executed FBMs.

Real time ray tracing of skeletal implicit surfaces

DEFF Research Database (Denmark)

Rouiller, Olivier; Bærentzen, Jakob Andreas

Modeling and rendering in real time is usually done via rasterization of polygonal meshes. We present a method to model with skeletal implicit surfaces and an algorithm to ray trace these surfaces in real time in the GPU. Our skeletal representation of the surfaces allows to create smooth models...

A descriptive study of accidental skeletal injuries and non-accidental skeletal injuries of child maltreatment.

Science.gov (United States)

Ghanem, Maha A H; Moustafa, Tarek A; Megahed, Haidy M; Salama, Naglaa; Ghitani, Sara A

2018-02-01

Lack of awareness and recognition of child maltreatment is the major reason behind underreporting. All victims often interact with the health care system for routine or emergency care. In several research works, non-accidental fractures are the second most common injury in maltreated children and it is represented up to one-third of cases. To determine the incidence of different types of accidental and non-accidental skeletal injuries among children, estimate the severity of injuries according to the modified injury severity score and to determine the degree of fractures either closed or opened (Gustiloe-Anderson open fracture classification). Moreover, identifying fractures resulting from child abuse and neglect. This aimed for early recognition of non-accidental nature of fractures in child maltreatment that can prevent further morbidity and mortality. A descriptive study was carried out on all children (109) with skeletal injuries who were admitted to both Main Alexandria and El-Hadara Orthopedic and Traumatology University Hospitals during six months. History, physical examination and investigations were done for the patients. A detailed questionnaire was taken to diagnose child abuse and neglect. Gustiloe-Anderson open fracture classification was used to estimate the degree of open fractures. Out of 109 children, twelve cases (11%) were categorized as child maltreatment. One case was physical abuse, eight cases (7.3%) were child neglect and three cases (2.8%) were labour exploitation. Road traffic accidents (RTA) was the commonest cause of skeletal injuries followed by falling from height. Regarding falls, they included 4 cases of stair falls in neglected children and another four cases of falling from height (balcony/window). The remaining 36 cases of falls were accidental. The skeletal injuries were in the form of fractures in 99 cases, dislocation in two cases, both fracture and/or dislocation in three cases, and bone deformity from brachial plexus injury

Regulatory mechanisms of skeletal muscle protein turnover during exercise

DEFF Research Database (Denmark)

Rose, Adam John; Richter, Erik

2009-01-01

Skeletal muscle protein turnover is a relatively slow metabolic process that is altered by various physiological stimuli such as feeding/fasting and exercise. During exercise, catabolism of amino acids contributes very little to ATP turnover in working muscle. With regards to protein turnover......, there is now consistent data from tracer studies in rodents and humans showing that global protein synthesis is blunted in working skeletal muscle. Whether there is altered skeletal muscle protein breakdown during exercise remains unclear. The blunting of protein synthesis is believed to be mediated...... downstream of changes in intracellular Ca(2+) and energy turnover. In particular, a signaling cascade involving Ca(2+)-calmodulin-eEF2 kinase-eEF2 is implicated. The possible functional significance of altered protein turnover in working skeletal muscle during exercise is discussed. Further work...

Carbon 13 and oxygen 18 isotope record of the early eocene nammal formation, salt range, pakistan

International Nuclear Information System (INIS)

Ghazi, S.; Sajid, Z.

2014-01-01

The Nammal Formation is the lowermost unit of the Early Eocene succession in the Salt Range, Pakistan. It is well exposed throughout the Salt Range. The Nammal Formation having 30 to 35 meters thickness is predominantly composed of nodular limestone interbedded with marl and shale. The present study was focussed on stable carbon 13 and oxygen 18 isotopic analysis based on data from two stratigraphically important sections. The samples from the Nilawahan section provided with the delta 13C values varied between 1.34 to -1.56 (VPDB) and values of delta 18O fluctuated between -4.47 to -6.59 (VPDB). Likewise the sample analysis of BadshahPur section exhibited that the delta 13C values changes from 1.09 to -1.65 (VPDB) and delta 18O values range from -4.17 to -6.85 (VPDB). The isotopic records of carbon 13 and oxygen 18 indicated the shallow marine deposition of the Nammal Formation under tropical conditions. It highlighted the palaeo climatic and diagenetic conditions of the Nammal Formation at the time of deposition in the Salt Range region. (author)

Comprehensive analysis of tropomyosin isoforms in skeletal muscles by top-down proteomics.

Science.gov (United States)

Jin, Yutong; Peng, Ying; Lin, Ziqing; Chen, Yi-Chen; Wei, Liming; Hacker, Timothy A; Larsson, Lars; Ge, Ying

2016-04-01

Mammalian skeletal muscles are heterogeneous in nature and are capable of performing various functions. Tropomyosin (Tpm) is a major component of the thin filament in skeletal muscles and plays an important role in controlling muscle contraction and relaxation. Tpm is known to consist of multiple isoforms resulting from different encoding genes and alternative splicing, along with post-translational modifications. However, a systematic characterization of Tpm isoforms in skeletal muscles is still lacking. Therefore, we employed top-down mass spectrometry (MS) to identify and characterize Tpm isoforms present in different skeletal muscles from multiple species, including swine, rat, and human. Our study revealed that Tpm1.1 and Tpm2.2 are the two major Tpm isoforms in swine and rat skeletal muscles, whereas Tpm1.1, Tpm2.2, and Tpm3.12 are present in human skeletal muscles. Tandem MS was utilized to identify the sequences of the major Tpm isoforms. Furthermore, quantitative analysis revealed muscle-type specific differences in the abundance of un-modified and modified Tpm isoforms in rat and human skeletal muscles. This study represents the first systematic investigation of Tpm isoforms in skeletal muscles, which not only demonstrates the capabilities of top-down MS for the comprehensive characterization of skeletal myofilament proteins but also provides the basis for further studies on these Tpm isoforms in muscle-related diseases.

Dentoskeletal Overjet Measurements of Iraqi Adult Sample with Different Skeletal Jaw Relationship

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Shahbaa A Mohammed

2017-11-01

Full Text Available Background: Many attempts were done to develop a method that actually reflects the sagittal jaw discrepancies without depending on cranial landmarks or dental occlusion. This study aimed to use one of these methods (dentoskeletal overjet for assessing the sagittal jaw relationships of Iraqi adult sample with different skeletal jaw relationship. Materials and method: The sample consisted of 90 digital true lateral cephalometric radiographs of Iraqi individuals with no previous orthodontic treatment. Cephalometric analysis of skeletal sagittal jaw relationship -ANB angle, beta angle and Wits appraisal- will perform for everyone to divide the sample into three groups (skeletal class I, II, III for which the dentoskeletal overjet will be measured. All cephalometric measurements will be done using AutoCAD. Results: Descriptive statistics of all variables with different skeletal jaw relationship showed that mean values of dentoskeletal overjet were (1.15, 3.91 and –2.01 mm for skeletal class I, class II and class III jaw relationship respectively. Accurate reproducibility of dentoskeletal overjet in assessment of jaw skeletal relationship showed that the lowest value was for assessment of skeletal class III jaw relationship (73% and the value for assessment of both skeletal class I and class II was higher (93%. Conclusions: Dentoskeletal overjet could be utilized in accurate representation of skeletal jaw relationship.

Skeletal Muscle Angiogenesis and Its Relation to Insulin Sensitivity

DEFF Research Database (Denmark)

Lindqvist, Anna Maria Charlotte K

mediator of angiogenesis) are reduced in insulin resistant individuals. Exercise training can improve skeletal muscle capillarization and the angiogenic potential and physical activity has also been proven to enhance muscle insulin sensitivity. Increased skeletal muscle capillarization is associated......) or by overexpression of VEGF-A in the tibialis anterior muscle (transfection; study II) and the effect of the increased muscle capillarization on muscle insulin sensitivity was examined. In study I skeletal muscle specific angiogenesis was induced by administering an α1-adrenergic antagonist (prazosin) to healthy...

Deletion of skeletal muscle SOCS3 prevents insulin resistance in obesity

DEFF Research Database (Denmark)

Beck Jørgensen, Sebastian; O'Neill, Hayley M; Sylow, Lykke

2013-01-01

Obesity is associated with chronic low-grade inflammation that contributes to defects in energy metabolism and insulin resistance. Suppressor of cytokine signaling (SOCS)-3 expression is increased in skeletal muscle of obese humans. SOCS3 inhibits leptin signaling in the hypothalamus and insulin...... of hyperinsulinemia and insulin resistance because of enhanced skeletal muscle insulin receptor substrate 1 (IRS1) and Akt phosphorylation that resulted in increased skeletal muscle glucose uptake. These data indicate that skeletal muscle SOCS3 does not play a critical role in regulating muscle development or energy...... expenditure, but it is an important contributing factor for inhibiting insulin sensitivity in obesity. Therapies aimed at inhibiting SOCS3 in skeletal muscle may be effective in reversing obesity-related glucose intolerance and insulin resistance....

Bone marrow mesenchymal cells improve muscle function in a skeletal muscle re-injury model.

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Bruno M Andrade

Full Text Available Skeletal muscle injury is the most common problem in orthopedic and sports medicine, and severe injury leads to fibrosis and muscle dysfunction. Conventional treatment for successive muscle injury is currently controversial, although new therapies, like cell therapy, seem to be promise. We developed a model of successive injuries in rat to evaluate the therapeutic potential of bone marrow mesenchymal cells (BMMC injected directly into the injured muscle. Functional and histological assays were performed 14 and 28 days after the injury protocol by isometric tension recording and picrosirius/Hematoxilin & Eosin staining, respectively. We also evaluated the presence and the fate of BMMC on treated muscles; and muscle fiber regeneration. BMMC treatment increased maximal skeletal muscle contraction 14 and 28 days after muscle injury compared to non-treated group (4.5 ± 1.7 vs 2.5 ± 0.98 N/cm2, p<0.05 and 8.4 ± 2.3 vs. 5.7 ± 1.3 N/cm2, p<0.05 respectively. Furthermore, BMMC treatment increased muscle fiber cross-sectional area and the presence of mature muscle fiber 28 days after muscle injury. However, there was no difference in collagen deposition between groups. Immunoassays for cytoskeleton markers of skeletal and smooth muscle cells revealed an apparent integration of the BMMC within the muscle. These data suggest that BMMC transplantation accelerates and improves muscle function recovery in our extensive muscle re-injury model.

Exercise Promotes Healthy Aging of Skeletal Muscle

DEFF Research Database (Denmark)

Cartee, Gregory D; Hepple, Russell T; Bamman, Marcas M

2016-01-01

caused by diseases and lifestyle factors. Secondary aging can exacerbate deficits in mitochondrial function and muscle mass, concomitant with the development of skeletal muscle insulin resistance. Exercise opposes deleterious effects of secondary aging by preventing the decline in mitochondrial...... respiration, mitigating aging-related loss of muscle mass and enhancing insulin sensitivity. This review focuses on mechanisms by which exercise promotes "healthy aging" by inducing modifications in skeletal muscle....

Effect of light and brine shrimp on skeletal δ 13C in the Hawaiian coral Porites compressa: a tank experiment

Science.gov (United States)

Grottoli, Andréa G.

2002-06-01

Previous experimental fieldwork showed that coral skeletal δ13C values decreased when solar intensity was reduced, and increased in the absence of zooplankton. However, actual seasonal changes in solar irradiance levels are typically less pronounced than those used in the previous experiment and the effect of increases in the consumption of zooplankton in the coral diet on skeletal δ13C remains relatively unknown. In the present study, the effects of four different light and heterotrophy regimes on coral skeletal δ13C values were measured. Porites compressa corals were grown in outdoor flow-through tanks under 112%, 100%, 75%, and 50% light conditions at the Hawaii Institute of Marine Biology, Hawaii. In addition, corals were fed either zero, low, medium, or high concentrations of brine shrimp. Decreases in light from 100% resulted in significant decreases in δ13C that is most likely due to a corresponding decrease in photosynthesis. Increases in light to 112% also resulted in a decrease in δ13C values. This latter response may be a consequence of photoinhibition. The overall curved response in δ13C values was described by a significant quadratic function. Increases in brine shrimp concentrations resulted in increased skeletal δ13C levels. This unexpected outcome appears to be attributable to enhanced nitrogen supply associated with the brine shrimp diet which led to increased zooxanthellae concentrations, increased photosynthesis rates, and thus increased δ13C values. This result highlights the potential influence of nutrients from heterotrophically acquired carbon in maintaining the zooxanthellae-host symbiosis in balance. In addition, evidence is presented that suggests that coral skeletal growth and δ13C are decoupled. These results increase our knowledge of how light and heterotrophy affects the δ13C of coral skeletons.

Biological and Climate Controls on North Atlantic Marine Carbon Dynamics Over the Last Millennium: Insights From an Absolutely Dated Shell-Based Record From the North Icelandic Shelf

Science.gov (United States)

Reynolds, D. J.; Hall, I. R.; Scourse, J. D.; Richardson, C. A.; Wanamaker, A. D.; Butler, P. G.

2017-12-01

Given the rapid increase in atmospheric carbon dioxide concentrations (pCO2) over the industrial era, there is a pressing need to construct long-term records of natural carbon cycling prior to this perturbation and to develop a more robust understanding of the role the oceans play in the sequestration of atmospheric carbon. Here we reconstruct the past biological and climate controls on the carbon isotopic (δ13Cshell) composition of the North Icelandic shelf waters over the last millennium, derived from the shells of the long-lived marine bivalve mollusk Arctica islandica. Variability in the annually resolved δ13Cshell record is dominated by multidecadal variability with a negative trend (-0.003 ± 0.002‰ yr-1) over the industrial era (1800-2000 Common Era). This trend is consistent with the marine Suess effect brought about by the sequestration of isotopically light carbon (δ13C of CO2) derived from the burning of fossil fuels. Comparison of the δ13Cshell record with Contemporaneous proxy archives, over the last millennium, and instrumental data over the twentieth century, highlights that both biological (primary production) and physical environmental factors, such as relative shifts in the proportion of Subpolar Mode Waters and Arctic Intermediate Waters entrained onto the North Icelandic shelf, atmospheric circulation patterns associated with the winter North Atlantic Oscillation, and sea surface temperature and salinity of the subpolar gyre, are the likely mechanisms that contribute to natural variations in seawater δ13C variability on the North Icelandic shelf. Contrasting δ13C fractionation processes associated with these biological and physical mechanisms likely cause the attenuated marine Suess effect signal at this locality.

Calprotectin is released from human skeletal muscle tissue during exercise

DEFF Research Database (Denmark)

Mortensen, Ole Hartvig; Andersen, Kasper; Fischer, Christian

2008-01-01

Skeletal muscle has been identified as a secretory organ. We hypothesized that IL-6, a cytokine secreted from skeletal muscle during exercise, could induce production of other secreted factors in skeletal muscle. IL-6 was infused for 3 h into healthy young males (n = 7) and muscle biopsies obtained...... in skeletal muscle following IL-6 infusion compared to controls. Furthermore, S100A8 and S100A9 mRNA levels were up-regulated 5-fold in human skeletal muscle following cycle ergometer exercise for 3 h at approximately 60% of in young healthy males (n = 8). S100A8 and S100A9 form calprotectin, which is known...... as an acute phase reactant. Plasma calprotectin increased 5-fold following acute cycle ergometer exercise in humans, but not following IL-6 infusion. To identify the source of calprotectin, healthy males (n = 7) performed two-legged dynamic knee extensor exercise for 3 h with a work load of approximately 50...

Osteopoikilosis: A Sign Mimicking Skeletal Metastases in a Cancer Patient

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Hamid Nasrolahi

2011-01-01

Full Text Available Osteopoikilosis is a rare benign osteosclerotic bone disorder that may be misdiagnosed as skeletal metastases. Here we describe a case of coincidental breast cancer and osteopoikilosis mimicking skeletal metastases. A 41-year-old woman underwent right modified radical mastectomy in April 2007. Twenty-eight months after initial treatment,the patient complained of bilateral knee and foot pain. Plain X-rays of the feet and knees showed multiple well-defined osteosclerotic lesions. According to the radiographic appearance, the most likely differential diagnoses included skeletal metastases from breast cancer and osteopoikilosis. A whole-body bone scintigraphy showed no increase in uptake by the sclerotic lesions, and serum lactic dehydrogenase, carcinoembryonic antigen, alkaline phosphatase and cancer antigen 15-3 were not elevated. We therefore diagnosed the patient’s skeletal lesions as osteopoikilosis. This case and ourliterature review suggest that the radiographic appearance of osteopoikilosis may mimic or mask skeletal metastases, potentially leading to misdiagnosis in patients with cancer.

Coral skeletal {delta}{sup 15}N reveals isotopic traces of an agricultural revolution

Energy Technology Data Exchange (ETDEWEB)

Marion, Guy S. [Department of Biological Sciences, Stanford University, Stanford, CA 94305 (United States)]. E-mail: g.marion@uq.edu.au; Dunbar, Robert B. [Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305 (United States); Mucciarone, David A. [Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305 (United States); Kremer, James N. [Department of Marine Sciences, University of Connecticut at Avery Point, Groton, CT 06340 (United States); Lansing, J. Stephen [Department of Anthropology, University of Arizona, Tucson, AZ 85721 (United States); Arthawiguna, Alit [Installation for Agricultural Research (IP 2TP), Kotak Pos 3480, Denpasar, Bali (Indonesia)

2005-09-01

This study introduces a new method of tracing the history of nutrient loading in coastal oceans via {delta}{sup 15}N analysis of organic nitrogen preserved in the skeleton of the massive Porites coral. Four coral cores were collected in Bali, Indonesia, from reefs exposed to high levels of fertilizers in agricultural run-off, from lagoonal corals impacted by sewage, and from a reef located 30 km offshore. Skeletal {delta}{sup 15}N in the agriculturally exposed coral declined from 10.7 {+-} 0.4 per mille in 1970-1971, when synthetic fertilizers (-0.8 per mille {+-} 0.2 per mille ) were introduced to Bali, to a depleted 'anthropogenic' baseline of 3.5 per mille {+-} 0.4% in the mid-1990s. {delta}{sup 15}N values were negatively correlated with rainfall, suggesting that marine {delta}{sup 15}N lowers during flood-born influxes of waste fertilizers. Reef cores exposed to untreated sewage in terrestrial discharge were enriched (7.8 and 7.3 {+-} 0.4 per mille ), while the offshore core reflected background oceanic signals (6.2 {+-} 0.4 per mille). {delta}{sup 15}N, N concentration, and C:N systematics indicate that the N isotopic composition of skeletal organic matter was generally well preserved over 30 years. We suggest that skeletal organic {delta}{sup 15}N can serve as a recorder of past nitrogen sources. In Bali, this tracer suggests that the intensification of Western style agricultural practices since 1970 are contributing to the degradation of coastal coral reefs.

Occipital projections in the skeletal dysplasias

International Nuclear Information System (INIS)

Takamine, Yuji; Field, Fiona M.; Lachman, Ralph S.; Rimoin, David L.

2004-01-01

Occipital projections of the cranium have been reported in a number of skeletal dysplasias and syndromes. We observed two cases of atelosteogenesis type I with a bony occipital projection. This finding has neither been noted nor reported in any form of atelosteogenesis. This led us to search the International Skeletal Dysplasia Registry for occipital projections, and we found them in four other syndromes in which they had not been reported. Thus occipital spurs are a non-diagnostic feature that can be found in at least ten distinct disorders as well as a normal variant. (orig.)

Regulation of the skeletal muscle blood flow in humans

DEFF Research Database (Denmark)

Mortensen, Stefan; Saltin, Bengt

2014-01-01

In humans, skeletal muscle blood flow is regulated by an interaction between several locally formed vasodilators including nitric oxide (NO) and prostaglandins. In plasma, ATP is a potent vasodilator that stimulates the formation of NO and prostaglandins and very importantly can offset local...... concentration does not increase during exercise. In the skeletal muscle interstitium, there is a marked increase in the concentration of ATP and adenosine and this increase is tightly coupled to the increase in blood flow. The sources of interstitial ATP and adenosine are thought to be skeletal muscle cells...... hyperaemia whereas the role of ATP remains uncertain due to lack of specific purinergic receptor blockers for human use. The purpose of this review is to address the interaction between vasodilator systems and to discuss the multiple proposed roles of ATP in human skeletal muscle blood flow regulation...

Skeletal muscle apolipoprotein B expression reduces muscular triglyceride accumulation

DEFF Research Database (Denmark)

Bartels, Emil D; Ploug, Thorkil; Størling, Joachim

2014-01-01

Abstract Background. Lipid accumulation in skeletal muscle is associated with impaired insulin sensitivity in type 2 diabetes. In cardiac myocytes, lipoprotein secretion controlled by apolipoproteinB (apoB) and microsomal triglyceride transfer protein (MTP) affects lipid homeostasis. Design. In t...... accumulation and attenuates peripheral insulin resistance in obese mice........ In this study, we investigated whether expression of a human apoB transgene affects triglyceride accumulation and insulin sensitivity in skeletal muscle in fat fed obese mice. Results. Expression of apoB and MTP mRNA and the human apoB transgene was seen in skeletal muscle of the transgene mice. Human apo......Abstract Background. Lipid accumulation in skeletal muscle is associated with impaired insulin sensitivity in type 2 diabetes. In cardiac myocytes, lipoprotein secretion controlled by apolipoproteinB (apoB) and microsomal triglyceride transfer protein (MTP) affects lipid homeostasis. Design...

Neuromuscular junction formation between human stem cell-derived motoneurons and human skeletal muscle in a defined system.

Science.gov (United States)

Guo, Xiufang; Gonzalez, Mercedes; Stancescu, Maria; Vandenburgh, Herman H; Hickman, James J

2011-12-01

Functional in vitro models composed of human cells will constitute an important platform in the next generation of system biology and drug discovery. This study reports a novel human-based in vitro Neuromuscular Junction (NMJ) system developed in a defined serum-free medium and on a patternable non-biological surface. The motoneurons and skeletal muscles were derived from fetal spinal stem cells and skeletal muscle stem cells. The motoneurons and skeletal myotubes were completely differentiated in the co-culture based on morphological analysis and electrophysiology. NMJ formation was demonstrated by phase contrast microscopy, immunocytochemistry and the observation of motoneuron-induced muscle contractions utilizing time-lapse recordings and their subsequent quenching by d-Tubocurarine. Generally, functional human based systems would eliminate the issue of species variability during the drug development process and its derivation from stem cells bypasses the restrictions inherent with utilization of primary human tissue. This defined human-based NMJ system is one of the first steps in creating functional in vitro systems and will play an important role in understanding NMJ development, in developing high information content drug screens and as test beds in preclinical studies for spinal or muscular diseases/injuries such as muscular dystrophy, Amyotrophic lateral sclerosis and spinal cord repair. Copyright © 2011 Elsevier Ltd. All rights reserved.

The magnesium isotope record of cave carbonate archives

Science.gov (United States)

Riechelmann, S.; Buhl, D.; Schröder-Ritzrau, A.; Riechelmann, D. F. C.; Richter, D. K.; Vonhof, H. B.; Wassenburg, J. A.; Geske, A.; Spötl, C.; Immenhauser, A.

2012-11-01

Here we explore the potential of magnesium (δ26Mg) isotope time-series data as continental climate proxies in speleothem calcite archives. For this purpose, a total of six Pleistocene and Holocene stalagmites from caves in Germany, Morocco and Peru and two flowstones from a cave in Austria were investigated. These caves represent the semi-arid to arid (Morocco), the warm-temperate (Germany), the equatorial-humid (Peru) and the cold-humid (Austria) climate zones. Changes in the calcite magnesium isotope signature with time are compared against carbon and oxygen isotope records from these speleothems. Similar to other proxies, the non-trivial interaction of a number of environmental, equilibrium and disequilibrium processes governs the δ26Mg fractionation in continental settings. These include the different sources of magnesium isotopes such as rainwater or snow as well as soil and host rock, soil zone biogenic activity, shifts in silicate versus carbonate weathering ratios and residence time of water in the soil and karst zone. Pleistocene stalagmites from Morocco show the lowest mean δ26Mg values (GDA: -4.26 ± 0.07‰ and HK3: -4.17 ± 0.15‰), and the data are well explained in terms of changes in aridity over time. The Pleistocene to Holocene stalagmites from Peru show the highest mean value of all stalagmites (NC-A and NC-B δ26Mg: -3.96 ± 0.04‰) but only minor variations in Mg-isotope composition, which is consistent with the rather stable equatorial climate at this site. Holocene stalagmites from Germany (AH-1 mean δ26Mg: -4.01 ± 0.07‰; BU 4 mean δ26Mg: -4.20 ± 0.10‰) suggest changes in outside air temperature was the principal driver rather than rainfall amount. The alpine Pleistocene flowstones from Austria (SPA 52: -3.00 ± 0.73‰; SPA 59: -3.70 ± 0.43‰) are affected by glacial versus interglacial climate change with outside air temperature affecting soil zone activity and weathering balance. Several δ26Mg values of the Austrian and two

Proteomics of Skeletal Muscle: Focus on Insulin Resistance and Exercise Biology

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Atul S. Deshmukh

2016-02-01

Full Text Available Skeletal muscle is the largest tissue in the human body and plays an important role in locomotion and whole body metabolism. It accounts for ~80% of insulin stimulated glucose disposal. Skeletal muscle insulin resistance, a primary feature of Type 2 diabetes, is caused by a decreased ability of muscle to respond to circulating insulin. Physical exercise improves insulin sensitivity and whole body metabolism and remains one of the most promising interventions for the prevention of Type 2 diabetes. Insulin resistance and exercise adaptations in skeletal muscle might be a cause, or consequence, of altered protein expressions profiles and/or their posttranslational modifications (PTMs. Mass spectrometry (MS-based proteomics offer enormous promise for investigating the molecular mechanisms underlying skeletal muscle insulin resistance and exercise-induced adaptation; however, skeletal muscle proteomics are challenging. This review describes the technical limitations of skeletal muscle proteomics as well as emerging developments in proteomics workflow with respect to samples preparation, liquid chromatography (LC, MS and computational analysis. These technologies have not yet been fully exploited in the field of skeletal muscle proteomics. Future studies that involve state-of-the-art proteomics technology will broaden our understanding of exercise-induced adaptations as well as molecular pathogenesis of insulin resistance. This could lead to the identification of new therapeutic targets.

Leucine stimulation of skeletal muscle protein synthesis

International Nuclear Information System (INIS)

Layman, D.K.; Grogan, C.K.

1986-01-01

Previous work in this laboratory has demonstrated a stimulatory effect of leucine on skeletal muscle protein synthesis measured in vitro during catabolic conditions. Studies in other laboratories have consistently found this effect in diaphragm muscle, however, studies examining effects on nitrogen balance or with in vivo protein synthesis in skeletal muscle are equivocal. This experiment was designed to determine the potential of leucine to stimulate skeletal muscle protein synthesis in vivo. Male Sprague-Dawley rats weighing 200 g were fasted for 12 hrs, anesthetized, a jugular cannula inserted, and protein synthesis measured using a primed continuous infusion of 14 C-tyrosine. A plateau in specific activity was reached after 30 to 60 min and maintained for 3 hrs. The leucine dose consisted of a 240 umole priming dose followed by a continuous infusion of 160 umoles/hr. Leucine infusion stimulated protein synthesis in the soleus muscle (28%) and in the red (28%) and white portions (12%) of the gastrocnemius muscle compared with controls infused with only tyrosine. The increased rates of protein synthesis were due to increased incorporation of tyrosine into protein and to decreased specific activity of the free tyrosine pool. These data indicate that infusion of leucine has the potential to stimulate in vivo protein synthesis in skeletal muscles

Altered cross-bridge properties in skeletal muscle dystrophies

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Aziz eGuellich

2014-10-01

Full Text Available Force and motion generated by skeletal muscle ultimately depends on the cyclical interaction of actin with myosin. This mechanical process is regulated by intracellular Ca2+ through the thin filament-associated regulatory proteins i.e.; troponins and tropomyosin. Muscular dystrophies are a group of heterogeneous genetic affections characterized by progressive degeneration and weakness of the skeletal muscle as a consequence of loss of muscle tissue which directly reduces the number of potential myosin cross-bridges involved in force production. Mutations in genes responsible for skeletal muscle dystrophies have been shown to modify the function of contractile proteins and cross-bridge interactions. Altered gene expression or RNA splicing or post-translational modifications of contractile proteins such as those related to oxidative stress, may affect cross-bridge function by modifying key proteins of the excitation-contraction coupling. Micro-architectural change in myofilament is another mechanism of altered cross-bridge performance. In this review, we provide an overview about changes in cross-bridge performance in skeletal muscle dystrophies and discuss their ultimate impacts on striated muscle function.

Using Human Induced Pluripotent Stem Cells to Model Skeletal Diseases.

Science.gov (United States)

Barruet, Emilie; Hsiao, Edward C

2016-01-01

Musculoskeletal disorders affecting the bones and joints are major health problems among children and adults. Major challenges such as the genetic origins or poor diagnostics of severe skeletal disease hinder our understanding of human skeletal diseases. The recent advent of human induced pluripotent stem cells (human iPS cells) provides an unparalleled opportunity to create human-specific models of human skeletal diseases. iPS cells have the ability to self-renew, allowing us to obtain large amounts of starting material, and have the potential to differentiate into any cell types in the body. In addition, they can carry one or more mutations responsible for the disease of interest or be genetically corrected to create isogenic controls. Our work has focused on modeling rare musculoskeletal disorders including fibrodysplasia ossificans progressive (FOP), a congenital disease of increased heterotopic ossification. In this review, we will discuss our experiences and protocols differentiating human iPS cells toward the osteogenic lineage and their application to model skeletal diseases. A number of critical challenges and exciting new approaches are also discussed, which will allow the skeletal biology field to harness the potential of human iPS cells as a critical model system for understanding diseases of abnormal skeletal formation and bone regeneration.

Stable and radioactive carbon in Indian soils: implications to soil carbon dynamics

International Nuclear Information System (INIS)

Laskar, A.H.; Yadava, M.G.; Ramesh, R.

2011-01-01

Radiocarbon is a very useful tool to study soil carbon dynamic. The mean residence time of SOC in Indian soils is about a century at the top 0-15 cm, increases linearly to reach values ranging from 2000 to 4000 yrs at a depth of 100 cm. It mainly depends on the clay content indicating that the clay is the main governing factor for SOC stabilization. Stable carbon and oxygen isotopes in soil carbonates and SOC are good proxies for paleoclimate and paleovegetation reconstruction. The present day sub-humid climate in the lower Narmada valley has been established prior to ∼ 3 ka. Two comparatively arid phases around 2.1 and 1.3 ka are recorded by oxygen isotopes of soil carbonates; consistent with other proxy records showing its regional significance

Skeletal Aging and Osteoporosis Biomechanics and Mechanobiology

CERN Document Server

2013-01-01

The focus of this book is on mechanical aspects of skeletal fragility related to aging and osteoporosis. Topics include: Age-related changes in trabecular structure and strength; age-related changes in cortical material properties; age-related changes in whole-bone structure; predicting bone strength and fracture risk using image-based methods and finite element analysis; animal models of osteoporosis and aging; age-related changes in skeletal mechano responsiveness; exercise and physical interventions for osteoporosis.

Effects of the belt electrode skeletal muscle electrical stimulation system on lower extremity skeletal muscle activity: Evaluation using positron emission tomography.

Science.gov (United States)

Numata, Hitoaki; Nakase, Junsuke; Inaki, Anri; Mochizuki, Takafumi; Oshima, Takeshi; Takata, Yasushi; Kinuya, Seigo; Tsuchiya, Hiroyuki

2016-01-01

Lower-extremity muscle weakness in athletes after lower limb trauma or surgery can hinder their return to sports, and the associated muscle atrophy may lead to deterioration in performance after returning to sports. Recently, belt electrode skeletal muscle electrical stimulation (B-SES) which can contract all the lower limb skeletal muscles simultaneously was developed. However, no study has evaluated skeletal muscle activity with B-SES. Since only superficial muscles as well as a limited number of muscles can be investigated using electromyography, we investigated whether positron emission tomography (PET) can evaluate the activity of all the skeletal muscles in the body simultaneously. The purpose of this study was to evaluate the effectiveness of the B-SES system using PET. Twelve healthy males (mean age, 24.3 years) were divided into two groups. The subjects in the control group remained in a sitting position for 10 min, and [(18)F] fluorodeoxyglucose (FDG) was intravenously injected. In the exercise group, subjects exercised using the B-SES system for 20 min daily for three consecutive days as a pre-test exercise. On the measurement day, they exercised for 10 min, received an injection of FDG, and exercised for another 10 min. PET-computed tomography images were obtained in each group 60 min after the FDG injection. Regions of interest were drawn in each lower-extremity muscle. We compared each skeletal muscle metabolism using the standardized uptake value. In the exercise group, FDG accumulation in the gluteus maximus, gluteus medius, gluteus minimus, quadriceps femoris, sartorius, and hamstrings was significantly higher than the muscles in the control (P skeletal muscle activity of the gluteal muscles as well as the most lower-extremity muscles simultaneously. Copyright © 2015 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Bone scintigraphy in children with obscure skeletal pain

International Nuclear Information System (INIS)

Majd, Massoud

1979-01-01

In a group of 82 children with focal or generalized skeletal pain of obscure etiology, the radionuclide skeletal scintigraphy was the only, or the most informative, clue to the diagnosis of a variety of benign and malignant conditions. It is strongly recommended that any unexplained bone or joint pain in children be evaluated by this non-invasive technique [fr

Redox regulation of calcium release in skeletal and cardiac muscle

Directory of Open Access Journals (Sweden)

CECILIA HIDALGO

2002-01-01

Full Text Available In skeletal and cardiac muscle cells, specific isoforms of the Ryanodine receptor channels mediate Ca2+ release from the sarcoplasmic reticulum. These channels are highly susceptible to redox modifications, which regulate channel activity. In this work, we studied the effects of Ca2+ (endogenous agonist and Mg2+ (endogenous inhibitor on the kinetics of Ca2+ release from sarcoplasmic reticulum vesicles isolated from skeletal or cardiac mammalian muscle. Native skeletal vesicles exhibited maximal stimulation of release kinetics by 10-20 µM [Ca2+], whereas in native cardiac vesicles, maximal stimulation of release required only 1 µM [Ca2+]. In 10 µM [Ca2+], free [Mg2+] < 0.1 mM produced marked inhibition of release from skeletal vesicles but free [Mg2+] ­ 0.8 mM did not affect release from cardiac vesicles. Incubation of skeletal or cardiac vesicles with the oxidant thimerosal increased their susceptibility to stimulation by Ca2+ and decreased the inhibitory effect of Mg2+ in skeletal vesicles. Sulfhydryl-reducing agents fully reversed the effects of thimerosal. The endogenous redox species, glutathione disulfide and S-nitrosoglutathione, also stimulated release from skeletal sarcoplasmic reticulum vesicles. In 10 µM [Ca2+], 35S-nitrosoglutathione labeled a protein fraction enriched in release channels through S-glutathiolation. Free [Mg2+] 1 mM or decreasing free [Ca2+] to the nM range prevented this reaction. Possible physiological and pathological consequences of redox modification of release channels on Ca2+ signaling in heart and muscle cells are discussed

Carbon fiber on polyimide ultra-microelectrodes

Science.gov (United States)

Gillis, Winthrop F.; Lissandrello, Charles A.; Shen, Jun; Pearre, Ben W.; Mertiri, Alket; Deku, Felix; Cogan, Stuart; Holinski, Bradley J.; Chew, Daniel J.; White, Alice E.; Otchy, Timothy M.; Gardner, Timothy J.

