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Sample records for striated shieldbug graphosoma

  1. Striated morphology during electrodeposition

    SciTech Connect

    Jorne, J.; Lee, M.G.

    1996-03-01

    Comparative study of striated morphologies obtained during the electrodeposition of various metals is performed using rotating electrodes. The formation of striation during electrodeposition of zinc, copper, and silver follows the streamlines of the fluid, and is observed to be accompanied by small or negative polarization resistance. The spacings between striae depends strongly on the applied current density. The spacing decreases with current density in the case of zinc and silver, however, a reverse trend is observed in the case of copper. Linear stability analysis shows that spatial multiplicity occurs when ({partial_derivative}i/{partial_derivative}C){sub {eta}} < 0. The experimentally observed spacings between striae (0.1 {approximately} 1 mm) are in agreement with the wavelength obtained from the linear stability analysis. The analysis of polarization and striation data shows fairly good qualitative agreement with respect to the effects of current density, diffusion layer thickness, and electrolyte concentration on striation.

  2. Gammaproteobacteria as essential primary symbionts in the striped shield bug, Graphosoma Lineatum (Hemiptera: Pentatomidae)

    PubMed Central

    Karamipour, Naeime; Mehrabadi, Mohammad; Fathipour, Yaghoub

    2016-01-01

    Many members of suborder Heteroptra harbor heritable symbiotic bacteria. Here we characterize the gut symbiotic bacterium in Graphosoma lineatum (Hemiptera: Pentatomidae) by using molecular phylogeny, real-time PCR analysis as well as light and electron microscopy observations. The microscopy observations revealed the presence of a large number of rod-shaped bacterial cells in the crypts. A very high prevalence (98 to 100%) of the symbiont infection was found in the insect populations that strongly supports an intimate association between these two organisms. Real-time PCR analysis also showed that the Gammaproteobacteria dominated the crypts. The sequences of 16sr RNA and groEL genes of symbiont showed high levels of similarity (93 to 95%) to Pantoea agglomeranse and Erwinia herbicola Gammaproteobacteria. Phylogenetic analyses placed G. lineatum symbiont in a well-defined branch, divergent from other stink bug bacterial symbionts. Co-evolutionary analysis showed lack of host-symbiont phylogenetic congruence. Surface sterilization of eggs resulted in increased pre-adult stage in the offspring (aposymbionts) in comparison to the normal. Also, fecundity, longevity, and adult stage were significantly decreased in the aposymbionts. Therefore, it seems that the symbiont might play a vital function in the host biology, in which host optimal development depends on the symbiont. PMID:27609055

  3. Gammaproteobacteria as essential primary symbionts in the striped shield bug, Graphosoma Lineatum (Hemiptera: Pentatomidae).

    PubMed

    Karamipour, Naeime; Mehrabadi, Mohammad; Fathipour, Yaghoub

    2016-01-01

    Many members of suborder Heteroptra harbor heritable symbiotic bacteria. Here we characterize the gut symbiotic bacterium in Graphosoma lineatum (Hemiptera: Pentatomidae) by using molecular phylogeny, real-time PCR analysis as well as light and electron microscopy observations. The microscopy observations revealed the presence of a large number of rod-shaped bacterial cells in the crypts. A very high prevalence (98 to 100%) of the symbiont infection was found in the insect populations that strongly supports an intimate association between these two organisms. Real-time PCR analysis also showed that the Gammaproteobacteria dominated the crypts. The sequences of 16sr RNA and groEL genes of symbiont showed high levels of similarity (93 to 95%) to Pantoea agglomeranse and Erwinia herbicola Gammaproteobacteria. Phylogenetic analyses placed G. lineatum symbiont in a well-defined branch, divergent from other stink bug bacterial symbionts. Co-evolutionary analysis showed lack of host-symbiont phylogenetic congruence. Surface sterilization of eggs resulted in increased pre-adult stage in the offspring (aposymbionts) in comparison to the normal. Also, fecundity, longevity, and adult stage were significantly decreased in the aposymbionts. Therefore, it seems that the symbiont might play a vital function in the host biology, in which host optimal development depends on the symbiont. PMID:27609055

  4. First record of Graphosoma inexpectatum (Hemiptera, Pentatomidae, Podopinae) from Turkey with description of the female

    PubMed Central

    Fent, Meral; Dursun, Ahmet; Tezcan, Serdar

    2013-01-01

    Abstract Graphosoma inexpectatum Carapezza & Jindra, 2008 is described from Syria, the southern neighbor of Turkey, and is known only from the type locality. The first observation of the species in Turkey dates back to 1995 with two females obtained from the provinces of Gaziantep (Şehitkamil–Aktoprak) and Adana (Pozantı–Bürücek Plateau). These two localities are situated inside the part of the Mediterranean region along the Syrian border. Females of the species, whose original description was based on males, are described here for the first time. A map showing the collecting localities and photographs of the female specimens are given. PMID:24039511

  5. Fine structure and chemical analysis of the metathoracic scent gland secretion in Graphosoma lineatum (Linnaeus, 1758) (Heteroptera, Pentatomidae).

    PubMed

    Durak, Dilek; Kalender, Yusuf

    2009-01-01

    Morphology and ultrastructure of metathoracic scent glands (MTGs) of Graphosoma lineatum (Heteroptera, Pentatomidae) were studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Extracts of the volatile fraction of the MTG secretion from males and females were subjected to initial analysis. One pair of the MTG is composed of a reservoir and a pair of lateral glands connected to the reservoir with a duct. MTGs are open in between the meso- and metacoxae, on evaporation areas with a mushroom-like structure. Reservoir walls embody two types of cells, type I and type II, respectively. Cells of type I have numerous organelles, while type II cells have only been found in a certain area of the reservoir wall. They have large secretory ducts lined by a cuticular intima layer. The lateral glands connected to reservoir have two further types of cells. Lateral glands are lined by type A secretory cells and secretory duct is found in their cytoplasm. Type B cells are poor in organelles and are smaller than type A cells. Coupled gas chromatography-mass spectrometry examinations revealed that both in males and females of G. lineatum MTGs 14 chemical compounds occur, among which only 10 are common. These secretions indicate information such as defensive and pheromonal activities, other functions could be attributed to the secretion of the MTG of G. lineatum by comparison with other closely related bug species. In the analyses of MTGs of females of G. lineatum, n-octadecanoic acid was observed at the most and n-undecane was determined at lowest level, while males of G. lineatum n-tridecane was determined at the highest level; and (E)-2-hexenyl acetate has been observed at the lowest. PMID:19200924

  6. Objective forensic analysis of striated, quasi-striated and impressed toolmarks

    NASA Astrophysics Data System (ADS)

    Spotts, Ryan E.

    Following the 1993 Daubert v. Merrell Dow Pharmaceuticals, Inc. court case and continuing to the 2010 National Academy of Sciences report, comparative forensic toolmark examination has received many challenges to its admissibility in court cases and its scientific foundations. Many of these challenges deal with the subjective nature in determining whether toolmarks are identifiable. This questioning of current identification methods has created a demand for objective methods of identification - "objective" implying known error rates and statistically reliability. The demand for objective methods has resulted in research that created a statistical algorithm capable of comparing toolmarks to determine their statistical similarity, and thus the ability to separate matching and nonmatching toolmarks. This was expanded to the creation of virtual toolmarking (characterization of a tool to predict the toolmark it will create). The statistical algorithm, originally designed for two-dimensional striated toolmarks, had been successfully applied to striated screwdriver and quasi-striated plier toolmarks. Following this success, a blind study was conducted to validate the virtual toolmarking capability using striated screwdriver marks created at various angles of incidence. Work was also performed to optimize the statistical algorithm by implementing means to ensure the algorithm operations were constrained to logical comparison regions (e.g. the opposite ends of two toolmarks do not need to be compared because they do not coincide with each other). This work was performed on quasi-striated shear cut marks made with pliers - a previously tested, more difficult application of the statistical algorithm that could demonstrate the difference in results due to optimization. The final research conducted was performed with pseudostriated impression toolmarks made with chisels. Impression marks, which are more complex than striated marks, were analyzed using the algorithm to separate

  7. Cone inputs to murine striate cortex

    PubMed Central

    Ekesten, Björn; Gouras, Peter

    2008-01-01

    Background We have recorded responses from single neurons in murine visual cortex to determine the effectiveness of the input from the two murine cone photoreceptor mechanisms and whether there is any unique selectivity for cone inputs at this higher region of the visual system that would support the possibility of colour vision in mice. Each eye was stimulated by diffuse light, either 370 (strong stimulus for the ultra-violet (UV) cone opsin) or 505 nm (exclusively stimulating the middle wavelength sensitive (M) cone opsin), obtained from light emitting diodes (LEDs) in the presence of a strong adapting light that suppressed the responses of rods. Results Single cells responded to these diffuse stimuli in all areas of striate cortex. Two types of responsive cells were encountered. One type (135/323 – 42%) had little to no spontaneous activity and responded at either the on and/or the off phase of the light stimulus with a few impulses often of relatively large amplitude. A second type (166/323 – 51%) had spontaneous activity and responded tonically to light stimuli with impulses often of small amplitude. Most of the cells responded similarly to both spectral stimuli. A few (18/323 – 6%) responded strongly or exclusively to one or the other spectral stimulus and rarely in a spectrally opponent manner. Conclusion Most cells in murine striate cortex receive excitatory inputs from both UV- and M-cones. A small fraction shows either strong selectivity for one or the other cone mechanism and occasionally cone opponent responses. Cells that could underlie chromatic contrast detection are present but extremely rare in murine striate cortex. PMID:19014590

  8. Collisionless Plasma Shocks in Striated Electron Temperatures

    SciTech Connect

    Guio, P.; Pecseli, H. L.

    2010-02-26

    The existence of low frequency waveguide modes of ion acoustic waves is demonstrated in magnetized plasmas for electron temperatures striated along the magnetic field lines. At higher frequencies, in a band between the ion cyclotron and the ion plasma frequency, radiative modes develop and propagate obliquely to the field away from the striation. Arguments for the subsequent formation and propagation of electrostatic shock are presented and demonstrated numerically. For such plasma conditions, the dissipation mechanism is the 'leakage' of the harmonics generated by the wave steepening.

  9. Independent evolution of striated muscles in cnidarians and bilaterians

    PubMed Central

    Steinmetz, Patrick R.H.; Kraus, Johanna E.M.; Larroux, Claire; U. Hammel, Jörg; Amon-Hassenzahl, Annette; Houliston, Evelyn; Wörheide, Gert; Nickel, Michael; Degnan, Bernard M.; Technau, Ulrich

    2012-01-01

    Striated muscles are present in bilaterian animals (e.g. vertebrates, insects, annelids) and some non-bilaterian eumetazoans (i.e. cnidarians and ctenophores). The striking ultrastructural similarity of striated muscles between these animal groups is thought to reflect a common evolutionary origin1, 2. Here we show that a muscle protein core set, including a Myosin type II Heavy Chain motor protein characteristic of striated muscles in vertebrates (MyHC-st), was already present in unicellular organisms before the origin of multicellular animals. Furthermore, myhc-st and myhc-non-muscle (myhc-nm) orthologues are expressed differentially in two sponges, compatible with the functional diversification of myhc paralogues before the origin of true muscles and the subsequent deployment of MyHC-st in fast-contracting smooth and striated muscle. Cnidarians and ctenophores possess myhc-st orthologues but lack crucial components of bilaterian striated muscles, such as troponin complex and titin genes, suggesting the convergent evolution of striated muscles. Consistently, jellyfish orthologues of a shared set of bilaterian z-disc proteins are not associated with striated muscles, but are instead expressed elsewhere or ubiquitously. The independent evolution of eumetazoan striated muscles through the addition of novel proteins to a pre-existing, ancestral contractile apparatus may serve as a paradigm for the evolution of complex animal cell types. PMID:22763458

  10. Interrelated striated elements in vestibular hair cells of the rat

    NASA Technical Reports Server (NTRS)

    Ross, M. D.; Bourne, C.

    1983-01-01

    A series of interrelated striated organelles in types I and II vestibular hair cells of the rat which appear to be less developed in cochlear hair cells have been revealed by unusual fixation procedures, suggesting that contractile elements may play a role in sensory transduction in the inner ear, especially in the vestibular system. Included in the series of interrelated striated elements are the cuticular plate and its basal attachments to the hair cell margins, the connections of the strut array of the kinociliary basal body to the cuticular plate, and striated organelles associated with the plasma membrane and extending below the apical junctional complexes.

  11. Representation of the visual field in the occipital striate cortex.

    PubMed Central

    McFadzean, R; Brosnahan, D; Hadley, D; Mutlukan, E

    1994-01-01

    The representation of the field of vision in the human striate cortex is based on the Holmes map in which about 25% of the surface area of the striate cortex is allocated to the central 15 degrees of vision. Following the introduction of computed tomography of the brain, the accuracy of the Holmes map was apparently confirmed by clinical/radiological correlation, but a revision has been proposed by Horton and Hoyt based on a magnetic resonance imaging study of three patients with visual field defects due to striate lesions. They propose that the central cortical representation of vision occupies a much larger area. This study reviews the perimetric and imaging findings in a larger series of patients with striate cortical disease and provides support for the revised representation. The clinical phenomenon of macular sparing and its relation to representation of the macula at the occipital pole is also discussed. Images PMID:8148333

  12. [Electron microscopic study of striate keratosis palmoplantaris (Wachters type)].

    PubMed

    Küchmeister, B; Mahrle, G

    1985-06-15

    We report on a patient suffering from striate palmoplantar keratoderma (Wachters' type). Ultrastructural findings are presented for the first time. There was orthohyperkeratosus without alterations indicating a specific disturbance of keratinisation. PMID:2411057

  13. An invertebrate smooth muscle with striated muscle myosin filaments

    PubMed Central

    Sulbarán, Guidenn; Alamo, Lorenzo; Pinto, Antonio; Márquez, Gustavo; Méndez, Franklin; Padrón, Raúl; Craig, Roger

    2015-01-01

    Muscle tissues are classically divided into two major types, depending on the presence or absence of striations. In striated muscles, the actin filaments are anchored at Z-lines and the myosin and actin filaments are in register, whereas in smooth muscles, the actin filaments are attached to dense bodies and the myosin and actin filaments are out of register. The structure of the filaments in smooth muscles is also different from that in striated muscles. Here we have studied the structure of myosin filaments from the smooth muscles of the human parasite Schistosoma mansoni. We find, surprisingly, that they are indistinguishable from those in an arthropod striated muscle. This structural similarity is supported by sequence comparison between the schistosome myosin II heavy chain and known striated muscle myosins. In contrast, the actin filaments of schistosomes are similar to those of smooth muscles, lacking troponin-dependent regulation. We conclude that schistosome muscles are hybrids, containing striated muscle-like myosin filaments and smooth muscle-like actin filaments in a smooth muscle architecture. This surprising finding has broad significance for understanding how muscles are built and how they evolved, and challenges the paradigm that smooth and striated muscles always have distinctly different components. PMID:26443857

  14. Subcellular distribution of potassium in striated muscles

    SciTech Connect

    Edelmann, L.

    1984-01-01

    Microanalytical experiments have been performed to answer the question whether the main cellular cation, K+, follows the water distribution in the striated muscle cell or whether K+ follows the distribution of negative fixed charges (beta- and gamma-carboxyl groups of aspartic and glutamic acid residues). Subcellular localization of K and/or of the K surrogates Rb, Cs, and Tl has been investigated by the following methods: Chemical precipitation of K with tetraphenylborate. Autoradiography of alkali-metals and Tl in air-dried and frozen-hydrated preparations. TEM visualization of electron dense Cs and Tl in sections of freeze-dried and plastic embedded muscle. X-ray microanalysis of air-dried myofibrils and muscle cryosections. The experiments consistently show that K, Rb, Cs, and Tl do not follow the water distribution but are mainly accumulated in the A band, especially in the marginal regions, and at Z lines. The same sites preferentially accumulate Cs or uranyl cations when sections of freeze-dried, embedded muscle are exposed to these electron microscopic stains. It is concluded that the detected uneven distribution of K, Rb, Cs, and Tl in muscle is neither a freeze-drying artifact nor an embedding artifact and may result from a weak ion binding to the beta- and gamma-carboxyl groups of cellular proteins.

  15. Poorly Understood Aspects of Striated Muscle Contraction

    PubMed Central

    Månsson, Alf

    2015-01-01

    Muscle contraction results from cyclic interactions between the contractile proteins myosin and actin, driven by the turnover of adenosine triphosphate (ATP). Despite intense studies, several molecular events in the contraction process are poorly understood, including the relationship between force-generation and phosphate-release in the ATP-turnover. Different aspects of the force-generating transition are reflected in the changes in tension development by muscle cells, myofibrils and single molecules upon changes in temperature, altered phosphate concentration, or length perturbations. It has been notoriously difficult to explain all these events within a given theoretical framework and to unequivocally correlate observed events with the atomic structures of the myosin motor. Other incompletely understood issues include the role of the two heads of myosin II and structural changes in the actin filaments as well as the importance of the three-dimensional order. We here review these issues in relation to controversies regarding basic physiological properties of striated muscle. We also briefly consider actomyosin mutation effects in cardiac and skeletal muscle function and the possibility to treat these defects by drugs. PMID:25961006

  16. Neurohypophyseal Hormones: Novel Actors of Striated Muscle Development and Homeostasis

    PubMed Central

    Costa, Alessandra; Rossi, Eleonora; Scicchitano, Bianca Maria; Coletti, Dario; Moresi, Viviana

    2014-01-01

    Since the 1980’s, novel functional roles of the neurohypophyseal hormones vasopressin and oxytocin have emerged. Several studies have investigated the effects of these two neurohormones on striated muscle tissues, both in vitro and in vivo. The effects of vasopressin on skeletal myogenic cells, developing muscle and muscle homeostasis have been documented. Oxytocin appears to have a greater influence on cardiomyocite differentiation and heart homeostasis. This review summarizes the studies on these novel roles of the two neurohypophyseal hormones, and open the possibility of new therapeutic approaches for diseases affecting striated muscle. PMID:26913138

  17. Extensive and intensive factors determining the performance of striated muscle.

    PubMed

    Josephson, R K

    1975-10-01

    Striated muscle is obviously a versatile tissue, one which has been malleable to selective pressure and has become modified for many specific tasks. The variations which adapt striated muscle to particular functions involve both changes in its structural organization and changes in the chemical nature of its components. Although a number of factors have been identified which contribute to the diversity of muscle performance, it is not yet possible to account adequately for the wide range in muscle performance throughout the animal kingdom. While not a new direction in comparative physiology, developing quantitative explanations for the diversity of muscle performance is still an obvious, remaining task. PMID:1104752

  18. Electromyography of the perineal striated muscles during cystometry.

    PubMed

    Vereecken, R L; Derluyn, J; Verduyn, H

    1975-01-01

    The electromyographic patterns of the external urethral sphincter, the anal sphincter, and the levator ani during cystometries have been analyzed. Synchronized activity changes occur during abdominal straining. Muscle fatigue is very pronounced. Activity may be less synchronized during bladder filling and micturition, even in normal cystometries. In neurogenic diseases, true dyssynergia between the striated muscles may be observed. PMID:1118953

  19. Voltage-dependent sodium channels in an invertebrate striated muscle.

    PubMed

    Schwartz, L M; Stühmer, W

    1984-08-01

    Striated skeletal muscles from the planktonic arrowworm Sagitta elegans (phylum Chaetognatha) were voltage-clamped. The muscles displayed classical voltage-dependent sodium channels that (i) showed peak transient currents when the membrane was depolarized 90 millivolts from rest, (ii) opened rapidly with peak currents flowing within 0.4 milliseconds at 4 degrees C, (iii) showed voltage-dependent inactivation with 50 percent inactivation at +25 millivolts from rest, and (iv) were blocked by 500 nanomolar tetrodotoxin. PMID:6330898

  20. Psychophysics of electrical stimulation of striate cortex in macaques.

    PubMed

    Bartlett, John R; DeYoe, Edgar A; Doty, Robert W; Lee, Barry B; Lewine, Jeffrey D; Negrão, Nubio; Overman, William H

    2005-11-01

    Macaques indicated their detection of onset or alteration of 0.2-ms pulses applied in various configurations through electrodes implanted in striate cortex. When microelectrodes were introduced and left in place, the threshold for detection of 100-Hz pulses nearly doubled within 24 h. However, for chronically implanted platinum-alloy macroelectrodes detection thresholds usually remained stable for many months, independently of location within striate cortex or its immediately subjacent white matter. Thresholds were unaffected by the visual conditions, such as light versus darkness, or movement of the eyes; but in one animal blind after acute glaucoma thresholds for loci in striate cortex were permanently decreased by about 50%. Learning to respond to electrical stimulation of the optic tract produced no tendency to respond to such stimulation of striate cortex. Onset of stimulation at a given locus could be detected even in the face of continuous supraliminal stimulation at four surrounding loci on a 3-mm radius. The surround stimulation did alter the threshold of the central locus, but such stimuli could not summate if they were subliminal by some 10%. Cessation of stimulation that had been continuing for 1 min to 1 h could be detected if it were being applied at a level 20-75% above that needed for detection of stimulus onset. Continuous stimulation had a pronounced "priming" effect, in that modulation of frequency or intensity of such stimulation by as little as 5% could be detected (e.g., 20 microA in a background of 500 microA, or <2-ms interpulse interval with pulses at 50 Hz). Using pulses inserted in various phase relations to ongoing pulses at 2-5 Hz, it could be determined that stimulus pulses were surrounded by a strong facilitatory period for about 30 ms, which was then replaced by refractoriness. Given the congruence of macaque and human visual anatomy and psychophysics, these results further encourage efforts to develop a cortical prosthesis for the

  1. Clinical and Experimental Pancreatic Islet Transplantation to Striated Muscle

    PubMed Central

    Christoffersson, Gustaf; Henriksnäs, Johanna; Johansson, Lars; Rolny, Charlotte; Ahlström, Håkan; Caballero-Corbalan, José; Segersvärd, Ralf; Permert, Johan; Korsgren, Olle; Carlsson, Per-Ola; Phillipson, Mia

    2010-01-01

    OBJECTIVE Curing type 1 diabetes by transplanting pancreatic islets into the liver is associated with poor long-term outcome and graft failure at least partly due to inadequate graft revascularization. The aim of the current study was to evaluate striated muscle as a potential angiogenic site for islet transplantation. RESEARCH DESIGN AND METHODS The current study presents a new experimental model that is found to be applicable to clinical islet transplantation. Islets were implanted into striated muscle and intraislet vascular density and blood flow were visualized with intravital and confocal microscopy in mice and by magnetic resonance imaging in three autotransplanted pancreatectomized patients. Mice were rendered neutropenic by repeated injections of Gr-1 antibody, and diabetes was induced by alloxan treatment. RESULTS Contrary to liver-engrafted islets, islets transplanted to mouse muscle were revascularized with vessel densities and blood flow entirely comparable with those of islets within intact pancreas. Initiation of islet revascularization at the muscular site was dependent on neutrophils, and the function of islets transplanted to muscle was proven by curing diabetic mice. The experimental data were confirmed in autotransplanted patients where higher plasma volumes were measured in islets engrafted in forearm muscle compared with adjacent muscle tissue through high-resolution magnetic resonance imaging. CONCLUSIONS This study presents a novel paradigm in islet transplantation whereby recruited neutrophils are crucial for the functionally restored intraislet blood perfusion following transplantation to striated muscle under experimental and clinical situations. PMID:20651296

  2. Deoxyglucose Analysis of Retinotopic Organization in Primate Striate Cortex

    NASA Astrophysics Data System (ADS)

    Tootell, Roger B. H.; Silverman, Martin S.; Switkes, Eugene; de Valois, Russell L.

    1982-11-01

    We have anatomically analyzed retinotopic organization using the 14C-labeled 2-deoxy-D-glucose method. The method has several advantages over conventional electrophysiological mapping techniques. In the striate cortex, the anatomical substrate for retinotopic organization is suprisingly well ordered, and there seems to be a systematic relationship between ocular dominance strips and cortical magnification. The 2-deoxyglucose maps in this area appear to be largely uninfluenced by known differences in long-term metabolic activity. This method should prove useful in analyzing retinotopic organization in various visual areas of the brain and in different species.

  3. Enrichment and terminal differentiation of striated muscle progenitors in vitro

    SciTech Connect

    Becher, Ulrich M.; Breitbach, Martin; Sasse, Philipp; Garbe, Stephan; Ven, Peter F.M. van der; Fuerst, Dieter O.; Fleischmann, Bernd K.

    2009-10-01

    Enrichment and terminal differentiation of mammalian striated muscle cells is severely hampered by fibroblast overgrowth, de-differentiation and/or lack of functional differentiation. Herein we report a new, reproducible and simple method to enrich and terminally differentiate muscle stem cells and progenitors from mice and humans. We show that a single gamma irradiation of muscle cells induces their massive differentiation into structurally and functionally intact myotubes and cardiomyocytes and that these cells can be kept in culture for many weeks. Similar results are also obtained when treating skeletal muscle-derived stem cells and progenitors with Mitomycin C.

  4. Allergic Interstitial Nephritis Manifesting as a Striated Nephrogram

    PubMed Central

    Moinuddin, Irfan; Bracamonte, Erika; Thajudeen, Bijin; Sussman, Amy; Madhrira, Machaiah; Costello, James

    2015-01-01

    Allergic interstitial nephritis (AIN) is an underdiagnosed cause of acute kidney injury (AKI). Guidelines suggest that AIN should be suspected in a patient who presents with an elevated serum creatinine and a urinalysis that shows white cells, white cell casts, or eosinophiluria. Drug-induced AIN is suspected if AKI is temporally related to the initiation of a new drug. However, patients with bland sediment and normal urinalysis can also have AIN. Currently, a definitive diagnosis of AIN is made by renal biopsy which is invasive and fraught with risks such as bleeding, infection, and hematoma. Additionally, it is frequently unclear when a kidney biopsy should be undertaken. We describe a biopsy proven case of allergic interstitial nephritis which manifested on contrast enhanced Magnetic Resonance Imaging (MRI) as a striated nephrogram. Newer and more stable macrocyclic gadolinium contrast agents have a well-demonstrated safety profile. Additionally, in the presentation of AKI, gadolinium contrast agents are safe to administer in patients who demonstrate good urine output and a downtrending creatinine. We propose that the differential for a striated nephrogram may include AIN. In cases in which the suspicion for AIN is high, this diagnostic consideration may be further characterized by contrast enhanced MRI. PMID:26664405

  5. Virtual and simulated striated toolmarks for forensic applications.

    PubMed

    Baiker, Martin; Petraco, Nicholas D K; Gambino, Carol; Pieterman, René; Shenkin, Peter; Zoon, Peter

    2016-04-01

    Large numbers of experimental toolmarks of screwdrivers are often required in casework of toolmark examiners and in research environments alike, to be able to recover the angle of attack of a crime scene mark and to determine statistically meaningful properties of toolmarks respectively. However, in practice the number of marks is limited by the time needed to create them. In this article, we present an approach to predict how a striated mark of a particular tool would look like, using 3D surface datasets of screwdrivers. We compare these virtual toolmarks qualitatively and quantitatively with real experimental marks in wax and show that they are very similar. In addition we study toolmark similarity, dependent on the angle of attack, with a very high angular resolution of 1°. The results show that for the tested type of screwdriver, our toolmark comparison framework yields known match similarity scores that are above the mean known non-match similarity scores, even for known match differences in angle of attack of up to 40°. In addition we demonstrate an approach to automatically recover the angle of attack of an experimental toolmark and experiments yield high accuracy and precision of 0.618 ± 4.179°. Furthermore, we present a strategy to study the structural elements of striated toolmarks using wavelet analysis, and show how to use the results to simulate realistic toolmarks. PMID:26874738

  6. Weakly nonlinear ion waves in striated electron temperatures

    NASA Astrophysics Data System (ADS)

    Guio, P.; Pécseli, H. L.

    2016-04-01

    The existence of low-frequency waveguide modes of electrostatic ion acoustic waves is demonstrated in magnetized plasmas for cases where the electron temperature is striated along magnetic field lines. For low frequencies, the temperature striation acts as waveguide that supports a trapped mode. For conditions where the ion cyclotron frequency is below the ion plasma frequency we find a dispersion relation having also a radiative frequency band, where waves can escape from the striation. Arguments for the formation and propagation of an equivalent of electrostatic shocks are presented and demonstrated numerically for these conditions. The shock represents here a balance between an external energy input maintained by ion injection and a dissipation mechanism in the form of energy leakage of the harmonics generated by nonlinear wave steepening. This is a reversible form for energy loss that can replace the time-irreversible losses in a standard Burgers equation.

  7. Degree of polarization of light diffracted from resting striated muscle.

    PubMed

    Leung, A F

    1987-04-01

    A laser light diffractometer has been developed to measure directly the total degree of polarization of (alpha t) of light diffracted and randomly scattered from striated muscle fibers. From alpha t the degree of polarization (alpha d) of light diffracted from the periodically arranged contractile filaments is determined. Measurements on single muscle fibers and small fiber bundles indicate that both alpha t and alpha d of the first-order diffraction decrease monotonically with sarcomere length. For the second-order diffraction, alpha t and alpha d exhibit a peak at sarcomere length of about 3.0 micron. A proposed theory based on the anisotropic light scattering efficiencies of the thick and thin filaments can account for the measurements. The comparison between the theory and measurements indicates that the A-band, as well as the I-band, are optically anisotropic. PMID:2443248

  8. The Chromatin Remodeling Complex Chd4/NuRD Controls Striated Muscle Identity and Metabolic Homeostasis.

    PubMed

    Gómez-Del Arco, Pablo; Perdiguero, Eusebio; Yunes-Leites, Paula Sofia; Acín-Pérez, Rebeca; Zeini, Miriam; Garcia-Gomez, Antonio; Sreenivasan, Krishnamoorthy; Jiménez-Alcázar, Miguel; Segalés, Jessica; López-Maderuelo, Dolores; Ornés, Beatriz; Jiménez-Borreguero, Luis Jesús; D'Amato, Gaetano; Enshell-Seijffers, David; Morgan, Bruce; Georgopoulos, Katia; Islam, Abul B M M K; Braun, Thomas; de la Pompa, José Luis; Kim, Johnny; Enriquez, José A; Ballestar, Esteban; Muñoz-Cánoves, Pura; Redondo, Juan Miguel

    2016-05-10

    Heart muscle maintains blood circulation, while skeletal muscle powers skeletal movement. Despite having similar myofibrilar sarcomeric structures, these striated muscles differentially express specific sarcomere components to meet their distinct contractile requirements. The mechanism responsible is still unclear. We show here that preservation of the identity of the two striated muscle types depends on epigenetic repression of the alternate lineage gene program by the chromatin remodeling complex Chd4/NuRD. Loss of Chd4 in the heart triggers aberrant expression of the skeletal muscle program, causing severe cardiomyopathy and sudden death. Conversely, genetic depletion of Chd4 in skeletal muscle causes inappropriate expression of cardiac genes and myopathy. In both striated tissues, mitochondrial function was also dependent on the Chd4/NuRD complex. We conclude that an epigenetic mechanism controls cardiac and skeletal muscle structural and metabolic identities and that loss of this regulation leads to hybrid striated muscle tissues incompatible with life. PMID:27166947

  9. X-ray Diffraction Studies of Striated Muscles

    SciTech Connect

    Squire, J.M.; Knupp, C.; Roessle, M.; Al-Khayat, H.A.; Irving, T.C.; Eakins, F.; Mok, N.-S.; Harford, J.J.; Reedy, M.K.

    2006-04-24

    In this short review a number of recent X-ray diffraction results on the highly ordered striated muscles in insects and in bony fish have been briefly described. What is clear is that this technique applied to muscles which are amenable to rigorous analysis, taken together with related data from other sources (e.g. protein crystallography, biochemistry, mechanics, computer modelling) can provide not only the best descriptions yet available on the myosin head organisations on different myosin filaments in the relaxed state, but can also show the sequence of molecular events that occurs in the contractile cycle, and may also help to explain such phenomena as stretch-activation. X-ray diffraction is clearly an enormously powerful tool in studies of muscle. It has already provided a wealth of detail on muscle ultrastructure; it is providing ever more fascinating insights into molecular events in the 50-year old sliding filament mechanism, and there remains a great deal more potential that is as yet untapped.

  10. Spatially congruent model for the striate visual cortex

    NASA Astrophysics Data System (ADS)

    da Fontoura Costa, Luciano

    1994-05-01

    A spatially congruent new model for the striate visual cortex (SVC) is proposed which accounts for some of the known functional and organizational properties of the superior mammalian SVC. Even though there is a broad consensus that the topographical representation of the visual field is one of the principal structuring principles underlying the SVC organization, the orientation maps in the SVC have often been described as non-topographical maps. In the present model, the adopted foot-of-normal representation of straight lines has allowed full congruency between the visual field topographic map and the orientation maps in the SVC. The proposed computational model includes three neural layers and assumes that the ocular dominance columns are already established at birth; three possibilities of neural mechanisms leading to orientation encoding are outlined and discussed. The model provides reasonable explanation to some of the most intriguing recently verified properties of the SVC such as the increased neural activity at the cytochrome oxidase blobs, the reduced orientation selectivity at these same places, and the pinwheel-like organization of the orientation selectivity in the SVC.

  11. Neuronal basis of perceptual learning in striate cortex

    PubMed Central

    Ren, Zhen; Zhou, Jiawei; Yao, Zhimo; Wang, Zhengchun; Yuan, Nini; Xu, Guangwei; Wang, Xuan; Zhang, Bing; Hess, Robert F.; Zhou, Yifeng

    2016-01-01

    It is well known that, in humans, contrast sensitivity training at high spatial frequency (SF) not only leads to contrast sensitivity improvement, but also results in an improvement in visual acuity as assessed with gratings (direct effect) or letters (transfer effect). However, the underlying neural mechanisms of this high spatial frequency training improvement remain to be elucidated. In the present study, we examined four properties of neurons in primary visual cortex (area 17) of adult cats that exhibited significantly improved acuity after contrast sensitivity training with a high spatial frequency grating and those of untrained control cats. We found no difference in neuronal contrast sensitivity or tuning width (Width) between the trained and untrained cats. However, the trained cats showed a displacement of the cells’ optimal spatial frequency (OSF) to higher spatial frequencies as well as a larger neuronal signal-to-noise ratio (SNR). Furthermore, both the neuronal differences in OSF and SNR were significantly correlated with the improvement of acuity measured behaviorally. These results suggest that striate neurons might mediate the perceptual learning-induced improvement for high spatial frequency stimuli by an alteration in their spatial frequency representation and by an increased SNR. PMID:27094565

  12. Receptive fields of simple cells in the cat striate cortex

    PubMed Central

    Bishop, P. O.; Coombs, J. S.; Henry, G. H.

    1973-01-01

    1. The excitatory and inhibitory components in the receptive fields of unimodal simple cells in the striate cortex of the cat anaesthetized with nitrous oxide have been described using slits of light and single light-dark edges as stimuli. 2. There is a small excitatory region (excitatory complex) centrally located in the receptive field that is made up of various combinations and spatial arrangements of subliminal excitatory and discharge subregions or centres. 3. The subliminal excitatory centres were revealed by a binocular facilitation technique. The excitability of the cell was raised by repeated stimulation via one eye while the neurone was tested with single edges via the other eye. 4. The subliminal excitatory and discharge centres are each specifically activated by only one type of edge, light-dark or dark-light, and then only in one direction of motion. All the subregions in the excitatory complex have the same optimal stimulus orientation. 5. Inhibitory components in the receptive field were identified by stimulating the cell with bars of light and single edges against an artificial background discharge produced by repeated stimulation separately applied either to the same eye (monocular conditioning) or to the other eye (binocular conditioning). There are powerful inhibitory sidebands to either side of the excitatory complex and these inhibitory regions merge to include the excitatory complex when stimulus orientation is angled away from the optimal. 6. Excitation is highly stimulus specific whereas inhibition is non-specific. 7. The organization of the two receptive fields of a binocularly discharged cell can be closely similar. 8. The attempt is made to translate the concept of subliminal excitatory and discharge centres into specific neural mechanisms involving both the geniculo-cortical input and various intracortical circuits. 9. These new developments call for only minor modifications to the model we have proposed for the organization of the

  13. Orientation selectivity, preference, and continuity in monkey striate cortex.

    PubMed

    Blasdel, G G

    1992-08-01

    Maps of orientation preference and selectivity, inferred from differential images of orientation (Blasdel, 1992), reveal linear organizations in patches, 0.5-1.0 mm across, where orientation selectivities are high, and where preferred orientations rotate linearly along one axis while remaining constant along the other. Most of these linear zones lie between the centers of adjacent ocular dominance columns, with their short iso-orientation slabs oriented perpendicular, in regions enjoying the greatest binocular overlap. These two-dimensional linear zones are segregated by one- and zero-dimensional discontinuities that are particularly abundant in the centers of ocular dominance columns, and that are also correlated with cytochrome oxidase-rich zones within them. Discontinuities smaller than 90 degrees extend in one dimension, as fractures, while discontinuities greater than 90 degrees are confined to points, in the form of singularities, that are generated when orientation preferences rotate continuously through +/- 180 degrees along circular paths. The continuous rotations through 180 degrees imply that direction preferences are not organized laterally in striate cortex. And they also ensure that preferences for all orientations converge at each singularity, with perpendicular orientations represented uniquely close together on opposite sides. The periodic interspersing of linear zones and singularities suggests that orientation preferences are organized by at least two competing schemes. They are optimized for linearity, along with selectivity and binocularity, in the linear zones, and they are optimized for density near singularities. Since upper-layer neurons are likely to have similarly sized dendritic fields in all regions (Lund and Yoshioka, 1991), those in the linear zones should receive precise information about narrowly constrained orientations, while those near singularities should receive coarse information about all orientations--very different inputs

  14. The striated muscles in pulmonary arterial hypertension: adaptations beyond the right ventricle.

    PubMed

    Manders, Emmy; Rain, Silvia; Bogaard, Harm-Jan; Handoko, M Louis; Stienen, Ger J M; Vonk-Noordegraaf, Anton; Ottenheijm, Coen A C; de Man, Frances S

    2015-09-01

    Pulmonary arterial hypertension (PAH) is a fatal lung disease characterised by progressive remodelling of the small pulmonary vessels. The daily-life activities of patients with PAH are severely limited by exertional fatigue and dyspnoea. Typically, these symptoms have been explained by right heart failure. However, an increasing number of studies reveal that the impact of the PAH reaches further than the pulmonary circulation. Striated muscles other than the right ventricle are affected in PAH, such as the left ventricle, the diaphragm and peripheral skeletal muscles. Alterations in these striated muscles are associated with exercise intolerance and reduced quality of life. In this Back to Basics article on striated muscle function in PAH, we provide insight into the pathophysiological mechanisms causing muscle dysfunction in PAH and discuss potential new therapeutic strategies to restore muscle dysfunction. PMID:26113677

  15. Use of flow, electrical, and mechanical stimulation to promote engineering of striated muscles

    PubMed Central

    Rangarajan, Swathi; Madden, Lauran; Bursac, Nenad

    2014-01-01

    The field of tissue engineering involves design of high-fidelity tissue substitutes for predictive experimental assays in vitro and cell-based regenerative therapies in vivo. Design of striated muscle tissues, such as cardiac and skeletal muscle, has been particularly challenging due to a high metabolic demand and complex cellular organization and electromechanical function of the native tissues. Successful engineering of highly functional striated muscles may thus require creation of biomimetic culture conditions involving medium perfusion, electrical and mechanical stimulation. When optimized, these external cues are expected to synergistically and dynamically activate important intracellular signaling pathways leading to accelerated muscle growth and development. This review will discuss the use of different types of tissue culture bioreactors aimed at providing conditions for enhanced structural and functional maturation of engineered striated muscles. PMID:24366526

  16. Two rules for callosal connectivity in striate cortex of the rat.

    PubMed

    Lewis, J W; Olavarria, J F

    1995-10-01

    In the rat, callosal cells occupy lateral as well as medial portions of striate cortex. In the region of the border between areas 17 and 18, which contains a representation of the vertical meridian of the visual field, cells projecting through the corpus callosum are concentrated throughout the depth of the cortex. In contrast, in medial portion of striate cortex, where peripheral portions of the visual field are represented, callosal cells are preferentially found in infragranular layers. These differences in topography and laminar distribution suggest that these callosal regions, referred to as medial and lateral callosal regions in the present study, subserve different functions. We explored this possibility by analyzing the patterns of callosal linkages in these two callosal regions. We charted the location of retrogradely labeled cells within striate cortex of one hemisphere after placing restricted injections of one or more fluorescent tracers into selected sites in the contralateral striate cortex. We found the medial and lateral callosal regions have distinctly different topographic organizations. Injections into medial striate cortex of one hemisphere produced labeled cells predominantly in mirror-symmetric loci in medial portions of contralateral striate cortex. The arrangement of these connections suggests that they mediate direct interactions between cortical regions representing visual fields located symmetrically on opposite sides of the vertical meridian of the visual field. In contrast, the mapping in the lateral callosal region is reversed: injections into the 17/18a border produced labeled fields located medial to the contralateral 17/18a border, while injections slightly medial to the 17/18a border produced labeled fields located at the contralateral 17/18a border.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8550874

  17. Striated boulder pavements within glaciomarine diamicts of the Yakataga Formation, Middleton Island, Alaska

    SciTech Connect

    Eyles, C.H.

    1985-01-01

    The presence of striated boulder pavements in glacial sequences is often cited as evidence of transport and deposition by grounded glacier ice. However, recent reports show that striated pavements also form in non-glacial environments by the abrasion of boulder lag surfaces by floating glacier and seasonal ice. Several striated boulder pavements are identified within Early Pleistocene upper Yakataga Formation sediments exposed on Middleton Island close to the southern edge of the Gulf of Alaska continental shelf. The sequence is dominated by thick stratiform units of massive and stratified diamict formed by the settling of fine-grained sands and muds from suspension together with ice-rafted debris. Boulder pavements outcrop as extensive planar horizons within the diamicts, can be traced for several kilometers along strike and consist of single lines of clasts with faceted upper surfaces showing consistently oriented striation directions. Clasts are not preferentially aligned, however, and do not have the characteristic bullet shape of boulders transported at a glacier base and deposited by lodgement processes. Striated boulder pavements on Middleton Island appear to have formed as boulder lag surfaces generated by wave and tidal current reworking of diamict on relatively shallow banks. Lags were then overridden and abraded by a grounding ice shelf. The glacially-abraded boulder pavements on Middleton Island record the repeated expansion of a continuous ice shelf to the edge of the Gulf of Alaska continental shelf during the Early Pleistocene.

  18. Embracing change: striated-for-smooth muscle replacement in esophagus development.

    PubMed

    Krauss, Robert S; Chihara, Daisuke; Romer, Anthony I

    2016-01-01

    The esophagus functions to transport food from the oropharyngeal region to the stomach via waves of peristalsis and transient relaxation of the lower esophageal sphincter. The gastrointestinal tract, including the esophagus, is ensheathed by the muscularis externa (ME). However, while the ME of the gastrointestinal tract distal to the esophagus is exclusively smooth muscle, the esophageal ME of many vertebrate species comprises a variable amount of striated muscle. The esophageal ME is initially composed only of smooth muscle, but its developmental maturation involves proximal-to-distal replacement of smooth muscle with striated muscle. This fascinating phenomenon raises two important questions: what is the developmental origin of the striated muscle precursor cells, and what are the cellular and morphogenetic mechanisms underlying the process? Studies addressing these questions have provided controversial answers. In this review, we discuss the development of ideas in this area and recent work that has shed light on these issues. A working model has emerged that should permit deeper understanding of the role of ME development and maturation in esophageal disorders and in the functional and evolutionary underpinnings of the variable degree of esophageal striated myogenesis in vertebrate species. PMID:27504178

  19. Ultrastructure of geniculocortical synaptic connections in the tree shrew striate cortex.

    PubMed

    Familtsev, Dmitry; Quiggins, Ranida; Masterson, Sean P; Dang, Wenhao; Slusarczyk, Arkadiusz S; Petry, Heywood M; Bickford, Martha E

    2016-04-15

    To determine whether thalamocortical synaptic circuits differ across cortical areas, we examined the ultrastructure of geniculocortical terminals in the tree shrew striate cortex to compare directly the characteristics of these terminals with those of pulvinocortical terminals (examined previously in the temporal cortex of the same species; Chomsung et al. [] Cereb Cortex 20:997-1011). Tree shrews are considered to represent a prototype of early prosimian primates but are unique in that sublaminae of striate cortex layer IV respond preferentially to light onset (IVa) or offset (IVb). We examined geniculocortical inputs to these two sublayers labeled by tracer or virus injections or an antibody against the type 2 vesicular glutamate antibody (vGLUT2). We found that layer IV geniculocortical terminals, as well as their postsynaptic targets, were significantly larger than pulvinocortical terminals and their postsynaptic targets. In addition, we found that 9-10% of geniculocortical terminals in each sublamina contacted GABAergic interneurons, whereas pulvinocortical terminals were not found to contact any interneurons. Moreover, we found that the majority of geniculocortical terminals in both IVa and IVb contained dendritic protrusions, whereas pulvinocortical terminals do not contain these structures. Finally, we found that synaptopodin, a protein uniquely associated with the spine apparatus, and telencephalin (TLCN, or intercellular adhesion molecule type 5), a protein associated with maturation of dendritic spines, are largely excluded from geniculocortical recipient layers of the striate cortex. Together our results suggest major differences in the synaptic organization of thalamocortical pathways in striate and extrastriate areas. PMID:26399201

  20. Non-conscious recognition of affect in the absence of striate cortex.

    PubMed

    de Gelder, B; Vroomen, J; Pourtois, G; Weiskrantz, L

    1999-12-16

    Functional neuroimaging experiments have shown that recognition of emotional expressions does not depend on awareness of visual stimuli and that unseen fear stimuli can activate the amygdala via a colliculopulvinar pathway. Perception of emotional expressions in the absence of awareness in normal subjects has some similarities with the unconscious recognition of visual stimuli which is well documented in patients with striate cortex lesions (blindsight). Presumably in these patients residual vision engages alternative extra-striate routes such as the superior colliculus and pulvinar. Against this background, we conjectured that a blindsight subject (GY) might recognize facial expressions presented in his blind field. The present study now provides direct evidence for this claim. PMID:10716205

  1. Z-line formins promote contractile lattice growth and maintenance in striated muscles of C. elegans

    PubMed Central

    Mi-Mi, Lei; Votra, SarahBeth; Kemphues, Kenneth; Bretscher, Anthony

    2012-01-01

    Muscle contraction depends on interactions between actin and myosin filaments organized into sarcomeres, but the mechanism by which actin filaments incorporate into sarcomeres remains unclear. We have found that, during larval development in Caenorhabditis elegans, two members of the actin-assembling formin family, CYK-1 and FHOD-1, are present in striated body wall muscles near or on sarcomere Z lines, where barbed ends of actin filaments are anchored. Depletion of either formin during this period stunted growth of the striated contractile lattice, whereas their simultaneous reduction profoundly diminished lattice size and number of striations per muscle cell. CYK-1 persisted at Z lines in adulthood, and its near complete depletion from adults triggered phenotypes ranging from partial loss of Z line–associated filamentous actin to collapse of the contractile lattice. These results are, to our knowledge, the first genetic evidence implicating sarcomere-associated formins in the in vivo organization of the muscle cytoskeleton. PMID:22753896

  2. Role of retinal input on the development of striate-extrastriate patterns of connections in the rat.

    PubMed

    Laing, R J; Bock, A S; Lasiene, J; Olavarria, J F

    2012-10-01

    Previous studies have shown that retinal input plays an important role in the development of interhemispheric callosal connections, but little is known about the role retinal input plays on the development of ipsilateral striate-extrastriate connections and the interplay that might exist between developing ipsilateral and callosal pathways. We analyzed the effects of bilateral enucleation performed at different ages on both the distribution of extrastriate projections originating from restricted loci in medial, acallosal striate cortex, and the overall pattern of callosal connections revealed following multiple tracer injections. As in normal rats, striate-extrastriate projections in rats enucleated at birth consisted of multiple, well-defined fields that were largely confined to acallosal regions throughout extrastriate cortex. However, these projections were highly irregular and variable, and they tended to occupy correspondingly anomalous and variable acallosal regions. Moreover, area 17, but not area 18a, was smaller in enucleates compared to controls, resulting in an increase in the divergence of striate projections. Anomalies in patterns of striate-extrastriate projections were not observed in rats enucleated at postnatal day (P)6, although the size of area 17 was still reduced in these rats. These results indicate that the critical period during which the eyes influence the development of striate-extrastriate, but not the size of striate cortex, ends by P6. Finally, enucleation did not change the time course and definition of the initial invasion of axons into gray matter, suggesting that highly variable striate projections patterns do not result from anomalous pruning of exuberant distributions of 17-18a fibers in gray matter. PMID:22430936

  3. Segregation of striated and smooth muscle lineages by a Notch-dependent regulatory network

    PubMed Central

    2014-01-01

    Background Lineage segregation from multipotent epithelia is a central theme in development and in adult stem cell plasticity. Previously, we demonstrated that striated and smooth muscle cells share a common progenitor within their epithelium of origin, the lateral domain of the somite-derived dermomyotome. However, what controls the segregation of these muscle subtypes remains unknown. We use this in vivo bifurcation of fates as an experimental model to uncover the underlying mechanisms of lineage diversification from bipotent progenitors. Results Using the strength of spatio-temporally controlled gene missexpression in avian embryos, we report that Notch harbors distinct pro-smooth muscle activities depending on the duration of the signal; short periods prevent striated muscle development and extended periods, through Snail1, promote cell emigration from the dermomyotome towards a smooth muscle fate. Furthermore, we define a Muscle Regulatory Network, consisting of Id2, Id3, FoxC2 and Snail1, which acts in concert to promote smooth muscle by antagonizing the pro-myogenic activities of Myf5 and Pax7, which induce striated muscle fate. Notch and BMP closely regulate the network and reciprocally reinforce each other’s signal. In turn, components of the network strengthen Notch signaling, while Pax7 silences this signaling. These feedbacks augment the robustness and flexibility of the network regulating muscle subtype segregation. Conclusions Our results demarcate the details of the Muscle Regulatory Network, underlying the segregation of muscle sublineages from the lateral dermomyotome, and exhibit how factors within the network promote the smooth muscle at the expense of the striated muscle fate. This network acts as an exemplar demonstrating how lineage segregation occurs within epithelial primordia by integrating inputs from competing factors. PMID:25015411

  4. Striated muscle involvement in experimental oral infection by herpes simplex virus type 1.

    PubMed

    Gonzalez, María Inés; Sanjuan, Norberto A

    2013-07-01

    Herpes simplex virus type 1 is one of the most frequent causes of oral infection in humans, especially during early childhood. Several experimental models have been developed to study the pathogenesis of this virus but all of them employed adult animals. In this work, we developed an experimental model that uses mice younger than 4 days old, to more closely resemble human infection. Mice were infected subcutaneously with the prototype strain McIntyre of Herpes simplex-1, and the progression of infection was studied by immunoperoxidase. All animals died within 24-72 h post-infection, while viral antigens were found in the oral epithelium, nerves and brain. The most striking result was the finding of viral antigens in the nucleus and cytoplasm of cells belonging to striated muscles. Organotypic cultures of striated muscles were performed, and viral replication was observed in them by immunocytochemistry, electron microscopy and viral isolation. We conclude that the infection of striated muscles is present from the onset of oral infection and, eventually, could explain some clinical observations in humans. PMID:23445118

  5. DisAp-dependent striated fiber elongation is required to organize ciliary arrays

    PubMed Central

    Galati, Domenico F.; Bonney, Stephanie; Kronenberg, Zev; Clarissa, Christina; Yandell, Mark; Elde, Nels C.; Jerka-Dziadosz, Maria; Giddings, Thomas H.; Frankel, Joseph

    2014-01-01

    Cilia-organizing basal bodies (BBs) are microtubule scaffolds that are visibly asymmetrical because they have attached auxiliary structures, such as striated fibers. In multiciliated cells, BB orientation aligns to ensure coherent ciliary beating, but the mechanisms that maintain BB orientation are unclear. For the first time in Tetrahymena thermophila, we use comparative whole-genome sequencing to identify the mutation in the BB disorientation mutant disA-1. disA-1 abolishes the localization of the novel protein DisAp to T. thermophila striated fibers (kinetodesmal fibers; KFs), which is consistent with DisAp’s similarity to the striated fiber protein SF-assemblin. We demonstrate that DisAp is required for KFs to elongate and to resist BB disorientation in response to ciliary forces. Newly formed BBs move along KFs as they approach their cortical attachment sites. However, because they contain short KFs that are rotated, BBs in disA-1 cells display aberrant spacing and disorientation. Therefore, DisAp is a novel KF component that is essential for force-dependent KF elongation and BB orientation in multiciliary arrays. PMID:25533842

  6. Myocardium and striated muscle damage caused by licit or illicit drugs.

    PubMed

    Tóth, Anita Réka; Varga, Tibor

    2009-04-01

    Illicit and central nervous system active licit drug consumption related deaths are mainly the consequences of either unintentional or intentional overdose. According to the data in the relevant literature occurrences of different organ damages are also observable and this can play a role in death, as well. Organ damages may appear simultaneously with overdosing or can be extended in time, which may lead to proving the cause of death and establishing the relationships with previous medication difficult. The most frequent damage observed is rhabdomyolysis syndrome, which has been mainly described after cocaine or opium consumption. Authors present four cases from the autopsy documentation of the period between 2003 and 2008 at the Institute of Forensic Medicine, University of Szeged, Hungary in which illicit drug consumption or neuroleptic licit drug medication resulted in development of myocardium and striated muscle damage. The dominant clinical symptoms were hyperthermia, renal and circulatory failure. The laboratory tests showed renal and liver insufficiency; in addition the CK and CK-MB level increase suggested damage in striated muscles. The focal myocardium and striated muscle damage could be assessed as the cause of death in one case, but microscopic investigation proved the presence of damage in each. PMID:19342269

  7. Molecular organization in striated domains induced by transmembrane alpha-helical peptides in dipalmitoyl phosphatidylcholine bilayers.

    PubMed

    Sparr, Emma; Ganchev, Dragomir N; Snel, Margot M E; Ridder, Anja N J A; Kroon-Batenburg, Loes M J; Chupin, Vladimir; Rijkers, Dirk T S; Killian, J Antoinette; de Kruijff, Ben

    2005-01-11

    Transmembrane (TM) alpha-helical peptides with neutral flanking residues such as tryptophan form highly ordered striated domains when incorporated in gel-state 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) bilayers and inspected by atomic force microscopy (AFM) (1). In this study, we analyze the molecular organization of these striated domains using AFM, photo-cross-linking, fluorescence spectroscopy, nuclear magnetic resonance (NMR), and X-ray diffraction techniques on different functionalized TM peptides. The results demonstrate that the striated domains consist of linear arrays of single TM peptides with a dominantly antiparallel organization in which the peptides interact with each other and with lipids. The peptide arrays are regularly spaced by +/-8.5 nm and are separated by somewhat perturbed gel-state lipids with hexagonally organized acyl chains, which have lost their tilt. This system provides an example of how domains of peptides and lipids can be formed in membranes as a result of a combination of specific peptide-peptide and peptide-lipid interactions. PMID:15628840

  8. The significance of striated muscle in the mammary glands of marsupials.

    PubMed Central

    Griffiths, M; Slater, E

    1988-01-01

    The distribution and amounts of striated muscle within the mammary glands of pouched and pouchless marsupials from Australia and South America are described. Invasions into the mammary secretory parenchyma in pouchless marsupials by swathes of striated muscle from the ilio-marsupialis muscle are massive, in some instances concentrated into discrete muscles, which are inserted on to the bases of the teats; the name retractor mammae is proposed for these muscles. In pouched marsupials striated muscle penetrates the parenchyma, but the distribution is diffuse and the muscle strands are not inserted on to teats except in the instance of the glands of the honey possum Tarsipes rostratus. The young of anaesthetised pouchless marsupials hang down from the teats; as anaesthesia wears off they are hauled up tightly into the mammary area. It is concluded that this is a result of contraction of the retractor mammae muscles and that it is a means of protecting the naked young from injury by rough terrain. The mammary gland musculature in pouched marsupials is considered to be vestigial, but its contraction may have the function of initiating a 'tap-response' contraction of myoepithelium acting synergistically with the 'let-down' hormone mesotocin. Mechanisms of imbibition of milk by marsupial neonates, based on observations that they can suck fluid from non-distortable tubes, are discussed. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 PMID:3417541

  9. Form, function and intracortical projections of spiny neurones in the striate visual cortex of the cat.

    PubMed Central

    Martin, K A; Whitteridge, D

    1984-01-01

    We have studied the neuronal circuitry and structure-function relationships of single neurones in the striate visual cortex of the cat using a combination of electrophysiological and anatomical techniques. Glass micropipettes filled with horseradish peroxidase were used to record extracellularly from single neurones. After studying the receptive field properties, the afferent inputs of the neurones were studied by determining their latency of response to electrical stimulation at different positions along the optic pathway. Some cells were thus classified as receiving a mono- or polysynaptic input from afferents of the lateral geniculate nucleus (l.g.n.), via X- or Y-like retinal ganglion cells. Two striking correlations were found between dendritic morphology and receptive field type. All spiny stellate cells, and all star pyramidal cells in layer 4A, had receptive fields with spatially separate on and off subfields (S-type receptive fields). All the identified afferent input to these, the major cell types in layer 4, was monosynaptic from X- or Y-like afferents. Neurones receiving monosynaptic X- or Y-like input were not strictly segregated in layer 4 and the lower portion of layer 3. Nevertheless the X- and Y-like l.g.n. fibres did not converge on any of the single neurones so far studied. Monosynaptic input from the l.g.n. afferents was not restricted to cells lying within layers 4 and 6, the main termination zones of the l.g.n. afferents, but was also received by cells lying in layers 3 and 5. The projection pattern of cells receiving monosynaptic input differed widely, depending on the laminar location of the cell soma. This suggests the presence of a number of divergent paths within the striate cortex. Cells receiving indirect input from the l.g.n. afferents were located mainly within layers 2, 3 and 5. Most pyramidal cells in layer 3 had axons projecting out of the striate cortex, while many axons of the layer 5 pyramids did not. The layer 5 cells showed

  10. Ultrastructural studies of the mitochondriae in the striated muscles of birds with regard to experimental hypokinesis

    NASA Technical Reports Server (NTRS)

    Belak, M.; Kocisova, J.; Boda, K.

    1980-01-01

    Electron microscopic studies were carried out on the mitochrondria of the transversely striated muscles with regard to experimental hypokinesia. As compared to the central group the mitochondria of m. pectoralis thoracicus and the m. iliotibialis posterior in hypokinetic birds reveal marked changes. In filamentous and ovoid mitochondria, vacuoles can be observed which in some cases produced larger light formations with following disappearance of the cristae and destruction of mitochondria. Fat particles located at the poles of the altered mitochondria, sporadically occurring also laterally, presented another finding. The Z-lines of the sarcomere did not form a continuous line, but were somewhat shifted.

  11. The Popeye Domain Containing Genes and their Function in Striated Muscle

    PubMed Central

    Schindler, Roland FR; Scotton, Chiara; French, Vanessa; Ferlini, Alessandra; Brand, Thomas

    2016-01-01

    The Popeye domain containing (POPDC) genes encode a novel class of cAMP effector proteins, which are abundantly expressed in heart and skeletal muscle. Here we will review their role in striated muscle as deduced from work in cell and animal models and the recent analysis of patients carrying a missense mutation in POPDC1. Evidence suggests that POPDC proteins control membrane trafficking of interacting proteins. Furthermore, we will discuss the current catalogue of established protein-protein interactions. In recent years, the number of POPDC-interacting proteins is rising and currently includes ion channels (TREK-1), sarcolemma-associated proteins serving functions in mechanical stability (Dystrophin), compartmentalization (Caveolin 3), scaffolding (ZO-1), trafficking (NDRG4, VAMP2/3) and repair (Dysferlin), or acting as a guanine nucleotide exchange factor for Rho-family GTPases (GEFT). Recent evidence suggests that POPDC proteins might also control the cellular level of the nuclear proto-oncoprotein c-Myc. These data suggests that this family of cAMP-binding proteins probably serves multiple roles in striated muscle. PMID:27347491

  12. Single-unit and 2-deoxyglucose studies of side inhibition in macaque striate cortex.

    PubMed Central

    Born, R T; Tootell, R B

    1991-01-01

    In the course of studies to map spatial frequency tuning of neurons in layers 2 and 3 of macaque striate cortex, we found that a high proportion (70%) of cells in the interblob regions responded poorly to full-field gratings, compared with responses to single bars, edges, or delimited gratings. This was most often due to side inhibition, in which increasing the number of cycles of a grating placed within the cell's receptive field causes progressive inhibition of response. Quantitative receptive-field mappings showed, however, that the inhibition can occur within the region activated by a bar, as well as beyond it. The inhibition appears to be orientation-selective, in that a surround grating was more effective at inhibiting the response to a center grating patch if it was of similar orientation. 2-Deoxyglucose experiments confirmed that side inhibition is very widespread in the interblobs of layers 2 and 3 and suggested that it is reduced or lacking in layers 4A through 6. Since layers 2 and 3 of striate cortex are the major source of cortical projections to area V2 and beyond, the prevalence of side stopping in these laminae has implications for theories of cortical visual function. Side-stopped interblob cells may be acting as "contour-pass filters" that filter out redundant information in textured or noisy surfaces, focusing subsequent form processing on contrasts corresponding to object boundaries. Images PMID:1871122

  13. Systemic delivery of genes to striated muscles using adeno-associated viral vectors.

    PubMed

    Gregorevic, Paul; Blankinship, Michael J; Allen, James M; Crawford, Robert W; Meuse, Leonard; Miller, Daniel G; Russell, David W; Chamberlain, Jeffrey S

    2004-08-01

    A major obstacle limiting gene therapy for diseases of the heart and skeletal muscles is an inability to deliver genes systemically to muscles of an adult organism. Systemic gene transfer to striated muscles is hampered by the vascular endothelium, which represents a barrier to distribution of vectors via the circulation. Here we show the first evidence of widespread transduction of both cardiac and skeletal muscles in an adult mammal, after a single intravenous administration of recombinant adeno-associated virus pseudotype 6 vectors. The inclusion of vascular endothelium growth factor/vascular permeability factor, to achieve acute permeabilization of the peripheral microvasculature, enhanced tissue transduction at lower vector doses. This technique enabled widespread muscle-specific expression of a functional micro-dystrophin in the skeletal muscles of dystrophin-deficient mdx mice, which model Duchenne muscular dystrophy. We propose that these methods may be applicable for systemic delivery of a wide variety of genes to the striated muscles of adult mammals. PMID:15273747

  14. Perineal striated muscles: Anatomy, spinal motoneurons, and participation on copulatory behavior in male rabbits (Oryctolagus cuniculus).

    PubMed

    Zempoalteca, R; Lucio, R A; Eguibar, J R

    2008-09-01

    Despite the importance of rabbits in reproductive studies, little information is available on the anatomy and participation of the striated-perineal muscles in male copulatory behavior. In our study, we describe the gross anatomy of two striated-perineal muscles: the ischiocavernosus (ICm) and the bulbospongiosus (BSm). Both muscles have their origin at the ischiadic arc, but the ICm is inserted into the penile crura and the BSm onto the ligamentum suspensorium of the penis. The motoneurons of both muscles were identified using retrograde labeling with horseradish peroxidase coupled to wheat-germ agglutinin. Motoneurons were dispersed in the lower-lumbar and upper-sacral spinal-cord segments, instead of being aggregated in the neuronal nucleus as in other species: the rat, mouse, gerbil, cat, and man. Bilateral dennervation of the ICm or BSm or both in sexually experienced male rabbits did not affect copulatory variables measured at 10, 20, and 30 days after surgery. However, muscular dennervation produced extravaginal ejaculations in 42% of copulatory tests and no ejaculation in 7% of tests, although male pelvic thrusting occurred. These results suggest the participation of the ICm and BSm perineal muscles in penile orientation during copulation but not in seminal emission as described in other mammalian species. PMID:18563835

  15. 'Striated Delta' Clouds As Tracers Of Inertia-Gravity Wave Emission From Upper Jets And Extratropical Cyclones

    NASA Astrophysics Data System (ADS)

    Morgan, A. L.; Reeder, M. J.

    2012-12-01

    'Striated Delta' cloud formations are frequently tracers of upper-tropospheric inertia-gravity wave disturbances near the jet stream, coincident with rapid extratropical cyclogenesis (Feren, 1995). The investigation of source mechanisms in this context is important for better understanding of how and where large-amplitude inertia-gravity waves are generated, which propagate energy throughout the atmosphere and transfer it to the mean flow through breaking or attenuation processes. A seasonal study of twenty-eight Striated Delta events in the Australia/New Zealand region during May to September 2009 is analysed in the high-resolution ECMWF YOTC dataset. Mean composite analyses show that Striated Deltas occur in an upper-tropospheric environment of strong horizontal divergence, strong parcel accelerations, strong vertical motion and geostrophic imbalance. Synoptically, the Striated Delta cases occur in the poleward jet exit region near the axis of inflexion between an upstream upper trough and a downstream upper ridge. This is consistent with findings of previous studies regarding the synoptic environment characteristic of gravity wave generation. A Q-vector partitioning analysis suggests that flow curvature and advection of shear are the two greatest components to synoptic scale vertical motion forcing. The Q-Vector analysis also explains the characteristic triangular shape of the Striated Delta cloud formation. It is hypothesised that strong parcel accelerations due to curvature of the flow, as well as air parcel deceleration in the jet streak exit region, are responsible for the generation of inertia-gravity waves evident in the banding of Striated Delta clouds. Furthermore, deep convection is favoured in the poleward jet exit region by the ageostrophic circulation and is also thought to play a role in the generation of waves and the modulation of wavelengths. A distinct and interesting Striated Delta and extratropical cyclogenesis event from September 2009 is

  16. Reappraisal of intergender differences in the urethral striated sphincter explains why a completely circular arrangement is difficult in females: a histological study using human fetuses

    PubMed Central

    Takenaka, Atsushi; Rodríguez-Vázquez, Jose Francisco; Murakami, Gen; Matsubara, Akio

    2012-01-01

    To investigate why the development of a completely circular striated sphincter is so rare, we examined histological sections of 11 female and 11 male mid-term human fetuses. In male fetuses, the striated muscle initially extended in the frontal, rather than in the horizontal plane. However, a knee-like portion was absent in the female fetal urethra because, on the inferior side of the vaginal end, a wide groove for the future vestibule opened inferiorly. Accordingly, it was difficult for the developing striated muscle to surround the groove, even though there was not a great difference in width or thickness between the female vestibule and the male urethra. The development of a completely circular striated sphincter seems to be impossible in females because of interruption of the frontal plane by the groove-like vestibule. However, we cannot rule out the possibility that before descent of the vagina, the urethral striated muscle extends posteriorly. PMID:22822461

  17. Analytical study of striated nozzle flow with small radius of curvature ratio throats

    NASA Technical Reports Server (NTRS)

    Norton, D. J.; White, R. E.

    1972-01-01

    An analytical method was developed which is capable of estimating the chamber and throat conditions in a nozzle with a low radius of curvature throat. The method was programmed using standard FORTRAN 4 language and includes chemical equilibrium calculation subprograms (modified NASA Lewis program CEC71) as an integral part. The method determines detailed and gross rocket characteristics in the presence of striated flows and gives detailed results for the motor chamber and throat plane with as many as 20 discrete zones. The method employs a simultaneous solution of the mass, momentum, and energy equations and allows propellant types, 0/F ratios, propellant distribution, nozzle geometry, and injection schemes to be varied so to predict spatial velocity, density, pressure, and other thermodynamic variable distributions in the chamber as well as the throat. Results for small radius of curvature have shown good comparison to experimental results. Both gaseous and liquid injection may be considered with frozen or equilibrium flow calculations.

  18. Modulation of the cytosolic androgen receptor in striated muscle by sex steroids

    NASA Technical Reports Server (NTRS)

    Rance, N. E.; Max, S. E.

    1982-01-01

    The influence of orchiectomy (GDX) and steroid administration on the level of the cytosolic androgen receptor in the rat levator ani muscle and in rat skeletal muscles (tibialis anterior and extensor digitorum longus) was studied. Androgen receptor binding to muscle cytosol was measured using H-3 methyltrienolone (R1881) as ligand, 100 fold molar excess unlabeled R1881 to assess nonspecific binding, and 500 fold molar excess of triamcinolone acetonide to prevent binding to glucocorticoid and progestin receptors. Results demonstrate that modification of the levels of sex steroids can alter the content of androgen receptors of rat striated muscle. Data suggest that: (1) cytosolic androgen receptor levels increase after orchiectomy in both levator ani muscle and skeletal muscle; (2) the acute increase in receptor levels is blocked by an inhibitor of protein synthesis; and (3) administration of estradiol-17 beta to castrated animals increases receptor binding in levator ani muscle but not in skeletal muscle.

  19. Local and global principles of striate cortical organization: an advanced model.

    PubMed

    Bauer, R; Dow, B M

    1991-01-01

    A model of the functional architecture in monkey striate cortex is proposed, based on recent data, in which the global structure is a result of the local structure. The local structure itself is organized around the cytochrome oxidase blobs. It is characterized by different anisotropic distributions of preferred orientations in upper and lower layers. In particular, the upper layers show a bias for "radial" orientations and the lower layers show a bias for "concentric" orientations (Bauer and Dow 1989). This organization may derive from the symmetry of the visual field and visual system which tends to be radial or concentric rather than cartesian. Functionally, the increased sensitivities of the different radial and concentric maps of orientation and movement detectors seem to be an adaptive fit to optic flow fields on the retina during complex movements of the subject in its environment. PMID:1650592

  20. The regulation and function of the striated muscle activator of rho signaling (STARS) protein

    PubMed Central

    Wallace, Marita A.; Lamon, Séverine; Russell, Aaron P.

    2012-01-01

    Healthy living throughout the lifespan requires continual growth and repair of cardiac, smooth, and skeletal muscle. To effectively maintain these processes muscle cells detect extracellular stress signals and efficiently transmit them to activate appropriate intracellular transcriptional programs. The striated muscle activator of Rho signaling (STARS) protein, also known as Myocyte Stress-1 (MS1) protein and Actin-binding Rho-activating protein (ABRA) is highly enriched in cardiac, skeletal, and smooth muscle. STARS binds actin, co-localizes to the sarcomere and is able to stabilize the actin cytoskeleton. By regulating actin polymerization, STARS also controls an intracellular signaling cascade that stimulates the serum response factor (SRF) transcriptional pathway; a pathway controlling genes involved in muscle cell proliferation, differentiation, and growth. Understanding the activation, transcriptional control and biological roles of STARS in cardiac, smooth, and skeletal muscle, will improve our understanding of physiological and pathophysiological muscle development and function. PMID:23248604

  1. Neurons in Striate Cortex Signal Disparity in Half-Matched Random-Dot Stereograms

    PubMed Central

    Read, Jenny C. A.; Cumming, Bruce G.

    2016-01-01

    Human stereopsis can operate in dense “cyclopean” images containing no monocular objects. This is believed to depend on the computation of binocular correlation by neurons in primary visual cortex (V1). The observation that humans perceive depth in half-matched random-dot stereograms, although these stimuli have no net correlation, has led to the proposition that human depth perception in these stimuli depends on a distinct “matching” computation possibly performed in extrastriate cortex. However, recording from disparity-selective neurons in V1 of fixating monkeys, we found that they are in fact able to signal disparity in half-matched stimuli. We present a simple model that explains these results. This reinstates the view that disparity-selective neurons in V1 provide the initial substrate for perception in dense cyclopean stimuli, and strongly suggests that separate correlation and matching computations are not necessary to explain existing data on mixed correlation stereograms. SIGNIFICANCE STATEMENT The initial step in stereoscopic 3D vision is generally thought to be a correlation-based computation that takes place in striate cortex. Recent research has argued that there must be an additional matching computation involved in extracting stereoscopic depth in random-dot stereograms. This is based on the observation that humans can perceive depth in stimuli with a mean binocular correlation of zero (where a correlation-based mechanism should not signal depth). We show that correlation-based cells in striate cortex do in fact signal depth here because they convert fluctuations in the correlation level into a mean change in the firing rate. Our results reinstate the view that these cells provide a sufficient substrate for the perception of stereoscopic depth. PMID:27559177

  2. Mechanical Stretch-Induced Activation of ROS/RNS Signaling in Striated Muscle

    PubMed Central

    Ward, Christopher W.; Prosser, Benjamin L.

    2014-01-01

    Significance: Mechanical activation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) occurs in striated muscle and affects Ca2+ signaling and contractile function. ROS/RNS signaling is tightly controlled, spatially compartmentalized, and source specific. Recent Advances: Here, we review the evidence that within the contracting myocyte, the trans-membrane protein NADPH oxidase 2 (Nox2) is the primary source of ROS generated during contraction. We also review a newly characterized signaling cascade in cardiac and skeletal muscle in which the microtubule network acts as a mechanotransduction element that activates Nox2-dependent ROS generation during mechanical stretch, a pathway termed X-ROS signaling. Critical Issues: In the heart, X-ROS acts locally and affects the sarcoplasmic reticulum (SR) Ca2+ release channels (ryanodine receptors) and tunes Ca2+ signaling during physiological behavior, but excessive X-ROS can promote Ca2+-dependent arrhythmias in pathology. In skeletal muscle, X-ROS sensitizes Ca2+-permeable sarcolemmal “transient receptor potential” channels, a pathway that is critical for sustaining SR load during repetitive contractions, but when in excess, it is maladaptive in diseases such as Duchenne Musclar dystrophy. Future Directions: New advances in ROS/RNS detection as well as molecular manipulation of signaling pathways will provide critical new mechanistic insights into the details of X-ROS signaling. These efforts will undoubtedly reveal new avenues for therapeutic intervention in the numerous diseases of striated muscle in which altered mechanoactivation of ROS/RNS production has been identified. Antioxid. Redox Signal. 20, 929–936. PMID:23971496

  3. Isoform composition, gene expression and sarcomeric protein phosphorylation in striated muscle of mice after space flight

    NASA Astrophysics Data System (ADS)

    Vikhlyantsev, Ivan; Ulanova, Anna; Salmov, Nikolay; Gritsyna, Yulia; Bobylev, Alexandr; Rogachevsky, Vadim; Shenkman, Boris; Podlubnaya, Zoya

    Using RT-PCR and SDS-PAGE, changes in isoform composition, gene expression, titin and nebulin phosphorylation, as well as changes in isoform composition of myosin heavy chains in striated muscles of mice were studied after 30-day-long space flight onboard the Russian spacecraft “BION-M” No. 1. The muscle fibre-type shift from slow-to-fast was observed in m. gastrocnemius and m. tibialis anterior of animals from “Flight” group. A decrease in the content of the NT and N2A titin isoforms and nebulin in the skeletal muscles of animals from “Flight” group was found. Meanwhile, significant differences in gene expression of these proteins in skeletal muscles of mice from “Flight” and “Control” groups were not observed. Using Pro-Q Diamond stain, an increase in titin phosphorylation in m. gastrocnemius of mice from “Flight” group was detected. The content of the NT, N2BA and N2B titin isoforms in cardiac muscle of mice from “Flight” and “Control” groups did not differ, nevertheless an increase in titin gene expression in the myocardium of the “Flight” group animals was found. The observed changes will be discussed in the context of theirs role in contractile activity of striated muscles of mice in conditions of weightlessness. This work was supported by the Russian Foundation for Basic Research (grants No. 14-04-32240, 14-04-00112). Acknowledgement. We express our gratitude to the teams of Institute of Biomedical Problems RAS and “PROGRESS” Corporation involved in the preparation of the “BION-M” mission.

  4. Involvement of catecholaminergic neurons in motor innervation of striated muscle in the mouse esophagus.

    PubMed

    van der Keylen, Piet; Garreis, Fabian; Steigleder, Ruth; Sommer, Daniel; Neuhuber, Winfried L; Wörl, Jürgen

    2016-05-01

    Enteric co-innervation is a peculiar innervation pattern of striated esophageal musculature. Both anatomical and functional data on enteric co-innervation related to various transmitters have been collected in different species, although its function remains enigmatic. However, it is unclear whether catecholaminergic components are involved in such a co-innervation. Thus, we examined to identify catecholaminergic neuronal elements and clarify their relationship to other innervation components in the esophagus, using immunohistochemistry with antibodies against tyrosine hydroxylase (TH), vesicular acetylcholine transporter (VAChT), choline acetyltransferase (ChAT) and protein gene product 9.5 (PGP 9.5), α-bungarotoxin (α-BT) and PCR with primers for amplification of cDNA encoding TH and dopamine-β-hydroxylase (DBH). TH-positive nerve fibers were abundant throughout the myenteric plexus and localized on about 14% of α-BT-labelled motor endplates differing from VAChT-positive vagal nerve terminals. TH-positive perikarya represented a subpopulation of only about 2.8% of all PGP 9.5-positive myenteric neurons. Analysis of mRNA showed both TH and DBH transcripts in the mouse esophagus. As ChAT-positive neurons in the compact formation of the nucleus ambiguus were negative for TH, the TH-positive nerve varicosities on motor endplates are presumably of enteric origin, although a sympathetic origin cannot be excluded. In the medulla oblongata, the cholinergic ambiguus neurons were densely supplied with TH-positive varicosities. Thus, catecholamines may modulate vagal motor innervation of esophageal-striated muscles not only at the peripheral level via enteric co-innervation but also at the central level via projections to the nucleus ambiguus. As Parkinson's disease, with a loss of central dopaminergic neurons, also affects the enteric nervous system and dysphagia is prevalent in patients with this disease, investigation of intrinsic catecholamines in the esophagus may

  5. A striated pattern of wear in ultrahigh-molecular-weight polyethylene components of Miller-Galante total knee arthroplasty.

    PubMed

    Wimmer, M A; Andriacchi, T P; Natarajan, R N; Loos, J; Karlhuber, M; Petermann, J; Schneider, E; Rosenberg, A G

    1998-01-01

    Wear of the polyethylene tibial components is a potential cause of failure in total knee arthroplasty. In addition to pitting, burnishing, and scratching, subtle striations on the bearing portion of the tibial surface have been observed in components retrieved relatively early after implantation. The striated pattern most typically occurred in areas centrally located within the articulating surface. The striations were anteroposterior directed and were identified as local cold flow at the surface. There was a strong correlation between the medial and lateral striated areas, suggesting that these patterns are related to cyclic rolling of the knee. The general characteristics and alignment of the striations could be attributed to the compressive and tractive forces occurring during femoral rollback. For the clinician, these results suggest that kinematics, as well as contact stress, should be considered when evaluating wear of polyethylene components. PMID:9493532

  6. Striated domains: self-organizing ordered assemblies of transmembrane alpha-helical peptides and lipids in bilayers.

    PubMed

    de Kruijff, Ben; Killian, J Antoinette; Ganchev, Dragomir N; Rinia, Hilde A; Sparr, Emma

    2006-03-01

    This review summarizes the knowledge on striated domains, which are ordered assemblies of transmembrane peptides and lipids under gel-state conditions. The structure, mechanism of function and utility of this system as a model for domain formation is described, resulting in a molecular description of the domains and a discussion on the relevance of these insights for the function/formation and structure of similar domains in biological membranes. PMID:16542143

  7. Evaluation of Vascular Delivery Methodologies to Enhance rAAV6-mediated Gene Transfer to Canine Striated Musculature

    PubMed Central

    Gregorevic, Paul; Schultz, Brian R; Allen, James M; Halldorson, Jeffrey B; Blankinship, Michael J; Meznarich, Norman A; Kuhr, Christian S; Doremus, Caitlin; Finn, Eric; Liggitt, Denny; Chamberlain, Jeffrey S

    2009-01-01

    A growing body of research supports the development of recombinant adeno-associated viral (rAAV) vectors for delivery of gene expression cassettes to striated musculature as a method of treating severe neuromuscular conditions. However, it is unclear whether delivery protocols that achieve extensive gene transfer in mice can be adapted to produce similarly extensive gene transfer in larger mammals and ultimately patients. Consequently, we sought to investigate methodological modifications that would facilitate rAAV-mediated gene transfer to the striated musculature of canines. A simple procedure incorporating acute (i) occlusion of limb blood flow, (ii) exsanguination via compression bandage, and (iii) vector “dwell” time of <20 minutes, markedly enhanced the transduction of limb muscles, compared with a simple bolus limb infusion of vector. A complementary method whereby vector was infused into the jugular vein led to efficient transduction of cardiomyocytes and to a lesser degree the diaphragm. Together these methods can be used to achieve transgene expression in heart, diaphragm, and limb muscles of juvenile dogs using rAAV6 vectors. These results establish that rAAV-mediated gene delivery is a viable approach to achieving systemic transduction of striated musculature in mammals approaching the dimensions of newborn humans. PMID:19471246

  8. Regulation of structure and function of sarcomeric actin filaments in striated muscle of the nematode Caenorhabditis elegans

    PubMed Central

    Ono, Shoichiro

    2014-01-01

    The nematode Caenorhabditis elegans has been used as a valuable system to study structure and function of striated muscle. The body wall muscle of C. elegans is obliquely striated muscle with highly organized sarcomeric assembly of actin, myosin, and other accessary proteins. Genetic and molecular biological studies in C. elegans have identified a number of genes encoding structural and regulatory components for the muscle contractile apparatuses, and many of them have counterparts in mammalian cardiac and skeletal muscles or striated muscles in other invertebrates. Applicability of genetics, cell biology, and biochemistry has made C. elegans an excellent system to study mechanisms of muscle contractility and assembly and maintenance of myofibrils. This review focuses on the regulatory mechanisms of structure and function of actin filaments in the C. elegans body wall muscle. Sarcomeric actin filaments in C. elegans muscle are associated with the troponin-tropomyosin system that regulates the actin-myosin interaction. Proteins that bind to the side and ends of actin filaments support ordered assembly of thin filaments. Furthermore, regulators of actin dynamics play important roles in initial assembly, growth, and maintenance of sarcomeres. The knowledge acquired in C. elegans can serve as bases to understand the basic mechanisms of muscle structure and function. PMID:25125169

  9. Increased cytosolic androgen receptor binding in rat striated muscle following denervation and disuse

    NASA Technical Reports Server (NTRS)

    Bernard, P. A.; Fishman, P. S.; Max, S. R.; Rance, N. E.

    1984-01-01

    The effects of denervation and disuse on cytosolic androgen receptor binding by rat striated muscle are investigated. Denervation of the extensor digitorum longus and tibialis anterior muscles caused by a 40-50-percent increase in cytosolic androgen receptor concentration with no change in apparent binding affinity. This effect was evident at 6 h postdenervation, maximal at 24 h, and declined to 120 percent of the control level 72 h after denervation. A 40-percent increase in cytosolic androgen receptor concentration was also noted 24 hr after denervation of the hormone-sensitive levator ani muscle. The effect of denervation on androgen receptors was blocked by in vivo injection of cycloheximide; therefore, de novo receptor synthesis probably is not involved in the observed increase. Disuse, produced by subperineurial injection of tetrodotoxin into the tibial and common peroneal branches of the sciatic nerve, mimicked the effect of denervation on androgen receptor binding, suggesting that neuromuscular activity is important in regulation of receptor concentration. Possible mechanisms subserving this effect are discussed.

  10. Revealing T-Tubules in Striated Muscle with New Optical Super-Resolution Microscopy Techniquess.

    PubMed

    Jayasinghe, Isuru D; Clowsley, Alexander H; Munro, Michelle; Hou, Yufeng; Crossman, David J; Soeller, Christian

    2015-01-01

    The t-tubular system plays a central role in the synchronisation of calcium signalling and excitation-contraction coupling in most striated muscle cells. Light microscopy has been used for imaging t-tubules for well over 100 years and together with electron microscopy (EM), has revealed the three-dimensional complexities of the t-system topology within cardiomyocytes and skeletal muscle fibres from a range of species. The emerging super-resolution single molecule localisation microscopy (SMLM) techniques are offering a near 10-fold improvement over the resolution of conventional fluorescence light microscopy methods, with the ability to spectrally resolve nanometre scale distributions of multiple molecular targets. In conjunction with the next generation of electron microscopy, SMLM has allowed the visualisation and quantification of intricate t-tubule morphologies within large areas of muscle cells at an unprecedented level of detail. In this paper, we review recent advancements in the t-tubule structural biology with the utility of various microscopy techniques. We outline the technical considerations in adapting SMLM to study t-tubules and its potential to further our understanding of the molecular processes that underlie the sub-micron scale structural alterations observed in a range of muscle pathologies. PMID:26913143

  11. Dietary Fish Oil Blocks the Microcirculatory Manifestations of Ischemia- Reperfusion Injury in Striated Muscle in Hamsters

    NASA Astrophysics Data System (ADS)

    Lehr, Hans-Anton; Hubner, Christoph; Nolte, Dirk; Kohlschutter, Alfried; Messmer, Konrad

    1991-08-01

    Epidemiologic observations and experimental studies have demonstrated a protective effect of dietary fish oil on the clinical manifestations of ischemia-reperfusion injury. To investigate the underlying mechanisms, we used the dorsal skinfold chamber model for intravital fluorescence microscopy of the microcirculation in striated muscle of awake hamsters. In control hamsters (n = 7), reperfusion after a 4-hr pressure-induced ischemia to the muscle tissue elicited the adhesion of fluorescently stained leukocytes to the endothelium of postcapillary venules, capillary obstruction, and the breakdown of endothelial integrity. These microvascular manifestations of ischemia-reperfusion injury were significantly attenuated in animals (n = 7) when fed with a fish oil-enriched diet for 4 weeks prior to the experiments. In leukocyte total lipids, the fish oil diet resulted in a substantial displacement of arachidonic acid, the precursor of the potent adhesionpromoting leukotriene (LT) B_4, by fish oil-derived eicosapentaenoic acid, the precursor of biologically less potent LTB_5, emphasizing the mediator role of LTB_4 in ischemia-reperfusion injury. These results suggest that the preservation of microvascular perfusion by dietary fish oil contributes to its protective effects on the clinical manifestations of ischemia-reperfusion injury.

  12. Pulsed nuclear magnetic resonance study of 39K in frog striated muscle.

    PubMed Central

    Civan, M M; McDonald, G G; Pring, M; Shporer, M

    1976-01-01

    Samples of 1 M KCl solution and 10 samples of intact frog striated muscle were studied at 4-7 degrees C and/or at 21-22 degrees C. Field inhomogeneity was minimized by using small sample volumes and by using a superconducting magnet designed specifically to provide highly homogeneous fields. In the present experiments, magnetic field inhomogeneity was measured to contribute less than 15% to the free induction decay observed for intracellular 39K. The signal-to-noise ratio of the measurements was enhanced by means of extensive time-averaging. The rates of nuclear relaxation for 39K in aqueous solution were 22 +/- 3 (mean +/- 95% confidence limits) s-1 at 4-7 degrees C and 15 +/- 2 s-1 at 21-22 degrees C. For intracellular 39K, (1/T2) was measured to be 327 +/- 22 s-1 and 229 +/- 10 s-1 at the lower and higher temperatures, respectively. The corresponding values for (1/T1) in the same muscle samples were 198 +/- 31 s-1 and 79 +/- 15 s-1 at 4-7 degrees C and at 21-22 degrees C, respectively. These results for 39K are similar to those previously obtained for intracellular 23Na. Since less than 1% of the intracellular 23Na has been estimated to be immobilized, fractional immobilization of intracellular 39K is also likely to be insubstantial. PMID:1086686

  13. Background luminance affects the detection of microampere currents delivered to macaque striate cortex.

    PubMed

    Tehovnik, Edward J; Slocum, Warren M

    2009-07-01

    Monkeys detect electrical microstimulation delivered to the striate cortex (area V1). We examined whether the ability of monkeys to detect such stimulation is affected by background luminance. While remaining fixated on a spot of light centered on a monitor, a monkey was required to detect a 100 ms train of electrical stimulation delivered to a site within area V1 situated from 1 to 1.5 mm below the cortical surface. A monkey signaled the delivery of stimulation by depressing a lever after which it was rewarded with a drop of apple juice. Control trials were interleaved during which time no stimulation was delivered and the monkey was rewarded for not depressing the lever. Biphasic pulses were delivered at 200 Hz and the current ranged from 2 to 30 microA using 0.2 ms anode-first biphasic pulses. The background luminance level of the monitor could be varied from 0.005 to 148 cd/m(2). It was found that, for monitor luminance levels below 10 cd/m(2), the current threshold to evoke a detection response increased. We discuss the significance of this result with regard to phosphenes elicited from human V1 and in relation to visual perception. PMID:19558620

  14. Characterization of beta-connectin (titin 2) from striated muscle by dynamic light scattering.

    PubMed Central

    Higuchi, H; Nakauchi, Y; Maruyama, K; Fujime, S

    1993-01-01

    Connectin (titin) is a large filamentous protein (single peptide) with a molecular mass of approximately 3 MDa, contour length approximately 900 nm, and diameter approximately 4 nm, and resides in striated muscle. Connectin links the thick filaments to the Z-lines in a sarcomere and produces a passive elastic force when muscle fiber is stretched. The aim of this study is to elucidate some aspects of physical properties of isolated beta-connectin (titin 2), a proteolytic fragment of connectin, by means of dynamic light-scattering (DLS) spectroscopy. The analysis of DLS spectra for beta-connectin gave the translational diffusion coefficient of 3.60 x 10(-8) cm2/s at 10 degrees C (or the hydrodynamic radius of 44.1 nm), molecular mass little smaller than 3.0 MDa (for a literature value of sedimentation coefficient), the root-mean-square end-to-end distance of 163 nm (or the radius of gyration of 66.6 nm), and the Kuhn segment number of 30 and segment length of 30 nm (or the persistence length of 15 nm). These results permitted to estimate the flexural rigidity of 6.0 x 10(-20) dyn x cm2 for filament bending, and the elastic constant of 7 dyn/cm for extension of one persistence length. Based on a simple model, implications of the present results in muscle physiology are discussed. Images FIGURE 1 PMID:8298020

  15. The Intriguing Dual Lattices of the Myosin Filaments in Vertebrate Striated Muscles: Evolution and Advantage

    PubMed Central

    Luther, Pradeep K.; Squire, John M.

    2014-01-01

    Myosin filaments in vertebrate striated muscle have a long roughly cylindrical backbone with cross-bridge projections on the surfaces of both halves except for a short central bare zone. In the middle of this central region the filaments are cross-linked by the M-band which holds them in a well-defined hexagonal lattice in the muscle A-band. During muscular contraction the M-band-defined rotation of the myosin filaments around their long axes influences the interactions that the cross-bridges can make with the neighbouring actin filaments. We can visualise this filament rotation by electron microscopy of thin cross-sections in the bare-region immediately adjacent to the M-band where the filament profiles are distinctly triangular. In the muscles of teleost fishes, the thick filament triangular profiles have a single orientation giving what we call the simple lattice. In other vertebrates, for example all the tetrapods, the thick filaments have one of two orientations where the triangles point in opposite directions (they are rotated by 60° or 180°) according to set rules. Such a distribution cannot be developed in an ordered fashion across a large 2D lattice, but there are small domains of superlattice such that the next-nearest neighbouring thick filaments often have the same orientation. We believe that this difference in the lattice forms can lead to different contractile behaviours. Here we provide a historical review, and when appropriate cite recent work related to the emergence of the simple and superlattice forms by examining the muscles of several species ranging back to primitive vertebrates and we discuss the functional differences that the two lattice forms may have. PMID:25478994

  16. Effects of 6-hydroxydopamine on visual deprivation in the kitten striate cortex.

    PubMed

    Daw, N W; Rader, R K; Robertson, T W; Ariel, M

    1983-05-01

    We tested the effects of 6-hydroxydopamine (6-OHDA) on two forms of visual deprivation--monocular and directional deprivation. In normal kittens monocular deprivation leads to a change in the ocular dominance histogram recorded from the visual cortex, and directional deprivation leads to a change in the percentage of directionally sensitive cells responding to the appropriate direction of movement. 6-OHDA was infused into the occipital cortex prior to the peak of the critical period for the effects of visual deprivation. In agreement with the results of Kasamatsu et al. (Kasamatsu, T., and J. D. Pettigrew (1979) J. Comp. Neurol. 185: 139-162; Kasamatsu, T., J. D. Pettigrew, and M. Ary (1979) J. Comp. Neurol. 185: 163-182), suture of one eye (monocular deprivation) after the 6-OHDA treatment did not lead to a shift in ocular dominance in the area of striate cortex infused. Moreover, rearing kittens in an environment continually moving past them in one direction (directional deprivation) did not lead to a change in the percentage of cells preferring movement in that direction. In both rearing procedures the 6-OHDA did not make the cells in the cortex nonspecific, compared to cells recorded from the cortex of animals reared similarly but without infusion of 6-OHDA. Monocular and directional deprivation are forms of visual deprivation with different critical periods, probably involving different synapses. Therefore, the effect of 6-OHDA on visual deprivation is a general one, involving more than one kind of visual deprivation. In both cases 6-OHDA abolishes the plasticity of the visual cortex. PMID:6405018

  17. Binocular interaction fields of single units in the cat striate cortex

    PubMed Central

    Bishop, P. O.; Henry, G. H.; Smith, C. J.

    1971-01-01

    1. Based on average response histograms to an optimal stimulus, binocular interaction field plots were obtained from twenty-five simple neurones in the striate cortex of the cat. Each binocularly activated cell has two interaction fields, one for each eye. The binocular interaction field for one eye plots the changes in the amplitude of the response from the other eye as the two receptive fields of the binocularly activated cell are moved across one another, first into and then out of alignment in the plane of the optimal stimulus (tangent screen). 2. The binocular interaction field provides an important clue to the nature of the spatial organization of the excitatory and inhibitory regions of the monocular receptive field. The commonest type of receptive field organization has regions of inhibition (inhibitory side bands) to either side of the discharge centre in the direction at right angles to the optimal stimulus orientation. As well as inhibition, there are subliminal excitatory effects. 3. Binocular interaction fields differ with the various cell types, i.e. cells that are discharged only from the one eye, cells binocularly discharged with very weak or absent monocular responses and cells showing binocularly opposite direction selectivity. 4. Marked facilitation to an optimal stimulus occurs when the two receptive fields of a binocularly activated neurone are in accurate alignment. Facilitation switches to depression for very small degrees of receptive field misalignment in a direction at right angles to the optimal stimulus orientation. These observations are of importance in relation to mechanisms for binocular single vision and depth discrimination. PMID:4934209

  18. Evidence for multiple extra-striate mechanisms behind perception of visual motion gradients.

    PubMed

    Meso, Andrew Isaac; Hess, Robert F

    2012-07-01

    Perceiving motion patterns in visual scenes in which speed or motion direction varies over space while average luminance remains constant presents a processing task that requires at least two separate stages of neural spatio-temporal filtering. We have previously probed the transfer of information between these stages of filtering identifying a largely scale invariant process in which narrowband initial motion sensitive filters are coupled with a broad range of spatial frequencies of secondary filters, with an optimal coupling - in terms of optimal observer visual sensitivity - at a frequency ratio of around twelve. In the current work, we used the same stimulus to investigate the possible presence of multiple secondary filtering mechanisms and their associated bandwidths. Using a forced choice psychophysical task with both a detection and an identification component, we presented experimental blocks containing stimuli with one of two different modulator frequencies in each trial to measure the frequency difference at which the detection performance matched the identification of the frequency. We found that at a frequency differences of about 2.2 octaves, performance of both tasks was similar, and the processing could therefore be inferred to occur in independent frequency channels. The same observation was confirmed for stimuli presented at a longer viewing distance. We conclude that for the motion gradient stimuli, there are secondary filtering mechanisms with a moderately broad bandwidth of over 2 octaves that underlie our sensitivity for detecting motion gradients of different modulation frequency. These are likely to be implemented at least in part within the dorsal stream of extra-striate cortex. PMID:22659589

  19. Lessons from mammalian hibernators: molecular insights into striated muscle plasticity and remodeling.

    PubMed

    Tessier, Shannon N; Storey, Kenneth B

    2016-05-01

    Striated muscle shows an amazing ability to adapt its structural apparatus based on contractile activity, loading conditions, fuel supply, or environmental factors. Studies with mammalian hibernators have identified a variety of molecular pathways which are strategically regulated and allow animals to endure multiple stresses associated with the hibernating season. Of particular interest is the observation that hibernators show little skeletal muscle atrophy despite the profound metabolic rate depression and mechanical unloading that they experience during long weeks of torpor. Additionally, the cardiac muscle of hibernators must adjust to low temperature and reduced perfusion, while the strength of contraction increases in order to pump cold, viscous blood. Consequently, hibernators hold a wealth of knowledge as it pertains to understanding the natural capacity of myocytes to alter structural, contractile and metabolic properties in response to environmental stimuli. The present review outlines the molecular and biochemical mechanisms which play a role in muscular atrophy, hypertrophy, and remodeling. In this capacity, four main networks are highlighted: (1) antioxidant defenses, (2) the regulation of structural, contractile and metabolic proteins, (3) ubiquitin proteosomal machinery, and (4) macroautophagy pathways. Subsequently, we discuss the role of transcription factors nuclear factor (erythroid-derived 2)-like 2 (Nrf2), Myocyte enhancer factor 2 (MEF2), and Forkhead box (FOXO) and their associated posttranslational modifications as it pertains to regulating each of these networks. Finally, we propose that comparing and contrasting these concepts to data collected from model organisms able to withstand dramatic changes in muscular function without injury will allow researchers to delineate physiological versus pathological responses. PMID:26982616

  20. Effect of temporal predictability on exogenous attentional modulation of feedforward processing in the striate cortex.

    PubMed

    Dassanayake, Tharaka L; Michie, Patricia T; Fulham, Ross

    2016-07-01

    Non-informative peripheral visual cues facilitate extrastriate processing of targets [as indexed by enhanced amplitude of contralateral P1 event-related potential (ERP) component] presented at the cued location as opposed to those presented at uncued locations, at short cue-target stimulus onset asynchrony (SOA). Recently, two lines of research are emerging to suggest that the locus of attentional modulation is flexible and depends on 1) perceptual load and 2) temporal predictability of visual stimuli. We aimed to examine the effect of temporal predictability on attentional modulation of feed-forward activation of the striate cortex (as indexed by the C1 ERP component) by high-perceptual-load (HPL) stimuli. We conducted two ERP experiments where exogenously-cued HPL targets were presented under two temporal predictability conditions. In Experiment 1 [high-temporal-predictability (HTP) condition], 17 healthy subjects (age 18-26years) performed a line-orientation discrimination task on HPL targets presented in the periphery of the left upper or diagonally opposite right lower visual field, validly or invalidly cued by peripheral cues. SOA was fixed at 160ms. In Experiment 2 [low-temporal-predictability (LTP) condition], (n=10, age 19-36years) we retained HPL stimuli but randomly intermixed short-SOA trials with long-SOA (1000ms) trials in the task-blocks. In Experiment 1 and the short-SOA condition of the Experiment 2, validly-cued targets elicited significantly faster reaction times and larger contralateral P1, consistent with previous literature. A significant attentional enhancement of C1 amplitude was also observed in the HTP, but not LTP condition. The findings suggest that exogenous visual attention can facilitate the earliest stage of cortical processing under HTP conditions. PMID:27114044

  1. Contrasting effects of strabismic amblyopia on metabolic activity in superficial and deep layers of striate cortex.

    PubMed

    Adams, Daniel L; Economides, John R; Horton, Jonathan C

    2015-05-01

    To probe the mechanism of visual suppression, we have raised macaques with strabismus by disinserting the medial rectus muscle in each eye at 1 mo of age. Typically, this operation produces a comitant, alternating exotropia with normal acuity in each eye. Here we describe an unusual occurrence: the development of severe amblyopia in one eye of a monkey after induction of exotropia. Shortly after surgery, the animal demonstrated a strong fixation preference for the left eye, with apparent suppression of the right eye. Later, behavioral testing showed inability to track or to saccade to targets with the right eye. With the left eye occluded, the animal demonstrated no visually guided behavior. Optokinetic nystagmus was absent in the right eye. Metabolic activity in striate cortex was assessed by processing the tissue for cytochrome oxidase (CO). Amblyopia caused loss of CO in one eye's rows of patches, presumably those serving the blind eye. Layers 4A and 4B showed columns of reduced CO, in register with pale rows of patches in layer 2/3. Layers 4C, 5, and 6 also showed columns of CO activity, but remarkably, comparison with more superficial layers showed a reversal in contrast. In other words, pale CO staining in layers 2/3, 4A, and 4B was aligned with dark CO staining in layers 4C, 5, and 6. No experimental intervention or deprivation paradigm has been reported previously to produce opposite effects on metabolic activity in layers 2/3, 4A, and 4B vs. layers 4C, 5, and 6 within a given eye's columns. PMID:25810480

  2. Large-scale Models Reveal the Two-component Mechanics of Striated Muscle

    PubMed Central

    Jarosch, Robert

    2008-01-01

    This paper provides a comprehensive explanation of striated muscle mechanics and contraction on the basis of filament rotations. Helical proteins, particularly the coiled-coils of tropomyosin, myosin and α-actinin, shorten their H-bonds cooperatively and produce torque and filament rotations when the Coulombic net-charge repulsion of their highly charged side-chains is diminished by interaction with ions. The classical “two-component model” of active muscle differentiated a “contractile component” which stretches the “series elastic component” during force production. The contractile components are the helically shaped thin filaments of muscle that shorten the sarcomeres by clockwise drilling into the myosin cross-bridges with torque decrease (= force-deficit). Muscle stretch means drawing out the thin filament helices off the cross-bridges under passive counterclockwise rotation with torque increase (= stretch activation). Since each thin filament is anchored by four elastic α-actinin Z-filaments (provided with force-regulating sites for Ca2+ binding), the thin filament rotations change the torsional twist of the four Z-filaments as the “series elastic components”. Large scale models simulate the changes of structure and force in the Z-band by the different Z-filament twisting stages A, B, C, D, E, F and G. Stage D corresponds to the isometric state. The basic phenomena of muscle physiology, i. e. latency relaxation, Fenn-effect, the force-velocity relation, the length-tension relation, unexplained energy, shortening heat, the Huxley-Simmons phases, etc. are explained and interpreted with the help of the model experiments. PMID:19330099

  3. Digital image analysis of striated skeletal muscle tissue injury during reperfusion after induced ischemia

    NASA Astrophysics Data System (ADS)

    Rosero Salazar, Doris Haydee; Salazar Monsalve, Liliana

    2015-01-01

    Conditions such as surgical procedures or vascular diseases produce arterial ischemia and reperfusion injuries, which generate changes in peripheral tissues and organs, for instance, in striated skeletal muscle. To determine such changes, we conducted an experimental method in which 42 male Wistar rat were selected, to be undergone to tourniquet application on the right forelimb and left hind limb, to induce ischemia during one and three hours, followed by reperfusion periods starting at one hour and it was prolonged up to 32 days. Extensor carpi radialis longus and soleus respectively, were obtained to be processed for histochemical and morphometric analysis. By means of image processing and detection of regions of interest, variations of areas occupied by muscle fibers and intramuscular extracellular matrix (IM-ECM) throughout reperfusion were observed. In extensor carpi radialis longus, results shown reduction in the area occupied by muscle fibers; this change is significant between one hour and three hours ischemia followed by 16 hours, 48 hours and 32 days reperfusión (p˂0.005). To compare only periods of reperfusión that continued to three hours ischemia, were found significant differences, as well. For area occupied by IM-ECM, were identified increments in extensor carpi radialis longus by three hours ischemia and eight to 16 days reperfusion; in soleus, was observed difference by one hour ischemia with 42 hours reperfusion, and three hours ischemia followed by four days reperfusion (p˂0.005). Skeletal muscle develops adaptive changes in longer reperfusion, to deal with induced injury. Descriptions beyond 32 days reperfusion, can determine recovering normal pattern.

  4. Contrasting effects of strabismic amblyopia on metabolic activity in superficial and deep layers of striate cortex

    PubMed Central

    Adams, Daniel L.; Economides, John R.

    2015-01-01

    To probe the mechanism of visual suppression, we have raised macaques with strabismus by disinserting the medial rectus muscle in each eye at 1 mo of age. Typically, this operation produces a comitant, alternating exotropia with normal acuity in each eye. Here we describe an unusual occurrence: the development of severe amblyopia in one eye of a monkey after induction of exotropia. Shortly after surgery, the animal demonstrated a strong fixation preference for the left eye, with apparent suppression of the right eye. Later, behavioral testing showed inability to track or to saccade to targets with the right eye. With the left eye occluded, the animal demonstrated no visually guided behavior. Optokinetic nystagmus was absent in the right eye. Metabolic activity in striate cortex was assessed by processing the tissue for cytochrome oxidase (CO). Amblyopia caused loss of CO in one eye's rows of patches, presumably those serving the blind eye. Layers 4A and 4B showed columns of reduced CO, in register with pale rows of patches in layer 2/3. Layers 4C, 5, and 6 also showed columns of CO activity, but remarkably, comparison with more superficial layers showed a reversal in contrast. In other words, pale CO staining in layers 2/3, 4A, and 4B was aligned with dark CO staining in layers 4C, 5, and 6. No experimental intervention or deprivation paradigm has been reported previously to produce opposite effects on metabolic activity in layers 2/3, 4A, and 4B vs. layers 4C, 5, and 6 within a given eye's columns. PMID:25810480

  5. Mitochondrial DNA structure and expression in specialized subtypes of mammalian striated muscle.

    PubMed Central

    Annex, B H; Williams, R S

    1990-01-01

    Mitochondrial DNA (mt DNA) in cells of vertebrate organisms can assume an unusual triplex DNA structure known as the displacement loop (D loop). This triplex DNA structure forms when a partially replicated heavy strand of mtDNA (7S mtDNA) remains annealed to the light strand, displacing the native heavy strand in this region. The D-loop region contains the promoters for both heavy- and light-strand transcription as well as the origin of heavy-strand replication. However, the distribution of triplex and duplex forms of mtDNA in relation to respiratory activity of mammalian tissues has not been systematically characterized, and the functional significance of the D-loop structure is unknown. In comparisons of specialized muscle subtypes within the same species and of the same muscle subtype in different species, the relative proportion of D-loop versus duplex forms of mtDNA in striated muscle tissues of several mammalian species demonstrated marked variation, ranging from 1% in glycolytic fast skeletal fibers of the rabbit to 65% in the mouse heart. There was a consistent and direct correlation between the ratio of triplex to duplex forms of mtDNA and the capacity of these tissues for oxidative metabolism. The proportion of D-loop forms likewise correlated directly with mtDNA copy number, mtRNA abundance, and the specific activity of the mtDNA (gamma) polymerase. The D-loop form of mtDNA does not appear to be transcribed at greater efficiency than the duplex form, since the ratio of mtDNA copy number to mtRNA was unrelated to the proportion of triplex mtDNA genomes. However, tissues with a preponderance of D-loop forms tended to express greater levels of cytochrome b mRNA relative to mitochondrial rRNA transcripts, suggesting that the triplex structure may be associated with variations in partial versus full-length transcription of the heavy strand. Images PMID:1700273

  6. Position-specific adaptation in complex cell receptive fields of the cat striate cortex.

    PubMed

    Marlin, S; Douglas, R; Cynader, M

    1993-06-01

    1. Responses of complex cells in cat striate cortex were studied with flashed light slit stimuli. The responses to slits flashed in different positions in the receptive field were assessed quantitatively before and after periods of prolonged stimulation of one small region of the receptive field. This type of prolonged stimulation resulted in reduced responsivity over a limited zone within the complex cell receptive field. 2. The adaptation-induced responsivity decrement was generally observed in both the ON and OFF response profiles but could also be restricted to one or the other. In general, the magnitude of the response decrements was greatest in the ON response profiles. The adaptation-induced response decrement did not necessarily spread throughout the receptive field but was restricted to a small region surrounding the adapted receptive field position (RFP). Adaptation spread equally widely across the ON and OFF response profiles despite the smaller adaptation effects in the OFF profile. 3. The adaptation effects from repeated stimulation at a single RFP did not spread symmetrically across the receptive field, and a given cell's preferred direction of motion indicated the direction of the asymmetric spread of the adaptation. RFPs that would be stimulated by a light slit originating at the point of adaptation and moving in the preferred direction (preferred side) showed greater adaptation-induced response decrements than did RFPs that would be stimulated by a light slit moving in the opposite direction from the point of adaptation (nonpreferred side). There was significant enhancement of responses at some RFPs on the non-preferred side of the point of adaptation. This asymmetric spread of adaptation could be caused by adaptation of inhibitory connections that contribute to complex cell direction selectivity. 4. The asymmetry of adaptation was significantly different for the ON and OFF response profiles. The asymmetric spread of adaptation for the ON response

  7. Receptive field organization of complex cells in the cat's striate cortex.

    PubMed Central

    Movshon, J A; Thompson, I D; Tolhurst, D J

    1978-01-01

    1. All complex cells in the cat's striate cortex exhibit gross non-linearities of spatial summation when tested with sinusoidal grating stimuli. Their responses to moving gratings of all but the lowest spatial frequencies are usually dominated by a component that is not modulated by the passage of the bars of the grating across the receptive field. They give responses to temporally modulated stationary gratings that consist mostly of even harmonics of the stimulus frequency and that vary little in amplitude or wave form as the spatial phase of the grating is varied. 2. We compared complex cells' receptive fields with their sensitivity to sinusoidal gratings of different spatial frequencies. Qualitatively, the receptive fields are usually two to five times wider than the bars of the gratings that stimulate them most effectively. Quantitatively, the receptive field profiles of complex cells are invariably broader than those predicted by Fourier synthesis of their spatial frequency tuning curves, and in particular lack predicted spatially antagonistic regions. 3. We further examined the receptive field organization of these cells, using pairs of stationary lines flashed synchronously on their receptive fields. If both lines are of the same polarity (bright or dark), complex cells respond to the paired stimulus much less well than they do to either of its component bars, unless the bars are separated by less than about one quarter of the width of the receptive field. If the lines are of opposite polarity, one bright and one dark, the opposite situation obtains: closely spaced bars elicit small responses, while paired bars of larger separation are much more effective. In either case, the results are independent in general character of the absolute positions of the stimuli within the receptive field; rather, they depend in a manner characteristic of each cell on the relative positions of the two bars. 4. The two-line interaction profile that plots the change in a complex

  8. Effect of halothane on isometric twitch and tetanus response and the associated heat production in striated muscle of frogs.