2018-02-01

Objective. Most preparations for making neural recordings degrade over time and eventually fail due to insertion trauma and reactive tissue response. The magnitudes of these responses are thought to be related to the electrode size (specifically, the cross-sectional area), the relative stiffness of the electrode, and the degree of tissue tolerance for the material. Flexible carbon fiber ultra-microelectrodes have a much smaller cross-section than traditional electrodes and low tissue reactivity, and thus may enable improved longevity of neural recordings in the central and peripheral nervous systems. Only two carbon fiber array designs have been described previously, each with limited channel densities due to limitations of the fabrication processes or interconnect strategies. Here, we describe a method for assembling carbon fiber electrodes on a flexible polyimide substrate that is expected to facilitate the construction of high-density recording and stimulating arrays. Approach. Individual carbon fibers were aligned using an alignment tool that was 3D-printed with sub-micron resolution using direct laser writing. Indium deposition on the carbon fibers, followed by low-temperature microsoldering, provided a robust and reliable method of electrical connection to the polyimide interconnect. Main results. Spontaneous multiunit activity and stimulation-evoked compound responses with SNR  >10 and  >120, respectively, were recorded from a small (125 µm) peripheral nerve. We also improved the typically poor charge injection capacity of small diameter carbon fibers by electrodepositing 100 nm-thick iridium oxide films, making the carbon fiber arrays usable for electrical stimulation as well as recording. Significance. Our innovations in fabrication technique pave the way for further miniaturization of carbon fiber ultra-microelectrode arrays. We believe these advances to be key steps to enable a shift from labor intensive, manual assembly to a more automated

Comparison of interradicular distances and cortical bone thickness in Thai patients with class I and class II skeletal patterns using cone-beam computed tomography

Energy Technology Data Exchange (ETDEWEB)

Khumsarn, Nattida [Dental Division of Lamphun Hospital, Lamphun (Thailand); Patanaporn, Virush; Janhom, Apirum; Jotikasthira, Dhirawat [Faculty of Dentistry, Chiang Mai University, Chiang Mai (Thailand)

2016-06-15

This study evaluated and compared interradicular distances and cortical bone thickness in Thai patients with Class I and Class II skeletal patterns, using cone-beam computed tomography (CBCT). Pretreatment CBCT images of 24 Thai orthodontic patients with Class I and Class II skeletal patterns were included in the study. Three measurements were chosen for investigation: the mesiodistal distance between the roots, the width of the buccolingual alveolar process, and buccal cortical bone thickness. All distances were recorded at five different levels from the cementoenamel junction (CEJ). Descriptive statistical analysis and t-tests were performed, with the significance level for all tests set at p<0.05. Patients with a Class II skeletal pattern showed significantly greater maxillary mesiodistal distances (between the first and second premolars) and widths of the buccolingual alveolar process (between the first and second molars) than Class I skeletal pattern patients at 10 mm above the CEJ. The maxillary buccal cortical bone thicknesses between the second premolar and first molar at 8 mm above the CEJ in Class II patients were likewise significantly greater than in Class I patients. Patients with a Class I skeletal pattern showed significantly wider mandibular buccolingual alveolar processes than did Class II patients (between the first and second molars) at 4, 6, and 8 mm below the CEJ. In both the maxilla and mandible, the mesiodistal distances, the width of the buccolingual alveolar process, and buccal cortical bone thickness tended to increase from the CEJ to the apex in both Class I and Class II skeletal patterns.

Comparison of interradicular distances and cortical bone thickness in Thai patients with class I and class II skeletal patterns using cone-beam computed tomography

International Nuclear Information System (INIS)

Khumsarn, Nattida; Patanaporn, Virush; Janhom, Apirum; Jotikasthira, Dhirawat

2016-01-01

This study evaluated and compared interradicular distances and cortical bone thickness in Thai patients with Class I and Class II skeletal patterns, using cone-beam computed tomography (CBCT). Pretreatment CBCT images of 24 Thai orthodontic patients with Class I and Class II skeletal patterns were included in the study. Three measurements were chosen for investigation: the mesiodistal distance between the roots, the width of the buccolingual alveolar process, and buccal cortical bone thickness. All distances were recorded at five different levels from the cementoenamel junction (CEJ). Descriptive statistical analysis and t-tests were performed, with the significance level for all tests set at p<0.05. Patients with a Class II skeletal pattern showed significantly greater maxillary mesiodistal distances (between the first and second premolars) and widths of the buccolingual alveolar process (between the first and second molars) than Class I skeletal pattern patients at 10 mm above the CEJ. The maxillary buccal cortical bone thicknesses between the second premolar and first molar at 8 mm above the CEJ in Class II patients were likewise significantly greater than in Class I patients. Patients with a Class I skeletal pattern showed significantly wider mandibular buccolingual alveolar processes than did Class II patients (between the first and second molars) at 4, 6, and 8 mm below the CEJ. In both the maxilla and mandible, the mesiodistal distances, the width of the buccolingual alveolar process, and buccal cortical bone thickness tended to increase from the CEJ to the apex in both Class I and Class II skeletal patterns

Photothermal imaging of skeletal muscle mitochondria.

Science.gov (United States)

Tomimatsu, Toru; Miyazaki, Jun; Kano, Yutaka; Kobayashi, Takayoshi

2017-06-01

The morphology and topology of mitochondria provide useful information about the physiological function of skeletal muscle. Previous studies of skeletal muscle mitochondria are based on observation with transmission, scanning electron microscopy or fluorescence microscopy. In contrast, photothermal (PT) microscopy has advantages over the above commonly used microscopic techniques because of no requirement for complex sample preparation by fixation or fluorescent-dye staining. Here, we employed the PT technique using a simple diode laser to visualize skeletal muscle mitochondria in unstained and stained tissues. The fine mitochondrial network structures in muscle fibers could be imaged with the PT imaging system, even in unstained tissues. PT imaging of tissues stained with toluidine blue revealed the structures of subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondria and the swelling behavior of mitochondria in damaged muscle fibers with sufficient image quality. PT image analyses based on fast Fourier transform (FFT) and Grey-level co-occurrence matrix (GLCM) were performed to derive the characteristic size of mitochondria and to discriminate the image patterns of normal and damaged fibers.

Mechanisms of internal emitter skeletal toxicity

International Nuclear Information System (INIS)

Jee, W.S.S.

1985-01-01

The purpose of this program is to determine the mechanisms for the induction of skeletal cancers in dogs and man by α-emitting bone-seeking radionuclides from the nuclear fuel cycle. The role of microdistribution of radium-226 and plutonium-239, bone metabolism, bone cell turnover, and localized bone cell dosimetry in bone can induction will be determined. The osteogenic cell dose will be measured in dogs to develop better quantitative dose response information. Skeletal carcinogenesis models will be developed by correlating the local dosimetry, tumor site and incidence, age-dependent skeletal biology (bone morphometry, bone cell at risk, bone cell turnover, residence time and fate, remodeling rate, growth pattern and rate, hormonal influences, manipulation of bone cell populations of the bone modeling and remodeling systems, etc.). The authors will test the hypothesis that the frequency of osteosarcomas is proportional to the average dose delivered to cells at risk. They will also attempt to explain experimentally found toxicity ratios between volume- and bone surface-seeking radionuclides on the basis of radiation dose ratios

Skeletal metastases from primary hepatocellular carcinoma

International Nuclear Information System (INIS)

Kim, So Sun; Huh, Jin Do; Kim, Ho Joon; Chun, Byung Hee; Joh, Young Duk; Chang, Hee Kyung; Huh, Man Ha

1988-01-01

In order to detect and to evaluate the frequency, the distribution, and the radiological findings of skeletal metastases from hepatocellular carcinoma, the authors retrospectively analyzed radiographic, scintigraphic, and CT findings of 257 patients with hepatocellular carcinoma. The results were as follows: 1. Skeletal metastases were demonstrated in 21 patients (8.2%). 2. Frequent symptoms were pain, limitation of motion, paralysis, and mass. In nine of them the initial symptoms were due to skeletal metastases. 3. The common sites of metastases were spine (13 cases), ribs (8 cases), pelvis (8 cases) and femur (6 cases). Humerus, skull and sternum were also frequently involved. 4. Plain film findings were purely osteolytic in all cases and pathologic fractures were noted in 5 cases. 5. The lesions appear expansible in 7 cases, and 4 of them showed associated soft tissue masses on CT scans. 6. Bone scans were performed in 13 cases of them and showed increased radiotracer uptake in all. 7. Angiographic studies of 3 cases showed hypervascularity of the metastatic lesions as well as the primary hepatic tumor.

CT findings in skeletal cystic echinococcosis

Energy Technology Data Exchange (ETDEWEB)

Tuezuen, M.; Hekimoglu, B. [Social Security Hospital, Ankara (Turkey). Dept. of Radiology

2002-09-01

Purpose: To evaluate the CT findings of skeletal cystic echinococcosis. Material and Methods: CT findings of 7 patients with pathologically confirmed skeletal cystic echinococcosis were evaluated. Results: There were 4 men and 3 women, aged 36-75 years. Hydatid cysts were located in the spine (n=2), a rib (n=3), the pelvis and a vertebra (n=1), the pelvis and the left femur (n=1). The size of the lesions varied from 1 cm to 15 cm. CT showed well defined, single or multiple cystic lesions with no contrast enhancement, no calcification, no daughter cysts, and no germinal membrane detachment. The cystic lesion had a honeycomb appearance in 2 cases, there was pathologic fracture in 2 cases, bone expansion in 5 cases, cortical thinning in 6 cases, cortical destruction in 6 cases, bone sclerosis in 1 case, and soft tissue extension in 6 cases. Conclusion: Preoperative differential diagnosis of skeletal cystic lesions should include cystic echinococcosis, especially in endemic areas, since this diagnosis may easily be missed unless kept in mind.

Skeletal Muscle Metastasis from a Cecal Mucinous Adenocarcinoma: A Case Report

International Nuclear Information System (INIS)

Lee, Dong Hyun; Lee, Young Hwan; Jung, Kyung Jae; Park, Young Chan; Kim, Ho Kyun; Cho, Seung Hyun

2008-01-01

Skeletal muscle metastasis is a relatively rare finding in the setting of mucinous adenocarcinoma of the colon, and it typically exhibits nonspecific imaging findings. We report a case of a skeletal muscle metastasis originating from mucinous adenocarcinoma of the cecum. The skeletal lesion closely resembled intramuscular myxoma with regard to imaging findings, due to abundant mucin and internal calcification

Skeletal class III camouflage by mandibular incisor extraction: A case report

Directory of Open Access Journals (Sweden)

Janardhanan Kumaresan

2014-01-01

Full Text Available Treatment planning in orthodontics plays a key role in determining the successful treatment of any kind of malocclusion. Skeletal class III malocclusions are generally difficult to treat because of the complex nature of the skeletal and dental manifestations they produce. Mild to moderate skeletal class III malocclusions sometimes have an acceptable facial profile where orthodontic camouflage is possible. In this case report, camouflage of a mild skeletal class III is done by the extraction of a single mandibular incisor, which helped in maintaining the profile of the patient and also in the correction of crowding in the mandibular anterior region.

Assessing offsets between the δ13C of sedimentary components and the global exogenic carbon pool across early Paleogene carbon cycle perturbations

NARCIS (Netherlands)

Sluijs, A.; Dickens, G.R.

2012-01-01

Negative stable carbon isotope excursions (CIEs) across the Paleocene–Eocene thermal maximum (PETM; ∼56 Ma) range between 2‰ and 7‰, even after discounting sections with truncated records. Individual carbon isotope records differ in shape and magnitude from variations in the global exogenic carbon

A correlative study of dental age and skeletal maturation.

Science.gov (United States)

Sachan, Kiran; Sharma, Vijay Prakash; Tandon, Pradeep

2011-01-01

Skeletal age had been assessed by comparison between maturation of hand-wrist with stages of cervical vertebrae or canine calcification stages in past and this had been closely related to craniofacial growth. The importance of pubertal growth spurt in various types of orthodontic therapies is already established. Hence, this study was aimed to evaluate the relationship of skeletal maturity by hand-wrist with cervical vertebral maturation indicators and canine calcification stages. The study consisted of randomly selected 90 children from Lucknow population with 45 males (age range 10-13 years) and 45 females (age range 9-12 years). Lateral Cephalogram, hand-wrist x-ray, and periapical x-rays of maxillary and mandibular right canines were taken. Mean, standard deviation was calculated of different groups. Correlation was made among cervical vertebral maturation, hand wrist maturation, and canine calcification stages at various age groups. There was strong correlation between skeletal maturation indicator and cervical vertebral maturation indicator for both male (0.849) and female (0.932), whereas correlation between skeletal maturation indicator and canine calcification was good for both male and female (0.635, 0.891). It was concluded that cervical vertebral maturation indicator and canine calcification stages can also be used for assessing skeletal maturity.

FDG-PET/CT in Skeletal Muscle: Pitfalls and Pathologies.

Science.gov (United States)

Parida, Girish Kumar; Roy, Shambo Guha; Kumar, Rakesh

2017-07-01

FDG-PET/CT is an integral part of modern-day practice of medicine. By detecting increased cellular metabolism, FDG-PET/CT can help us detect infection, inflammatory disorders, or tumors, and also help us in prognostication of patients. However, one of the most important challenges is to correctly differentiate the abnormal uptake that is potentially pathologic from the physiological uptake. So while interpreting a PET/CT, one must be aware of normal biodistribution and different physiological variants of FDG uptake. Skeletal muscles constitute a large part of our body mass and one of the major users of glucose. Naturally, they are often the site of increased FDG uptake in a PET study. We as a nuclear medicine physician must be aware of all the pitfalls of increased skeletal muscle uptake to differentiate between physiological and pathologic causes. In this review, we have discussed the different causes and patterns of physiological FDG uptake in skeletal muscles. This knowledge of normal physiological variants of FDG uptake in the skeletal muscles is essential for differentiating pathologic uptake from the physiological ones. Also, we reviewed the role of FDG-PET/CT in various benign and malignant diseases involving skeletal muscle. Copyright © 2017 Elsevier Inc. All rights reserved.

Skeletal muscle wasting: new role of nonclassical renin-angiotensin system.

Science.gov (United States)

Cabello-Verrugio, Claudio; Rivera, Juan C; Garcia, Dominga

2017-05-01

Skeletal muscle can be affected by many physiological and pathological conditions that contribute to the development of muscle weakness, including skeletal muscle loss, inflammatory processes, or fibrosis. Therefore, research into therapeutic treatment alternatives or alleviation of these effects on skeletal muscle is of great importance. Recent studies have shown that angiotensin (1-7) [Ang-(1-7)] - a vasoactive peptide of the nonclassical axis in the renin-angiotensin system (RAS) - and its Mas receptor are expressed in skeletal muscle. Ang-(1-7), through its Mas receptor, prevents or diminishes deleterious effects induced by skeletal muscle disease or injury. Specifically, the Ang-(1-7)-Mas receptor axis modulates molecular mechanisms involved in muscle mass regulation, such as the ubiquitin proteasome pathway, the insulin-like growth factor type 1/Akt (protein kinase B) pathway, or myonuclear apoptosis, and also inflammation and fibrosis pathways. Although further research into this topic and the possible side effects of Ang-(1-7) is necessary, these findings are promising, and suggest that the Ang-(1-7)-Mas axis can be considered a possible therapeutic target for treating patients with muscular disorders.

Mollusc and brachiopod skeletal hardparts: Problematic archives of past seawater properties (Invited)

Science.gov (United States)

Immenhauser, A.; Schone, B. R.; Hoffmann, R.; Niedermayr, A.

2013-12-01

Biomineralized exo- or endoskeletons of fossil marine invertebrates are widespread and diverse components of the Phanerozoic rock record of Earth's past and present oceans. Exoskeletons serve as protection against environmental pressure or predators, whilst endoskeletons may act as support or serves as an attachment for muscles and ligaments and hence as a mechanism for transmitting muscular forces. Biogenic hardparts represent sophisticated products resulting from the hierarchical interaction of inorganic minerals (95%) and macromolecular organic matrix, forming commonly less than 5%. The significance of biogenic carbonate archives lies in the time-resolved growth-increments and their respective multi-proxy geochemical signatures that have been widely used to assess past oceanic seawater properties. We here compile and review published work dealing with crystallization pathways of skeletal hardparts secreted by molluscs (i.e., bivalves and cephalopods) as well as brachiopods as widely used archives of ancient neritic epeiric settings. Bivalves and cephalopods (e.g., extinct ammonoids and belemnites and extant Sepia, Nautilus and Spirula) all form accretionary calcitic, aragonitic or vateritic skeletal hardparts. Despite the fact that molluscs and brachiopods form part of very different branches of the animal phylogenetic tree, their biomineralization strategies are surprisingly similar. Our main focus lies in a critical assessment of the complex pathways of ions and aquo-complexes from their source (seawater) to the final product (biomineral). We do this as an attempt to critically test the commonly held hypothesis that many fossil shell hardparts precipitated, under favourable conditions and pending subsequent diagenetic alteration, in equilibrium with seawater. Two main observations stand out: (1) the present knowledge on pathways and mechanisms (e.g., ion channel trans-membrane or endocytosis and vesicle transport, precursor mineralogies etc.) is surprisingly

Magnetic resonance imaging of the skeletal musculature

Energy Technology Data Exchange (ETDEWEB)

Weber, Marc-Andre (ed.) [Univ. Hospital Heidelberg (Germany). Diagnostic and Intverventional Radiology

2014-07-01

Comprehensive overview of the value of cutting-edge MRI for the assessment of normal and diseased skeletal muscle. Presents research findings in respect of the role of modern morphological and functional MRI techniques. Provides examples of the added value provided by these techniques when evaluating muscular diseases. Although muscular diseases are a huge and heterogeneous group, in most cases of progressive disease the result is focal or general muscular weakness that presents as an unspecific symptom. Imaging techniques that offer differential diagnostic clues are therefore urgently needed. Despite this, MRI has to date often been assigned a subsidiary role in the diagnostic work-up of these diseases owing to the frequent inability of routine MRI protocols to detect pathognomonic findings. This situation is changing with the advent of modern MRI techniques that offer deeper insights into surrogate pathophysiologic parameters, such as muscular microcirculation, sodium homeostasis, energy and lipid metabolism, and muscle fiber architecture. Much higher levels of acceptance and demand by clinicians can be anticipated for these new techniques in the near future, and radiologists will have to face up to the increasing value of MRI of the skeletal musculature. In this book, recognized experts from around the world provide a comprehensive overview of the value of cutting-edge MRI for the assessment of normal and diseased skeletal muscle. A range of aspects are covered, from the general role of MRI in imaging the skeletal musculature, including in comparison with ultrasonography, through to the current value of MRI in the diagnostic work-up of different diseases. In addition, several chapters present research findings in respect of modern morphological and functional MRI techniques for assessment of the skeletal musculature and provide examples of the added value provided by these techniques when evaluating muscular diseases.

Magnetic resonance imaging of the skeletal musculature

International Nuclear Information System (INIS)

Weber, Marc-Andre

2014-01-01

Comprehensive overview of the value of cutting-edge MRI for the assessment of normal and diseased skeletal muscle. Presents research findings in respect of the role of modern morphological and functional MRI techniques. Provides examples of the added value provided by these techniques when evaluating muscular diseases. Although muscular diseases are a huge and heterogeneous group, in most cases of progressive disease the result is focal or general muscular weakness that presents as an unspecific symptom. Imaging techniques that offer differential diagnostic clues are therefore urgently needed. Despite this, MRI has to date often been assigned a subsidiary role in the diagnostic work-up of these diseases owing to the frequent inability of routine MRI protocols to detect pathognomonic findings. This situation is changing with the advent of modern MRI techniques that offer deeper insights into surrogate pathophysiologic parameters, such as muscular microcirculation, sodium homeostasis, energy and lipid metabolism, and muscle fiber architecture. Much higher levels of acceptance and demand by clinicians can be anticipated for these new techniques in the near future, and radiologists will have to face up to the increasing value of MRI of the skeletal musculature. In this book, recognized experts from around the world provide a comprehensive overview of the value of cutting-edge MRI for the assessment of normal and diseased skeletal muscle. A range of aspects are covered, from the general role of MRI in imaging the skeletal musculature, including in comparison with ultrasonography, through to the current value of MRI in the diagnostic work-up of different diseases. In addition, several chapters present research findings in respect of modern morphological and functional MRI techniques for assessment of the skeletal musculature and provide examples of the added value provided by these techniques when evaluating muscular diseases.

Growth Factors and Tension-Induced Skeletal Muscle Growth

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Vandenburgh, Herman H.

1994-01-01

The project investigated biochemical mechanisms to enhance skeletal muscle growth, and developed a computer based mechanical cell stimulator system. The biochemicals investigated in this study were insulin/(Insulin like Growth Factor) IGF-1 and Steroids. In order to analyze which growth factors are essential for stretch-induced muscle growth in vitro, we developed a defined, serum-free medium in which the differentiated, cultured avian muscle fibers could be maintained for extended periods of time. The defined medium (muscle maintenance medium, MM medium) maintains the nitrogen balance of the myofibers for 3 to 7 days, based on myofiber diameter measurements and myosin heavy chain content. Insulin and IGF-1, but not IGF-2, induced pronounced myofiber hypertrophy when added to this medium. In 5 to 7 days, muscle fiber diameters increase by 71 % to 98% compared to untreated controls. Mechanical stimulation of the avian muscle fibers in MM medium increased the sensitivity of the cells to insulin and IGF-1, based on a leftward shift of the insulin dose/response curve for protein synthesis rates. (54). We developed a ligand binding assay for IGF-1 binding proteins and found that the avian skeletal muscle cultures produced three major species of 31, 36 and 43 kD molecular weight (54) Stretch of the myofibers was found to have no significant effect on the efflux of IGF-1 binding proteins, but addition of exogenous collagen stimulated IGF-1 binding protein production 1.5 to 5 fold. Steroid hormones have a profound effect on muscle protein turnover rates in vivo, with the stress-related glucocorticoids inducing rapid skeletal muscle atrophy while androgenic steroids induce skeletal muscle growth. Exercise in humans and animals reduces the catabolic effects of glucocorticoids and may enhance the anabolic effects of androgenic steroids on skeletal muscle. In our continuing work on the involvement of exogenrus growth factors in stretch-induced avian skeletal muscle growth, we

Ironstone deposits hosted in Eocene carbonates from Bahariya (Egypt)-New perspective on cherty ironstone occurrences

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Afify, A. M.; Sanz-Montero, M. E.; Calvo, J. P.

2015-11-01

This paper gives new insight into the genesis of cherty ironstone deposits. The research was centered on well-exposed, unique cherty ironstone mineralization associated with Eocene carbonates from the northern part of the Bahariya Depression (Egypt). The economically important ironstones occur in the Naqb Formation (Early Eocene), which is mainly formed of shallow marine carbonate deposits. Periods of lowstand sea-level caused extensive early dissolution (karstification) of the depositional carbonates and dolomitization associated with mixing zones of fresh and marine pore-water. In faulted areas, the Eocene carbonate deposits were transformed into cherty ironstone with preservation of the precursor carbonate sedimentary features, i.e. skeletal and non-skeletal grain types, thickness, bedding, lateral and vertical sequential arrangement, and karst profiles. The ore deposits are composed of iron oxyhydroxides, mainly hematite and goethite, chert in the form of micro- to macro-quartz and chalcedony, various manganese minerals, barite, and a number of subordinate sulfate and clay minerals. Detailed petrographic analysis shows that quartz and iron oxides were coetaneous and selectively replaced carbonates, the coarse dolomite crystals having been preferentially transformed into quartz whereas the micro-crystalline carbonates were replaced by the iron oxyhydroxides. A number of petrographic, sedimentological and structural features including the presence of hydrothermal-mediated minerals (e.g., jacobsite), the geochemistry of the ore minerals as well as the structure-controlled location of the mineralization suggest a hydrothermal source for the ore-bearing fluids circulating through major faults and reflect their proximity to centers of magmatism. The proposed formation model can contribute to better understanding of the genetic mechanisms of formation of banded iron formations (BIFs) that were abundant during the Precambrian.

Skeletal muscle digoxin concentration during digitalization and during withdrawal of digoxin treatment.

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Jogestrand, T; Ericsson, F; Sundqvist, K

1981-01-01

Blood samples and skeletal muscle biopsies (m. quadriceps femoris, vastus lateralis) were taken from 15 patients during digitalization or during withdrawal of digoxin treatment for analysis of serum and skeletal muscle digoxin concentrations. A percutaneous needle biopsy technique was used for muscle sampling and digoxin was analysed by radioimmunoassay. During "slow" digitalization with 0.25 mg digoxin daily the skeletal muscle digoxin concentrations after 2 and 4 days were 45% (range 19%--62%; n = 3) and 78% (range 56%--92%; n= 3) respectively, of the steady state concentration (defined as the digoxin concentration after 25--40 days of treatment). After 9 and 11 days of treatment the skeletal muscle digoxin concentrations were 106% (range 84%--133%; n = 5) and 116% (range 72%--164%; n = 3) respectively, of the steady state concentration. A doubling of the digoxin dose gave a proportional increase in skeletal muscle digoxin concentration (three patients). The magnitude of the estimated half-life of skeletal muscle digoxin was the same as previously reportedly in healthy subjects. No significant correlations were found between changes in systolic time intervals and steady state serum or skeletal muscle digoxin concentrations.

Human skeletal muscle digitalis glycoside receptors (Na,K-ATPase)--importance during digitalization.

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Schmidt, T A; Holm-Nielsen, P; Kjeldsen, K

1993-02-01

The aims of the present study were to evaluate in humans the putative importance of skeletal muscle digitalis glycoside receptors (Na,K-ATPase) in the volume of distribution of digoxin and to assess whether therapeutic digoxin exposure might cause digitalis receptor upregulation in skeletal muscle. Samples of the vastus lateralis were obtained postmortem from 11 long-term (9 months to 9 years) digitalized (125-187.5 micrograms daily) and eight undigitalized subjects. In intact samples from digitalized patients, vanadate-facilitated 3H-ouabain binding increased 15% (p 0.30) before and after washing in specific digoxin antibody fragments, respectively. Thus, the present study indicates a approximately 13% occupancy of skeletal muscle digitalis glycoside receptors with digoxin during digitalization. In light of the large skeletal muscle contribution to body mass, this indicates that the skeletal muscle Na,K-ATPase pool constitutes a major volume of distribution for digoxin during digitalization. The results gave no indication of skeletal muscle digitalis glycoside receptor upregulation in response to digoxin treatment. On the contrary, there was evidence of significantly lower (37%, p digitalized patients, which may be of importance for skeletal muscle incapacity in heart failure.

Dissemination of Walker 256 carcinoma cells to rat skeletal muscle

International Nuclear Information System (INIS)

Ueoka, H.; Hayashi, K.; Namba, T.; Grob, D.

1986-01-01

After injection of 10 6 Walker 256 carcinoma cells labelled with 125 I-5-iodo-2'-deoxyuridine into the tail vein, peak concentration in skeletal muscle was 46 cells/g at 60 minutes, which was lower than 169202, 1665, 555, 198 and 133 cells/g, respectively, at 30 or 60 minutes in lung, liver, spleen, kidney and heart. Because skeletal muscle constitutes 37.4% of body weight, the total number of tumor cells was 2323 cells, which was much greater than in spleen, kidney and heart with 238, 271, and 85 cells, respectively, and only less than in lung and liver, at 222857 and 11700 cells, respectively. The total number in skeletal muscle became greater than in liver at 4 hours and than in lung at 24 hours. Ten minutes after injection of 7.5 x 10 6 Walker 256 carcinoma cells into the abdominal aorta of rats, a mean of 31 colony-forming cells were recovered from the gastrocnemius, while 106 cells were recovered from the lung after injection into the tail vein. These results indicate that a large number of viable tumor cells can be arrested in skeletal muscle through circulation. The rare remote metastasis of malignancies into skeletal muscle despite constantly circulating tumor cells does not appear to be due to poor dissemination of tumor cells into muscle but due to unhospitable environment of skeletal muscle

Pneumatized articular eminence in a cohort of orthodontic patients with different sagittal skeletal anomalies. A retrospective cone beam computed tomography study

International Nuclear Information System (INIS)

Miloglu, O.; Celikoglu, M.; Yildirim, E.; Yilmaz, A.B.; Demirtas, O.

2010-01-01

The aim of this study was to determine the prevalence and characteristics of pneumatized articular eminence (PAE) in dental patients using cone beam computed tomography (CBCT) with respect to age, sex, and type of skeletal anomaly. The results were then compared to prevalence studies regarding PAE in the literature. A retrospective study of 603 orthodontic patients aged between 6 and 24 years was performed using sagittal and coronal CBCT images at the Department of Oral and Maxillofacial Radiology (Erzurum, Turkey). The age, gender, skeletal anomaly, and lateral were recorded for all patients, and the types were noted for cases of PAE. The chi-squared test was used for statistical analyses. Sixty-four PAEs were found in 39 orthodontic patients, representing a prevalence of 6.47%. No significant differences in sex (p=0.153), age (before and after puberty, p=0.389), and type of skeletal anomaly were observed (p=0.271). A higher frequency of PAE was detected among dental patients aged 6-24 years when compared to previous studies, most likely because of the use of CBCT images. No significant relation was observed between PAE and the type of skeletal anomalies. One, however, must be aware of these structures to avoid complications in cases for which surgical treatment is planned due to the occlusion and recognize its role in the onset or perpetuation of temporomandibular joint dysfunction. (author)

Muscle Bioenergetic Considerations for Intrinsic Laryngeal Skeletal Muscle Physiology

Science.gov (United States)

Sandage, Mary J.; Smith, Audrey G.

2017-01-01

Purpose: Intrinsic laryngeal skeletal muscle bioenergetics, the means by which muscles produce fuel for muscle metabolism, is an understudied aspect of laryngeal physiology with direct implications for voice habilitation and rehabilitation. The purpose of this review is to describe bioenergetic pathways identified in limb skeletal muscle and…

Content of carbon monoxide in the tissues of rats intoxicated with carbon monoxide in various conditions of acute exposure

Energy Technology Data Exchange (ETDEWEB)

Sokal, J.A.; Majka, J.; Palus, J.

1984-12-01

Tissue carbon monoxide (CO) content was investigated in rats severely intoxicated with CO under various exposure conditions: 1% CO for 4 min, 0.4% CO for 40 min and 0.12% CO for 12 h. Extravascular CO was determined in the heart and skeletal muscles immediately after termination of exposure, and carboxymyoglobin (MbCO) percent saturation was calculated. Total brain CO was estimated immediately after termination of exposure and after the time periods of restitution. After the same exposure conditions, MbCO percent saturation was higher in the heart than in skeletal muscle. In both types of muscle, saturation on myoglobin (Mb) with CO depended on blood carboxyhemoglobin (HbCO) level and not on the duration of exposure. The time course of CO elimination was the same for blood and brain, irrespective of CO exposure conditions. The results obtained showed that acute CO intoxication induced by long duration exposures did not involve CO accumulation in the tissues.

Use of cervical vertebral maturation to determine skeletal age.

Science.gov (United States)

Wong, Ricky W K; Alkhal, Hessa A; Rabie, A Bakr M

2009-10-01

The purpose of this study was to evaluate the validity of the cervical vertebral maturation (CVM) method as an indicator of skeletal age in the circumpubertal period by correlating it to the hand-wrist method (HWM). Hand-wrist and lateral cephalometric radiographs of 400 Chinese subjects were randomly selected. Their ages were 10 to 15 years for girls and 12 to 17 years for boys, so they were within the circumpubertal period. Skeletal ages were assessed according to the CVM method and the HWM. The CVM was significantly correlated with HWM skeletal age (Spearman r = 0.9521 [boys] and 0.9408 [girls]). All patients in cervical vertebral stage 3 of the CVM corresponded to stages MP3-FG or MP3-G (around the peak of the growth spurt) in the HWM. The CVM is a valid indicator of skeletal growth during the circumpubertal period, providing information for timing of growth modification.

Branched-chain amino acid-rich diet improves skeletal muscle wasting caused by cigarette smoke in rats.