    PubMed

    Price, K A; Matsumoto, Y; Frederickson, E L

    1975-01-01

    The purpose of these investigations was to determine the effect of halothane on isometric contraction of striated muscle and to measure the associated heat production. This basic information is necessary before studies more directly relating to malignant hyperthermia are undertaken. Sartorius muscles were isolate from Rana pipiens during winter and summer months. It appears from these experiments that there is a prolongation of the relaxation phase of the twitch and tetanus responses with low concentrations of halothane, with a more diffuse effect on the contractile process evident at higher administered concentrations. The results of heat measurements, using a sensitive thermopile-galvanometer system, are compatible with the hypotheses that this effect on relaxation could result from either an interference with calcium reuptake by the sarcoplasmic reticulum or an increased affinity of the troponintropomyosin complex for available calcium. PMID:1080024

  9. Potential dynamics of the human striate cortex cerebrum realistic neural network under the influence of an external signal

    NASA Astrophysics Data System (ADS)

    Melnikov, Leonid A.; Novosselova, Anna V.; Blinova, Nadejda V.; Vinitsky, Sergey I.; Serov, Vladislav V.; Bakutkin, Valery V.; Camenskich, T. G.; Guileva, E. V.

    2000-03-01

    In this work the numerical investigations of a potential dynamics of a neural network as the non-linear system and dynamics of the visual nerve which connect the eye retina receptors with the striate cortex cerebrum as the answer to the through-skin excitement of the eye retina by the electrical signal were realized. The visual evoked potential is the answer and characterizes the human brain state over the structures retina state and the conduction of the visual nerve fibers. The results of these investigations were presented. Specific features of the neural network, such as the excitation and depression, we took into account too. The discussion about the model parameters, used at the time of the numerical investigation, was made. The comparative analysis of the retina potential data and the data of the external signal filing by the brain hemicerebrum visual centers was made too.

  10. Decelerating burst and complex repetitive discharges in the striated muscle of the urethral sphincter, associated with urinary retention in women.

    PubMed Central

    Fowler, C J; Kirby, R S; Harrison, M J

    1985-01-01

    A type of electromyographic activity, formerly referred to as "pseudomyotonia", can be recorded from the striated muscle of the urethral sphincter using a concentric needle electrode. There are two components to this activity, complex repetitive discharges and decelerating bursts. The latter usually dominate recordings and sound very like myotonic discharges. Analysis of these discharges indicates that they are a form of "bizarre repetitive discharge", and as such, result from ephaptic spread of excitation between muscle fibres rather than from excitation arising in the terminal branches of the motor axon. Profuse activity of this type has been found in 15 women with symptoms of urethral dysfunction, including 11 with urinary retention. It is suggested that this activity is associated with a failure of urethral sphincter relaxation. Images PMID:4056803

  11. The myosin interacting-heads motif is present in the relaxed thick filament of the striated muscle of scorpion.

    PubMed

    Pinto, Antonio; Sánchez, Fredi; Alamo, Lorenzo; Padrón, Raúl

    2012-12-01

    Electron microscopy (EM) studies of 2D crystals of smooth muscle myosin molecules have shown that in the inactive state the two heads of a myosin molecule interact asymmetrically forming a myosin interacting-heads motif. This suggested that inactivation of the two heads occurs by blocking of the actin-binding site of one (free head) and the ATP hydrolysis site of the other (blocked head). This motif has been found by EM of isolated negatively stained myosin molecules of unregulated (vertebrate skeletal and cardiac muscle) and regulated (invertebrate striated and vertebrate smooth muscle) myosins, and nonmuscle myosin. The same motif has also been found in 3D-reconstructions of frozen-hydrated (tarantula, Limulus, scallop) and negatively stained (scallop, vertebrate cardiac) isolated thick filaments. We are carrying out studies of isolated thick filaments from other species to assess how general this myosin interacting-heads motif is. Here, using EM, we have visualized isolated, negatively stained thick filaments from scorpion striated muscle. We modified the iterative helical real space reconstruction (IHRSR) method to include filament tilt, and band-pass filtered the aligned segments before averaging, achieving a 3.3 nm resolution 3D-reconstruction. This reconstruction revealed the presence of the myosin interacting-heads motif (adding to evidence that is widely spread), together with 12 subfilaments in the filament backbone. This demonstrates that conventional negative staining and imaging can be used to detect the presence of the myosin interacting-heads motif in helically ordered thick filaments from different species and muscle types, thus avoiding the use of less accessible cryo-EM and low electron-dose procedures. PMID:22982253

  12. ZASP Interacts with the Mechanosensing Protein Ankrd2 and p53 in the Signalling Network of Striated Muscle

    PubMed Central

    Martinelli, Valentina C.; Kyle, W. Buck; Kojic, Snezana; Vitulo, Nicola; Li, Zhaohui; Belgrano, Anna; Maiuri, Paolo; Banks, Lawrence; Vatta, Matteo; Valle, Giorgio; Faulkner, Georgine

    2014-01-01

    ZASP is a cytoskeletal PDZ-LIM protein predominantly expressed in striated muscle. It forms multiprotein complexes and plays a pivotal role in the structural integrity of sarcomeres. Mutations in the ZASP protein are associated with myofibrillar myopathy, left ventricular non-compaction and dilated cardiomyopathy. The ablation of its murine homologue Cypher results in neonatal lethality. ZASP has several alternatively spliced isoforms, in this paper we clarify the nomenclature of its human isoforms as well as their dynamics and expression pattern in striated muscle. Interaction is demonstrated between ZASP and two new binding partners both of which have roles in signalling, regulation of gene expression and muscle differentiation; the mechanosensing protein Ankrd2 and the tumour suppressor protein p53. These proteins and ZASP form a triple complex that appears to facilitate poly-SUMOylation of p53. We also show the importance of two of its functional domains, the ZM-motif and the PDZ domain. The PDZ domain can bind directly to both Ankrd2 and p53 indicating that there is no competition between it and p53 for the same binding site on Ankrd2. However there is competition for this binding site between p53 and a region of the ZASP protein lacking the PDZ domain, but containing the ZM-motif. ZASP is negative regulator of p53 in transactivation experiments with the p53-responsive promoters, MDM2 and BAX. Mutations in the ZASP ZM-motif induce modification in protein turnover. In fact, two mutants, A165V and A171T, were not able to bind Ankrd2 and bound only poorly to alpha-actinin2. This is important since the A165V mutation is responsible for zaspopathy, a well characterized autosomal dominant distal myopathy. Although the mechanism by which this mutant causes disease is still unknown, this is the first indication of how a ZASP disease associated mutant protein differs from that of the wild type ZASP protein. PMID:24647531

  13. Complementary global maps for orientation coding in upper and lower layers of the monkey's foveal striate cortex.

    PubMed

    Bauer, R; Dow, B M

    1989-01-01

    A population of 269 cells recorded from the foveal representation of striate cortex in 2 rhesus macaque monkeys was examined for orientation preference as a function of receptive field position relative to the center of gaze. Cells recorded in supragranular and infragranular layers were segregated and compared. Within the foveolar region (0.0-0.5 degrees) supragranular cells showed a vertical bias which was not evident in the infragranular layers. At larger eccentricities (0.5-2.5 degrees) supragranular cells showed a radial bias (preferred orientation points toward the center of gaze), whereas infragranular cells showed a concentric bias (preferred orientation is tangent to a circle around the center of gaze). These results are consistent with our earlier report of an orientation shift between the supragranular and infragranular layers (Bauer et al. 1980, 1983; Dow and Bauer 1984). The diagonal orientation bias which we noted earlier (Bauer et al. 1980; Dow and Bauer 1984) in supragranular cells at eccentricities between 0.5 and 2.5 degrees can be explained by the radial bias, combined with a tendency for recording sites to favor receptive field locations closer to the diagonal meridia than to either the horizontal or vertical meridia. Given other evidence that upper layer cells in macaque striate cortex tend to show either orientation or color selectivity, while lower layer cells tend to show movement sensitivity (Dow 1974; Livingstone and Hubel 1984), the present data suggest a functional dichotomy between a supragranular system involved in fixational eye movements and pattern vision and an infragranular system activated primarily by optical flow fields during ambulation. PMID:2792244

  14. Geologic continuous casting below continental and deep-sea detachment faults and at the striated extrusion of Sacsayhuaman, Peru

    USGS Publications Warehouse

    Spencer, J.E.

    1999-01-01

    In the common type of industrial continuous casting, partially molten metal is extruded from a vessel through a shaped orifice called a mold in which the metal assumes the cross-sectional form of the mold as it cools and solidifies. Continuous casting can be sustained as long as molten metal is supplied and thermal conditions are maintained. I propose that a similar process produced parallel sets of grooves in three geologic settings, as follows: (1) corrugated metamorphic core complexes where mylonized mid-crustal rocks were exhumed by movement along low-angle normal faults known as detachment faults; (2) corrugated submarine surfaces where ultramafic and mafic rocks were exhumed by normal faulting within oceanic spreading centers; and (3) striated magma extrusions exemplified by the famous grooved outcrops at the Inca fortress of Sacsayhuaman in Peru. In each case, rocks inferred to have overlain the corrugated surface during corrugation genesis molded and shaped a plastic to partially molten rock mass as it was extruded from a moderate- to high-temperature reservoir.

  15. Correction of multiple striated muscles in murine Pompe disease through adeno-associated virus-mediated gene therapy.

    PubMed

    Sun, Baodong; Young, Sarah P; Li, Ping; Di, Chunhui; Brown, Talmage; Salva, Maja Z; Li, Songtao; Bird, Andrew; Yan, Zhen; Auten, Richard; Hauschka, Stephen D; Koeberl, Dwight D

    2008-08-01

    Glycogen storage disease type II (Pompe disease; MIM 232300) stems from the deficiency of acid alpha-glucosidase (GAA; acid maltase; EC 3.2.1.20), which primarily involves cardiac and skeletal muscles. An adeno-associated virus 2/8 (AAV2/8) vector containing the muscle creatine kinase (MCK) (CK1) reduced glycogen content by approximately 50% in the heart and quadriceps in GAA-knockout (GAA-KO) mice; furthermore, an AAV2/8 vector containing the hybrid alpha-myosin heavy chain enhancer-/MCK enhancer-promoter (MHCK7) cassette reduced glycogen content by >95% in heart and >75% in the diaphragm and quadriceps. Transduction with an AAV2/8 vector was higher in the quadriceps than in the gastrocnemius. An AAV2/9 vector containing the MHCK7 cassette corrected GAA deficiency in the distal hindlimb, and glycogen accumulations were substantially cleared by human GAA (hGAA) expression therein; however, the analogous AAV2/7 vector achieved much lower efficacy. Administration of the MHCK7-containing vectors significantly increased striated muscle function as assessed by increased Rotarod times at 18 weeks after injection, whereas the CK1-containing vector did not increase Rotarod performance. Importantly, type IIb myofibers in the extensor digitalis longus (EDL) were transduced, thereby correcting a myofiber type that is unresponsive to enzyme replacement therapy. In summary, AAV8 and AAV9-pseudotyped vectors containing the MHCK7 regulatory cassette achieved enhanced efficacy in Pompe disease mice. PMID:18560415

  16. Overexpression of Striated Muscle Activator of Rho Signaling (STARS) Increases C2C12 Skeletal Muscle Cell Differentiation

    PubMed Central

    Wallace, Marita A.; Della Gatta, Paul A.; Ahmad Mir, Bilal; Kowalski, Greg M.; Kloehn, Joachim; McConville, Malcom J.; Russell, Aaron P.; Lamon, Séverine

    2016-01-01

    Background: Skeletal muscle growth and regeneration depend on the activation of satellite cells, which leads to myocyte proliferation, differentiation and fusion with existing muscle fibers. Skeletal muscle cell proliferation and differentiation are tightly coordinated by a continuum of molecular signaling pathways. The striated muscle activator of Rho signaling (STARS) is an actin binding protein that regulates the transcription of genes involved in muscle cell growth, structure and function via the stimulation of actin polymerization and activation of serum-response factor (SRF) signaling. STARS mediates cell proliferation in smooth and cardiac muscle models; however, whether STARS overexpression enhances cell proliferation and differentiation has not been investigated in skeletal muscle cells. Results: We demonstrate for the first time that STARS overexpression enhances differentiation but not proliferation in C2C12 mouse skeletal muscle cells. Increased differentiation was associated with an increase in the gene levels of the myogenic differentiation markers Ckm, Ckmt2 and Myh4, the differentiation factor Igf2 and the myogenic regulatory factors (MRFs) Myf5 and Myf6. Exposing C2C12 cells to CCG-1423, a pharmacological inhibitor of SRF preventing the nuclear translocation of its co-factor MRTF-A, had no effect on myotube differentiation rate, suggesting that STARS regulates differentiation via a MRTF-A independent mechanism. Conclusion: These findings position STARS as an important regulator of skeletal muscle growth and regeneration. PMID:26903873

  17. Dietary fish oil blocks the microcirculatory manifestations of ischemia-reperfusion injury in striated muscle in hamsters.

    PubMed Central

    Lehr, H A; Hübner, C; Nolte, D; Kohlschütter, A; Messmer, K

    1991-01-01

    Epidemiologic observations and experimental studies have demonstrated a protective effect of dietary fish oil on the clinical manifestations of ischemia-reperfusion injury. To investigate the underlying mechanisms, we used the dorsal skinfold chamber model for intravital fluorescence microscopy of the microcirculation in striated muscle of awake hamsters. In control hamsters (n = 7), reperfusion after a 4-hr pressure-induced ischemia to the muscle tissue elicited the adhesion of fluorescently stained leukocytes to the endothelium of postcapillary venules, capillary obstruction, and the break-down of endothelial integrity. These microvascular manifestations of ischemia-reperfusion injury were significantly attenuated in animals (n = 7) when fed with a fish oil-enriched diet for 4 weeks prior to the experiments. In leukocyte total lipids, the fish oil diet resulted in a substantial displacement of arachidonic acid, the precursor of the potent adhesion-promoting leukotriene (LT) B4, by fish oil-derived eicosapentaenoic acid, the precursor of biologically less potent LTB5, emphasizing the mediator role of LTB4 in ischemia-reperfusion injury. These results suggest that the preservation of microvascular perfusion by dietary fish oil contributes to its protective effects on the clinical manifestations of ischemia-reperfusion injury. PMID:1650479

  18. The “Goldilocks Zone” from a redox perspective—Adaptive vs. deleterious responses to oxidative stress in striated muscle

    PubMed Central

    Alleman, Rick J.; Katunga, Lalage A.; Nelson, Margaret A. M.; Brown, David A.; Anderson, Ethan J.

    2014-01-01

    Consequences of oxidative stress may be beneficial or detrimental in physiological systems. An organ system's position on the “hormetic curve” is governed by the source and temporality of reactive oxygen species (ROS) production, proximity of ROS to moieties most susceptible to damage, and the capacity of the endogenous cellular ROS scavenging mechanisms. Most importantly, the resilience of the tissue (the capacity to recover from damage) is a decisive factor, and this is reflected in the disparate response to ROS in cardiac and skeletal muscle. In myocytes, a high oxidative capacity invariably results in a significant ROS burden which in homeostasis, is rapidly neutralized by the robust antioxidant network. The up-regulation of key pathways in the antioxidant network is a central component of the hormetic response to ROS. Despite such adaptations, persistent oxidative stress over an extended time-frame (e.g., months to years) inevitably leads to cumulative damages, maladaptation and ultimately the pathogenesis of chronic diseases. Indeed, persistent oxidative stress in heart and skeletal muscle has been repeatedly demonstrated to have causal roles in the etiology of heart disease and insulin resistance, respectively. Deciphering the mechanisms that underlie the divergence between adaptive and maladaptive responses to oxidative stress remains an active area of research for basic scientists and clinicians alike, as this would undoubtedly lead to novel therapeutic approaches. Here, we provide an overview of major types of ROS in striated muscle and the divergent adaptations that occur in response to them. Emphasis is placed on highlighting newly uncovered areas of research on this topic, with particular focus on the mitochondria, and the diverging roles that ROS play in muscle health (e.g., exercise or preconditioning) and disease (e.g., cardiomyopathy, ischemia, metabolic syndrome). PMID:25278906

  19. Structure and interactions of the carboxyl terminus of striated muscle alpha-tropomyosin: it is important to be flexible.

    PubMed Central

    Greenfield, Norma J; Palm, Thomas; Hitchcock-DeGregori, Sarah E

    2002-01-01

    Tropomyosin (TM) binds to and regulates the actin filament. We used circular dichroism and heteronuclear NMR to investigate the secondary structure and interactions of the C terminus of striated muscle alpha-TM, a major functional determinant, using a model peptide, TM9a(251-284). The (1)H(alpha) and (13)C(alpha) chemical shift displacements show that residues 252 to 277 are alpha-helical but residues 278 to 284 are nonhelical and mobile. The (1)H(N) and (13)C' displacements suggest that residues 257 to 269 form a coiled coil. Formation of an "overlap" binary complex with a 33-residue N-terminal chimeric peptide containing residues 1 to 14 of alpha-TM perturbs the (1)H(N) and (15)N resonances of residues 274 to 284. Addition of a fragment of troponin T, TnT(70-170), to the binary complex perturbs most of the (1)H(N)-(15)N cross-peaks. In addition, there are many new cross-peaks, showing that the binding is asymmetric. Q263, in a proposed troponin T binding site, shows two sets of side-chain (15)N-(1)H cross-peaks, indicating conformational flexibility. The conformational equilibrium of the side chain changes upon formation of the binary and ternary complexes. Replacing Q263 with leucine greatly increases the stability of TM9a(251-284) and reduces its ability to form the binary and ternary complexes, showing that conformational flexibility is crucial for the binding functions of the C terminus. PMID:12414708

  20. Correction of Multiple Striated Muscles in Murine Pompe Disease Through Adeno-associated Virus-Mediated Gene Therapy

    PubMed Central

    Sun, Baodong; Young, Sarah P.; Li, Ping; Di, Chunhui; Brown, Talmage; Salva, Maia Z.; Li, Songtao; Bird, Andrew; Yan, Zhen; Auten, Richard; Hauschka, Stephen D.; Koeberl, Dwight D.

    2009-01-01

    Glycogen storage disease type II (GSD-II; Pompe disease; MIM 232300) stems from the deficiency of acid-α-glucosidase (GAA; acid maltase; EC 3.2.1.20), which primarily involves cardiac and skeletal muscles. We hypothesized that systemic administration of an adeno-associated virus (AAV) vector containing a muscle specific regulatory cassette could drive efficacious transgene expression in GAA-knockout (GAA-KO) mice. AAV2/8 vectors containing the muscle creatine kinase (CK1) or hybrid α-myosin heavy chain enhancer-/muscle creatine kinase enhancer-promoter (MHCK7) cassettes were compared. The CK1 reduced glycogen content by approximately 50% in the heart and quadriceps, in comparison to untreated GAA-KO mice, whereas the MHCK7 containing vector reduced glycogen content even further: >95% in heart and >75% in the diaphragm and quadriceps. Administration of the MHCK7-containing vector significantly increased striated muscle function as assessed by increased Rotarod times at 18 weeks post-injection, whereas the CK1-containing vector did not increase Rotarod performance. Transduction efficiency was evaluated with an AAV2/8 vector in which MHCK7 drives alkaline-phosphatase, revealing that many more myofibers were transduced in the quadriceps than in the gastrocnemius. An AAV2/9 vector containing the MHCK7 cassette corrected GAA deficiency in the skeletal muscles of the distal limb, including the gastrocnemius, extensor digitalis longus, and soleus; furthermore, glycogen accumulations were substantially cleared by hGAA expression therein. Importantly, type IIb myofibers in the extensor digitalis longus were transduced, thereby correcting a myofiber type that is unresponsive to enzyme replacement therapy. In summary, AAV8 and AAV9-pseudotyped vectors containing the MHCK7 regulatory cassette achieved enhanced efficacy in Pompe disease mice. PMID:18560415

  1. (−)-EPICATECHIN IMPROVES MITOCHONDRIAL RELATED PROTEIN LEVELS AND AMELIORATES OXIDATIVE STRESS IN DYSTROPHIC DELTA SARCOGLYCAN NULL MOUSE STRIATED MUSCLE

    PubMed Central

    Ramirez-Sanchez, Israel; De los Santos, Sergio; Gonzalez-Basurto, Silvia; Canto, Patricia; Mendoza-Lorenzo, Patricia; Palma-Flores, Carlos; Ceballos-Reyes, Guillermo; Villarreal, Francisco; Zentella-Dehesa, Alejandro; Coral-Vazquez, Ramon

    2014-01-01

    Muscular dystrophies (MD) are a group of heterogeneous genetic disorders characterized by progressive striated muscle wasting and degeneration. Although the genetic basis for many of these disorders has been identified, the exact mechanism for disease pathogenesis remains unclear. The presence of oxidative stress (OS) is known to contribute to the pathophysiology and severity of the MD. Mitochondrial dysfunction is observed in MD and likely represents an important determinant of increased OS. Experimental antioxidant therapies have been implemented with the aim of protecting against disease progression, but results from clinical trials have been disappointing. In this study, we explored the capacity of the cacao flavonoid (−)-epicatechin (Epi) to mitigate OS by acting as a positive regulator of mitochondrial structure/function endpoints and redox balance control systems in skeletal and cardiac muscles of dystrophic, δ-sarcoglycan (δ-SG) null mice. Wild type or δ-SG null 2.5 month old male mice were treated via oral gavage with either water (control animals) or Epi (1 mg/kg, twice/day) for 2 weeks. Results evidence a significant normalization of total protein carbonylation, recovery of reduced/oxidized glutathione (GSH/GSSG ratio) and enhanced superoxide dismutase 2, catalase and citrate synthase activities with Epi treatment. These effects were accompanied by increases in protein levels for thiolredoxin, glutathione peroxidase, superoxide dismutase 2, catalase and mitochondrial endpoints. Furthermore, we evidence decreases in heart and skeletal muscle fibrosis, accompanied with an improvement in skeletal muscle function with treatment. These results warrant the further investigation of Epi as a potential therapeutic agent to mitigate MD associated muscle degeneration. PMID:25284161

  2. Development of Trichosomoides nasalis (Nematoda: Trichinelloidea) in the murid host: evidence for larval growth in striated muscle fibres

    PubMed Central

    Fall, E.H.; Diagne, M.; Junker, K.; Duplantier, J.M.; Ba, K.; Vallée, I.; Bain, O.

    2012-01-01

    Trichosomoides nasalis (Trichinelloidea) is a parasite of Arvicanthis niloticus (Muridae) in Senegal. Female worms that harbour dwarf males in their uteri, occur in the epithelium of the nasal mucosa. Young laboratory-bred A. niloticus were either fed females containing larvated eggs or intraperitoneally injected with motile first-stage larvae recovered from female uteri. Both resulted in successful infection. Organs examined during rodent necropsy were blood and lymphatic circulatory systems (heart, large vessels, lymphnodes), lungs, liver, kidneys, thoracic and abdominal cavities, thoracic and abdominal muscular walls, diaphragm, tongue, and nasal mucosa. Development to adult nasal stages took three weeks. Recovery of newly hatched larvae from the peritoneal fluid at four-eight hours after oral infection suggests a direct passage from the stomach or intestinal wall to the musculature. However, dissemination through the blood, as observed with Trichinella spiralis, cannot be excluded even though newly hatched larvae of T. nasalis are twice as thick (15 μm). Developing larvae were found in histological sections of the striated muscle of the abdominal and thoracic walls, and larvae in fourth moult were dissected from these sites. Adult females were found in the deep nasal mucosa where mating occurred prior to worms settling in the nasal epithelium. The present study shows a remarkable similarity between T. nasalis and Trichinella species regarding muscle tropism, but the development of T. nasalis is not arrested at the late first-larval stage and does not induce transformation of infected fibres into nurse cells. T. nasalis seems a potential model to study molecular relations between trichinelloid larvae and infected muscle fibres. PMID:22314237

  3. (-)-Epicatechin improves mitochondrial-related protein levels and ameliorates oxidative stress in dystrophic δ-sarcoglycan null mouse striated muscle.

    PubMed

    Ramirez-Sanchez, Israel; De los Santos, Sergio; Gonzalez-Basurto, Silvia; Canto, Patricia; Mendoza-Lorenzo, Patricia; Palma-Flores, Carlos; Ceballos-Reyes, Guillermo; Villarreal, Francisco; Zentella-Dehesa, Alejandro; Coral-Vazquez, Ramon

    2014-12-01

    Muscular dystrophies (MDs) are a group of heterogeneous genetic disorders characterized by progressive striated muscle wasting and degeneration. Although the genetic basis for many of these disorders has been identified, the exact mechanism of disease pathogenesis remains unclear. The presence of oxidative stress (OS) is known to contribute to the pathophysiology and severity of the MD. Mitochondrial dysfunction is observed in MD, and probably represents an important determinant of increased OS. Experimental antioxidant therapies have been implemented with the aim of protecting against disease progression, but results from clinical trials have been disappointing. In this study, we explored the capacity of the cacao flavonoid (-)-epicatechin (Epi) to mitigate OS by acting as a positive regulator of mitochondrial structure/function endpoints and redox balance control systems in skeletal and cardiac muscles of dystrophic, δ-sarcoglycan (δ-SG) null mice. Wild-type or δ-SG null 2.5-month-old male mice were treated via oral gavage with either water (controls) or Epi (1 mg·kg(-1) , twice daily) for 2 weeks. The results showed significant normalization of total protein carbonylation, recovery of the glutathione/oxidized glutathione ratio and enhanced superoxide dismutase 2, catalase and citrate synthase activities with Epi treatment. These effects were accompanied by increases in the protein levels of thioredoxin, glutathione peroxidase, superoxide dismutase 2, catalase, and mitochondrial endpoints. Furthermore, we found decreases in heart and skeletal muscle fibrosis, accompanied by an improvement in skeletal muscle function, with treatment. These results warrant further investigation of Epi as a potential therapeutic agent to mitigate MD-associated muscle degeneration. PMID:25284161

  4. Sensory and autonomic neurons project both to the smooth retractor penis and to the striated bulbospongiosus muscles. Neurochemical features of the sympathetic subset.

    PubMed

    Botti, Maddalena; Gazza, Ferdinando; Ragionieri, Luisa; Minelli, Luisa Bo; Panu, Rino

    2012-08-01

    Aim of the present study was to verify, by means of double retrograde neuronal tracers technique, the hypothesis that a subpopulation of sensory and autonomic neurons send collateral axons to both smooth and striated genital muscles. We also wanted to define the neurochemical content of the eventually retrogradelly double labeled (RDL) neurons in the sympathetic trunk ganglia (STG). We used six intact pigs and we injected the tracer Diamidino Yellow (DY) in the smooth left retractor penis muscle (RPM) and the tracer Fast Blue (FB) in the striated left bulbospongiosus muscle (BSM). Rare (2 ± 0.6) RDL neurons were found in the ipsilateral S2 spinal ganglion (SG), 220 ± 42 in the ipsilateral STGs, from L3 to S3, 19 ± 15 in the contralateral S1-S2 ones and 22 ± 5 in the bilateral caudal mesenteric ganglia (CMG). The RDL neurons of the STG were IR for TH (85 ± 13%), DβH (69 ± 17%), NPY (69 ± 23%), nNOS (60 ± 11%), LENK (54 ± 19%), VIP (53±26%), SOM (40 ± 8%), CGRP (34 ± 12%), SP (31 ± 16%), and VAChT (28 ± 3%). Our research highlights the presence of sensory and sympathetic neurons with qualitatively different neurochemical content sending axons both to the smooth RPM and to the striated BSM of the pig. These RDL neurons are likely to project to the smooth vasal musculature to create the ideal physiological conditions in which these muscles can optimize the erectile function. PMID:22707224

  5. Computer analysis between nucleotide and amino acid sequences of bean golden mosaic virus and those of maize streak, wheat dwarf, chloris striate mosaic, and beet curly top viruses.

    PubMed

    Ikegami, M

    1989-01-01

    Bean golden mosaic virus (BGMV) DNA 1 and 2 have little sequence homology with maize streak virus (MSV), wheat dwarf virus (WDV), and chloris striate mosaic virus (CSMV) DNAs. BGMV DNA 1 and beet curly top virus (BCTV) DNA are closely related, whereas BGMV DNA 2 and BCTV DNA are not related. Direct amino acid homologies of predicted proteins between BGMV ORFs and MSV ORFs, WDV ORFs or CSMV ORFs were 40-50%. BGMV 1L1 and BCTV L1, and BGMV IL3 and BCTV L4 were highly conserved. The sequence TAATATTAC was detected in the loops of hairpin structures of 5 gemini-viruses. PMID:2615677

  6. Changes in Late Cretaceous-Quaternary Caribbean plate motion directions inferred from paleostress measurements from striated fault planes

    NASA Astrophysics Data System (ADS)

    Batbayar, K.; Mann, P.; Hippolyte, J.

    2013-12-01

    We compiled paleostress analyses from previous research works collected at 591 localities of striated fault planes in rocks ranging in age from Late Cretaceous to Quaternary in the circum-Caribbean and Mexico. The purpose of the study is to quantify a progressive clockwise rotation of the Caribbean plate during its Late Cretaceous to recent subduction of the Proto-Caribbean seaway. Paleostress analysis is based on the assumption that slickenside lineations indicate both the direction and sense of maximum resolved shear stress on that fault plane. We have plotted directions of maximum horizontal stress onto plate tectonic reconstructions of the circum-Caribbean plate boundaries and infer that these directions are proxies for paleo-plate motion directions of the Caribbean plate. Plotting these stress directions onto reconstructions provided a better visualization of the relation of stress directions to blocks at their time of Late Cretaceous to recent deformation. Older, more deformed rocks of Late Cretaceous to Eocene ages yield a greater scatter in derived paleostress directions as these rocks have steeper dips, more pervasive faulting, and were likely affected by large rotations as known from previous paleomagnetic studies of Caribbean plate margins. Despite more scatter in measurements from older rock units, four major events that affected the Caribbean plate and the Great Arc of the Caribbean (GAC) are recognizable from changing orientations of stress directions: 1) Late Cretaceous collision of the GAC with southern Mexico and Colombia is consistent with NE directions of maximum compression in rocks of this age range in southern Mexico and EW directions in Colombia as the GAC approached the Proto-Caribbean seaway; 2) Paleocene-Eocene collision of the GAC with the Bahamas platform in Cuba and Hispaniola and with the South American plate in Venezuela is consistent with CW rotations of stress directions in rocks of these ages in the northern Caribbean and CCW

  7. Chronic recordings from single sites of kitten striate cortex during experience-dependent modifications of receptive-field properties.

    PubMed

    Mioche, L; Singer, W

    1989-07-01

    1. With the use of chronically implanted floating microelectrodes, we obtained simultaneous single-unit recordings from multiple sites in the kitten striate cortex and followed experience-dependent modifications of receptive-field properties. For induction of experimental modifications, we used the paradigm of monocular deprivation and reverse occlusion. Kittens were implanted when 4-5 wk old. During the following 2 days, receptive-field properties of the recorded units were determined once under light ketamine anesthesia and repeatedly while the kittens were awake and only lightly restrained. Subsequently, one eye was patched, and the resulting changes in neuronal eye preference were followed by repeated measurements of response properties. For investigation of the effects of reverse occlusion, the deprived eye was opened and the previously open eye closed when the neurons had become unresponsive to the initially deprived eye. Alternatively, kittens were monocularly deprived for 1 wk by lid suture before implantation. The closed eye was then opened, the other eye patched, and the effects of reverse occlusion were studied for up to 1 wk by repeated measurements of receptive-field properties. 2. The earliest effect of monocular deprivation was the disappearance of binocular summation, i.e., binocular responses ceased to be superior over monocular responses. Overt changes of ocular dominance were observed as early as 6 h after the beginning of monocular deprivation. These consisted of a gradual decrease of the excitatory response to deprived eye stimulation and, on occasions, of an additional moderate increase of responses to the normal eye. A complete loss of excitatory responses to deprived-eye stimulation was seen as early as 12 h after occlusion. In numerous cells, however, stimulation of the deprived eye continued to evoke inhibitory responses even after excitatory responses had vanished completely. During this shift in ocularity, neurons preserved their

  8. Reticulated, Hyperchromic Rash in a Striated Pattern Mimicking Atopic Dermatitis and Fungal Infection in a 2-Month-Old Female: A Case of Incontinentia Pigmenti

    PubMed Central

    Poliak, Nina; Le, Alexandre; Rainey, Anthony

    2016-01-01

    We present a 12-month-old Hispanic female with a reticulated, hyperchromic rash in a striated pattern appearing on upper and lower extremities and trunk and back since the age of 6 weeks. Over the next 10 months, the rash persisted. The rash did not respond to treatment with antifungals and steroids. During her 6-month wellness visit, the patient was diagnosed with incontinentia pigmenti (IP), a rare X-linked dominant disorder, fatal to male fetuses in utero. IP can lead to serious neurological and ophthalmologic consequences. Early diagnosis by primary care physicians and parental education about the condition are essential for prevention of retinal detachment, developmental delay, and dental abnormalities. PMID:27195166

  9. Three-dimensional structure of the M-region (bare zone) of vertebrate striated muscle myosin filaments by single-particle analysis.

    PubMed

    Al-Khayat, Hind A; Kensler, Robert W; Morris, Edward P; Squire, John M

    2010-11-12

    The rods of anti-parallel myosin molecules overlap at the centre of bipolar myosin filaments to produce an M-region (bare zone) that is free of myosin heads. Beyond the M-region edges, myosin molecules aggregate in a parallel fashion to yield the bridge regions of the myosin filaments. Adjacent myosin filaments in striated muscle A-bands are cross-linked by the M-band. Vertebrate striated muscle myosin filaments have a 3-fold rotational symmetry around their long axes. In addition, at the centre of the M-region, there are three 2-fold axes perpendicular to the filament long axis, giving the whole filament dihedral 32-point group symmetry. Here we describe the three-dimensional structure obtained by a single-particle analysis of the M-region of myosin filaments from goldfish skeletal muscle under relaxing conditions and as viewed in negative stain. This is the first single-particle reconstruction of isolated M-regions. The resulting three-dimensional reconstruction reveals details to about 55 Å resolution of the density distribution in the five main nonmyosin densities in the M-band (M6', M4', M1, M4 and M6) and in the myosin head crowns (P1, P2 and P3) at the M-region edges. The outermost crowns in the reconstruction were identified specifically by their close similarity to the corresponding crown levels in our previously published bridge region reconstructions. The packing of myosin molecules into the M-region structure is discussed, and some unidentified densities are highlighted. PMID:20851129

  10. Effects of the phlebotropic drug Daflon 500 mg on postischemic reperfusion injury in striated skin muscle: a histomorphologic study in the hamster.

    PubMed

    Pickelmann, S; Nolte, D; Leiderer, R; Möllmann, M; Schütze, E; Messmer, K

    1999-11-01

    The objective of this study was to investigate the effects of the purified, micronized, flavonoid fraction Daflon 500 mg (S 5682, 90% diosmin and 10% hesperidin) on tissue damage and leukocyte emigration in striated skin muscle after ischemia-reperfusion, as assessed by histomorphometric analysis. The experimental model used was the transparent dorsal skin fold chamber in the awake Syrian golden hamster. Sixty-four animals were randomly allotted to two treatment groups and time points of investigation. Animals were fed with 30 mg kg(-1) body weight Daflon 500 mg (n = 32) or its vehicle, 5% Arabic gum solution (n = 32), as control 8 hours before ischemia. Before induction of a tourniquet ischemia of 4 hours' duration and at 0.5, 2, and 24 hours of reperfusion, tissue sections were preserved for light and electron microscopic analysis (n = seven or eight animals per time point). The number of intravascular and extravascular leukocytes was determined by light microscopic analysis of esterase-positive leukocytes. For quantitative analysis of ischemia-induced endothelial cell damage, the endothelial thickness of capillaries was calculated by a computer-assisted imaging system, whereas the ischemic tissue damage was assessed by means of a score system (grade 0-3) by an independent investigator. The number of emigrated leukocytes was significantly reduced in Daflon 500 mg-treated animals compared with numbers found in control animals. The histomorphologic muscle fiber damage increased after reperfusion in both groups but was significantly reduced in the Daflon 500 mg-treated animals 2 and 24 hours after reperfusion. These results suggest that the emigration of leukocytes plays an important role in the development of postischemic reperfusion injury of striated skin muscle. PMID:10560948

  11. Isoform composition and gene expression of thick and thin filament proteins in striated muscles of mice after 30-day space flight.

    PubMed

    Ulanova, Anna; Gritsyna, Yulia; Vikhlyantsev, Ivan; Salmov, Nikolay; Bobylev, Alexander; Abdusalamova, Zarema; Rogachevsky, Vadim; Shenkman, Boris; Podlubnaya, Zoya

    2015-01-01

    Changes in isoform composition, gene expression of titin and nebulin, and isoform composition of myosin heavy chains as well as changes in titin phosphorylation level in skeletal (m. gastrocnemius, m. tibialis anterior, and m. psoas) and cardiac muscles of mice were studied after a 30-day-long space flight onboard the Russian spacecraft "BION-M" number 1. A muscle fibre-type shift from slow-to-fast and a decrease in the content of titin and nebulin in the skeletal muscles of animals from "Flight" group was found. Using Pro-Q Diamond staining, an ~3-fold increase in the phosphorylation level of titin in m. gastrocnemius of mice from the "Flight" group was detected. The content of titin and its phosphorylation level in the cardiac muscle of mice from "Flight" and "Control" groups did not differ; nevertheless an increase (2.2 times) in titin gene expression in the myocardium of flight animals was found. The observed changes are discussed in the context of their role in the contractile activity of striated muscles of mice under conditions of weightlessness. PMID:25664316

  12. Behaviour of the urethral striated sphincter and of the bladder in the chronic spinal cat. Implications at the Central Nervous System Level.

    PubMed

    Rampal, G; Mignard, P

    1975-01-01

    Nine cats were spinalized at the thoraco-lumbar junction (T12-L7) and the subsequent behaviour of the bladder and urethral striated sphincter was observed during periods of up to 27 days after spinalization by means of bladder manometry and of urethral electromyography. On the day following operation, the urethral sphincter responds to stimulation of its intact motor nerve, the pudic nerve by reflex (R) and direct (M) responses analogous to those of the intact animal anaesthetized with chloralose. The ratio R/M lies between 1 and 0.6 in the chronic spinal cat whereas it is generally less than 0.5 in the intact chloralose-anaesthetized cat. The tonic activity of the sphincter is weak or not present. The continence, however, is well maintained. The bladder activity appears only 4 to 8 days after spinalization. The bladder can thus void urine during brief contractions. These micturitions are always incomplete. The urethral reflex activity, either spontaneous or triggered by stimulation of the pudic nerve, may be inhibited, i: to a moderate degree by passive bladder distension; ii: almost completely by activation of vesicomotor neurones which provoke the bladder contraction. The first inhibition is seen the day after spinalization and is probably a protective reflex against vesical hypertension. The second inhibition develops progressively and in parallel to the functional recovery of vesical preganglionic neurones. It takes place on a background of antagnostic equilibrium of bladder and of urethral sphincter activities during micturition. PMID:1168331

  13. Geologic continuous casting below continental and deep-sea detachment faults and at the striated extrusion of Sacsayhuamán, Peru

    NASA Astrophysics Data System (ADS)

    Spencer, Jon E.

    1999-04-01

    In one common type of industrial continuous casting, partially molten metal is extruded from a vessel through a shaped orifice called a mold in which the metal assumes the cross-sectional form of the mold as it cools and solidifies. Continuous casting can be sustained as long as molten metal is supplied and thermal conditions are maintained. I propose that a similar process produced parallel sets of grooves in three geologic settings, as follows: (1) corrugated metamorphic core complexes where mylonitized mid-crustal rocks were exhumed by movement along low-angle normal faults known as detachment faults; (2) corrugated submarine surfaces where ultramafic and mafic rocks were exhumed by normal faulting within oceanic spreading centers; and (3) striated magma extrusions exemplified by the famous grooved outcrops at the Inca fortress of Sacsayhuamán in Peru. In each case, rocks inferred to have overlain the corrugated surface during corrugation genesis molded and shaped a plastic to partially molten rock mass as it was extruded from a moderate- to high-temperature reservoir.

  14. Isoform Composition and Gene Expression of Thick and Thin Filament Proteins in Striated Muscles of Mice after 30-Day Space Flight

    PubMed Central

    Ulanova, Anna; Gritsyna, Yulia; Vikhlyantsev, Ivan; Salmov, Nikolay; Bobylev, Alexander; Abdusalamova, Zarema; Rogachevsky, Vadim; Shenkman, Boris; Podlubnaya, Zoya

    2015-01-01

    Changes in isoform composition, gene expression of titin and nebulin, and isoform composition of myosin heavy chains as well as changes in titin phosphorylation level in skeletal (m. gastrocnemius, m. tibialis anterior, and m. psoas) and cardiac muscles of mice were studied after a 30-day-long space flight onboard the Russian spacecraft “BION-M” number 1. A muscle fibre-type shift from slow-to-fast and a decrease in the content of titin and nebulin in the skeletal muscles of animals from “Flight” group was found. Using Pro-Q Diamond staining, an ~3-fold increase in the phosphorylation level of titin in m. gastrocnemius of mice from the “Flight” group was detected. The content of titin and its phosphorylation level in the cardiac muscle of mice from “Flight” and “Control” groups did not differ; nevertheless an increase (2.2 times) in titin gene expression in the myocardium of flight animals was found. The observed changes are discussed in the context of their role in the contractile activity of striated muscles of mice under conditions of weightlessness. PMID:25664316

  15. Identification of striated muscle activator of Rho signaling (STARS) as a novel calmodulin target by a newly developed genome-wide screen.

    PubMed

    Furuya, Yusui; Denda, Miwako; Sakane, Kyohei; Ogusu, Tomoko; Takahashi, Sumio; Magari, Masaki; Kanayama, Naoki; Morishita, Ryo; Tokumitsu, Hiroshi

    2016-07-01

    To search for novel target(s) of the Ca(2+)-signaling transducer, calmodulin (CaM), we performed a newly developed genome-wide CaM interaction screening of 19,676 GST-fused proteins expressed in human. We identified striated muscle activator of Rho signaling (STARS) as a novel CaM target and characterized its CaM binding ability and found that the Ca(2+)/CaM complex interacted stoichiometrically with the N-terminal region (Ala13-Gln35) of STARS in vitro as well as in living cells. Mutagenesis studies identified Ile20 and Trp33 as the essential hydrophobic residues in CaM anchoring. Furthermore, the CaM binding deficient mutant (Ile20Ala, Trp33Ala) of STARS further enhanced its stimulatory effect on SRF-dependent transcriptional activation. These results suggest a connection between Ca(2+)-signaling via excitation-contraction coupling and the regulation of STARS-mediated gene expression in muscles. PMID:27132186

  16. A Novel Conserved Isoform of the Ubiquitin Ligase UFD2a/UBE4B Is Expressed Exclusively in Mature Striated Muscle Cells

    PubMed Central

    Mammen, Andrew L.; Mahoney, James A.; St. Germain, Amanda; Badders, Nisha; Taylor, J. Paul; Rosen, Antony; Spinette, Sarah

    2011-01-01

    Yeast Ufd2p was the first identified E4 multiubiquitin chain assembly factor. Its vertebrate homologues later referred to as UFD2a, UBE4B or E4B were also shown to have E3 ubiquitin ligase activity. UFD2a function in the brain has been well established in vivo, and in vitro studies have shown that its activity is essential for proper condensation and segregation of chromosomes during mitosis. Here we show that 2 alternative splice forms of UFD2a, UFD2a-7 and -7/7a, are expressed sequentially during myoblast differentiation of C2C12 cell cultures and during cardiotoxin-induced regeneration of skeletal muscle in mice. UFD2a-7 contains an alternate exon 7, and UFD2a-7/7a, the larger of the 2 isoforms, contains an additional novel exon 7a. Analysis of protein or mRNA expression in mice and zebrafish revealed that a similar pattern of isoform switching occurs during developmental myogenesis of cardiac and skeletal muscle. In vertebrates (humans, rodents, zebrafish), UFD2a-7/7a is expressed only in mature striated muscle. This unique tissue specificity is further validated by the conserved presence of 2 muscle-specific splicing regulatory motifs located in the 3′ introns of exons 7 and 7a. UFD2a interacts with VCP/p97, an AAA-type ATPase implicated in processes whose functions appear to be regulated, in part, through their interaction with one or more of 15 previously identified cofactors. UFD2a-7/7a did not interact with VCP/p97 in yeast 2-hybrid experiments, which may allow the ATPase to bind cofactors that facilitate its muscle-specific functions. We conclude that the regulated expression of these UFD2a isoforms most likely imparts divergent functions that are important for myogenisis. PMID:22174917

  17. Spectral sideband produced by a hemispherical concave multilayer on the African shield-bug Calidea panaethiopica (Scutelleridae)

    NASA Astrophysics Data System (ADS)

    Vigneron, Jean Pol; Ouedraogo, Moussa; Colomer, Jean-François; Rassart, Marie

    2009-02-01

    The African shield-backed bug Calidea panaethiopica is a very colorful insect which produces a range of iridescent yellow, green, and blue reflections. The cuticle of the dorsal side of the insect, on the shield, the prothorax and part of the head, is pricked of uniformly distributed hemispherical hollow cavities a few tens micrometers deep. Under normal illumination and viewing the insect’s muffin-tin shaped surface gives rise to two distinct colors: a yellow spot arising from the bottom of the well and a blue annular cloud that appears to float around the yellow spot. This effect is explained by multiple reflections on a hemispherical Bragg mirror with a mesoscopic curvature. A multiscale computing methodology was found to be needed to evaluate the reflection spectrum for such a curved multilayer. This multiscale approach is very general and should be useful for dealing with visual effects in many natural and artificial systems.

  18. Hyperactivation of L-type voltage-gated Ca2+ channels in Caenorhabditis elegans striated muscle can result from point mutations in the IS6 or the IIIS4 segment of the α1 subunit.

    PubMed

    Lainé, Viviane; Ségor, Jean Rony; Zhan, Hong; Bessereau, Jean-Louis; Jospin, Maelle

    2014-11-01

    Several human diseases, including hypokalemic periodic paralysis and Timothy syndrome, are caused by mutations in voltage-gated calcium channels. The effects of these mutations are not always well understood, partially because of difficulties in expressing these channels in heterologous systems. The use of Caenorhabditis elegans could be an alternative approach to determine the effects of mutations on voltage-gated calcium channel function because all the main types of voltage-gated calcium channels are found in C. elegans, a large panel of mutations already exists and efficient genetic tools are available to engineer customized mutations in any gene. In this study, we characterize the effects of two gain-of-function mutations in egl-19, which encodes the L-type calcium channel α1 subunit. One of these mutations, ad695, leads to the replacement of a hydrophobic residue in the IIIS4 segment. The other mutation, n2368, changes a conserved glycine of IS6 segment; this mutation has been identified in patients with Timothy syndrome. We show that both egl-19 (gain-of-function) mutants have defects in locomotion and morphology that are linked to higher muscle tone. Using in situ electrophysiological approaches in striated muscle cells, we provide evidence that this high muscle tone is due to a shift of the voltage dependency towards negative potentials, associated with a decrease of the inactivation rate of the L-type Ca(2+) current. Moreover, we show that the maximal conductance of the Ca(2+) current is decreased in the strongest mutant egl-19(n2368), and that this decrease is correlated with a mislocalization of the channel. PMID:25214488

  19. Spectroscopic and ITC study of the conformational change upon Ca{sup 2+}-binding in TnC C-lobe and TnI peptide complex from Akazara scallop striated muscle

    SciTech Connect

    Yumoto, Fumiaki; Tanaka, Hiroyuki; Nagata, Koji; Miyauchi, Yumiko; Miyakawa, Takuya; Ojima, Takao; Tanokura, Masaru

    2008-04-25

    Akazara scallop (Chlamys nipponensis akazara) troponin C (TnC) of striated adductor muscle binds only one Ca{sup 2+} ion at the C-terminal EF-hand motif (Site IV), but it works as the Ca{sup 2+}-dependent regulator in adductor muscle contraction. In addition, the scallop troponin (Tn) has been thought to regulate muscle contraction via activating mechanisms that involve the region spanning from the TnC C-lobe (C-lobe) binding site to the inhibitory region of the TnI, and no alternative binding of the TnI C-terminal region to TnC because of no similarity between second TnC-binding regions of vertebrate and the scallop TnIs. To clarify the Ca{sup 2+}-regulatory mechanism of muscle contraction by scallop Tn, we have analyzed the Ca{sup 2+}-binding properties of the complex of TnC C-lobe and TnI peptide, and their interaction using isothermal titration microcalorimetry, nuclear magnetic resonance, circular dichroism, and gel filtration chromatography. The results showed that single Ca{sup 2+}-binding to the Site IV leads to a structural transition not only in Site IV but also Site III through the structural network in the C-lobe of scallop TnC. We therefore assumed that the effect of Ca{sup 2+}-binding must lead to a change in the interaction mode between the C-lobe of TnC and the TnI peptide. The change should be the first event of the transmission of Ca{sup 2+} signal to TnI in Tn ternary complex.

  20. Mapping striate and extrastriate visual areas in human cerebral cortex.

    PubMed Central

    DeYoe, E A; Carman, G J; Bandettini, P; Glickman, S; Wieser, J; Cox, R; Miller, D; Neitz, J

    1996-01-01

    Functional magnetic resonance imaging (fMRI) was used to identify and map the representation of the visual field in seven areas of human cerebral cortex and to identify at least two additional visually responsive regions. The cortical locations of neurons responding to stimulation along the vertical or horizontal visual field meridia were charted on three-dimensional models of the cortex and on unfolded maps of the cortical surface. These maps were used to identify the borders among areas that would be topographically homologous to areas V1, V2, V3, VP, and parts of V3A and V4 of the macaque monkey. Visually responsive areas homologous to the middle temporal/medial superior temporal area complex and unidentified parietal visual areas were also observed. The topography of the visual areas identified thus far is consistent with the organization in macaque monkeys. However, these and other findings suggest that human and simian cortical organization may begin to differ in extrastriate cortex at, or beyond, V3A and V4. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8637882

  1. Statistical methods for the forensic analysis of striated tool marks

    SciTech Connect

    Hoeksema, Amy Beth

    2013-01-01

    In forensics, fingerprints can be used to uniquely identify suspects in a crime. Similarly, a tool mark left at a crime scene can be used to identify the tool that was used. However, the current practice of identifying matching tool marks involves visual inspection of marks by forensic experts which can be a very subjective process. As a result, declared matches are often successfully challenged in court, so law enforcement agencies are particularly interested in encouraging research in more objective approaches. Our analysis is based on comparisons of profilometry data, essentially depth contours of a tool mark surface taken along a linear path. In current practice, for stronger support of a match or non-match, multiple marks are made in the lab under the same conditions by the suspect tool. We propose the use of a likelihood ratio test to analyze the difference between a sample of comparisons of lab tool marks to a field tool mark, against a sample of comparisons of two lab tool marks. Chumbley et al. (2010) point out that the angle of incidence between the tool and the marked surface can have a substantial impact on the tool mark and on the effectiveness of both manual and algorithmic matching procedures. To better address this problem, we describe how the analysis can be enhanced to model the effect of tool angle and allow for angle estimation for a tool mark left at a crime scene. With sufficient development, such methods may lead to more defensible forensic analyses.

  2. Charge movement in the membrane of striated muscle.

    PubMed Central

    Adrian, R H; Almers, W

    1976-01-01

    1. Non-linear polarization currents apparently due to permanent dipoles or mobile charges in the membrane can be measured by appropriate comparison of the transient currents required to produce small and large steps of membrane potential. Integration of these transient polarization currents estimates the charge transfer associated with the movement of membrane dipoles or charges. 2. Depolarization from -100 to 0 mV requires a charge transfer of 35 nC/muF in addition to the charge transfer predicted by linear extrapolation of the charge required for a small depolarization from -100 mV. Depolarizations of varying size give a charge-voltage relation which is sigmoid saturating beyond o mV and with a midpoint at about -50 mV. The ratnged depolarization reduces or removes charge movement detected by comparing currents for small and large voltage steps from -100 mV (Charge 1). However in depolarized fibres comparison of currents from a small potential step at +40 mV and a large hyperpolarizing potential step from -20 mV reveals large movements of a second charge (Charge 2). Movement of Charge 2 is less steeply dependent on voltage than movement of Charge 2 both in magnitude and in rate. 4. In size and voltage dependence these two kinds of charge movement correspond to measured voltage dependence of capacity in normally polarized and depolarized fibres (Adrian & Almers, 1976). PMID:1082509

  3. Striated Muscle as Implantation Site for Transplanted Pancreatic Islets

    PubMed Central

    Espes, Daniel; Eriksson, Olof; Lau, Joey; Carlsson, Per-Ola

    2011-01-01

    Islet transplantation is an attractive treatment for selected patients with brittle type 1 diabetes. In the clinical setting, intraportal transplantation predominates. However, due to extensive early islet cell death, the quantity of islets needed to restore glucose homeostasis requires in general a minimum of two donors. Moreover, the deterioration of islet function over time results in few insulin-independent patients after five-year followup. Specific obstacles to the success of islet transplantation include site-specific concerns for the liver such as the instant blood mediated inflammatory reaction, islet lipotoxicity, low oxygen tension, and poor revascularization, impediments that have led to the developing interest for alternative implantation sites over recent years. Within preclinical settings, several alternative sites have now been investigated and proven favorable in various aspects. Muscle is considered a very promising site and has physiologically properties and technical advantages that could make it optimal for islet transplantation. PMID:22174984

  4. Ontogenesis of receptive fields in the rabbit striate cortex

    NASA Technical Reports Server (NTRS)

    Mathers, L. H.; Chow, K. L.; Spear, P. D.; Grobstein, P.

    1974-01-01

    The development of receptive fields in rabbit pups was investigated by measuring their responses to various light stimuli and to electric shock delivered to the optic nerve head. The pups ranged in age from three to twenty-five days, allowing correlation of findings with maturation. The data, classified according to relation with symmetric or asymmetric field types, strongly suggest that retina maturation is the key factor in the rate of development in central visual pathways, and that central synaptic connections are made before the onset of retinal activity.

  5. Frog striated muscle is permeable to hydroxide and buffer anions.

    PubMed

    Venosa, R A; Kotsias, B A; Horowicz, P

    1994-04-01

    Hydroxide, bicarbonate and buffer anion permeabilities in semitendinosus muscle fibers of Rana pipiens were measured. In all experiments, the fibers were initially equilibrated in isotonic, high K2SO4 solutions at pHo = 7.2 buffered with phosphate. Two different methods were used to estimate permeabilities: (i) membrane potential changes were recorded in response to changes in external ion concentrations, and (ii) intracellular pH changes were recorded in response to changes in external concentrations of ions that alter intracellular pH. Constant field equations were used to calculate relative or absolute permeabilities. In the first method, to increase the size of the membrane potential change produced by a sudden change in anion entry, external K+ was replaced by Cs+ prior to changes of the anion under study. At constant external Cs+ activity, a hyperpolarization results from increasing external pH from 7.2 to 10.0 or higher, using either CAPS (3-[cyclohexylamino]-1-propanesulfonic acid) or CHES (2-[N-cyclohexylamino]-ethanesulfonic acid) as buffer. For each buffer, the protonated form is a zwitterion of zero net charge and the nonprotonated form is an anion. Using reported values of H+ permeability, calculations show that the reduction in [H+]o cannot account for the hyperpolarizations produced by alkaline solutions. Membrane hyperpolarization increases with increasing total external buffer concentration at constant external pH, and with increasing external pH at constant external buffer anion concentration. Taken together, these observations indicate that both OH- and buffer anions permeate the surface membrane. The following relative permeabilities were obtained at pHo = 10.0 +/- 0.3: (POH/PK) = 890 +/- 150, (PCAPS/PK) = 12 +/- 2, (PCHES/PK) = 5.3 +/- 0.9, and (PNO3/PK) = 4.7 +/- 0.5. PNO3/PK was independent of pHo up to 10.75. At pHo = 9.6, (PHCO3/PK) = 0.49 +/- 0.03; at pHo = 8.9, (PCl/PK) = 18 +/- 2 and at pHo = 7.1, (PHEPES/PK) = 20 +/- 2. In the second method, on increasing external pH from 7.2 to 10.0, using 2.5 mM CAPS (total buffer concentration), the internal pH increases linearly with time over the next 10 min. This alkalinization is due to the entry of OH- and the absorption of internal H+ by entering CAPS- anion. The rate of CAPS- entry was determined in experiments in which the external CAPS concentration was increased at constant external pH. Such increases invariably produced an increase in the rate of internal alkalinization, which was reversed when the CAPS concentration was reduced to its initial value.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:8071988

  6. Critical current density measurement of striated multifilament-coated conductors using a scanning Hall probe microscope

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Fen; Kochat, Mehdi; Majkic, Goran; Selvamanickam, Venkat

    2016-08-01

    In this paper the authors succeeded in measuring the critical current density ({J}{{c}}) of multifilament-coated conductors (CCs) with thin filaments as low as 0.25 mm using the scanning hall probe microscope (SHPM) technique. A new iterative method of data analysis is developed to make the calculation of {J}{{c}} for thin filaments possible, even without a very small scan distance. The authors also discussed in detail the advantage and limitation of the iterative method using both simulation and experiment results. The results of the new method correspond well with the traditional fast Fourier transform method where this is still applicable. However, the new method is applicable for the filamentized CCs in much wider measurement conditions such as with thin filament and a large scan distance, thus overcoming the barrier for application of the SHPM technique on {J}{{c}} measurement of long filamentized CCs with narrow filaments.

  7. A region of the myosin rod important for interaction with paramyosin in Caenorhabditis elegans striated muscle.

    PubMed Central

    Hoppe, P E; Waterston, R H

    2000-01-01

    The precise arrangement of molecules within the thick filament, as well as the mechanisms by which this arrangement is specified, remains unclear. In this article, we have exploited a unique genetic interaction between one isoform of myosin heavy chain (MHC) and paramyosin in Caenorhabditis elegans to probe the molecular interaction between MHC and paramyosin in vivo. Using chimeric myosin constructs, we have defined a 322-residue region of the MHC A rod critical for suppression of the structural and motility defects associated with the unc-15(e73) allele. Chimeric constructs lacking this region of MHC A either fail to suppress, or act as dominant enhancers of, the e73 phenotype. Although the 322-residue region is required for suppression activity, our data suggest that sequences along the length of the rod also play a role in the isoform-specific interaction between MHC A and paramyosin. Our genetic and cell biological analyses of construct behavior suggest that the 322-residue region of MHC A is important for thick filament stability. We present a model in which this region mediates an avid interaction between MHC A and paramyosin in parallel arrangement in formation of the filament arms. PMID:11014812

  8. The formation and regression of synapses during the re-innervation of axolotl striated muscles.

    PubMed Central

    Bennett, M R; Raftos, J

    1977-01-01

    1. A study has been made of the formation and regression of synapses formed by spinal nerves 16 and 17 in axolotl hind-limb flexor muscles following the severing of nerve 16, using histological, ultrastructural and electrophysiological techniques. 2. Axolotl hind-limb flexor myofibres possessed 'en plaque' end-plates from either spinal nerve 16 or 17 or both at intervals of about 1000 micronm along their length; the myofibre's length constant was about 700 micronm allowing electrophysiological observations of at least two of these synapses during a single impalement; transmitter release at these synapses could be described by binomial statistics and in a given set of ionic conditions the binomial statistic parameter n was directly proportional to the size of the nerve terminals whilst the binomial statistic parameter p was invariant to changes in nerve terminal size. 3. The distribution of synapses formed by spinal nerves 16 and 17 in different sectors of the axolotl hind-limb flexor muscles was determined from a study of evoked end-plate potentials; the middle and proximal sectors of the flexor muscles contained myofibres which received an innervation from nerve 16 only, whereas the sectors surrounding these contained myofibres innervated either by nerve 16 or nerve 17 or by both nerves. 4. Six days following the severing of spinal nerve 16, evoked transmitter release from the synapses formed by this nerve had failed; transmission was subsequently recorded at a few synapses formed by nerve 17 in the middle and proximal sectors of the flexor muscles which are not normally innervated by this nerve and these synapses had a low n; during the succeeding four weeks the value of n at the synapses increased to a size about 70% that of the terminals normally formed by nerve 16 at these sites. 5. Four weeks after severing nerve 16, myofibres which possessed synapses formed by nerve 17 also possessed synapses from re-innervating nerve 16 and these were sometimes formed at the same synaptic sites as those occupied by nerve 17. 6. In the subsequent sixteen weeks, the n value of synapses formed by nerve 17 declined whilst the n values of synapses formed by re-innervating nerve 16 on the same myofibres matured to their control size. 7. It is suggested that on severing nerve 16 collateral sprouting of nearby intact nerve 17 occurs and these collateral sprouts innervate the denervated synaptic sites, although the sprouts arenot as well matched to the denervated synaptic sites as are the original nerve terminals; thus if nerve 16 returns it preferentially forms synapses at its original synaptic sites, and the collateral synapses formed by nerve 17 regress. Images Plate 1 Plate 2 PMID:191597

  9. Triclosan impairs excitation-contraction coupling and Ca2+ dynamics in striated muscle.

    PubMed

    Cherednichenko, Gennady; Zhang, Rui; Bannister, Roger A; Timofeyev, Valeriy; Li, Ning; Fritsch, Erika B; Feng, Wei; Barrientos, Genaro C; Schebb, Nils H; Hammock, Bruce D; Beam, Kurt G; Chiamvimonvat, Nipavan; Pessah, Isaac N

    2012-08-28

    Triclosan (TCS), a high-production-volume chemical used as a bactericide in personal care products, is a priority pollutant of growing concern to human and environmental health. TCS is capable of altering the activity of type 1 ryanodine receptor (RyR1), but its potential to influence physiological excitation-contraction coupling (ECC) and muscle function has not been investigated. Here, we report that TCS impairs ECC of both cardiac and skeletal muscle in vitro and in vivo. TCS acutely depresses hemodynamics and grip strength in mice at doses ≥12.5 mg/kg i.p., and a concentration ≥0.52 μM in water compromises swimming performance in larval fathead minnow. In isolated ventricular cardiomyocytes, skeletal myotubes, and adult flexor digitorum brevis fibers TCS depresses electrically evoked ECC within ∼10-20 min. In myotubes, nanomolar to low micromolar TCS initially potentiates electrically evoked Ca(2+) transients followed by complete failure of ECC, independent of Ca(2+) store depletion or block of RyR1 channels. TCS also completely blocks excitation-coupled Ca(2+) entry. Voltage clamp experiments showed that TCS partially inhibits L-type Ca(2+) currents of cardiac and skeletal muscle, and [(3)H]PN200 binding to skeletal membranes is noncompetitively inhibited by TCS in the same concentration range that enhances [(3)H]ryanodine binding. TCS potently impairs orthograde and retrograde signaling between L-type Ca(2+) and RyR channels in skeletal muscle, and L-type Ca(2+) entry in cardiac muscle, revealing a mechanism by which TCS weakens cardiac and skeletal muscle contractility in a manner that may negatively impact muscle health, especially in susceptible populations. PMID:22891308

  10. Neural Representations of Natural and Scrambled Movies Progressively Change from Rat Striate to Temporal Cortex.

    PubMed

    Vinken, Kasper; Van den Bergh, Gert; Vermaercke, Ben; Op de Beeck, Hans P

    2016-07-01

    In recent years, the rodent has come forward as a candidate model for investigating higher level visual abilities such as object vision. This view has been backed up substantially by evidence from behavioral studies that show rats can be trained to express visual object recognition and categorization capabilities. However, almost no studies have investigated the functional properties of rodent extrastriate visual cortex using stimuli that target object vision, leaving a gap compared with the primate literature. Therefore, we recorded single-neuron responses along a proposed ventral pathway in rat visual cortex to investigate hallmarks of primate neural object representations such as preference for intact versus scrambled stimuli and category-selectivity. We presented natural movies containing a rat or no rat as well as their phase-scrambled versions. Population analyses showed increased dissociation in representations of natural versus scrambled stimuli along the targeted stream, but without a clear preference for natural stimuli. Along the measured cortical hierarchy the neural response seemed to be driven increasingly by features that are not V1-like and destroyed by phase-scrambling. However, there was no evidence for category selectivity for the rat versus nonrat distinction. Together, these findings provide insights about differences and commonalities between rodent and primate visual cortex. PMID:27146315

  11. Visual field defects after missile injuries to the geniculo-striate pathway in man.

    NASA Technical Reports Server (NTRS)

    Koerner, F.; Teuber, H.-L.

    1973-01-01

    The main objective of the survey reported was a quantitative comparison of different visual functions at identical retinal points of individual patients. The possibility to develop objective forms of visual-field testing was also explored, taking into account reports by Frydrychowicz and Harms (1940) and Harms (1951). These investigators had insisted that pupillary responses to light are depressed in areas of homonymous scotomata. The shapes of homonymous visual field defects are discussed together with questions regarding the association and dissociation of symptoms.

  12. The toxic effect of R350P mutant desmin in striated muscle of man and mouse.

    PubMed

    Clemen, Christoph S; Stöckigt, Florian; Strucksberg, Karl-Heinz; Chevessier, Frederic; Winter, Lilli; Schütz, Johanna; Bauer, Ralf; Thorweihe, José-Manuel; Wenzel, Daniela; Schlötzer-Schrehardt, Ursula; Rasche, Volker; Krsmanovic, Pavle; Katus, Hugo A; Rottbauer, Wolfgang; Just, Steffen; Müller, Oliver J; Friedrich, Oliver; Meyer, Rainer; Herrmann, Harald; Schrickel, Jan Wilko; Schröder, Rolf

    2015-02-01

    Mutations of the human desmin gene on chromosome 2q35 cause autosomal dominant, autosomal recessive and sporadic forms of protein aggregation myopathies and cardiomyopathies. We generated R349P desmin knock-in mice, which harbor the ortholog of the most frequently occurring human desmin missense mutation R350P. These mice develop age-dependent desmin-positive protein aggregation pathology, skeletal muscle weakness, dilated cardiomyopathy, as well as cardiac arrhythmias and conduction defects. For the first time, we report the expression level and subcellular distribution of mutant versus wild-type desmin in our mouse model as well as in skeletal muscle specimens derived from human R350P desminopathies. Furthermore, we demonstrate that the missense-mutant desmin inflicts changes of the subcellular localization and turnover of desmin itself and of direct desmin-binding partners. Our findings unveil a novel principle of pathogenesis, in which not the presence of protein aggregates, but disruption of the extrasarcomeric intermediate filament network leads to increased mechanical vulnerability of muscle fibers. These structural defects elicited at the myofiber level finally impact the entire organ and subsequently cause myopathy and cardiomyopathy. PMID:25394388

  13. In vitro and in vivo single myosin step-sizes in striated muscle.

    PubMed

    Burghardt, Thomas P; Sun, Xiaojing; Wang, Yihua; Ajtai, Katalin

    2015-12-01

    Myosin in muscle transduces ATP free energy into the mechanical work of moving actin. It has a motor domain transducer containing ATP and actin binding sites, and, mechanical elements coupling motor impulse to the myosin filament backbone providing transduction/mechanical-coupling. The mechanical coupler is a lever-arm stabilized by bound essential and regulatory light chains. The lever-arm rotates cyclically to impel bound filamentous actin. Linear actin displacement due to lever-arm rotation is the myosin step-size. A high-throughput quantum dot labeled actin in vitro motility assay (Qdot assay) measures motor step-size in the context of an ensemble of actomyosin interactions. The ensemble context imposes a constant velocity constraint for myosins interacting with one actin filament. In a cardiac myosin producing multiple step-sizes, a "second characterization" is step-frequency that adjusts longer step-size to lower frequency maintaining a linear actin velocity identical to that from a shorter step-size and higher frequency actomyosin cycle. The step-frequency characteristic involves and integrates myosin enzyme kinetics, mechanical strain, and other ensemble affected characteristics. The high-throughput Qdot assay suits a new paradigm calling for wide surveillance of the vast number of disease or aging relevant myosin isoforms that contrasts with the alternative model calling for exhaustive research on a tiny subset myosin forms. The zebrafish embryo assay (Z assay) performs single myosin step-size and step-frequency assaying in vivo combining single myosin mechanical and whole muscle physiological characterizations in one model organism. The Qdot and Z assays cover "bottom-up" and "top-down" assaying of myosin characteristics. PMID:26728749

  14. The morphology and cell culture of the striated musculature of the rat azygos vein.

    PubMed

    Cullinan, V; Campbell, J H; Mosse, P R; Campbell, G R

    1986-01-01

    The azygos vein of the rat can be divided into three regions: The proximal cardiac region, where the wall is composed of two and sometimes three layers of cardiac muscle and a thin discontinuous layer of smooth muscle cells. Vascular casts of this region demonstrate layers of capillaries closely following the orientation of the cardiac fibres. A transitional zone, where both cardiac and smooth muscle cells interdigitate. In this zone, close associations between smooth muscle and cardiac muscle cells can be observed, however, gap junctions do not appear to be present. Beyond this transitional zone the vessel resembles a typical thin-walled vein. The cells of the media of the entire length of azygous vein have been isolated and grown in culture and two separate viable populations identified corresponding to smooth and cardiac muscle. PMID:3510740

  15. Androgens enhance in vivo 2-deoxyglucose uptake by rat striated muscle

    NASA Technical Reports Server (NTRS)

    Max, S. R.; Toop, J.

    1983-01-01

    It is shown that testosterone propionate (TP) causes a striking increase in the in vivo uptake of 2-deoxyglucose (2-DG) by the levator ani muscle of immature male rats, which was found to be uniformly distributed over the entire muscle. After a single subcutaneous injection of TP, no enhancement of 2-DG was observed before 3.5 hr, at which time uptake was increased 2-fold; maximum enhancement (4-fold) was attained at 12 hr. At 72 hr, 2-DG uptake remained elevated at twice the control value. It was determined that the effect of TP probably is mediated by specific androgen receptors. In addition, it was found that the effect of TP was blocked by the simultaneous administration of an androgen antagonist, cyproterone acetate. TP also was found to enhance the uptake of 2-DG in the bulbocavernosus (253 percent over control) and extensor digitorum longus muscles (150 percent over control), but not in the biceps brachii or soleus. It is suggested that the increased uptake of glucose may be an important early step in the anabolic response of muscle to androgens.

  16. Topographic reorganization in the striate cortex of the adult cat and monkey is cortically mediated.

    PubMed

    Darian-Smith, C; Gilbert, C D

    1995-03-01

    In primary sensory and motor cortex of adult animals, alteration of input from the periphery leads to changes in cortical topography. These changes can be attributed to processes that are intrinsic to the cortex, or can be inherited from alterations occurring at stages of sensory processing that are antecedent to the primary sensory cortical areas. In the visual system, focal binocular retinal lesions initially silence an area of cortex that represents the region of retina destroyed, but over a period of months this area recovers visually driven activity. The retinotopic map in the recovered area is altered, shifting its representation to the portion of retina immediately surrounding the lesion. This effectively shrinks the representation of the lesioned area of retina, and expands the representation of the lesion surround. To determine the loci along the visual pathway at which the reorganization takes place, we compared the course of topographic alterations in the primary visual cortex and dorsal lateral geniculate nucleus (LGN) of cats and monkeys. At a time when the cortical reorganization is complete, the silent area of LGN persists, indicating that changes in cortical topography are due to alterations that are intrinsic to the cortex. To explore the participation of thalamocortical afferents in the reorganization, we injected a series of retrogradely transported fluorescent tracers into reorganized and surrounding cortex of each animal. Our results show that the thalamocortical arbors do not extend beyond their normal lateral territory and that this physical dimension is insufficient to account for the reorganization. We suggest that the long-range intrinsic horizontal connections are a likely source of visual input into the reorganized cortical area. PMID:7891124

  17. Neural Representations of Natural and Scrambled Movies Progressively Change from Rat Striate to Temporal Cortex

    PubMed Central

    Vinken, Kasper; Van den Bergh, Gert; Vermaercke, Ben; Op de Beeck, Hans P.

    2016-01-01

    In recent years, the rodent has come forward as a candidate model for investigating higher level visual abilities such as object vision. This view has been backed up substantially by evidence from behavioral studies that show rats can be trained to express visual object recognition and categorization capabilities. However, almost no studies have investigated the functional properties of rodent extrastriate visual cortex using stimuli that target object vision, leaving a gap compared with the primate literature. Therefore, we recorded single-neuron responses along a proposed ventral pathway in rat visual cortex to investigate hallmarks of primate neural object representations such as preference for intact versus scrambled stimuli and category-selectivity. We presented natural movies containing a rat or no rat as well as their phase-scrambled versions. Population analyses showed increased dissociation in representations of natural versus scrambled stimuli along the targeted stream, but without a clear preference for natural stimuli. Along the measured cortical hierarchy the neural response seemed to be driven increasingly by features that are not V1-like and destroyed by phase-scrambling. However, there was no evidence for category selectivity for the rat versus nonrat distinction. Together, these findings provide insights about differences and commonalities between rodent and primate visual cortex. PMID:27146315

  18. Testosterone enhances C-14 2-deoxyglucose uptake by striated muscle. [sex hormones and muscle

    NASA Technical Reports Server (NTRS)

    Toop, J.; Max, S. R.

    1982-01-01

    The effect of testosterone propionate (TP) on C-14 2-deoxyglucose (C-14 2DG) uptake was studied in the rat levator ani muscle in vivo using the autoradiographic technique. Following a delay of 1 to 3 h after injecting TP, the rate of C-14 2DG uptake in experimental animals began to increase and continued to increase for at least 20 h. The label, which corresponds to C-14 2-deoxyglucose 6-phosphate, as demonstrated by chromatographic analysis of muscle extracts, was uniformly distributed over the entire muscle and was predominantly in muscle fibers, although nonmuscular elements were also labeled. The 1 to 3 h time lag suggests that the TP effect may be genomic, acting via androgen receptors, rather than directly on muscle membranes. Acceleration of glucose uptake may be an important early event in the anabolic response of the rat levator ani muscle to androgens.

  19. Modulation of the cytosolic androgen receptor in striated muscle by sex steroids

    NASA Technical Reports Server (NTRS)

    Rance, N. E.; Max, S. R.

    1984-01-01

    The effects of orchiectomy (GDX) and of subsequent administration of testosterone propionate (TP) or 17(beta)-estradiol (E2) on the maximum binding (Bmax) and apparent Kd of the cytosolic androgen receptor in levator ani (LA) and skeletal muscles of adult male Sprague-Dawley rats are investigated experimentally. The results are presented in graphs and discussed. In LA, BMAX is found to rise from a control level of 2.5 fmol/mg protein to 280, 600, 478, and 133 percent of control at 12 h, 14 d, 30 d, and 44 d after GDX, respectively, while Kd increased only insignificantly (from 680 to 960 fM); Bmax is held at control levels for 6 h by cycloheximide given at GDX, is unaffected by TP given at 30 d, and is further increased (by 480 percent at 44 d) by administration of E2 at 30 d. Bmax in skeletal muscles is found to increase to 139, 212, 220, and 158 percent of control at 12 h, 14 d, 30 d, and 44 d, respectively; Bmax is returned to control at 44 d by TP at 30 d but is not affected by E2. The effect of E2 in LA is attributed to either induction of the cytosolic receptor or a decreased rate of receptor degradation.

  20. Thermal dependence of force-velocity relation of lamprey live striated muscle fibres.

    PubMed

    Sobol, C V; Nasledov, G A

    1994-06-01

    The thermal dependence of the force-velocity relation (P - V) in thin (20-40 fibres) live twitch muscle bundles from suction apparatus of lamprey by force-clamp method was investigated. The P - V relation was hyperbolic and Hill's constants were as follows: a/P0 was 0.13 +/- 0.01 and 0.08 +/- 0.01 (mean +/- S.E.M.), b was 0.46 +/- 0.02 and 0.65 +/- 0.03 at 8 degrees C and 18 degrees C, respectively. The maximal isometric tension (P0) was about 100 mN/mm2 at 8 degrees C, 18 degrees C, and 22 degrees C. After the temperature was switched from 8 degrees C to 18 degrees C, the dependence of P0 on incubation time was observed. The maximal power output determined from P - V relation using Hill's equation was 0.062 +/- 0.002 and 0.056 +/- 0.001 at 8 degrees C and 18 degrees C, respectively. The maximal velocities of shortening (V0) were 3.9 +/- 0.1 L0/s and 7.2 +/- 0.2 L0/s at 8 degrees C and 18 degrees C, respectively. Q10 for V0 in this range of temperatures was 1.86. a/P0 and power output were about 2 times lower than those reported in literature for other animals. In general, the thermal dependence of the parameters studied was similar to those reported for fish muscles and skinned lamprey muscles, P0 being relatively independent, V0 highly dependent, and a/P0 inversely dependent on temperature. PMID:7835682

  1. Spatial summation in the receptive fields of simple cells in the cat's striate cortex.

    PubMed Central

    Movshon, J A; Thompson, I D; Tolhurst, D J

    1978-01-01

    1. We have examined the responses of simple cells in the cat's atriate cortex to visual patterns that were designed to reveal the extent to which these cells may be considered to sum light-evoked influences linearly across their receptive fields. We used one-dimensional luminance-modulated bars and grating as stimuli; their orientation was always the same as the preferred orientation of the neurone under study. The stimuli were presented on an oscilloscope screen by a digital computer, which also accumulated neuronal responses and controlled a randomized sequence of stimulus presentations. 2. The majority of simple cells respond to sinusoidal gratings that are moving or whose contrast is modulated in time in a manner consistent with the hypothesis that they have linear spatial summation. Their responses to moving gratings of all spatial frequencies are modulated in synchrony with the passage of the gratings' bars across their receptive fields, and they do not produce unmodulated responses even at the highest spatial frequencies. Many of these cells respond to temporally modulated stationary gratings simply by changing their response amplitude sinusoidally as the spatial phase of the grating the grating is varied. Nonetheless, their behavior appears to indicate linear spatial summation, since we show in an Appendix that the absence of a 'null' phase in a visual neurone need not indicate non-linear spatial summation, and further that a linear neurone lacking a 'null' phase should give responses of the form that we have observed in this type of simple cell. 3. A minority of simple cells appears to have significant non-linearities of spatial summation. These neurones respond to moving gratings of high spatial frequency with a partially or totally unmodulated elevation of firing rate. They have no 'null' phases when tested with stationary gratings, and reveal their non-linearity by giving responses to gratings of some spatial phases that are composed partly or wholly of even harmonics of the stimulus frequency ('on-off' responses). 4. We compared simple receptive fields with their sensitivity to sinusoidal gratings of different spatial frequencies. Qualitatively, the most sensitive subregions of simple cells' receptive fields are roughly the same width as the individual bars of the gratings to which they are most sensitive. Quantitatively, their receptive field profiles measured with thin stationary lines, agree well with predicted profiles derived by Fourier synthesis of their spatial frequency tuning curves. PMID:722589

  2. Fluid model of a single striated filament in an RF plasma jet at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Sigeneger, F.; Loffhagen, D.

    2016-06-01

    The filaments occurring in an RF argon atmospheric-pressure plasma jet are investigated by means of numerical modelling. The special setup of the jet leads to the establishment of filaments in very regular modes under certain conditions. Such a single filament generated in the active volume between the powered and grounded electrode is described by a time-dependent, spatially two-dimensional fluid model. This self-consistent model includes those mechanisms which can lead to constriction and stratification such as the heat balance equation and the dependence of electron collision rate coefficients on the ionization degree. A curved filament with a contracted radial profile of particle densities and very pronounced striations along its trace has been obtained by the model calculation for a typical discharge parameter condition of the plasma jet. The resulting calculated electron density and mean energy in the filament as well as the period length of the striations agree qualitatively with recent experimental observations. The analysis of the ionization budget makes clear that the constriction and stratification is mainly caused by the different nonlinear dependences of ionization and recombination rates on the electron density.

  3. Electron microscopical and histochemical studies on the transverse striated muscles of birds after prolonged hypokinesis

    NASA Technical Reports Server (NTRS)

    Belak, M.; Kocisova, J.; Marcanik, J.; Boda, K.; Skarda, R.

    1981-01-01

    Studies of the gastrocnemius muscle were carried out in 4 month old cockerels of the laying hybrid after hypokinesis lasting 15 and 30 days. It was found that restricted movement resulted in dystrophic changes of myotibrils, enlargement of the sarcoplasmic reticulum and oedem of interfibrillar spaces. Histochemical studies revealed focuses of increased activity of non-specific esterase, decreased activity of dehydrogenase of lactic acid and a positive reaction of acid phosphatase.

  4. [Ultrastructural changes in transverse striated muscles under the influence of space flight factors].

    PubMed

    Pozdniakov, O M; Babakova, L L; Demorzhi, M S

    1988-12-01

    The influence of space flight (on the biosatellite "Kosmos-1667") on muscles (diaphragmatic, soleus, gastrocnemius) was studied by electron microscope. Muscles had destructive and atrophic changes. The rate of changes was maximal in m. soleus, minimal in the diaphragmatic m. However, some regeneration was found demonstrating the reversibility of changes. PMID:2974735

  5. Holonomy, quantum mechanics and the signal-tuned Gabor approach to the striate cortex

    NASA Astrophysics Data System (ADS)

    Torreão, José R. A.

    2016-02-01

    It has been suggested that an appeal to holographic and quantum properties will be ultimately required for the understanding of higher brain functions. On the other hand, successful quantum-like approaches to cognitive and behavioral processes bear witness to the usefulness of quantum prescriptions as applied to the analysis of complex non-quantum systems. Here, we show that the signal-tuned Gabor approach for modeling cortical neurons, although not based on quantum assumptions, also admits a quantum-like interpretation. Recently, the equation of motion for the signal-tuned complex cell response has been derived and proven equivalent to the Schrödinger equation for a dissipative quantum system whose solutions come under two guises: as plane-wave and Airy-packet responses. By interpreting the squared magnitude of the plane-wave solution as a probability density, in accordance with the quantum mechanics prescription, we arrive at a Poisson spiking probability — a common model of neuronal response — while spike propagation can be described by the Airy-packet solution. The signal-tuned approach is also proven consistent with holonomic brain theories, as it is based on Gabor functions which provide a holographic representation of the cell’s input, in the sense that any restricted subset of these functions still allows stimulus reconstruction.

  6. Effects of different activity and inactivity paradigms on myosin heavy chain gene expression in striated muscle

    NASA Technical Reports Server (NTRS)

    Baldwin, K. M.; Haddad, F.

    2001-01-01

    The goal of this mini-review is to summarize findings concerning the role that different models of muscular activity and inactivity play in altering gene expression of the myosin heavy chain (MHC) family of motor proteins in mammalian cardiac and skeletal muscle. This was done in the context of examining parallel findings concerning the role that thyroid hormone (T(3), 3,5,3'-triiodothyronine) plays in MHC expression. Findings show that both cardiac and skeletal muscles of experimental animals are initially undifferentiated at birth and then undergo a marked level of growth and differentiation in attaining the adult MHC phenotype in a T(3)/activity level-dependent fashion. Cardiac MHC expression in small mammals is highly sensitive to thyroid deficiency, diabetes, energy deprivation, and hypertension; each of these interventions induces upregulation of the beta-MHC isoform, which functions to economize circulatory function in the face of altered energy demand. In skeletal muscle, hyperthyroidism, as well as interventions that unload or reduce the weight-bearing activity of the muscle, causes slow to fast MHC conversions. Fast to slow conversions, however, are seen under hypothyroidism or when the muscles either become chronically overloaded or subjected to intermittent loading as occurs during resistance training and endurance exercise. The regulation of MHC gene expression by T(3) or mechanical stimuli appears to be strongly regulated by transcriptional events, based on recent findings on transgenic models and animals transfected with promoter-reporter constructs. However, the mechanisms by which T(3) and mechanical stimuli exert their control on transcriptional processes appear to be different. Additional findings show that individual skeletal muscle fibers have the genetic machinery to express simultaneously all of the adult MHCs, e.g., slow type I and fast IIa, IIx, and IIb, in unique combinations under certain experimental conditions. This degree of heterogeneity among the individual fibers would ensure a large functional diversity in performing complex movement patterns. Future studies must now focus on 1) the signaling pathways and the underlying mechanisms governing the transcriptional/translational machinery that control this marked degree of plasticity and 2) the morphological organization and functional implications of the muscle fiber's capacity to express such a diversity of motor proteins.

  7. Cortical connections of striate and extrastriate visual areas in tree shrews.

    PubMed

    Lyon, D C; Jain, N; Kaas, J H

    1998-11-01

    The ipsilateral and contralateral cortical connections of visual cortex of tree shrews (Tupaia belangeri) were investigated by placing restricted injections of fluorochrome tracers, wheat germ agglutinin-horseradish peroxidase, or biotinylated dextran amine into area 17 (V1), area 18 (V2), or the adjoining temporal dorsal area (TD). As previously reported, V1 was characterized by a widespread, patchy pattern of intrinsic connections; ipsilateral connections with V2, TD, and to a lesser extent, other areas of the temporal cortex; and contralateral connections with V1, V2, and TD. A surface-view of the myelin pattern in V1 revealed a patchwork of light and dark module-like regions. The ipsilateral connections with V2 and TD were roughly topographic, whereas heterotopic locations in V1 were callosally connected. Injections in V2 labeled as much as one third of V2 in a patchy pattern, and portions of ipsilateral V1 and TD in roughly topographic patterns. In addition, connections with several other visual areas in the temporal lobe were revealed. Contralaterally, most of the label was in V2, with some in V1 and TD. Injections in TD demonstrated connections within the region, and with adjoining portions of the temporal cortex, V2, and V1. There were sparse connections with an oval of densely myelinated cortex, which we have termed the temporal inferior area (TI). Callosal connections were concentrated in TD, but also included V2. The results provide further evidence for modular organizations within V1 and V2, and reveal for the first time the complete patterns of cortical connections of V2 and TD. The results are consistent with the proposal that at least three visual areas, the temporal anterior area, TA, the temporal dorsal area, TD, and the temporal posterior area, TP, exist along the rostrolateral border of V2 in tree shrews; suggest visual involvement of at least three other areas, the temporal inferior area, TI, the temporal anterior lateral area, and the temporal posterior inferior area located more ventrally in the temporal cortex; and fortify the conclusion that TD is the likely homologue of the middle temporal visual area of primates. Because tree shrews are considered close relatives of primates, the evidence for several visual areas along the border of V2 is more compatible with theories that propose a series of visual areas along V2 in primates, rather than a single visual area, V3. PMID:9802703

  8. The increase in non-cross-bridge forces after stretch of activated striated muscle is related to titin isoforms.

    PubMed

    Cornachione, Anabelle S; Leite, Felipe; Bagni, Maria Angela; Rassier, Dilson E

    2016-01-01

    Skeletal muscles present a non-cross-bridge increase in sarcomere stiffness and tension on Ca(2+) activation, referred to as static stiffness and static tension, respectively. It has been hypothesized that this increase in tension is caused by Ca(2+)-dependent changes in the properties of titin molecules. To verify this hypothesis, we investigated the static tension in muscles containing different titin isoforms. Permeabilized myofibrils were isolated from the psoas, soleus, and heart ventricle from the rabbit, and tested in pCa 9.0 and pCa 4.5, before and after extraction of troponin C, thin filaments, and treatment with the actomyosin inhibitor blebbistatin. The myofibrils were tested with stretches of different amplitudes in sarcomere lengths varying between 1.93 and 3.37 μm for the psoas, 2.68 and 4.21 μm for the soleus, and 1.51 and 2.86 μm for the ventricle. Using gel electrophoresis, we confirmed that the three muscles tested have different titin isoforms. The static tension was present in psoas and soleus myofibrils, but not in ventricle myofibrils, and higher in psoas myofibrils than in soleus myofibrils. These results suggest that the increase in the static tension is directly associated with Ca(2+)-dependent change in titin properties and not associated with changes in titin-actin interactions. PMID:26405100

  9. Two Biological Active Fractions Isolated from Buthotus schach (BS)Scorpion Venom Examined on Striated Muscle Preparation, In-vitro

    PubMed Central

    Vatanpour, Hossein; Ahmadi, Farhad; Zare Mirakabadi, Abbas; Jalali, Amir

    2012-01-01

    Buthotus schach is one of the most dangerous scorpions in tropical part of Iran. The effects of its crude venom at 1, 3, 10 μg/mL and its obtained fractions by gel filtrations were investigated on neuromuscular transmission. CBC and MHD indirectly and directly stimulated preparations techniques were used to study their possible pre or post junctional activities. At 3 and 10 μg/mL (not at 1 μg/mL), BS venom caused initiall increase in twitch height followed by blockage due to large contraction that responded gradually at the same time. Contracture responses to exogenous Ach (1-2 mM, 30 sec) and Carb (30-40 μM, 60 sec) in the presence of the venom were not increased which does show no anticholinstrease effects. Furthermore Contracture response to KCl (20-40 mM, 30 sec) does changed exposure to venom in CBC preparations. On the other hand the effects of the venom in response to directly stimulated preparations was shallower than in indirect stimulated preparations. So in agreement with KCL response BS venom affects mostly prejunctionally to facilitate the neurotransmitter release rather than postjunctionally effects. To access bioactive components, seven fractions were collected by gel filtrations techniques. Among the fractions F6, LD50=21 μg < F4, LD50= 35.5 μg < Venom LD50= 84 μg per mice were more toxic respectively. Both fractions show the same effects but stronger than venom on twitch height responses in indirectly stimulated CBC preparations. Finally, according to our results venom as well as fractions F4 and F6 act mostly prejunctionally on Ach release. More attempt is carrying out to study their effects on ion channel activities. PMID:24250518

  10. Visual responses of neurones in the second visual area of flying foxes (Pteropus poliocephalus) after lesions of striate cortex

    PubMed Central

    Funk, Agnes P; Rosa, Marcello G P

    1998-01-01

    The first (V1) and second (V2) cortical visual areas exist in all mammals. However, the functional relationship between these areas varies between species. While in monkeys the responses of V2 cells depend on inputs from V1, in all non-primates studied so far V2 cells largely retain responsiveness to photic stimuli after destruction of V1.We studied the visual responsiveness of neurones in V2 of flying foxes after total or partial lesions of the primary visual cortex (V1). The main finding was that visual responses can be evoked in the region of V2 corresponding, in visuotopic co-ordinates, to the lesioned portion of V1 (‘lesion projection zone’; LPZ).The visuotopic organization of V2 was not altered by V1 lesions.The proportion of neurones with strong visual responses was significantly lower within the LPZs (31.5 %) than outside these zones, or in non-lesioned control hemispheres (> 70 %). LPZ cells showed weak direction and orientation bias, and responded consistently only at low spatial and temporal frequencies.The data demonstrate that the functional relationship between V1 and V2 of flying foxes resembles that observed in non-primate mammals. This observation contrasts with the ‘primate-like’ characteristics of the flying fox visual system reported by previous studies. PMID:9806999

  11. Promiscuous Actions of Small Molecule Inhibitors of the Protein Kinase D-Class IIa HDAC Axis in Striated Muscle

    PubMed Central

    Lemon, Douglas D.; Harrison, Brooke C.; Horn, Todd R.; Stratton, Matthew S.; Ferguson, Bradley S.; Wempe, Michael F.; McKinsey, Timothy A.

    2015-01-01

    PKD-mediated phosphorylation of class IIa HDACs frees the MEF2 transcription factor to activate genes that govern muscle differentiation and growth. Studies of the regulation and function of this signaling axis have involved MC1568 and Gö-6976, which are small molecule inhibitors of class IIa HDAC and PKD catalytic activity, respectively. We describe unanticipated effects of these compounds. MC1568 failed to inhibit class IIa HDAC catalytic activity in vitro, and exerted divergent effects on skeletal muscle differentiation compared to a bona fide inhibitor of these HDACs. In cardiomyocytes, Gö-6976 triggered calcium signaling and activated stress-inducible kinases. Based on these findings, caution is warranted when employing MC1568 and Gö-6976 as pharmacological tool compounds to assess functions of class IIa HDACs and PKD. PMID:25816750

  12. Myocyte nuclear factor, a novel winged-helix transcription factor under both developmental and neural regulation in striated myocytes.

    PubMed Central

    Bassel-Duby, R; Hernandez, M D; Yang, Q; Rochelle, J M; Seldin, M F; Williams, R S

    1994-01-01

    A sequence motif (CCAC box) within an upstream enhancer region of the human myoglobin gene is essential for transcriptional activity in both cardiac and skeletal muscle. A cDNA clone, myocyte nuclear factor (MNF), was isolated from a murine expression library on the basis of sequence-specific binding to the myoglobin CCAC box motif and was found to encode a novel member of the winged-helix or HNF-3/fork head family of transcription factors. Probes based on this sequence identify two mRNA species that are upregulated during myocyte differentiation, and antibodies raised against recombinant MNF identify proteins of approximately 90, 68, and 65 kDa whose expression is regulated following differentiation of myogenic cells in culture. In addition, the 90-kDa form of MNF is phosphorylated and is upregulated in intact muscles subjected to chronic motor nerve stimulation, a potent stimulus to myoglobin gene regulation. Amino acid residues 280 to 389 of MNF demonstrate 35 to 89% sequence identity to the winged-helix domain from other known members of this family, but MNF is otherwise divergent. A proline-rich amino-terminal region (residues 1 to 206) of MNF functions as a transcriptional activation domain. These studies provide the first evidence that members of the winged-helix family of transcription factors have a role in myogenic differentiation and in remodeling processes of adult muscles that occur in response to physiological stimuli. Images PMID:8007964

  13. Force generation and shift of mass between myosin and actin in skinned striated muscle fibres at low calcium concentrations.

    PubMed

    Schiereck, P; van Heijst, B G; Jansen, P M; Schiereck, J; van der Leun, M; Bras, W; de Beer, E L

    1998-01-01

    Skinned muscle fibres from the gracilis muscle of the rabbit were used to record small angle X-ray diffraction spectra under various contractile conditions. The intracellular calcium concentration, expressed as pCa, was varied between 8.0 and 5.74. Equatorial diffraction spectra were fitted by a function consisting of five Gaussian curves and a hyperbola to separate the (1.0), (1.1), (2.0), (2.1) and Z-line diffraction peaks. The hyperbola was used to correct for residual scattering in the preparation. The ratio between the intensities of the (1.1) and (1.0) peaks was defined as the relative transfer of mass between myosin and actin, due to crossbridge formation after activation by calcium. The relation between the ratio and the relative force of the fibre (normalized to the force at pCa 5.74 and sarcomere length 2.0 microns) was linear. At high pCa (from pCa 6.34 to 8.0) no active force was observed, while the ratio still decreased. Sarcomere length was recorded by laser diffraction. The laser diffraction patterns did not show changes in sarcomere length due to activation in the high pCa range (between 8.0 and 6.34). From these results the conclusion is drawn that crossbridge movement occurs even at subthreshold calcium concentrations in the cell, when no active force is exerted. Since no force is generated this movement may be related to crossbridges in the weakly bound state. PMID:9791940

  14. Some relations between changes in the linear electrical properties of striated muscle fibers and changes in ultrastructure.

    PubMed

    Freygang, W H; Rapoport, S I; Peachey, L D

    1967-11-01

    Some of the linear electrical properties of frog sartorius muscle have been investigated in Ringer's fluid and in a Ringer fluid made hypertonic by the addition of sucrose or NaCl. Electrical constants were determined from measurements of the phase angle of the admittance of a fiber for an applied alternating current, from measurements of the voltage induced by an inward pulse of current, and from measurements of the conduction velocity of the action potential and the time constant of its foot. The dilation of the transverse tubular system induced by the sucrose hypertonic Ringer fluid was correlated with the change in the electrical constants. From this it is concluded that a two time constant equivalent circuit for the membrane, as proposed by Falk and Fatt, is in good agreement with our results. Both the area of the membrane of the transverse tubular system, and the capacity (c(e)) attributed to it, increased in the sucrose hypertonic Ringer fluid. The resistance r(e), which is in series with c(e), did not fall when the transverse tubular system was dilated and probably is not located in that system. PMID:6063689

  15. Preserved striate cortex is not sufficient to support the McCollough effect: evidence from two patients with cerebral achromatopsia.

    PubMed

    Mullin, Caitlin R; Démonet, Jean François; Kentridge, Robert W; Heywood, Charles A; Goodale, Melvyn A; Steeves, Jennifer K E

    2009-01-01

    The McCollough effect (ME) is a colour aftereffect contingent on pattern orientation. This effect is generally thought to be mediated by primary visual cortex (V1) although this has remained the subject of some debate. To determine whether V1 is in fact sufficient to subserve the ME, we compared McCollough adaptation in controls to adaptation in two patients with damage to ventrotemporal cortex, resulting in achromatopsia, but who have spared V1. Each of these patients has some residual colour abilities of which he is unaware. Participants performed a 2AFC orientation-discrimination task for pairs of oblique and vertical/horizontal gratings both before and after adaptation to red/green oblique induction gratings. Successful ME induction would manifest itself as an improvement in oblique-orientation discrimination owing to the additional colour cue after adaptation. Indeed, in controls oblique grating discrimination improved post-adaptation. Further, a subdivision of our control group demonstrated successful ME induction despite a lack of conscious awareness of the added colour cue, indicating that conscious colour awareness is not required for ME induction. The patients, however, did not show improvement in oblique-orientation discrimination, indicating a lack of ME induction. This suggests that V1 must be connected to higher cortical colour areas to drive ME induction. PMID:20192125

  16. Multi-Tasking Role of the Mechanosensing Protein Ankrd2 in the Signaling Network of Striated Muscle

    PubMed Central

    Mittempergher, Lorenza; Campanaro, Stefano; Martinelli, Valentina C.; Mouly, Vincent; Valle, Giorgio; Kojic, Snezana; Faulkner, Georgine

    2011-01-01

    Background Ankrd2 (also known as Arpp) together with Ankrd1/CARP and DARP are members of the MARP mechanosensing proteins that form a complex with titin (N2A)/calpain 3 protease/myopalladin. In muscle, Ankrd2 is located in the I-band of the sarcomere and moves to the nucleus of adjacent myofibers on muscle injury. In myoblasts it is predominantly in the nucleus and on differentiation shifts from the nucleus to the cytoplasm. In agreement with its role as a sensor it interacts both with sarcomeric proteins and transcription factors. Methodology/Principal Findings Expression profiling of endogenous Ankrd2 silenced in human myotubes was undertaken to elucidate its role as an intermediary in cell signaling pathways. Silencing Ankrd2 expression altered the expression of genes involved in both intercellular communication (cytokine-cytokine receptor interaction, endocytosis, focal adhesion, tight junction, gap junction and regulation of the actin cytoskeleton) and intracellular communication (calcium, insulin, MAPK, p53, TGF-β and Wnt signaling). The significance of Ankrd2 in cell signaling was strengthened by the fact that we were able to show for the first time that Nkx2.5 and p53 are upstream effectors of the Ankrd2 gene and that Ankrd1/CARP, another MARP member, can modulate the transcriptional ability of MyoD on the Ankrd2 promoter. Another novel finding was the interaction between Ankrd2 and proteins with PDZ and SH3 domains, further supporting its role in signaling. It is noteworthy that we demonstrated that transcription factors PAX6, LHX2, NFIL3 and MECP2, were able to bind both the Ankrd2 protein and its promoter indicating the presence of a regulatory feedback loop mechanism. Conclusions/Significance In conclusion we demonstrate that Ankrd2 is a potent regulator in muscle cells affecting a multitude of pathways and processes. PMID:22016770

  17. Response of the JAK-STAT pathway to mammalian hibernation in 13-lined ground squirrel striated muscle.

    PubMed

    Logan, Samantha M; Tessier, Shannon N; Tye, Joann; Storey, Kenneth B

    2016-03-01

    Over the course of the torpor-arousal cycle, hibernators must make behavioral, physiological, and molecular rearrangements in order to keep a very low metabolic rate and retain organ viability. 13-lined ground squirrels (Ictidomys tridecemlineatus) remain immobile during hibernation, and although the mechanisms of skeletal muscle survival are largely unknown, studies have shown minimal muscle loss in hibernating organisms. Additionally, the ground squirrel heart undergoes cold-stress, reversible cardiac hypertrophy, and ischemia-reperfusion without experiencing fatal impairment. This study examines the role of the Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway in the regulation of cell stress in cardiac and skeletal muscles, comparing euthermic and hibernating ground squirrels. Immunoblots showed a fivefold decrease in JAK3 expression during torpor in skeletal muscle, along with increases in STAT3 and 5 phosphorylation and suppressors of cytokine signaling-1 (SOCS1) protein levels. Immunoblots also showed coordinated increases in STAT1, 3 and 5 phosphorylation and STAT1 inhibitor protein expression in cardiac muscle during torpor. PCR analysis revealed that the activation of these pro-survival signaling cascades did not result in coordinate changes in downstream genes such as anti-apoptotic B-cell lymphoma-2 (Bcl-2) family gene expression. Overall, these results indicate activation of the JAK-STAT pathway in both cardiac and skeletal muscles, suggesting a response to cellular stress during hibernation. PMID:26885984

  18. A Study of a Striated Positive Column after Ethanol Impurity Injection in an Air DC Glow Discharge

    NASA Astrophysics Data System (ADS)

    Berzak, Laura; Post Zwicker, Andrew

    2003-04-01

    In a glow discharge when ethanol (CH3CH2OH) was injected, a series of atypical striations formed through the positive column. When the pressure decreased as the ethanol evaporated and was evacuated by the vacuum pump, this behavior decayed away until only an anode glow or normal discharge remained. Varying interelectrode spacings and quantities of ethanol yielded similar patterns. The typical evolution as the pressure decreased consisted of a visible traveling wave traveling from the anode to the cathode followed by numerous, thin ( 1.6 mm) striations evenly spaced down the entire length of the positive column. These, shifted back toward the anode and transformed into bent striations with the tip of the 'V' pointing toward the cathode, and finally, the 'V' striations grouped into fours and took on the appearance of beats. The unusual 'V' striations may be due in part to a contraction of the column, causing the equipotential surfaces to shift from smooth convex to the observed striation shape. The conditions for this contraction effect include a nonlinearly increasing dependence of electron production rate on electron density and a bulk recombination rate higher than that at the tube walls. Visible emission spectra indicated the presence of carbon monoxide (CO), signifying that the striations are due to not only vibrational excitation of the ethanol molecule but also to decomposition and subsequent excitation of the decomposition products as well. One possible mechanism of decomposition is the formation of a radical cation from the ethanol molecule and the ensuing loss of a proton to yield formaldehyde; this then would follow an analogous decomposition to produce carbon monoxide. Thus, there may exist additional charged species which can then contribute to the unique observations. Further analysis, if possible, will include higher temporal resolution spectroscopy and a detailed model of the positive column under these specific conditions.

  19. Striated perineal muscles: location of autonomic, sensory, and somatic neurons projecting to the male pig bulbospongiosus muscle.

    PubMed

    Botti, Maddalena; Ragionieri, Luisa; Gazza, Ferdinando; Acone, Franca; Bo Minelli, Luisa; Panu, Rino

    2009-11-01

    The location, number, and size of the neurons innervating the bulbospongiosus muscle (BSM) were studied in male pigs, by means of Fast Blue (FB) retrograde transport. After injection of FB into the left BSM, labeled neurons were found bilaterally in the L2-S4 sympathetic trunk ganglia (STGs), in the caudal mesenteric ganglia (CMGs), in the microganglia of the pelvic plexus (PGs), in a dorsolateral area with respect to the central canal of S1-S3 segments of the spinal cord (SC) and in the S1-S4 ipsilateral and S2-S3 contralateral spinal ganglia (SGs). The mean number of labeled FB cells was 3,122 +/- 1,968 in STGs, 979 +/- 667 in CMGs, 108 +/- 104 in PGs, 89 +/- 39 in SC and 77 +/- 23 in SGs. The area of the multipolar neurons was 852 +/- 22 microm(2) in the STGs, 878 +/- 23 microm(2) in the CMGs and 922 +/- 31 microm(2) in the PGs. The multipolar SC neurons had an area of 1,057 +/- 38 microm(2), while pseudounipolar SG cells had dimensions of 2,281 +/- 129 microm(2). Our research enables us to highlight two peculiarities regarding the innervation of the boar BSM: the very high number of labeled autonomic neurons and the particular localization of the motor somatic nucleus. PMID:19718716

  20. Morphology and histology of chimpanzee primary visual striate cortex indicate that brain reorganization predated brain expansion in early hominid evolution.

    PubMed

    Holloway, Ralph L; Broadfield, Douglas C; Yuan, Michael S

    2003-07-01

    Human brain evolution is characterized by an overall increase in brain size, cerebral reorganization, and cerebral lateralization. It is generally understood when brain enlargement occurred during human evolution. However, issues concerning cerebral reorganization and hemispheric lateralization are more difficult to determine from brain endocasts, and they are topics of considerable debate. One region of the cerebral cortex that may represent the earliest evidence for brain reorganization is the primary visual cortex (PVC), or area 17 of Brodmann. In nonhuman primates, this region is larger in volume (demarcated anteriorly by the lunate sulcus), and extends further rostrally than it does in modern humans. In early hominid fossil (Australopithecus) endocasts, this region appears to occupy a smaller area compared to that in nonhuman primates. Some have argued that the brain first underwent size expansion prior to reorganization, while others maintain that reorganization predated brain expansion. To help resolve this question, we provide a description of two male, common chimpanzee (Pan troglodytes) brains, YN77-111 and YN92-115, which clearly display a more posterior lunate sulcal morphology than seen in other chimpanzees. These data show that neurogenetic variability exists in chimpanzees, and that significant differences in organization (e.g., a reduced PVC) can predate brain enlargement. While the human brain has experienced numerous expansion and reorganization events throughout evolution, the data from these two chimpanzees offer significant support for the hypothesis that the neurogenetic basis for brain reorganization was present in our early fossil ancestors (i.e., the australopithecines) prior to brain enlargement. PMID:12808644

  1. K201 (JTV519) is a Ca2+-Dependent Blocker of SERCA and a Partial Agonist of Ryanodine Receptors in Striated Muscle.

    PubMed

    Darcy, Yuanzhao L; Diaz-Sylvester, Paula L; Copello, Julio A

    2016-08-01

    K201 (JTV-519) may prevent abnormal Ca(2+) leak from the sarcoplasmic reticulum (SR) in the ischemic heart and skeletal muscle (SkM) by stabilizing the ryanodine receptors (RyRs; RyR1 and RyR2, respectively). We tested direct modulation of the SR Ca(2+)-stimulated ATPase (SERCA) and RyRs by K201. In isolated cardiac and SkM SR microsomes, K201 slowed the rate of SR Ca(2+) loading, suggesting potential SERCA block and/or RyR agonism. K201 displayed Ca(2+)-dependent inhibition of SERCA-dependent ATPase activity, which was measured in microsomes incubated with 200, 2, and 0.25 µM Ca(2+) and with the half-maximal K201 inhibitory doses (IC50) estimated at 130, 19, and 9 µM (cardiac muscle) and 104, 13, and 5 µM (SkM SR). K201 (≥5 µM) increased RyR1-mediated Ca(2+) release from SkM microsomes. Maximal K201 doses at 80 µM produced ∼37% of the increase in SkM SR Ca(2+) release observed with the RyR agonist caffeine. K201 (≥5 µM) increased the open probability (Po) of very active ("high-activity") RyR1 of SkM reconstituted into bilayers, but it had no effect on "low-activity" channels. Likewise, K201 activated cardiac RyR2 under systolic Ca(2+) conditions (∼5 µM; channels at Po ∼0.3) but not under diastolic Ca(2+) conditions (∼100 nM; Po < 0.01). Thus, K201-induced the inhibition of SR Ca(2+) leak found in cell-system studies may relate to potentially potent SERCA block under resting Ca(2+) conditions. SERCA block likely produces mild SR depletion in normal conditions but could prevent SR Ca(2+) overload under pathologic conditions, thus precluding abnormal RyR-mediated Ca(2+) release. PMID:27235390

  2. Beyond Discourse? Using Deleuze and Guattari's Schizoanalysis to Explore Affective Assemblages, Heterosexually Striated Space, and Lines of Flight Online and at School

    ERIC Educational Resources Information Center

    Ringrose, Jessica

    2011-01-01

    This paper explores how Deleuze and Guattari's philosophical concepts extend and elaborate discursive and psychoanalytic interpretations of qualitative research findings. Analyzing data from a UK research project exploring young people's engagements with Social Networking Sites (SNSs), Deleuze and Guattari's schizoanalytic method is drawn upon to…

  3. Cardinal difference between the orientation-selective retinal ganglion cells projecting to the fish tectum and the orientation-selective complex cells of the mammalian striate cortex.

    PubMed

    Damjanović, Ilija; Maximova, Elena; Maximov, Paul; Maximov, Vadim

    2012-06-01

    Responses from two types of orientation-selective units of retinal origin were recorded extracellularly from their axon terminals in the medial sublaminae of tectal retinorecipient layer of immobilized cyprinid fish Carassius gibelio. Excitatory and inhibitory interactions in the receptive field were analyzed with two narrow stripes of optimal orientation flashing synchronously, one in the center and the other in different parts of the periphery. The general pattern of results was that the influence of the remote peripheral stripe was inhibitory, irrespective of the polarity of each stripe (light or dark). In this regard, the orientation-selective ganglion cells of the fish retina differ from the classical orientation-selective complex cells of the mammalian cortex, where the remote paired stripes of the opposite polarity (one light and one dark) interact in a facilitatory fashion. The consequence of these differences may be a weaker lateral inhibition in the latter case in response to stimulation by periodic gratings, which may contribute to a better spatial frequency tuning in the visual cortex. PMID:22744823

  4. Filament lattice of frog striated muscle. Radial forces, lattice stability, and filament compression in the A-band of relaxed and rigor muscle.