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Tomoda, Koichi; Kubo, Kaoru; Hino, Kazuo; Kondoh, Yasunori; Nishii, Yasue; Koyama, Noriko; Yamamoto, Yoshifumi; Yoshikawa, Masanori; Kimura, Hiroshi

2014-04-01

Cigarette smoke induces skeletal muscle wasting by a mechanism not yet fully elucidated. Branched-chain amino acids (BCAA) in the skeletal muscles are useful energy sources during exercise or systemic stresses. We investigated the relationship between skeletal muscle wasting caused by cigarette smoke and changes in BCAA levels in the plasma and skeletal muscles of rats. Furthermore, the effects of BCAA-rich diet on muscle wasting caused by cigarette smoke were also investigated. Wistar Kyoto (WKY) rats that were fed with a control or a BCAA-rich diet were exposed to cigarette smoke for four weeks. After the exposure, the skeletal muscle weight and BCAA levels in plasma and the skeletal muscles were measured. Cigarette smoke significantly decreased the skeletal muscle weight and BCAA levels in both plasma and skeletal muscles, while a BCAA-rich diet increased the skeletal muscle weight and BCAA levels in both plasma and skeletal muscles that had decreased by cigarette smoke exposure. In conclusion, skeletal muscle wasting caused by cigarette smoke was related to the decrease of BCAA levels in the skeletal muscles, while a BCAA-rich diet may improve cases of cigarette smoke-induced skeletal muscle wasting.

Child Skeletal Fluorosis from Indoor Burning of Coal in Southwestern China

International Nuclear Information System (INIS)

Qin, X.; Wang, S.; Yu, M.; Li, X.; Zuo, Z.; Zhang, X.; Wang, L.; Zhang, L.

2010-01-01

Objectives. We assess the prevalence and pathogenic stage of skeletal fluorosis among children and adolescents residing in a severe coal-burning endemic fluorosis area of southwest China. Methods. We used a cross-sectional design. A total of 1,616 students aged between 7 and 16 years in Zhijin County, Guizhou, China in late 2004 were selected via a cluster sampling of all 9-year compulsory education schools to complete the study questionnaire. Any student lived in a household that burned coal, used an open-burning stove, or baked foodstuffs over a coal stove was deemed high-risk for skeletal fluorosis. About 23% (370) of students (188 boys, 182 girls) were identified as high-risk and further examined by X-ray. Results. One-third of the 370 high-risk participants were diagnosed with skeletal fluorosis. Overall prevalence of child skeletal fluorosis due to indoor burning of coal was 7.5%. Children aged 12 16 years were significantly more likely to be diagnosed with skeletal fluorosis than children aged 7 11 years (OR = 1.84, 95% CI: 1.17 2.90; P = .0082). Four types of skeletal fluorosis were identified: constrictive (60.7%), raritas (15.6%), mixed (16.4%), and soft (7.4%). Most diagnosed cases (91%) were mild or moderate in severity. In addition, about 97% of 370 high-risk children were identified with dental fluorosis. Dental fluorosis was highly correlated with skeletal fluorosis in this study. Conclusions. Skeletal fluorosis among children may contribute to poor health and reduced productivity when they reach adulthood. Further efforts to reduce fluoride exposure among children in southwestern of China where coal is burned indoors are desperately needed.

Effect of experimental hyperthyroidism on protein turnover in skeletal and cardiac muscle.

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Carter, W J; Van Der Weijden Benjamin, W S; Faas, F H

1980-10-01

Since experimental hyperthyroidism reduces skeletal muscle mass while simultaneously increasing cardiac muscle mass, the effect of hyperthyroidism on muscle protein degradation was compared in skeletal and cardiac muscle. Pulse-labeling studies using (3H) leucine and (14C) carboxyl labeled aspartate and glutamate were carried out. Hyperthyroidism caused a 25%-29% increase in protein breakdown in both sarcoplasmic and myofibrillar fractions of skeletal muscle. Increased muscle protein degradation may be a major factor in the development of skeletal muscle wasting and weakness in hyperthyroidism. In contrast, protein breakdown appeared to be reduced 22% in the sarcoplasmic fraction of hyperthyroid heart muscle and was unchanged in the myofibrillar fraction. Possible reasons for the contrasting effects of hyperthyroidism on skeletal and cardiac muscle include increased sensitivity of the hyperthyroid heart to catecholamines, increased cardiac work caused by the hemodynamic effects of hyperthyroidism, and a different direct effect of thyroid hormone at the nuclear level in cardiac as opposed to skeletal muscle.

Generation of skeletal muscle from transplanted embryonic stem cells in dystrophic mice

International Nuclear Information System (INIS)

Bhagavati, Satyakam; Xu Weimin

2005-01-01

Embryonic stem (ES) cells have great therapeutic potential because of their capacity to proliferate extensively and to form any fully differentiated cell of the body, including skeletal muscle cells. Successful generation of skeletal muscle in vivo, however, requires selective induction of the skeletal muscle lineage in cultures of ES cells and following transplantation, integration of appropriately differentiated skeletal muscle cells with recipient muscle. Duchenne muscular dystrophy (DMD), a severe progressive muscle wasting disease due to a mutation in the dystrophin gene and the mdx mouse, an animal model for DMD, are characterized by the absence of the muscle membrane associated protein, dystrophin. Here, we show that co-culturing mouse ES cells with a preparation from mouse muscle enriched for myogenic stem and precursor cells, followed by injection into mdx mice, results occasionally in the formation of normal, vascularized skeletal muscle derived from the transplanted ES cells. Study of this phenomenon should provide valuable insights into skeletal muscle development in vivo from transplanted ES cells

Slope and basinal deposits adjacent to isolated carbonate platforms in the Indian Ocean: Sedimentology, geomorphology, and a new 1.2 Ma record of highstand shedding

Science.gov (United States)

Counts, J. W.; Jorry, S.; Jouet, G.

2017-12-01

Newly analyzed bathymetric, seismic, and core data from carbonate-topped seamounts in the Mozambique Channel reveals a variety of depositional processes and products operating on platform slopes and adjacent basins. Mass transport complexes (including turbidites and debrites), leveed channel systems with basin-floor fans, and contourites are imaged in high resolution in both seafloor maps and cross-section, and show both differences and similarities compared with platform slopes in the Bahamas and elsewhere. In some, though not all, platforms, increased sedimentation can be observed on the leeward margins, and slope rugosity may be asymmetric with respect to prevailing wind direction. Deposition is also controlled by glacial-interglacial cycles; cores taken from the lower slopes (3000+ m water depth) of carbonate platforms reveal a causative relationship between sea level and aragonite export to the deep ocean. δ18O isotopes from planktonic and benthic foraminifera of two 27-meter cores, reveal a high-resolution, continuous depositional record of carbonate sediment dating back to 1.2 Ma. Sea level rise, as determined by correlation with the LR04 benthic stack, is coincident with increased aragonite flux from platform tops. Gravity flow deposits are also affected by platform flooding—the frequency of turbidite/debrite deposits on pinnacle slopes increases during highstand, although such deposits are also present during glacial episodes. The results reported here are the first record of highstand shedding in the southern Indian Ocean, and provide the longest Quaternary sediment record to date in the region, including the Mid-Brunhes transition (MIS 11) that serves as an analog for the current climate conditions. In addition, this is the first study to describe sedimentation on the slopes of these platforms, providing an important point of comparison that has the potential to influence source-to-sink carbonate facies models.

Sedimentary Record of the Back-Arc Basins of South-Central Mexico: an Evolution from Extensional Basin to Carbonate Platform.

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Sierra-Rojas, M. I.; Molina-Garza, R. S.; Lawton, T. F.

2015-12-01

The Lower Cretaceous depositional systems of southwestern Oaxaquia, in south-central Mexico, were controlled by tectonic processes related to the instauration of a continental arc and the accretion of the Guerrero arc to mainland Mexico. The Atzompa Formation refers to a succession of conglomerate, sandstone, siltstone, and limestone that crop out in southwestern Mexico with Early Cretaceous fauna and detrital zircon maximum depositional ages. The sedimentary record shows a transition from early fluvial/alluvial to shallow marine depositional environments. The first stage corresponds to juvenile fluvial/alluvial setting followed by a deep lacustrine depositional environment, suggesting the early stages of an extensional basin. The second stage is characterized by anabranched deposits of axial fluvial systems flowing to the NE-SE, showing deposition during a period of rapid subsidence. The third and final stage is made of tidal deposits followed, in turn, by abrupt marine flooding of the basin and development of a Barremian-Aptian carbonate ramp. We interpret the Tentzo basin as a response to crustal extension in a back-arc setting, with high rates of sedimentation in the early stages of the basin (3-4 mm/m.y), slower rates during the development of starved fluvial to tidal systems and carbonate ramps, and at the top of the Atzompa Formation an abrupt deepening of the basin due to flexural subsidence related to terrane docking and attendant thrusting to the west. These events were recorded in the back-arc region of a continental convergent margin (Zicapa arc) where syn-sedimentary magmatism is indicated by Early Cretaceous detrital and volcanic clasts from alluvial fan facies west of the basin. Finally, and as a response to the accretion of the Guerrero superterrane to Oaxaquia during the Aptian, a carbonate platform facing toward the Gulf of Mexico was established in central to eastern Oaxaquia.

Late Neogene benthic stable isotope record of ODP Site 999: Implications for Caribbean paleoceanography, organic carbon burial and the Messininian salinity crisis

Science.gov (United States)

Bickert, T.; Haug, G.; Tiedemann, R.

2003-04-01

The late Neogene closure of the seaway between the North and South American continents is thought to have caused extensive changes in ocean circulation and Northern Hemisphere climate. The timing and consequences of the emergence of the Isthmus of Panama for the ocean circulation have been addressed in several papers which indicate a marked reorganization of surface and deep ocean circulation starting 4.6 million years ago. However, the biogeographic development of marine faunas and floras on both sides of the Panama Isthmus suggests that the paleoceanographic changes related to the closing of the isthmus started much earlier. Furthermore, the closing history of the Panama Seaway overlaps with the tectonic evolution of other ocean gateways in the late Miocene, especially the closure of the Strait of Gibraltar, which led to a transient isolation of the Mediterranean Sea from the Atlantic Ocean, known as the Messinian Salinity Crisis. We report on epibenthic foraminiferal d18O and d13C and percentage sand records of the carbonate fraction from Caribbean ODP Site 999 (12°44´N, 78° 44´W, water depth 2828 m) spanning the interval from 8.6 to 5.3 Ma. Low epibenthic d13C values and low sand contents indicate a poorly ventilated deep Caribbean throughout the late Miocene. At this time the deep Caribbean was dominated by a nutrient-rich Southern Ocean water mass. A mostly constant d13C gradient between the Caribbean and deep Atlantic records suggests that the fluctuations in d13C reflect rather global changes in d13C of the dissolved inorganic carbon due to varying erosion of organic carbon from terrigenous soils and shelf sediments. The observed 100-ky cyclicity of epibenthic d13C is in well accordance with the variability of the terrigenous input to the equatorial Atlantic as recorded by susceptibility records of the Ceara Rise. However, some gradient changes between 6.8 and 5.6 Ma indicate a poorer ventilation of the deep Atlantic related to a reduced production of

Double-read of skeletal surveys in suspected non-accidental trauma: what we learned

Energy Technology Data Exchange (ETDEWEB)

Karmazyn, Boaz; Wanner, Matthew R.; Marine, Megan B. [Indiana University School of Medicine, Department of Radiology and Imaging Sciences, Riley Hospital for Children, Indianapolis, IN (United States); Miller, Elise M.; Jennings, S.G. [Indiana University School of Medicine, Department of Radiology and Imaging Sciences, Indianapolis, IN (United States); Lay, Sara E. [Indiana University School of Medicine, Methodist Hospital, Department of Radiology and Imaging Sciences, Indianapolis, IN (United States); Massey, James M. [The Children' s Hospital at TriStar Centennial, Department of Imaging, Nashville, TN (United States); Ouyang, Fangqian [Indiana University School of Medicine, Department of Biostatistics, Indianapolis, IN (United States); Hibbard, Roberta A. [Indiana University School of Medicine, Department of Pediatrics, Section of Child Protection Programs, Riley Hospital for Children, Indianapolis, IN (United States)

2017-05-15

Missing a fracture in a child on skeletal surveys for suspected non-accidental trauma can have devastating results. Double-read has the potential to improve fracture detection. However the yield of double-read is unknown. To determine the advantage of double-read versus single-read of radiographic skeletal surveys for suspected non-accidental trauma. The study was performed in two phases. In the first phase (April 2013 to September 2013), double-read was performed for all skeletal surveys obtained during weekday working hours. Because we had no new double-read findings in studies initially read as negative, we conducted a second phase (January 2014 to March 2014). In the second phase we limited double-reads to skeletal surveys found positive on the first read. At the end of this period, we retrospectively performed double-read for all initially negative skeletal surveys. We excluded follow-up skeletal surveys. The difference in discrepancy (new fracture or false diagnosis of a fracture) ratio between negative and positive skeletal surveys was evaluated using the Fisher exact test, and change in discrepancy ratio between the first and second study phases was evaluated using the stratified Cochran-Mantel-Haenszel test. Overall in the two phases, 178 skeletal surveys were performed in 178 children (67 girls) with mean age of 9 months (range 3 days to 3.7 years). Double-read found 16 discrepancies in 8/178 (4.5%) skeletal surveys. Seven of these studies showed additional fractures (n=15). In one study, an initial read of a skull fracture was read as a variant on the second read. There was a significant (P=0.01) difference between rate of disagreement in negative skeletal surveys (1/104, 1.0%) and positive skeletal surveys (7/74, 9.5%). No significant change in disagreement rate was demonstrated between the two phases of the study (P=0.59). Double-read of skeletal survey for suspected non-accidental trauma found false-negative fractures in a few cases and rarely found

Double-read of skeletal surveys in suspected non-accidental trauma: what we learned

International Nuclear Information System (INIS)

Karmazyn, Boaz; Wanner, Matthew R.; Marine, Megan B.; Miller, Elise M.; Jennings, S.G.; Lay, Sara E.; Massey, James M.; Ouyang, Fangqian; Hibbard, Roberta A.

2017-01-01

Missing a fracture in a child on skeletal surveys for suspected non-accidental trauma can have devastating results. Double-read has the potential to improve fracture detection. However the yield of double-read is unknown. To determine the advantage of double-read versus single-read of radiographic skeletal surveys for suspected non-accidental trauma. The study was performed in two phases. In the first phase (April 2013 to September 2013), double-read was performed for all skeletal surveys obtained during weekday working hours. Because we had no new double-read findings in studies initially read as negative, we conducted a second phase (January 2014 to March 2014). In the second phase we limited double-reads to skeletal surveys found positive on the first read. At the end of this period, we retrospectively performed double-read for all initially negative skeletal surveys. We excluded follow-up skeletal surveys. The difference in discrepancy (new fracture or false diagnosis of a fracture) ratio between negative and positive skeletal surveys was evaluated using the Fisher exact test, and change in discrepancy ratio between the first and second study phases was evaluated using the stratified Cochran-Mantel-Haenszel test. Overall in the two phases, 178 skeletal surveys were performed in 178 children (67 girls) with mean age of 9 months (range 3 days to 3.7 years). Double-read found 16 discrepancies in 8/178 (4.5%) skeletal surveys. Seven of these studies showed additional fractures (n=15). In one study, an initial read of a skull fracture was read as a variant on the second read. There was a significant (P=0.01) difference between rate of disagreement in negative skeletal surveys (1/104, 1.0%) and positive skeletal surveys (7/74, 9.5%). No significant change in disagreement rate was demonstrated between the two phases of the study (P=0.59). Double-read of skeletal survey for suspected non-accidental trauma found false-negative fractures in a few cases and rarely found

Current opportunities and challenges in skeletal muscle tissue engineering

NARCIS (Netherlands)

Koning, Merel; Harmsen, Martin C; van Luyn, Marja J A; Werker, Paul M N

The purpose of this article is to give a concise review of the current state of the art in tissue engineering (TE) of skeletal muscle and the opportunities and challenges for future clinical applicability. The endogenous progenitor cells of skeletal muscle, i.e. satellite cells, show a high

ALDH2 restores exhaustive exercise-induced mitochondrial dysfunction in skeletal muscle

International Nuclear Information System (INIS)

Zhang, Qiuping; Zheng, Jianheng; Qiu, Jun; Wu, Xiahong; Xu, Yangshuo; Shen, Weili; Sun, Mengwei

2017-01-01

Background: Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is highly expressed in heart and skeletal muscles, and is the major enzyme that metabolizes acetaldehyde and toxic aldehydes. The cardioprotective effects of ALDH2 during cardiac ischemia/reperfusion injury have been recognized. However, less is known about the function of ALDH2 in skeletal muscle. This study was designed to evaluate the effect of ALDH2 on exhaustive exercise-induced skeletal muscle injury. Methods: We created transgenic mice expressing ALDH2 in skeletal muscles. Male wild-type C57/BL6 (WT) and ALDH2 transgenic mice (ALDH2-Tg), 8-weeks old, were challenged with exhaustive exercise for 1 week to induce skeletal muscle injury. Animals were sacrificed 24 h post-exercise and muscle tissue was excised. Results: ALDH2-Tg mice displayed significantly increased treadmill exercise capacity compared to WT mice. Exhaustive exercise caused an increase in mRNA levels of the muscle atrophy markers, Atrogin-1 and MuRF1, and reduced mitochondrial biogenesis and fusion in WT skeletal muscles; these effects were attenuated in ALDH2-Tg mice. Exhaustive exercise also enhanced mitochondrial autophagy pathway activity, including increased conversion of LC3-I to LC3-II and greater expression of Beclin1 and Bnip3; the effects of which were mitigated by ALDH2 overexpression. In addition, ALDH2-Tg reversed the increase of an oxidative stress biomarker (4-hydroxynonenal) and decreased levels of mitochondrial antioxidant proteins, including manganese superoxide dismutase and NAD(P)H:quinone oxidoreductase 1, in skeletal muscle induced by exhaustive exercise. Conclusion: ALDH2 may reverse skeletal muscle mitochondrial dysfunction due to exhaustive exercise by regulating mitochondria dynamic remodeling and enhancing the quality of mitochondria. - Highlights: • Skeletal muscle ALDH2 expression and activity declines during exhaustive exercise. • ALDH2 overexpression enhances physical performance and restores muscle

Water and carbon stable isotope records from natural archives: a new database and interactive online platform for data browsing, visualizing and downloading

Science.gov (United States)

Bolliet, Timothé; Brockmann, Patrick; Masson-Delmotte, Valérie; Bassinot, Franck; Daux, Valérie; Genty, Dominique; Landais, Amaelle; Lavrieux, Marlène; Michel, Elisabeth; Ortega, Pablo; Risi, Camille; Roche, Didier M.; Vimeux, Françoise; Waelbroeck, Claire

2016-08-01

Past climate is an important benchmark to assess the ability of climate models to simulate key processes and feedbacks. Numerous proxy records exist for stable isotopes of water and/or carbon, which are also implemented inside the components of a growing number of Earth system model. Model-data comparisons can help to constrain the uncertainties associated with transfer functions. This motivates the need of producing a comprehensive compilation of different proxy sources. We have put together a global database of proxy records of oxygen (δ18O), hydrogen (δD) and carbon (δ13C) stable isotopes from different archives: ocean and lake sediments, corals, ice cores, speleothems and tree-ring cellulose. Source records were obtained from the georeferenced open access PANGAEA and NOAA libraries, complemented by additional data obtained from a literature survey. About 3000 source records were screened for chronological information and temporal resolution of proxy records. Altogether, this database consists of hundreds of dated δ18O, δ13C and δD records in a standardized simple text format, complemented with a metadata Excel catalog. A quality control flag was implemented to describe age markers and inform on chronological uncertainty. This compilation effort highlights the need to homogenize and structure the format of datasets and chronological information as well as enhance the distribution of published datasets that are currently highly fragmented and scattered. We also provide an online portal based on the records included in this database with an intuitive and interactive platform (http://climateproxiesfinder.ipsl.fr/), allowing one to easily select, visualize and download subsets of the homogeneously formatted records that constitute this database, following a choice of search criteria, and to upload new datasets. In the last part, we illustrate the type of application allowed by our database by comparing several key periods highly investigated by the

Skeletal anteroposterior discrepancy and vertical type effects on lower incisor preoperative decompensation and postoperative compensation in skeletal Class III patients.

Science.gov (United States)

Ahn, Hyo-Won; Baek, Seung-Hak

2011-01-01

To determine the initial compensation, preoperative decompensation, and postoperative compensation of the lower incisors according to the skeletal anteroposterior discrepancy and vertical type in skeletal Class III patients. The samples consisted of 68 skeletal Class III patients treated with two-jaw surgery and orthodontic treatment. Lateral cephalograms were taken before preoperative orthodontic treatment (T0) and before surgery (T1) and after debonding (T2). According to skeletal anteroposterior discrepancy/vertical type (ANB, criteria  =  -4°; SN-GoMe, criteria  =  35°) at the T0 stage, the samples were allocated into group 1 (severe anteroposterior discrepancy/hypodivergent vertical type, N  =  17), group 2 (moderate anteroposterior discrepancy/hypodivergent vertical type, N  =  17), group 3 (severe anteroposterior discrepancy/hyperdivergent vertical type, N  =  17), or group 4 (moderate anteroposterior discrepancy/hyperdivergent vertical type, N  =  17). After measurement of variables, one-way analysis of variance with Duncan's multiple comparison test, crosstab analysis, and Pearson correlation analysis were performed. At T0, groups 3 and 2 exhibited the most and least compensated lower incisors. In group 2, good preoperative decompensation and considerable postoperative compensation resulted in different values for T0, T1, and T2 (IMPA, T0 lower incisors in Class III patients.

Sedimentary record of water column trophic conditions and sediment carbon fluxes in a tropical water reservoir (Valle de Bravo, Mexico).

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Carnero-Bravo, Vladislav; Merino-Ibarra, Martín; Ruiz-Fernández, Ana Carolina; Sanchez-Cabeza, Joan Albert; Ghaleb, Bassam

2015-03-01

Valle de Bravo (VB) is the main water reservoir of the Cutzamala hydraulic system, which provides 40% of the drinking water consumed in the Mexico City Metropolitan Area and exhibits symptoms of eutrophication. Nutrient (C, N and P) concentrations were determined in two sediment cores to reconstruct the water column trophic evolution of the reservoir and C fluxes since its creation in 1947. Radiometric methods ((210)Pb and (137)Cs) were used to obtain sediment chronologies, using the presence of pre-reservoir soil layers in one of the cores as an independent chronological marker. Mass accumulation rates ranged from 0.12 to 0.56 g cm(-2) year(-1) and total organic carbon (TOC) fluxes from 122 to 380 g m(-2) year(-1). Total N ranged 4.9-48 g m(-2) year(-1), and total P 0.6-4.2 g m(-2) year(-1). The sedimentary record shows that all three (C, N and P) fluxes increased significantly after 1991, in good agreement with the assessed trophic evolution of VB and with historic and recent real-time measurements. In the recent years (1992-2006), the TOC flux to the bottom of VB (average 250 g m(-2) year(-1), peaks 323 g m(-2) year(-1)) is similar to that found in highly eutrophic reservoirs and impoundments. Over 1/3 of the total C burial since dam construction, circa 70,000 t, has occurred in this recent period. These results highlight the usefulness of the reconstruction of carbon and nutrient fluxes from the sedimentary record to assess carbon burial and its temporal evolution in freshwater ecosystems.

Satellite cells in human skeletal muscle plasticity

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Tim eSnijders

2015-10-01

Full Text Available Skeletal muscle satellite cells are considered to play a crucial role in muscle fiber maintenance, repair and remodelling. Our knowledge of the role of satellite cells in muscle fiber adaptation has traditionally relied on in vitro cell and in vivo animal models. Over the past decade, a genuine effort has been made to translate these results to humans under physiological conditions. Findings from in vivo human studies suggest that satellite cells play a key role in skeletal muscle fiber repair/remodelling in response to exercise. Mounting evidence indicates that aging has a profound impact on the regulation of satellite cells in human skeletal muscle. Yet, the precise role of satellite cells in the development of muscle fiber atrophy with age remains unresolved. This review seeks to integrate recent results from in vivo human studies on satellite cell function in muscle fiber repair/remodelling in the wider context of satellite cell biology whose literature is largely based on animal and cell models.

Satellite cells in human skeletal muscle plasticity.

Science.gov (United States)

Snijders, Tim; Nederveen, Joshua P; McKay, Bryon R; Joanisse, Sophie; Verdijk, Lex B; van Loon, Luc J C; Parise, Gianni

2015-01-01

Skeletal muscle satellite cells are considered to play a crucial role in muscle fiber maintenance, repair and remodeling. Our knowledge of the role of satellite cells in muscle fiber adaptation has traditionally relied on in vitro cell and in vivo animal models. Over the past decade, a genuine effort has been made to translate these results to humans under physiological conditions. Findings from in vivo human studies suggest that satellite cells play a key role in skeletal muscle fiber repair/remodeling in response to exercise. Mounting evidence indicates that aging has a profound impact on the regulation of satellite cells in human skeletal muscle. Yet, the precise role of satellite cells in the development of muscle fiber atrophy with age remains unresolved. This review seeks to integrate recent results from in vivo human studies on satellite cell function in muscle fiber repair/remodeling in the wider context of satellite cell biology whose literature is largely based on animal and cell models.

The magnesium isotope record of cave carbonate archives

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S. Riechelmann

2012-11-01

Full Text Available Here we explore the potential of magnesium (δ²⁶Mg isotope time-series data as continental climate proxies in speleothem calcite archives. For this purpose, a total of six Pleistocene and Holocene stalagmites from caves in Germany, Morocco and Peru and two flowstones from a cave in Austria were investigated. These caves represent the semi-arid to arid (Morocco, the warm-temperate (Germany, the equatorial-humid (Peru and the cold-humid (Austria climate zones. Changes in the calcite magnesium isotope signature with time are compared against carbon and oxygen isotope records from these speleothems. Similar to other proxies, the non-trivial interaction of a number of environmental, equilibrium and disequilibrium processes governs the δ²⁶Mg fractionation in continental settings. These include the different sources of magnesium isotopes such as rainwater or snow as well as soil and host rock, soil zone biogenic activity, shifts in silicate versus carbonate weathering ratios and residence time of water in the soil and karst zone. Pleistocene stalagmites from Morocco show the lowest mean δ²⁶Mg values (GDA: −4.26 ± 0.07‰ and HK3: −4.17 ± 0.15‰, and the data are well explained in terms of changes in aridity over time. The Pleistocene to Holocene stalagmites from Peru show the highest mean value of all stalagmites (NC-A and NC-B δ²⁶Mg: −3.96 ± 0.04‰ but only minor variations in Mg-isotope composition, which is consistent with the rather stable equatorial climate at this site. Holocene stalagmites from Germany (AH-1 mean δ²⁶Mg: −4.01 ± 0.07‰; BU 4 mean δ²⁶Mg: −4.20 ± 0.10‰ suggest changes in outside air temperature was the principal driver rather than rainfall amount. The alpine Pleistocene flowstones from Austria (SPA 52: −3.00 ± 0.73‰; SPA 59: −3.70 ± 0.43‰ are affected by glacial versus interglacial climate change with outside air temperature

Calcification rate and the stable carbon, oxygen, and nitrogen isotopes in the skeleton, host tissue, and zooxanthellae of bleached and recovering Hawaiian corals

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Rodrigues, Lisa J.; Grottoli, Andréa G.

2006-06-01

We tested the effectiveness of stable isotopes as recorders of physiological changes that occur during coral bleaching and recovery. Montipora capitata and Porites compressa fragments were bleached in outdoor tanks with seawater temperature raised to 30 °C (treatment corals) for one month. Additional fragments were maintained at 27 °C in separate tanks (control corals). After one month, (0 months recovery), buoyant weight was measured and a subset of fragments was frozen. Remaining fragments were returned to the reef for recovery. After 1.5, 4, and 8 months, fragments were collected, measured for buoyant weight, and frozen. Fragments were analyzed for stable carbon and oxygen isotopic compositions of the skeleton (δ 13C s; δ 18O s) and nitrogen and carbon isotopic compositions of the host tissue (δ 15N h; δ 13C h) and zooxanthellae (δ 15N z; δ 13C z). δ 13C s decreased immediately after bleaching in M. capitata, but not in P. compressa. δ 18O s of both species failed to record the warming event. During the remaining months of recovery, δ 13C s and δ 18O s were more enriched in treatment than control corals due to decreases in calcification and metabolic fractionation during that time. Increased δ 15N h of treatment P. compressa may be due to expelled zooxanthellae during bleaching and recovery. Increased δ 15N z at 1.5 months in treatment fragments of both species reflects the increased incorporation of dissolved inorganic nitrogen to facilitate mitotic cell division and/or chl a/cell recovery. Changes in δ 13C h and δ 13C z at 1.5 months in treatment M. capitata indicated a large increase in heterotrophically acquired carbon relative to photosynthetically fixed carbon. We experimentally show that isotopes in coral skeleton, host tissue and zooxanthellae can be used to verify physiological changes during bleaching and recovery, but their use as a proxy for past bleaching events in the skeletal record is limited.

Skeletal myogenic differentiation of human urine-derived cells as a potential source for skeletal muscle regeneration.

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Chen, Wei; Xie, Minkai; Yang, Bin; Bharadwaj, Shantaram; Song, Lujie; Liu, Guihua; Yi, Shanhong; Ye, Gang; Atala, Anthony; Zhang, Yuanyuan

2017-02-01

Stem cells are regarded as possible cell therapy candidates for skeletal muscle regeneration. However, invasive harvesting of those cells can cause potential harvest-site morbidity. The goal of this study was to assess whether human urine-derived stem cells (USCs), obtained through non-invasive procedures, can differentiate into skeletal muscle linage cells (Sk-MCs) and potentially be used for skeletal muscle regeneration. In this study, USCs were harvested from six healthy individuals aged 25-55. Expression profiles of cell-surface markers were assessed by flow cytometry. To optimize the myogenic differentiation medium, we selected two from four different types of myogenic differentiation media to induce the USCs. Differentiated USCs were identified with myogenic markers by gene and protein expression. USCs were implanted into the tibialis anterior muscles of nude mice for 1 month. The results showed that USCs displayed surface markers with positive staining for CD24, CD29, CD44, CD73, CD90, CD105, CD117, CD133, CD146, SSEA-4 and STRO-1, and negative staining for CD14, CD31, CD34 and CD45. After myogenic differentiation, a change in morphology was observed from 'rice-grain'-like cells to spindle-shaped cells. The USCs expressed specific Sk-MC transcripts and protein markers (myf5, myoD, myosin, and desmin) after being induced with different myogenic culture media. Implanted cells expressed Sk-MC markers stably in vivo. Our findings suggest that USCs are able to differentiate into the Sk-MC lineage in vitro and after being implanted in vivo. Thus, they might be a potential source for cell injection therapy in the use of skeletal muscle regeneration. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

Development of severe skeletal defects in induced SHP-2-deficient adult mice: a model of skeletal malformation in humans with SHP-2 mutations

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Timothy J. Bauler

2011-03-01

SHP-2 (encoded by PTPN11 is a ubiquitously expressed protein tyrosine phosphatase required for signal transduction by multiple different cell surface receptors. Humans with germline SHP-2 mutations develop Noonan syndrome or LEOPARD syndrome, which are characterized by cardiovascular, neurological and skeletal abnormalities. To study how SHP-2 regulates tissue homeostasis in normal adults, we used a conditional SHP-2 mouse mutant in which loss of expression of SHP-2 was induced in multiple tissues in response to drug administration. Induced deletion of SHP-2 resulted in impaired hematopoiesis, weight loss and lethality. Most strikingly, induced SHP-2-deficient mice developed severe skeletal abnormalities, including kyphoses and scolioses of the spine. Skeletal malformations were associated with alterations in cartilage and a marked increase in trabecular bone mass. Osteoclasts were essentially absent from the bones of SHP-2-deficient mice, thus accounting for the osteopetrotic phenotype. Studies in vitro revealed that osteoclastogenesis that was stimulated by macrophage colony-stimulating factor (M-CSF and receptor activator of nuclear factor kappa B ligand (RANKL was defective in SHP-2-deficient mice. At least in part, this was explained by a requirement for SHP-2 in M-CSF-induced activation of the pro-survival protein kinase AKT in hematopoietic precursor cells. These findings illustrate an essential role for SHP-2 in skeletal growth and remodeling in adults, and reveal some of the cellular and molecular mechanisms involved. The model is predicted to be of further use in understanding how SHP-2 regulates skeletal morphogenesis, which could lead to the development of novel therapies for the treatment of skeletal malformations in human patients with SHP-2 mutations.

Skeletal muscle inflammation and insulin resistance in obesity

Science.gov (United States)

Wu, Huaizhu; Ballantyne, Christie M.

2017-01-01

Obesity is associated with chronic inflammation, which contributes to insulin resistance and type 2 diabetes mellitus. Under normal conditions, skeletal muscle is responsible for the majority of insulin-stimulated whole-body glucose disposal; thus, dysregulation of skeletal muscle metabolism can strongly influence whole-body glucose homeostasis and insulin sensitivity. Increasing evidence suggests that inflammation occurs in skeletal muscle in obesity and is mainly manifested by increased immune cell infiltration and proinflammatory activation in intermyocellular and perimuscular adipose tissue. By secreting proinflammatory molecules, immune cells may induce myocyte inflammation, adversely regulate myocyte metabolism, and contribute to insulin resistance via paracrine effects. Increased influx of fatty acids and inflammatory molecules from other tissues, particularly visceral adipose tissue, can also induce muscle inflammation and negatively regulate myocyte metabolism, leading to insulin resistance. PMID:28045398

Skeletal muscle as a gene regulatory endocrine organ

DEFF Research Database (Denmark)

Karstoft, Kristian; Pedersen, Bente K.

2016-01-01

Purpose of review Skeletal muscle is gaining increased attention as an endocrine organ. Recently, novel myokines and new effects of already established myokines have been identified. The objective of this review is to give an update on the recent advances in the field. Recent findings Several...... hundred putative myokines have been described, some of which are induced by contraction and differentially regulated between healthy and metabolically diseased individuals. Interleukin-6 (IL-6) is the prototype myokine, which was identified as a muscle-derived cytokine 15 years ago. Recently, IL-6 has...... on training status. IL-15 has been established as a cytokine mediating cross-talk between skeletal muscle and skin tissue, and decorin has been characterized as a contraction-induced myokine which apparently is differentially regulated between healthy and dysglycemic individuals. Summary Skeletal muscle...