    PubMed Central

    Millman, B M; Irving, T C

    1988-01-01

    Repulsive pressure in the A-band filament lattice of relaxed frog skeletal muscle has been measured as a function of interfilament spacing using an osmotic shrinking technique. Much improved chemical skinning was obtained when the muscles were equilibrated in the presence of EGTA before skinning. The lattice shrank with increasing external osmotic pressure. At any specific pressure, the lattice spacing in relaxed muscle was smaller than that of muscle in rigor, except at low pressures where the reverse was found. The lattice spacing was the same in the two states at a spacing close to that found in vivo. The data were consistent with an electrostatic repulsion over most of the pressure range. For relaxed muscle, the data lay close to electrostatic pressure curves for a thick filament charge diameter of approximately 26 nm, suggesting that charges stabilizing the lattice are situated about midway along the thick filament projections (HMM-S1). At low pressures, observed spacings were larger than calculated, consistent with the idea that thick filament projections move away from the filament backbone. Under all conditions studied, relaxed and rigor, at short and very long sarcomere lengths, the filament lattice could be modeled by assuming a repulsive electrostatic pressure, a weak attractive pressure, and a radial stiffness of the thick filaments (projections) that differed between relaxed and rigor conditions. Each thick filament projection could be compressed by approximately 5 or 2.6 nm requiring a force of 1.3 or 80 pN for relaxed and rigor conditions respectively. PMID:3264728

  5. The effects of Duvernoy's gland secretion from the xenodontine colubrid Philodryas olfersii on striated muscle and the neuromuscular junction: partial characterization of a neuromuscular fraction.

    PubMed

    Prado-Franceschi, J; Hyslop, S; Cogo, J C; Andrade, A L; Assakura, M; Cruz-Höfling, M A; Rodrigues-Simioni, L

    1996-04-01

    The effect of Philodryas olfersii Duvernoy's secretion was studied in vivo in mice and chicks as well as in the mouse phrenic nerve-diaphragm and the chick biventer cervicis preparations. The whole secretion (20-40 micrograms/ml) increased the creatine kinase (CK) levels in mice but had no effect on the mouse phrenic nerve-diaphragm preparation. In the chick, the secretion caused head drop and paresia as well as irreversible blockade of the twitch-tension evoked by indirect stimulation in the chick biventer cervicis preparation (50% paralysis in 34.5 +/- 2.7 min, n = 4). The secretion also caused muscle contracture (30% of the maximal twitch-tension generated) after a latency of nearly 9 min. Following fractionation on a Superose 12 FPLC column, the neuromuscular activity was recovered in the high mol. wt fraction (Peak I). At a concentration of 10 micrograms/ml in the chick biventer cervicis preparation, Peak I caused 50% paralysis within 18.5 +/- 3.0 min (n = 4), and evoked a strong contracture (70% of the maximal twitch-tension generated). The contractile responses of the chick preparation to ACh and KCL were partially blocked (90%) by the whole secretion and totally blocked by Peak I. CK release was increased by the whole secretion but not by Peak I. The whole secretion also produced various degrees of muscle cell lysis and extensive widening of the intercellular spaces. The latter showed a loosely arranged membranous network. In general, Peak I caused only minor morphological alterations compared with the whole secretion, although these were still significantly different from those observed in the control preparations. The changes principally involved hypercontraction of the muscle fibers. Based on the above results, we conclude that Peak I contains the factor(s) responsible for the in vitro effects on neuromuscular transmission, whereas the direct myotoxic effect is apparently caused by at least one other component of the Duvernoy's secretion. PMID:8735245

  6. Characterization of a myotoxin from the Duvernoy's gland secretion of the xenodontine colubrid Philodryas olfersii (green snake): effects on striated muscle and the neuromuscular junction.

    PubMed

    Prado-Franceschi, J; Hyslop, S; Cogo, J C; Andrade, A L; Assakura, M T; Reichl, A P; Cruz-Höfling, M A; Rodrigues-Simioni, L

    1998-10-01

    A myotoxin has been isolated from the Duvernoy's gland (DG) secretion of the xenodontine colubrid Philodrvas olfersii (green snake) by gel filtration on Sephadex G-100 SF. Under non-reducing and reducing conditions in SDS-PAGE, the myotoxin migrates as a single band with a mol. wt. of 20000. The toxin has 182 amino acid residues (approximately 20% acidic), a pI of 4.8 and a blocked N-terminal. In the chick biventer cervicis preparation, P. olfersii myotoxin partially blocks potassium-evoked contractures without affecting either the twitch-tension resulting from indirect stimulation or the contractures evoked by acetylcholine. Both the DG secretion and the myotoxin increase the serum creatine kinase (CK) levels of mice and stimulate the release of CK from the biventer cervicis preparation in a dose- and time-dependent manner. The varying degrees of muscle cell lysis and extensive widening of the intercellular spaces caused by the DG secretion are reproduced by the myotoxin, with the exception that in the latter the partial or total loss of transverse muscle striations is restricted to the muscle periphery. This myotoxin is the first such protein to be characterized from a DG secretion. PMID:9723839

  7. The cruciform model of striate generation of the early VEP, re-illustrated, not revoked: a reply to Ales et al. (2013).

    PubMed

    Kelly, Simon P; Vanegas, M Isabel; Schroeder, Charles E; Lalor, Edmund C

    2013-11-15

    Here we summarize the points raised in our dialog with Ales and colleagues on the cortical generators of the early visual evoked potential (VEP), and offer observations on the results of additional simulations that were run in response to our original comment. For small stimuli placed at locations in the upper and lower visual field for which the human VEP has been well characterized, simulated scalp projections of each of the visual areas V1, V2 and V3 invert in polarity. However, the empirically measured, earliest VEP component, "C1," matches the simulated V1 generators in terms of polarity and topography, but not the simulated V2 and V3 generators. We thus conclude that, 1) consistent with the title of Ales et al. (2010a), polarity inversion on its own is not a sufficient criterion for inferring neuroelectric sources in primary visual cortex; but 2) inconsistent with additional claims made in Ales et al. (2010a), the simulated topographies provide additional evidence for - not against - the tenet that the C1 component is generated in V1. PMID:23735259

  8. Insights into the internal structure and formation of striated fault surfaces of oceanic detachments from in situ observations (13°20'N and 13°30'N, Mid-Atlantic Ridge)

    NASA Astrophysics Data System (ADS)

    Escartin, J.; Bonnemains, D.; Mevel, C.; Cannat, M.; Petersen, S.; Augustin, N.; Bezos, A.; Chavagnac, V.; Choi, Y.; Godard, M.; Haaga, K.; Hamelin, C.; Ildefonse, B.; Jamieson, J. W.; John, B. E.; Leleu, T.; MacLeod, C. J.; Massot-Campos, M.; Nomikou, P.; Olive, J. A. L.; Paquet, M.; Rommevaux, C.; Rothenbeck, M.; Steinführer, A.; Tominaga, M.; Triebe, L.; Andreani, M.; Garcia, R.; Campos, R.

    2014-12-01

    Oceanic detachment faults (ODs) are known to play a significant role in oceanic crustal accretion along slow-spreading ridges, and many display a poorly understood corrugated fault surface. The ODEMAR cruise (Nov-Dec'14) studied the 13°20'N and 13°30'N ODs along the Mid-Atlantic Ridge via extensive microbathymetric surveys with AUV ABYSS (GEOMAR), combined with geological observations and sampling using ROV VICTOR (IFREMER). The 13°20'N OD is largely intact, with an undisrupted corrugated surface. An abrupt, continuous moat where the OD emerges from the seafloor sloping at ~12-18° continuously sheds rubble onto the OD fault plane, blanketing it. An apron surrounds the detachment dipping ~10-14° towards volcanic rift valley floor thus forming a thin wedge above the active OD fault, which uplifts hangingwall material. In contrast, the 13°30'N OD is cut by recent high-angle faults, and is likely inactive. The OD fault is well exposed along these recent high angle fault scarps, and along mass wasting scarps. The OD fault displays individual microbathymetric lineations throughout the >150 m of fault zone thickness, that are traced up to ~2 km in the spreading direction. Flanks of individual lineations display fault planes extending ~20-100 m laterally with well-developed, extension-parallel striae. At 13°20'N. These fault surfaces are primarily basalt fault breccias and minor serpentinite. At 13°30'N the scarps cutting the detachment system reveal highly heterogeneous deformation, with phacoidal blocks of undeformed peridotite, gabbro, and basalt enclosed in anastomosing shear zones. Basalt often shows greenschist grade alteration, and is only present in the upper 50 m of the OD fault zone. In detail, OD faults are characterized by anastomosing zones of localized, strongly anisotropic deformation at different scales (m to km), bounding bodies of largely undeformed rock (basalt, gabbro, peridotite) elongated in the extension direction. Hangingwall material (basalt and dolerite) gets reworked into the fault zone in the green schist facies and effectively accreted to the footwall, both as fault breccia and as large blocks within the fault. Such fine-scale, in situ observations provide unprecedented insights into the three-dimensional and heterogeneous strain localization at OD fault zones.

  9. Shatter Cones in Basalt: A Natural Example from the Vista Alegre Impact Structure, Brazil

    NASA Astrophysics Data System (ADS)

    Pittarello, L.; Nestola, F.; Viti, C.; Crósta, A. P.; Koeberl, C.

    2015-09-01

    Shatter cones, formed in fine-grained basalt in the Vista Alegre impact structure (Brazil), exhibit cataclastic layers sub-parallel to the striated surfaces and a continuous melt rock film, investigated with TEM, decorating the striated surface.

  10. Hand-Held Model of a Sarcomere to Illustrate the Sliding Filament Mechanism in Muscle Contraction

    ERIC Educational Resources Information Center

    Jittivadhna, Karnyupha; Ruenwongsa, Pintip; Panijpan, Bhinyo

    2009-01-01

    From our teaching of the contractile unit of the striated muscle, we have found limitations in using textbook illustrations of sarcomere structure and its related dynamic molecular physiological details. A hand-held model of a striated muscle sarcomere made from common items has thus been made by us to enhance students' understanding of the…

  11. Skeletal muscle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are approximately 650-850 muscles in the human body these include skeletal (striated), smooth and cardiac muscle. The approximation is based on what some anatomists consider separate muscle or muscle systems. Muscles are classified based on their anatomy (striated vs. smooth) and if they are v...

  12. Types of muscle tissue (image)

    MedlinePlus

    ... appear striated, and are under involuntary control. Smooth muscle fibers are located in walls of hollow visceral organs, ... shaped, and are also under involuntary control. Skeletal muscle fibers occur in muscles which are attached to the ...

  13. Types of muscle tissue (image)

    MedlinePlus

    The 3 types of muscle tissue are cardiac, smooth, and skeletal. Cardiac muscle cells are located in the walls of the heart, appear striated, and are under involuntary control. Smooth muscle fibers are located in walls of hollow ...

  14. Shatter Cones from the MEMIN Impact Experiments

    NASA Astrophysics Data System (ADS)

    Wilk, J.; Kenkmann, T.

    2015-09-01

    We recovered shatter cone fragments from the MEMIN cratering experiments in sandstone, quartzite and limestone blocks. We analyzed the conical to hyperboloid, curved and striated fracture surfaces with SEM, WLI and produced µm-accurate 3D models.

  15. Formation of Shatter Cones in the MEMIN Impact Experiments

    NASA Astrophysics Data System (ADS)

    Wilk, J.; Kenkmann, T.

    2015-07-01

    We recovered shatter cone fragments from the MEMIN cratering experiments in sandstone, quartzite and limestone blocks. We analyzed the conical to hyperboloid, curved and striated fracture surfaces with SEM, WLI and produced µm-accurate 3D models.

  16. Toolmark identification of a mattock to a clod of soil from a grave.

    PubMed

    Clark, Michael D

    2011-01-01

    At a recent bushland gravesite that contained a deceased male, a clod of soil displaying a striated toolmark was collected during the excavation of the grave. This clod was preserved, and the mark was cast using Mikrosil™. Shovels and a mattock, which had been discarded by the suspects, were subsequently found at another location. A toolmark comparison identified the hoe end of the mattock head as having produced the striated toolmark. PMID:20735700

  17. Host Chemical Footprints Induce Host Sex Discrimination Ability in Egg Parasitoids

    PubMed Central

    Peri, Ezio; Frati, Francesca; Salerno, Gianandrea; Conti, Eric; Colazza, Stefano

    2013-01-01

    Trissolcus egg parasitoids, when perceiving the chemical footprints left on a substrate by pentatomid host bugs, adopt a motivated searching behaviour characterized by longer searching time on patches were signals are present. Once in contact with host chemical footprints, Trissolcus wasps search longer on traces left by associated hosts rather than non-associated species, and, in the former case, they search longer on traces left by females than males. Based on these evidences, we hypothesized that only associated hosts induce the ability to discriminate host sex in wasps. To test this hypothesis we investigated the ability of Trissolcus basalis, T. brochymenae, and Trissolcus sp. to distinguish female from male Nezara viridula, Murgantia histrionica, and Graphosoma semipunctatum footprints. These three pentatomid bugs were selected according to variable association levels. Bioassays were conducted on filter paper sheets, and on Brassica oleracea (broccoli) leaves. The results confirmed our hypothesis showing that wasps spent significantly more time on female rather than male traces left by associated hosts on both substrates. No differences were observed in the presence of traces left by non-associated hosts. The ecological consequences for parasitoid host location behaviour are discussed. PMID:24244417

  18. Translational control of tropomyosin expression in vertebrate hearts.

    PubMed

    Dube, Dipak K; McLean, Matthew D; Dube, Syamalima; Poiesz, Bernard J

    2014-09-01

    The tropomyosin (TM) gene family produces a set of related TM proteins with important functions in striated and smooth muscle, and nonmuscle cells. In vertebrate striated muscle, the thin filament consists largely of actin, TM, the troponin (Tn) complex (Tn-I, Tn-C and Tn-T), and tropomodulin (Tmod) and is responsible for mediating Ca(2+) control of muscle contraction and relaxation. There are four known genes (designated as TPM1, TPM2, TPM3, and TPM4) for TM in vertebrates. The four TM genes generate a multitude of tissue- and developmental-specific isoforms through the use of different promoters, alternative mRNA splicing, different 3'-end mRNA processing and tissue-specific translational control. In this review, we have focused mainly on the regulation of TM expression in striated muscles, primarily in vertebrate hearts with special emphasis on translational control using mouse and Mexican axolotl animal models. PMID:25125172

  19. Proteomics Unveils Fibroblast-Cardiomyocyte Lactate Shuttle and Hexokinase Paradox in Mouse Muscles.

    PubMed

    Rakus, Dariusz; Gizak, Agnieszka; Wiśniewski, Jacek R

    2016-08-01

    Quantitative mapping, given in biochemically interpretable units such as mol per mg of total protein, of tissue-specific proteomes is prerequisite for the analysis of any process in cells. We applied label- and standard-free proteomics to characterize three types of striated muscles: white, red, and cardiac muscle. The analysis presented here uncovers several unexpected and novel features of striated muscles. In addition to differences in protein expression levels, the three muscle types substantially differ in their patterns of basic metabolic pathways and isoforms of regulatory proteins. Importantly, some of the conclusions drawn on the basis of our results, such as the potential existence of a "fibroblast-cardiomyocyte lactate shuttle" and the "hexokinase paradox" point to the necessity of reinterpretation of some basic aspects of striated muscle metabolism. The data presented here constitute a powerful database and a resource for future studies of muscle physiology and for the design of pharmaceutics for the treatment of muscular disorders. PMID:27302655

  20. Chronic Sarcocystis infections in slaughtered cattle.

    PubMed

    Saito, M; Mizusawa, K; Itagaki, H

    1993-10-01

    Parasitological, histopathological and immunohistochemical examinations were carried out on three slaughtered cattle with many nodules in all the striated muscles. At necropsy, many yellowish green rice-grain sized nodules including cheesy contents were observed in all the striated muscles. Histopathologically the nodules were granuloma principally consisting of eosinophiles. No Sarcocystis cysts nor bradyzoites were found in the nodules, but intact sarcocysts were found in the normal tissues surrounding the nodules. The central necrotic focus of nodules showed intense positive responses against anti-Sarcocystis cruzi rabbit serum by immunohistochemical examination. From the above findings the slaughtered cattle were diagnosed as chronic sarcocystiasis. PMID:8286527

  1. Two distinct myosin II populations coordinate ovulatory contraction of the myoepithelial sheath in the Caenorhabditis elegans somatic gonad

    PubMed Central

    Ono, Kanako; Ono, Shoichiro

    2016-01-01

    The myoepithelial sheath in the somatic gonad of the nematode Caenorhabditis elegans has nonstriated contractile actomyosin networks that produce highly coordinated contractility for ovulation of mature oocytes. Two myosin heavy chains are expressed in the myoepithelial sheath, which are also expressed in the body-wall striated muscle. The troponin/tropomyosin system is also present and essential for ovulation. Therefore, although the myoepithelial sheath has smooth muscle–like contractile apparatuses, it has a striated muscle–like regulatory mechanism through troponin/tropomyosin. Here we report that the myoepithelial sheath has a distinct myosin population containing nonmuscle myosin II isoforms, which is regulated by phosphorylation and essential for ovulation. MLC-4, a nonmuscle myosin regulatory light chain, localizes to small punctate structures and does not colocalize with large, needle-like myosin filaments containing MYO-3, a striated-muscle myosin isoform. RNA interference of MLC-4, as well as of its upstream regulators, LET-502 (Rho-associated coiled-coil forming kinase) and MEL-11 (a myosin-binding subunit of myosin phosphatase), impairs ovulation. Expression of a phosphomimetic MLC-4 mutant mimicking a constitutively active state also impairs ovulation. A striated-muscle myosin (UNC-54) appears to provide partially compensatory contractility. Thus the results indicate that the two spatially distinct myosin II populations coordinately regulate ovulatory contraction of the myoepithelial sheath. PMID:26864628

  2. Subcortical Modulation of Spatial Attention Including Evidence that the Sprague Effect Extends to Man

    ERIC Educational Resources Information Center

    Weddell, Rodger A.

    2004-01-01

    The Sprague effect is well-established--small tectal lesions restore visual orientation in the hemianopic field of animals with extensive unilateral geniculo-striate lesions. Studies of human midbrain visual functions are rare. This man with a midbrain tumour developed left-neglect through subsequent right frontal damage. Bilateral orientation…

  3. Early visual cortical responses produced by checkerboard pattern stimulation.

    PubMed

    Shigihara, Yoshihito; Hoshi, Hideyuki; Zeki, Semir

    2016-07-01

    Visual evoked potentials have been traditionally triggered with flash or reversing checkerboard stimuli and recorded with electroencephalographic techniques, largely but not exclusively in clinical or clinically related settings. They have been crucial in determining the healthy functioning or otherwise of the visual pathways up to and including the cerebral cortex. They have typically given early response latencies of 100ms, the source of which has been attributed to V1, with the prestriate cortex being secondarily activated somewhat later. On the other hand, magnetoencephalographic studies using stimuli better tailored to the physiology of individual, specialized, visual areas have given early latencies of <50ms with the sources localized in both striate (V1) and prestriate cortex. In this study, we used the reversing checkerboard pattern as a stimulus and recorded cortical visual evoked magnetic fields with magnetoencephalography, to establish whether very early responses can be traced to (estimated) in both striate and prestriate cortex, since such a demonstration would enhance considerably the power of this classical approach in clinical investigations. Our results show that cortical responses evoked by checkerboard patterns can be detected before 50ms post-stimulus onset and that their sources can be estimated in both striate and prestriate cortex, suggesting a strong parallel input from the sub-cortex to both striate and prestriate divisions of the visual cortex. PMID:27083528

  4. New evidence for mid-Pliocene-early Pleistocene glaciation in the northern Patagonian Andes Argentina

    SciTech Connect

    Stephens, G.C.; Evenson, E.B.; Rabassa, J.

    1985-01-01

    Mount Tronador is an extinct, glacially eroded strato-volcano located in the northern Patagonian Andes. With a summit elevation of 3556 m, Mount Tronador lies mostly above the present regional snowline (2000 m) and is largely covered by extensive snow fields and glaciers. The rocks of Mount Tronador comprise the Tronador Formation, a 2000 m thick sequence of interlayered basalts, andesites, ignimbrites, agglomerates, volcanic mudflows and lahars. This volcanic edifice is built on an erosional land surface of Tertiary age. Three K-Ar dates from the Tronador Formation yield radiometric ages of 3.2, 0.34 and 0.18 m.y. Striated clasts have been found included in several large glacial boulders derived from volcanic mudflows and lahars of the Tronador Fm. These boulders have been eroded by the Rio Manso Glacier and deposited in its Neoglacial moraines. The lahar boulders themselves contain pebbles and boulders of andesitic rocks in a vitroclastic matrix of pyroclastic origin. The striated clasts are well-rounded, shaped and polished, and the striations can be traced beneath the volcanic matrix. Thus these striated clasts represent a pre-Holocene cycle of glaciation. Mercer (1976) and Ciesielski (1982) document glaciations from southern Patagonia (2.1-3.5 m.y.) and from the southwestern Atlantic (2.1-3.9 m.y.) respectively. The discovery of striated clasts in lahars and mudflows of the Tronador Fm. indicates the existence of a heretofore undocumented Pliocene-Pleistocene glaciation in northern Patagonia.

  5. Improving Generalisation Skills in a Neural Network on the Basis of Neurophysiological Data

    ERIC Educational Resources Information Center

    Mermillod, M.; Chauvin, A.; Guyader, N.

    2005-01-01

    The distribution of striate cortex cells exhibits a maximum number of cells tuned to vertical and horizontal orientations (Mansfield, 1974). This was interpreted as an adaptation of the visual system to the presence in the visual environment of greater amounts of vertical and horizontal information compared to information from other orientations…

  6. Biofeedback for Developing Self-Control of Tension and Stress in One's Hierarchy of Psychological States.

    ERIC Educational Resources Information Center

    Cassel, Russell

    1985-01-01

    Describes six stage hierarchial patterns in the development of self-control through biofeedback. The stages include Skeletal and Striated Muscle Tension; Visceral Involvement-Anxiety Neuroses; Chronic Physiological Dysfunctioning; Decision Making Competency; Twilight Learning-Permissive Concentration; and Autogenic Feedback Training. (BL)

  7. Two distinct myosin II populations coordinate ovulatory contraction of the myoepithelial sheath in the Caenorhabditis elegans somatic gonad.

    PubMed

    Ono, Kanako; Ono, Shoichiro

    2016-04-01

    The myoepithelial sheath in the somatic gonad of the nematodeCaenorhabditis eleganshas nonstriated contractile actomyosin networks that produce highly coordinated contractility for ovulation of mature oocytes. Two myosin heavy chains are expressed in the myoepithelial sheath, which are also expressed in the body-wall striated muscle. The troponin/tropomyosin system is also present and essential for ovulation. Therefore, although the myoepithelial sheath has smooth muscle-like contractile apparatuses, it has a striated muscle-like regulatory mechanism through troponin/tropomyosin. Here we report that the myoepithelial sheath has a distinct myosin population containing nonmuscle myosin II isoforms, which is regulated by phosphorylation and essential for ovulation. MLC-4, a nonmuscle myosin regulatory light chain, localizes to small punctate structures and does not colocalize with large, needle-like myosin filaments containing MYO-3, a striated-muscle myosin isoform. RNA interference of MLC-4, as well as of its upstream regulators, LET-502 (Rho-associated coiled-coil forming kinase) and MEL-11 (a myosin-binding subunit of myosin phosphatase), impairs ovulation. Expression of a phosphomimetic MLC-4 mutant mimicking a constitutively active state also impairs ovulation. A striated-muscle myosin (UNC-54) appears to provide partially compensatory contractility. Thus the results indicate that the two spatially distinct myosin II populations coordinately regulate ovulatory contraction of the myoepithelial sheath. PMID:26864628

  8. The Development of Luminance- and Texture-Defined Form Perception during the School-Aged Years

    ERIC Educational Resources Information Center

    Bertone, Armando; Hanck, Julie; Guy, Jacalyn; Cornish, Kim

    2010-01-01

    The objective of the present study was to assess the development of luminance- and texture-defined static form perception in school-aged children. This was done using an adapted Landolt-C technique where C-optotypes were defined by either luminance or texture information, the latter necessitating extra-striate neural processing to be perceived.…

  9. Smoothness and Striation in Digital Learning Spaces

    ERIC Educational Resources Information Center

    Bayne, Sian

    2004-01-01

    It is Deleuze & Guattari's description of smooth and striated cultural spaces (Deleuze & Guattari, 1988) which informs this exploration of pedagogical alternatives within the learning environments of cyberspace. Digital spaces work to constitute subject and text in ways which are distinct, and it is awareness of this distinctiveness which must…

  10. Nomads with Maps: Musical Connections in a Glocalized World

    ERIC Educational Resources Information Center

    Richerme, Lauren Kapalka

    2013-01-01

    This article presents the author's views on the concepts of the philosophers Deleuze and Guattari on striated (sedentary) space and smooth (mobile) space, asserting that "nomads" can move freely about their space. She relates these concepts to music education, incorporating Deleuze and Guattari's concept of mapping as it…

  11. Uncoupling activity of the anthelmintic oxyclozanide in rodents

    PubMed Central

    Veenendaal, G.H.; De Waal, M.J.

    1974-01-01

    The uncoupling activity of oxyclozanide in warm blooded animals has been studied in whole animals, isolated tissue in vitro and on mitochondrial preparations. The onset of post mortem rigidity in mice and rats is accelerated and a contracture of striated muscle is produced. Oxyclozanide (1 μM) stimulated rat liver mitochondrial respiration and stimulated an ATP-ase activity. PMID:4277750

  12. Revision of the Genus Corallomycetella with Corallonectria gen. nov. for C. jatrophae (Nectriaceae, Hypocreales)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Corallomycetella (Ascomycota, Sordariomycetes, Hypocreales, Nectriaceae) has been defined to include red nectrioid fungi associated with rhizomorphs in nature and culture. With the recent collection of an unusual specimen having striated ascospores, the genus was re-examined using this and...

  13. Anatomic basis for the continence-preserving radical retropubic prostatectomy.

    PubMed

    Steiner, M S

    2000-02-01

    The technique of continence-preserving anatomic radical retropubic prostatectomy focuses on the preservation of the following anatomic components of the external striated urethral sphincteric complex: (1) the entire circumference of the rhabdosphincter musculature, (2) the periurethral fascial investments (the pubourethral ligaments anterolaterally and median fibrous raphe posteriorly), and (3) the innervation of both the rhabdosphincter by way of the intrapelvic branch of the pudendal nerve (somatic) and the mucosal and smooth muscle components by way of the urethral branch of the inferior hypogastric plexus (autonomic). The clinical impact of preserving the external striated urethral sphincter and its innervation by performing a continence preserving anatomic retropubic prostatectomy is a shorter time to achieve urinary continence. PMID:10719925

  14. Heidenhain variant of Creutzfeldt-Jakob disease: An autopsy study from India.

    PubMed

    Kher, Monica; Rao, Medha Y; Acharya, P T; Mahadevan, Anita; Shankar, S K

    2009-01-01

    Prion diseases are rare, progressive and fatal neurodegenerative diseases characterized by long incubation period and short clinical course. We present a rare case of Heidenhain variant of Creutzfeldt-Jakob disease, occurring in a 55-year-old lady presenting with dementia, cortical blindness, and myoclonic jerks. She succumbed to the disease within 8 weeks of onset of symptoms. MRI revealed hyperintense signals on T2WI and fluid attenuated inversion recovery (FLAIR) images in basal ganglia and fronto-temporal and parietal cortex, sparing thalamus, striate cortex and globus pallidum. Abundant abnormal prion protein deposits (PrP(sc)) were detected in caudate, putamen, thalamus, cingulate and striate cortex, in comparison to frontal and parietal cortex while no deposits were found in globus pallidum. MRI changes did not correlate with degree of spongy change, gliosis or prion protein deposition. The cause for abnormal signal changes in MRI and FLAIR images remains unclear. PMID:20151011

  15. Detyrosinated microtubules modulate mechanotransduction in heart and skeletal muscle

    PubMed Central

    Kerr, Jaclyn P.; Robison, Patrick; Shi, Guoli; Bogush, Alexey I.; Kempema, Aaron M.; Hexum, Joseph K.; Becerra, Natalia; Harki, Daniel A.; Martin, Stuart S.; Raiteri, Roberto; Prosser, Benjamin L.; Ward, Christopher W.

    2015-01-01

    In striated muscle, X-ROS is the mechanotransduction pathway by which mechanical stress transduced by the microtubule network elicits reactive oxygen species. X-ROS tunes Ca2+ signalling in healthy muscle, but in diseases such as Duchenne muscular dystrophy (DMD), microtubule alterations drive elevated X-ROS, disrupting Ca2+ homeostasis and impairing function. Here we show that detyrosination, a post-translational modification of α-tubulin, influences X-ROS signalling, contraction speed and cytoskeletal mechanics. In the mdx mouse model of DMD, the pharmacological reduction of detyrosination in vitro ablates aberrant X-ROS and Ca2+ signalling, and in vivo it protects against hallmarks of DMD, including workload-induced arrhythmias and contraction-induced injury in skeletal muscle. We conclude that detyrosinated microtubules increase cytoskeletal stiffness and mechanotransduction in striated muscle and that targeting this post-translational modification may have broad therapeutic potential in muscular dystrophies. PMID:26446751

  16. Mapping of functional activity in brain with /sup 18/F-fluoro-deoxyglucose

    SciTech Connect

    Alavi, A.; Reivich, M.; Greenberg, J.; Hand, P.; Rosenquist, A.; Rintelmann, W.; Christman, D.; Fowler, J.; Goldman, A.; MacGregor, R.; Wolf, A.

    1981-01-01

    The efficacy of using the /sup 18/F-fluoro-deoxyglucose (/sup 18/F-DG) for measuring regional cerebral glucose utilization in man during functional activation is demonstrated. Normal male volunteers subjected to sensory stimuli (visual, auditory, tactile) exhibited focal increases in glucose metabolism in response to the stimulus. Unilateral visual hemifield stimulation caused the contralateral striate cortex to become more active metabolically than the striate cortex ipsilateral to the stimulated hemifield. Similarly, stroking of the fingers and hand of one arm with a brush produced an increase in metabolism in the contralateral postcentral gyrus compared to the homologous ipsilateral region. The auditory stimulus, which consisted of monaural listening to either a meaningful or nonmeaningful story, caused an increase in glucose metabolism in the right temporal cortex independent of which ear was stimulated. These results demonstrate that the /sup 18/F-DG technique is capable of providing functional maps in vivo in the human brain.

  17. Sarcocystis fayeri-Induced Granulomatous and Eosinophilic Myositis in 2 Related Horses.

    PubMed

    Herd, H R; Sula, M M; Starkey, L A; Panciera, R J; Johnson, E M; Snider, T A; Holbrook, T C

    2015-11-01

    This report describes 2 genetically related paint mares, case Nos. 1 and 2, presented to the Oklahoma State University Boren Veterinary Medical Teaching Hospital for chronic weight loss and abnormal gait, respectively. Notable findings in both cases included marked persistent eosinophilia and multiple intramuscular lateral thoracic masses. Histologic examination of masses revealed eosinophilic, centrally necrotic granulomas and marked eosinophilic myositis. Granulomas in case No. 1 also contained intralesional Sarcocystis sp material, and adjacent muscle fibers contained intact protozoal cysts. Case No. 1 developed severe refractory muscle pain and recurrent esophageal dysphagia. At necropsy, disseminated, grossly visible granulomas were present throughout all examined striated muscles. Nested polymerase chain reaction of the 18S rRNA gene revealed >99% homology with Sarcocystis fayeri. Sarcocystis spp are apicomplexan protozoa that infect striated muscle of many omnivorous species, typically without inciting clinical disease. Sarcocystosis should be considered a rare cause of granulomatous eosinophilic myositis and choke in horses. PMID:25957356

  18. Season related ultrastructural features of the parotid, submandibular and von Ebner's glands in hibernating bats.

    PubMed

    Azzali, G; Grandi, D

    1996-08-01

    The parotid, submandibular and the von Ebner's salivary glands of hibernating insectivorous bats (Pipistrellus pipistrellus, Rhinolophus f. e. and Eptesicus serotinus) were studied by transmission electron microscopy and by histochemical methods during various seasons of the year. We report the seasonal ultrastructural changes that occur in the cytoplasmic organelles and the secretory granules of the serous and mucous cells and in the intercalated and striated ducts of the major glands. It previously has been hypothesized that the heterogeneity of the inclusions in the serous granules is closely related to the varying seasonal levels of proteinaceous and glycidic constituents. Lymphatic vessels are present only in the perivascular and periductal connective tissue. Morphofunctional and comparative studies seem to confirm a relationship between secretory activity and nutritional status as well as a likely involvement of the intercalated and striated ducts in determining the composition of the saliva. PMID:8874091

  19. Electron microscopy of the intestine of the African lungfish, Protopterus aethiopicus.

    PubMed

    Purkerson, M L; Jarvis, J U; Luse, S A; Dempsey, E W

    1975-05-01

    Electron microscopic observations are reported on the intestine of the African lungfish, Protopterus aethiopicus. The lungfish has a spiral valve rather than a true stomach. Segments of mucosa from this area reveal, by transmission microscopy, that most cells have distinct striated borders with parallel microvilli. Fibrils within the core of the microvilli extend deeply into the cytoplasm. Microvilli on the surface of goblet cells are less regularly arranged than those of absorptive cells. Interspersed among the cells with striated borders are cells, similar in cytologic appearance except that they are covered with tufts of kinetocilia. By transmission electron microscopy, abnormal cilia having one complete complement of microtubules plus incomplete sets from other cilia which share some of the peripheral doublets of the complete cilium are enclosed by a single membrane. Cilia are usual in the intestine of many lower forms but ordinarily absent in higher vertebrates. Their functional significance in this primitive fish is unknown. PMID:1155792

  20. Permian Triassic palynofloral transition in Chintalapudi area, Godavari Graben, Andhra Pradesh, India

    NASA Astrophysics Data System (ADS)

    Jha, Neerja; Chary, M. Basava; Aggarwal, Neha

    2012-10-01

    The entire 606 m-thick sedimentary sequence in borecore MCP-7 from Chintalapudi area, Chintalapudi sub-basin has been lithologically designated as Kamthi Formation. However, the palynological investigation revealed five distinct palynoassemblages, which essentially fall under two groups, one group (Palynoassemblage-I, II and III) having dominance of striate disaccates along with presence of some stratigraphically significant taxa, belongs to Late Permian (Raniganj) palynoflora, while the other group (Palynoassemblages IV and V) shows sharp decline in percentage of characteristic taxa of first group, i.e., striate disaccates, and consequent rise or dominance of taeniate and cingulate cavate spores, belongs to Early Triassic (Panchet) palynoflora. Palynoassemblage-I, II and III (Group I) are characterized by dominance of striate disaccates chiefly, Striatopodocarpites spp. and Faunipollenites spp. along with presence of rare but stratigraphically significant taxa, viz., Gondisporites raniganjensis, Falcisporites nuthaliensis, Klausipollenites schaubergeri, Chordasporites sp., Striomonosaccites, ovatus, Crescentipollenites multistriatus, Verticipollenites debiles, Strotersporites crassiletus, Guttulapollenites hannonicus, G. gondwanensis, Hamiapollenites insolitus, Corisaccites alutus, Lunatisporites ovatus, Weylandites spp. and Vitreisporites pallidus. Palynoassemblage-I is distinguished by significant presence of Densipollenites spp. while Palynoassemblage-II shows significant presence of Crescentipollenites spp. and Palynoassemblage-III differs from the above two assemblages in having significant presence of Guttulapollenites hannonicus. Palynoassemblage-IV (Group II) is characterized by high percentage of taeniate disaccates chiefly Lunatisporites spp., while Palynoassemblage-V (Group II) is characterized by cingulate-cavate trilete spores chiefly, Lundbladispora spp. and Densoisporites spp. Striate disaccates show a sharp decline in these two assemblages. In

  1. Visual reactions in a case of long-lasting cortical blindness

    PubMed Central

    Braak, J. W. G. Ter; Schenk, V. W. D.; Vliet, A. G. M. Van

    1971-01-01

    A case is described of long-lasting cortical blindness in a 71 year old man showing no other visual reactions than pupillary narrowing to light and (only after some months) optokinetic nystagmus of the `passive' type. Necropsy demonstrated total bilateral destruction of the striate area of the cortex caused by bilateral softening in the territory of the posterior cerebral artery, and nearly total loss of ganglion cells in both lateral geniculate bodies. Images

  2. Gene regulation, alternative splicing, and posttranslational modification of troponin subunits in cardiac development and adaptation: a focused review

    PubMed Central

    Sheng, Juan-Juan; Jin, Jian-Ping

    2014-01-01

    Troponin plays a central role in regulating the contraction and relaxation of vertebrate striated muscles. This review focuses on the isoform gene regulation, alternative RNA splicing, and posttranslational modifications of troponin subunits in cardiac development and adaptation. Transcriptional and posttranscriptional regulations such as phosphorylation and proteolysis modifications, and structure-function relationships of troponin subunit proteins are summarized. The physiological and pathophysiological significances are discussed for impacts on cardiac muscle contractility, heart function, and adaptations in health and diseases. PMID:24817852

  3. Gravity and the cells of gravity receptors in mammals

    NASA Astrophysics Data System (ADS)

    Ross, M. D.

    Two new findings, that crystals located in the inner ear gravity receptors of mammals have the internal organization requisite for the piezoelectric property, and that sensory hair cells of these same receptors possess contractile-appearing striated organelles, have prompted the author to model mammalian gravity receptors in the ear on the principles of piezoelectricity and bioenergetics. This model is presented and a brief discussion of its implications for the possible effects of weightlessness follows.

  4. Titin: central player of hypertrophic signaling and sarcomeric protein quality control.

    PubMed

    Kötter, Sebastian; Andresen, Christian; Krüger, Martina

    2014-11-01

    The giant sarcomeric protein titin has multiple important functions in striated muscle cells. Due to its gigantic size, its central position in the sarcomere and its elastic I-band domains, titin is a scaffold protein that is important for sarcomere assembly, and serves as a molecular spring that defines myofilament distensibility. This review focuses on the emerging role of titin in mechanosensing and hypertrophic signaling, and further highlights recent evidence that links titin to sarcomeric protein turnover. PMID:25205716

  5. Mullerian adenosarcoma of the cervix with heterologous elements and sarcomatous overgrowth

    PubMed Central

    Pinto, Karen R.

    2016-01-01

    Cervical adenosarcomas are exceedingly infrequent tumors that occur most often in women of reproductive age. Adenosarcomas comprise benign epithelial elements and malignant stromal elements. The malignant stromal elements can either be homologous, such as fibroblasts or smooth muscle, or heterologous, like cartilage, striated muscle, or bone. We report a case of adenosarcoma of the cervix with heterologous elements and sarcomatous overgrowth in a 38-year-old woman. PMID:26722175

  6. Muscle as a “Mediator“ of Systemic Metabolism

    PubMed Central

    Baskin, Kedryn K.; Winders, Benjamin R.; Olson, Eric N.

    2015-01-01

    Skeletal and cardiac muscles play key roles in the regulation of systemic energy homeostasis and display remarkable plasticity in their metabolic responses to caloric availability and physical activity. In this Perspective we discuss recent studies highlighting transcriptional mechanisms that govern systemic metabolism by striated muscles. We focus on the participation of the Mediator complex in this process, and suggest that tissue-specific regulation of Mediator subunits impacts metabolic homeostasis. PMID:25651178

  7. Incidental finding of a microsporidian parasite from an AIDS patient.

    PubMed Central

    McDougall, R J; Tandy, M W; Boreham, R E; Stenzel, D J; O'Donoghue, P J

    1993-01-01

    Light microscopic examination of feces from a human immunodeficiency virus-positive patient with chronic diarrhea, anorexia, and lethargy revealed the presence of numerous refractile bodies resembling microsporidian spores. They were subsequently identified as belonging to the genus Nosema on the basis of their ultrastructural characteristics. However, the microsporidia were enclosed within striated muscle cells, suggesting that they were probably ingested in food; thus, this represented an incidental finding rather than a true infection. Images PMID:8432833

  8. Mechanical Properties of Respiratory Muscles

    PubMed Central

    Sieck, Gary C.; Ferreira, Leonardo F.; Reid, Michael B.; Mantilla, Carlos B.

    2014-01-01

    Striated respiratory muscles are necessary for lung ventilation and to maintain the patency of the upper airway. The basic structural and functional properties of respiratory muscles are similar to those of other striated muscles (both skeletal and cardiac). The sarcomere is the fundamental organizational unit of striated muscles and sarcomeric proteins underlie the passive and active mechanical properties of muscle fibers. In this respect, the functional categorization of different fiber types provides a conceptual framework to understand the physiological properties of respiratory muscles. Within the sarcomere, the interaction between the thick and thin filaments at the level of cross-bridges provides the elementary unit of force generation and contraction. Key to an understanding of the unique functional differences across muscle fiber types are differences in cross-bridge recruitment and cycling that relate to the expression of different myosin heavy chain isoforms in the thick filament. The active mechanical properties of muscle fibers are characterized by the relationship between myoplasmic Ca2+ and cross-bridge recruitment, force generation and sarcomere length (also cross-bridge recruitment), external load and shortening velocity (cross-bridge cycling rate), and cross-bridge cycling rate and ATP consumption. Passive mechanical properties are also important reflecting viscoelastic elements within sarcomeres as well as the extracellular matrix. Conditions that affect respiratory muscle performance may have a range of underlying pathophysiological causes, but their manifestations will depend on their impact on these basic elemental structures. PMID:24265238

  9. Impact of aging on mitochondrial function in cardiac and skeletal muscle.

    PubMed

    Hepple, R T

    2016-09-01

    Both skeletal muscle and cardiac muscle are subject to marked structural and functional impairment with aging and these changes contribute to the reduced capacity for exercise as we age. Since mitochondria are involved in multiple aspects of cellular homeostasis including energetics, reactive oxygen species signaling, and regulation of intrinsic apoptotic pathways, defects in this organelle are frequently implicated in the deterioration of skeletal and cardiac muscle with aging. On this basis, the purpose of this review is to evaluate the evidence that aging causes dysfunction in mitochondria in striated muscle with a view towards drawing conclusions about the potential of these changes to contribute to the deterioration seen in striated muscle with aging. As will be shown, impairment in respiration and reactive oxygen species emission with aging are highly variable between studies and seem to be largely a consequence of physical inactivity. On the other hand, both skeletal and cardiac muscle mitochondria are more susceptible to permeability transition and this seems a likely cause of the increased recruitment of mitochondrial-mediated pathways of apoptosis seen in striated muscle. The review concludes by examining the role of degeneration of mitochondrial DNA versus impaired mitochondrial quality control mechanisms in the accumulation of mitochondria that are sensitized to permeability transition, whereby the latter mechanism is favored as the most likely cause. PMID:27033952

  10. Morphological and molecular description of three new species of the cyrtophorid genus Chlamydodon (Ciliophora, Cyrtophoria).

    PubMed

    Pan, Hongbo; Li, Lifang; Al-Rasheid, Khaled A S; Song, Weibo

    2013-01-01

    This study investigates the morphology and molecular characteristics of three new cyrtophorid ciliates isolated from China seas: Chlamydodon salinus n. sp., Chlamydodon caudatus n. sp., and Chlamydodon paramnemosyne n. sp. Of these, C. salinus n. sp. differs from its congeners through a combination of body size, a cross-striated band that is not continuous, the presence of 30-34 somatic kineties, 11-15 nematodesmal rods, and 13 contractile vacuoles. Chlamydodon caudatus n. sp., meanwhile, is characterized by having a conspicuous tail, a continuous cross-striated band, 34-40 somatic kineties, about 15 contractile vacuoles, and 20-24 nematodesmal rods. Compared with other Chlamydodon species, the third new one, C. paramnemosyne n. sp., could be identified by its continuous cross-striated band, 16-18 somatic kineties, 5 contractile vacuoles, and 9-12 nematodesmal rods. Based on the sequence of the small subunit (SSU) rRNA gene, the phylogeny of these three new species was analyzed, indicating that they all clustered with other congeners to form a monophyletic assemblage. Based on previous studies and the present work, a brief revision of the genus Chlamydodon is supplied, and a key to aid the identification of Chlamydodon species is given. PMID:23289638

  11. X-Tream: a novel dosimetry system for Synchrotron Microbeam Radiation Therapy

    NASA Astrophysics Data System (ADS)

    Petasecca, M.; Cullen, A.; Fuduli, I.; Espinoza, A.; Porumb, C.; Stanton, C.; Aldosari, A. H.; Bräuer-Krisch, E.; Requardt, H.; Bravin, A.; Perevertaylo, V.; Rosenfeld, A. B.; Lerch, M. L. F.

    2012-07-01

    Microbeam Radiation Therapy (MRT) is a radiation treatment technique under development for inoperable brain tumors. MRT is based on the use of a synchrotron generated X-ray beam with an extremely high dose rate ( ~ 20 kGy/sec), striated into an array of X-ray micro-blades. In order to advance to clinical trials, a real-time dosimeter with excellent spatial resolution must be developed for absolute dosimetry. The design of a real-time dosimeter for such a radiation scenario represents a significant challenge due to the high photon flux and vertically striated radiation field, leading to very steep lateral dose gradients. This article analyses the striated radiation field in the context of the requirements for temporal dosimetric measurements and presents the architecture of a new dosimetry system based on the use of silicon detectors and fast data acquisition electronic interface. The combined system demonstrates micrometer spatial resolution and microsecond real time readout with accurate sensitivity and linearity over five orders of magnitude of input signal. The system will therefore be suitable patient treatment plan verification and may also be expanded for in-vivo beam monitoring for patient safety during the treatment.

  12. Functional characteristics of the growth factor receptor family and some ligands in the oropharyngeal cavity of the Chukar partridge (Alectoris chukar).

    PubMed

    Saruhan, Berna G; Sağsöz, Hakan; Akbalik, Mehmet E; Erdoğan, Serkan

    2015-01-01

    1. The aim of the present study is to describe, immunohistochemically, the expression and cell type localisation of growth factor receptors and some of their ligands in the oropharyngeal organs of the Chukar partridge. 2. The tissue samples from 10 healthy adult partridges were dissected under ether anaesthesia and then embedded in paraffin following routine histological procedures. The immunoreaction for receptors and ligands of the epidermal growth factor receptor (EGFR)/ligand system was localised in the cell membrane, nucleus and cytoplasm of the luminal and glandular epithelial cells, stromal and striated muscle cells, and vascular endothelial and smooth muscle cells. 3. Variations were observed in the avian oropharyngeal organs. The immunostaining for the erbB1/HER1 (human epidermal growth factor receptor 1) and the EGF (epidermal growth factor) and AREG (Amphiregulin) ligands in the luminal epithelial cells was higher than in the glandular epithelial, stromal and striated muscle cells. However, the immunostaining for erbB3/HER3 (human epidermal growth factor receptor 3) and erbB4/HER4 (human epidermal growth factor receptor 4) were similar in the luminal epithelium, stromal and striated muscle cells. 4. Growth factor receptors and some of their ligands were localised in different cell types in the oropharyngeal organs. We suggest that erbB/HERs (human epidermal growth factor receptors) and their ligands play an important role in proliferation, differentiation, growth, survival and migration of the cells. PMID:26569385

  13. Host preference of the arbovirus vector Culex erraticus (Diptera: Culicidae) at Sonso Lake, Cauca Valley Department, Colombia.

    PubMed

    Mendenhall, I H; Tello, S A; Neira, L A; Castillo, L F; Ocampo, C B; Wesson, D M

    2012-09-01

    Culex erraticus (Dyar & Knab) is a competent vector of Eastern equine encephalitis virus and subtype IC Venezuelan equine encephalitis virus, and both St. Louis encephalitis virus and West Nile virus have been isolated from field-collected specimens. Previous bloodmeal analysis studies have shown this species to be a generalist, feeding on a variety of mammals, birds, reptiles, and amphibians. This behavior can bridge arboviral transmission across different vertebrate groups. Our study examined the host preference of Cx. erraticus at Sonso Lake in Colombia. From July to August 2008, blood-engorged mosquitoes were collected from resting boxes, while vertebrate abundance was determined to calculate host preference. Based on mitochondrial DNA analysis of bloodmeals, birds were the predominant hosts (57.6%), followed by mammals (30.8%), and reptiles (6.7%); 9.5% of the bloodmeals were mixed. The most commonly fed upon species were: limpkin, black-crowned night-heron, striated heron, human, and capybara. Forage ratios showed the least bittern, limpkin, Cocoi heron, striated heron, capybara, and black-crowned night heron were preferred hosts across all vertebrates. Of the available avifauna, the least bittern, limpkin, striated heron, Cocoi heron, and black-crowned night heron were preferred, whereas the bare faced ibis, great egret, snowy egret, and cattle egret were under-used. This study shows that while Cx. erraticus is an opportunistic feeder, using diverse vertebrate hosts in the environment, certain avian species are targeted preferentially for bloodmeals. PMID:23025191

  14. Association of myostatin variants with growth traits of Zhikong scallop ( Chlamys farreri)

    NASA Astrophysics Data System (ADS)

    Fu, Qiang; Guo, Huihui; Feng, Liying; Li, Xue; Zhang, Lingling; Wang, Shi; Hu, Xiaoli; Bao, Zhenmin

    2016-02-01

    Scallop is a popular sea food and an important aquaculture shellfish. Identification of genes and genetic variants relating to scallop growth could benefit high-yielding scallop breeding. Myostatin ( MSTN) is a conservative regulator of muscle growth, and has become one of the most important target genes for genetic improvement of the production of farmed animals. In this study, four single nucleotide polymorphisms (SNPs) were identified in the 5' flanking region of MSTN gene ( CfMSTN) in Zhikong scallop ( Chlamys farreri). The association of these SNPs with scallop growth traits, including shell length, shell height, body weight and striated muscle weight was analyzed. The SNP g-1162Gstriated muscle weight. The TT type scallops showed significantly higher trait values than those of GT type, and the GG type individuals exhibited median values. On the contrary, significantly more CfMSTN transcripts were detected in the striated muscle of GT type scallops than in those of TT and GG type ones. Our results suggested that CfMSTN might regulate the scallop muscle growth negatively, and SNP g-1162G

  15. Chloral hydrate alters the organization of the ciliary basal apparatus and cell organelles in sea urchin embryos

    NASA Technical Reports Server (NTRS)

    Chakrabarti, A.; Schatten, H.; Mitchell, K. D.; Crosser, M.; Taylor, M.

    1998-01-01

    The mitotic inhibitor, chloral hydrate, induces ciliary loss in the early embryo phase of Lytechinus pictus. It causes a breakdown of cilia at the junction of the cilium and the basal body known as the basal plate. This leaves the plasma membrane temporarily unsealed. The basal apparatus accessory structures, consisting of the basal body, basal foot, basal foot cap, striated side arm, and striated rootlet, are either misaligned or disintegrated by treatment with chloral hydrate. Furthermore, microtubules which are associated with the basal apparatus are disassembled. Mitochondria accumulate at the base of cilia - underneath the plasma membrane - and show alterations in their structural organization. The accumulation of mitochondria is observed in 40% of all electron micrograph sections while 60% show the areas mostly devoid of mitochondria. The microvilli surrounding a cilium and striated rootlet remain intact in the presence of chloral hydrate. These results suggest that deciliation in early sea urchin embryos by chloral hydrate is caused by combined effects on the ciliary membrane and on microtubules in the cilia. Furthermore, it is suggested that chloral hydrate can serve as a tool to explore the cytoskeletal mechanisms that are involved in cilia motility in the developing sea urchin embryo.

  16. Muscle-Specific Splicing of a Heterologous Exon Mediated by a Single Muscle-Specific Splicing Enhancer from the Cardiac Troponin T Gene

    PubMed Central

    Cooper, Thomas A.

    1998-01-01

    The chicken cardiac troponin T (cTNT) gene contains a single 30-nucleotide alternative exon that is included in embryonic striated muscle and skipped in the adult. Transient-transfection analysis of cTNT minigenes in muscle and fibroblast cell cultures previously identified four muscle-specific splicing enhancers (MSEs) that promote exon inclusion specifically in embryonic striated muscle cultures. Three MSEs located in the intron downstream from the alternative exon were sufficient for muscle-specific exon inclusion. In the present study, the boundaries of these MSEs were defined by scanning mutagenesis, allowing analysis of individual elements in gain-of-function experiments. Concatamers of MSE2 were necessary and sufficient to promote muscle-specific inclusion of a heterologous exon, indicating that it is a target for muscle-specific regulation. Sequences present in MSE2 are also found in MSE4, suggesting that these two MSEs act in a similar manner. MSE3 appears to be different from MSE2 and MSE4 yet is able to functionally replace both of these elements, demonstrating functional redundancy of elements that are likely to bind different factors. MSE2 and MSE4 each contain a novel sequence motif that is found adjacent to a number of alternative exons that undergo regulated splicing in striated muscle, suggesting a common role for this element in muscle-specific regulation. PMID:9671461

  17. Muscle microanatomy and its changes during contraction: the legacy of William Bowman (1816-1892).

    PubMed

    Frixione, Eugenio

    2006-01-01

    Striated muscle fine structure began to be really understood following a comprehensive survey of the matter carried out by William Bowman in the late 1830s. The publications resulting from such a study, the first of which earned for the author a precocious election as Fellow of the Royal Society, are herewith examined in the context of contemporary views on the subject as well as of their subsequent repercussion and current knowledge today. It is shown that not only Bowman succeeded in establishing the true architecture of striated muscle fibres to the extent possible with the most advanced technology available in his day--explaining and eradicating alternative erroneous concepts in the process--but also in correctly describing the basic microstructural changes associated with contraction. In addition, although unrecognized by him or others at the time, his experiments with muscle provided direct evidence for the existence of a selectively permeable cell membrane--in the present meaning of the word--over half a century before its officially accepted discovery. Yet, in spite of these remarkable advances, Bowman arrived at the conclusion that the structure of striated muscle fibres is essentially irrelevant for the mechanism of contraction. Possible reasons behind Bowman's breakthrough accomplishments as a pioneer of modern muscle research, and his failure to understand their significance for muscle physiology, are discussed. PMID:16465470

  18. Titin and myosin, but not desmin, are linked during myofibrillogenesis in postmitotic mononucleated myoblasts.

    PubMed

    Hill, C S; Duran, S; Lin, Z X; Weber, K; Holtzer, H

    1986-12-01

    Monoclonal antibodies specific for the muscle protein titin have been used in conjunction with muscle-specific antibodies against myofibrillar myosin heavy chains (MHCs) and desmin to study myogenesis in cultured cells. Desmin synthesis is initiated in replicating presumptive myoblasts, whereas the synthesis of titin and MHC is initiated simultaneously in their progeny, the postmitotic, mononucleated myoblasts. Both titin and MHC are briefly localized to nonstriated and thereafter to definitively striated myofibrils. At no stage during myofibrillogenesis is either protein observed as part of a sequence of mini-sarcomeres. Titin antibodies bind to the A-I junction, MHC antibodies to the A bands in nascent, maturing, and mature myofibrils. In contrast, desmin remains distributed as longitudinal filaments until well after the definitive myofibrils have aligned laterally. This tight temporal and topographical linkage between titin and myosin is also observed in postmitotic, mononucleated myoblasts and multinucleated myotubes when myofibrillogenesis is perturbed with Colcemid or taxol. Colcemid induces elongating postmitotic mononucleated myoblasts and multinucleated myotubes to round up and form Colcemid myosacs. The myofibrils that emerge in these rounded cells are deployed in convoluted circles. The time required for their nonstriated myofibrils to transform into striated myofibrils is greatly protracted. Furthermore, as Colcemid induces immense desmin intermediate filament cables, the normal spatial relationships between emerging individual myofibrils is distorted. Despite these disturbances at all stages, the characteristic temporal and spatial relationship observed in normal myofibrils between titin and MHC is observed in myofibrils assembling in Colcemid-treated cells. Newly born postmitotic mononucleated myoblasts, or maturing myotubes, reared in taxol acquire a star-shaped configuration and are induced to assemble "pseudo-striated myofibrils." Pseudo-striated

  19. An unusual parotid gland in the tent-building bat, Uroderma bilobatum: possible correlation of interspecific ultrastructural differences with differences in salivary pH and buffering capacity.

    PubMed

    Nagato, T; Tandler, B; Phillips, C J

    1998-10-01

    The tent-building bat, Uroderma bilobatum, is a small, frugivorous phyllostomid bat with a broad neotropical distribution. Generally found in humid forest, this bat lives in small groups that create daytime "roosts" from large leaves of a variety of tropical plants. Fruit eating engenders a variety of ecological and physiological challenges for bats, some of which could require adaptive features in their salivary glands. The parotid salivary glands of Uroderma bilobatum were prepared for transmission electron microscopy by using methods that have become standard for field work. The parotid gland is extremely unusual in structure. Although the secretory endpieces still produce serous granules with a complex substructure, they are modified into quasi striated ducts. Their basal folds, which are extensive, occasionally harbor some vertically oriented mitochondria, imparting a resemblance to striated ducts. Other evidence for the endpiece origin of these parenchymal components is a well-developed system of intercellular canaliculi, structures that never occur in bona fide striated ducts. The long but sparse intercalated ducts consist of two types of cells, each of which elaborates a modest number of secretory granules of differing substructure. Striated ducts are of conventional morphology, except that a few dark cells shaped like wine glasses are present in their walls. The striated duct cells produce no secretory granules, but their apical cytoplasm may contain some small, empty vesicles. Capillaries lie in longitudinal grooves in the base of the duct cells, an arrangement that might enhance electrolyte exchange. Excretory ducts consist of simple cuboidal epithelium composed of cytologically unspecialized cells that sometimes includes a dark cell. It was concluded that salivary glands could have a major role in adapting species to acquire nutrients from marginal sources, such as tropical fruits, which have a low protein and sodium content. The unusual parotid acinar

  20. Ice-flow evolution of the Labrador Sector of the Laurentide Ice Sheet: a review, with new evidence from northern Quebec

    NASA Astrophysics Data System (ADS)

    Veillette, J. J.; Dyke, A. S.; Roy, M.

    1999-07-01

    Outcrops bearing stained, striated facets indicative of north-northeastward moving ice, truncated by unstained, striated facets indicative of various younger flows occur in the Caniapiscau area of north-central Quebec. This is the first report of differential staining of striated facets in the region. We propose that the staining occurred in an ice-free interval of probable interglacial age. This early ice flow probably occurred during ice retreat toward the Quebec highlands. Ice flow and glacial transport data from the southern Hudson Bay and James Bay basins indicate that the next major regional ice flow was toward the northwest and resulted from the expansion of an Early Wisconsinan glacier in the Quebec highlands. The northern part of this flow was diverted northwestward through Hudson Bay, and the southern part southwestward across James Bay, following a progressive counterclockwise rotation of flow. A zone of intersection (ZI) of two major glacier bedform systems, often referred to as the horseshoe-shaped Labrador Ice Divide, represents the head of a large northward convergent ice-flow system that extended to Ungava Bay and beyond. The Ungava flow propagated southward and captured the head of the opposing flow from an outflow centre located east of Caniaspiscau reservoir. We propose that this capture event correlates with the Gold Cove Advance in Ungava Bay and on Baffin Island at about 9900 14C yr BP. It is the largest advance of Quebec-Labrador ice yet proposed for the region. This correlation is based on the relative ice-flow chronology, accommodation of glacial lakes Naskaupi and McLean in the deglaciation sequence, the constraints placed on Last Glacial Maximum (LGM) ice configuration by the postglacial uplift pattern and events in the deep-sea record. Therefore, the Ungava ice-flow pattern is not a relict pre-Wisconsinan glacial landscape as recently proposed.

  1. Substrate & Cell Compliance Effects on Cell Spreading and Differentiation

    NASA Astrophysics Data System (ADS)

    Discher, Dennis; Sheehan, Maureen; Engler, Adam

    2004-03-01

    The stiffness of the substrate that a cell adheres to is emerging as a critically important physical factor in the response of many cell types. The effects are seen with cells on gels as well as cells on cells - highlighting implications for organism development. The basis for the effects lies in the fact that cells literally 'feel' their substrate. Like other anchorage dependent cells, muscle cells feel their substrate and are found in our studies to spread more and organize their cytoskeleton and focal adhesions much more so on rigid glass and stiff substrates than on soft gels. Such spreading is not necessarily physiological or conducive to biological function. Collagen density certainly factors into cell on gel adhesive spreading, with minimal spreading on very low collagen and a weak maximum in cell spreading on intermediate collagen densities. Bell-shaped curves are readily modeled to highlight the coupling between ligand density and substrate stiffness. Most surprising, however, spreading on soft gels is found to be almost independent of adhesive ligand density: even with high collagen densities, the minimal spreading of cells cannot be over-ridden. Remarkably, muscle cells show the strongest tendency to differentiate and striate their acto-myosin on gels that have a stiffness similar to relaxed muscle. Cells gown on top of other cells also show a very strong tendency to striate, even if the underlying cells do not striate; elasticity measurements appear to unify all of the effects. The implications for organismal development as well as cell biological studies can be very important.

  2. Involvement of Superoxide Dismutase in Spore Coat Assembly in Bacillus subtilis

    PubMed Central

    Henriques, Adriano O.; Melsen, Lawrence R.; Moran, Charles P.

    1998-01-01

    Endospores of Bacillus subtilis are enclosed in a proteinaceous coat which can be differentiated into a thick, striated outer layer and a thinner, lamellar inner layer. We found that the N-terminal sequence of a 25-kDa protein present in a preparation of spore coat proteins matched that of the Mn-dependent superoxide dismutase (SOD) encoded by the sodA locus. sodA is transcribed throughout the growth and sporulation of a wild-type strain and is responsible for the SOD activity detected in total cell extracts prepared from B. subtilis. Disruption of the sodA locus produced a mutant that lacked any detectable SOD activity during vegetative growth and sporulation. The sodA mutant was not impaired in the ability to form heat- or lysozyme-resistant spores. However, examination of the coat layers of sodA mutant spores revealed increased extractability of the tyrosine-rich outer coat protein CotG. We showed that this condition was not accompanied by augmented transcription of the cotG gene in sporulating cells of the sodA mutant. We conclude that SodA is required for the assembly of CotG into the insoluble matrix of the spore and suggest that CotG is covalently cross-linked into the insoluble matrix by an oxidative reaction dependent on SodA. Ultrastructural analysis revealed that the inner coat formed by a sodA mutant was incomplete. Moreover, the outer coat lacked the characteristic striated appearance of wild-type spores, a pattern that was accentuated in a cotG mutant. These observations suggest that the SodA-dependent formation of the insoluble matrix containing CotG is largely responsible for the striated appearance of this coat layer. PMID:9573176

  3. Topography and homogeneity of monkey V1 studied through subdurally recorded pattern-evoked potentials.

    PubMed

    Dagnelie, G; Spekreijse, H; van Dijk, B

    1989-12-01

    Using small checkerboard stimulus fields, we have recorded visually evoked potentials (VEPs) in an alert rhesus monkey from an array of 35 electrodes chronically implanted between dura and arachnoid to study mass neuronal activity in striate and peristriate visual cortex. Although the principal purpose of this work was to study in detail cortical mapping in this particular animal for future intracortical recordings, we report here the usefulness of our approach for the non-invasive study of cortical processing, in particular of cortical magnification and receptive-field properties over the central 6 degrees of the visual field. The striate and extrastriate components in the pattern onset VEP both have a double negative-going waveform, with N-P-N peak latencies of 75-100-135 ms and 90-115-160 ms, respectively, for small element sizes and moderate contrasts; latencies may be 5 ms shorter for large element sizes and high contrast. We found little activity at electrode locations over visual areas beyond V2. The waveforms and timing permit some careful speculation concerning intracortical processing and VEP generation. The complex logarithmic form of the retinotopical projection provides a satisfactory model for our data, if a value of 1-1.2 degrees is used for the offset parameter a. Our data suggest that the most abundant receptive-field size in foveal striate cortex has a center diameter of 12'. This size remains constant up to 2 degrees eccentricity, and increases only slowly up to 4 degrees. The smallest receptive-field sizes seem to be independent of eccentricity throughout the central 4 degrees of V1, with a value of 4-8', in agreement with single-cell data reported by Dow et al. (1981) and Van Essen et al. (1984). PMID:2487121

  4. Tectorial Membrane Material Properties in TectaY1870C/+ Heterozygous Mice

    PubMed Central

    Masaki, Kinuko; Ghaffari, Roozbeh; Gu, Jianwen Wendy; Richardson, Guy P.; Freeman, Dennis M.; Aranyosi, A.J.

    2010-01-01

    The solid component of the tectorial membrane (TM) is a porous matrix made up of the radial collagen fibers and the striated sheet matrix. The striated sheet matrix is believed to contribute to shear impedance in both the radial and longitudinal directions, but the molecular mechanisms involved have not been determined. A missense mutation in Tecta, a gene that encodes for the α-tectorin protein in the striated sheet matrix, causes a 60-dB threshold shift in mice with relatively little reduction in outer hair cell amplification. Here, we show that this threshold shift is coupled to changes in shear impedance, response to osmotic pressure, and concentration of fixed charge of the TM. In TectaY1870C/+ mice, the tectorin content of the TM was reduced, as was the content of glycoconjugates reacting with the lectin wheat germ agglutinin. Charge measurements showed a decrease in fixed charge concentration from −6.4±1.4 mmol/L in wild-types to −2.1±0.7 mmol/L in TectaY1870C/+ TMs. TMs from TectaY1870C/+ mice showed little volume change in response to osmotic pressure compared to those of wild-type mice. The magnitude of both radial and longitudinal TM shear impedance was reduced by 10±1.6 dB in TectaY1870C/+ mice. However, the phase of shear impedance was unchanged. These changes are consistent with an increase in the porosity of the TM and a corresponding decrease of the solid fraction. Mechanisms by which these changes can affect the coupling between outer and inner hair cells are discussed. PMID:21081075

  5. Morphological analysis of the urethral muscle of the male pig with relevance to urinary continence and micturition.

    PubMed

    Ragionieri, Luisa; Ravanetti, Francesca; Gazza, Ferdinando; Botti, Maddalena; Ivanovska, Ana; Cacchioli, Antonio

    2016-03-01

    To investigate whether the pig could be considered a suitable model to study lower urinary tract function and dysfunction, the pelvic urethra of 24 slaughtered male pigs were collected, and the associated muscles were macroscopically, histologically and histochemically analyzed. In cross-sections of the urethra, a muscular complex composed of an inner layer of smooth muscle and an outer layer of striated muscle that are not separated by fascial planes was observed. A tunica muscularis, composed of differently oriented smooth muscle bundles, is only evident in the proximal part of the pelvic urethra while, in the remaining part, it contributes to form the prostatic fibromuscular stroma. The striated urethral muscle surrounds the pelvic urethra in a horseshoe-like configuration with a dorsal longitudinal raphe, extending from the bladder neck to the central tendon of perineum. Proximally to the bladder, it is constituted of slow-twitch and fast-twitch myofibers of very small diameter, and embedded in an abundant collagen and elastic fiber net. Moving caudally it is gradually encircled and then completely substituted by larger and compact myofibers, principally presenting circular orientation and fast-twitch histochemical characteristics. So, like in humans, the cranial tract of the muscular system surrounding the pelvic urethra is principally composed of smooth musculature. The striated component cranially may have a role in blocking retrograde ejaculation, while the middle and caudal tracts may facilitate urine and semen flow, and seem especially concerned with the rapid and forceful urethral closure during active continence. Some differences in the morphology and structure between pigs and humans seem due to the different morphology of the 'secondary' sexual organs that develop from the urethral wall and to the different effect of gravity on the mechanics of the urinary system in quadruped and bipedal mammals. PMID:26573248

  6. Differential effects of temperature and glucose on glycogenolytic enzymes in tissues of rainbow trout (Oncorhynchus mykiss).

    PubMed

    Bolinger, Mark T; Rodnick, Kenneth J

    2014-05-01

    The pathways and regulatory mechanisms of glycogenolysis remain relatively unexplored in non-mammalian vertebrates, especially poikilotherms. We studied the temperature sensitivity and inhibition of glycogenolytic enzymes in liver, ventricle, and white muscle of rainbow trout acclimated to 14 °C. Glycogen phosphorylase (GP) and acid α-glucosidase (GAA) activities were measured in homogenates of tissues at physiological temperatures (4, 14, and 24 °C), and in the presence of allosteric inhibitor, glucose. Higher GP versus GAA activity in all three tissues suggested a predominance of phosphorolytic glycogenolysis over the lysosomal glucosidic pathway. GP activities at 14 °C were ~2-fold higher in the ventricle and white muscle versus the liver and selectively increased by AMP in striated muscle. Conversely, the activities of GAA and lysosomal marker acid phosphatase were 8- to 10-fold higher in the liver compared with the ventricle and white muscle. Thermal sensitivity (Q10) was increased for GP in all tissues below 14 °C and decreased in striated muscle in the absence of AMP above 14 °C. GAA had lower Q10 values than GP below 14 °C, and, unlike GP, Q10s for GAA were not different between tissues or affected by temperature. Both GP (in the absence of AMP) and GAA were inhibited by glucose in a dose-dependent manner, with the lowest IC50 values observed in the white muscle (1.4 and 6.3 mM, respectively). In conclusion, despite comparatively low kinetic potential, lysosomal GAA might facilitate glycogenolysis at colder body temperatures in striated muscle and intracellular glucose could limit phosphorolytic and glucosidic glycogenolysis in multiple tissues of the rainbow trout. PMID:24704523

  7. Structural Phenotyping of Stem Cell-Derived Cardiomyocytes

    PubMed Central

    Pasqualini, Francesco Silvio; Sheehy, Sean Paul; Agarwal, Ashutosh; Aratyn-Schaus, Yvonne; Parker, Kevin Kit

    2015-01-01

    Summary Structural phenotyping based on classical image feature detection has been adopted to elucidate the molecular mechanisms behind genetically or pharmacologically induced changes in cell morphology. Here, we developed a set of 11 metrics to capture the increasing sarcomere organization that occurs intracellularly during striated muscle cell development. To test our metrics, we analyzed the localization of the contractile protein α-actinin in a variety of primary and stem-cell derived cardiomyocytes. Further, we combined these metrics with data mining algorithms to unbiasedly score the phenotypic maturity of human-induced pluripotent stem cell-derived cardiomyocytes. PMID:25733020

  8. A new structural interpretation relating NW Libya to the Hun Graben, western Sirt Basin based on a new paleostress inversion

    NASA Astrophysics Data System (ADS)

    Abdunaser, K. M.; McCaffrey, K. J. W.

    2015-12-01

    The present study is based on fault-slip data (striated fault planes with known sense of slip) measured in outcrops in two structural domains located along the Hun Graben, western Sirt Basin (150 fault-slip data) and the Jifarah Basin and Nafusah Uplift, northwest Libya (200 fault-slip data). Pre-existing field data collected in two previous studies were reprocessed using standard inversion methods in MyFaultTM(v. 1.03) stereonet software, produced by Pangaea Scientific Ltd.

  9. A new geographic and host record for infectious pancreatic necrosis

    USGS Publications Warehouse

    Parisot, T.J.; Yasutake, W.T.; Bressler, V.

    1963-01-01

    The occurrence of infectious pancreatic necrosis in rainbow trout (Salmo gairdneri), brook trout (Salvelinus fontinalis), and cutthroat trout (Salmo clarki) has been experimentally authenticated for the first time in the western United States. The cutthroat trout represents a new host. Brook trout fin tissue culture inoculated with bacteria-free filtrate from the diseased fish tissue showed marked degenerative changes after 24 hours. Chinook salmon (Oncorhynchus tshawytscha), kokanee (O. nerka), and silver salmon (O. kisutch) were not susceptible to the virus when inoculated. Histologically, extensive pancreatic necrosis was observed in the original and experimental materials, but striated muscle hyalinization was detected only in the original material.

  10. Beryllium-10 dating of the duration and retreat of the last pinedale glacial sequence.

    PubMed

    Gosse, J C; Klein, J; Lawn, B; Middleton, R; Evenson, E B

    1995-06-01

    Accurate terrestrial glacial chronologies are needed for comparison with the marine record to establish the dynamics of global climate change during transitions from glacial to interglacial regimes. Cosmogenic beryllium-10 measurements in the Wind River Range indicate that the last glacial maximum (marine oxygen isotope stage 2) was achieved there by 21,700 +/- 700 beryllium-10 years and lasted 5900 years. Ages of a sequence of recessional moraines and striated bedrock surfaces show that the initial deglaciation was rapid and that the entire glacial system retreated 33 kilometers to the cirque basin by 12,100 +/- 500 beryllium-10 years. PMID:17778979

  11. Beryllium-10 dating of the duration and retreat of the last pinedale glacial sequence

    SciTech Connect

    Gosse, J.C. |; Klein, J.; Evenson, E.B.

    1995-06-02

    Accurate terrestrial glacial chronologies are needed for comparison with the marine record to establish the dynamics of global climate change during transitions from glacial to interglacial regimes. Cosmogenic beryllium-10 measurements in the Wind River Range indicate that the last glacial maximum (marine oxygen isotope stage 2) was achieved there by 21,700 {+-} 700 beryllium-10 years and lasted 5900 years. Ages of a sequence of recessional moraines and striated bedrock surfaces show that the initial deglaciation was rapid and that the entire glacial system retreated 33 kilometers to the cirque basin by 12,100 {+-} 500 beryllium-10 years.

  12. Visual pathways and psychophysical channels in the primate

    PubMed Central

    Lee, Barry B

    2011-01-01

    The main cell systems of the retina that provide input to the striate cortex are now well described, although certain aspects of their anatomy and physiology remain contentious. Under simple stimulus conditions and in a threshold context psychophysical performance can often be assigned to one or other of these systems, and an identification of psychophysical channels with afferent pathways is justifiable. However, results from psychophysical studies using more complex stimulus conditions are more difficult to relate to ‘front end’ channels, and it is more difficult to separate the physiological contributions of afferent pathways from those of cortical mechanisms, in particular the separation of dorsal and ventral streams. PMID:20724364

  13. The length–tension curve in muscle depends on lattice spacing

    PubMed Central

    Williams, C. David; Salcedo, Mary K.; Irving, Thomas C.; Regnier, Michael; Daniel, Thomas L.

    2013-01-01

    Classic interpretations of the striated muscle length–tension curve focus on how force varies with overlap of thin (actin) and thick (myosin) filaments. New models of sarcomere geometry and experiments with skinned synchronous insect flight muscle suggest that changes in the radial distance between the actin and myosin filaments, the filament lattice spacing, are responsible for between 20% and 50% of the change in force seen between sarcomere lengths of 1.4 and 3.4 µm. Thus, lattice spacing is a significant force regulator, increasing the slope of muscle's force–length dependence. PMID:23843386

  14. Imaging of Retrochiasmal and Higher Cortical Visual Disorders.

    PubMed

    Tantiwongkosi, Bundhit; Salamon, Noriko

    2015-08-01

    Retrochiasmal visual pathways include optic tracts, lateral geniculate nuclei, optic radiations, and striate cortex (V1). Homonymous hemianopsia and field defect variants with relatively normal visual acuity suggest that the lesions involve retrochiasmal pathways. From V1, visual input is projected to higher visual association areas that are responsible for perception of objects, faces, colors, and orientation. Visual association areas are classified into ventral and dorsal pathways. Damage to the ventral stream results in visual object agnosia, prosopagnosia, and achromatopsia. Balint syndrome, visual inattention, and pure alexia are examples of dorsal stream disorders. Posterior cortical atrophy can involve ventral and dorsal streams, often preceding dementia. PMID:26208417

  15. Visual pathways and psychophysical channels in the primate.

    PubMed

    Lee, Barry B

    2011-01-01

    The main cell systems of the retina that provide input to the striate cortex are now well described, although certain aspects of their anatomy and physiology remain contentious. Under simple stimulus conditions and in a threshold context psychophysical performance can often be assigned to one or other of these systems, and an identification of psychophysical channels with afferent pathways is justifiable. However, results from psychophysical studies using more complex stimulus conditions are more difficult to relate to 'front end' channels, and it is more difficult to separate the physiological contributions of afferent pathways from those of cortical mechanisms, in particular the separation of dorsal and ventral streams. PMID:20724364

  16. The live lattices become visible in coherent synchrotron X-rays

    NASA Astrophysics Data System (ADS)

    Kohn, V.; Rau, C.; Sergienko, P. M.; Snigireva, I.; Snigirev, A.; Vazina, A.

    2005-05-01

    We demonstrate a great potential of the method of phase contrast imaging for a study of muscles and animal organism in normal and pathological states. The method is applied to image biological tissues that have the unique feature of structure-translation symmetry of 0.1-10 μm periodicity. The cross-striated muscle is the most interesting example of such objects. The experiment was done using high-brilliant coherent X-rays, delivered by synchrotron radiation source of third generation (ESRF, Grenoble), and high-resolution 2D-detector.

  17. Tropomyosin exons as models for alternative splicing.

    PubMed

    Gooding, Clare; Smith, Christopher W J

    2008-01-01

    Three of the four mammalian tropomyosin (Tm) genes are alternatively spliced, most commonly by mutually exclusive selection from pairs of internal or 3' end exons. Alternative splicing events in the TPM1, 2 and 3 genes have been analysed experimentally in various levels ofdetail. In particular, mutually exclusive exon pairs in the betaTm (TPM2) and alphaTm (TPM1) genes are among the most intensively studied models for striated and smooth muscle specific alternative splicing, respectively. Analysis of these model systems has provided important insights into general mechanisms and strategies of splicing regulation. PMID:19209811

  18. Mitsugumin 56 (hedgehog acyltransferase-like) is a sarcoplasmic reticulum-resident protein essential for postnatal muscle maturation.

    PubMed

    Van, Bo; Nishi, Miyuki; Komazaki, Shinji; Ichimura, Atsuhiko; Kakizawa, Sho; Nakanaga, Keita; Aoki, Junken; Park, Ki-Ho; Ma, Jianjie; Ueyama, Tomomi; Ogata, Takehiro; Maruyama, Naoki; Takeshima, Hiroshi

    2015-04-28

    Mitsugumin 56 (MG56), also known as the membrane-bound O-acyl-transferase family member hedgehog acyltransferase-like, was identified as a new sarcoplasmic reticulum component in striated muscle. Mg56-knockout mice grew normally for a week after birth, but shortly thereafter exhibited a suckling defect and died under starvation conditions. In the knockout skeletal muscle, regular contractile features were largely preserved, but sarcoplasmic reticulum elements swelled and further developed enormous vacuoles. In parallel, the unfolded protein response was severely activated in the knockout muscle, and presumably disrupted muscle development leading to the suckling failure. Therefore, MG56 seems essential for postnatal skeletal muscle maturation. PMID:25841338

  19. Tropomyosin flexural rigidity and single ca(2+) regulatory unit dynamics: implications for cooperative regulation of cardiac muscle contraction and cardiomyocyte hypertrophy.

    PubMed

    Loong, Campion K P; Badr, Myriam A; Chase, P Bryant

    2012-01-01

    Striated muscle contraction is regulated by dynamic and cooperative interactions among Ca(2+), troponin, and tropomyosin on the thin filament. While Ca(2+) regulation has been extensively studied, little is known about the dynamics of individual regulatory units and structural changes of individual tropomyosin molecules in relation to their mechanical properties, and how these factors are altered by cardiomyopathy mutations in the Ca(2+) regulatory proteins. In this hypothesis paper, we explore how various experimental and analytical approaches could broaden our understanding of the cooperative regulation of cardiac contraction in health and disease. PMID:22493584

  20. Fine structure of the submandibular salivary gland of the venomous short-tailed shrew, Blarina brevicauda Say (Insectivora: Soricidae).

    PubMed

    Carson, K A; Rose, R K

    1993-01-01

    Adult male short-tailed shrews, Blarina brevicauda, (Insectivora: Soricidae) were trapped in Virginia and Pennsylvania, anesthetized, and perfused via the left ventricle of the heart with fixative. The submandibular glands were dissected free and prepared for transmission electron microscopy. The lobular, compound tubuloacinar glands had secretory endpieces consisting of seromucous acini and serous tubules connected to intercalated ducts, granular ducts, striated ducts, and excretory ducts. The general cytology of the submandibular gland of Blarina shared morphological characters with individuals in several other mammalian orders and yet differed in many ways from another Insectivore, the European hedgehog, Erinaceus europaeus. PMID:8398545

  1. ROS and RNS signaling in skeletal muscle: critical signals and therapeutic targets

    PubMed Central

    Michaelson, Luke P; Iler, Colleen; Ward, Christopher W

    2016-01-01

    The health of skeletal muscle is promoted by optimal nutrition and activity/exercise through the activation of molecular signaling pathways. Reactive oxygen species (ROS) or reactive nitrogen species (RNS) have been shown to modulate numerous biochemical processes including glucose uptake, gene expression, calcium signaling and contractility. In pathological conditions, ROS/RNS signaling excess or dysfunction contributes to contractile dysfunction and myopathy in skeletal muscle. Here we provide a brief review of ROS/RNS chemistry and discuss concepts of ROS/RNS signaling and its role in physiological and pathophysiological processes within striated muscle. PMID:24894146

  2. Catalogue of the mite family Tydeidae (Acari: Prostigmata) with the world key to the species.

    PubMed

    Silva, Guilherme Liberato Da; Metzelthin, Maicon Henrique; Silva, Onilda Santos Da; Ferla, Noeli Juarez

    2016-01-01

    Members of the Tydeidae are cosmopolitan, soft-bodied, striated or reticulated mites that are reported to be mainly phytophages, mycophages, pollenophages, insect parasites or scavengers. This catalogue includes 328 species belonging to 30 genera, and their distributions and type habitat. Until now, Brachytydeus comprises the largest number of species with 200, followed by Tydeus, with 50 species, and Pretydeus and Pseudolorryia, with 12 species each. An updated list of the Tydeidae (Acari: Prostigmata), a world key to the species and data on the zoogeographical distribution of the species are presented. PMID:27395702

  3. Solution NMR assignment of the heavy chain complex of the human cardiac myosin regulatory light chain.

    PubMed

    Rostkova, Elena; Gautel, Mathias; Pfuhl, Mark

    2015-04-01

    The regulatory light chain (RLC) of striated and cardiac muscle myosin plays a complex role in muscle function and regulation. Together with the essential light chain it provides stability to the lever arm, which is essential for force generation. Furthermore, phosphorylation and interaction with myosin binding protein C (MyBP-C) suggest an additional role in the regulation of muscle contraction. The former is of particular importance in the heart, where RLC phosphorylation appears to be correlated to the wringing motion of heart contraction. To address these questions and because of a lack of mammalian RLC structures, we initiated an NMR study of the human cardiac regulatory myosin light chain. PMID:24414277

  4. Geology and geochemistry of the Macheng Algoma-type banded iron-formation, North China Craton: Constraints on mineralization events and genesis of high-grade iron ores

    NASA Astrophysics Data System (ADS)

    Wu, Huaying; Niu, Xianglong; Zhang, Lianchang; Pirajno, Franco; Luo, Huabao; Qin, Feng; Cui, Minli; Wang, Changle; Qi, Min

    2015-12-01

    The Macheng iron deposit is located in the eastern Hebei province of the North China Craton (NCC). It is hosted in Neoarchean metamorphic rocks of Baimiaozi formation in the Dantazi Group, consisting of biotite-leptynite, plagioclase-gneiss, plagioclase-amphibolite, migmatite, migmatitic granite and quartz schist. Geochemical analyses of the host biotite leptynite and plagioclase amphibolites show that their protoliths are both volcanics, inferred to be trachytic basalt and basaltic andesite, respectively. Based on the geochemical signature of the host rocks, together with geology of the iron deposit, it is inferred that the Macheng BIF is an Algoma-type iron exhalative formation, formed in an arc-related basin in the Neoarchean. Post-Archean Australian Shale (PAAS)-normalized rare earth elements (REEs) plus yttrium (Y) concentrations of different BIF ores with gneissic, striated and banded structure in the Macheng deposit, show similar patterns with depletions in light rare earth elements (LREEs) and middle rare earth elements (MREEs) relative to heavy rare earth elements (HREEs) and with apparently positive La, Y and Eu anomalies. Y/Ho ratios of the gneissic, striated and banded BIF ores vary from 37 to 56. These geochemical features of the BIF ores reveal their affinity with the sea water and the presence of a high-temperature hydrothermal component, indicating that both the seawater and high temperature hydrothermal fluids derived from alteration of oceanic basalts and komatiites may contribute to formation of the Macheng BIF. Geological, mineralogical and geochemical studies of the Macheng deposit recognized two kinds of high-grade iron ores. One is massive oxidized high-grade ore (Fe2O3T = 74.37-86.20 wt.%), mainly consisting of hematite with some magnetite, which shows geochemical characteristics of the gneissic, striated and banded BIF ores. The other type is magnetite high-grade ore, also massive and consisting of magnetite, with distinct characteristics

  5. The tension mounts: Stress fibers as force-generating mechanotransducers

    PubMed Central

    Wittchen, Erika S.

    2013-01-01

    Stress fibers (SFs) are often the most prominent cytoskeletal structures in cells growing in tissue culture. Composed of actin filaments, myosin II, and many other proteins, SFs are force-generating and tension-bearing structures that respond to the surrounding physical environment. New work is shedding light on the mechanosensitive properties of SFs, including that these structures can respond to mechanical tension by rapid reinforcement and that there are mechanisms to repair strain-induced damage. Although SFs are superficially similar in organization to the sarcomeres of striated muscle, there are intriguing differences in their organization and behavior, indicating that much still needs to be learned about these structures. PMID:23295347

  6. Skeletal muscle disorders associated with inflammatory bowel diseases: occurrence of myositis in a patient with ulcerative colitis and Hashimoto's thyroiditis--case report and review of the literature.

    PubMed

    Paoluzi, Omero Alessandro; Crispino, Pietro; Rivera, Margherita; Iacopini, Federico; Palladini, Dino; Consolazio, Adriana; Paoluzi, Paolo

    2006-07-01

    Ulcerative colitis (UC) and Crohn's disease are inflammatory bowel diseases often associated with extra-intestinal manifestations. Of these, neutrophilic dermatoses and arthropathies are the more frequently observed, while the occurrence of striated muscle disorders, namely, myositis, has been very rarely diagnosed in these kinds of patients. The coexistence of immuno-mediated diseases in patients with inflammatory bowel diseases and myositis suggests a common aetiopathogenetic mechanism underlying these conditions. The present report refers to a rare case of a 51-year-old female with UC and Hashimoto's thyroiditis who developed myositis. PMID:16205931

  7. Requirements for contractility in disordered cytoskeletal bundles

    NASA Astrophysics Data System (ADS)

    Lenz, Martin; Gardel, Margaret L.; Dinner, Aaron R.

    2012-03-01

    Actomyosin contractility is essential for biological force generation, and is well understood in highly organized structures such as striated muscle. Additionally, actomyosin bundles devoid of this organization are known to contract both in vivo and in vitro, which cannot be described by standard muscle models. To narrow down the search for possible contraction mechanisms in these systems, we investigate their microscopic symmetries. We show that contractile behavior requires non-identical motors that generate large-enough forces to probe the nonlinear elastic behavior of F-actin. This suggests a role for filament buckling in the contraction of these bundles, consistent with recent experimental results on reconstituted actomyosin bundles.

  8. The length-tension curve in muscle depends on lattice spacing.

    PubMed

    Williams, C David; Salcedo, Mary K; Irving, Thomas C; Regnier, Michael; Daniel, Thomas L

    2013-09-01

    Classic interpretations of the striated muscle length-tension curve focus on how force varies with overlap of thin (actin) and thick (myosin) filaments. New models of sarcomere geometry and experiments with skinned synchronous insect flight muscle suggest that changes in the radial distance between the actin and myosin filaments, the filament lattice spacing, are responsible for between 20% and 50% of the change in force seen between sarcomere lengths of 1.4 and 3.4 µm. Thus, lattice spacing is a significant force regulator, increasing the slope of muscle's force-length dependence. PMID:23843386

  9. Note: Effective measurement of retained I(c) in evaluating electromechanical properties of high temperature superconductor tapes by the voltage tap clipping technique.

    PubMed

    Dedicatoria, Marlon J; Bautista, Zhierwinjay; Shin, Hyung-Seop; Sim, Kideok

    2015-08-01

    In this note, the effectiveness of voltage tap clipping technique was assessed in evaluating the electromechanical properties of high temperature superconductor (HTS) tapes in the aspect of practical device applications. In the four-probe transport I(c) measurement, instead of directly soldering the voltage lead wires onto the HTS samples, they were tapped to the sample by either just clipping or soldering them to the clips. This technique facilitated the simultaneous and repeated retained I(c) measurement test for multiple samples. Finally, the critical double bending diameter of HTS tapes and the electrical properties of jointed and striated coated conductor tapes could be easily determined. PMID:26329241

  10. Spontaneous sarcomere dynamics

    NASA Astrophysics Data System (ADS)

    Günther, Stefan; Kruse, Karsten

    2010-12-01

    Sarcomeres are the basic force generating units of striated muscles and consist of an interdigitating arrangement of actin and myosin filaments. While muscle contraction is usually triggered by neural signals, which eventually set myosin motors into motion, isolated sarcomeres can oscillate spontaneously between a contracted and a relaxed state. We analyze a model for sarcomere dynamics, which is based on a force-dependent detachment rate of myosin from actin. Our numerical bifurcation analysis of the spontaneous sarcomere dynamics reveals notably Hopf bifurcations, canard explosions, and gluing bifurcations. We discuss possible implications for experiments.

  11. The length-tension curve in muscle depends on lattice spacing

    SciTech Connect

    Williams, C. D.; Salcedo, M. K.; Irving, T. C.; Regnier, M.; Daniel, T. L.

    2013-07-10

    Classic interpretations of the striated muscle length–tension curve focus on how force varies with overlap of thin (actin) and thick (myosin) filaments. New models of sarcomere geometry and experiments with skinned synchronous insect flight muscle suggest that changes in the radial distance between the actin and myosin filaments, the filament lattice spacing, are responsible for between 20% and 50% of the change in force seen between sarcomere lengths of 1.4 and 3.4 µm. Thus, lattice spacing is a significant force regulator, increasing the slope of muscle's force–length dependence.

  12. Hyperpigmentation and atrophy in folds as cutaneous manifestation in a case of mitochondrial myopathy.

    PubMed

    Campuzano-García, Andrés Eduardo; Rodríguez-Arámbula, Adriana; Torres-Alvarez, Bertha; Castanedo-Cázares, Juan Pablo

    2015-05-01

    Mitochondrial myopathies are inborn metabolism defect diseases manifested by symptoms reflecting failure of the final step in the mitochondrial respiratory chain. Clinical expression of these conditions can vary widely, but typically includes organ systems with a high energy demand, such as striated muscle, myocardium, and nervous and liver tissues. In contrast, cutaneous manifestations are rare and are non-specific, most commonly presenting as pigmentation disorders. In this case report, we present a case of Alpers syndrome accompanied by hyperpigmentation and atrophy in skin folds. PMID:26295861

  13. Background issues for defensive interceptors

    SciTech Connect

    Canavan, G.H.

    1991-03-01

    Mean nuclear backgrounds are large, but are arguably amenable to frame-to-frame subtraction. Striated backgrounds on the sensors for defensive interceptors could, however, cause clutter leak-through, which could make detection and track difficult. Nominal motions and backgrounds give signal to clutter ratios too low to be useful. Clutter leakage due to line-of-sight drift can be reduced by stabilizing the line of sight around the background clutter itself. Current interceptors have detector arrays large enough for operation independent of nuclear backgrounds in their fields of view. 6 refs., 2 figs.

  14. Trichodorus elefjohnsoni n. sp. (Nemata: Trichodoridae) from Undisturbed Appalachian Forest

    PubMed Central

    Bernard, E. C.

    1992-01-01

    A new species of Trichodoridae, Trichodorus elefjohnsoni, is described from undisturbed regions of Great Smoky Mountains National Park, United States. It resembles T. orientalis De Waele &Hashim, 1984, T. persicus De Waele &Sturhan, 1987, and T. taylori De Waele, Mancini, Roca, ' Lamberti, 1982 in arrangement of ventromedian cervical papillae and posterior preanal supplements, but differs by combinations of the following characteristics: body length 516-731 μm; spicule length 33-50 μm, spicules densely striated, constricted medially; vaginal sclerotizations ovate; one pair of lateral body pores near vulva. PMID:19283205

  15. Audiovisual Association Learning in the Absence of Primary Visual Cortex

    PubMed Central

    Seirafi, Mehrdad; De Weerd, Peter; Pegna, Alan J.; de Gelder, Beatrice

    2016-01-01

    Learning audiovisual associations is mediated by the primary cortical areas; however, recent animal studies suggest that such learning can take place even in the absence of the primary visual cortex. Other studies have demonstrated the involvement of extra-geniculate pathways and especially the superior colliculus (SC) in audiovisual association learning. Here, we investigated such learning in a rare human patient with complete loss of the bilateral striate cortex. We carried out an implicit audiovisual association learning task with two different colors of red and purple (the latter color known to minimally activate the extra-genicular pathway). Interestingly, the patient learned the association between an auditory cue and a visual stimulus only when the unseen visual stimulus was red, but not when it was purple. The current study presents the first evidence showing the possibility of audiovisual association learning in humans with lesioned striate cortex. Furthermore, in line with animal studies, it supports an important role for the SC in audiovisual associative learning. PMID:26778999

  16. Background and stimulus-induced patterns of high metabolic activity in the visual cortex (area 17) of the squirrel and macaque monkey

    SciTech Connect

    Humphrey, A.L.; Hendrickson, A.E.

    1983-02-01

    The authors have used 2-deoxy-D-(/sup 14/C)glucose (2-DG) autoradiography and cytochrome oxidase histochemistry to examine background and stimulus-induced patterns of metabolic activity in monkey striate cortex. In squirrel monkeys (Saimiri sciureus) that binocularly or monocularly viewed diffuse white light or binocularly viewed bars of many orientations and spatial frequencies, 2-DG consumption was not uniform across the cortex but consisted of regularly spaced radial zones of high uptake. The cytochrome oxidase stain in these animals also revealed patches of high metabolism which coincided with the 2-DG patches. Squirrel monkeys binocularly viewing vertical stripes showed parallel bands of increased 2-DG uptake in the cortex, while the cytochrome label in these animals remained patchy. In macaque (Macaca nemestrina) monkeys, binocular stimulation with many orientations and spatial frequencies produced radial zones of high 2-DG uptake. When viewed tangentially, these zones formed a dots-in-rows pattern with a spacing of 350 X 500 microns; cytochrome oxidase staining produced an identical pattern. Macaca differed from Saimiri in that monocular stimulation labeled alternate rows. These results indicate that there are radial zones of high background metabolism across squirrel and macaque monkey striate cortex. In Saimiri these zones do not appear to be related to an eye dominance system, while in Macaca they do. The presence of these zones of high metabolism may complicate the interpretation of 2-DG autoradiographs that result from specific visual stimuli.

  17. The dislocation of medical dominance: making space for interprofessional care.

    PubMed

    Bleakley, Alan

    2013-09-01

    The historical transition of modern medicine from an autonomous profession to a team-based interprofessional practice can be described in terms of space rather than time, with "place" as the unit of analysis. Imagining modern medicine spatially was instigated by Foucault, who described medical dominance as a territorializing of both individual body spaces and public spaces--the former through the diagnostic medical gaze, the latter in a gaze of health surveillance. However, much has happened since Foucault's (1963) analysis. The diagnostic gaze has been dispersed to develop a collaborative gaze including patients and healthcare professionals; political interests have appropriated the public health gaze; and the medical profession is subject to democratic processes of accountability. Medicine has lost its territorial imperative as new "liquid" and "nomadic" work practices emerge, making space for interprofessional care. Such dislocation of medical dominance and its multiple relocations are poorly theorised. Deleuze and Guattari distinguish between "striated" and "smooth" spaces. Striated space is associated with hierarchies and boundaries, where smooth space includes boundary crossing and democratic collaboration. Smooth or liminal spaces in hospitals, such as corridors, can paradoxically act as catalysts for collaboration or assembly democracy, affording opportunities for improvised interprofessional encounters. Such encounters can act as an antidote to planned protocols or imperatives for interprofessional collaboration. PMID:23930686

  18. Leukotrienes as mediators in ischemia-reperfusion injury in a microcirculation model in the hamster.

    PubMed Central

    Lehr, H A; Guhlmann, A; Nolte, D; Keppler, D; Messmer, K

    1991-01-01

    Leukotriene (LT)B4 promotes leukocyte chemotaxis and adhesion to the endothelium of postcapillary venules. The cysteinyl leukotrienes, LTC4, LTD4, and LTE4, elicit macromolecular leakage from this vessel segment. Both leukocyte adhesion to the endothelium and macromolecular leakage from postcapillary venules hallmark the microcirculatory failure after ischemia-reperfusion, suggesting a role of leukotrienes as mediators of ischemia-reperfusion injury. Using the dorsal skinfold chamber model for intravital fluorescence microscopy of the microcirculation in striated muscle in awake hamsters and sequential RP-HPLC and RIA for leukotrienes, we demonstrate in this study that (a) the leukotrienes (LT)B4 and LTD4 elicit leukocyte/endothelium interaction and macromolecular leakage from postcapillary venules, respectively, that (b) leukotrienes accumulate in the tissue after ischemia and reperfusion, and that (c) selective inhibition of leukotriene biosynthesis (by MK-886) prevents both postischemic leukotriene accumulation and the microcirculatory changes after ischemia-reperfusion, while blocking of LTD4/E4 receptors (by MK-571) inhibits postischemic macromolecular leakage. These results demonstrate a key role of leukotrienes in ischemia-reperfusion injury in striated muscle in vivo. Images PMID:1645749

  19. Titin stiffness modifies the force-generating region of muscle sarcomeres.

    PubMed

    Li, Yong; Lang, Patrick; Linke, Wolfgang A

    2016-01-01

    The contractile units of striated muscle, the sarcomeres, comprise the thick (myosin) and thin (actin) filaments mediating active contraction and the titin filaments determining "passive" elasticity. We hypothesized that titin may be more active in muscle contraction by directly modulating thick-filament properties. We used single-myofibril mechanical measurements and atomic force microscopy of individual sarcomeres to quantify the effects of sarcomere strain and titin spring length on both the inter-filament lattice spacing and the lateral stiffness of the actin-myosin overlap zone (A-band). We found that strain reduced the lattice spacing similarly in sarcomeres with stiff (rabbit psoas) or compliant titin (rabbit diaphragm), but increased A-band lateral stiffness much more in psoas than in diaphragm. The strain-induced alterations in A-band stiffness that occur independently of lattice spacing effects may be due to titin stiffness-sensing by A-band proteins. This mechanosensitivity could play a role in the physiologically important phenomenon of length-dependent activation of striated muscle. PMID:27079135

  20. Decoding the direction of imagined visual motion using 7 T ultra-high field fMRI

    PubMed Central

    Emmerling, Thomas C.; Zimmermann, Jan; Sorger, Bettina; Frost, Martin A.; Goebel, Rainer

    2016-01-01

    There is a long-standing debate about the neurocognitive implementation of mental imagery. One form of mental imagery is the imagery of visual motion, which is of interest due to its naturalistic and dynamic character. However, so far only the mere occurrence rather than the specific content of motion imagery was shown to be detectable. In the current study, the application of multi-voxel pattern analysis to high-resolution functional data of 12 subjects acquired with ultra-high field 7 T functional magnetic resonance imaging allowed us to show that imagery of visual motion can indeed activate the earliest levels of the visual hierarchy, but the extent thereof varies highly between subjects. Our approach enabled classification not only of complex imagery, but also of its actual contents, in that the direction of imagined motion out of four options was successfully identified in two thirds of the subjects and with accuracies of up to 91.3% in individual subjects. A searchlight analysis confirmed the local origin of decodable information in striate and extra-striate cortex. These high-accuracy findings not only shed new light on a central question in vision science on the constituents of mental imagery, but also show for the first time that the specific sub-categorical content of visual motion imagery is reliably decodable from brain imaging data on a single-subject level. PMID:26481673

  1. Behavioural and electrophysiological chromatic and achromatic contrast sensitivity in an achromatopsic patient.

    PubMed Central

    Heywood, C A; Nicholas, J J; Cowey, A

    1996-01-01

    OBJECTIVES--In cases of incomplete achromatopsia it is unclear whether residual visual function is mediated by intact striate cortex or results from incomplete lesions to extrastriate cortical visual areas. A patient with complete cerebral achromatopsia was tested to establish the nature of his residual vision and to determine the integrity of striate cortex function. METHODS--Behavioural contrast sensitivity, using the method of adjustment, and averaged visually evoked cortical potentials were measured to sinusoidally modulated chromatic and achromatic gratings in an achromatopsic patient and a normal observer. Eye movements were measured in the patient using a Skalar infrared monitoring system. RESULTS--The patient's chromatic contrast sensitivity was normal, indicating that despite his dense colour blindness his occipital cortex still processed information about spatial variations in hue. His sensitivity to achromatic gratings was depressed particularly at high spatial frequencies, possibly because of his jerk nystagmus. These behavioural results were reinforced by the nature of visually evoked responses to chromatic and achromatic gratings, in which total colour blindness coexisted with an almost normal cortical potential to isoluminant chromatic gratings. CONCLUSIONS--The results show that information about chromatic contrast is present in some cortical areas, and coded in a colour-opponent fashion, in the absence of any perceptual experience of colour. PMID:8648330

  2. Melting and cataclastic features in shatter cones in basalt from the Vista Alegre impact structure, Brazil

    NASA Astrophysics Data System (ADS)

    Pittarello, Lidia; Nestola, Fabrizio; Viti, Cecilia; Crósta, Alvaro Penteado; Koeberl, Christian

    2015-07-01

    Shatter cones are one of the most widely recognized pieces of evidence for meteorite impact events on Earth, but the process responsible for their formation is still debated. Evidence of melting on shatter cone surfaces has been rarely reported in the literature from terrestrial impact craters but has been recently observed in impact experiments. Although several models for shatter cones formation have been proposed, so far, no one can explain all the observed features. Shatter cones' from the Vista Alegre impact structure, Brazil, formed in fine-grained basalt of the Jurassic-Cretaceous Serra Geral Formation (Paraná large igneous province). A continuous quenched melt film, consisting of a crystalline phase, mica, and amorphous material, decorates the striated surface. Ultracataclasites, containing subrounded pyroxene clasts in an ultrafine-grained matrix, occur subparallel to the striated surface. Several techniques were applied to characterize the crystalline phase in the melt, including Raman spectroscopy and transmission electron microscopy. Results are not consistent with any known mineral, but they do suggest a possible rare or new type of clinopyroxene. This peculiar evidence of melting and cataclasis in relation with shatter cone surfaces is interpreted as the result of tensile fracturing at the tip of a fast propagating shock-induced rupture, which led to the formation of shatter cones at the tail of the shock front, likely during the early stage of the impact events.

  3. Oesophageal and sternohyal muscle fibres are novel Pax3-dependent migratory somite derivatives essential for ingestion.

    PubMed

    Minchin, James E N; Williams, Victoria C; Hinits, Yaniv; Low, Siewhui; Tandon, Panna; Fan, Chen-Ming; Rawls, John F; Hughes, Simon M

    2013-07-01

    Striated muscles that enable mouth opening and swallowing during feeding are essential for efficient energy acquisition, and are likely to have played a fundamental role in the success of early jawed vertebrates. The developmental origins and genetic requirements of these muscles are uncertain. Here, we determine by indelible lineage tracing in mouse that fibres of sternohyoid muscle (SHM), which is essential for mouth opening during feeding, and oesophageal striated muscle (OSM), which is crucial for voluntary swallowing, arise from Pax3-expressing somite cells. In vivo Kaede lineage tracing in zebrafish reveals the migratory route of cells from the anteriormost somites to OSM and SHM destinations. Expression of pax3b, a zebrafish duplicate of Pax3, is restricted to the hypaxial region of anterior somites that generate migratory muscle precursors (MMPs), suggesting that Pax3b plays a role in generating OSM and SHM. Indeed, loss of pax3b function led to defective MMP migration and OSM formation, disorganised SHM differentiation, and inefficient ingestion and swallowing of microspheres. Together, our data demonstrate Pax3-expressing somite cells as a source of OSM and SHM fibres, and highlight a conserved role of Pax3 genes in the genesis of these feeding muscles of vertebrates. PMID:23760954

  4. Investigation of the electrophysiological correlates of negative BOLD response during intermittent photic stimulation: An EEG-fMRI study.

    PubMed

    Maggioni, Eleonora; Zucca, Claudio; Reni, Gianluigi; Cerutti, Sergio; Triulzi, Fabio M; Bianchi, Anna M; Arrigoni, Filippo

    2016-06-01

    Although the occurrence of concomitant positive BOLD responses (PBRs) and negative BOLD responses (NBRs) to visual stimuli is increasingly investigated in neuroscience, it still lacks a definite explanation. Multimodal imaging represents a powerful tool to study the determinants of negative BOLD responses: the integration of functional Magnetic Resonance Imaging (fMRI) and electroencephalographic (EEG) recordings is especially useful, since it can give information on the neurovascular coupling underlying this complex phenomenon. In the present study, the brain response to intermittent photic stimulation (IPS) was investigated in a group of healthy subjects using simultaneous EEG-fMRI, with the main objective to study the electrophysiological mechanisms associated with the intense NBRs elicited by IPS in extra-striate visual cortex. The EEG analysis showed that IPS induced a desynchronization of the basal rhythm, followed by the instauration of a novel rhythm driven by the visual stimulation. The most interesting results emerged from the EEG-informed fMRI analysis, which suggested a relationship between the neuronal rhythms at 10 and 12 Hz and the BOLD dynamics in extra-striate visual cortex. These findings support the hypothesis that NBRs to visual stimuli may be neuronal in origin rather than reflecting pure vascular phenomena. Hum Brain Mapp 37:2247-2262, 2016. © 2016 Wiley Periodicals, Inc. PMID:26987932

  5. Depletion of lamina-associated polypeptide 1 from cardiomyocytes causes cardiac dysfunction in mice

    PubMed Central

    Shin, Ji-Yeon; Le Dour, Caroline; Sera, Fusako; Iwata, Shinichi; Homma, Shunichi; Joseph, Leroy C; Morrow, John P; Dauer, William T; Worman, Howard J

    2014-01-01

    We previously showed that striated muscle-selective depletion of lamina-associated polypeptide 1 (LAP1), an integral inner nuclear membrane protein, leads to profound muscular dystrophy with premature death in mice. As LAP1 is also depleted in hearts of these mice, we examined their cardiac phenotype. Striated muscle-selective LAP1 knockout mice display ventricular systolic dysfunction with abnormal induction of genes encoding cardiomyopathy related proteins. To eliminate possible confounding effects due to skeletal muscle pathology, we generated a new mouse line in which LAP1 is deleted in a cardiomyocyte-selective manner. These mice had no skeletal muscle pathology and appeared overtly normal at 20 weeks of age. However, cardiac echocardiography revealed that they developed left ventricular systolic dysfunction and cardiac gene expression analysis revealed abnormal induction of cardiomyopathy-related genes. Our results demonstrate that LAP1 expression in cardiomyocytes is required for normal left ventricular function, consistent with a report of cardiomyopathy in a human subject with mutation in the gene encoding LAP1. PMID:24859316

  6. The sarcoplasmic reticulum: then and now.

    PubMed

    Somlyo, Andrew P; Somlyo, Avril V

    2002-01-01

    Structural and functional studies indicate the important role of the sarcoplasmic reticulum (SR) in excitation-contraction coupling in smooth and striated muscles, as well as a similar Ca2+ signalling function of the endoplasmic reticulum (ER) in non-muscle cells. Electron probe analysis directly established the SR/ER of smooth muscle as a sink and source of Ca2+, while immunoelectron and immunofluorescence microscopy showed both inositol-1,4,5-trisphosphate (InsP3) and ryanodine receptors localized to its membranes. Structural relationships, some yet to have fully determined functions, occur between the mitochondria and the SR, and the junctional SR and plasma membrane. Ca2+ is released by stimuli that generate InsP3 indicating the primary role of InsP3 receptors in Ca2+-release in smooth, although not in striated, muscle. Pathological mitochondrial Ca2+ uptake occurs at high [Ca2+]i similarly in both muscle and non-muscle cells. Based on newer evidence, earlier experimental results obtained with fluorescent Ca2+ indicators and related to phasic and tonic components of contraction can now be reinterpreted. Electron energy loss spectroscopy for high-resolution Ca2+ imaging and flash photolysis of caged agonists for exploration of the rapid kinetics of Ca2+ release from the SR are currently being explored. PMID:12164313

  7. Regulation of muscle contraction by Drebrin-like protein 1 probed by atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Garces, Renata; Butkevich, Eugenia; Platen, Mitja; Schmidt, Christoph F.; Biophysics Team

    Sarcomeres are the fundamental contractile units of striated muscle cells. They are composed of a variety of structural and regulatory proteins functioning in a precisely orchestrated fashion to enable coordinated force generation in striated muscles. Recently, we have identified a C. elegans drebrin-like protein 1 (DBN-1) as a novel sarcomere component, which stabilizes actin filaments during muscle contraction. To further characterize the function of DBN-1 in muscle cells, we generated a new dbn-1 loss-of-function allele. Absence of DBN-1 resulted in a unique worm movement phenotype, characterized by hyper-bending. It is not clear yet if DBN-1 acts to enhance or reduce the capacity for contraction. We present here an experimental mechanical study on C. elegans muscle mechanics. We measured the stiffness of the worm by indenting living C. eleganswith a micron-sized sphere adhered to the cantilever of an atomic force microscope (AFM). Modeling the worm as a pressurized elastic shell allows us to monitor the axial tension in the muscle through the measured stiffness. We compared responses of wild-type and mutant C. elegans in which DBN-1 is not expressed..