A study of skeletal metastasis of carcinoma of the uterine cervix

International Nuclear Information System (INIS)

Tanouchi, Miki; Sui, Osamu; Kashihara, Kenichi

1990-01-01

Between January 1980 and December 1988, 373 patients with carcinoma of the uterine cervix were treated at the Department of Radiology, Tokushima University Hospital. Of the 373 patients, 229 were treated by radiotherapy alone, and 144 were treated by post-operative radiotherapy. The incidence of skeletal metastasis was 6.4%, 24 patients out of 373. Ten of these patients were treated with radiotherapy alone, and 14 with radical surgery and radiotherapy. Nineteen patients belonged in the early clinical stage (stage Ia through stage IIb). Lesions of skeletal metastases were usually detected within 2 years after the initial treatment, and the most common site of skeletal metastasis was the pelvic bone, followed by the lumbar spine. Most patients with skeletal metastases were treated by radiotherapy, chemotherapy, and combined radio- and chemotherapy. Severe pain due to skeletal metastasis was relieved by radiotherapy and combined therapy, but no method of treatment could extend the prognosis. (author)

Molar height and dentoalveolar compensation in adult subjects with skeletal open bite.

Science.gov (United States)

Kucera, Josef; Marek, Ivo; Tycova, Hana; Baccetti, Tiziano

2011-07-01

To evaluate the skeletal and dentoalveolar components in adult subjects with skeletal open bite in the presence or absence of dental compensation. The study sample included 69 adult female subjects who belonged to three groups according to skeletal vertical relationships and overbite. A total of 15 variables (5 angular, 10 linear) were evaluated. Values in the dentally compensated open bite group (COBG), the dentally noncompensated open bite group (NCOBG), and the control group with normal vertical skeletal relationships and overbite (CG) were compared by means of parametric statistics. The COBG and the NCOBG showed significantly greater incisor and molar heights in both jaws than the CG. No significant difference in upper or lower molar height was found between COBG and NCOBG. Incisor height was significantly greater in COBG than in NCOBG. Elongation in the incisor region was accompanied by significant narrowing of the lower anterior alveolar process in both skeletal open bite groups. Proclination of the upper incisors was significantly smaller in the COBG than in the other groups. Dentoalveolar components consisting of incisor elongation and inclination play a significant role in compensating for skeletal open bite configuration in adult subjects. Increased molar height is a common finding in adults with skeletal open bite.

Relative Skeletal Maturation and Population Ancestry in Nonobese Children and Adolescents.

Science.gov (United States)

McCormack, Shana E; Chesi, Alessandra; Mitchell, Jonathan A; Roy, Sani M; Cousminer, Diana L; Kalkwarf, Heidi J; Lappe, Joan M; Gilsanz, Vicente; Oberfield, Sharon E; Shepherd, John A; Mahboubi, Soroosh; Winer, Karen K; Kelly, Andrea; Grant, Struan Fa; Zemel, Babette S

2017-01-01

More rapid skeletal maturation in African-American (AA) children is recognized and generally attributed to an increased prevalence of obesity. The objective of the present study was to evaluate the effects of population ancestry on relative skeletal maturation in healthy, non-obese children and adolescents, accounting for body composition and sexual maturation. To do this, we leveraged a multiethnic, mixed-longitudinal study with annual assessments for up to 7 years (The Bone Mineral Density in Childhood Study and its ancillary cohort) conducted at five US clinical centers. Participants included 1592 children, skeletally immature (45% females, 19% AA) who were aged 5 to 17 years at study entry. The primary outcome measure was relative skeletal maturation as assessed by hand-wrist radiograph. Additional covariates measured included anthropometrics, body composition by dual-energy X-ray absorptiometry (DXA), and Tanner stage of sexual maturation. Using mixed effects longitudinal models, without covariates, advancement in relative skeletal maturation was noted in self-reported AA girls (∼0.33 years, p ancestry groups showed independent positive associations of height, lean mass, fat mass, and puberty with relative skeletal maturation. The effect of ancestry was attenuated but persistent after accounting for covariates: for girls, 0.19 years (ancestry by self-report, p = 0.02) or 0.29 years (ancestry by admixture, p = 0.004); and for boys, 0.20 years (ancestry by self-report, p = 0.004), or 0.29 years (ancestry by admixture, p = 0.004). In summary, we conclude that advancement in relative skeletal maturation was associated with AA ancestry in healthy, non-obese children, independent of growth, body composition, and puberty. Further research into the mechanisms underlying this observation may provide insights into the regulation of skeletal maturation. © 2016 American Society for Bone and Mineral Research. © 2016 American Society for Bone and

Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis

International Nuclear Information System (INIS)

Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.; Pierre, Philippe; Chadee, Deborah N.; Pizza, Francis X.

2015-01-01

We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast–myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube–myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube–myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. - Highlights: • We examined mechanisms through which skeletal muscle cell expression of ICAM-1 facilitates events of in vitro myogenesis. • Expression of ICAM-1 by cultured myoblasts did not influence their ability to proliferate or differentiate. • Skeletal muscle cell expression of ICAM-1 augmented myoblast fusion, myotube alignment, myotube–myotube fusion, and myotube size. • ICAM-1 augmented myogenic processes through

Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis

Energy Technology Data Exchange (ETDEWEB)

Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T. [Department of Kinesiology, The University of Toledo, Toledo, OH (United States); Pierre, Philippe [Centre d’Immunologie de Marseille-Luminy U2M, Aix-Marseille Université, Marseille (France); INSERM U631, Institut National de la Santé et Recherche Médicale, Marseille (France); CNRS UMR6102, Centre National de la Recherche Scientifique, Marseille (France); Chadee, Deborah N. [Department of Biological Sciences, The University of Toledo, Toledo, OH (United States); Pizza, Francis X., E-mail: Francis.Pizza@utoledo.edu [Department of Kinesiology, The University of Toledo, Toledo, OH (United States)

2015-02-15

We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast–myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube–myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube–myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. - Highlights: • We examined mechanisms through which skeletal muscle cell expression of ICAM-1 facilitates events of in vitro myogenesis. • Expression of ICAM-1 by cultured myoblasts did not influence their ability to proliferate or differentiate. • Skeletal muscle cell expression of ICAM-1 augmented myoblast fusion, myotube alignment, myotube–myotube fusion, and myotube size. • ICAM-1 augmented myogenic processes through

Selection, processing and clinical application of muscle-skeletal tissue

International Nuclear Information System (INIS)

Luna Z, D.; Reyes F, M.L.; Lavalley E, C.; Castaneda J, G.

2007-01-01

Due to the increase in the average of the world population's life, people die each time to more age, this makes that the tissues of support of the human body, as those muscle-skeletal tissues, when increasing the individual's age go weakening, this in turn leads to the increment of the illnesses like the osteoporosis and the arthritis, that undoubtedly gives as a result more injure of the muscle-skeletal tissues joined a greater number of traffic accidents where particularly these tissues are affected, for that the demand of tissues muscle-skeletal for transplant every day will be bigger. The production of these tissues in the Bank of Radio sterilized Tissues, besides helping people to improve its quality of life saved foreign currencies because most of the muscle-skeletal tissues transplanted in Mexico are of import. The use of the irradiation to sterilize tissues for transplant has shown to be one of the best techniques with that purpose for what the International Atomic Energy Agency believes a Technical cooperation program to establish banks of tissues using the nuclear energy, helping mainly to countries in development. In this work the stages that follows the bank of radio sterilized tissues of the National Institute of Nuclear Research for the cadaverous donor's of muscle-skeletal tissue selection are described, as well as the processing and the clinical application of these tissues. (Author)

Bio-inspired Hybrid Carbon Nanotube Muscles

Science.gov (United States)

Kim, Tae Hyeob; Kwon, Cheong Hoon; Lee, Changsun; An, Jieun; Phuong, Tam Thi Thanh; Park, Sun Hwa; Lima, Márcio D.; Baughman, Ray H.; Kang, Tong Mook; Kim, Seon Jeong

2016-05-01

There has been continuous progress in the development for biomedical engineering systems of hybrid muscle generated by combining skeletal muscle and artificial structure. The main factor affecting the actuation performance of hybrid muscle relies on the compatibility between living cells and their muscle scaffolds during cell culture. Here, we developed a hybrid muscle powered by C2C12 skeletal muscle cells based on the functionalized multi-walled carbon nanotubes (MWCNT) sheets coated with poly(3,4-ethylenedioxythiophene) (PEDOT) to achieve biomimetic actuation. This hydrophilic hybrid muscle is physically durable in solution and responds to electric field stimulation with flexible movement. Furthermore, the biomimetic actuation when controlled by electric field stimulation results in movement similar to that of the hornworm by patterned cell culture method. The contraction and relaxation behavior of the PEDOT/MWCNT-based hybrid muscle is similar to that of the single myotube movement, but has faster relaxation kinetics because of the shape-maintenance properties of the freestanding PEDOT/MWCNT sheets in solution. Our development provides the potential possibility for substantial innovation in the next generation of cell-based biohybrid microsystems.

Skeletal maturation, fundamental motor skills and motor coordination in children 7-10 years.

Science.gov (United States)

Freitas, Duarte L; Lausen, Berthold; Maia, José António; Lefevre, Johan; Gouveia, Élvio Rúbio; Thomis, Martine; Antunes, António Manuel; Claessens, Albrecht L; Beunen, Gaston; Malina, Robert M

2015-01-01

Relationships between skeletal maturation and fundamental motor skills and gross motor coordination were evaluated in 429 children (213 boys and 216 girls) 7-10 years. Skeletal age was assessed (Tanner-Whitehouse 2 method), and stature, body mass, motor coordination (Körperkoordinations Test für Kinder, KTK) and fundamental motor skills (Test of Gross Motor Development, TGMD-2) were measured. Relationships among chronological age, skeletal age (expressed as the standardised residual of skeletal age on chronological age) and body size and fundamental motor skills and motor coordination were analysed with hierarchical multiple regression. Standardised residual of skeletal age on chronological age interacting with stature and body mass explained a maximum of 7.0% of the variance in fundamental motor skills and motor coordination over that attributed to body size per se. Standardised residual of skeletal age on chronological age alone accounted for a maximum of 9.0% of variance in fundamental motor skills, and motor coordination over that attributed to body size per se and interactions between standardised residual of skeletal age on chronological age and body size. In conclusion, skeletal age alone or interacting with body size has a negligible influence on fundamental motor skills and motor coordination in children 7-10 years.

Dental and Skeletal Maturity- A Biological Indicator of Chronologic Age

Science.gov (United States)

Saha, Sonali; Yadav, Gunjan; Tripathi, Abhay Mani; Grover, Kavita

2014-01-01

Introduction: Precise evaluation of the developmental stage of a child is not only an integral part of both diagnosis and treatment of paediatric patients; it is also essential in Forensic Medicine and Dentistry. Physiologic age can be estimated by somatic, sexual, skeletal and dental maturity. Aim: Investigate the relationship between the dental age (DA) and skeletal age (SA) of children and comparing it with the chronological age (CA). Materials and Methods: The dental age estimation methods of Schour and Massler (S&M), and Demirjian and Goldstien (D&G) and skeletal assessment methods of Greulich and Pyle (G&P), and Tanner et al., (TW2) were used to analyze the orthopantomograms and hand-wrist radiographs respectively of 150 healthy subjects within the age range of 5-15 y and compared with the Chronological Age. Statistical Analysis: Data collected was statistically analysed using the SPSS version 15.0 Statistical Analysis Software. For all tests p-value of <0.05 were considered statistically significance. Results: Dental age estimation techniques were found comparable and equally reliable as the skeletal age estimation methods. Strong correlations between dental and skeletal maturation were demonstrated. PMID:25386525

Molecular Mechanisms for Age-Associated Mitochondrial Deficiency in Skeletal Muscle

Directory of Open Access Journals (Sweden)

Akira Wagatsuma

2012-01-01

Full Text Available The abundance, morphology, and functional properties of mitochondria decay in skeletal muscle during the process of ageing. Although the precise mechanisms remain to be elucidated, these mechanisms include decreased mitochondrial DNA (mtDNA repair and mitochondrial biogenesis. Mitochondria possess their own protection system to repair mtDNA damage, which leads to defects of mtDNA-encoded gene expression and respiratory chain complex enzymes. However, mtDNA mutations have shown to be accumulated with age in skeletal muscle. When damaged mitochondria are eliminated by autophagy, mitochondrial biogenesis plays an important role in sustaining energy production and physiological homeostasis. The capacity for mitochondrial biogenesis has shown to decrease with age in skeletal muscle, contributing to progressive mitochondrial deficiency. Understanding how these endogenous systems adapt to altered physiological conditions during the process of ageing will provide a valuable insight into the underlying mechanisms that regulate cellular homeostasis. Here we will summarize the current knowledge about the molecular mechanisms responsible for age-associated mitochondrial deficiency in skeletal muscle. In particular, recent findings on the role of mtDNA repair and mitochondrial biogenesis in maintaining mitochondrial functionality in aged skeletal muscle will be highlighted.

Skeletal Geometry and Indices of Bone Strength in Artistic Gymnasts

Science.gov (United States)

Dowthwaite, Jodi N.; Scerpella, Tamara A.

2010-01-01

This review addresses bone geometry and indices of skeletal strength associated with exposure to gymnastic loading during growth. A brief background characterizes artistic gymnastics as a mechanical loading model and outlines densitometric techniques, skeletal outcomes and challenges in assessment of skeletal adaptation. The literature on bone geometric adaptation to gymnastic loading is sparse and consists of results for disparate skeletal sites, maturity phases, gender compositions and assessment methods, complicating synthesis of an overriding view. Furthermore, most studies assess only females, with little information on males and adults. Nonetheless, gymnastic loading during growth appears to yield significant enlargement of total and cortical bone geometry (+10 to 30%) and elevation of trabecular density (+20%) in the forearm, yielding elevated indices of skeletal strength (+20 to +50%). Other sites exhibit more moderate geometric and densitometric adaptations (5 to 15%). Mode of adaptation appears to be site-specific; some sites demonstrate marked periosteal and endosteal expansion, whereas other sites exhibit negligible or moderate periosteal expansion coupled with endocortical contraction. Further research is necessary to address sex-, maturity- and bone tissue-specific adaptation, as well as maintenance of benefits beyond loading cessation. PMID:19949278

Long-term skeletal findings in Menkes disease

International Nuclear Information System (INIS)

Amador, Eva; Domene, Ruth; Fuentes, Cristian; Carreno, Juan-Carlos; Enriquez, Goya

2010-01-01

Skeletal findings in infants with Menkes disease, the most characteristic of which are metaphyseal spurs, long-bone fractures and wormian bones, have been widely reported. However, the changes in skeletal features over time are not well known. The long-term findings differ completely from those initially observed and consist of undertubulation and metaphyseal flaring, similar to the findings seen in some types of bone dysplasia. The initial and long-term radiological features in an 8-year-old boy with Menkes disease are illustrated. (orig.)

Radiology of postnatal skeletal development. Pt. 6

International Nuclear Information System (INIS)

McCarthy, S.M.; Ogden, J.A.; Yale Univ., New Haven, CT; Yale Univ., New Haven, CT

1982-01-01

Thirty-six pairs of proximal radioulnar and elbow units from cadavers and prepared skeletons ranging in age from full-term neonates to fourteen years, were studied morphologically and roentgenographically. Air/cartilage interfacing was used to demonstrate the osseous and cartilaginous portions of the developing epiphyses. These roentgenographic aspects are discussed and illustrated to provide a reference index. The skeletal development is outlined with regard to the diagnosis of several traumatic skeletal diseases as dislocation of elbow or radial head. Moteggia fracture dislocation and Nursemaid's elbow. (orig./WU)

The role of skeletal muscle in the pathophysiology and management of knee osteoarthritis.

Science.gov (United States)

Krishnasamy, Priathashini; Hall, Michelle; Robbins, Sarah R

2018-05-01

The role of skeletal muscle in the pathophysiology of knee OA is poorly understood. To date, the majority of literature has focused on the association of muscle strength with OA symptoms, disease onset and progression. However, deficits or improvements in skeletal muscle strength do not fully explain the mechanisms behind outcome measures in knee OA, such as pain, function and structural disease. This review aims to summarize components of skeletal muscle, providing a holistic view of skeletal muscle mechanisms that includes muscle function, quality and composition and their interactions. Similarly, the role of skeletal muscle in the management of knee OA will be discussed.

Inward rectifier potassium currents in mammalian skeletal muscle fibres

Science.gov (United States)

DiFranco, Marino; Yu, Carl; Quiñonez, Marbella; Vergara, Julio L

2015-01-01

Inward rectifying potassium (Kir) channels play a central role in maintaining the resting membrane potential of skeletal muscle fibres. Nevertheless their role has been poorly studied in mammalian muscles. Immunohistochemical and transgenic expression were used to assess the molecular identity and subcellular localization of Kir channel isoforms. We found that Kir2.1 and Kir2.2 channels were targeted to both the surface andthe transverse tubular system membrane (TTS) compartments and that both isoforms can be overexpressed up to 3-fold 2 weeks after transfection. Inward rectifying currents (IKir) had the canonical features of quasi-instantaneous activation, strong inward rectification, depended on the external [K+], and could be blocked by Ba2+ or Rb+. In addition, IKir records show notable decays during large 100 ms hyperpolarizing pulses. Most of these properties were recapitulated by model simulations of the electrical properties of the muscle fibre as long as Kir channels were assumed to be present in the TTS. The model also simultaneously predicted the characteristics of membrane potential changes of the TTS, as reported optically by a fluorescent potentiometric dye. The activation of IKir by large hyperpolarizations resulted in significant attenuation of the optical signals with respect to the expectation for equal magnitude depolarizations; blocking IKir with Ba2+ (or Rb+) eliminated this attenuation. The experimental data, including the kinetic properties of IKir and TTS voltage records, and the voltage dependence of peak IKir, while measured at widely dissimilar bulk [K+] (96 and 24 mm), were closely predicted by assuming Kir permeability (PKir) values of ∼5.5 × 10−6 cm s−1 and equal distribution of Kir channels at the surface and TTS membranes. The decay of IKir records and the simultaneous increase in TTS voltage changes were mostly explained by K+ depletion from the TTS lumen. Most importantly, aside from allowing an accurate estimation of

Lipolysis in Skeletal Muscle

DEFF Research Database (Denmark)

Serup, Annette Karen Lundbeck

chemical structure of DAG. We took advantage of the fact that insulin sensitivity is increased after exercise, and that mice knocked out (KO) of HSL accumulate DAG after exercise, and measured insulin stimulated glucose uptake after treadmill running in skeletal muscle from HSL KO mice and wildtype control...

Solitary extra-skeletal sinonasal metastasis from a primary skeletal Ewing's sarcoma.

Science.gov (United States)

Hayes, S M; Jani, T N; Rahman, S M; Jogai, S; Harries, P G; Salib, R J

2011-08-01

Ewing's sarcoma is a rare, malignant tumour predominantly affecting young adolescent males. We describe a unique case of an isolated extra-skeletal metastasis from a skeletal Ewing's sarcoma primary, arising in the right sinonasal cavity of a young man who presented with severe epistaxis and periorbital cellulitis. Histologically, the lesion comprised closely packed, slightly diffuse, atypical cells with round, hyperchromatic nuclei, scant cytoplasm and occasional mitotic figures, arranged in a sheet-like pattern. Immunohistochemical analysis showed positive staining only for cluster of differentiation 99 glycoprotein. Fluorescent in situ hybridisation identified the Ewing's sarcoma gene, confirming the diagnosis. Complete surgical resection was achieved via a minimally invasive endoscopic transnasal approach; post-operative radiotherapy. Ten months post-operatively, there were no endoscopic or radiological signs of disease. Metastatic Ewing's sarcoma within the head and neck is incredibly rare and can pose significant diagnostic and therapeutic challenges. An awareness of different clinical presentations and distinct histopathological features is important to enable early diagnosis. This case illustrates one potential management strategy, and reinforces the evolving role of endoscopic transnasal approaches in managing sinonasal cavity and anterior skull base tumours.

Skeletal muscle tissue transcriptome differences in lean and obese female beagle dogs.

Science.gov (United States)

Grant, R W; Vester Boler, B M; Ridge, T K; Graves, T K; Swanson, K S

2013-08-01

Skeletal muscle is a large and insulin-sensitive tissue that is an important contributor to metabolic homeostasis and energy expenditure. Many metabolic processes are altered with obesity, but the contribution of muscle tissue in this regard is unclear. A limited number of studies have compared skeletal muscle gene expression of lean and obese dogs. Using microarray technology, our objective was to identify genes and functional classes differentially expressed in skeletal muscle of obese (14.6 kg; 8.2 body condition score; 44.5% body fat) vs. lean (8.6 kg; 4.1 body condition score; 22.9% body fat) female beagle adult dogs. Alterations in 77 transcripts was observed in genes pertaining to the functional classes of signaling, transport, protein catabolism and proteolysis, protein modification, development, transcription and apoptosis, cell cycle and differentiation. Genes differentially expressed in obese vs. lean dog skeletal muscle indicate oxidative stress and altered skeletal muscle cell differentiation. Many genes traditionally associated with lipid, protein and carbohydrate metabolism were not altered in obese vs. lean dogs, but genes pertaining to endocannabinoid metabolism, insulin signaling, type II diabetes mellitus and carnitine transport were differentially expressed. The relatively small response of skeletal muscle could indicate that changes are occurring at a post-transcriptional level, that other tissues (e.g., adipose tissue) were buffering skeletal muscle from metabolic dysfunction or that obesity-induced changes in skeletal muscle require a longer period of time and that the length of our study was not sufficient to detect them. Although only a limited number of differentially expressed genes were detected, these results highlight genes and functional classes that may be important in determining the etiology of obesity-induced derangement of skeletal muscle function. © 2013 The Authors, Animal Genetics © 2013 Stichting International Foundation

Radiographically visualized skeletal changes associated with mucopolysaccharidosis VI in cats

International Nuclear Information System (INIS)

Konde, L.J.; Thrall, M.A.; Gasper, P.; Dial, S.M.; McBiles, K.; Colgan, S.; Haskins, M.

1987-01-01

The radiographic skeletal form and structure of all cats with mucopolysaccharidosis VI is described. Common manifestations included epiphyseal dysplasia, generalized osteoporosis, abnormal nasal turbinate development, his subluxation, impaired development of skeletal growth, pectus excavatum, hyoid hypoplasia, aplasia, hypoplasia and fragmentation or abnormal ossification of the dens, and aplasia or hypoplasia of frontal and sphenoid sinuses. The skeletal measurements of two affected cats were compared with those of normal, sex-matched littermates, and the measurements of two affected female cats were compared with those of a normal male littermate

Effects of hypodynamic simulations on the skeletal system of monkeys

Science.gov (United States)

Young, D. R.; Tremor, J. W.

1977-01-01

A research and development program was undertaken to evaluate the skeletal losses of subhuman primates in hypodynamic environments. The goals of the program are: (1) to uncover the mechanisms by which weightlessness affects the skeletal system; (2) to determine the consequences and reversibility of bone mineral losses; and (3) to acquire a body of data needed to formulate an appropriate countermeasure program for the prevention of skeletal deconditioning. Space flight experiment simulation facilities are under development and will be tested for their capability in supporting certain of the requirements for these investigations.

Direct effects of doxorubicin on skeletal muscle contribute to fatigue

NARCIS (Netherlands)

Norren, van K.; Helvoort, van A.; Argiles, J.M.; Tuijl, van S.; Arts, K.; Gorselink, M.; Laviano, A.; Kegler, D.; Haagsman, H.P.; Beek, E.M.

2009-01-01

Chemotherapy-induced fatigue is a multidimensional symptom. Oxidative stress has been proposed as a working mechanism for anthracycline-induced cardiotoxicity. In this study, doxorubicin (DOX) was tested on skeletal muscle function. Doxorubicin induced impaired ex vivo skeletal muscle relaxation

In vitro effects of oxytocin, acepromazine, detomidine, xylazine, butorphanol, terbutaline, isoproterenol, and dantrolene on smooth and skeletal muscles of the equine esophagus.

Science.gov (United States)

Wooldridge, Anne A; Eades, Susan C; Hosgood, Giselle L; Moore, Rustin M

2002-12-01

To characterize the in vitro effects of oxytocin, acepromazine, xylazine, butorphanol, detomidine, dantrolene, isoproterenol, and terbutaline on skeletal and smooth muscle from the equine esophagus. 14 adult horses without digestive tract disease. Circular and longitudinal strips from the skeletal and smooth muscle of the esophagus were suspended in tissue baths, connected to force-displacement transducers interfaced with a physiograph, and electrical field stimulation was applied. Cumulative concentration-response curves were generated for oxytocin, acepromazine, xylazine, detomidine, butorphanol, isoproterenol, terbutaline, and dantrolene. Mean maximum twitch amplitude for 3 contractions/min was recorded and compared with predrug-vehicle values for the skeletal muscle segments, and area under the curve (AUC) for 3 contractions/min was compared with predrug-vehicle values for the smooth muscle segments. No drugs caused a significant change in skeletal muscle response. In smooth muscle, isoproterenol, terbutaline, and oxytocin significantly reduced AUC in a concentration-dependent manner. Maximum reduction in AUC was 69% at 10(-4) M for isoproterenol, 63% at 10(-6) M for terbutaline, and 64% at 10(-4) M for oxytocin. Isoproterenol, terbutaline, and oxytocin cause relaxation of the smooth muscle portion of the esophagus. The clinical relaxant effects on the proximal portion of the esophagus reported of drugs such as oxytocin, detomidine, and acepromazine may be the result of centrally mediated mechanisms.

Simvastatin effects on skeletal muscle

DEFF Research Database (Denmark)

Larsen, Steen; Stride, Nis; Hey-Mogensen, Martin

2013-01-01

Glucose tolerance and skeletal muscle coenzyme Q(10) (Q(10)) content, mitochondrial density, and mitochondrial oxidative phosphorylation (OXPHOS) capacity were measured in simvastatin-treated patients (n = 10) and in well-matched control subjects (n = 9)....

Effects of acute exercise on gene expression in exercising and non-exercising human skeletal muscle

NARCIS (Netherlands)

Catoire, Milene; Mensink, Marco; Boekschoten, Mark; Hangelbroek, Roland; Muller, Michael; Schrauwen, Patricht; Kersten, Sander

2012-01-01

Background: Exercising is know to have an effect on exercising skeletal muscle, but unkown is the effect on non-exercising skeletal muscle. Gene expression changes in the non-exercising skeletal muscle would point to a signalling role of skeletal muscle

Skeletal muscle stem cells from animals I. Basic cell biology

Science.gov (United States)

Skeletal muscle stem cells from food-producing animals have been of interest to agricultural life scientists seeking to develop a better understanding of the molecular regulation of lean tissue (skeletal muscle protein hypertrophy) and intramuscular fat (marbling) development. Enhanced understanding...

Pharyngeal airway dimensions in skeletal class II: A cephalometric growth study

International Nuclear Information System (INIS)

Uslu-Akcam, Ozge

2017-01-01

This retrospective study aimed to evaluate the nasopharyngeal and oropharyngeal dimensions of individuals with skeletal class II, division 1 and division 2 patterns during the pre-peak, peak, and post-peak growth periods for comparison with a skeletal class I control group. Totally 124 lateral cephalograms (47 for skeletal class I; 45 for skeletal class II, division 1; and 32 for skeletal class II, division 2) in pre-peak, peak, and post-peak growth periods were selected from the department archives. Thirteen landmarks, 4 angular and 4 linear measurements, and 4 proportional calculations were obtained. The ANOVA and Duncan test were applied to compare the differences among the study groups during the growth periods. Statistically significant differences were found between the skeletal class II, division 2 group and other groups for the gonion-gnathion/sella-nasion angle. The sella-nasion-B-point angle was different among the groups, while the A-point-nasion-B-point angle was significantly different for all 3 groups. The nasopharyngeal airway space showed a statistically significant difference among the groups throughout the growth periods. The interaction among the growth periods and study groups was statistically significant regarding the upper oropharyngeal airway space measurement. The lower oropharyngeal airway space measurement showed a statistically significant difference among the groups, with the smallest dimension observed in the skeletal class II, division 2 group. The naso-oropharyngeal airway dimensions showed a statistically significant difference among the class II, division 1; class II, division 2; and class I groups during different growth periods

A radiographic study of temporomandibular joints in skeletal class III malocclusion

International Nuclear Information System (INIS)

Kim, Sung Eun; Kim, Kae Duk

2003-01-01

To investigate the differences between the position of the mandibular condyles in temporomandibular joints of patients presenting with normal occlusion and skeletal class III malocclusion. Forty-two subjects with normal occlusion and thirty-seven subjects exhibiting skeletal class III malocclusion prior to orthodontic treatment were included in the study. Transcranial radiographs of each subject were taken at centric occlusion and 1 inch mouth opening. The positional relationship between the mandibular condyles with articular fossae and articular eminences at two positional states were evaluated and analyzed statistically. The mandibular condyles of the skeletal class III malocclusion group were found to be located more anteriorly from the center of the articular fossae compared to the normal occlusion group in centric occlusion. The mandibular condyles of the skeletal Class III malocclusion group were located more superiorly from the middle of articular height than those of the normal occlusion group in centric occlusion. However, these differences were not statistically significant. At 1 inch mouth opening, the mandibular condyles of the skeletal class III malocclusion group were placed more posteriorly from the articular eminences than those of the normal occlusion group. The mean angle of the articular eminence posterior slope were 56.51 .deg. ± 6.29 .deg. in the normal occlusion group and 60.37 .deg. ± 6.26 .deg. in the skeletal Class III malocclusion group. The mandibular condyles of the skeletal Class III malocclusion group were placed more anteriorly at centric occlusion and more posteriorly at 1 inch mouth opening when compared with those of the normal occlusion group.

Pharyngeal airway dimensions in skeletal class II: A cephalometric growth study

Energy Technology Data Exchange (ETDEWEB)

Uslu-Akcam, Ozge [Clinic of Orthodontics, Ministry of Health, Tepebasi Oral and Dental Health Hospital, Ankara (Turkmenistan)

2017-03-15

This retrospective study aimed to evaluate the nasopharyngeal and oropharyngeal dimensions of individuals with skeletal class II, division 1 and division 2 patterns during the pre-peak, peak, and post-peak growth periods for comparison with a skeletal class I control group. Totally 124 lateral cephalograms (47 for skeletal class I; 45 for skeletal class II, division 1; and 32 for skeletal class II, division 2) in pre-peak, peak, and post-peak growth periods were selected from the department archives. Thirteen landmarks, 4 angular and 4 linear measurements, and 4 proportional calculations were obtained. The ANOVA and Duncan test were applied to compare the differences among the study groups during the growth periods. Statistically significant differences were found between the skeletal class II, division 2 group and other groups for the gonion-gnathion/sella-nasion angle. The sella-nasion-B-point angle was different among the groups, while the A-point-nasion-B-point angle was significantly different for all 3 groups. The nasopharyngeal airway space showed a statistically significant difference among the groups throughout the growth periods. The interaction among the growth periods and study groups was statistically significant regarding the upper oropharyngeal airway space measurement. The lower oropharyngeal airway space measurement showed a statistically significant difference among the groups, with the smallest dimension observed in the skeletal class II, division 2 group. The naso-oropharyngeal airway dimensions showed a statistically significant difference among the class II, division 1; class II, division 2; and class I groups during different growth periods.

A radiographic study of temporomandibular joints in skeletal class III malocclusion

Energy Technology Data Exchange (ETDEWEB)

Kim, Sung Eun; Kim, Kae Duk [Chosun University College of Medicine, Kwangju (Korea, Republic of)

2003-06-15

To investigate the differences between the position of the mandibular condyles in temporomandibular joints of patients presenting with normal occlusion and skeletal class III malocclusion. Forty-two subjects with normal occlusion and thirty-seven subjects exhibiting skeletal class III malocclusion prior to orthodontic treatment were included in the study. Transcranial radiographs of each subject were taken at centric occlusion and 1 inch mouth opening. The positional relationship between the mandibular condyles with articular fossae and articular eminences at two positional states were evaluated and analyzed statistically. The mandibular condyles of the skeletal class III malocclusion group were found to be located more anteriorly from the center of the articular fossae compared to the normal occlusion group in centric occlusion. The mandibular condyles of the skeletal Class III malocclusion group were located more superiorly from the middle of articular height than those of the normal occlusion group in centric occlusion. However, these differences were not statistically significant. At 1 inch mouth opening, the mandibular condyles of the skeletal class III malocclusion group were placed more posteriorly from the articular eminences than those of the normal occlusion group. The mean angle of the articular eminence posterior slope were 56.51 .deg. {+-} 6.29 .deg. in the normal occlusion group and 60.37 .deg. {+-} 6.26 .deg. in the skeletal Class III malocclusion group. The mandibular condyles of the skeletal Class III malocclusion group were placed more anteriorly at centric occlusion and more posteriorly at 1 inch mouth opening when compared with those of the normal occlusion group.

The HO-1/CO system regulates mitochondrial-capillary density relationships in human skeletal muscle.