  8. Chemotherapy-Induced Weakness and Fatigue in Skeletal Muscle: The Role of Oxidative Stress

    PubMed Central

    St. Clair, Daret K.

    2011-01-01

    Abstract Significance Fatigue is one of the most common symptoms of cancer and its treatment, manifested in the clinic through weakness and exercise intolerance. These side effects not only compromise patient's quality of life (QOL), but also diminish physical activity, resulting in limited treatment and increased morbidity. Recent Advances Oxidative stress, mediated by cancer or chemotherapeutic agents, is an underlying mechanism of the drug-induced toxicity. Nontargeted tissues, such as striated muscle, are severely affected by oxidative stress during chemotherapy, leading to toxicity and dysfunction. Critical Issues These findings highlight the importance of investigating clinically applicable interventions to alleviate the debilitating side effects. This article discusses the clinically available chemotherapy drugs that cause fatigue and oxidative stress in cancer patients, with an in-depth focus on the anthracycline doxorubicin. Doxorubicin, an effective anticancer drug, is a primary example of how chemotherapeutic agents disrupt striated muscle function through oxidative stress. Future Directions Further research investigating antioxidants could provide relief for cancer patients from debilitating muscle weakness, leading to improved quality of life. Antioxid. Redox Signal. 15, 2543–2563. PMID:21457105

  9. RBM24 is a major regulator of muscle-specific alternative splicing.

    PubMed

    Yang, Jiwen; Hung, Lee-Hsueh; Licht, Thomas; Kostin, Sawa; Looso, Mario; Khrameeva, Ekaterina; Bindereif, Albrecht; Schneider, Andre; Braun, Thomas

    2014-10-13

    Cell-type-specific splicing generates numerous alternatively spliced transcripts playing important roles for organ development and homeostasis, but only a few tissue-specific splicing factors have been identified. We found that RBM24 governs a large number of muscle-specific splicing events that are critically involved in cardiac and skeletal muscle development and disease. Targeted inactivation of RBM24 in mice disrupted cardiac development and impaired sarcomerogenesis in striated muscles. In vitro splicing assays revealed that recombinant RBM24 is sufficient to promote muscle-specific exon inclusion in nuclear extracts of nonmuscle cells. Furthermore, we demonstrate that binding of RBM24 to an intronic splicing enhancer (ISE) is essential and sufficient to overcome repression of exon inclusion by an exonic splicing silencer (ESS) containing PTB and hnRNP A1/A2 binding sites. Introduction of ESS and ISE converted a constitutive exon into an RMB24-dependent alternative exon. We reason that RBM24 is a major regulator of alternative splicing in striated muscles. PMID:25313962

  10. Mechano-regulated Tenascin-C orchestrates muscle repair

    PubMed Central

    Flück, Martin; Mund, Sonja I.; Schittny, Johannes C.; Klossner, Stephan; Durieux, Anne-Cécile; Giraud, Marie-Noëlle

    2008-01-01

    Tenascin-C (TNC) is a mechano-regulated, morphogenic, extracellular matrix protein that is associated with tissue remodeling. The physiological role of TNC remains unclear because transgenic mice engineered for a TNC deficiency, via a defect in TNC secretion, show no major pathologies. We hypothesized that TNC-deficient mice would demonstrate defects in the repair of damaged leg muscles, which would be of functional significance because this tissue is subjected to frequent cycles of mechanical damage and regeneration. TNC-deficient mice demonstrated a blunted expression of the large TNC isoform and a selective atrophy of fast-muscle fibers associated with a defective, fast myogenic expression response to a damaging mechanical challenge. Transcript profiling mapped a set of de-adhesion, angiogenesis, and wound healing regulators as TNC expression targets in striated muscle. Expression of these regulators correlated with the residual expression of a damage-related 200-kDa protein, which resembled the small TNC isoform. Somatic knockin of TNC in fast-muscle fibers confirmed the activation of a complex expression program of interstitial and slow myofiber repair by myofiber-derived TNC. The results presented here show that a TNC-orchestrated molecular pathway integrates muscle repair into the load-dependent control of the striated muscle phenotype. PMID:18757758

  11. Half-Sarcomere Dynamics in Myofibrils during Activation and Relaxation Studied by Tracking Fluorescent Markers

    PubMed Central

    Telley, Ivo A.; Denoth, Jachen; Stüssi, Edgar; Pfitzer, Gabriele; Stehle, Robert

    2006-01-01

    To study the dynamics of individual half-sarcomeres in striated muscle contraction, myofibrils prepared from rabbit psoas muscle and left ventricles of guinea pig were immunostained with two conjugated antibody complexes consisting of a primary antibody against either α-actinin or myomesin and a secondary fluorescently labeled Fab-fragment. We simultaneously measured force kinetics and determined the positions of the Z-line and M-band signals by fluorescence video microscopy and sophisticated computer vision (tracking) algorithms. Upon calcium activation, sarcomeres and half-sarcomeres shortened nonuniformly. Shortening occurred first rapidly and exponentially during the force rise and then slowly during the force plateau. In psoas myofibrils, time-resolved displacements of the A-band in sarcomeres were observed, i.e., the two halves of individual sarcomeres behaved nonuniformly. Nonuniformity in length changes between the two halves of sarcomeres was comparable to that between two adjacent half-sarcomeres of neighboring sarcomeres. Sequential lengthening of half-sarcomeres was observed in cardiac myofibrils during the rapid phase of force relaxation. The independent dynamics of the halves in a sarcomere reveals the half-sarcomere as the functional unit rather than the structural unit, the sarcomere. The technique will facilitate the study of filament sliding within individual half-sarcomeres and the mechanics of intersegmental chemomechanical coupling in multisegmental striated muscles. PMID:16239326

  12. Wolbachia Occurrence in Planthopper (Hemiptera: Delphacidae) Vectors of Cereal Viruses in Argentina.

    PubMed

    Mattio, M F; Argüello Caro, E B; Rodriguero, M S; Dumón, A D; Alemandri, V M; Truol, G

    2015-08-01

    Maize (Zea mays L.) and wheat (Triticum aestivum L.) are the most important cereal crops for the Argentinean economy and are affected by several diseases. Different planthopper species transmit causal agents of some of those diseases, including Mal de Río Cuarto virus, barley yellow striate mosaic virus, and the recently proposed maize yellow striate virus. Many planthopper species are sap feeders and therefore are expected to host bacteria providing essential nutrients lacking in the diet. Previous studies have evidenced that some of these bacterial symbionts are involved in the virus transmission. Wolbachia is a group of obligate intracellular bacteria infecting numerous arthropod species and causing reproductive alterations in their hosts. These bacteria have been detected in planthopper species, considered rice pests in various regions of the world. To date, Wolbachia infection status of planthopper species of Argentina is unknown. Amplification by PCR and sequencing of 16S rDNA, wsp- and ftsZ-specific genes demonstrated Wolbachia infection in Caenodelphax teapae (Fowler), Delphacodes kuscheli Fennah, Pyrophagus tigrinus Remes Lenicov & Varela, Tagosodes orizicolus (Muir), and Toya propinqua (Fieber). This is the first report of Wolbachia in delphacid vectors of viruses affecting maize and wheat. An understanding of the bacterial diversity harbored by these insect vectors could lead to new options for future management of diseases of economically important crops in a developing country. PMID:26470291

  13. Heart and Skeletal Muscle Are Targets of Dengue Virus Infection

    PubMed Central

    Salgado, Doris Martha; Eltit, José Miguel; Mansfield, Keith; Panqueba, César; Castro, Dolly; Vega, Martha Rocio; Xhaja, Kris; Schmidt, Diane; Martin, Katherine J.; Allen, Paul D.; Rodriguez, Jairo Antonio; Dinsmore, Jonathan H.; López, José Rafael; Bosch, Irene

    2010-01-01

    Background Dengue fever is one of the most significant re-emerging tropical diseases, despite our expanding knowledge of the disease, viral tropism is still not known to target heart tissues or muscle. Methods A prospective pediatric clinical cohort of 102 dengue hemorrhagic fever patients from Colombia, South America, was followed for 1 year. Clinical diagnosis of myocarditis was routinely performed. Electrocardiograph and echocardiograph analysis were performed to confirm those cases. Immunohistochemistry for detection of dengue virus and inflammatory markers was performed on autopsied heart tissue. In vitro studies of human striated skeletal fibers (myotubes) infected with dengue virus were used as a model for myocyte infection. Measurements of intracellular Ca2+ concentration as well as immunodetection of dengue virus and inflammation markers in infected myotubes were performed. Results Eleven children with dengue hemorrhagic fever presented with symptoms of myocarditis. Widespread viral infection of the heart, myocardial endothelium, and cardiomyocytes, accompanied by inflammation was observed in 1 fatal case. Immunofluorescence confocal microscopy showed that myotubes were infected by dengue virus and had increased expression of the inflammatory genes and protein IP-10. The infected myotubes also had increases in intracellular Ca2+ concentration. Conclusions Vigorous infection of heart tissues in vivo and striated skeletal cells in vitro are demonstrated. Derangements of Ca2+ storage in the infected cells may directly contribute to the presentation of myocarditis in pediatric patients. PMID:20032806

  14. Enteric neuromuscular junctions: comparison of ultrastructural features in different phylogenetic groups.

    PubMed

    Halasy, K; Benedeczky, I; Fekete, E; Tóth, L; Gábriel, R

    1988-04-01

    The enteric neuromuscular junctions of snail (Helix pomatia), locust (Locusta migratoria migratorioides), cockroach (Periplaneta americana), carp (Cyprinus carpio) and tench (Tinca tinca) were studied by means of different light and electron microscopic methods. The nitroblue tetrazolium staining revealed that the myenteric plexuses of the above species are composed of nerve cells, a network of varicose nerves and nerve bundles. Instead of highly organized ganglia, single neurons or small groups of 2-4 cells are characteristic of the invertebrates and fish studied. Catecholaminergic fluorescence induced by glyoxylic acid was detected in the muscular layer of the entire alimentary tract in snail and the hindgut of tench. Fluorescent nerves and perikarya were frequent in the snail gut, while only nerves and no perikarya were found in tench. A close contact between enteric muscles and nerves is the most common form of enteric neuromuscular junction in both the smooth (i.e. the molluscan and fish gut) and the striated (i.e. the insect gut) musculature. The striated musculature (i.e. the insect gut, the oesophagus of carp, and the oesophagus, stomach and the midgut of tench) also receives a synaptic input. Cytochemical evidence is provided of the cholinergic character of fish motor endplates. The ultrastructural appearance and vesicle population of certain nerve terminals suggest a universal role of aminergic and peptidergic control in gut motility. PMID:3393275

  15. Objective analysis of toolmarks in forensics

    SciTech Connect

    Grieve, Taylor N.

    2013-01-01

    Since the 1993 court case of Daubert v. Merrell Dow Pharmaceuticals, Inc. the subjective nature of toolmark comparison has been questioned by attorneys and law enforcement agencies alike. This has led to an increased drive to establish objective comparison techniques with known error rates, much like those that DNA analysis is able to provide. This push has created research in which the 3-D surface profile of two different marks are characterized and the marks’ cross-sections are run through a comparative statistical algorithm to acquire a value that is intended to indicate the likelihood of a match between the marks. The aforementioned algorithm has been developed and extensively tested through comparison of evenly striated marks made by screwdrivers. However, this algorithm has yet to be applied to quasi-striated marks such as those made by the shear edge of slip-joint pliers. The results of this algorithm’s application to the surface of copper wire will be presented. Objective mark comparison also extends to comparison of toolmarks made by firearms. In an effort to create objective comparisons, microstamping of firing pins and breech faces has been introduced. This process involves placing unique alphanumeric identifiers surrounded by a radial code on the surface of firing pins, which transfer to the cartridge’s primer upon firing. Three different guns equipped with microstamped firing pins were used to fire 3000 cartridges. These cartridges are evaluated based on the clarity of their alphanumeric transfers and the clarity of the radial code surrounding the alphanumerics.

  16. Collicular vision guides nonconscious behavior.

    PubMed

    Tamietto, Marco; Cauda, Franco; Corazzini, Luca Latini; Savazzi, Silvia; Marzi, Carlo A; Goebel, Rainer; Weiskrantz, Lawrence; de Gelder, Beatrice

    2010-05-01

    Following destruction or deafferentation of primary visual cortex (area V1, striate cortex), clinical blindness ensues, but residual visual functions may, nevertheless, persist without perceptual consciousness (a condition termed blindsight). The study of patients with such lesions thus offers a unique opportunity to investigate what visual capacities are mediated by the extrastriate pathways that bypass V1. Here we provide evidence for a crucial role of the collicular-extrastriate pathway in nonconscious visuomotor integration by showing that, in the absence of V1, the superior colliculus (SC) is essential to translate visual signals that cannot be consciously perceived into motor outputs. We found that a gray stimulus presented in the blind field of a patient with unilateral V1 loss, although not consciously seen, can influence his behavioral and pupillary responses to consciously perceived stimuli in the intact field (implicit bilateral summation). Notably, this effect was accompanied by selective activations in the SC and in occipito-temporal extrastriate areas. However, when instead of gray stimuli we presented purple stimuli, which predominantly draw on S-cones and are thus invisible to the SC, any evidence of implicit visuomotor integration disappeared and activations in the SC dropped significantly. The present findings show that the SC acts as an interface between sensory and motor processing in the human brain, thereby providing a contribution to visually guided behavior that may remain functionally and anatomically segregated from the geniculo-striate pathway and entirely outside conscious visual experience. PMID:19320547

  17. Localization of tetra(m-hydroxyphenyl)chlorin (Foscan) in human healthy tissues and squamous cell carcinomas of the upper aero-digestive tract, the esophagus and the bronchi: a fluorescence microscopy study.

    PubMed

    Andrejevic Blant, S; Grosjean, P; Ballini, J P; Wagnières, G; van den Bergh, H; Fontolliet, C; Monnier, P

    2001-08-15

    To date, little is known about precise time-dependent distribution and histological localization of tetra(m-hydroxyphenyl)chlorin (mTHPC) in human healthy tissues and squamous cell malignancies in the upper aero-digestive tract. A fluorescence microscopy study was performed on 50 healthy tissue biopsies and on 13 tumors (graded from Tis to T1 SCC) from 30 patients. Tissue samples were taken between 4 h and 11 days following injection of 0.15 mg/kg mTHPC. A fairly comparable distribution pattern in various tissues was observed over time in different patients. Vascular localization of mTHPC fluorescence predominates at a short delay, whereas the dye is essentially located in the tumoral and healthy mucosa after longer delays. A much lower uptake and retention of mTHPC fluorescence was noted in striated muscle and cartilage as compared to neoplastic lesions. No significant selectivity was found between healthy and tumoral mucosa. The obtained data are important to confirm drug-light interval that have been selected for effective PDT for early SCC malignancies while minimizing the risks of over- or under-treatment. The low fluorescence level in striated muscle provides the opportunity to develop interstitial PDT as a treatment modality for invasive SCC of unfavorable locations in the oral cavity or pharynx, such as the base of the tongue. PMID:11485842

  18. Disparity processing in primary visual cortex.

    PubMed

    Henriksen, Sid; Tanabe, Seiji; Cumming, Bruce

    2016-06-19

    The first step in binocular stereopsis is to match features on the left retina with the correct features on the right retina, discarding 'false' matches. The physiological processing of these signals starts in the primary visual cortex, where the binocular energy model has been a powerful framework for understanding the underlying computation. For this reason, it is often used when thinking about how binocular matching might be performed beyond striate cortex. But this step depends critically on the accuracy of the model, and real V1 neurons show several properties that suggest they may be less sensitive to false matches than the energy model predicts. Several recent studies provide empirical support for an extended version of the energy model, in which the same principles are used, but the responses of single neurons are described as the sum of several subunits, each of which follows the principles of the energy model. These studies have significantly improved our understanding of the role played by striate cortex in the stereo correspondence problem.This article is part of the themed issue 'Vision in our three-dimensional world'. PMID:27269598

  19. Drug Insight: biological effects of botulinum toxin A in the lower urinary tract

    PubMed Central

    Chancellor, Michael B; Fowler, Clare J; Apostolidis, Apostolos; de Groat, William C; Smith, Christopher P; Somogyi, George T; Aoki, K Roger

    2011-01-01

    SUMMARY Botulinum toxins can effectively and selectively disrupt and modulate neurotransmission in striated muscle. Recently, urologists have become interested in the use of these toxins in patients with detrusor overactivity and other urological disorders. In both striated and smooth muscle, botulinum toxin A (BTX-A) is internalized by presynaptic neurons after binding to an extracellular receptor (ganglioside and presumably synaptic vesicle protein 2C). In the neuronal cytosol, BTX-A disrupts fusion of the acetylcholine-containing vesicle with the neuronal wall by cleaving the SNAP-25 protein in the synaptic fusion complex. The net effect is selective paralysis of the low-grade contractions of the unstable detrusor, while still allowing high-grade contraction that initiates micturition. Additionally, BTX-A seems to have effects on afferent nerve activity by modulating the release of ATP in the urothelium, blocking the release of substance P, calcitonin gene-related peptide and glutamate from afferent nerves, and reducing levels of nerve growth factor. These effects on sensory feedback loops might not only help to explain the mechanism of BTX-A in relieving symptoms of overactive bladder, but also suggest a potential role for BTX-A in the relief of hyperalgesia associated with lower urinary tract disorders. PMID:18461049

  20. Neuromuscular dysfunction in nonbacterial prostatitis.

    PubMed

    Hellstrom, W J; Schmidt, R A; Lue, T F; Tanagho, E A

    1987-08-01

    Although chronic nonbacterial prostatitis is common, the condition remains poorly understood and refractory to treatment. Another approach, i.e., a urodynamic explanation, seems warranted. The underlying cause of the symptoms may be an inappropriate spasm of of the distal urethra/external sphincteric unit, leading to increased pressure in the prostatic urethra with a resultant reflux of urine into the prostatic ducts. The presence of urine (sterile or infected) could induce ductal and periductal inflammation, which could further aggravate spasm of the involved pelvic musculature, exacerbating the voiding dysfunction. We present 3 patients in whom this sequence of events was documented radiographically and urodynamically. Consequently, treatment involved modulation of the dysfunction of the distal urethra/external sphincteric unit: (1) reeducation by reassurance and biofeedback was the initial line of therapy; (2) pharmacologic manipulation using alpha-blockers (to affect smooth and striated muscle irritability) and striated muscle relaxants was next tried; (3) finally, in unremitting symptoms, we used selective sacral-root electro-stimulation, successfully fatiguing the involved muscles and relieving the voiding dysfunction. PMID:3497475

  1. Ballistic transfection of mammalian cells in vivo

    SciTech Connect

    Kolesnikov, V.A.; Zelenin, A.V.; Zelenina, I.A.

    1995-11-01

    The method of ballistic transfection initially proposed for genetic transformation of plants was used for animal cells in vitro and in situ. The method consists in bombarding the transfected cells with microparticles of heavy metals carrying foreign DNA. Penetrating the cell nucleus, the microparticles transport the introduced gene. Successful genetic transformation of the cultured mouse cells and fish embryos was realized, and this allowed the study of mammalian cells in situ. The performed studies allowed us to demonstrate expression of the reporter genes of chloramphenicol acetyltransferase, galactosidase, and neomycin phosphotransferase in the mouse liver, mammary gland and kidney explants, in the liver and cross-striated muscle of mouse and rat in situ, and in developing mouse embryos at the stages of two-cell embryo, morula, and blastocyst. All these genes were introduced by ballistic transfection. In the liver and cross-striated muscle the transgene activity was detected within two to three months after transfection. Thus, the ballistic introduction of the foreign genes in the cells in situ was demonstrated, and this opens possibilities for the use of this method in gene therapy. Methodical aspects of the bombarding and transfection are considered in detail, and the published data on transfection and genetic transformation of mammalian cells are discussed. 41 refs., 13 figs., 1 tab.

  2. Enhanced efficacy of an AAV vector encoding chimeric, highly secreted acid alpha-glucosidase in glycogen storage disease type II.

    PubMed

    Sun, Baodong; Zhang, Haoyue; Benjamin, Daniel K; Brown, Talmage; Bird, Andrew; Young, Sarah P; McVie-Wylie, Alison; Chen, Y-T; Koeberl, Dwight D

    2006-12-01

    Glycogen storage disease type II (GSD-II; Pompe disease; MIM 232300) is an inherited muscular dystrophy caused by deficiency in the activity of the lysosomal enzyme acid alpha-glucosidase (GAA). We hypothesized that chimeric GAA containing an alternative signal peptide could increase the secretion of GAA from transduced cells and enhance the receptor-mediated uptake of GAA in striated muscle. The relative secretion of chimeric GAA from transfected 293 cells increased up to 26-fold. Receptor-mediated uptake of secreted, chimeric GAA corrected cultured GSD-II patient cells. High-level hGAA was sustained in the plasma of GSD-II mice for 24 weeks following administration of an AAV2/8 vector encoding chimeric GAA; furthermore, GAA activity was increased and glycogen content was significantly reduced in striated muscle and in the brain. Administration of only 1 x 10(10) vector particles increased GAA activity in the heart and diaphragm for >18 weeks, whereas 3 x 10(10) vector particles increased GAA activity and reduced glycogen content in the heart, diaphragm, and quadriceps. Furthermore, an AAV2/2 vector encoding chimeric GAA produced secreted hGAA for >12 weeks in the majority of treated GSD-II mice. Thus, chimeric, highly secreted GAA enhanced the efficacy of AAV vector-mediated gene therapy in GSD-II mice. PMID:16987711

  3. Enhanced Efficacy of an AAV Vector Encoding Chimeric, Highly-Secreted Acid α-glucosidase in Glycogen Storage Disease Type II

    PubMed Central

    Sun, Baodong; Zhang, Haoyue; Benjamin, Daniel K.; Brown, Talmage; Bird, Andrew; Young, Sarah P.; McVie-Wylie, Alison; Chen, Y-T; Koeberl, Dwight D.

    2009-01-01

    Glycogen storage disease type II (GSD-II; Pompe disease; MIM 232300) is an inherited muscular dystrophy caused by deficiency in the activity of the lysosomal enzyme acid α-glucosidase (GAA). We hypothesized that chimeric GAA containing an alternative signal peptide could increase the secretion of GAA from transduced cells and enhance the receptor-mediated uptake of GAA in striated muscle. The relative secretion of chimeric GAA from transfected 293 cells increased up to 26-fold. Receptor-mediated uptake of secreted, chimeric GAA corrected cultured GSD-II patient cells. High-level hGAA was sustained in the plasma of GSD-II mice for 24 weeks following administration of an AAV2/8 vector encoding chimeric GAA; furthermore, GAA activity was increased and glycogen content was significantly reduced in striated muscle and in the brain. Administration of only 1×1010 vector particles increased GAA activity in the heart and diaphragm for >18 weeks, whereas 3×1010 vector particles increased GAA activity and reduced glycogen content in the heart, diaphragm, and quadriceps. Furthermore, an AAV2/2 vector encoding chimeric GAA produced secreted hGAA for >12 weeks in the majority of treated GSD-II mice. Thus, chimeric, highly secreted GAA enhanced the efficacy of AAV vector-mediated gene therapy in GSD-II mice. PMID:16987711

  4. Decoding the direction of imagined visual motion using 7T ultra-high field fMRI.

    PubMed

    Emmerling, Thomas C; Zimmermann, Jan; Sorger, Bettina; Frost, Martin A; Goebel, Rainer

    2016-01-15

    There is a long-standing debate about the neurocognitive implementation of mental imagery. One form of mental imagery is the imagery of visual motion, which is of interest due to its naturalistic and dynamic character. However, so far only the mere occurrence rather than the specific content of motion imagery was shown to be detectable. In the current study, the application of multi-voxel pattern analysis to high-resolution functional data of 12 subjects acquired with ultra-high field 7T functional magnetic resonance imaging allowed us to show that imagery of visual motion can indeed activate the earliest levels of the visual hierarchy, but the extent thereof varies highly between subjects. Our approach enabled classification not only of complex imagery, but also of its actual contents, in that the direction of imagined motion out of four options was successfully identified in two thirds of the subjects and with accuracies of up to 91.3% in individual subjects. A searchlight analysis confirmed the local origin of decodable information in striate and extra-striate cortex. These high-accuracy findings not only shed new light on a central question in vision science on the constituents of mental imagery, but also show for the first time that the specific sub-categorical content of visual motion imagery is reliably decodable from brain imaging data on a single-subject level. PMID:26481673

  5. Nebulin binding impedes mutant desmin filament assembly

    PubMed Central

    Baker, Laura K.; Gillis, David C.; Sharma, Sarika; Ambrus, Andy; Herrmann, Harald; Conover, Gloria M.

    2013-01-01

    Desmin intermediate filaments (DIFs) form an intricate meshwork that organizes myofibers within striated muscle cells. The mechanisms that regulate the association of desmin to sarcomeres and their role in desminopathy are incompletely understood. Here we compare the effect nebulin binding has on the assembly kinetics of desmin and three desminopathy-causing mutant desmin variants carrying mutations in the head, rod, or tail domains of desmin (S46F, E245D, and T453I). These mutants were chosen because the mutated residues are located within the nebulin-binding regions of desmin. We discovered that, although nebulin M160–164 bound to both desmin tetrameric complexes and mature filaments, all three mutants exhibited significantly delayed filament assembly kinetics when bound to nebulin. Correspondingly, all three mutants displayed enhanced binding affinities and capacities for nebulin relative to wild-type desmin. Electron micrographs showed that nebulin associates with elongated normal and mutant DIFs assembled in vitro. Moreover, we measured significantly delayed dynamics for the mutant desmin E245D relative to wild-type desmin in fluorescence recovery after photobleaching in live-cell imaging experiments. We propose a mechanism by which mutant desmin slows desmin remodeling in myocytes by retaining nebulin near the Z-discs. On the basis of these data, we suggest that for some filament-forming desmin mutants, the molecular etiology of desminopathy results from subtle deficiencies in their association with nebulin, a major actin-binding filament protein of striated muscle. PMID:23615443

  6. Anococcygeal Raphe Revisited: A Histological Study Using Mid-Term Human Fetuses and Elderly Cadavers

    PubMed Central

    Arakawa, Takashi; Abe, Hiroshi; Abe, Shinichi; Cho, Baik Hwan; Murakami, Gen; Sugihara, Kenichi

    2012-01-01

    Purpose We recently demonstrated the morphology of the anococcygeal ligament. As the anococcygeal ligament and raphe are often confused, the concept of the anococcygeal raphe needs to be re-examined from the perspective of fetal development, as well as in terms of adult morphology. Materials and Methods We examined the horizontal sections of 15 fetuses as well as adult histology. From cadavers, we obtained an almost cubic tissue mass containing the dorsal wall of the anorectum, the coccyx and the covering skin. Most sections were stained with hematoxylin and eosin or Masson-trichrome solution. Results The adult ligament contained both smooth and striated muscle fibers. A similar band-like structure was seen in fetuses, containing: 1) smooth muscle fibers originating from the longitudinal muscle coat of the anal canal and 2) striated muscle fibers from the external anal sphincter (EAS). However, in fetuses, the levator ani muscle did not attach to either the band or the coccyx. Along and around the anococcygeal ligament, we did not find any aponeurotic tissue with transversely oriented fibers connecting bilateral levator ani slings. Instead, in adults, a fibrous tissue mass was located at a gap between bilateral levator ani slings; this site corresponded to the dorsal side of the ligament and the EAS in the immediately deep side of the natal skin cleft. Conclusion We hypothesize that a classically described raphe corresponds to the specific subcutaneous tissue on the superficial or dorsal side of the anococcygeal ligament. PMID:22665356

  7. The Popeye domain containing 2 (popdc2) gene in zebrafish is required for heart and skeletal muscle development

    PubMed Central

    Kirchmaier, Bettina C.; Poon, Kar Lai; Schwerte, Thorsten; Huisken, Jan; Winkler, Christoph; Jungblut, Benno; Stainier, Didier Y.; Brand, Thomas

    2013-01-01

    The Popeye domain containing (Popdc) genes encode a family of transmembrane proteins with an evolutionary conserved Popeye domain. These genes are abundantly expressed in striated muscle tissue, however their function is not well understood. In this study we have investigated the role of the popdc2 gene in zebrafish. Popdc2 transcripts were detected in the embryonic myocardium and transiently in the craniofacial and tail musculature. Morpholino oligonucleotide-mediated knockdown of popdc2 resulted in aberrant development of skeletal muscle and heart. Muscle segments in the trunk were irregularly shaped and craniofacial muscles were severely reduced or even missing. In the heart, pericardial edema was prevalent in the morphants and heart chambers were elongated and looping was abnormal. These pathologies in muscle and heart were alleviated after reducing the morpholino concentration. However the heart still was abnormal displaying cardiac arrhythmia at later stages of development. Optical recordings of cardiac contractility revealed irregular ventricular contractions with a 2:1, or 3:1 atrial/ventricular conduction ratio, which caused a significant reduction in heart frequency. Recordings of calcium transients with high spatiotemporal resolution using a transgenic calcium indicator line (Tg(cmlc2:gCaMP)s878) and SPIM microscopy confirmed the presence of a severe arrhythmia phenotype. Our results identify popdc2 as a gene important for striated muscle differentiation and cardiac morphogenesis. In addition it is required for the development of the cardiac conduction system. PMID:22290329

  8. Expression of L-type calcium channels associated with postnatal development of skeletal muscle function in mouse.

    PubMed

    Mänttäri, S; Pyörnilä, A; Harjula, R; Järvilehto, M

    2001-01-01

    Several factors have an influence on the improvement of muscle activity and motor co-ordination of mammals during post-natal development. One of them is voltage sensitive L-type calcium channel function. In striated muscles of adult mammals these channels are located in T-tubule membranes thus linking the on-coming action potential to the molecular process of muscle contraction. The postnatal development of L-type calcium channels is therefore critical not only for contraction but also for all subsequent motor learning. We used high affinity enantiomer of dihydropyridine labelled with a fluorophore in order to show the relative amount of L-type calcium channels by histofluorescence in tissue. We found by qualitative microscopical analysis that the amount of L-type calcium channels increased during the postnatal development in the mouse skeletal muscle (m. rectus femoris and m. gastrocnemius). We also noted variation between different fibre types in the increase of the amount of L-type calcium channels, as judged by the intensity of histofluorescence. We showed by histochemical staining and statistical analysis that the high density of L-type calcium channels in adult muscles is correlated with fast oxidative glycolytic fibre type of striated muscles rather than slow oxidative or fast glycolytic fibres. Based on this finding we propose that the development of L-type calcium channels can be considered as one of the factors determining the different physiological properties of fibre types. PMID:11563550

  9. Titin stiffness modifies the force-generating region of muscle sarcomeres

    PubMed Central

    Li, Yong; Lang, Patrick; Linke, Wolfgang A.

    2016-01-01

    The contractile units of striated muscle, the sarcomeres, comprise the thick (myosin) and thin (actin) filaments mediating active contraction and the titin filaments determining “passive” elasticity. We hypothesized that titin may be more active in muscle contraction by directly modulating thick-filament properties. We used single-myofibril mechanical measurements and atomic force microscopy of individual sarcomeres to quantify the effects of sarcomere strain and titin spring length on both the inter-filament lattice spacing and the lateral stiffness of the actin-myosin overlap zone (A-band). We found that strain reduced the lattice spacing similarly in sarcomeres with stiff (rabbit psoas) or compliant titin (rabbit diaphragm), but increased A-band lateral stiffness much more in psoas than in diaphragm. The strain-induced alterations in A-band stiffness that occur independently of lattice spacing effects may be due to titin stiffness-sensing by A-band proteins. This mechanosensitivity could play a role in the physiologically important phenomenon of length-dependent activation of striated muscle. PMID:27079135

  10. The iojap gene in maize

    SciTech Connect

    Martienssen, Robert

    2001-12-01

    The classical maize mutant iojap (Iodent japonica) has variegated green and white leaves. Green sectors have cells with normal chloroplasts whereas white sectors have cells where plastids fail to differentiate. These mutant plastids, when transmitted through the female gametophyte, do not recover in the presence of wild type Iojap. We cloned the Ij locus, and we have investigated the mechanism of epigenetic inheritance and phenotypic expression. More recently, a modifier of this type of variegation, ''Inhibitor of striate'', has also been cloned. Both the iojap and inhibitor of striate proteins have homologs in bacteria and are members of ancient conserved families found in multiple species. These tools can be used to address fundamental questions of inheritance and variegation associated with this classical conundrum of maize genetics. Since the work of Rhoades there has been considerable speculation concerning the nature of the Iojap gene product, the origin of leaf variegation and the mechanism behind the material inheritance of defective plastids. This has made Iojap a textbook paradigm for cytoplasmic inheritance and nuclear-organellar interaction for almost 50 years. Cloning of the Iojap gene in maize, and homologs in other plants and bacteria, provides a new means to address the origin of heteroplastidity, variegation and cytoplasmic inheritance in higher plants.

  11. RICH-1 has a BIN/Amphiphysin/Rvsp domain responsible for binding to membrane lipids and tubulation of liposomes.

    PubMed

    Richnau, Ninna; Fransson, Asa; Farsad, Khashayar; Aspenström, Pontus

    2004-07-30

    RhoGAP interacting with CIP4 homologs-1 (RICH-1) was previously found in a yeast two-hybrid screen for proteins interacting with the SH3 domain of the Cdc42-interacting protein 4 (CIP4). RICH-1 was shown to be a RhoGAP for Cdc42 and Rac. In this study, we show that the BIN/Amphiphysin/Rvsp (BAR) domain in RICH-1 confers binding to membrane lipids, and has the potential to deform spherical liposomes into tubes. In accordance with previous findings for the BAR domains in endophilin and amphiphysin, RICH-1-induced tubes appeared striated. We propose that these striated structures are formed by oligomerization of RICH-1 through a putative coiled-coil region within the BAR domain. In support of this notion, we show that RICH-1 forms oligomers in the presence of the chemical cross-linker BS3. These results point to an involvement of RICH-1 in membrane deformation events. PMID:15240152

  12. Localization of sodium pump sites in cat salivary glands.

    PubMed Central

    Bundgaard, M; Møller, M; Poulsen, J H

    1977-01-01

    1. Cat submandibular glands were perfused with Locke solution containing [3H]ouabain. In some experiments additional medium was given by retrograde intraductal injection. 2. [3H]ouabain binding sites were localized by light microscopical autoradiography and the findings compared with the electron micrographs. 3. The cells of the striated ducts were heavily labelled with [3H]ouabain, predominantly in the contraluminal parts. 4. At the acinar level moderate amounts of [3H]ouabain were found in relation to the plasma membranes of the demilunar cells. The central acinar cells were found to be virtually devoid of [3H]ouabain. 5. Electron microscopy revealed that the demilunar cells possessed long, tortuous intercellular spaces separated from the secretory canaliculi by junctional complexes. In contrast, the membranes between adjacent central acinar cells were fairly straight. 6. It is concluded that the striated ducts play a dominant role in the ductal reabsorption of sodium, and that the transport is probably mediated by a (Na+ + K+)-activated ATPase. The findings on the acinar level are in agreement with the view that the primary saliva is formed predominantly by the demilunar cells. The role of a (Na+ + K+)-activated ATPase in this process is unclear. Images A B A B Plate 3 PMID:146078

  13. [Bilateral caudate head infarcts].

    PubMed

    Kuriyama, N; Yamamoto, Y; Akiguchi, I; Oiwa, K; Nakajima, K

    1997-11-01

    We reported a 67-year-old woman with bilateral caudate head infarcts. She developed sudden mutism followed by abulia. She was admitted to our hospital 2 months after ictus for further examination. She showed prominent abulia and was inactive, slow and apathetic. Spontaneous activity and speech, immediate response to queries, spontaneous word recall and attention and persistence to complex programs were disturbed. Apparent motor disturbance, gait disturbance, motor aphasia, apraxia and remote memory disturbance were not identified. She seemed to be depressed but not sad. Brain CT and MRI revealed bilateral caudate head hemorrhagic infarcts including bilateral anterior internal capsules, in which the left lesion was more extensive than right one and involved the part of the left putamen. These infarct locations were thought to be supplied by the area around the medial striate artery including Heubner's arteries and the A1 perforator. Digital subtraction angiography showed asymptomatic right internal carotid artery occlusion. She bad had hypertension, diabetes mellitus and atrial fibrillation and also had a left atrium with a large diameter. The infarcts were thought to be caused by cardioembolic occlusion to the distal portion of the left internal carotid artery. Although some variations of vasculature at the anterior communicating artery might contribute to bilateral medial striate artery infarcts, we could not demonstrate such abnormalities by angiography. Bilateral caudate head infarcts involving the anterior internal capsule may cause prominent abulia. The patient did not improve by drug and rehabilitation therapy and died suddenly a year after discharge. PMID:9503974

  14. Objective analysis of toolmarks in forensics

    NASA Astrophysics Data System (ADS)

    Grieve, Taylor N.

    Since the 1993 court case of Daubert v. Merrell Dow Pharmaceuticals, Inc. the subjective nature of toolmark comparison has been questioned by attorneys and law enforcement agencies alike. This has led to an increased drive to establish objective comparison techniques with known error rates, much like those that DNA analysis is able to provide. This push has created research in which the 3-D surface profile of two different marks are characterized and the marks' cross-sections are run through a comparative statistical algorithm to acquire a value that is intended to indicate the likelihood of a match between the marks. The aforementioned algorithm has been developed and extensively tested through comparison of evenly striated marks made by screwdrivers. However, this algorithm has yet to be applied to quasi-striated marks such as those made by the shear edge of slip-joint pliers. The results of this algorithm's application to the surface of copper wire will be presented. Objective mark comparison also extends to comparison of toolmarks made by firearms. In an effort to create objective comparisons, microstamping of firing pins and breech faces has been introduced. This process involves placing unique alphanumeric identifiers surrounded by a radial code on the surface of firing pins, which transfer to the cartridge's primer upon firing. Three different guns equipped with microstamped firing pins were used to fire 3000 cartridges. These cartridges are evaluated based on the clarity of their alphanumeric transfers and the clarity of the radial code surrounding the alphanumerics.

  15. A Novel Method of Urinary Sphincter Deficiency: Serial Histopathology Evaluation in a Rat Model of Urinary Incontinence.

    PubMed

    Khorramirouz, Reza; Mozafarpour, Sarah; Kameli, Seyedeh Maryam; Ladi Seyedian, Seyedeh Sanam; Oveisi, Nasim; Rahimi, Zahra; Alijani, Maryam; Kajbafzadeh, Abdol-Mohammad

    2016-02-01

    In this study, a novel technique of irreversible sphincter deficiency by pudendal nerve transection (PNT) using 40 female rats for studying the pathophysiology of stress urinary incontinence associated with childbirth was developed. Of the 40 rats, 10 served as controls and the remaining underwent bilateral PNT at the anastomotic lumbosacral trunk level. Urethral morphological changes following bilateral PNT were assessed with serial hematoxylin and eosin (H&E) and immunohistochemistry (IHC) staining methods at 50, 90, and 130 days post-intervention. Leak point pressure (LPP) measurement was used to determine the effect of pudendal injury on urethral outlet resistance after the transection. H&E and IHC staining showed irreversible loss of striated muscle mass of the sphincter region and increase in collagen deposition compatible with muscle atrophy. LPP measurements also significantly decreased following bilateral PNT. In conclusion, a novel method of irreversible sphincter insufficiency was developed. This model effectively decreased urethral outlet resistance and caused irreversible striated muscle atrophy. It was suggested that this technique can be used to develop a permanent sphincter deficiency model for the preclinical testing of treatment modalities exclusively triggering the pudendal nerve. PMID:26574901

  16. Loss of CDKN2A Promoter Methylation Coincides With the Epigenetic Transdifferentiation of Uterine Myosarcomatous Cells.

    PubMed

    Roncati, Luca; Barbolini, Giuseppe; Sartori, Giuliana; Siopis, Elena; Pusiol, Teresa; Maiorana, Antonio

    2016-07-01

    Leiomyosarcoma is the most common type of uterine sarcoma and usually displays typical morphology. Heterologous leiomyosarcoma is the rarest variant, in which the tumor contains liposarcomatous, osteosarcomatous, or rhabdomyosarcomatous components. We have investigated the largest series of uterine leiomyosarcoma with a rhabdomyosarcomatous component and we have disclosed a molecular finding, which coincides to the process of transdifferentiation from smooth muscle into striated muscle phenotype. The surgical specimens of 5 rare cases of uterine leiomyosarcoma with a rhabdomyosarcomatous component were formalin fixed and paraffin embedded. In addition to hematoxylin/eosin stains, phosphotungstic acid hematoxylin staining, immunohistochemistry, and methylation-specific polymerase chain reaction the CDKN2A promoter region were performed. Leiomyosarcomatous cells were found to be strongly immunoreactive for both desmin and α-smooth muscle actin. Rhabdomyosarcomatous cells were immunoreactive for sarcomeric actin, desmin, vimentin, CD10, and p16. The methylation-specific polymerase chain reaction revealed the presence of a methylated allele and an unmethylated allele in the microdissected samples, coming from leiomyosarcomatous cells. On the contrary, 2 unmethylated alleles, molecular expression of a loss of heterozygosity, were detected in all the microdissected samples in the rhabdomyosarcomatous cells. The loss of heterozygosity methylation in the promoter region of the CDKN2A gene, occurred only in the rhabdomyosarcomatous cells with increases in both p16 and p14 expression. This event may result in an inhibition of cdk4/cdk6 activity, stabilizes the tumor suppressor protein p53, and coincides with the transdifferentiation from smooth muscle into striated muscle. PMID:27276112

  17. Post-transcriptional regulation of myotube elongation and myogenesis by Hoi Polloi

    PubMed Central

    Johnson, Aaron N.; Mokalled, Mayssa H.; Valera, Juliana M.; Poss, Kenneth D.; Olson, Eric N.

    2013-01-01

    Striated muscle development requires the coordinated expression of genes involved in sarcomere formation and contractility, as well as genes that determine muscle morphology. However, relatively little is known about the molecular mechanisms that control the early stages of muscle morphogenesis. To explore this facet of myogenesis, we performed a genetic screen for regulators of somatic muscle morphology in Drosophila, and identified the putative RNA-binding protein (RBP) Hoi Polloi (Hoip). Hoip is expressed in striated muscle precursors within the muscle lineage and controls two genetically separable events: myotube elongation and sarcomeric protein expression. Myotubes fail to elongate in hoip mutant embryos, even though the known regulators of somatic muscle elongation, target recognition and muscle attachment are expressed normally. In addition, a majority of sarcomeric proteins, including Myosin Heavy Chain (MHC) and Tropomyosin, require Hoip for their expression. A transgenic MHC construct that contains the endogenous MHC promoter and a spliced open reading frame rescues MHC protein expression in hoip embryos, demonstrating the involvement of Hoip in pre-mRNA splicing, but not in transcription, of muscle structural genes. In addition, the human Hoip ortholog NHP2L1 rescues muscle defects in hoip embryos, and knockdown of endogenous nhp2l1 in zebrafish disrupts skeletal muscle development. We conclude that Hoip is a conserved, post-transcriptional regulator of muscle morphogenesis and structural gene expression. PMID:23942517

  18. Nerve conduction and electromyography studies.

    PubMed

    Kane, N M; Oware, A

    2012-07-01

    Nerve conduction studies (NCS) and electromyography (EMG), often shortened to 'EMGs', are a useful adjunct to clinical examination of the peripheral nervous system and striated skeletal muscle. NCS provide an efficient and rapid method of quantifying nerve conduction velocity (CV) and the amplitude of both sensory nerve action potentials (SNAPs) and compound motor action potentials (cMAPs). The CV reflects speed of propagation of action potentials, by saltatory conduction, along large myelinated axons in a peripheral nerve. The amplitude of SNAPs is in part determined by the number of axons in a sensory nerve, whilst amplitude of cMAPs reflects integrated function of the motor axons, neuromuscular junction and striated muscle. Repetitive nerve stimulation (RNS) can identify defects of neuromuscular junction (NMJ) transmission, pre- or post-synaptic. Needle EMG examination can detect myopathic changes in muscle and signs of denervation. Combinations of these procedures can establish if motor and/or sensory nerve cell bodies or peripheral nerves are damaged (e.g. motor neuronopathy, sensory ganglionopathy or neuropathy), and also indicate if the primary target is the axon or the myelin sheath (i.e. axonal or demyelinating neuropathies). The distribution of nerve damage can be determined as either generalised, multifocal (mononeuropathy multiplex) or focal. The latter often due to compression at the common entrapment sites (such as the carpal tunnel, Guyon's canal, cubital tunnel, radial groove, fibular head and tarsal tunnel, to name but a few of the reported hundred or so 'entrapment neuropathies'). PMID:22614870

  19. Palaeozoic nonmarine firmground ichnofaunas: evidence from the permian of the Paganzo basin

    USGS Publications Warehouse

    Buatois, L.A.; Mangano, M.G.; Acenolaza, F.G.

    1996-01-01

    Meniscate striated traces are recorded from Permian fluvial deposits of the La Colina Formation (Paganzo Group) at Los Colorados de Patqui??a (La Rioja Province). These structures are characterized by their remarkable well developed striations, oblique to the margins of unbranched and unwalled traces. Taxonomic assessment of these structures must await clarification of the actual nature of the ichnogenus Scoyenia and its relationship with Taenidium. They are interpreted as arthropod feeding structures (fodinichnia). Meniscate striated traces characterize firm substrates and crosscut a softground ichnofauna ascribed to the Scoyenia ichnofacies. Trace makers probably colonized the desiccated margins of a floodplain water body. A review of the ichnologic record of nonmarine firmgrounds shows the widespread establishment of trace fossils in cohesive sediments during the Mesozoic and only an incipient development during the Palaeozoic. The Palaeozoic examples undoubtely ascribed to invertebrates are known from the Permian and seem to record the displacement of organisms in the interface of a firm substrate, rather than burrowing activities within the cohesive sediment.

  20. AB101. Therapeutic effect of low intensity pulsed ultrasound in stress urinary incontinence

    PubMed Central

    Yang, Bicheng; Lei, Hongen; Guan, Ruili; Li, Huixi; Xin, Zhongcheng

    2016-01-01

    Objective Stress urinary incontinence, a major type of urinary incontinence, increases with age and is often developed after partum injury. Low intensity pulsed ultrasound (LIPUS) has been investigated in the treatment of many diseases showing its ability of restoring soft tissue injury. We investigated the therapeutic effect of low intensity pulsed ultrasound in stress urinary incontinence. Methods Thirty-two Sprague Dawley rats in SUI group underwent vaginal distension (VD) and bilateral ovariectomy mimicking partum injury. Eight rats served as mock operation control. Eight rats each in SUI group was treated with low-dosage LESW (0.03 mJ/mm2), medium-dosage LESW (0.06 mJ/mm2), or high-dosage LESW (0.09 mJ/mm2). The rest eight rats served as none-treatment group. For functional study, leak point pressure test (LPP) was performed 2 weeks after the last LESW. Masson trichrome staining was performed to validate the pathological changes. Results The LPP was restored in medium-dosage LESW and high-dosage LESW groups, but not in low-dosage LESW group. More robust striated muscle regeneration was found in these two groups comparing with the none-treatment group. Conclusions LIPUS ameliorate the symptom of SUI via activating striated muscle regeneration.

  1. Mesodermal iPSC–derived progenitor cells functionally regenerate cardiac and skeletal muscle

    PubMed Central

    Quattrocelli, Mattia; Swinnen, Melissa; Giacomazzi, Giorgia; Camps, Jordi; Barthélemy, Ines; Ceccarelli, Gabriele; Caluwé, Ellen; Grosemans, Hanne; Thorrez, Lieven; Pelizzo, Gloria; Muijtjens, Manja; Verfaillie, Catherine M.; Blot, Stephane; Janssens, Stefan; Sampaolesi, Maurilio

    2015-01-01

    Conditions such as muscular dystrophies (MDs) that affect both cardiac and skeletal muscles would benefit from therapeutic strategies that enable regeneration of both of these striated muscle types. Protocols have been developed to promote induced pluripotent stem cells (iPSCs) to differentiate toward cardiac or skeletal muscle; however, there are currently no strategies to simultaneously target both muscle types. Tissues exhibit specific epigenetic alterations; therefore, source-related lineage biases have the potential to improve iPSC-driven multilineage differentiation. Here, we determined that differential myogenic propensity influences the commitment of isogenic iPSCs and a specifically isolated pool of mesodermal iPSC-derived progenitors (MiPs) toward the striated muscle lineages. Differential myogenic propensity did not influence pluripotency, but did selectively enhance chimerism of MiP-derived tissue in both fetal and adult skeletal muscle. When injected into dystrophic mice, MiPs engrafted and repaired both skeletal and cardiac muscle, reducing functional defects. Similarly, engraftment into dystrophic mice of canine MiPs from dystrophic dogs that had undergone TALEN-mediated correction of the MD-associated mutation also resulted in functional striatal muscle regeneration. Moreover, human MiPs exhibited the same capacity for the dual differentiation observed in murine and canine MiPs. The findings of this study suggest that MiPs should be further explored for combined therapy of cardiac and skeletal muscles. PMID:26571398

  2. [Anatomy and physiology of sexuality].

    PubMed

    Cour, F; Droupy, S; Faix, A; Methorst, C; Giuliano, F

    2013-07-01

    Knowledge of the physiology of male and female sexuality has advanced considerably. Initially there is always desire with its biological neuroendocrine components and its emotional field which is particularly marked in women. There is a distinction between "spontaneous" sexual desire related to intrinsic affective, cognitive stimuli, and fantasies, and "reactive" sexual desire in response to physical arousal. There are similarities between men and women concerning the activation of cerebral zones in sexual arousal contexts in laboratory conditions. The neural pathways for sexual arousal are similar between men and women, bringing into play the sympathetic centres of the thoracic and lumbar spinal cord and, at the sacral level, the parasympathetic center and the motoneurons controlling the muscular contractions of the pelviperineal striated muscles. Genital sensitivity is mainly transmitted by the pudendal nerve in both men and women. Sexual arousal in men consists of penile erection, and ejaculation accompanied with orgasm. In women, sexual arousal causes increase in blood to flow to the vagina leading to lubrication and to the vulva leading to the erection of the clitoris and vulvar hyperaemia. The orgasm which can be multiple in women is accompanied by contractions of the striated perineal muscles. Several neurotransmitters are closely involved in the control of sexuality at the central level: dopamine, ocytocin, serotonin, and peripheral: nitric oxide and noradrenaline in men, vasoactive intestinal peptide and neuropeptide Y in women. PMID:23830249

  3. Nucleotide and protein sequences for dog masticatory tropomyosin identify a novel Tpm4 gene product.

    PubMed

    Brundage, Elizabeth A; Biesiadecki, Brandon J; Reiser, Peter J

    2015-10-01

    Jaw-closing muscles of several vertebrate species, including members of Carnivora, express a unique, "masticatory", isoform of myosin heavy chain, along with isoforms of other myofibrillar proteins that are not expressed in most other muscles. It is generally believed that the complement of myofibrillar isoforms in these muscles serves high force generation for capturing live prey, breaking down tough plant material and defensive biting. A unique isoform of tropomyosin (Tpm) was reported to be expressed in cat jaw-closing muscle, based upon two-dimensional gel mobility, peptide mapping, and immunohistochemistry. The objective of this study was to obtain protein and gene sequence information for this unique Tpm isoform. Samples of masseter (a jaw-closing muscle), tibialis (predominantly fast-twitch fibers), and the deep lateral gastrocnemius (predominantly slow-twitch fibers) were obtained from adult dogs. Expressed Tpm isoforms were cloned and sequencing yielded cDNAs that were identical to genomic predicted striated muscle Tpm1.1St(a,b,b,a) (historically referred to as αTpm), Tpm2.2St(a,b,b,a) (βTpm) and Tpm3.12St(a,b,b,a) (γTpm) isoforms (nomenclature reflects predominant tissue expression ("St"-striated muscle) and exon splicing pattern), as well as a novel 284 amino acid isoform observed in jaw-closing muscle that is identical to a genomic predicted product of the Tpm4 gene (δTpm) family. The novel isoform is designated as Tpm4.3St(a,b,b,a). The myofibrillar Tpm isoform expressed in dog masseter exhibits a unique electrophoretic mobility on gels containing 6 M urea, compared to other skeletal Tpm isoforms. To validate that the cloned Tpm4.3 isoform is the Tpm expressed in dog masseter, E. coli-expressed Tpm4.3 was electrophoresed in the presence of urea. Results demonstrate that Tpm4.3 has identical electrophoretic mobility to the unique dog masseter Tpm isoform and is of different mobility from that of muscle Tpm1.1, Tpm2.2 and Tpm3.12 isoforms. We

  4. Nucleotide and protein sequences for dog masticatory tropomyosin identify a novel Tpm4 gene product

    PubMed Central

    Reiser, Peter J.

    2016-01-01

    Jaw-closing muscles of several vertebrate species, including members of Carnivora, express a unique, “masticatory”, isoform of myosin heavy chain, along with isoforms of other myofibrillar proteins that are not expressed in most other muscles. It is generally believed that the complement of myofibrillar isoforms in these muscles serves high force generation for capturing live prey, breaking down tough plant material and defensive biting. A unique isoform of tropomyosin (Tpm) was reported to be expressed in cat jaw-closing muscle, based upon two-dimensional gel mobility, peptide mapping, and immunohistochemistry. The objective of this study was to obtain protein and gene sequence information for this unique Tpm isoform. Samples of masseter (also a jaw-closing muscle), tibialis (with predominantly fast-twitch fibers), and the deep lateral gastrocnemius (predominantly slow-twitch fibers) were obtained from adult dogs. Expressed Tpm isoforms were cloned and sequencing yielded cDNAs that were identical to genomic predicted striated muscle Tpm1.1St(a,b,b,a) (historically referred to as αTpm), Tpm2.2St(a,b,b,a) (βTpm) and Tpm3.12St(a,b,b,a) (cTpm) isoforms (nomenclature reflects predominant tissue expression (“St”—striated muscle) and exon splicing pattern), as well as a novel 284 amino acid isoform observed in jaw-closing muscle that is identical to a genomic predicted product of the Tpm4 gene (δTpm) family. The novel isoform is designated as Tpm4.3St(a,b,b,a). The myofibrillar Tpm isoform expressed in dog masseter exhibits a unique electrophoretic mobility on gels containing 6 M urea, compared to other skeletal Tpm isoforms. To validate that the cloned Tpm4.3 isoform is the Tpm expressed in dog masseter, E. coli-expressed Tpm4.3 was electrophoresed in the presence of urea. Results demonstrate that Tpm4.3 has identical electrophoretic mobility to the unique dog masseter Tpm isoform and is of different mobility from that of muscle Tpm1.1, Tpm2.2 and Tpm3

  5. Chicxulub Impact Ejecta in Belize

    NASA Technical Reports Server (NTRS)

    Ocampo, A.; Pope, K.; Fischer, A.; Alvarez, W.; Fouke, B.; Asaro, F.; Webster, C., Jr.; Vega, F.; Smith, J.; Fritsche, A. E.