Science.gov (United States)

Pecorella, Shelly R H; Potter, Jennifer V F; Cherry, Anne D; Peacher, Dionne F; Welty-Wolf, Karen E; Moon, Richard E; Piantadosi, Claude A; Suliman, Hagir B

2015-10-15

The heme oxygenase-1 (HO-1)/carbon monoxide (CO) system induces mitochondrial biogenesis, but its biological impact in human skeletal muscle is uncertain. The enzyme system generates CO, which stimulates mitochondrial proliferation in normal muscle. Here we examined whether CO breathing can be used to produce a coordinated metabolic and vascular response in human skeletal muscle. In 19 healthy subjects, we performed vastus lateralis muscle biopsies and tested one-legged maximal O2 uptake (V̇o2max) before and after breathing air or CO (200 ppm) for 1 h daily for 5 days. In response to CO, there was robust HO-1 induction along with increased mRNA levels for nuclear-encoded mitochondrial transcription factor A (Tfam), cytochrome c, cytochrome oxidase subunit IV (COX IV), and mitochondrial-encoded COX I and NADH dehydrogenase subunit 1 (NDI). CO breathing did not increase V̇o2max (1.96 ± 0.51 pre-CO, 1.87 ± 0.50 post-CO l/min; P = not significant) but did increase muscle citrate synthase, mitochondrial density (139.0 ± 34.9 pre-CO, 219.0 ± 36.2 post-CO; no. of mitochondrial profiles/field), myoglobin content and glucose transporter (GLUT4) protein level and led to GLUT4 localization to the myocyte membrane, all consistent with expansion of the tissue O2 transport system. These responses were attended by increased cluster of differentiation 31 (CD31)-positive muscle capillaries (1.78 ± 0.16 pre-CO, 2.37 ± 0.59 post-CO; capillaries/muscle fiber), implying the enrichment of microvascular O2 reserve. The findings support that induction of the HO-1/CO system by CO not only improves muscle mitochondrial density, but regulates myoglobin content, GLUT4 localization, and capillarity in accordance with current concepts of skeletal muscle plasticity. Copyright © 2015 the American Physiological Society.

In utero undernutrition programs skeletal and cardiac muscle metabolism

Directory of Open Access Journals (Sweden)

Brittany eBeauchamp

2016-01-01

Full Text Available In utero undernutrition is associated with increased risk for insulin resistance, obesity, and cardiovascular disease during adult life. A common phenotype associated with low birth weight is reduced skeletal muscle mass. Given the central role of skeletal muscle in whole body metabolism, alterations in its mass as well as its metabolic characteristics may contribute to disease risk. This review highlights the metabolic alterations in cardiac and skeletal muscle associated with in utero undernutrition and low birth weight. These tissues have high metabolic demands and are known to be sites of major metabolic dysfunction in obesity, type 2 diabetes, and cardiovascular disease. Recent research demonstrates that mitochondrial energetics are decreased in skeletal and cardiac muscles of adult offspring from undernourished mothers. These effects apparently lead to the development of a thrifty phenotype, which may represent overall a compensatory mechanism programmed in utero to handle times of limited nutrient availability. However, in an environment characterized by food abundance, the effects are maladaptive and increase adulthood risks of metabolic disease.

Self-Adhesive and Capacitive Carbon Nanotube-Based Electrode to Record Electroencephalograph Signals From the Hairy Scalp.

Science.gov (United States)

Lee, Seung Min; Kim, Jeong Hun; Park, Cheolsoo; Hwang, Ji-Young; Hong, Joung Sook; Lee, Kwang Ho; Lee, Sang Hoon

2016-01-01

We fabricated a carbon nanotube (CNT)/adhesive polydimethylsiloxane (aPDMS) composite-based dry electroencephalograph (EEG) electrode for capacitive measuring of EEG signals. As research related to brain-computer interface applications has advanced, the presence of hairs on a patient's scalp has continued to present an obstacle to recorder EEG signals using dry electrodes. The CNT/aPDMS electrode developed here is elastic, highly conductive, self-adhesive, and capable of making conformal contact with and attaching to a hairy scalp. Onto the conductive disk, hundreds of conductive pillars coated with Parylene C insulation layer were fabricated. A CNT/aPDMS layer was attached on the disk to transmit biosignals to the pillar. The top of disk was designed to be solderable, which enables the electrode to connect with a variety of commercial EEG acquisition systems. The mechanical and electrical characteristics of the electrode were tested, and the performances of the electrodes were evaluated by recording EEGs, including alpha rhythms, auditory-evoked potentials, and steady-state visually-evoked potentials. The results revealed that the electrode provided a high signal-to-noise ratio with good tolerance for motion. Almost no leakage current was observed. Although preamplifiers with ultrahigh input impedance have been essential for previous capacitive electrodes, the EEGs were recorded here by directly connecting a commercially available EEG acquisition system to the electrode to yield high-quality signals comparable to those obtained using conventional wet electrodes.

Suspected fetal skeletal malformations or bone diseases: how to explore

International Nuclear Information System (INIS)

Cassart, Marie

2010-01-01

Skeletal dysplasias are a heterogeneous and complex group of conditions that affect bone growth and development and result in various anomalies in shape and size of the skeleton. Although US has proved reliable for the prenatal detection of skeletal abnormalities, the precise diagnosis of a dysplasia is often difficult to make before birth (especially in the absence of a familial history) due to their various phenotypic presentations, the variability in the time at which they manifest and often, the lack of precise molecular diagnosis. In addition to the accuracy of the antenatal diagnosis, it is very important to establish a prognosis. This is a clinically relevant issue as skeletal dysplasias may be associated with severe disability and may even be lethal. We will therefore describe the respective role of two-dimensional (2-D) US, three-dimensional (3-D) US and CT in the antenatal assessment of skeletal malformations. (orig.)

The diagnostic performance of chronologic age in the assessment of skeletal maturity.

Science.gov (United States)

Baccetti, Tiziano; Franchi, Lorenzo; De Toffol, Laura; Ghiozzi, Bruno; Cozza, Paola

2006-01-01

The aim of this study was to analyze the relationship between chronologic age the and individual skeletal maturity as assessed by means of the cervical vertebral maturation (CVM) method during the circumpubertal period. The evaluated sample of 600 subjects consisted of 100 subjects (50 males and 50 females) for each of 6 age groups, from 9 years through 14 years of age. Individual skeletal maturity for all subjects was determined by using the CVM method. The relationship between chronologic age and the most prevalent CVM stage at each age group was evaluated statistically by means of indicators of diagnostic test performance that specify the ability of a diagnostic test to identify a condition. The diagnostic performance of chronologic age for the detection of the onset of the adolescent peak in skeletal maturation was very low both in males and in females. In male subjects, the chronologic age of 9 years +/- 6 months presented with strong diagnostic power for the identification of a pre-pubertal stage in skeletal maturation. In female subjects, the chronologic age of 14 years +/- 6 months corresponded with a strong probability of a postpubertal stage in skeletal maturation. In males, chronologic age can identify a pre-pubertal stage of skeletal development, and in females a post-pubertal stage. In both males and females, chronologic age cannot recognize the onset of the adolescent peak in skeletal maturation.

Comprehensive Validation of Skeletal Mechanism for Turbulent Premixed Methane–Air Flame Simulations

KAUST Repository

Luca, Stefano

2017-08-01

A new skeletal mechanism, consisting of 16 species and 72 reactions, has been developed for lean methane–air premixed combustion from the GRI-Mech 3.0. The skeletal mechanism is validated for elevated unburnt temperatures (800 K) and pressures up to 4 atm, thereby addressing realistic gas turbine conditions. The skeletal mechanism is obtained by applying the directed relation graph method and performing sensitivity analysis on the detailed mechanism. The mechanism has been validated for flame speed and flame structure in a wide range of conditions and configurations. A good agreement between the skeletal mechanism and GRI-3.0 was obtained. The configurations considered include one-dimension laminar premixed flames, laminar non-premixed counterflow burners, and two- and three-dimensional unsteady configurations with variations of temperature, pressure, and composition. The skeletal mechanism allows for the inclusion of accurate finite rate chemistry in large-scale direct numerical simulations of lean turbulent premixed flames. In a large-scale direct numerical simulation, the use of the skeletal mechanism reduces the memory requirements by more than a factor of 3 and accelerates the simulation by a factor of 7 compared with the detailed mechanism. The skeletal mechanism is suitable for unsteady three-dimensional simulations of methane turbulent premixed, non-premixed, and globally lean partially premixed flames and is available as supplementary material.

Decadal climate variation recorded in modern global carbonate archives (brachiopods, molluscs)

Science.gov (United States)

Romanin, Marco; Zaki, Amir H.; Davis, Alyssa; Shaver, Kristen; Wang, Lisha; Aleksandra Bitner, Maria; Capraro, Luca; Preto, Nereo; Brand, Uwe

2017-04-01

The progress of the Earth's warming trend has rapidly accelerated in the last few decades due to the increase in emission of anthropogenic greenhouse gases. The exchange of heat between the atmosphere and seawater has consequently elevated the rate of temperature buildup in the low and high latitude ocean. Records of the variation in seawater temperature in response to local and global changes in climate are preserved within the carbonate structures of marine biogenic archives. Investigating the isotopic composition of the archives' growth increments documents the magnitude of sea surface temperature (SST) change. A long-term (1956-2012) record of temperature change in sub-tropical seawater was acquired from the giant clam Tridacna maxima collected from the Red Sea in conjunction with published results of the oyster Hyotissa hyotis (Titschack et al., 2010). Variation in polar-subpolar SST was obtained from the brachiopod Magellania venosa recovered from the coastal area of southern Chile, and from the proxy record of Hemithiris psittacea of Hudson Bay (Brand et al., 2014). The former reveals a long-term (1961-2012) time-series of Antarctic-induced oceanographic change in the southern hemisphere, while the latter represents a trend of Hudson Bay seawater SST in the northern hemisphere. Evaluation of the isotopic compositions confirms the equilibrium incorporation of oxygen isotopes with respect to ambient seawater in brachiopods and some bivalves. A general trend of decreasing δ18O values in the Red Sea molluscs is observed, indicating an increase in tropical seawater temperature of about 0.79°C since 1988. The δ18O values of the polar-subpolar brachiopods display similar depletion slopes but of larger magnitudes than that of the Red Sea archives. This signifies a rise in seawater temperature of about 1.47°C in Hudson Bay since 1991, and about 2.08°C in southern Chile since 1988. The 2013 IPCC report suggests an increase in SST of +0.094°C per decade (average

Structural, biochemical, cellular, and functional changes in skeletal muscle extracellular matrix with aging

DEFF Research Database (Denmark)

Kragstrup, T W; Kjaer, M; Mackey, A L

2011-01-01

The extracellular matrix (ECM) of skeletal muscle is critical for force transmission and for the passive elastic response of skeletal muscle. Structural, biochemical, cellular, and functional changes in skeletal muscle ECM contribute to the deterioration in muscle mechanical properties with aging....... Structural changes include an increase in the collagen concentration, a change in the elastic fiber system, and an increase in fat infiltration of skeletal muscle. Biochemical changes include a decreased turnover of collagen with potential accumulation of enzymatically mediated collagen cross...

Alterations in the morphology of skeletal myofibres after 90 minutes ...

African Journals Online (AJOL)

Alterations in the morphology of skeletal myofibres after 90 minutes of ischaemia and '- 3 hours of reperfusion. M.A. Gregory, M. Mars. Abstract. Morphometric, light and electron microscopic methods were employed to determine whether skeletal myofibres were damaged by 90 minutes of tourniquet-mediated ischaemia.

How is AMPK activity regulated in skeletal muscles during exercise?

DEFF Research Database (Denmark)

Jørgensen, Sebastian Beck; Rose, Adam John

2008-01-01

AMPK is a metabolic "master" controller activated in skeletal muscle by exercise in a time and intensity dependent manner, and has been implicated in regulating metabolic pathways in muscle during physical exercise. AMPK signaling in skeletal muscle is regulated by several systemic...... and intracellular factors and the regulation of skeletal muscle AMPK in response to exercise is the focus of this review. Specifically, the role of LKB1 and phosphatase PP2C in nucleotide-dependent activation of AMPK, and ionized calcium in CaMKK-dependent activation of AMPK in working muscle is discussed. We also...

The skeletal consequences of thyrotoxicosis.

Science.gov (United States)

Nicholls, Jonathan J; Brassill, Mary Jane; Williams, Graham R; Bassett, J H Duncan

2012-06-01

Euthyroid status is essential for normal skeletal development and the maintenance of adult bone structure and strength. Established thyrotoxicosis has long been recognised as a cause of high bone turnover osteoporosis and fracture but more recent studies have suggested that subclinical hyperthyroidism and long-term suppressive doses of thyroxine (T4) may also result in decreased bone mineral density (BMD) and an increased risk of fragility fracture, particularly in postmenopausal women. Furthermore, large population studies of euthyroid individuals have demonstrated that a hypothalamic-pituitary-thyroid axis set point at the upper end of the normal reference range is associated with reduced BMD and increased fracture susceptibility. Despite these findings, the cellular and molecular mechanisms of thyroid hormone action in bone remain controversial and incompletely understood. In this review, we discuss the role of thyroid hormones in bone and the skeletal consequences of hyperthyroidism.

Value of fetal skeletal radiographs in the diagnosis of fetal death

International Nuclear Information System (INIS)

Bourliere-Najean, B.; Russel, A.S.; Petit, P.; Devred, P.; Panuel, M.; Piercecchi-Marti, M.D.; Fredouille, C.; Sigaudy, S.; Philip, N.

2003-01-01

The aim of this study was to assess the value of fetal skeletal radiographs in determining the etiology of fetal death. A total of 1193 post-mortem fetal skeletal radiographs were analysed. Fetuses were classified into one of three groups (group I: abnormality diagnosed during pregnancy; group II: maternal pathology; group III: spontaneous abortion of pregnancy, IIIa before 26 weeks of gestation (WG), IIIb after 26 weeks of gestation). Face, supine and lateral skeletal views were performed. Skeletal abnormalities were detected in 33.9% of the fetuses, including 22.7% with minor abnormalities (abnormal rib number, no nasal bone ossification, amesophalangia or P2 hypoplasia of the fifth digit) and 14.5% with major abnormalities (other skeletal abnormalities). Among the fetuses with major abnormalities, 98.8% came from group I, 2.9% came from group II, 2.3% came from group IIIa and none came from group IIIb. Fetal skeletal radiographs are not useful in fetuses arising from spontaneous abortion of pregnancy without abnormality on ultrasound screening, abnormality clinical examination or in fetuses with prenatal diagnosis of chromosomal abnormality. This practice is valuable only if there is a multidisciplinary team, with all the participants (pathologists, radiologists, geneticists) knowledgeable about fetal pathology. In the absence of this multidisciplinary approach, it is easier to X-ray all fetuses to avoid misdiagnosis and the important consequences for genetic counselling. (orig.)

Diabetic Myopathy: Impact of Diabetes Mellitus on Skeletal Muscle Progenitor Cells

Directory of Open Access Journals (Sweden)

Donna M D'Souza

2013-12-01

Full Text Available Diabetes mellitus is defined as a group of metabolic diseases that are associated with the presence of a hyperglycemic state due to impairments in insulin function. While the development of each form of diabetes (Type 1 or Type 2 drastically differs, resultant pathologies often overlap. In each diabetic condition a failure to maintain healthy muscle is often observed, and is termed diabetic myopathy. This significant, but often overlooked, complication is believed to contribute to the progression of additional diabetic pathologies due to the vital importance of skeletal muscle for our physical and metabolic well-being. While studies have investigated the link between changes to skeletal muscle metabolic health following diabetes mellitus onset (particularly Type 2 diabetes mellitus, few have examined the negative impact of diabetes mellitus on the growth and reparative capacities of skeletal muscle that often coincides with disease development. Importantly, evidence is accumulating that the muscle progenitor cell population (particularly the muscle satellite cell population is also negatively affected by the diabetic environment, and as such, likely contributes to the declining skeletal muscle health observed in diabetes mellitus. In this review, we summarize the current knowledge surrounding the influence of diabetes mellitus on skeletal muscle growth and repair, with a particular emphasis on the impact of diabetes mellitus on the progenitor cell population of skeletal muscle.

Value of fetal skeletal radiographs in the diagnosis of fetal death

Energy Technology Data Exchange (ETDEWEB)

Bourliere-Najean, B.; Russel, A.S.; Petit, P.; Devred, P. [Department of Pediatric Radiology, CHU Timone, 264 rue St. Pierre, 13385 Marseille cedex 5 (France); Panuel, M. [Department of Radiology, Hopital Nord, chemin Bourrelys, 13915 Marseille cedex 20 (France); Piercecchi-Marti, M.D.; Fredouille, C. [Department of Pathology, CHU Timone, 264 rue St. Pierre, 13385 Marseille cedex 5 (France); Sigaudy, S.; Philip, N. [Department of Genetics, CHU Timone, 264 rue St. Pierre, 13385 Marseille cedex 5 (France)

2003-05-01

The aim of this study was to assess the value of fetal skeletal radiographs in determining the etiology of fetal death. A total of 1193 post-mortem fetal skeletal radiographs were analysed. Fetuses were classified into one of three groups (group I: abnormality diagnosed during pregnancy; group II: maternal pathology; group III: spontaneous abortion of pregnancy, IIIa before 26 weeks of gestation (WG), IIIb after 26 weeks of gestation). Face, supine and lateral skeletal views were performed. Skeletal abnormalities were detected in 33.9% of the fetuses, including 22.7% with minor abnormalities (abnormal rib number, no nasal bone ossification, amesophalangia or P2 hypoplasia of the fifth digit) and 14.5% with major abnormalities (other skeletal abnormalities). Among the fetuses with major abnormalities, 98.8% came from group I, 2.9% came from group II, 2.3% came from group IIIa and none came from group IIIb. Fetal skeletal radiographs are not useful in fetuses arising from spontaneous abortion of pregnancy without abnormality on ultrasound screening, abnormality clinical examination or in fetuses with prenatal diagnosis of chromosomal abnormality. This practice is valuable only if there is a multidisciplinary team, with all the participants (pathologists, radiologists, geneticists) knowledgeable about fetal pathology. In the absence of this multidisciplinary approach, it is easier to X-ray all fetuses to avoid misdiagnosis and the important consequences for genetic counselling. (orig.)

Radiation treatment of painful degenerative skeletal conditions

International Nuclear Information System (INIS)

Schaefer, U.; Micke, O.; Willich, N.

1996-01-01

The study reported was intended to present own experience with irradiation for treatment of painful degenerative skeletal conditions and examine the long-term effects of this treatment. A retrospective study was performed covering the period from 1985 until 1991, examining 157 patients suffering from painful degenerative skeletal conditions who entered information on the success of their radiation treatment in a questionnaire. 94 of the questionnaires could be used for evaluation. Pain anamnesis revealed periods of more than one year in 45% of the cases. 74% of the patients had been treated without success with drug or orthopedic therapy. Immediately after termination of the radiotherapy, 38% of the patients said to be free of pain or to feel essentially relieved, while at the time the questionnaire was distributed, the percentage was 76%. Thus in our patient material, radiotherapy for treatment of painful degenerative skeletal lesions was successful in 76% of the cases and for long post-treatment periods, including those cases whith long pain anamnesis and unsuccessful conventional pre-treatment. (orig./MG) [de

Skeletal stem cells and their contribution to skeletal fragility

DEFF Research Database (Denmark)

Aldahmash, A.

2016-01-01

Age-related osteoporotic fractures are major health care problem worldwide and are the result of impaired bone formation, decreased bone mass and bone fragility. Bone formation is accomplished by skeletal stem cells (SSC) that are recruited to bone surfaces from bone marrow microenvironment....... This review discusses targeting SSC to enhance bone formation and to abolish age-related bone fragility in the context of using stem cells for treatment of age-related disorders. Recent studies are presented that have demonstrated that SSC exhibit impaired functions during aging due to intrinsic senescence...

Serum levo-carnitine levels and skeletal muscle functions in type 2 diabetes mellitus in rodents

International Nuclear Information System (INIS)

Aleem, S.B.; Hussain, M.M.; Farooq, Y.

2013-01-01

Objective: To study serum levo-carnitine (l-carnitine) levels and isometric contraction, force frequency relationship and fatigue of rodent skeletal muscles in type 2 diabetes mellitus. Study Design: Randomized controlled trial. Place and Duration of Study: Physiology Department, Army Medical College, Rawalpindi, from January 2009 to January 2010. Methodology: Sixty Sprague-Dawley rats were randomly divided into two groups; group I (control), fed on normal diet ad libitum and Group II (diabetic), fed on high fat diet and administered streptozocin to induce type 2 diabetes mellitus (T2DM). At 21st day, plasma glucose and TG/HDL ratio were measured to confirm the development of T2DM in group II. At 28th day, blood was drawn by intracardiac puncture to estimate serum levo-carnitine levels. Contractile functions of skeletal muscles were assessed by using iWorx AHK/214 physiological data acquisition unit. Simple muscle twitches, maximum isometric twitch tension (MITT), time-to-peak twitch tension (TPTT) and time-to-relax to 50% of the peak twitch tension (1/2RT) of extensor digitorum muscles were recorded. Muscles were stimulated at higher frequencies to determine maximum fused tetanic tension (MFTT), maximum fused tetanic tension after fatigue protocol (TTFP) and recovery from fatigue (RF). Results: Serum levo-carnitine level decreased significantly in the diabetic group. Both groups had similar MITT, TPTT and 1/2RT but decline in MFTT, TTFP and RF was significant in the diabetic rats. Conclusion: T2DM adversely affected serum levo-carnitine levels and the contractile functions of rodent skeletal muscle at high frequency stimulation. (author)

Establishment and cryopreservation of a giant panda skeletal muscle-derived cell line.

Science.gov (United States)

Yu, Fang-Jian; Zeng, Chang-Jun; Zhang, Yan; Wang, Cheng-Dong; Xiong, Tie-Yi; Fang, Sheng-Guo; Zhang, He-Min

2015-06-01

The giant panda Ailuropoda melanoleuca is an endangered species and is a symbol for wildlife conservation. Although efforts have been made to protect this rare and endangered species through breeding and conservative biology, the long-term preservation of giant panda genome resources (gametes, tissues, organs, genomic libraries, etc.) is still a practical option. In this study, the giant panda skeletal muscle-derived cell line was successfully established via primary explants culture and cryopreservation techniques. The population doubling time of giant panda skeletal cells was approximately 33.8 h, and this population maintained a high cell viability before and after cryopreservation (95.6% and 90.7%, respectively). The two skeletal muscle-specific genes SMYD1 and MYF6 were expressed and detected by RT-PCR in the giant panda skeletal muscle-derived cell line. Karyotyping analysis revealed that the frequencies of giant panda skeletal muscle cells showing a chromosome number of 2n=42 ranged from 90.6∼94.2%. Thus, the giant panda skeletal muscle-derived cell line provides a vital resource and material platform for further studies and is likely to be useful for the protection of this rare and endangered species.

Tracing the evolutionary origin of vertebrate skeletal tissues: insights from cephalochordate amphioxus.

Science.gov (United States)

Yong, Luok Wen; Yu, Jr-Kai

2016-08-01

Vertebrate mineralized skeletal tissues are widely considered as an evolutionary novelty. Despite the importance of these tissues to the adaptation and radiation of vertebrate animals, the evolutionary origin of vertebrate skeletal tissues remains largely unclear. Cephalochordates (Amphioxus) occupy a key phylogenetic position and can serve as a valuable model for studying the evolution of vertebrate skeletal tissues. Here we summarize recent advances in amphioxus developmental biology and comparative genomics that can help to elucidate the evolutionary origins of the vertebrate skeletal tissues and their underlying developmental gene regulatory networks (GRN). By making comparisons to the developmental studies in vertebrate models and recent discoveries in paleontology and genomics, it becomes evident that the collagen matrix-based connective tissues secreted by the somite-derived cells in amphioxus likely represent the rudimentary skeletal tissues in chordates. We propose that upon the foundation of this collagenous precursor, novel tissue mineralization genes that arose from gene duplications were incorporated into an ancestral mesodermal GRN that makes connective and supporting tissues, leading to the emergence of highly-mineralized skeletal tissues in early vertebrates. Copyright © 2016 Elsevier Ltd. All rights reserved.

New Skeletal-Space-Filling Models

Science.gov (United States)

Clarke, Frank H.

1977-01-01

Describes plastic, skeletal molecular models that are color-coded and can illustrate both the conformation and overall shape of small molecules. They can also be converted to space-filling counterparts by the additions of color-coded polystyrene spheres. (MLH)

Story of skeletally substituted benzenes

Indian Academy of Sciences (India)

Unknown

values are extensively used to define aromaticity quantitatively.3 In a recent study on ... studies were directed to unravel the subtle ways in which the stability, reactivity, and ..... The singlet–triplet gaps of all the skeletally substituted benzenes ...

Mitochondrial biogenesis and angiogenesis in skeletal muscle of the elderly

DEFF Research Database (Denmark)

Iversen, Ninna; Krustrup, Peter; Rasmussen, Hans N

2011-01-01

The aim of this study was to test the hypotheses that 1) skeletal muscles of elderly subjects can adapt to a single endurance exercise bout and 2) endurance trained elderly subjects have higher expression/activity of oxidative and angiogenic proteins in skeletal muscle than untrained elderly peop...

Chance findings in skeletal radiology; Zufallsbefunde in der Skelettradiologie

Energy Technology Data Exchange (ETDEWEB)

Freyschmidt, Juergen [Beratungsstelle und Referenzzentrum fuer Osteoradiologie, Bremen (Germany)

2016-08-01

The book on chance findings in skeletal radiology covers the following issues: Part (I): Introduction - what are chance findings? Part (II); change findings under different radiological modalities: most frequent skeletal radiological change findings: scintiscanning, radiography and CT, MRT, PET and PET/CT. Part (III): case studies: skull; spinal cord; shoulder/pectoral girdle, chest; pelvis and hip joints; upper extremities; lower extremities.

Haematological, ocular and skeletal abnormalities in a Samoyed family

International Nuclear Information System (INIS)

Aroch, I.; Ofri, R.; Aizenberg, I.

1996-01-01

Haematological, ocular and skeletal abnormalities were documented in a samoyed male and its five offspring. Haematological abnormalities, found in repeated tests in all the dogs, included marked eosinophilia, eosinophilic bands and absence of Barr bodies. Two of the dogs had bilateral buphthalmia, retinal detachments and other ocular abnormalities. Three of the dogs had skeletal abnormalities including chondrodysplasia (dwarfism) and brachygnathia (undershot jaw). A similar combination of inherited skeletal and ocular disorders, without the haematological abnormalities, has been described in samoyeds. Acquired causes for the haematological findings, which are similar to the inherited Pelger-Huët anomaly described in several species, have been eliminated. Eosinophilic bands and scarcity of Barr bodies could be a marker, or a previously unreported manifestation, of an inherited disorder in samoyeds

Reading the dental record : a dental anthropological approach to foodways, health and disease, and crafting in the pre-Columbian Caribbean

NARCIS (Netherlands)

Mickleburgh, Hayley Louise

2013-01-01

Reading the Dental Record investigates human foodways, health and disease, and certain (gender-related) craft activities in the pre-Columbian Caribbean archipelago, through integrated analyses of patterns of dental wear and pathology in a large number of skeletal remains from the region.

Glucose transporter expression in human skeletal muscle fibers

DEFF Research Database (Denmark)

Gaster, M; Handberg, A; Beck-Nielsen, H

2000-01-01

, but its expression is markedly reduced around birth and is further reduced to undetectable levels within the first year of life; 2) GLUT-3 protein expression appears at 18 wk of gestation and disappears after birth; and 3) GLUT-4 protein is diffusely expressed in muscle cells throughout gestation, whereas...... after birth, the characteristic subcellular localization is as seen in adult muscle fibers. Our results show that GLUT-1, GLUT-3, and GLUT-4 seem to be of importance during muscle fiber growth and development. GLUT-5 protein was undetectable in fetal and adult skeletal muscle fibers. In adult muscle...... amplification (TSA) technique to detect the localization of glucose transporter expression in human skeletal muscle. We found expression of GLUT-1, GLUT-3, and GLUT-4 in developing human muscle fibers showing a distinct expression pattern. 1) GLUT-1 is expressed in human skeletal muscle cells during gestation...

Physiological aspects of the subcellular localization of glycogen in skeletal muscle

DEFF Research Database (Denmark)

Nielsen, Joachim; Ørtenblad, Niels

2013-01-01

Glucose is stored in skeletal muscle fibers as glycogen, a branched-chain polymer observed in electron microscopy images as roughly spherical particles (known as β-particles of 10-45 nm in diameter), which are distributed in distinct localizations within the myofibers and are physically associated...... investigated the role and regulation of these distinct deposits of glycogen. In this report, we review the available literature regarding the subcellular localization of glycogen in skeletal muscle as investigated by electron microscopy studies and put this into perspective in terms of the architectural......, topological, and dynamic organization of skeletal muscle fibers. In summary, the distribution of glycogen within skeletal muscle fibers has been shown to depend on the fiber phenotype, individual training status, short-term immobilization, and exercise and to influence both muscle contractility...

Protein and amino acid metabolism in skeletal muscle

Energy Technology Data Exchange (ETDEWEB)

Wu, Guoyao.

1989-01-01

Isolated chick extensor digitorum communis (EDC) muscles and, in some experiments, rat skeletal muscles were used to study a number of aspects of protein and amino acid metabolism. (1) Chick EDC muscles synthesize and release large amounts of alanine and glutamine, which indirectly obtain their amino groups from branched-chain amino acids (BCAA). (2) Acetoacetate or DL-{beta}-hydroxybutyrate (4 mM) decrease (P < 0.01) alanine synthesis and BCAA transamination in EDC muscles from 24-h fasted chicks by decreasing (P < 0.01) intracellular concentrations of pyruvate due to inhibition of glycolysis. (3) Glutamine is extensively degraded in skeletal muscles from both chicks and rats, thus challenging the traditional view that glutamine oxidation is negligible in skeletal muscle. The cytosolic glutamine aminotransferases L and K in the rat and the mitochondrial phosphate-activated glutaminase in the chick play important roles in the conversion of glutamine to {alpha}-ketoglutarate for further oxidation. (4) Although methionine has been reported to be extensively transaminated in rat skeletal muscle preparations in the absence of other amino acids, transamination of methionine is absent or negligible in chick and rat skeletal muscles in the presence of physiological concentrations of amino acids. (5) Glutamine at 1.0-15 mM increases (P < 0.01) protein synthesis ({sup 3}H-phenylalanine incorporation), and at 10.0-15.0 mM decreases (P < 0.05) protein degradation ({sup 3}H-phenylalanine release from prelabelled protein in vivo) in EDC muscles from fed chicks as compared to muscles incubated in the absence of glutamine. (6) Acetoacetate or DL-{beta}-hydroxybutyrate (4 mM) has a small but significant inhibitory effect (P < 0.05) on the rate of protein synthesis, but has no effect (P > 0.05) on the rate of protein degradation in EDC muscles from fed chicks.

Elevated Cardiac Troponin T in Patients With Skeletal Myopathies.

Science.gov (United States)

Schmid, Johannes; Liesinger, Laura; Birner-Gruenberger, Ruth; Stojakovic, Tatjana; Scharnagl, Hubert; Dieplinger, Benjamin; Asslaber, Martin; Radl, Roman; Beer, Meinrad; Polacin, Malgorzata; Mair, Johannes; Szolar, Dieter; Berghold, Andrea; Quasthoff, Stefan; Binder, Josepha S; Rainer, Peter P

2018-04-10

Cardiac troponins are often elevated in patients with skeletal muscle disease who have no evidence of cardiac disease. The goal of this study was to characterize cardiac troponin concentrations in patients with myopathies and derive insights regarding the source of elevated troponin T measurements. Cardiac troponin T (cTnT) and cardiac troponin I (cTnI) concentrations were determined by using high sensitivity assays in 74 patients with hereditary and acquired skeletal myopathies. Patients underwent comprehensive cardiac evaluation, including 12-lead electrocardiogram, 24-h electrocardiogram, cardiac magnetic resonance imaging, and coronary artery computed tomography. cTnT and cTnI protein expression was determined in skeletal muscle samples of 9 patients and in control tissues derived from autopsy using antibodies that are used in commercial assays. Relevant Western blot bands were subjected to liquid chromatography tandem mass spectrometry for protein identification. Levels of cTnT (median: 24 ng/l; interquartile range: 11 to 54 ng/l) were elevated (>14 ng/l) in 68.9% of patients; cTnI was elevated (>26 ng/l) in 4.1% of patients. Serum cTnT levels significantly correlated with creatine kinase and myoglobin (r = 0.679 and 0.786, respectively; both p < 0.001). Based on cTnT serial testing, 30.1% would have fulfilled current rule-in criteria for myocardial infarction. Noncoronary cardiac disease was present in 23%. Using cTnT antibodies, positive bands were found in both diseased and healthy skeletal muscle at molecular weights approximately 5 kDa below cTnT. Liquid chromatography tandem mass spectrometry identified the presence of skeletal troponin T isoforms in these bands. Measured cTnT concentrations were chronically elevated in the majority of patients with skeletal myopathies, whereas cTnI elevation was rare. Our data indicate that cross-reaction of the cTnT immunoassay with skeletal muscle troponin isoforms was the likely cause. Copyright © 2018 The

Non-surgical Management of Skeletal Class III Malocclusion with Bilateral Posterior Crossbite: A Case Report.

Science.gov (United States)

Kumari, Lalima; Nayan, Kamal

2016-12-01

A 16-year-old female patient with skeletal Class III malocclusion and bilateral posterior cross bite complaining of difficulty in chewing was treated orthodontically without surgery (camouflage treatment). The treatment comprised of fixed orthodontic treatment with MBT prescription (0.022˝×0.028˝ slot) using quad helix appliance for bilateral expansion of maxillary arch and Class III elastics for occlusal correction. Post-treatment records showed normal overbite and overjet with acceptable occlusion. So with this treatment strategy of expanding the maxillary arch using a quad helix appliance and use of Class III elastics, we achieved a good result with optimal occlusion.

A modern documented Italian identified skeletal collection of 2127 skeletons: the CAL Milano Cemetery Skeletal Collection.

Science.gov (United States)

Cattaneo, Cristina; Mazzarelli, Debora; Cappella, Annalisa; Castoldi, Elisa; Mattia, Mirko; Poppa, Pasquale; De Angelis, Danilo; Vitello, Antonio; Biehler-Gomez, Lucie

2018-06-01

The CAL Milano Cemetery Skeletal Collection is a modern and continuously growing identified osteological collection of 2127 skeletons under study in the Laboratorio di Antropologia e Odontologia Forense (LABANOF) in the Department of Biomedical Sciences for Health of the University of Milan (Italy), and part of the Collezione Antropologica LABANOF (CAL). The collection presents individuals of both sexes and of all age groups with a high representation of the elderly and an interesting sample of infants. Each individual is associated with a documentation that includes sex, age-at-death, dates of birth and death, and a death certificate that specifies the exact cause of death and the chain of events that led to it (related pathological conditions or traumatic events). It was also possible to recover for several individuals the autopsy reports and antemortem photographs. This documented osteological collection is of crucial interest in physical and forensic anthropology: it provides unique teaching opportunities and more importantly considerable research possibilities to test and develop sex and age estimation methods, investigate key subjects of forensic relevance and discuss pathological markers, among others. The aim of this paper is to introduce the CAL Milano Cemetery Skeletal Collection as a new identified skeletal collection and present its research and teaching potential. Copyright © 2018 Elsevier B.V. All rights reserved.

Biosynthetic effects on the stable carbon isotopic compositions of agal lipids: Implications for deciphering the carbon isotopic biomarker record

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Schouten, S.; Klein Breteler, W.C.M.; Blokker, P.; Schogt, N.; Rijpstra, W.I.C.; Grice, K.; Baas, M.

1998-01-01

Thirteen species of algae covering an extensive range of classes were cultured and stable carbon isotopic compositions of their lipids were analysed in order to assess carbon isotopic fractionation effects during their biosynthesis. The fatty acids were found to have similar stable carbon isotopic

Selenium regulates gene expression of selenoprotein W in chicken skeletal muscle system.

Science.gov (United States)

Ruan, Hongfeng; Zhang, Ziwei; Wu, Qiong; Yao, Haidong; Li, Jinlong; Li, Shu; Xu, Shiwen

2012-01-01

Selenoprotein W (SelW) is abundantly expressed in skeletal muscles of mammals and necessary for the metabolism of skeletal muscles. However, its expression pattern in skeletal muscle system of birds is still uncovered. Herein, to investigate the distribution of SelW mRNA in chicken skeletal muscle system and its response to different selenium (Se) status, 1-day-old chickens were exposed to various concentrations of Se as sodium selenite in the feed for 35 days. In addition, myoblasts were treated with different concentrations of Se in the medium for 72 h. Then the levels of SelW mRNA in skeletal muscles (wing muscle, pectoral muscle, thigh muscle) and myoblasts were determined on days 1, 15, 25, and 35 and at 0, 24, 48, and 72 h, respectively. The results showed that SelW was detected in all these muscle components and it increased both along with the growth of organism and the differentiation process of myoblasts. The thigh muscle is more responsive to Se intake than the other two skeletal muscle tissues while the optimal Se supplementation for SelW mRNA expression in chicken myoblasts was 10(-7) M. In summary, Se plays important roles in the development of chicken skeletal muscles. To effect optimal SelW gene expression, Se must be provided in the diet and the media in adequate amounts and neither at excessive nor deficient levels.

Regulation of PDH, GS and insulin signalling in skeletal muscle

DEFF Research Database (Denmark)

Biensø, Rasmus Sjørup

of inflammation on resting and exercise-induced PDH regulation in human skeletal muscle and 4) The effect of IL-6 on PDH regulation in mouse skeletal muscle. Study I demonstrated that bed rest–induced insulin resistance was associated with reduced insulinstimulated GS activity and Akt signaling as well...

Radiology of skeletal and soft tissue changes

International Nuclear Information System (INIS)

Walker, H.C. Jr.; Coleman, C.C.; Hunter, D.W.

1986-01-01

Skeletal complications are very common in renal transplant patients. Loss of bone mass in the posttransplant period places the skeletal system in jeopardy. Osteonecrosis, while not life threatening, often prevents rehabilitation. Spontaneous fractures are frequent but are usually not a major problem except in the diabetic transplant recipient. Septic arthritis and osteomyelitis are usually successfully managed by conservative measures, except when accompanied by severe occlusive vascular disease. Juvenile onset diabetic patients still may develop disabling neuropathic joint disease or occlusive vascular disease after renal transplantation. The authors hope that successful pancreas transplantation will avert these problems in the future

A 200 year sedimentary record of progressive eutrophication in lake Greifen (Switzerland): Implications for the origin of organic-carbon-rich sediments

Science.gov (United States)

Hollander, David J.; McKenzie, Judith A.; Lo Ten Haven, H.

1992-09-01

Over the past 200 years Lake Greifen, a small lake in northeastern Switzerland, has undergone dramatic changes in primary productivity and eutrophication due to increased nutrient supply from agricultural activity and industrialization. A 40 year historical record of the water-column chemistry indicates that productivity and eutrophication reached a maximum in 1974, after which stricter regulations on the input of nutrients resulted in a progressive decrease. Collected cores show the sedimentary expression of this anthropogenically induced eutrophication by a well-developed annual sedimentation and by enhanced values of total organic carbon, organic-carbon accumulation rates, and hydrogen indices (HI) of the kerogens. Analyses of the carbon isotopic composition of sedimentary carbonates and organic matter reveal that the fractionation between these two phases varies with the HI of kerogens. This observation is explicable in terms of changing productivity and preservation of the organic matter, and the CO2(aq) budget of the water body. We propose that if high primary productivity were primarily responsible for the preservation and accumulation of organic matter, then a negative correlation will occur between Δδ13Ccalcite-organic matter (Δδ13Ccal-om) and HI values. In an environment with relatively low to moderate productivity but with bottom-water anoxia, a positive correlation will exist between Δδ13Ccal-om and HI values. This study of Lake Greifen has implications for understanding paleoenvironmental controls on ancient organic-carbon-rich sediments.

Chiral Orientation of Skeletal Muscle Cells Requires Rigid Substrate

Directory of Open Access Journals (Sweden)

Ninghao Zhu

2017-06-01

Full Text Available Reconstitution of tissue morphology with inherent left–right (LR asymmetry is essential for tissue/organ functions. For skeletal muscle, the largest tissue in mammalian organisms, successful myogenesis requires the regulation of the LR asymmetry to form the appropriate muscle alignment. However, the key factor for reproducing the LR asymmetry of skeletal tissues in a controllable, engineering context remains largely unknown. Recent reports indicate that cell chirality may underlie the LR development in tissue morphogenesis. Here, we report that a rigid substrate is required for the chirality of skeletal muscle cells. By using alternating micropatterned cell-adherent and cell-repellent stripes on a rigid substrate, we found that C2C12 skeletal muscle myoblasts exhibited a unidirectional tilted orientation with respect to the stripe boundary. Importantly, such chiral orientation was reduced when soft substrates were used instead. In addition, we demonstrated the key role of actin stress fibers in the formation of the chiral orientation. This study reveals that a rigid substrate is required for the chiral pattern of myoblasts, paving the way for reconstructing damaged muscle tissue with inherent LR asymmetry in the future.

Alterations of cAMP-dependent signaling in dystrophic skeletal muscle

Directory of Open Access Journals (Sweden)

Rüdiger eRudolf

2013-10-01

Full Text Available Autonomic regulation processes in striated muscles are largely mediated by cAMP/PKA-signaling. In order to achieve specificity of signaling its spatial-temporal compartmentation plays a critical role. We discuss here how specificity of cAMP/PKA-signaling can be achieved in skeletal muscle by spatio-temporal compartmentation. While a microdomain containing PKA type I in the region of the neuromuscular junction is important for post-synaptic, activity-dependent stabilization of the nicotinic acetylcholine receptor, PKA type I and II microdomains in the sarcomeric part of skeletal muscle are likely to play different roles, including the regulation of muscle homeostasis. These microdomains are due to specific A-kinase anchoring proteins, like rapsyn and myospryn. Importantly, recent evidence indicates that compartmentation of the cAMP/PKA-dependent signaling pathway and pharmacological activation of cAMP production are aberrant in different skeletal muscles disorders. Thus, we discuss here their potential as targets for palliative treatment of certain forms of dystrophy and myasthenia. Under physiological conditions, the neuropeptide, α-calcitonin-related peptide, as well as beta-adrenergic agonists are the most-mentioned natural triggers for activating cAMP/PKA signaling in skeletal muscle. While the precise domains and functions of these first messengers are still under investigation, agonists of β2-adrenoceptors clearly exhibit anabolic activity under normal conditions and reduce protein degradation during atrophic periods. Past and recent studies suggest direct sympathetic innervation of skeletal muscle fibers. In summary, the organization and roles of cAMP-dependent signaling in skeletal muscle are increasingly understood, revealing crucial functions in processes like nerve-muscle interaction and muscle trophicity.

X-ray image intensifier/television systems for digital skeletal radiography

International Nuclear Information System (INIS)

Rowlands, J.A.; Hynes, D.M.; Edmonds, E.W.; Porter, A.J.; Toth, B.J.

1987-01-01

The imaging criteria for skeletal radiography (high resolution and low noise) relevant to the use of x-ray image intensifier/TV digital systems are discussed. It is shown from the modulation transfer function (MTF), noise, and phantom evaluations that conventional x-ray image intensifiers in conjunction with a 1,000-line Plumbicon or Saticon TV camera are in most respects suitable for skeletal radiography. The optimum focal spot size depends on a trade-off with motion blurring through the x-ray exposure time and so is a function of the clinical problem. Since the skeletal system is readily immobilized, a 0.3-mm focal spot size is nearly optimum

Skeletal metastases in pancreatic carcinoma: study by isotopic bone scanning

Energy Technology Data Exchange (ETDEWEB)

Hatfield, D R; Deland, F H; Maruyama, Y

1976-01-01

A review of the literature of 2,155 reported patients with primary carcinoma of the pancreas, revealed 110 cases or 5 percent to have skeletal metastasis by radiographic or autopsy study. A study conducted over a 2 year period disclosed that 1 case of skeletal metastasis was detected by bone scanning in 16 patients with pancreatic carcinoma. This indicates a minimum skeletal metastasis rate of 6 percent. We feel these percentages are low and can be further defined by the more routine employment of the bone scan to evaluate patients with carcinoma of the pancreas. The true figure may be much higher, perhaps as high as 20 percent.

Bomb-test 90Sr in Pacific and Indian Ocean surface water as recorded by banded corals

International Nuclear Information System (INIS)

Toggweiler, J.R.; Trumbore, S.

1985-01-01

We report here measurements of bomb-test 90 Sr activity in the CaCO 3 skeletons of banded head forming corals collected from nine locations in the tropical Pacific and Indian Oceans. Density variations in skeletal carbonate demarcate annual growth bands and allow one to section individual years. Measurements of 90 Sr activity in the annual bands reconstruct the activity of the water in which the coral grew. Our oldest records date to the early years of the nuclear era and record not only fallout deposition from the major U.S. and Soviet tests of 1958-1962, but also the huge, and largely unappreciated, localized inputs from the U.S. tests at Eniwetok and Bikini atolls during 1952-1958. In the 1960's the 90 Sr activity in Indian Ocean surface water was twice as high as activity levels in the South Pacific at comparable latitudes. We suggest that substantial amounts of northern hemisphere fallout moved west and south into the Indian Ocean via passages through the Indonesian archipelago. Equatorial Pacific 90 Sr levels have remained relatively constant from the mid 1960's through the end of 1970's in spite of 90 Sr decay, reflecting a large-scale transfer of water between the temperate and tropical North Pacific. Activity levels at Fanning Is. (4 0 N, 160 0 W) appear to vary in conjunction with the 3-4 year El Nino cycle. (orig.)

L-Citrulline Supplementation-Increased Skeletal Muscle PGC-1α Expression is Associated With Exercise Performance and Increased Skeletal Muscle Weight.

Science.gov (United States)

Villareal, Myra O; Matsukawa, Toshiya; Isoda, Hiroko

2018-05-24

L-citrulline has recently been reported as a more effective supplement for promoting intracellular NO production compared to L-arginine. Here, the effect of L-citrulline on skeletal muscle and its influence on exercise performance were investigated. The underlying mechanism of its effect, specifically on the expression of skeletal muscle peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α), was also elucidated. Six-week-old ICR mice were orally supplemented with L-citrulline (250 mg kg -1 ) daily, and their performance in weight-loaded swimming exercise every other day for 15 days, was evaluated. In addition, mice muscles were weighed and evaluated for the expression of PGC-1α and PGC-1α-regulated genes. Mice orally supplemented with L-citrulline had significantly higher gastrocnemius and biceps femoris muscle mass. Although not statistically significant, L-citrulline prolonged the swimming time to exhaustion. PGC-1α upregulation was associated with vascular endothelial growth factor α (VEGFα) and insulin-like growth factor 1 (IGF1) upregulation. VEGFα and IGF1 are important for angiogenesis and muscle growth, respectively, and are regulated by PGC-1α. Treatment with L-NAME, a nitric oxide synthesis inhibitor, suppressed the L-citrulline-induced PGC-1α upregulation in-vitro. Supplementation with L-citrulline upregulates skeletal muscle PGC-1α levels resulting to higher skeletal muscle weight that improves time to exhaustion during exercise. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Ossified skeletal muscle hemangioma: Radiologic and pathologic features

Energy Technology Data Exchange (ETDEWEB)

Engelstad, B L; Gilula, L A [Mallinckrodt Inst. of Radiology, St. Louis, MO (USA); Kynakos, M [Washington Univ., St. Louis, MO (USA). Dept. of Surgical Pathology

1980-01-01

Skeletal muscle hemangiomas are relatively uncommon tumors in children and young adults. Although the operative management of these lesions may be affected by their vascularity, the correct preoperative diagnosis is often not made. Ossification of these lesions is rare. Two patients are described whose skeletal muscle hemangiomas contained abundant osseous tissue. This was radiologically reflected by the 'swiss cheese' appearance of the tumors. Such an appearance in an ossified soft tissue mass may allow the correct preoperative diagnosis of this condition.

Radiological contribution to skeletal changes in systemic mastocytosis - urticaria pigmentosa

Energy Technology Data Exchange (ETDEWEB)

Schratter, M.; Canigiani, G.; Schoenbauer, C.; Mach, K.

1983-11-01

Three patients are demonstrated suffering from systemic mastocytosis with skin and skeletal involvement. History, clinical and radiological results are reported. After a brief analysis of the pathogenetic mechanism, the radiological findings on the skeletal system in systemic mastocytosis are discussed. Finally, roentgenological differential diagnosis of the osseous lesions is explained.

Global Carbon Cycle of the Precambrian Earth

DEFF Research Database (Denmark)

Wiewióra, Justyna

The carbon isotopic composition of distinct Archaean geological records provides information about the global carbon cycle and emergence of life on early Earth. We utilized carbon isotopic records of Greenlandic carbonatites, diamonds, graphites, marbles, metacarbonates and ultramafic rocks...... in the surface environment and recycled back into the mantle In the third manuscript we investigate the carbon cycle components, which have maintained the carbon isotope composition of the mantle constant through time. Assuming constant organic ratio of the total carbon burial (f), we show that increased.......1‰) and metacarbonate ( -6.1 ± 0.1‰ to +1.5 ± 0.0‰) rocks from the ~3.8 Ga Isua Supracrustal Belt as resulting from the Rayleigh distillation process, which affected the ultramafic reservoir with initial δ13C between -2‰ and 0‰. Due to its high primary δ13C signature, carbon in the Isuan magnesite was most likely...

Ammonia lowering reverses sarcopenia of cirrhosis by restoring skeletal muscle proteostasis.

Science.gov (United States)

Kumar, Avinash; Davuluri, Gangarao; Silva, Rafaella Nascimento E; Engelen, Marielle P K J; Ten Have, Gabrie A M; Prayson, Richard; Deutz, Nicolaas E P; Dasarathy, Srinivasan

2017-06-01

Sarcopenia or skeletal muscle loss is a frequent, potentially reversible complication in cirrhosis that adversely affects clinical outcomes. Hyperammonemia is a consistent abnormality in cirrhosis that results in impaired skeletal muscle protein synthesis and breakdown (proteostasis). Despite the availability of effective ammonia-lowering therapies, whether lowering ammonia restores proteostasis and increases muscle mass is unknown. Myotube diameter, protein synthesis, and molecular responses in C2C12 murine myotubes to withdrawal of ammonium acetate following 24-hour exposure to 10 mM ammonium acetate were complemented by in vivo studies in the hyperammonemic portacaval anastomosis rat and sham-operated, pair-fed Sprague-Dawley rats treated with ammonia-lowering therapy by l-ornithine l-aspartate and rifaximin orally for 4 weeks. We observed reduced myotube diameter, impaired protein synthesis, and increased autophagy flux in response to hyperammonemia, which were partially reversed following 24-hour and 48-hour withdrawal of ammonium acetate. Consistently, 4 weeks of ammonia-lowering therapy resulted in significant lowering of blood and skeletal muscle ammonia, increase in lean body mass, improved grip strength, higher skeletal muscle mass and diameter, and an increase in type 2 fibers in treated compared to untreated portacaval anastomosis rats. The increased skeletal muscle myostatin expression, reduced mammalian target of rapamycin complex 1 function, and hyperammonemic stress response including autophagy markers normally found in portacaval anastomosis rats were reversed by treatment with ammonia-lowering therapy. Despite significant improvement, molecular and functional readouts were not completely reversed by ammonia-lowering measures. Ammonia-lowering therapy results in improvement in skeletal muscle phenotype and function and molecular perturbations of hyperammonemia; these preclinical studies complement previous studies on ammonia-induced skeletal muscle

Evaluation of cervical posture of children in skeletal class I, II, and III.

Science.gov (United States)

D'Attilio, Michele; Caputi, Sergio; Epifania, Ettore; Festa, Felice; Tecco, Simona

2005-07-01

Previous studies on the relationship between morphological structure of the face and cervical posture have predominantly focused on vertical dimensions of the face. The aim of this study was to investigate whether there are significant differences in cervical posture in subjects with a different sagittal morphology of the face, i.e., a different skeletal class. One hundred twenty (120) children (60 males and 60 females, average age 9.5 yrs., SD+/-0.5) were admitted for orthodontic treatment. Selection criteria was: European ethnic origin, date of birth, considerable skeletal growth potential remaining and an absence of temporomandibular joint dysfunction (TMD). Lateral skull radiographs were taken in mirror position. Subjects were divided into three groups based on their skeletal class. The cephalometric tracings included postural variables. The most interesting findings were: 1. children in skeletal class III showed a significantly lower cervical lordosis angle (phead upon the spinal column compared to children in skeletal class I and skeletal class III (pposture of the neck seems to be strongly associated with the sagittal as well as the vertical structure of the face.

Skeletal muscle metastases of carcinoma. A clinicopathological study of 12 cases

International Nuclear Information System (INIS)

Tuoheti, Y.; Okada, Kyoji; Hashimoto, Manabu; Itoi, Eiji

2004-01-01

The objective of this study was to clarify the clinical and magnetic resonance (MR) imaging features of a rare condition of metastasis of carcinoma to skeletal muscle. Clinicopathological findings for 12 patients (10 male, two female, age range 48-89 years, mean age 68 years) with skeletal muscle metastases of carcinomas were reviewed retrospectively. In nine of the 12 patients the skeletal muscle metastasis was presented as 'painful mass'. The lung was found to be the most common primary source, accounting for 33% of the cases, and the lower extremity was the most common metastatic site, accounting for 67% of the current series. Diagnosis was made by biopsy in all cases. Overall, MR images were not specific, but on the gadolinium-DTPA enhanced MR images, extensive peritumoral enhancement associated with central necrosis was found in 11 of the 12 patients (92%). Seven patients died within 2-19 months (average: 9 months) after the detection of the skeletal muscle metastasis, among whom only one patient was continuously disease free for 92 months after wide excision of the metastatic lesion. Skeletal muscle metastasis is often presented as a painful mass in patients with known primary carcinoma. For diagnosis, needle biopsy is mandatory. However, a painful mass with an extensive peritumoral enhancement should be highly suspected to represent carcinoma metastasis to skeletal muscles. In selected patients, wide excision with combined chemotherapy could yield unexpectedly good results. (author)

Quantitative sonoelastography for the in vivo assessment of skeletal muscle viscoelasticity

International Nuclear Information System (INIS)

Hoyt, Kenneth; Kneezel, Timothy; Castaneda, Benjamin; Parker, Kevin J

2008-01-01

A novel quantitative sonoelastography technique for assessing the viscoelastic properties of skeletal muscle tissue was developed. Slowly propagating shear wave interference patterns (termed crawling waves) were generated using a two-source configuration vibrating normal to the surface. Theoretical models predict crawling wave displacement fields, which were validated through phantom studies. In experiments, a viscoelastic model was fit to dispersive shear wave speed sonoelastographic data using nonlinear least-squares techniques to determine frequency-independent shear modulus and viscosity estimates. Shear modulus estimates derived using the viscoelastic model were in agreement with that obtained by mechanical testing on phantom samples. Preliminary sonoelastographic data acquired in healthy human skeletal muscles confirm that high-quality quantitative elasticity data can be acquired in vivo. Studies on relaxed muscle indicate discernible differences in both shear modulus and viscosity estimates between different skeletal muscle groups. Investigations into the dynamic viscoelastic properties of (healthy) human skeletal muscles revealed that voluntarily contracted muscles exhibit considerable increases in both shear modulus and viscosity estimates as compared to the relaxed state. Overall, preliminary results are encouraging and quantitative sonoelastography may prove clinically feasible for in vivo characterization of the dynamic viscoelastic properties of human skeletal muscle

Role of MCT1 and CAII in skeletal muscle pH homeostasis, energetics, and function: in vivo insights from MCT1 haploinsufficient mice

KAUST Repository

Chatel, Benjamin; Bendahan, David; Hourdé , Christophe; Pellerin, Luc; Lengacher, Sylvain; Magistretti, Pierre J.; Le Fur, Yann; Vilmen, Christophe; Bernard, Monique; Messonnier, Laurent A.

2017-01-01

The purpose of this study was to investigate the effects of a partial suppression of monocarboxylate transporter (MCT)-1 on skeletal muscle pH, energetics, and function (MCT1(+/-) mice). Twenty-four MCT1(+/-) and 13 wild-type (WT) mice were subjected to a rest-exercise-recovery protocol, allowing assessment of muscle energetics (by magnetic resonance spectroscopy) and function. The study included analysis of enzyme activities and content of protein involved in pH regulation. Skeletal muscle of MCT1(+/-) mice had lower MCT1 (-61%; P < 0.05) and carbonic anhydrase (CA)-II (-54%; P < 0.05) contents. Although intramuscular pH was higher in MCT1(+/-) mice at rest (P < 0.001), the mice showed higher acidosis during the first minute of exercise (P < 0.01). Then, the pH time course was similar among groups until exercise completion. MCT1(+/-) mice had higher specific peak (P < 0.05) and maximum tetanic (P < 0.01) forces and lower fatigability (P < 0.001) when compared to WT mice. We conclude that both MCT1 and CAII are involved in the homeostatic control of pH in skeletal muscle, both at rest and at the onset of exercise. The improved muscle function and resistance to fatigue in MCT1(+/-) mice remain unexplained.-Chatel, B., Bendahan, D., Hourdé, C., Pellerin, L., Lengacher, S., Magistretti, P., Fur, Y. L., Vilmen, C., Bernard, M., Messonnier, L. A. Role of MCT1 and CAII in skeletal muscle pH homeostasis, energetics, and function: in vivo insights from MCT1 haploinsufficient mice.

Role of MCT1 and CAII in skeletal muscle pH homeostasis, energetics, and function: in vivo insights from MCT1 haploinsufficient mice

KAUST Repository

Chatel, Benjamin

2017-03-03

The purpose of this study was to investigate the effects of a partial suppression of monocarboxylate transporter (MCT)-1 on skeletal muscle pH, energetics, and function (MCT1(+/-) mice). Twenty-four MCT1(+/-) and 13 wild-type (WT) mice were subjected to a rest-exercise-recovery protocol, allowing assessment of muscle energetics (by magnetic resonance spectroscopy) and function. The study included analysis of enzyme activities and content of protein involved in pH regulation. Skeletal muscle of MCT1(+/-) mice had lower MCT1 (-61%; P < 0.05) and carbonic anhydrase (CA)-II (-54%; P < 0.05) contents. Although intramuscular pH was higher in MCT1(+/-) mice at rest (P < 0.001), the mice showed higher acidosis during the first minute of exercise (P < 0.01). Then, the pH time course was similar among groups until exercise completion. MCT1(+/-) mice had higher specific peak (P < 0.05) and maximum tetanic (P < 0.01) forces and lower fatigability (P < 0.001) when compared to WT mice. We conclude that both MCT1 and CAII are involved in the homeostatic control of pH in skeletal muscle, both at rest and at the onset of exercise. The improved muscle function and resistance to fatigue in MCT1(+/-) mice remain unexplained.-Chatel, B., Bendahan, D., Hourdé, C., Pellerin, L., Lengacher, S., Magistretti, P., Fur, Y. L., Vilmen, C., Bernard, M., Messonnier, L. A. Role of MCT1 and CAII in skeletal muscle pH homeostasis, energetics, and function: in vivo insights from MCT1 haploinsufficient mice.

Glucocorticoids and inhibition of bone formation induced by skeletal unloading

International Nuclear Information System (INIS)

Halloran, B.P.; Bikle, D.D.; Cone, C.M.; Morey-Holton, E.

1988-01-01

Skeletal unloading or loss of normal weight bearing in the growing animal inhibits bone formation and reduces bone calcium. To determine whether the inhibition of bone formation induced by skeletal unloading is a consequence of an increase in plasma glucocorticoids and/or an increase in bone sensitivity to glucocorticoids, the authors measured plasma corticosterone throughout the day in unloaded and normally loaded rats (hindlimb elevation model) and examined the effect of adrenalectomy on the response of bone to skeletal unloading. Plasma corticosterone levels were similar in normally loaded and unloaded rats at all times. Skeletal unloading in sham-adrenalectomized animals reduced tibial and vertebral calcium by 11.5 and 11.1%, respectively, and in adrenalectomized animals by 15.3 and 20.3%, respectively. Uptake of 45 Ca and [ 3 H]proline in the tibia was reduced by 8 and 14%, respectively, in the sham-adrenalectomized animals and by 13 and 19% in the adrenalectomized animals. Bone formation and apposition rates were reduced to the same level in sham- and adrenalectomized animals. These results suggest that the inhibition of bone formation induced by skeletal unloading is not a consequence of increased plasma glucocorticoids or an increase in bone sensitivity to the glucocorticoids but, rather, point to a local mediator in bone that senses mechanical load and transmits that information to the bone-forming cells directly

 Age-related changes of skeletal muscles: physiology, pathology and regeneration

Directory of Open Access Journals (Sweden)

Aleksandra Ławniczak

2012-06-01

Full Text Available  This review provides a short presentation of the aging-related changes of human skeletal muscles. The aging process is associated with the loss of skeletal muscle mass (sarcopenia and strength. This results from fibre atrophy and apoptosis, decreased regeneration capacity, mitochondrial dysfunction, gradual reduction of the number of spinal cord motor neurons, and local and systemic metabolic and hormonal alterations. The latter involve age-related decrease of the expression and activity of some mitochondrial and cytoplasmic enzymes, triacylglycerols and lipofuscin accumulation inside muscle fibres, increased proteolytic activity, insulin resistance and decreased serum growth hormone and IGF-1 concentrations. Aging of the skeletal muscles is also associated with a decreased number of satellite cells and their proliferative activity. The age-related reduction of skeletal muscle mass and function may be partially prevented by dietary restriction and systematic physical exercises.

Unusual skeletal metastases from myxoid liposarcoma only detectable by MR imaging

International Nuclear Information System (INIS)

Ishii, T.; Ueda, T.; Myoui, A.; Tamai, N.; Hosono, N.; Yoshikawa, H.

2003-01-01

We present two cases of skeletal metastases from myxoid liposarcoma, occurring several years after treatment of the primary tumors in the lower limb. The present two case reports have unusual radiological features only detectable by MR imaging and not by plain radiographs or bone scans. From the present two cases, we found that a negative plain radiograph of the spine or a negative bone scan could not exclude skeletal metastases from myxoid liposarcoma, and MRI was a more sensitive screening procedure for their detection, especially in T1-weighted images. Unusual radiological features of skeletal metastases from myxoid liposarcoma are not well documented and only a few cases have been previously reported. Our aim is to document two more patients exhibiting the unusual radiological features of skeletal metastases from myxoid liposarcoma to improve their early detection and management. (orig.)

Akt1 deficiency diminishes skeletal muscle hypertrophy by reducing satellite cell proliferation.

Science.gov (United States)

Moriya, Nobuki; Miyazaki, Mitsunori

2018-02-14

Skeletal muscle mass is determined by the net dynamic balance between protein synthesis and degradation. Although the Akt/mechanistic target of rapamycin (mTOR)-dependent pathway plays an important role in promoting protein synthesis and subsequent skeletal muscle hypertrophy, the precise molecular regulation of mTOR activity by the upstream protein kinase Akt is largely unknown. In addition, the activation of satellite cells has been indicated as a key regulator of muscle mass. However, the requirement of satellite cells for load-induced skeletal muscle hypertrophy is still under intense debate. In this study, female germline Akt1 knockout (KO) mice were used to examine whether Akt1 deficiency attenuates load-induced skeletal muscle hypertrophy through suppressing mTOR-dependent signaling and satellite cell proliferation. Akt1 KO mice showed a blunted hypertrophic response of skeletal muscle, with a diminished rate of satellite cell proliferation following mechanical overload. In contrast, Akt1 deficiency did not affect the load-induced activation of mTOR signaling and the subsequent enhanced rate of protein synthesis in skeletal muscle. These observations suggest that the load-induced activation of mTOR signaling occurs independently of Akt1 regulation and that Akt1 plays a critical role in regulating satellite cell proliferation during load-induced muscle hypertrophy.

Radiation injury to skeletal muscle

International Nuclear Information System (INIS)

Persons, C.C.M.; Wondergem, J.; Leer, J.W.H.

1997-01-01

Radiotherapy of neoplasia has increased the mean life expectancy of cancer patients. On the other hand, more reports are published on morbidity of the treatment with regard to normal tissue. Studies on skeletal muscle injury specifically are scarce, but many clinical long term follow-up studies make note of side effects as muscle atrophy, fibrosis and limited function. Furthermore it is suggested that skeletal muscles of children are more prone to radiation injury than those of adult subjects. Effects of radiation on skeletal muscle were studied in rats. On hind limb of young (100 g) and adult (350 g) rats was irradiated with single doses (15-30 Gy), while the other served as control. Follow-up was up to 12 months post treatment. Muscular function in young rats was decreased significantly at 6 months post irradiation, but did not further decrease in the following 6 months. The amount of collagen, on the other hand, was not increased at 6 months, but became highly elevated at 12 months past treatment. This suggests that at 6 months, impaired muscular function may not be explained by increased fibrotic tissues. This is an agreement with results obtained in adult rats, where function was also impaired, without concomitant increase in collagen. In an earlier study, mitochondrial oxygen consumption was dose dependently decreased after irradiation, at 12 months, but not at 6 months post treatment. Furthermore, myosin-actin interaction was measured in skinned fibers. The first results of this study indicate changes in the interaction of contraction proteins, as early as 6 months post treatment. (authors)

Musculo-Skeletal Abnormalities in Patients with Marfan Syndrome

Directory of Open Access Journals (Sweden)

Ali Al Kaissi

2013-01-01

Full Text Available Background A leptosomic body type is tall and thin with long hands. Marfanoid features may be familial in nature or pathological, as occurs in congenital contractual arachnodactyly (Beal's syndrome and Shprintzen-Goldberg syndrome mimicking some of the changes of Marfan syndrome, although not accompanied by luxation of lens and dissecting aneurysm of aorta. Methods In this article we collected eight patients who were consistent with the diagnosis of Marfan syndrome via phenotypic and genotypic characterization. Results Our patients manifested a constellation of variable presentations of musculo-skeletal abnormalities ranging from developmental dysplasia of the hip, protrusio acetabuli, leg length inequality, patellar instability, scoliosis, to early onset osteoarthritis. Each abnormality has been treated accordingly. Conclusion This is the first paper which includes the diagnosis and the management of the associated musculo-skeletal abnormalities in patients with Marfan syndrome, stressing that patients with Marfan syndrome are exhibiting great variability in the natural history and the severity of musculo-skeletal abnormalities.

Signalling and the control of skeletal muscle size

International Nuclear Information System (INIS)

Otto, Anthony; Patel, Ketan

2010-01-01

Skeletal muscle is highly adaptive to environmental stimuli and can alter its mass accordingly. This tissue is almost unique in that it can increase its size through two distinct mechanisms. It can grow through a cellular process mediated by cell fusion, or it can increase its size simply by increasing its protein content. Understanding how these processes are regulated is crucial for the development of potential therapies against debilitating skeletal muscle wasting diseases. Two key signalling molecules, Insulin like Growth Factor (IGF) and GDF-8/myostatin, have emerged in recent years to be potent regulators of skeletal muscle size. In this review we bring together recent data highlighting the important and novel aspects of both molecules and their signalling pathways, culminating in a discussion of the cellular and tissue phenotypic outcomes of their stimulation or antagonism. We emphasise the complex regulatory mechanisms and discuss the temporal and spatial differences that control their action, understanding of which is crucial to further their use as potential therapeutic targets.

Skeletal recurrences and metastases of extraskeletal myxoid chondrosarcoma

International Nuclear Information System (INIS)

Ehara, Shigeru; Nishida, Jun; Shiraishi, Hideo; Yoshioka, Hiroshi; Okada, Kyoji; Sumiya, Hisashi; Takano, Hideyuki

2007-01-01

The objective was to elucidate clinical and imaging features of skeletal involvement, recurrences, and metastases of extraskeletal myxoid chondrosarcoma. Included in this series are 4 patients, aged 44 to 65 years, 3 of whom were men and 1 a woman. The primary lesions were in the thigh (n 3) and the upper arm (n = 1). Three patients with multiple metastases died of the disease, 2 were considered to have local recurrence in the adjacent bone. Skeletal metastases occurred after lung metastases in 2 cases, and before lung metastases in 1 case. Typical imaging findings are well-defined lesions with no sclerotic margin or matrix mineralization. A slow, but persistent growth is noted on the imaging features. Although skeletal metastases of chondrosarcoma of bone and soft tissue are rare, myxoid chondrosarcomas, currently classified tumors of uncertain differentiation, rarely metastasize and/or recur in the bones. The imaging features are typically of a localized lesion with cortical disruption or expansion. (orig.)

Skeletal recurrences and metastases of extraskeletal myxoid chondrosarcoma

Energy Technology Data Exchange (ETDEWEB)

Ehara, Shigeru [Iwate Medical University School of Medicine, Department of Radiology, Morioka (Japan); Nishida, Jun; Shiraishi, Hideo [Iwate Medical University School of Medicine, Department of Orthopedic Surgery, Iwate (Japan); Yoshioka, Hiroshi [University of Tsukuba School of Medicine, Department of Radiology, Tsukuba (Japan); Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States); Okada, Kyoji [Akita University School of Medicine, Department of Orthopedic Surgery, Akita (Japan); Sumiya, Hisashi [Kanazawa University School of Medicine, Department of Nuclear Medicine, Kanazawa (Japan); Yawata Medical Center, Komatsu (Japan); Takano, Hideyuki [Chiba Cancer Center, Division of Diagnostic Imaging, Chiba (Japan)

2007-09-15

The objective was to elucidate clinical and imaging features of skeletal involvement, recurrences, and metastases of extraskeletal myxoid chondrosarcoma. Included in this series are 4 patients, aged 44 to 65 years, 3 of whom were men and 1 a woman. The primary lesions were in the thigh (n = 3) and the upper arm (n = 1). Three patients with multiple metastases died of the disease, 2 were considered to have local recurrence in the adjacent bone. Skeletal metastases occurred after lung metastases in 2 cases, and before lung metastases in 1 case. Typical imaging findings are well-defined lesions with no sclerotic margin or matrix mineralization. A slow, but persistent growth is noted on the imaging features. Although skeletal metastases of chondrosarcoma of bone and soft tissue are rare, myxoid chondrosarcomas, currently classified tumors of uncertain differentiation, rarely metastasize and/or recur in the bones. The imaging features are typically of a localized lesion with cortical disruption or expansion. (orig.)

Signalling and the control of skeletal muscle size

Energy Technology Data Exchange (ETDEWEB)

Otto, Anthony [School of Biological Sciences, Hopkins Building, University of Reading, Whiteknights Campus, Reading, Berkshire, RG6 6UB (United Kingdom); Patel, Ketan, E-mail: ketan.patel@reading.ac.uk [School of Biological Sciences, Hopkins Building, University of Reading, Whiteknights Campus, Reading, Berkshire, RG6 6UB (United Kingdom)

2010-11-01

Skeletal muscle is highly adaptive to environmental stimuli and can alter its mass accordingly. This tissue is almost unique in that it can increase its size through two distinct mechanisms. It can grow through a cellular process mediated by cell fusion, or it can increase its size simply by increasing its protein content. Understanding how these processes are regulated is crucial for the development of potential therapies against debilitating skeletal muscle wasting diseases. Two key signalling molecules, Insulin like Growth Factor (IGF) and GDF-8/myostatin, have emerged in recent years to be potent regulators of skeletal muscle size. In this review we bring together recent data highlighting the important and novel aspects of both molecules and their signalling pathways, culminating in a discussion of the cellular and tissue phenotypic outcomes of their stimulation or antagonism. We emphasise the complex regulatory mechanisms and discuss the temporal and spatial differences that control their action, understanding of which is crucial to further their use as potential therapeutic targets.

Radiation induced skeletal changes in beagle: dose rates, dose, and age effect analysis from 226Ra

International Nuclear Information System (INIS)

Momeni, M.H.; Williams, J.R.; Rosenblatt, L.S.

1976-01-01

Radiation-induced skeletal injury (E) and the rate of skeletal injury were studied as a function of time and dose in beagles administered 226 Ra Cl 2 in eight semimonthly iv injections starting at 2, 4, or 14 months of age. Skeletal changes were evaluated with a radiographic x-ray scoring system in 20 skeletal regions; each region was scored on a 0 to 6 scale. Bone changes in six regions of humeri were qualitatively analyzed for comparison with total skeletal changes. Skeletal changes were classified by endosteal or periosteal cortical sclerosis and thickening, fractures, osteolytic lesions, and trabecular coarsening

Cartilage and bone cells do not participate in skeletal regeneration in Ambystoma mexicanum limbs.

Science.gov (United States)

McCusker, Catherine D; Diaz-Castillo, Carlos; Sosnik, Julian; Q Phan, Anne; Gardiner, David M

2016-08-01

The Mexican Axolotl is one of the few tetrapod species that is capable of regenerating complete skeletal elements in injured adult limbs. Whether the skeleton (bone and cartilage) plays a role in the patterning and contribution to the skeletal regenerate is currently unresolved. We tested the induction of pattern formation, the effect on cell proliferation, and contributions of skeletal tissues (cartilage, bone, and periosteum) to the regenerating axolotl limb. We found that bone tissue grafts from transgenic donors expressing GFP fail to induce pattern formation and do not contribute to the newly regenerated skeleton. Periosteum tissue grafts, on the other hand, have both of these activities. These observations reveal that skeletal tissue does not contribute to the regeneration of skeletal elements; rather, these structures are patterned by and derived from cells of non-skeletal connective tissue origin. Copyright © 2016 Elsevier Inc. All rights reserved.

Carbon, nitrogen and oxygen isotope fractionation during food cooking: Implications for the interpretation of the fossil human record.

Science.gov (United States)

Royer, Aurélien; Daux, Valérie; Fourel, François; Lécuyer, Christophe

2017-08-01

Stable isotope data provide insight into the reconstruction of ancient human diet. However, cooking may alter the original stable isotope compositions of food due to losses and modifications of biochemical and water components. To address this issue, carbon, nitrogen and oxygen isotope ratios were measured on meat aliquots sampled from various animals such as pork, beef, duck and chicken, and also from the flesh of fishes such as salmon, European seabass, European pilchard, sole, gilt-head bream, and tuna. For each specimen, three pieces were cooked according to the three most commonly-known cooking practices: boiling, frying and roasting on a barbecue. Our data show that cooking produced isotopic shifts up to 1.8‰, 3.5‰, and 5.2‰ for δ 13 C, δ 15 N, and δ 18 O values, respectively. Such variations between raw and cooked food are much greater than previously estimated in the literature; they are more sensitive to the type of food rather than to the cooking process itself, except in the case of boiling. Reconstructions of paleodietary may thus suffer slight bias in cases of populations with undiversified diets that are restrained toward a specific raw or cooked product, or using a specific cooking mode. In cases of oxygen isotope compositions from skeletal remains (bones, teeth), they not only constitute a valuable proxy for reconstructing past climatic conditions, but they could also be used to improve our knowledge of past human diet. © 2017 Wiley Periodicals, Inc.

Skeletal muscle proteins: a new approach to delimitate the time since death.

Science.gov (United States)

Foditsch, Elena Esra; Saenger, Alexandra Maria; Monticelli, Fabio Carlo

2016-03-01

Skeletal muscle tissue is proposed as a forensic model tissue with strong potential, as it is easily accessible and its true-to-life state structure and function is well known. Despite this strong potential, skeletal muscle degradation studies are rare. The aim of this study was to test if a skeletal muscle-based protein analysis is applicable to delimitate the time since death. Under standard conditions, two pigs were stored either at 22 °C for 5 days or 4 °C for 21 days. Their Mm. biceps femori were sampled periodically for analyses of ten skeletal muscle proteins postmortem. All analyzed proteins can serve as markers for a delimitation of the time since death. Desmin, nebulin, titin, and SERCA 1 displayed distinct protein patterns at certain points of time. The other five proteins, α-actinin, calsequestrin-1, laminin, troponin T-C, and SERCA 2, showed no degradation patterns within the analyzed postmortem time frame. Referring to specific skeletal muscle proteins, results showed short-term stabilities for just a minority of analyzed proteins, while the majority of investigated proteins displayed characteristics as long-term markers. Due to specific patterns and the possibility to determine definite constraints of the presence, absence, or pattern alterations of single proteins, the feasibility of porcine skeletal muscle as forensic model tissue is outlined and the potential of skeletal muscle as forensic model tissue is underlined, especially with respect to later postmortem phases, which so far lack feasible methods to delimitate the time since death.

Enhancement of contractile force generation of artificial skeletal muscle tissues by mild and transient heat treatment.

Science.gov (United States)

Sato, Masanori; Ikeda, Kazushi; Kanno, Shota; Ito, Akira; Kawabe, Yoshinori; Kamihira, Masamichi

2014-01-01

Artificial skeletal muscle tissues composed of cells are expected to be used for applications of regenerative medicine and drug screening. Generally, however, the physical forces generated by tissue-engineered skeletal muscle are lower than those of skeletal muscle tissues found in the body. Local hyperthermia is used for many diseases including muscle injuries. It was recently reported that mild heat treatment improved skeletal muscle functions. In this study, we investigated the effects of mild heat treatment on the tissue-engineered skeletal muscle tissues in vitro. We used magnetite cationic liposomes to label C2C12 myoblast cells magnetically, and constructed densely packed artificial skeletal muscle tissues by using magnetic force. Cell culture at 39°C promoted the differentiation of myoblast cells into myotubes. Moreover, the mild and transient heat treatment improved the contractile properties of artificial skeletal muscle tissue constructs. These findings indicate that the culture method using heat treatment is a useful approach to enhance functions of artificial skeletal muscle tissue.

[Study on the difference of corresponding age at cervical vertebral maturation stages among different skeletal malocclusions].

Science.gov (United States)

Zuo, Changyan; Cong, Chao; Wang, Shihui; Gu, Yan

2015-10-01

To compare the difference of corresponding age at cervical vertebral maturation (CVM) stages among different skeletal malocclusions and provide clinic guideline on optimal treatment timing for skeletal malocclusion. Based on ANB angle, 2 575 cephalograms collected from Department of Orthodontics, Peking University School and Hospital of Stomatology from May, 2006 to November, 2014 were classified into skeletal Class I (ANB 0°~5°, 1 317 subjects), Class II (ANB > 5°, 685 subjects) and Class III (ANB < 0°, 573 subjects) groups. CVM stages were evaluated with the modified version of CVM method. Independent sample t test was performed to analyze the difference of age at different CVM stages among various skeletal groups. Significant gender difference of age was found at CS3 to CS6 for skeletal Class I group (P < 0.05), at CS5 and CS6 for skeletal Class II group (P < 0.05), and at CS3 and CS5 for skeletal Class III group (P < 0.05). At CS3 stage, the average age of male in skeletal Class II and skeletal Class III groups was (11.6 ± 1.5) years old and (10.3 ± 1.9) years old, respectively; the average age of females in those two groups was (11.7 ± 1.3) years old and (9.3 ± 1.5) years old, respectively, and significant difference was found in both comparisons (P < 0.05). Compared average age at CS5 and CS6 between skeletal Class II and skeletal Class III groups [the ages of male was (15.1 ± 1.7) and (16.8 ± 1.6) years old, the ages of male was (14.6 ± 1.2) and (15.7 ± 2.5) years old], significant difference was also found (P < 0.05). Significant gender differences were found when evaluated CVM stage and age in skeletal Class I, II and III groups. Significant differences of age at different CVM stage was noted when skeletal Class II was compared with skeletal Class III groups.

Quantification of Skeletal and Dental Changes Associated with the Forsus (trademark) Appliance: A Comparison of Treatment Effects Observed During and Following Peak Growth Velocity

Science.gov (United States)

2012-04-30

their cervical vertebral maturation (CVM) status as determined from a lateral cephalogram taken at the initiation of Forsus™ therapy. Superimpositions...consistent sex difference in skeletal age to the rate of facial growth (Smith 1980). Currently the Cervical Vertebral Maturation Method has been used...orthodontic records of 54 subjects were evaluated. Patients were divided into two treatment groups based on cervical vertebral maturation status

Core top confirmation of the carbonate ion effect in multiple species of planktic foraminifera and a reassessment of the upper water column equatorial Pacific δ13CFORAM records.

Science.gov (United States)

Fehrenbacher, J. S.; Spero, H. J.

2017-12-01

Planktic foraminifera carbon (δ13CFORAM) and oxygen (δ18OFORAM) isotope records play a vital role in paleoceanographic reconstructions. The δ18OFORAM values are typically minimally offset from equilibrium δ18O-calcite and are widely applied in oceanographic reconstructions of upper water column hydrography. In contrast, δ13CFORAM are underutilized in paleoceanographic reconstructions. δ13CFORAM are more difficult to interpret due to species-specific δ13CFORAM offsets from the δ13C of the dissolved inorganic carbon of seawater (δ13CDIC). In this study, we analyzed the δ18OFORAM and δ13CFORAM of individual foraminifera shells from a suite of planktic foraminifer species obtained from core top (Holocene) intervals from Eastern Equatorial Pacific (TR163-19), Western Caribbean (ODP 999A), and Equatorial Indian Ocean (ODP 714A) cores. We also include published records from the Western Equatorial Pacific (MW91-9 15GGC). We find the δ13CFORAM offsets from the local water column δ13CDIC are large, variable, region specific, and are correlated to the ambient carbonate ion concentration ([CO32-]) of seawater. We show that the regional offsets from δ13CDIC are due to the carbonate ion effect (CIE) on δ13CFORAM (Spero et al., 1997; Bijma et al., 1999) and variations in water column [CO32-]. More importantly, our results demonstrate that regional and/or culture based δ13CFORAM offsets from δ13CDIC are not applicable globally. Rather, owing to regional differences in water column [CO32-] and species-specific relationships between [CO32-] and δ13CFORAM, δ13CFORAM must be corrected for the regional CIE in order to infer vertical δ13CDIC gradients or to compare δ13CFORAM records from one region to another. Laboratory culture suggests the carbonate ion effect on δ18OFORAM is 1/3 that of δ13CFORAM (Spero et al., 1997). Thus, in order to obtain correct δ18OFORAM temperatures or δ18OSW (when used in conjunction with Mg/Ca) the δ18OFORAM offsets from δ18

Direct and indirect assessment of skeletal muscle blood flow in chronic congestive heart failure

International Nuclear Information System (INIS)

LeJemtel, T.H.; Scortichini, D.; Katz, S.

1988-01-01

In patients with chronic congestive heart failure (CHF), skeletal muscle blood flow can be measured directly by the continuous thermodilution technique and by the xenon-133 clearance method. The continuous thermodilution technique requires retrograde catheterization of the femoral vein and, thus, cannot be repeated conveniently in patients during evaluation of pharmacologic interventions. The xenon-133 clearance, which requires only an intramuscular injection, allows repeated determination of skeletal muscle blood flow. In patients with severe CHF, a fixed capacity of the skeletal muscle vasculature to dilate appears to limit maximal exercise performance. Moreover, the changes in peak skeletal muscle blood flow noted during long-term administration of captopril, an angiotensin-converting enzyme inhibitor, appears to correlate with the changes in aerobic capacity. In patients with CHF, resting supine deep femoral vein oxygen content can be used as an indirect measurement of resting skeletal muscle blood flow. The absence of a steady state complicates the determination of peak skeletal muscle blood flow reached during graded bicycle or treadmill exercise in patients with chronic CHF. Indirect assessments of skeletal muscle blood flow and metabolism during exercise performed at submaximal work loads are currently developed in patients with chronic CHF

Extrarenal potassium adaptation: role of skeletal muscle

International Nuclear Information System (INIS)

Blachley, J.D.; Crider, B.P.; Johnson, J.H.

1986-01-01

Following the ingestion of a high-potassium-content diet for only a few days, the plasma potassium of rats rises only modestly in response to a previously lethal dose of potassium salts. This acquired tolerance, termed potassium adaptation, is principally the result of increased capacity to excrete potassium into the urine. However, a substantial portion of the acute potassium dose is not immediately excreted and is apparently translocated into cells. Previous studies have failed to show an increase in the content of potassium of a variety of tissues from such animals. Using 86 Rb as a potassium analogue, we have shown that the skeletal muscle of potassium-adapted rats takes up significantly greater amounts of potassium in vivo in response to an acute challenge than does that of control animals. Furthermore, the same animals exhibit greater efflux of 86 Rb following the termination of the acute infusion. We have also shown that the Na+-K+-ATPase activity and ouabain-binding capacity of skeletal muscle microsomes are increased by the process of potassium adaptation. We conclude that skeletal muscle is an important participant in potassium adaptation and acts to temporarily buffer acute increases in the extracellular concentration of potassium

Insulin Increases Ceramide Synthesis in Skeletal Muscle

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M. E. Hansen

2014-01-01

Full Text Available Aims. The purpose of this study was to determine the effect of insulin on ceramide metabolism in skeletal muscle. Methods. Skeletal muscle cells were treated with insulin with or without palmitate for various time periods. Lipids (ceramides and TAG were isolated and gene expression of multiple biosynthetic enzymes were quantified. Additionally, adult male mice received daily insulin injections for 14 days, followed by muscle ceramide analysis. Results. In muscle cells, insulin elicited an increase in ceramides comparable to palmitate alone. This is likely partly due to an insulin-induced increase in expression of multiple enzymes, particularly SPT2, which, when knocked down, prevented the increase in ceramides. In mice, 14 days of insulin injection resulted in increased soleus ceramides, but not TAG. However, insulin injections did significantly increase hepatic TAG compared with vehicle-injected animals. Conclusions. This study suggests that insulin elicits an anabolic effect on sphingolipid metabolism in skeletal muscle, resulting in increased ceramide accumulation. These findings reveal a potential mechanism of the deleterious consequences of the hyperinsulinemia that accompanies insulin resistance and suggest a possible novel therapeutic target to mitigate its effects.

A primary reduced TCA flux governs substrate oxidation in T2D skeletal muscle

DEFF Research Database (Denmark)

Gaster, Michael

2012-01-01

Our current knowledge on substrate oxidation in skeletal muscle in relation to insulin resistance and type 2 diabetes (T2D) originate mainly from in vivo studies. The oxidative capacity of skeletal muscle is highly influenced by physical activity, ageing, hormonal status, and fiber type composition...... further regulatory mechanism to our understanding of substrate oxidation in human skeletal muscle during normo- an pathophysiological conditions, focusing especially on the governing influence of a primary reduced TCA flux for the diabetic phenotype in skeletal muscle....

The impact of local winds and long-range transport on the continuous carbon dioxide record at Mount Waliguan, China

International Nuclear Information System (INIS)

Lingxi Zhou; Jie Tang; Yupu Wen; Peng Yan; Jinlong Li

2003-01-01

This paper describes the continuous measurements of atmospheric carbon dioxide at Mt. Waliguan (36 deg 17 min N, 100 deg 54 min E, 3816 m asl) in western China over the period 1994-2000. The CO 2 hourly mixing ratios were segregated by horizontal wind direction/speed and vertical winds, respectively, merged by season over the entire measurement period. The short-term variability in CO 2 was examined mainly from the point of view of local winds observed at this station and isobaric back trajectory cluster-concentration analysis as for local and long-range transport influence, to permit the selection of hourly average data that is representative of background conditions. From the selected hourly data, daily, monthly and annual averages that are not influenced by local CO 2 sources and sinks be computed by discriminating the local and regional impact on the Waliguan CO 2 records. On the basis of these results, background CO 2 data were then analyzed to evaluate the averaged diurnal variation, monthly mean time series, CO 2 mixing ratio distribution in different seasons as well as averaged seasonal cycle. Annual mean and growth rate of CO 2 at Waliguan during the period of 1991 to 2000 were further discussed by supplement with NOAA/CMDL flask air sampling records at this station and other monitoring stations located at similar latitudinal band in the Northern Hemisphere. The results from this study can provide atmospheric CO 2 characteristics in Asian inland regions, and be used in other studies to improve the understanding of carbon source and sink distributions

A description and comparison of selected forest carbon registries: a guide for States considering the development of a forest carbon registry

Science.gov (United States)

Jessica Call; Jennifer Hayes

2007-01-01

There is increasing interest in tools for measuring and reducing emissions of carbon dioxide, a major greenhouse gas. Two tools that have been receiving a lot of attention include carbon markets and carbon registries. Carbon registries are established to record and track net carbon emission levels over time. These registries provide quantifiable and verifiable carbon...

Temperature and composition of carbonate cements record early structural control on cementation in a nascent deformation band fault zone: Moab Fault, Utah, USA

Science.gov (United States)

Hodson, Keith R.; Crider, Juliet G.; Huntington, Katharine W.

2016-10-01

Fluid-driven cementation and diagenesis within fault zones can influence host rock permeability and rheology, affecting subsequent fluid migration and rock strength. However, there are few constraints on the feedbacks between diagenetic conditions and structural deformation. We investigate the cementation history of a fault-intersection zone on the Moab Fault, a well-studied fault system within the exhumed reservoir rocks of the Paradox Basin, Utah, USA. The fault zone hosts brittle structures recording different stages of deformation, including joints and two types of deformation bands. Using stable isotopes of carbon and oxygen, clumped isotope thermometry, and cathodoluminescence, we identify distinct source fluid compositions for the carbonate cements within the fault damage zone. Each source fluid is associated with different carbonate precipitation temperatures, luminescence characteristics, and styles of structural deformation. Luminescent carbonates appear to be derived from meteoric waters mixing with an organic-rich or magmatic carbon source. These cements have warm precipitation temperatures and are closely associated with jointing, capitalizing on increases in permeability associated with fracturing during faulting and subsequent exhumation. Earlier-formed non-luminescent carbonates have source fluid compositions similar to marine waters, low precipitation temperatures, and are closely associated with deformation bands. The deformation bands formed at shallow depths very early in the burial history, preconditioning the rock for fracturing and associated increases in permeability. Carbonate clumped isotope temperatures allow us to associate structural and diagenetic features with burial history, revealing that structural controls on fluid distribution are established early in the evolution of the host rock and fault zone, before the onset of major displacement.

Skeletal deformities of acardius anceps: the gross and imaging features

Energy Technology Data Exchange (ETDEWEB)

Chen Chihping [Dept. of Medical Research, Mackay Memorial Hospital, Taipei (Taiwan, Province of China); Shih Shinlin [Dept. of Radiology, Mackay Memorial Hospital, Taipei (Taiwan, Province of China); Liu Fenfen [Dept. of Medical Research, Mackay Memorial Hospital, Taipei (Taiwan, Province of China); Jan Sheauwen [Dept. of Medical Research, Mackay Memorial Hospital, Taipei (Taiwan, Province of China); Lin Yunnan [Dept. of Pathology, Mackay Memorial Hospital, Taipei (Taiwan, Province of China); Lan Chungchi [Dept. of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei (Taiwan, Province of China)

1997-03-01

A morphology based imaging review is presented of the characteristic skeletal deformities associated with acardius anceps in three acardiac twins. These fetuses demonstrated poorly developed skulls, limb reduction defects, and phocomelia of the upper limbs, as well as narrow thoracic cages with or without the complete development of ribs, clavicles, scapulae, and cervical, thoracic, or lumbar vertebrae. However, their lower limbs and pelvic girdles were almost normal. The authors conclude that skeletal development is likely to be jeopardized in the area adjacent to the heart and in the cephalic portion of the body in fetuses with acardius anceps, and suggest vascular deficiency and hypoperfusion as pathogenetic mechanisms in this type of skeletal deformity. (orig.)

Skeletal deformities of acardius anceps: the gross and imaging features

International Nuclear Information System (INIS)

Chen Chihping; Shih Shinlin; Liu Fenfen; Jan Sheauwen; Lin Yunnan; Lan Chungchi

1997-01-01

A morphology based imaging review is presented of the characteristic skeletal deformities associated with acardius anceps in three acardiac twins. These fetuses demonstrated poorly developed skulls, limb reduction defects, and phocomelia of the upper limbs, as well as narrow thoracic cages with or without the complete development of ribs, clavicles, scapulae, and cervical, thoracic, or lumbar vertebrae. However, their lower limbs and pelvic girdles were almost normal. The authors conclude that skeletal development is likely to be jeopardized in the area adjacent to the heart and in the cephalic portion of the body in fetuses with acardius anceps, and suggest vascular deficiency and hypoperfusion as pathogenetic mechanisms in this type of skeletal deformity. (orig.)

Developmental changes of protein, RNA, DNA, lipid, and glycogen in the liver, skeletal muscle, and brain of the piglet

International Nuclear Information System (INIS)

Hakkarainen, J.

1975-01-01

A scheme for the sequential quantitative separation and determination of protein, RNA, DNA, lipid, and glycogen from rat-liver homogenate is modified for application to frozen tissues of the piglet. The biochemical methods, including the biuret method, used in the present investigation are described and thoroughly checked. The effects of freezing and storage on the recovery of major tissue constituents are recorded. The modified scheme is applied to the determination of protein, RNA, DNA, lipid, and glycogen in the liver, skeletal muscle, and brain of the developing piglet. Developmental changes for these major tissue constituents, including the biuret protein, are described with special reference to protein synthesis and physiology of growth at the cellular level from 45 days of foetal age to 35-42 days of postnatal age for liver and skeletal muscle, and from birth to 31-40 days of postnatal age for the cerebrum and cerebellum. The uniformly labelled amino acid, 14 C-L-leucine, is used to study protein synthesis. Developmental patterns of labelling of protein and lipid in the liver, skeletal muscle, cerebrum, and cerebellum of the piglet from birth up to the age of two weeks are described. The results of the methodological, developmental, and experimental studies are thoroughly discussed in the light of the relevant literature and compared with those obtained in developmental and experimental studies on rats and other mammal species. (author)

Docosahexaenoic acid and n-6 docosapentaenoic acid supplementation alter rat skeletal muscle fatty acid composition

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Lim Sun-Young

2007-04-01

Full Text Available Abstract Background Docosahexaenoic acid (22:6n-3, DHA and n-6 docosapentaenoic acid (22:5n-6, DPAn-6 are highly unsaturated fatty acids (HUFA, ≥ 20 carbons, ≥ 3 double bonds that differ by a single carbon-carbon double bond at the Δ19 position. Membrane 22:6n-3 may support skeletal muscle function through optimal ion pump activity of sarcoplasmic reticulum and electron transport in the mitochondria. Typically n-3 fatty acid deficient feeding trials utilize linoleic acid (18:2n-6, LA as a comparison group, possibly introducing a lower level of HUFA in addition to n-3 fatty acid deficiency. The use of 22:5n-6 as a dietary control is ideal for determining specific requirements for 22:6n-3 in various physiological processes. The incorporation of dietary 22:5n-6 into rat skeletal muscles has not been demonstrated previously. A one generation, artificial rearing model was utilized to supply 22:6n-3 and/or 22:5n-6 to rats from d2 after birth to adulthood. An n-3 fatty acid deficient, artificial milk with 18:2n-6 was supplemented with 22:6n-3 and/or 22:5n-6 resulting in four artificially reared (AR dietary groups; AR-LA, AR-DHA, AR-DPAn-6, AR-DHA+DPAn-6. A dam reared group (DAM was included as an additional control. Animals were sacrificed at 15 wks and soleus, white gastrocnemius and red gastrocnemius muscles were collected for fatty acid analyses. Results In all muscles of the DAM group, the concentration of 22:5n-6 was significantly lower than 22:6n-3 concentrations. While 22:5n-6 was elevated in the AR-LA group and the AR-DPAn-6 group, 20:4n-6 tended to be higher in the AR-LA muscles and not in the AR-DPAn-6 muscles. The AR-DHA+DPAn-6 had a slight, but non-significant increase in 22:5n-6 content. In the red gastrocnemius of the AR-DPAn-6 group, 22:5n-6 levels (8.1 ± 2.8 wt. % did not reciprocally replace the 22:6n-3 levels observed in AR-DHA reared rats (12.2 ± 2.3 wt. % suggesting a specific preference/requirement for 22:6n-3 in red

Orthognathic Surgery for the Correction of Severe Skeletal Class III Malocclusion.

Science.gov (United States)

Kafle, D; Upadhayaya, C; Chaurasia, N; Agarwal, A

2016-01-01

Skeletal Malocclusions results from the abnormal position of maxilla and mandible in relation with cranial base. These types of malocclusion are commonly treated by orthodontic teeth movement known as camouflage orthodontics. However severe skeletal malocclusions cannot be treated by orthodontics alone. Such cases need surgical intervention to align the position of the jaw along with orthodontic correction. This procedure is commonly known as Orthognathic Surgery. Orthognathic Surgery dates back to early eighteenth century but became popular on mid twentieth century. Though the prevalence of skeletal malocclusion is more than 1% the treatment facility was not available in Nepal till 2012. Here we present a case of Skeletal Class III malocclusion treated at Dhulikhel Hospital, Kathmandu University Hospital. For this case, double jaw surgery was performed by le-Fort I osteotomy and Bilateral Sagital Split Osteotomy. Orthognathic surgery has been routinely performed at this centre since then.

Adult Murine Skeletal Muscle Contains Cells That Can Differentiate into Beating Cardiomyocytes In Vitro

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Winitsky Steve O

2005-01-01

Full Text Available It has long been held as scientific fact that soon after birth, cardiomyocytes cease dividing, thus explaining the limited restoration of cardiac function after a heart attack. Recent demonstrations of cardiac myocyte differentiation observed in vitro or after in vivo transplantation of adult stem cells from blood, fat, skeletal muscle, or heart have challenged this view. Analysis of these studies has been complicated by the large disparity in the magnitude of effects seen by different groups and obscured by the recently appreciated process of in vivo stem-cell fusion. We now show a novel population of nonsatellite cells in adult murine skeletal muscle that progress under standard primary cell-culture conditions to autonomously beating cardiomyocytes. Their differentiation into beating cardiomyocytes is characterized here by video microscopy, confocal-detected calcium transients, electron microscopy, immunofluorescent cardiac-specific markers, and single-cell patch recordings of cardiac action potentials. Within 2 d after tail-vein injection of these marked cells into a mouse model of acute infarction, the marked cells are visible in the heart. By 6 d they begin to differentiate without fusing to recipient cardiac cells. Three months later, the tagged cells are visible as striated heart muscle restricted to the region of the cardiac infarct.

Adult murine skeletal muscle contains cells that can differentiate into beating cardiomyocytes in vitro.

Directory of Open Access Journals (Sweden)

Steve O Winitsky

2005-04-01

Full Text Available It has long been held as scientific fact that soon after birth, cardiomyocytes cease dividing, thus explaining the limited restoration of cardiac function after a heart attack. Recent demonstrations of cardiac myocyte differentiation observed in vitro or after in vivo transplantation of adult stem cells from blood, fat, skeletal muscle, or heart have challenged this view. Analysis of these studies has been complicated by the large disparity in the magnitude of effects seen by different groups and obscured by the recently appreciated process of in vivo stem-cell fusion. We now show a novel population of nonsatellite cells in adult murine skeletal muscle that progress under standard primary cell-culture conditions to autonomously beating cardiomyocytes. Their differentiation into beating cardiomyocytes is characterized here by video microscopy, confocal-detected calcium transients, electron microscopy, immunofluorescent cardiac-specific markers, and single-cell patch recordings of cardiac action potentials. Within 2 d after tail-vein injection of these marked cells into a mouse model of acute infarction, the marked cells are visible in the heart. By 6 d they begin to differentiate without fusing to recipient cardiac cells. Three months later, the tagged cells are visible as striated heart muscle restricted to the region of the cardiac infarct.

Radiotherapy of pathologic fractures and skeletal lesions bearing the risk of fracture

International Nuclear Information System (INIS)

Rieden, K.; Kober, B.; Mende, U.; Zum Winkel, K.

1986-01-01

Radiotherapy is of great importance in the treatment of pathologic fractures and skeletal lesions bearing the risk of fracture which are induced by malignomas, especially if these are in an advanced stage. In dependence on site and extent of skeletal destruction as well as on the general tumor dissemination, it can be distinguished between palliative radiotherapy and curative radiotherapy aiming at analgesia and remineralization. A retrospective analysis of 27 pathologic fractures and 56 skeletal lesions bearing the risk of fracture in malignoma patients showed an analgetic effect obtained by radiotherapy in 67% of pathological fractures and in 80% of skeletal lesions bearing the risk of fracture, whereas a remineralization could be demonstrated for 33% of pathological fractures and 50% of destructions bearing the risk of fracture. A stabilization of destructions progressing before therapy was found in 55% of pathological fractures and 40% of skeletal lesions bearing the risk of fracture. Thus a partial loading, supported by orthopedic prostheses, was possible for more than 50% of all patients. (orig.) [de

Tribbles 3 Mediates Endoplasmic Reticulum Stress-Induced Insulin Resistance in Skeletal Muscle

Science.gov (United States)

Koh, Ho-Jin; Toyoda, Taro; Didesch, Michelle M.; Lee, Min-Young; Sleeman, Mark W.; Kulkarni, Rohit N.; Musi, Nicolas; Hirshman, Michael F.; Goodyear, Laurie J.

2013-01-01

Endoplasmic Reticulum (ER) stress has been linked to insulin resistance in multiple tissues but the role of ER stress in skeletal muscle has not been explored. ER stress has also been reported to increase tribbles 3 (TRB3) expression in multiple cell lines. Here, we report that high fat feeding in mice, and obesity and type 2 diabetes in humans significantly increases TRB3 and ER stress markers in skeletal muscle. Overexpression of TRB3 in C2C12 myotubes and mouse tibialis anterior muscles significantly impairs insulin signaling. Incubation of C2C12 cells and mouse skeletal muscle with ER stressors thapsigargin and tunicamycin increases TRB3 and impairs insulin signaling and glucose uptake, effects reversed in cells overexpressing RNAi for TRB3 and in muscles from TRB3 knockout mice. Furthermore, TRB3 knockout mice are protected from high fat diet-induced insulin resistance in skeletal muscle. These data demonstrate that TRB3 mediates ER stress-induced insulin resistance in skeletal muscle. PMID:23695665

Radium-223 in treatment of castration-resistant prostate cancer with skeletal metastases

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V. B. Matveev

2017-01-01

Full Text Available More than 90 % of patients with metastatic castration-resistant prostate cancer (CRPC have radiologically confirmed skeletal metastases. Traditional treatment methods such as administration of painkillers, external beam therapy, bisphosphonates or denosumab, as well as injections of strontium-89 or samarium-153 radionuclides, have only palliative effect and in some cases can postpone development of skeletal complications. Alpha-emitter radium-223 dichloride (Ra-223; alpharadin previously is currently one of the known drugs with proven effectiveness in relation to increasing overall survival of patients with CRPC. Ra-223 was developed specifically for patients with CRPC and symptomatic skeletal metastases. The drug targets the areas of skeletal tissue remodeling. Ra-223 is the therapy of choice in patients with CRPC and skeletal metastases and without confirmed visceral metastases before and after docetaxel chemotherapy. Chemotherapy after treatment with Ra-223 is a possible and satisfactory tolerable treatment option. Combination of Ra-223 with abiraterone, enzalutamide, or denosumab is, apparently, effective and safe, but further studies are necessary.

Deciphering Complex Carbon Cycle Changes Across the K-Pg Boundary Using Compound-Specific Carbon Isotopic Analyses

Science.gov (United States)

Pancost, R. D.; Taylor, K. W.; Hollis, C. J.; Crouch, E. M.

2014-12-01

The consequences of the Cretaceous-Paleogene (K/Pg) boundary event on the Earth system have been the subject of much scrutiny. Postulated climate events include a brief (10 - 2000 yr) period of global cooling induced by sulphate aerosols (the so-called 'impact winter'), an interval of warming caused by impact-induced CO2release, as well as longer-term climatic oscillations during the subsequent 1 to 3Myr. Associated with these were putative changes in the biogeochemical cycle, manifested as carbon isotope excursions on both short- and long-term timescales. In this study we develop new biomarker-based climate and biogeochemical records for the mid-Waipara River and Branch Stream sections, NZ. At Branch Stream, a pronounced negative (ca 6 to 8 permil) carbon isotope excursion occurs at the K/Pg; the excursion is recorded by higher plant biomarkers, consistent with some terrestrial records and suggesting that the immediate aftermath of the K/Pg boundary event was characterised by the massive release of 13C-depleted reduced carbon into the ocean-atmosphere reservoir. Mixing across the K/Pg boundary at the Waipara section precludes a similar high-resolution investigation. Lower-resolution, longer-term records, however, also reveal a negative carbon istope excursion documented by both algal and higher plant biomarkers. This event appears to be distinct from that recorded at Branch Stream, being of lower magnitude and longer duration. It coincided with a transient terrestrial and marine warming and appears to have lasted at least 100 kyr and perhaps longer. We argue that this protracted negative CIE reflects a secondary and longer-term consequence of the K/Pg on the global carbon cycle. There is little evidence for an algal extinction as a range of C27 to C30 sterols continued to be deposited throughout the entire section, but changes in GDGT distributions do suggest a change in carbon export dynamics which could have impacted burial of 13C-depleted marine organic matter

Changes in skeletal muscle gene expression following clenbuterol administration

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McIntyre Lauren M

2006-12-01

Full Text Available Abstract Background Beta-adrenergic receptor agonists (BA induce skeletal muscle hypertrophy, yet specific mechanisms that lead to this effect are not well understood. The objective of this research was to identify novel genes and physiological pathways that potentially facilitate BA induced skeletal muscle growth. The Affymetrix platform was utilized to identify gene expression changes in mouse skeletal muscle 24 hours and 10 days after administration of the BA clenbuterol. Results Administration of clenbuterol stimulated anabolic activity, as indicated by decreased blood urea nitrogen (BUN; P P Conclusion Global evaluation of gene expression after administration of clenbuterol identified changes in gene expression and overrepresented functional categories of genes that may regulate BA-induced muscle hypertrophy. Changes in mRNA abundance of multiple genes associated with myogenic differentiation may indicate an important effect of BA on proliferation, differentiation, and/or recruitment of satellite cells into muscle fibers to promote muscle hypertrophy. Increased mRNA abundance of genes involved in the initiation of translation suggests that increased levels of protein synthesis often associated with BA administration may result from a general up-regulation of translational initiators. Additionally, numerous other genes and physiological pathways were identified that will be important targets for further investigations of the hypertrophic effect of BA on skeletal muscle.

Aberrant mitochondrial homeostasis in the skeletal muscle of sedentary older adults.

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Adeel Safdar

Full Text Available The role of mitochondrial dysfunction and oxidative stress has been extensively characterized in the aetiology of sarcopenia (aging-associated loss of muscle mass and muscle wasting as a result of muscle disuse. What remains less clear is whether the decline in skeletal muscle mitochondrial oxidative capacity is purely a function of the aging process or if the sedentary lifestyle of older adult subjects has confounded previous reports. The objective of the present study was to investigate if a recreationally active lifestyle in older adults can conserve skeletal muscle strength and functionality, chronic systemic inflammation, mitochondrial biogenesis and oxidative capacity, and cellular antioxidant capacity. To that end, muscle biopsies were taken from the vastus lateralis of young and age-matched recreationally active older and sedentary older men and women (N = 10/group; female symbol = male symbol. We show that a physically active lifestyle is associated with the partial compensatory preservation of mitochondrial biogenesis, and cellular oxidative and antioxidant capacity in skeletal muscle of older adults. Conversely a sedentary lifestyle, associated with osteoarthritis-mediated physical inactivity, is associated with reduced mitochondrial function, dysregulation of cellular redox status and chronic systemic inflammation that renders the skeletal muscle intracellular environment prone to reactive oxygen species-mediated toxicity. We propose that an active lifestyle is an important determinant of quality of life and molecular progression of aging in skeletal muscle of the elderly, and is a viable therapy for attenuating and/or reversing skeletal muscle strength declines and mitochondrial abnormalities associated with aging.

Use of Targeted Exome Sequencing for Molecular Diagnosis of Skeletal Disorders

Science.gov (United States)

Polla, Daniel L.; Cardoso, Maria T. O.; Silva, Mayara C. B.; Cardoso, Isabela C. C.; Medina, Cristina T. N.; Araujo, Rosenelle; Fernandes, Camila C.; Reis, Alessandra M. M.; de Andrade, Rosangela V.; Pereira, Rinaldo W.; Pogue, Robert

2015-01-01

Genetic disorders of the skeleton comprise a large group of more than 450 clinically distinct and genetically heterogeneous diseases associated with mutations in more than 300 genes. Achieving a definitive diagnosis is complicated due to the genetic heterogeneity of these disorders, their individual rarity and their diverse radiographic presentations. We used targeted exome sequencing and designed a 1.4Mb panel for simultaneous testing of more than 4,800 exons in 309 genes involved in skeletal disorders. DNA from 69 individuals from 66 families with a known or suspected clinical diagnosis of a skeletal disorder was analyzed. Of 36 cases with a specific clinical hypothesis with a known genetic basis, mutations were identified for eight cases (22%). Of 20 cases with a suspected skeletal disorder but without a specific diagnosis, four causative mutations were identified. Also included were 11 cases with a specific skeletal disorder but for which there was at the time no known associated gene. For these cases, one mutation was identified in a known skeletal disease genes, and re-evaluation of the clinical phenotype in this case changed the diagnoses from osteodysplasia syndrome to Apert syndrome. These results suggest that the NGS panel provides a fast, accurate and cost-effective molecular diagnostic tool for identifying mutations in a highly genetically heterogeneous set of disorders such as genetic skeletal disorders. The data also stress the importance of a thorough clinical evaluation before DNA sequencing. The strategy should be applicable to other groups of disorders in which the molecular basis is largely known. PMID:26380986

Treatment outcome and long-term stability of skeletal changes following maxillary distraction in adult subjects of cleft lip and palate

OpenAIRE

Satinder Pal Singh; Ashok Kumar Jena; Vidya Rattan; Ashok Kumar Utreja

2012-01-01

Aim : To evaluate the treatment outcome and long-term stability of skeletal changes following maxillary advancement with distraction osteogenesis in adult subjects of cleft lip and palate. Materials and Methods: Total 12 North Indian adult patients in the age range of 17-34 years with cleft lip and palate underwent advancement of maxilla by distraction osteogenesis. Lateral cephalograms recorded prior to distraction, at the end of distraction, 6 months after distraction, and at least 24 month...

Suppression of CHRN endocytosis by carbonic anhydrase CAR3 in the pathogenesis of myasthenia gravis.

Science.gov (United States)

Du, Ailian; Huang, Shiqian; Zhao, Xiaonan; Feng, Kuan; Zhang, Shuangyan; Huang, Jiefang; Miao, Xiang; Baggi, Fulvio; Ostrom, Rennolds S; Zhang, Yanyun; Chen, Xiangjun; Xu, Congfeng

2017-01-01

Myasthenia gravis is an autoimmune disorder of the neuromuscular junction manifested as fatigable muscle weakness, which is typically caused by pathogenic autoantibodies against postsynaptic CHRN/AChR (cholinergic receptor nicotinic) in the endplate of skeletal muscle. Our previous studies have identified CA3 (carbonic anhydrase 3) as a specific protein insufficient in skeletal muscle from myasthenia gravis patients. In this study, we investigated the underlying mechanism of how CA3 insufficiency might contribute to myasthenia gravis. Using an experimental autoimmune myasthenia gravis animal model and the skeletal muscle cell C2C12, we find that inhibition of CAR3 (the mouse homolog of CA3) promotes CHRN internalization via a lipid raft-mediated pathway, leading to accelerated degradation of postsynaptic CHRN. Activation of CAR3 reduces CHRN degradation by suppressing receptor endocytosis. CAR3 exerts this effect by suppressing chaperone-assisted selective autophagy via interaction with BAG3 (BCL2-associated athanogene 3) and by dampening endoplasmic reticulum stress. Collectively, our study illustrates that skeletal muscle cell CAR3 is critical for CHRN homeostasis in the neuromuscular junction, and its deficiency leads to accelerated degradation of CHRN and development of myasthenia gravis, potentially revealing a novel therapeutic approach for this disorder.

Computed tomography guidance for skeletal biopsy

International Nuclear Information System (INIS)

Frager, D.H.; Goldman, M.J.; Elkin, C.M.; Cynamon, J.; Leeds, N.E.; Seimon, L.P.; Habermann, E.T.; Schreiber, K.; Freeman, L.M.

1987-01-01

Computed tomographic (CT) guided biopsy and abscess drainage of multiple organ systems have been well described. Reports of spinal and skeletal applications have been less common. This study describes the use of CT guidance in the biopsy of various skeletal lesions in 46 patients. Forty-one patients had skinny needle aspirations (18 or 22 gauge) and 23 patients had trephine core biopsies. Sites of the lesions included: thoracic spine - 15 patients, lumbosacral spine - 17 patients, bony pelvis - 6 patients, rib - 2 patients, and long bones - 6 patients. Fast scanners capable of rapid image reconstruction have overcome many constraints. With CT guidance, the physician who performs the procedure receives virtually no ionizing radiation. The exact location of the needle tip is accurately visualized in relation to the lesion being biopsied and to the vital organs. (orig.)

Human skeletal muscle fatty acid and glycerol metabolism during rest, exercise and recovery

DEFF Research Database (Denmark)

Van Hall, Gerrit; Sacchetti, M; Rådegran, G

2002-01-01

glycerol uptake was observed, which was substantially higher during exercise. Total body skeletal muscle FA and glycerol uptake/release was estimated to account for 18-25 % of whole body R(d) or R(a). In conclusion: (1) skeletal muscle FA and glycerol metabolism, using the leg arterial-venous difference......This study was conducted to investigate skeletal muscle fatty acid (FA) and glycerol kinetics and to determine the contribution of skeletal muscle to whole body FA and glycerol turnover during rest, 2 h of one-leg knee-extensor exercise at 65 % of maximal leg power output, and 3 h of recovery....... To this aim, the leg femoral arterial-venous difference technique was used in combination with a continuous infusion of [U-(13)C]palmitate and [(2)H(5)]glycerol in five post-absorptive healthy volunteers (22 +/- 3 years). The influence of contamination from non-skeletal muscle tissues, skin and subcutaneous...

Cardiac, skeletal, and smooth muscle mitochondrial respiration: are all mitochondria created equal?

Science.gov (United States)

Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I; Trinity, Joel D; Hyngstrom, John R; Garten, Ryan S; Diakos, Nikolaos A; Ives, Stephen J; Dela, Flemming; Larsen, Steen; Drakos, Stavros; Richardson, Russell S

2014-08-01

Unlike cardiac and skeletal muscle, little is known about vascular smooth muscle mitochondrial respiration. Therefore, the present study examined mitochondrial respiratory rates in smooth muscle of healthy human feed arteries and compared with that of healthy cardiac and skeletal muscles. Cardiac, skeletal, and smooth muscles were harvested from a total of 22 subjects (53 ± 6 yr), and mitochondrial respiration was assessed in permeabilized fibers. Complex I + II, state 3 respiration, an index of oxidative phosphorylation capacity, fell progressively from cardiac to skeletal to smooth muscles (54 ± 1, 39 ± 4, and 15 ± 1 pmol·s(-1)·mg(-1), P respiration rates were normalized by CS (respiration per mitochondrial content), oxidative phosphorylation capacity was no longer different between the three muscle types. Interestingly, complex I state 2 normalized for CS activity, an index of nonphosphorylating respiration per mitochondrial content, increased progressively from cardiac to skeletal to smooth muscles, such that the respiratory control ratio, state 3/state 2 respiration, fell progressively from cardiac to skeletal to smooth muscles (5.3 ± 0.7, 3.2 ± 0.4, and 1.6 ± 0.3 pmol·s(-1)·mg(-1), P respiration highlight the existence of intrinsic functional differences between these muscle mitochondria. This likely influences the efficiency of oxidative phosphorylation and could potentially alter ROS production.

Postoperative complications associated with external skeletal fixators in cats.

Science.gov (United States)

Beever, Lee; Giles, Kirsty; Meeson, Richard

2017-07-01

The objective of this study was to quantify complications associated with external skeletal fixators (ESFs) in cats and to identify potential risk factors. A retrospective review of medical records and radiographs following ESF placement was performed. Case records of 140 cats were reviewed; fixator-associated complications (FACs) occurred in 19% of cats. The region of ESF placement was significantly associated with complication development. Complications developed most frequently in the femur (50%), tarsus (35%) and radius/ulna (33%). Superficial pin tract infection (SPTI) and implant failure accounted for 45% and 41% of all FACs, respectively. SPTI occurred more frequently in the femur, humerus and tibia, with implant failure more frequent in the tarsus. No association between breed, age, sex, weight, fracture type (open vs closed), ESF classification, number of pins per bone segment, degree of fracture load sharing, and the incidence or type of FAC was identified. No association between region of placement, breed, age, sex, weight, fracture type (open vs closed), ESF classification, number of pins per bone segment, fracture load sharing and the time to complication development was identified. Complication development is not uncommon in cats following ESF placement. The higher complication rate in the femur, tarsus and radius/ulna should be considered when reviewing options for fracture management. However, cats appear to have a lower rate of pin tract infections than dogs.

Creation of a predictive equation to estimate fat-free mass and the ratio of fat-free mass to skeletal size using morphometry in lean working farm dogs.

Science.gov (United States)

Leung, Y M; Cave, N J; Hodgson, B A S

2018-06-27

To develop an equation that accurately estimates fat-free mass (FFM) and the ratio of FFM to skeletal size or mass, using morphometric measurements in lean working farm dogs, and to examine the association between FFM derived from body condition score (BCS) and FFM measured using isotope dilution. Thirteen Huntaway and seven Heading working dogs from sheep and beef farms in the Waikato region of New Zealand were recruited based on BCS (BCS 4) using a nine-point scale. Bodyweight, BCS, and morphometric measurements (head length and circumference, body length, thoracic girth, and fore and hind limb length) were recorded for each dog, and body composition was measured using an isotopic dilution technique. A new variable using morphometric measurements, termed skeletal size, was created using principal component analysis. Models for predicting FFM, leanST (FFM minus skeletal mass) and ratios of FFM and leanST to skeletal size or mass were generated using multiple linear regression analysis. Mean FFM of the 20 dogs, measured by isotope dilution, was 22.1 (SD 4.4) kg and the percentage FFM of bodyweight was 87.0 (SD 5.0)%. Median BCS was 3.0 (min 1, max 6). Bodyweight, breed, age and skeletal size or mass were associated with measured FFM (pFFM and measured FFM (R 2 =0.96), and for the ratio of predicted FFM to skeletal size and measured values (R 2 =0.99). Correlation coefficients were higher for the ratio FFM and leanST to skeletal size than for ratios using skeletal mass. There was a positive correlation between BCS-derived fat mass as a percentage of bodyweight and fat mass percentage determined using isotope dilution (R 2 =0.65). As expected, the predictive equation was accurate in estimating FFM when tested on the same group of dogs used to develop the equation. The significance of breed, independent of skeletal size, in predicting FFM indicates that individual breed formulae may be required. Future studies that apply these equations on a greater population of

A skeletal mechanism for biodiesel blend surrogates combustion

International Nuclear Information System (INIS)

An, H.; Yang, W.M.; Maghbouli, A.; Li, J.; Chua, K.J.

2014-01-01

Highlights: • A skeletal biodiesel reaction mechanism with 112 species was constructed. • The developed mechanism contains the CO, NO x and soot formation kinetics. • It was well validated against detailed reaction mechanism and experimental results. • The mechanism is suitable to simulate biodiesel, diesel and their blend fuels. - Abstract: A tri-component skeletal reaction mechanism consisting of methyl decanoate, methyl-9-decenoate, and n-heptane was developed for biodiesel combustion in diesel engine. It comprises 112 species participating in 498 reactions with the CO, NO x and soot formation mechanisms embedded. In this study, a detailed tri-component biodiesel mechanism was used as the start of mechanism reduction and the reduced mechanism was combined with a previously developed skeletal reaction mechanism for n-heptane to integrate the soot formation kinetics. A combined mechanism reduction strategy including the directed relation graph with error propagation and sensitivity analysis (DRGEPSA), peak concentration analysis, isomer lumping, unimportant reactions elimination and reaction rate adjustment methods was employed. The reduction process for biodiesel was performed over a range of initial conditions covering the pressures from 1 to 100 atm, equivalence ratios from 0.5 to 2.0 and temperatures from 700 to 1800 K, whereas for n-heptane, ignition delay predictions were compared against 17 shock tube experimental conditions. Extensive validations were performed for the developed skeletal reaction mechanism with 0-D ignition delay testing and 3-D engine simulations. The results indicated that the developed mechanism was able to accurately predict the ignition delay timings of n-heptane and biodiesel, and it could be integrated into 3-D engine simulations to predict the combustion characteristics of biodiesel. As such, the developed 112-species skeletal mechanism can accurately mimic the significant reaction pathways of the detailed reaction

HDAC4 preserves skeletal muscle structure following long-term denervation by mediating distinct cellular responses.

Science.gov (United States)

Pigna, Eva; Renzini, Alessandra; Greco, Emanuela; Simonazzi, Elena; Fulle, Stefania; Mancinelli, Rosa; Moresi, Viviana; Adamo, Sergio

2018-02-24

Denervation triggers numerous molecular responses in skeletal muscle, including the activation of catabolic pathways and oxidative stress, leading to progressive muscle atrophy. Histone deacetylase 4 (HDAC4) mediates skeletal muscle response to denervation, suggesting the use of HDAC inhibitors as a therapeutic approach to neurogenic muscle atrophy. However, the effects of HDAC4 inhibition in skeletal muscle in response to long-term denervation have not been described yet. To further study HDAC4 functions in response to denervation, we analyzed mutant mice in which HDAC4 is specifically deleted in skeletal muscle. After an initial phase of resistance to neurogenic muscle atrophy, skeletal muscle with a deletion of HDAC4 lost structural integrity after 4 weeks of denervation. Deletion of HDAC4 impaired the activation of the ubiquitin-proteasome system, delayed the autophagic response, and dampened the OS response in skeletal muscle. Inhibition of the ubiquitin-proteasome system or the autophagic response, if on the one hand, conferred resistance to neurogenic muscle atrophy; on the other hand, induced loss of muscle integrity and inflammation in mice lacking HDAC4 in skeletal muscle. Moreover, treatment with the antioxidant drug Trolox prevented loss of muscle integrity and inflammation in in mice lacking HDAC4 in skeletal muscle, despite the resistance to neurogenic muscle atrophy. These results reveal new functions of HDAC4 in mediating skeletal muscle response to denervation and lead us to propose the combined use of HDAC inhibitors and antioxidant drugs to treat neurogenic muscle atrophy.

Radiological diagnosis of skeletal metastases

International Nuclear Information System (INIS)

Soederlund, V.

1996-01-01

The clinical management of patients with skeletal metastases puts new demands on imaging. The radiological imaging in screening for skeletal metastases entails detection, metastatic site description and radiologically guided biopsy for morphological typing and diagnosis. Regarding sensitivity and the ease in performing surveys of the whole skeleton, radionuclide bone scintigraphy still is the first choice in routine follow-up of asymptomatic patients with metastatic disease of the skeleton. A negative scan has to be re-evaluated with other findings, with emphasis on the possibility of a false-negative result. Screening for metastases in patients with local symptoms or pain is best accomplished by a combination of radiography and MRI. Water-weighted sequences are superior in sensitivity and in detection of metastases. Standard spin-echo sequences on the other hand are superior in metastatic site description and in detection of intraspinal metastases. MRI is helpful in differentiating between malignant disease, infection, benign vertebral collapse, insufficiency fracture after radiation therapy, degenerative vertebral disease and benign skeletal lesions. About 30% of patients with known cancer have benign causes of radiographic abnormalities. Most of these are related to degenerative diseases and are often easily diagnosed. However, due to overlap in MRI characteristics, bone biopsy sometimes is essential for differentiating between malignant and nonmalignant lesions. Performing bone biopsy and aspiration cytology by radiologist and cytologist in co-operation has proven highly accurate in diagnosing bone lesions. The procedure involves low risk to the patient and provides a morphological diagnosis. Once a suspected metastatic lesion is detected, irrespective of modality, the morphological diagnosis determines the appropriate work-up imaging with respect to the therapy alternatives. (orig./VHE)

Co-existent Paget’s Disease of the Bone, Prostate Carcinoma Skeletal Metastases and Fracture on Skeletal Scintigraphy-Lessons to be Learned

Directory of Open Access Journals (Sweden)

Luke I Sonoda

2013-08-01

Full Text Available Bone scintigraphy, despite being non-specific, is a very sensitive and simple investigation for patients with active Paget’s disease of the bone. Skeletal metastases and Paget’s disease may co-exist in the elderly patients as both conditions are commonly seen in this age group. Clinical and radiological correlation may help to improve the diagnostic specificity of a bone scintigram. We report a patient in whom concurrent Paget’s disease and a rib fracture became evident only on repeat scintigraphy following successful treatment of prostate carcinoma skeletal metastases.

Low-dose biplanar skeletal survey versus digital skeletal survey in multiple myeloma

International Nuclear Information System (INIS)

Boutry, Nathalie; Dutouquet, Bastien; Cotten, Anne; Leleu, Xavier; Vieillard, Marie-Helene; Duhamel, Alain

2013-01-01

To evaluate the low-dose biplanar (LDB) skeletal survey (SS) for the assessment of focal bone involvement in patients with multiple myeloma (MM) as compared with digital SS and to compare the two techniques in terms of image quality, patient comfort and radiation exposure. Fifty-six consecutive patients with newly diagnosed or first relapsed MM underwent LDB and digital SS on the same day. These were assessed by two radiologists for the detection of focal bone lesions. In the case of discordance, whole-body MR imaging was performed. Image quality, patient comfort and radiation dose were also assessed. Fifty-six patients (M:30, F:26, mean age, 62 years) with newly diagnosed (n = 21) or first relapse MM (n = 35) were enrolled. A total of 473 bone lesions in 46 patients (82 %) were detected. Out of that total, digital SS detected significantly more lesions than LDB SS (451 [95.35 %] versus 467 [98.73 %]), especially in osteopenic and obese patients. Overall patient satisfaction was greater with LDB SS (48.6 %) compared with digital SS (2.7 %). The radiation dose was significantly reduced (by a factor of 7.8) with the LDB X-ray device. Low-dose biplanar skeletal surveys cannot replace digital SS in all patients suffering from multiple myeloma. (orig.)

Low-dose biplanar skeletal survey versus digital skeletal survey in multiple myeloma

Energy Technology Data Exchange (ETDEWEB)

Boutry, Nathalie [University Hospital of Jeanne de Flandre and University of Lille 2, Departments of Pediatric and Musculoskeletal Imaging, Lille (France); University Hospital of Jeanne de Flandre and University of Lille 2, Department of Pediatric Imaging, Lille (France); Hopital Jeanne de Flandre, Service de Radiopediatrie, Lille (France); Dutouquet, Bastien; Cotten, Anne [University Hospital of Roger Salengro and University of Lille 2, Department of Musculoskeletal Imaging, Lille (France); Leleu, Xavier [University Hospital of Claude Huriez and University of Lille 2, Clinical Hematology Department, Lille (France); Vieillard, Marie-Helene [University Hospital of Roger Salengro and University of Lille 2, Rheumatology Department, Lille (France); Duhamel, Alain [University of Lille 2, Department of Medical Statistics, Lille (France)

2013-08-15

To evaluate the low-dose biplanar (LDB) skeletal survey (SS) for the assessment of focal bone involvement in patients with multiple myeloma (MM) as compared with digital SS and to compare the two techniques in terms of image quality, patient comfort and radiation exposure. Fifty-six consecutive patients with newly diagnosed or first relapsed MM underwent LDB and digital SS on the same day. These were assessed by two radiologists for the detection of focal bone lesions. In the case of discordance, whole-body MR imaging was performed. Image quality, patient comfort and radiation dose were also assessed. Fifty-six patients (M:30, F:26, mean age, 62 years) with newly diagnosed (n = 21) or first relapse MM (n = 35) were enrolled. A total of 473 bone lesions in 46 patients (82 %) were detected. Out of that total, digital SS detected significantly more lesions than LDB SS (451 [95.35 %] versus 467 [98.73 %]), especially in osteopenic and obese patients. Overall patient satisfaction was greater with LDB SS (48.6 %) compared with digital SS (2.7 %). The radiation dose was significantly reduced (by a factor of 7.8) with the LDB X-ray device. Low-dose biplanar skeletal surveys cannot replace digital SS in all patients suffering from multiple myeloma. (orig.)

ATP-induced changes in rat skeletal muscle contractility.

Science.gov (United States)

Gabdrakhmanov, A I; Khayrullin, A E; Grishin, C H; Ziganshin, A U

2015-01-01

considered as typical effects of ATP and other purines on skeletal muscles and could not be extrapolated to all warm-blooded animals. Furthermore the role of ATP and its derivatives in the accumulation of vertebrate muscular effort has not been investigated.It is known that in physiological conditions vertebrates may mobilize only up to a third of the maximum muscle force. Why the two-thirds of muscular strength are not used normally but may be used at stress, remains unknown.It is known that the body's adaptive response to stress is a change in the activity of the endocrine system. The leading role in this is given to catechol amines and glucocorticoids, mobilized in significant quantities in blood under stress.We have found previously that incubation of frog sartorius muscle with hydrocortisone resulted in a decrease of contraction amplitude. However, when hydrocortisone was used in combination with ATP, its inhibitory effect on contractile responses disappeared. It is interesting that hydrocortisone had no effect on the inhibitory effect of adenosine. In the following experiments, assessing the effect of hydrocortisone on rat soleus muscle, it was established that hydrocortisone and purines had similar inhibitory effect. When ATP and hydrocortisone were given together the same oppression occurred. To study the effects of ATP and adenosine on contraction parameters of rat skeletal muscle and assess the impact of the catechol amines on these processes. Contractions of rat soleus muscles were recorded isometrically by mechanical sensor Linton FSG-01 (UK) according to standard procedures. The average of muscle parameters received within 30 seconds (30 responses) was treated as one result. Amplitude and time characteristics of the curve reductions were estimated. During all experiments standard Krebs solution flowed through the bath continuously to which agents were added at necessary concentrations. All experimental animals were maintained and prepared for dissection under

Skeletal Dysplasias Associated with Mild Myopathy—A Clinical and Molecular Review

Directory of Open Access Journals (Sweden)

Katarzyna A. Piróg

2010-01-01

Full Text Available Musculoskeletal system is a complex assembly of tissues which acts as scaffold for the body and enables locomotion. It is often overlooked that different components of this system may biomechanically interact and affect each other. Skeletal dysplasias are diseases predominantly affecting the development of the osseous skeleton. However, in some cases skeletal dysplasia patients are referred to neuromuscular clinics prior to the correct skeletal diagnosis. The muscular complications seen in these cases are usually mild and may stem directly from the muscle defect and/or from the altered interactions between the individual components of the musculoskeletal system. A correct early diagnosis may enable better management of the patients and a better quality of life. This paper attempts to summarise the different components of the musculoskeletal system which are affected in skeletal dysplasias and lists several interesting examples of such diseases in order to enable better understanding of the complexity of human musculoskeletal system.

DNA Methylation in Skeletal Muscle Stem Cell Specification, Proliferation, and Differentiation

Directory of Open Access Journals (Sweden)

Rhianna C. Laker

2016-01-01

Full Text Available An unresolved and critically important question in skeletal muscle biology is how muscle stem cells initiate and regulate the genetic program during muscle development. Epigenetic dynamics are essential for cellular development and organogenesis in early life and it is becoming increasingly clear that epigenetic remodeling may also be responsible for the cellular adaptations that occur in later life. DNA methylation of cytosine bases within CpG dinucleotide pairs is an important epigenetic modification that reduces gene expression when located within a promoter or enhancer region. Recent advances in the field suggest that epigenetic regulation is essential for skeletal muscle stem cell identity and subsequent cell development. This review summarizes what is currently known about how skeletal muscle stem cells regulate the myogenic program through DNA methylation, discusses a novel role for metabolism in this process, and addresses DNA methylation dynamics in adult skeletal muscle in response to physical activity.

Obscurin Depletion Impairs Organization of Skeletal Muscle in Developing Zebrafish Embryos

Directory of Open Access Journals (Sweden)

Maide Ö. Raeker

2011-01-01

Full Text Available During development, skeletal myoblasts differentiate into myocytes and skeletal myotubes with mature contractile structures that are precisely oriented with respect to surrounding cells and tissues. Establishment of this highly ordered structure requires reciprocal interactions between the differentiating myocytes and the surrounding extracellular matrix to form correctly positioned and well-organized attachments from the skeletal muscle to the bony skeleton. Using the developing zebrafish embryo as a model, we examined the relationship between new myofibril assembly and the organization of the membrane domains involved in cell-extracellular matrix interactions. We determined that depletion of obscurin, a giant muscle protein, resulted in irregular cell morphology and disturbed extracellular matrix organization during skeletal muscle development. The resulting impairment of myocyte organization was associated with disturbance of the internal architecture of the myocyte suggesting that obscurin participates in organizing the internal structure of the myocyte and translating those structural cues to surrounding cells and tissues.

Obscurin Depletion Impairs Organization of Skeletal Muscle in Developing Zebrafish Embryos

Science.gov (United States)

Raeker, Maide Ö.; Russell, Mark W.

2011-01-01

During development, skeletal myoblasts differentiate into myocytes and skeletal myotubes with mature contractile structures that are precisely oriented with respect to surrounding cells and tissues. Establishment of this highly ordered structure requires reciprocal interactions between the differentiating myocytes and the surrounding extracellular matrix to form correctly positioned and well-organized attachments from the skeletal muscle to the bony skeleton. Using the developing zebrafish embryo as a model, we examined the relationship between new myofibril assembly and the organization of the membrane domains involved in cell-extracellular matrix interactions. We determined that depletion of obscurin, a giant muscle protein, resulted in irregular cell morphology and disturbed extracellular matrix organization during skeletal muscle development. The resulting impairment of myocyte organization was associated with disturbance of the internal architecture of the myocyte suggesting that obscurin participates in organizing the internal structure of the myocyte and translating those structural cues to surrounding cells and tissues. PMID:22190853

An image-based skeletal tissue model for the ICRP reference newborn

Energy Technology Data Exchange (ETDEWEB)

Pafundi, Deanna; Lee, Choonsik; Bolch, Wesley [Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, FL (United States); Watchman, Christopher; Bourke, Vincent [Department of Radiation Oncology, University of Arizona, Tucson, AZ (United States); Aris, John [Department of Anatomy and Cell Biology, University of Florida, Gainesville, FL (United States); Shagina, Natalia [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation); Harrison, John; Fell, Tim [Radiation Protection Division, Health Protection Agency, Chilton (United Kingdom)], E-mail: wbolch@ufl.edu

2009-07-21

Hybrid phantoms represent a third generation of computational models of human anatomy needed for dose assessment in both external and internal radiation exposures. Recently, we presented the first whole-body hybrid phantom of the ICRP reference newborn with a skeleton constructed from both non-uniform rational B-spline and polygon-mesh surfaces (Lee et al 2007 Phys. Med. Biol. 52 3309-33). The skeleton in that model included regions of cartilage and fibrous connective tissue, with the remainder given as a homogenous mixture of cortical and trabecular bone, active marrow and miscellaneous skeletal tissues. In the present study, we present a comprehensive skeletal tissue model of the ICRP reference newborn to permit a heterogeneous representation of the skeleton in that hybrid phantom set-both male and female-that explicitly includes a delineation of cortical bone so that marrow shielding effects are correctly modeled for low-energy photons incident upon the newborn skeleton. Data sources for the tissue model were threefold. First, skeletal site-dependent volumes of homogeneous bone were obtained from whole-cadaver CT image analyses. Second, selected newborn bone specimens were acquired at autopsy and subjected to micro-CT image analysis to derive model parameters of the marrow cavity and bone trabecular 3D microarchitecture. Third, data given in ICRP Publications 70 and 89 were selected to match reference values on total skeletal tissue mass. Active marrow distributions were found to be in reasonable agreement with those given previously by the ICRP. However, significant differences were seen in total skeletal and site-specific masses of trabecular and cortical bone between the current and ICRP newborn skeletal tissue models. The latter utilizes an age-independent ratio of 80%/20% cortical and trabecular bone for the reference newborn. In the current study, a ratio closer to 40%/60% is used based upon newborn CT and micro-CT skeletal image analyses. These changes in