    1997-01-01

    Chicxulub ejecta deposits in Belize provide the closest exposures of ejecta to the crater and the only exposures of proximal ejecta deposited in a terrestrial environment. A quarry on Albion Island in northern Belize exposes Late Cretaceous, possibly Maastrichtian, carbonate platform sediments that were folded, eroded, and subaerially weathered prior to the deposition of coarse ejecta from Chicxulub. These ejecta deposits are composed of a basal, about 1-m-thick clay and dolomite Spheroid Bed overlain by a about 15-m-thick coarse Diamictite Bed. Many and perhaps most of the clay spheroids are altered glass. Many dolomite spheroids have concentric layers and angular cores are probably of accretionary lapilli origin. A slight Ir concentration (111-152 ppt) was detected in the base of the Spheroid Bed. The Diamictite Bed contains about 10% altered glass, rare shocked quartz, 3-8 m diameter boulders and striated and polished cobbles, one with a penetrating rock chip that plastically deformed the cobble. Ejecta deposits extend to the surface at Albion and the maximum thickness in this area is not known. Ejecta deposits are exposed in several roadside quarries in the Cayo District of central Belize. The Late Cretaceous here is also represented by carbonate platform sediments. The upper surface of the carbonate platform is a highly irregular and extensively recrystallized horizon possibly representing deep karst weathering. Approximately 30 in of diamictite overlies this horizon with a texture similar to the Diamictite Bed at the Albion quarry, but with a more diverse lithology. In three locations the Cayo diamictites, contain red clay layers with abundant polished and striated limestone pebbles and cobbles called Pook's Pebbles, several of which have penetrating rock chips and ablated surfaces. We interpret the Albion Spheroid Bed as a deposit from the impact vapor plume and the Albion and Cayo diamictites as the result of a turbulent flow that contained debris derived

  6. Three novel brain tropomyosin isoforms are expressed from the rat alpha-tropomyosin gene through the use of alternative promoters and alternative RNA processing.

    PubMed Central

    Lees-Miller, J P; Goodwin, L O; Helfman, D M

    1990-01-01

    cDNA clones encoding three novel tropomyosins, termed TMBr-1, TMBr-2, and TMBr-3, were isolated and characterized from a rat brain cDNA library. All are derived from a single gene, which was previously found to express striated muscle alpha-tropomyosin and a number of other tropomyosin isoforms via an alternative splicing mechanism (N. Ruiz-Opazo and B. Nadal-Ginard, J. Biol. Chem. 262:4755-4765, 1987; D. F. Wieczorek, C. W. J. Smith, and B. Nadal-Ginard, Mol. Cell. Biol. 8:679-694, 1988). The derived amino acid sequences revealed that TMBr-1 contains 281 amino acids, TMBr-2 contains 251 amino acids, and TMBr-3 contains 245 amino acids. All three proteins contain a region that is identical to amino acids 81 through 258 of skeletal muscle alpha-tropomyosin. TMBr-1 is identical to striated muscle alpha-tropomyosin from amino acids 1 through 258 but contains a novel COOH-terminal region from amino acids 259 through 281. TMBr-2 and TMBr-3 both contain identical NH2-terminal sequences from amino acids 1 through 44 which were found to be expressed from a novel promoter. TMBr-3 contains the same COOH-terminal region as TMBr-1, whereas TMBr-2 contains a second novel COOH-terminal region. The genomic organization of the exons encoding TMBr-1, TMBr-2, and TMBr-3 were determined. These studies revealed a previously uncharacterized promoter located in the internal region of the alpha-TM gene as well as two novel COOH-terminal coding exons. The alpha-TM gene is a complex transcription unit containing 15 exons including two alternative promoters, two internal mutually exclusive exon cassettes, and four alternatively spliced 3' exons that encode four different COOH-terminal coding regions. A total of nine distinct mRNAs are known to be expressed from the alpha-TM gene in a cell type-specific manner in tissues such as striated muscle, smooth muscle, kidney, liver, brain, and fibroblasts. The mRNAs encoding TMBr-1, TMBr-2, and TMBr-3 were found to be expressed only in brain tissue

  7. Histo-topographic study of the longitudinal anal muscle.

    PubMed

    Macchi, Veronica; Porzionato, Andrea; Stecco, Carla; Vigato, Enrico; Parenti, Anna; De Caro, Raffaele

    2008-07-01

    The longitudinal anal muscle (LAM) has been described as a vertical layer of muscular tissue interposed between the circular layers of the internal (IAS) and external (EAS) anal sphincters. There is, however, no general agreement in the literature on its composition and attachments. The aim of this study was to investigate the histological structure, attachments, and topography of the LAM in order to evaluate its role in continence and defecation, thus enhancing knowledge of the surgical anatomy of this region. After in situ formalin fixation, the pelvic viscera were removed from eight male and eight female cadavers (age range: 52-72 years). Serial macrosections of the bladder base, lower rectum and anal canal, cervix and pelvic floor complex, cut in the transverse (six specimens) and coronal (six specimens) planes, underwent histological and immunohistochemical studies. Four specimens were studied using the E12 sheet plastination technique. The LAM was identified in 10/12 specimens (83%). Transverse and coronal sections made clear that it is a longitudinal layer of muscular tissue, marking the boundary between the internal and external anal sphincters. From the anorectal junction it extends along the anal canal, receives fibers from the innermost part of the puborectalis and the puboanalis muscles, and terminates with seven to nine fibro-elastic septa, which traverse the subcutaneous part of the external anal sphincter, reaching the perianal dermis. In the transverse plane, the mean thickness of the LAM was 1.68 +/- 0.27 mm. Immunohistochemical staining showed that the LAM consists of predominantly outer striated muscle fibers and smaller numbers of inner smooth muscle fibers, respectively coming from the levator ani muscle and from the longitudinal muscular layer of the rectum. The oblique fibers suggest that the LAM may represent the intermediate longitudinal course of small bridging muscle bundles going reciprocally from the striated EAS to the smooth IAS and

  8. Late Permian Palynology and depositional environment of Chintalapudi sub basin, Pranhita-Godavari basin, Andhra Pradesh, India

    NASA Astrophysics Data System (ADS)

    Jha, Neerja; Pauline Sabina, K.; Aggarwal, Neha; Mahesh, S.

    2014-01-01

    The present study deals with the palynological dating, correlation and depositional setting of the sediments from bore cores MGP-11 and MGP-4 from Gauridevipet area of Chintalapudi sub-basin of Godavari master basin, south India. On the basis of palynological studies, three palynoassemblages have been identified, one in bore core MGP-11 a Faunipollenites (=Protohaploxypinus) and Striasulcites assemblage and two in bore core MGP-4; one is characterized by the dominance of striate bisaccates and Densipollenites and the other by Striatopodocarpites and Cresentipollenites palynoassemblages. The other stratigraphically significant taxa include Guttulapollenites hannonicus, Lunatisporites noviaulensis, Lunatisporites pellucidus, Densoisporites contactus, Chordasporites australiensis, Goubinispora spp., Lundbladispora microconata, Lundbladispora raniganjensis and Klausipollenites schaubergeri. The recovered taxa suggest a Late Permian, Lopingian age for these rocks. This interpretation is based on the correlation of the assemblages with similar assemblages from previous Gondwana studies chiefly Densipollenites magnicorpus Zone of Damodar Basin, India and Late Permian palynoassemblages from Africa, Antarctica, Australia and South America. On the basis of palaeobotanical affinity of the identified microflora it has been inferred that the peat forming plant community was composed mainly of gymnosperm pollen attributable to glossopterids, that includes striate and non-striate bisaccates and paucity of cordaites which includes monosaccates. Spores are subordinate and are derived from lycopsids (Lundbladispora, Densoisporites), sphenopsids (Latosporites) and filicopsids (Horriditriletes, Lophotriletes, Verrucosisporites, Osmundacidites, Leiotriletes, Callumispora, Brevitriletes and Microbaculispora) occurring in variable proportions. The dominance of subarborescent/arborescent vegetation suggests a development in a forest swamp probably in a small distant marginal part of the

  9. Pure Motor Stroke Secondary to Cerebral Infarction of Recurrent Artery of Heubner after Mild Head Trauma: A Case Report

    PubMed Central

    Yilmaz, Ali; Kizilay, Zahir; Ozkul, Ayca; Çirak, Bayram

    2016-01-01

    BACKGROUND: The recurrent Heubner’s artery is the distal part of the medial striate artery. Occlusion of the recurrent artery of Heubner, classically contralateral hemiparesis with fasciobrachiocrural predominance, is attributed to the occlusion of the recurrent artery of Heubner and is widely known as a stroke syndrome in adults. However, isolated occlusion of the deep perforating arteries following mild head trauma also occurs extremely rarely in childhood. CASE REPORT: Here we report the case of an 11-year-old boy with pure motor stroke. The brain MRI showed an acute ischemia in the recurrent artery of Heubner supply area following mild head trauma. His fasciobrachial hemiparesis and dysarthria were thought to be secondary to the stretching of deep perforating arteries leading to occlusion of the recurrent artery of Heubner. CONCLUSION: Post-traumatic pure motor ischemic stroke can be secondary to stretching of the deep perforating arteries especially in childhood.

  10. Fourteen new species of Heterospilus Haliday (Hymenoptera, Braconidae: Doryctinae) from Brazil.

    PubMed

    Chiletto, Bo; Penteado-Dias, Am

    2016-01-01

    Fourteen new species of the genus Heterospilus Haliday found in semideciduous mesophilic forest areas at São Paulo State, Brazil are described. They are: Heterospilus ayewai sp. n., H. caetetus sp. n., H. fernandesi sp. n., H. fiorelinii sp. n., H. granulosus sp. n., H. homalos sp. n., H. intervalesi sp. n., H. japi sp.n., H. meloi sp. n., H. mesopleuron sp. n., H. periotoi sp. n., H. riveroni sp. n., H. sormusi sp. n., and H. virginensis sp. n. Heterospilus species are characterized by the sculpturation of the vertex: granulate, striate, rugose, or smooth, without sculpturation. All specimens of Heterospilus in this study are in the species group with a smooth, unsculptured vertex. PMID:27470859

  11. Physiology of the upper segment, body, and lower segment of the esophagus

    PubMed Central

    Miller, Larry; Clavé, Pere; Farré, Ricard; Lecea, Begoña; Ruggieri, Michael R.; Ouyang, Ann; Regan, Julie; McMahon, Barry P.

    2014-01-01

    The following discussion on the physiology of the esophagus includes commentaries on the function of the muscularis mucosa and submucosa as a mechanical antireflux barrier in the esophagus; the different mechanisms of neurological control in the esophageal striated and smooth muscle; new insights from animal models into the neurotransmitters mediating lower esophageal sphincter (LES) relaxation, peristalsis in the esophageal body (EB), and motility of esophageal smooth muscle; differentiation between in vitro properties of the lower esophageal circular muscle, clasp muscle, and sling fibers; alterations in the relationship between pharyngeal contraction and relaxation of the upper esophageal sphincter (UES) in patients with dysphagia; the mechanical relationships between anterior hyoid movement, the extent of upper esophageal opening, and aspiration; the application of fluoroscopy and manometry with biomechanics to define the stages of UES opening; and nonpharmacological approaches to alter the gastroesophageal junction (GEJ). PMID:24117648

  12. A conserved Six-Eya cassette acts downstream of Wnt signaling to direct non-myogenic versus myogenic fates in the C. elegans postembryonic mesoderm.

    PubMed

    Amin, Nirav M; Lim, Sung-Eun; Shi, Herong; Chan, Tiffany L; Liu, Jun

    2009-07-15

    The subdivision of mesodermal cells into muscle and non-muscle cells is crucial to animal development. In the C. elegans postembryonic mesoderm, this subdivision is a result of an asymmetric cell division that leads to the formation of striated body wall muscles and non-muscle coelomocytes. Here we report that the Six homeodomain protein CEH-34 and its cofactor Eyes Absent, EYA-1, function synergistically to promote the non-muscle fate in cells also competent to form muscles. We further show that the asymmetric expression of ceh-34 and eya-1 is regulated by a combination of 1) mesodermal intrinsic factors MAB-5, HLH-1 and FOZI-1, 2) differential POP-1 (TCF/LEF) transcriptional activity along the anterior-posterior axis, and 3) coelomocyte competence factor(s). These factors are conserved in both vertebrates and invertebrates, suggesting a conserved paradigm for mesoderm development in metazoans. PMID:19427847

  13. Fine structure of the parotid gland in tree shrew (Tupaia glis).

    PubMed

    Suzuki, S; Mifune, H; Nishida, T; Obara, T; Kamimura, R; Sakamoto, H; Mohammad Abdul, A; Nishinakagawa, H

    1995-10-01

    The parotid glands of Tupaia glis were examined by light and transmission electron microscopy. The acinar cells were seromucous in nature, and contained many acidophilic granules with strong affinity for periodic acid-Schiff (PAS) and weak affinity for alcian blue (AB). These granules consisted of a fine granular matrix of moderate density in which a denser corpuscles or semilunar materials were present. Intercalated duct cells had a few fine vesicles, vacuoles and very few dense granules in the apical region. In occasional epithelial cells, acidophilic, PAS-positive and AB-negative bodies with moderate density were observed in the supranuclear region. The striated ducts consisted of columnar light and dark cells containing round or small ovoid granules of moderate density and did not show the granular duct as seen in the parotid glands of kobe mole and tenrec which are placed in the order insectivora. PMID:8575539

  14. The local subsurface water and chlorine distributions evaluated by DAN/MSL in Curiosity observational campaigns

    NASA Astrophysics Data System (ADS)

    Litvak, Maxim; Mitrofanov, Igor; Hardgrove, Craig; Sanin, Anton; Lisov, Denis; Golovin, Dmitry; Jun, Insoo; Kozyrev, Alexander; Malakhov, Alexey; Mischna, Michael; Moersch, Jeffrey; Nikiforov, Sergey; Tate, Cristopher; Vostrukhin, Andrey

    2016-04-01

    The measurements with the Dynamic Albedo of Neutrons (DAN) instrument onboard the Mars Science Laboratory (MSL) Curiosity rover are presented and analyzed as a summary of observations acquired during several special observational campaigns at the Yellowknife Bay area (first discovery of habitability environment), at the striated units of Kimberley formation, at outcrops studied in Pahrump Hills (at the base of Mt Sharp) and in high silica area discovered in Marias Pass (Mudstone facies of the Murray formation). DAN data were analyzed to test local and global variability in the distribution of bulk hydrogen and neutron-absorbing elements, characterized as chlorine-equivalent concentration. Using multi instrument approach in the data analysis we have compared DAN estimations of subsurface H and Cl distributions with inhomogeneity of local geological context, top surface measurements of chlorine with APXS and with SAM measurements of absorbed H2O extracted from the drilled samples based on low temperature evolved gas analysis.

  15. The solution of the Elrod algorithm for a dynamically loaded journal bearing using multigrid techniques

    NASA Technical Reports Server (NTRS)

    Woods, Claudia M.; Brewe, David E.

    1988-01-01

    A numerical solution to a theoretical model of vapor cavitation in a dynamically loaded journal bearing is developed utilizing a multigrid iteration technique. The method is compared with a noniterative approach in terms of computational time and accuracy. The computational model is based on the Elrod algorithm, a control volume approach to the Reynolds equation which mimics the Jakobsson-Floberg and Olsson cavitation theory. Besides accounting for a moving cavitation boundary and conservation of mass at the boundary, it also conserves mass within the cavitated region via a smeared mass or striated flow extending to both surfaces in the film gap. The mixed nature of the equations (parabolic in the full film zone and hyperbolic in the cavitated zone) coupled with the dynamic aspects of the problem create interesting difficulties for the present solution approach. Emphasis is placed on the methods found to eliminate solution instabilities. Excellent results are obtained for both accuracy and reduction of computational time.

  16. Nitrotyrosine-modified SERCA2: a cellular sensor of reactive nitrogen species

    SciTech Connect

    Bigelow, Diana J.

    2009-01-19

    The SERCA2 isoform of the sarco/endoplasmic reticulum Ca2+-ATPase is sensitive to cellular conditions of inflammation and oxidative stress as evidenced by the common appearance of 3-nitrotyrosine modified forms of SERCA2 in aging and disease in both striated and smooth muscle of humans and several rodent models. Structural-functional studies of nitrated SERCA2 in aging heart and skeletal muscle demonstrate stoichiometric nitration of vicinal tyrosines, Tyr-294 and Tyr-295, on the lumenal side of the membrane-spanning helix, M4 that correlates with partial inhibition of its Ca2+-ATPase activity suggesting a possible regulatory function in down-regulating mitochondrial energy production and the associated generation of reactive oxygen/nitrogen species. This review discusses recent work regarding the nitrative and redox sensitivity of SERCA2 in muscle with respect to general cellular mechanisms of turnover and repair of modified proteins.

  17. Cysticercosis of Externsor Carpi Ulnaris – A differential diagnosis for painful swelling at elbow

    PubMed Central

    Agarwal, Sharat; Akhtar, Mohammad Nasim

    2011-01-01

    Introduction: Cysticercosis is an infection by the larval stage (cystcercus cellulosae) of the cestode, Taenia Solium (pork tape worm). It occurs especially in those individuals who live in the endemic areas. After gaining entry into the body, the larva become encysted and may lie in subcutaneous tissue, striated muscle, vitreous humor, or other tissues. Case report: We report an unusual case of cysticercosis of the Extensor carpi ulnaris (ECU) muscle, which presented as localized swelling at the lateral aspect of elbow. The diagnosis was confirmed on the musculoskeletal ultrasonographic examination of the elbow. It revealed the Cysticercus cellulosae as hyperechoic lesion surrounded by fluid. MRI was done later which localized the larval stage in the Extensor carpi ulnaris muscle at elbow. Conclusion: For swelling in the region of elbow in endemic areas of tapeworm infestations, the differential diagnosis of muscle cysticercosis should be kept in mind.

  18. Emotional expressions modulate low α and β oscillations in a cortically blind patient.

    PubMed

    Del Zotto, Marzia; Deiber, Marie-Pierre; Legrand, Lore Billie; De Gelder, Beatrice; Pegna, Alan John

    2013-12-01

    Studies of cortical blindness have suggested that some residual visual function may persist without perceptual awareness, a condition known as blindsight. To investigate electrophysiological evidence of unconscious processing of emotional stimuli, we examined the event-related oscillations (EROs) in a 62year-old male patient (TN) with affective blindsight during random stimulation of three facial expressions (fearful, happy and neutral). Spectral power analysis in response to the different emotions revealed significant differences between fearful and happy faces over the right frontal regions at 7-8Hz (low α), and between emotional and neutral faces over the left frontal sites at 12-13Hz (low β) in a time period between 100-400ms after visual stimulus onset. These results demonstrate that emotional face processing occurs very early in time in the absence of any functional striate cortex, and further reveals the existence of specific oscillatory frequencies that reflect unconscious processing of facial expressions in affective blindsight. PMID:24144636

  19. Sarcocystis eothenomysi n. sp. (Apicomplexa: Sarcocystidae) from the large oriental vole Eothenomys miletus (Thomas) (Cricetidae: Microtinae) from Anning, China.

    PubMed

    Hu, Jun-Jie; Liu, Qiong; Yang, Yan-Fen; Esch, Gerald W; Guo, Yan-Mei; Zou, Feng-Cai

    2014-09-01

    Fifty-six oriental voles, Eothenomys miletus (Thomas), were collected in Anning prefecture of Yunnan Province (China) between March 2012 and December 2013 and examined for the presence of sarcocysts. Sarcosysts of a new species, Sarcocystis eothenomysi n. sp., were found in 14 out of 56 E. miletus (25%); they possessed a striated cyst wall, c.1-2 μm thick. Under transmission electron microscopy the cysts of S. eothenomysi exhibited numerous small, irregular protrusions, which may appear T-shaped in some sections. A phylogenetic analysis based on 18S rRNA gene sequences indicated that S. eothenomysi shares closest affinity with those species of Sarcocystis Lankester, 1982, which use cobra or viperid snakes as definitive hosts. We therefore, hypothesise that a venomous snake may serve as the definitive host for S. eothenomysi. This is the first species of Sarcocystis reported from Eothenomys spp. PMID:25079817

  20. Mesocestoides lineatus (Goeze, 1782) (Mesocestoididae): new data on sperm ultrastructure.

    PubMed

    Miquel, Jordi; Eira, Catarina; Swiderski, Zdzisław; Conn, David Bruce

    2007-06-01

    Spermiogenesis and the ultrastructural characters of the spermatozoon of Mesocestoides lineatus are described by means of transmission electron microscopy, including cytochemical analysis for glycogen. Materials were obtained from a golden hamster (Mesocricetus auratus) after experimental infection with tetrathyridia metacestodes obtained from naturally infected lizards (Anolis carolinensis) from Louisiana. Spermiogenesis in M. lineatus is characterized by the orthogonal growth of a free flagellum, a flagellar rotation, and a proximodistal fusion. The zone of differentiation contains 2 centrioles associated with striated rootlets and a reduced intercentriolar body. The mature spermatozoon of M. lineatus lacks a mitochondrion, and it is characterized by the presence of (1) a single, spiraled, crested body 150 nm thick; (2) a single axoneme of the 9+'1' pattern of trepaxonematan Platyhelminthes; (3) a parallel and reduced row of submembranous cortical microtubules; (4) a spiraled cordon of glycogen granules; and (5) a spiraled nucleus encircling the axoneme. PMID:17626346

  1. Protein machines and self assembly in muscle organization

    NASA Technical Reports Server (NTRS)

    Barral, J. M.; Epstein, H. F.

    1999-01-01

    The remarkable order of striated muscle is the result of a complex series of protein interactions at different levels of organization. Within muscle, the thick filament and its major protein myosin are classical examples of functioning protein machines. Our understanding of the structure and assembly of thick filaments and their organization into the regular arrays of the A-band has recently been enhanced by the application of biochemical, genetic, and structural approaches. Detailed studies of the thick filament backbone have shown that the myosins are organized into a tubular structure. Additional protein machines and specific myosin rod sequences have been identified that play significant roles in thick filament structure, assembly, and organization. These include intrinsic filament components, cross-linking molecules of the M-band and constituents of the membrane-cytoskeleton system. Muscle organization is directed by the multistep actions of protein machines that take advantage of well-established self-assembly relationships. Copyright 1999 John Wiley & Sons, Inc.

  2. Centimeter to Decimeter Size Spherical and Cylindrical Features in Gale Crater Sediments

    NASA Technical Reports Server (NTRS)

    Wiens, R. C.; Maurice, S.; Gasnault, O.; Clegg, S.; Fabre, C.; Nachon, M.; Rubin, D.; Goetz, W.; Mangold, N.; Schroeder, S.; Rapin, W.; Milliken, R.; Fairen, A. G.; Oehler, D.; Forni, O.; Sautter, V.; Blaney, D.; Le Moulelic, S.; Anderson, R. B.; Cousin, A.; Vasavada, A.; Grotzinger, J.

    2015-01-01

    The Curiosity rover traverse in Gale crater has explored a large series of sedimentary deposits in an ancient lake on Mars. Over the nine kilometers of traverse a recurrent observation has been southward-dipping sedimentary strata, from Shaler at the edge of Yellowknife Bay to the striated units near the Kimberley. Within the sedimentary strata cm- to decimeter- size hollow spheroidal objects and some apparent cylindrical objects have been observed. These features have not been seen by previous landed missions. The first of these were observed on sol 122 in the Gillespie Lake member at Yellowknife Bay. Additional hollow features were observed in the Point Lake outcrop in the same area. More recently a spherical and apparently hollow object, Winnipesaukee, was observed by ChemCam and Mastcam on sol 653. Here we describe the settings, morphology, and associated compositions, and we discuss possible origins of these objects.

  3. Spontaneous extraskeletal osteosarcoma with various histological growth patterns in the abdominal wall of an ICR mouse

    PubMed Central

    Ito, Tsuyoshi; Katoh, Yoshitaka; Shimada, Yuko; Ohnuma-Koyama, Aya; Takahashi, Naofumi; Kuwahara, Maki; Harada, Takanori

    2015-01-01

    Extraskeletal osteosarcoma is extremely rare in mice. This case report demonstrates a spontaneous murine extraskeletal osteosarcoma that exhibited various histological growth patterns in an ICR mouse. At necropsy, the tumor mass was located in the abdominal wall and was 45 × 30 × 25 mm in size. Histopathologically, the tumor showed the following four growth patterns: a solid pattern of polygonal cells embedded in an osteoid eosinophilic matrix with calcification, an irregular sheet pattern of short spindle cells accompanying some eosinophilic multinucleated cells, a fascicular pattern of spindle cells and a cystic pattern lined by short spindle cells. Immunohistochemically, most of the tumor cells were positive for vimentin, proliferating cell nuclear antigen and osterix. The multinucleated cells mentioned above were desmin positive and were regarded as regenerative striated muscles but not tumor cells. Since no clear continuity with normal bone tissues was observed, the tumor was diagnosed as an “extraskeletal osteosarcoma.” PMID:26989300

  4. Dystrophin-Deficient Cardiomyopathy.

    PubMed

    Kamdar, Forum; Garry, Daniel J

    2016-05-31

    Dystrophinopathies are a group of distinct neuromuscular diseases that result from mutations in the structural cytoskeletal Dystrophin gene. Dystrophinopathies include Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD), X-linked dilated cardiomyopathy, as well as DMD and BMD female carriers. The primary presenting symptom in most dystrophinopathies is skeletal muscle weakness. However, cardiac muscle is also a subtype of striated muscle and is similarly affected in many of the muscular dystrophies. Cardiomyopathies associated with dystrophinopathies are an increasingly recognized manifestation of these neuromuscular disorders and contribute significantly to their morbidity and mortality. Recent studies suggest that these patient populations would benefit from cardiovascular therapies, annual cardiovascular imaging studies, and close follow-up with cardiovascular specialists. Moreover, patients with DMD and BMD who develop end-stage heart failure may benefit from the use of advanced therapies. This review focuses on the pathophysiology, cardiac involvement, and treatment of cardiomyopathy in the dystrophic patient. PMID:27230049

  5. The polyvagal theory: New insights into adaptive reactions of the autonomic nervous system

    PubMed Central

    PORGES, STEPHEN W.

    2011-01-01

    The polyvagal theory describes an autonomic nervous system that is influenced by the central nervous system, sensitive to afferent influences, characterized by an adaptive reactivity dependent on the phylogeny of the neural circuits, and interactive with source nuclei in the brainstem regulating the striated muscles of the face and head. The theory is dependent on accumulated knowledge describing the phylogenetic transitions in the vertebrate autonomic nervous system. Its specific focus is on the phylogenetic shift between reptiles and mammals that resulted in specific changes to the vagal pathways regulating the heart. As the source nuclei of the primary vagal efferent pathways regulating the heart shifted from the dorsal motor nucleus of the vagus in reptiles to the nucleus ambiguus in mammals, a face–heart connection evolved with emergent properties of a social engagement system that would enable social interactions to regulate visceral state. PMID:19376991

  6. Cardiomyocytes beat best on a matrix with heart-like elasticity -- Molecular mechanics of the changes

    NASA Astrophysics Data System (ADS)

    Carag, Christine; Engler, Adam; Discher, Dennis

    2009-03-01

    Cardiomyocytes derived from embryos beat spontaneously in culture, but it is shown here with a series of flexible substrates that matrices which mimic the elasticity of the developing heart are optimal for 1-Hz beating, for transmitting contractile work to the matrix, and for promoting actomyosin striation. On hard matrices that mechanically mimic a post-infarct fibrotic scar, cells overstrain themselves, lack striated myofibrils and stop beating; on very soft matrices, cells preserve contractile beating for days in culture but do very little work. Optimal matrix leads to a strain match between cell and matrix, and suggests dynamic differences in intracellular protein structures. A novel `cysteine shotgun' method of labeling the in situ proteome reveals differences in assembly or conformation of several abundant cytoskeletal proteins, including vimentin, filamin and myosin.

  7. [Embrionary-larval development of the tropical fish Hemirhamphus brasiliensis (Beloniformes: Hemirhamphidae) from eggs collected in the wild].

    PubMed

    Rosas, Jesús; Mata, Ernesto; Velásquez, Aidé; Cabrera, Tomas

    2008-09-01

    The embryo formation and larval development of Hemirhamphus brasiliensis Linnaeus, 1758 (Pisces: Hemirhamphidae) is described from morula stage eggs collected on Sargassum sp. Thalii in the field (10 degrees 50'55.2" N y 64 degrees 09'467" W). The eggs were spherical, 1 923.54 +/- 72.35 microm diameter with several corionic filaments, and are striated. During the first 48 h the embryo developed cephalic vesicle, miomers, and a heart located on the external body surface, beating strongly and circulating colorless blood which became pigmented red later. Before hatching, the larva developed kidney, gut tract, liver and biliar vesicle, pectoral fins, four pairs of gill arches and the mouth. The larva hatched at 114 h, the body was torpedo-shaped, yellow-green, with several dendriform melanophores; the pelvic fin was observed 72 h post hatching. At 240 hours the metamorphoses was completed. When the larvae hatched they could ingest Artemia metanauplii. PMID:19419056

  8. The effect of structural and rheological properties on blood flow distributions in capillary networks

    NASA Astrophysics Data System (ADS)

    Goldman, Daniel

    2001-11-01

    In various tissues microvascular structure, both geometric and topological, has been shown to be an important determinant of microcirculatory hemodynamics. In addition, blood rheology affects flow and hematocrit distributions in the microcirculation. Here we study steady-state hemodynamics in capillary networks modeled on the three-dimensional structure of the hamster cheek pouch retractor muscle. Capillary diameter is fixed while other structural properties are varied and an ensemble of similar random networks is generated for each parameter set. Using an experimentally derived two-phase continuum model for the flow of blood plasma and red cells, we investigate the effects of network size and topology on blood flow distributions and their variability. We also use typical capillary network structures to examine the importance of rheological effects under varying conditions. Our results indicate the relative importance of microvascular structure and blood rheology in determining the hemodynamic properties of capillary networks in striated muscle.

  9. Attention Decreases Phase-Amplitude Coupling, Enhancing Stimulus Discriminability in Cortical Area MT

    PubMed Central

    Esghaei, Moein; Daliri, Mohammad Reza; Treue, Stefan

    2015-01-01

    Local field potentials (LFPs) in cortex reflect synchronous fluctuations in the synaptic activity of local populations of neurons. The power of high frequency (>30 Hz) oscillations in LFPs is locked to the phase of low frequency (<30 Hz) oscillations, an effect known as phase-amplitude coupling (PAC). While PAC has been observed in a variety of cortical regions and animal models, its functional role particularly in primate visual cortex is largely unknown. Here, we document PAC for LFPs recorded from extra-striate area MT of macaque monkeys, an area specialized for the processing of visual motion. We further show that directing spatial attention into the receptive field of MT neurons decreases the coupling between the low frequency phase and high frequency power of LFPs. This attentional suppression of PAC increases neuronal discriminability for attended visual stimuli. Therefore, we hypothesize that visual cortex uses PAC to regulate inter-neuronal correlations and thereby enhances the coding of relevant stimuli. PMID:26733820

  10. Exploring the physiological correlates of chronic mild traumatic brain injury symptoms

    PubMed Central

    Astafiev, Serguei V.; Zinn, Kristina L.; Shulman, Gordon L.; Corbetta, Maurizio

    2016-01-01

    We report on the results of a multimodal imaging study involving behavioral assessments, evoked and resting-state BOLD fMRI, and DTI in chronic mTBI subjects. We found that larger task-evoked BOLD activity in the MT+/LO region in extra-striate visual cortex correlated with mTBI and PTSD symptoms, especially light sensitivity. Moreover, higher FA values near the left optic radiation (OR) were associated with both light sensitivity and higher BOLD activity in the MT+/LO region. The MT+/LO region was localized as a region of abnormal functional connectivity with central white matter regions previously found to have abnormal physiological signals during visual eye movement tracking (Astafiev et al., 2015). We conclude that mTBI symptoms and light sensitivity may be related to excessive responsiveness of visual cortex to sensory stimuli. This abnormal sensitivity may be related to chronic remodeling of white matter visual pathways acutely injured. PMID:26909324

  11. Rhabdomyomatous mesenchymal hamartoma presenting as a skin tag in the sternoclavicular area.

    PubMed

    Solis-Coria, Araceli; Vargas-González, Roberto; Sotelo-Avila, Cirilo

    2007-01-01

    Rhabdomyomatous mesenchymal hamartoma (RMH) is a rare congenital lesion of the dermis and subdermis. It has been described predominantly in newborns, with 30 cases reported in the English literature. Typically, it appears as a skin tag, papule, nodule or a mass involving the face or sternal notch. A 28-day-old girl presented with a 1.4 x 0.8 cm soft skin tag in the right sternoclavicular area. Physical examination revealed no congenital anomalies. A shaved biopsy showed that the core of the lesion contained striated muscle fibers mixed with hair follicles and sebaceous and eccrine glands. Thin epidermis lined the outside of the tag. We report a patient with a RMH in a site not previously reported and discuss the differential diagnosis. PMID:18158576

  12. Titin, a Central Mediator for Hypertrophic Signaling, Exercise-Induced Mechanosignaling and Skeletal Muscle Remodeling

    PubMed Central

    Krüger, Martina; Kötter, Sebastian

    2016-01-01

    Titin is a giant scaffold protein with multiple functions in striated muscle physiology. Due to the elastic I-band domains and the filament-like integration in the half-sarcomere titin is an important factor for sarcomere assembly and serves as an adaptable molecular spring that determines myofilament distensibility. Protein-interactions e.g., with muscle ankyrin repeat proteins or muscle LIM-protein link titin to hypertrophic signaling and via p62 and Muscle Ring Finger proteins to mechanisms that control protein quality control. This review summarizes our current knowledge on titin as a central node for exercise-induced mechanosignaling and remodeling and further highlights the pathophysiological implications. PMID:26973541

  13. The polyvagal theory: new insights into adaptive reactions of the autonomic nervous system.

    PubMed

    Porges, Stephen W

    2009-04-01

    The polyvagal theory describes an autonomic nervous system that is influenced by the central nervous system, sensitive to afferent influences, characterized by an adaptive reactivity dependent on the phylogeny of the neural circuits, and interactive with source nuclei in the brainstem regulating the striated muscles of the face and head. The theory is dependent on accumulated knowledge describing the phylogenetic transitions in the vertebrate autonomic nervous system. Its specific focus is on the phylogenetic shift between reptiles and mammals that resulted in specific changes to the vagal pathways regulating the heart. As the source nuclei of the primary vagal efferent pathways regulating the heart shifted from the dorsal motor nucleus of the vagus in reptiles to the nucleus ambiguus in mammals, a face-heart connection evolved with emergent properties of a social engagement system that would enable social interactions to regulate visceral state. PMID:19376991

  14. Practical application of color Doppler ultrasonography in patients with ejaculatory dysfunction.

    PubMed

    Hara, Ryoei; Nagai, Atsushi; Fujii, Tomohiro; Fukumoto, Kazuhiko; Ohira, Shin; Jo, Yoshimasa; Yokoyama, Teruhiko; Miyaji, Yoshiyuki

    2015-06-01

    We describe two cases in which dynamic analysis of ejaculation using color Doppler ultrasonography was useful in diagnosis of ejaculatory dysfunction and planning of therapy. The first patient was a 32-year-old man with a diagnosis of retrograde ejaculation. A bladder neck collagen injection was carried out, as the main cause was thought to be the bladder neck remaining open during ejaculation. The patient had antegrade ejaculation 1 week later. The second patient was a 48-year-old man with a diagnosis of anorgasmia accompanied by decreased seminal emission and insufficient function of the rhythmic pelvic striated muscles. The patient was prescribed etilefrine hydrochloride 15 mg/day. The symptom improved 2 weeks after starting this drug. These cases suggest that the use of color Doppler ultrasonography during ejaculation can improve the understanding of ejaculatory dysfunction and therapy for this condition. PMID:25808696

  15. Water-tunnel experiments on an oscillating airfoil at RE equals 21,000

    NASA Technical Reports Server (NTRS)

    Mcalister, K. W.; Carr, L. W.

    1978-01-01

    Flow visualization experiments were performed in a water tunnel on a modified NACA 0012 airfoil undergoing large amplitude harmonic oscillations in pitch. Hydrogen bubbles were used to: (1) create a conveniently striated and well preserved set of inviscid flow markers; and (2) to expose the succession of events occurring within the viscous domain during the onset of dynamic stall. Unsteady effects were shown to have an important influence on the progression of flow reversal along the airfoil surface prior to stall. A region of reversed flow underlying a free shear layer was found to momentarily exist over the entire upper surface without any appreciable disturbance of the viscous-inviscid boundary. A flow protuberance was observed to develop near the leading edge, while minor vortices evolve from an expanding instability of the free shear layer over the rear portion of the airfoil. The complete breakdown of this shear layer culminates in the successive formation of two dominant vortices.

  16. Photo essay. MRI and positron emission tomography findings in Heidenhain variant Creutzfeldt-Jakob disease.

    PubMed

    Prasad, Sashank; Lee, Edward B; Woo, John H; Alavi, Abass; Galetta, Steven L

    2010-09-01

    The typical presentation of Heidenhain variant Creutzfeldt-Jakob disease (CJD) is a rapidly progressive visual loss in the setting of a relatively normal ophthalmologic examination. At presentation, patients with this uniformly fatal illness frequently demonstrate only minor cortical abnormalities on MRI. Here, we document the clinical presentation and imaging results of a patient with Heidenhain variant CJD in whom abnormalities on positron emission tomographic imaging were more evident than changes on MRI. These changes were present in striate cortex and visual association areas, providing clinical-anatomical correlation with our patient's visual deficits. Nuclear imaging provides a considerably more sensitive measure of neural dysfunction early in the course of this disease. PMID:20581692

  17. A Heidenhain variant of Creutzfeldt-Jakob disease: forensic implication.

    PubMed

    Rizzo, M; Bruni, A; Barberio, C; Magro, G; Foncin, J F

    2004-12-01

    To investigate whether typical clinical, diagnostic and neuropathological findings can be identified in a patient with a postmortem diagnosis of a Heidenhain variant of Creutzfeldt-Jakob disease (CJD). We report a new case of CJD in a rare variant. A man admitted to hospital with cefalea and vision disorder. Clinical and neurological examination showed headache, vision reduction, psychomotor anxiety and progressive torpor. The patient died 4 h after admission to hospital. The autopsy findings included marked encephalic vascular congestion. Hystoneurology examination showed no macroscopic anomaly. Microscopy findings included neuronal loss, gliosis in striate area with arachnoid cells and cerebellum microspongiosis. Creutzfeldt-Jakob disease is a rare neurodegenerative human disorder. The prion hypothesis as an explanatory model is currently favoured by majority of researchers. A disease course described by Heidenhain including the leading symptoms of a visual disorder and rapid progression. This report emphasize the multidisciplinary role (forensic, neurogenetic and neurohistologic) for diagnosis and to standardize a protocol to investigate. PMID:15639587

  18. [Effect of weightlessness on the indices of brain development (the results of pregnant rats being on the Kosmos-1514 biosatellite and research on the subsequent development of their progeny on Earth)].

    PubMed

    Olenev, S N; Danilov, A R; Kriuchkova, T A; Sorokina, L M; Krasnov, I B

    1987-09-01

    Beginning from the 13th day of pregnancy the rats were under conditions of weightlessness of spaceflight for 6 days. After landing in 18-day-old fetuses the state of their brain development is investigated comparing to that in control animals, that are on the Earth. As demonstrates analysis of a number of morphological processes: reproduction, migration, neuronal differentiation, growth of processes, establishment of nervous connections, neuroglial interconnections and vascularization--all they under conditions of weightlessness develop rather fully. Certain deviations in vascularization (as examples the medulla oblongata and the striated tuber are taken) are observed--the amount of vessels is greater and they are thinner--and changes in migration rate of cells is demonstrated by the example of the cortical plate formation. These changes are quickly levelled during their subsequent development on the Earth. PMID:3426406

  19. Electrolichas circumbalticus gen. et sp. nov. (Coleoptera: Byrrhoidea: Ptilodactylidae) from Baltic amber, the first anchytarsine toed-winged beetle described from Europe.

    PubMed

    Alekseev, Vitalii I; Jäch, Manfred A

    2016-01-01

    A new genus and species of Ptilodactylidae, Electrolichas circumbalticus gen. et sp. nov., the first fossil representative of the subfamily Anchytarsinae, is described from Baltic amber. This Eocene beetle can be distinguished from the extant genera of Anchytarsinae by the combination of the following characters: labrum transverse, terminal segment of maxillary palps cylindrical, antennae with non-articulated rami, basal pronotal margin only very finely crenulate, lacking a median denticle, anterior margin of scutellum not excised medially, elytra not striate, tarsi not pseudotetramerous, proportional lengths: 1.5: 1.2: 1.2: 1.1: 1.5, flashy pads on apex of first tarsomere as well as on tarsomeres 2-4. A list of the extant species of Anchytarsinae is provided. Both hitherto described fossil ptilodactylid genera are briefly discussed. PMID:27395736

  20. The STARS signaling pathway: a key regulator of skeletal muscle function.

    PubMed

    Lamon, Séverine; Wallace, Marita A; Russell, Aaron P

    2014-09-01

    During the last decade, the striated muscle activator of Rho signaling (STARS), a muscle-specific protein, has been proposed to play an increasingly important role in skeletal muscle growth, metabolism, regeneration and stress adaptation. STARS influences actin dynamics and, as a consequence, regulates the myocardin-related transcription factor A/serum response factor (MRTF-A/SRF) transcriptional program, a well-known pathway controlling skeletal muscle development and function. Muscle-specific stress conditions, such as exercise, positively regulates, while disuse and degenerative muscle diseases are associated with a downregulation of STARS and its downstream partners, suggesting a pivotal role for STARS in skeletal muscle health. This review provides a comprehensive overview of the known role and regulation of STARS and the members of its signaling pathway, RhoA, MRTF-A and SRF, in skeletal muscle. PMID:24557714

  1. Recent progress in the topology, structure, and oligomerization of caveolin: a building block of caveolae.

    PubMed

    Root, Kyle T; Plucinsky, Sarah M; Glover, Kerney Jebrell

    2015-01-01

    Caveolae are cholesterol-rich plasma membrane invaginations that are found in a plethora of cell types. They play many roles including signal transduction, endocytosis, and mechanoprotection. The most critical protein in caveolae is the integral membrane protein, caveolin, which has been shown to be necessary for caveolae formation, and governs the major functions attributed to caveolae. Caveolin is postulated to act as a scaffold in the high molecular weight striated coat that surrounds the caveolar bulb, stabilizing it. Caveolin interacts, both directly and indirectly, with a large number of signaling molecules, and presides over the endocytosis of molecular cargo by caveolae. However, many of the key biophysical aspects of the caveolin protein, its structure, topology, and oligomeric behavior, are just beginning to come to light. Herein is an up-to-date summary and critique of the progress that has been made in understanding caveolin on a molecular and atomic level. PMID:26015287

  2. A new Lower Triassic ichthyopterygian assemblage from Fossil Hill, Nevada

    PubMed Central

    Motani, Ryosuke; Embree, Patrick; Orchard, Michael J.

    2016-01-01

    We report a new ichthyopterygian assemblage from Lower Triassic horizons of the Prida Formation at Fossil Hill in central Nevada. Although fragmentary, the specimens collected so far document a diverse fauna. One partial jaw exhibits isodont dentition with blunt tipped, mesiodistally compressed crowns and striated enamel. These features are shared with the Early Triassic genus Utatsusaurus known from coeval deposits in Japan and British Columbia. An additional specimen exhibits a different dentition characterized by relatively small, rounded posterior teeth resembling other Early Triassic ichthyopterygians, particularly Grippia. This Nevada assemblage marks a southward latitudinal extension for Early Triassic ichthyopterygians along the eastern margin of Panthalassa and indicates repeated trans-hemispheric dispersal events in Early Triassic ichthyopterygians. PMID:26855868

  3. Pseudotumoral hemicerebellitis as a mimicker of Lhermitte-Duclos disease in children: does neuroimaging help to differentiate them?

    PubMed

    Bosemani, Thangamadhan; Steinlin, Maja; Toelle, Sandra P; Beck, Jürgen; Boltshauser, Eugen; Huisman, Thierry A G M; Poretti, Andrea

    2016-05-01

    The clinical presentation and neuroimaging findings of children with pseudotumoral hemicerebellitis (PTHC) and Lhermitte-Duclos disease (LDD) may be very similar. The differentiation between these entities, however, is important because their management and prognosis are different. We report on three children with PTHC. For all three children, in the acute situation, the differentiation between PTHC and LDD was challenging. A review of the literature shows that a detailed evaluation of conventional and neuroimaging data may help to differentiate between these two entities. A striated folial pattern, brainstem involvement, and prominent veins surrounding the thickened cerebellar foliae on susceptibility weighted imaging favor LDD, while post-contrast enhancement and an increased choline peak on (1)H-Magnetic resonance spectroscopy suggest PTHC. PMID:26649682

  4. Pulmonary choriostoma in a case of tuberous sclerosis complex

    PubMed Central

    Spalgais, S; Gothi, D; Verma, AK

    2015-01-01

    A 52 years old lady was diagnosed to have Tuberous Sclerosis Complex (TSC) on the basis of 2 major and one minor criterion. She had family history of similar complaints in her sister and two sons. There was involvement of kidney in the form of angiomyolipoma, skin in the form of facial angiofibroma and teeth with a dental pit. She had an unusual lung involvement in the form of multiple small choristomas. Choristoma was diagnosed on transbronchial lung biopsy and was present in the form of disorganised striated muscles. The reported pulmonary manifestations of TCS i.e. lymphangioleiomyomatosis (LAM) and multifocal micronodular pneumocyte hyperplasia (MMPH) are types of hamartomas. Hamartomas and choristomas are both types of disorganized tissue. ‘Choristoma’of lung in TSC however is not reported. Clinopathological correlation of pulmonary hamartoma and choristoma, and treatment in TSC has been discussed. PMID:26119439

  5. A photo-defined membrane for precisely patterned cellular and microparticle arrays

    NASA Astrophysics Data System (ADS)

    McPherson, A. L.; Walker, G. M.

    2012-03-01

    The ability to pattern particles in well-defined arrays enhances microfluidic devices. A low-fluorescence optically transparent photo-curable resist (1002F) was characterized for use as a mechanical sieve in a microfluidic chip. Films of thickness 10 μm and 25 μm were created containing pores 6-10 μm in diameter with pitches ranging from 5-300 μm. The uniform photo-defined pores had diameters with standard deviations of 3%. Integrated with microfluidic devices, the films were used to trap polystyrene microspheres, and in a different experiment, MCF7 human epithelial adenocarcinoma cells (ATCC HTB-22). A mechanical sieve was used to trap two types of fluorescent particles and, separately MCF7 cells with NIH/3T3 murine fibroblast cells (ATCC CRL-1658) as a proof-of-concept for striated cellular co-culture.

  6. [Myasthenia gravis].

    PubMed

    Schodrowski, J; Seipelt, M; Adibi-Sedeh, I; Eienbröker, C; Tackenberg, B

    2016-04-01

    Myasthenia gravis is an autoimmune disease, which leads to load-dependent weakness of voluntary skeletal muscles with recovery of function after resting. The disease is caused by autoantibodies directed against the postsynaptic nicotinic acetylcholine receptors (AChR) leading to a reduction of neuromuscular transmission. Muscles and nerves are not affected. Disorders of the thymus play a role in the pathogenesis of AChR antibody-positive myasthenia. The clinical symptoms include exercise-induced fatigue either of the ocular muscles alone (ocular myasthenia) or striated skeletal muscle and the ocular, facial and bulbar musculature (generalized myasthenia). Treatment of myasthenia gravis involves administration of acetylcholine esterase inhibitors and immunosuppressive drugs. A myasthenic crisis is characterized by life-threatening complications with severe weakness, swallowing difficulties and respiratory failure, which requires intensive care treatment. PMID:27000188

  7. Histopathological changes in the placentas and fetuses of mice infected with Trypanosoma cruzi isolated from the Myotis nigricans nigricans bat.

    PubMed

    Badra, E S; Sala, M A; Lopes, R A; Prado, J C; Albuquerque, S; Zucoloto, S; Carraro-Abrahão, A A

    2008-01-01

    Histopathological changes and placental transmission were studied in the late stages of pregnancy in mice infected with a strain of Trypanosoma cruzi, isolated from a Myotis nigricans nigricans bat. Large amastigote nests were observed in uterine muscles, as well as in decidual and endothelial placental cells. In addition, persistent coagulative and fibrotic vascular degeneration was observed. Large amastigote burdens were found in giant cells, spongioblasts and endothelial cells within the labyrinthine layer. Transplacental transmission was confirmed in 30% of the fetuses examined, in which amastigote nests were seen only in striated muscle. During the acute phase, intrauterine development was impaired as the result of parasitic invasion of the placenta, and fetal mortality rose to 10%. PMID:18640685

  8. Carboxymethyl functionalization of amylopectin and its evaluation as a nanometric drug carrier.

    PubMed

    Thakur, Kanika; Ahuja, Munish; Kumar, Ashok

    2013-11-01

    Carboxymethylation of amylopectin was accomplished by reacting it with monochloroacetic acid. The results of characterization study confirmed the carboxymethyl functionalization with degree of substitution of 1.25. Carboxymethyl amylopectin was found to be slightly more crystalline, appearing morphologically as polyhedral flakes with striated surface. Further, carboxymethylation of amylopectin modified its compression characteristic from fragmentary to plastic. Interaction of carboxymethyl amylopectin (0.001-0.005%, w/v) with chitosan (0.05-0.075% w/v) using ibuprofen (0.05%, w/v) as a model drug provided polyelectrolyte nanoparticles of size 182.7-353.3 nm and 75-92% drug entrapment. The polyelectrolyte nanoparticles showed a sustained release of drug following zero-order kinetics with mechanism of release being combination of matrix erosion and diffusion through the matrix. PMID:23973491

  9. First isolation of Sarcocystis hominis from cattle in Japan.

    PubMed

    Saito, M; Shibata, Y; Kubo, M; Sakakibara, I; Yamada, A; Itagaki, H

    1999-03-01

    Sarcocystis hominis was first isolated from slaughtered cattle raised in Japan. Cysts were 1,220-4,460 x 80-384 microns in size and their wall was 3 to 6 microns thick and appeared radially striated in the histopathological sections because of the presence of palisade-like villar protrusions on the surface. The protrusions were 3.1-4.3 x 0.7-1.1 microns in size and had many microtubules in the core. Two cynomolgus monkeys, Macaca fascicularis, fed with the Sarcocystis cysts began to pass sporocysts, which measured a size of 14.3-15 x 9.5-10 microns, in the feces 10 days after ingestion. PMID:10331210

  10. The Structure and Regulation of Human Muscle α-Actinin

    PubMed Central

    Ribeiro, Euripedes de Almeida; Pinotsis, Nikos; Ghisleni, Andrea; Salmazo, Anita; Konarev, Petr V.; Kostan, Julius; Sjöblom, Björn; Schreiner, Claudia; Polyansky, Anton A.; Gkougkoulia, Eirini A.; Holt, Mark R.; Aachmann, Finn L.; Žagrović, Bojan; Bordignon, Enrica; Pirker, Katharina F.; Svergun, Dmitri I.; Gautel, Mathias; Djinović-Carugo, Kristina

    2014-01-01

    Summary The spectrin superfamily of proteins plays key roles in assembling the actin cytoskeleton in various cell types, crosslinks actin filaments, and acts as scaffolds for the assembly of large protein complexes involved in structural integrity and mechanosensation, as well as cell signaling. α-actinins in particular are the major actin crosslinkers in muscle Z-disks, focal adhesions, and actin stress fibers. We report a complete high-resolution structure of the 200 kDa α-actinin-2 dimer from striated muscle and explore its functional implications on the biochemical and cellular level. The structure provides insight into the phosphoinositide-based mechanism controlling its interaction with sarcomeric proteins such as titin, lays a foundation for studying the impact of pathogenic mutations at molecular resolution, and is likely to be broadly relevant for the regulation of spectrin-like proteins. PMID:25433700

  11. Finding the sweet spot: Assembly and Glycosylation of the Dystrophin-Associated Glycoprotein Complex

    PubMed Central

    Townsend, DeWayne

    2014-01-01

    The dystrophin-associated glycoprotein complex (DGC) is a collection of glycoproteins that are essential for the normal function of striated muscle and many other tissues. Recent genetic studies have implicated the components of this complex in over a dozen forms of muscular dystrophy. Furthermore, disruption of the DGC has been implicated in many forms of acquired disease. This review aims to summarize the current state of knowledge regarding the processing and assembly of dystrophin associated proteins with a focus primarily on the dystroglycan heterodimer and the sarcoglycan complex. These proteins form the transmembrane portion of the DGC and undergo a complex multi-step processing with proteolytic cleavage, differential assembly, and both N- and O-glycosylation. The enzymes responsible for this processing and a model describing the sequence and subcellular localization of these events are discussed. PMID:25125182

  12. Hereditary palmoplantar keratoderma "clinical and genetic differential diagnosis".

    PubMed

    Sakiyama, Tomo; Kubo, Akiharu

    2016-03-01

    Hereditary palmoplantar keratoderma (PPK) is a heterogeneous group of disorders characterized by hyperkeratosis of the palm and the sole skin. Hereditary PPK are divided into four groups--diffuse, focal, striate and punctate PPK--according to the clinical patterns of the hyperkeratotic lesions. Each group includes simple PPK, without associated features, and PPK with associated features, such as involvement of nails, teeth and other organs. PPK have been classified by a clinically based descriptive system. In recent years, many causative genes of PPK have been identified, which has confirmed and/or rearranged the traditional classifications. It is now important to diagnose PPK by a combination of the traditional morphological classification and genetic testing. In this review, we focus on PPK without associated features and introduce their morphological features, genetic backgrounds and new findings from the last decade. PMID:26945534

  13. Ozz-E3 ubiquitin ligase targets sarcomeric embryonic myosin heavy chain during muscle development.

    PubMed

    Campos, Yvan; Qiu, Xiaohui; Zanoteli, Edmar; Moshiach, Simon; Vergani, Naja; Bongiovanni, Antonella; Harris, A John; d'Azzo, Alessandra

    2010-01-01

    Muscle contractile proteins are expressed as a series of developmental isoforms that are in constant dynamic remodeling during embryogenesis, but how obsolete molecules are recognized and removed is not known. Ozz is a developmentally regulated protein that functions as the adaptor component of a RING-type ubiquitin ligase complex specific to striated muscle. Ozz(-/-) mutants exhibit defects in myofibrillogenesis and myofiber differentiation. Here we show that Ozz targets the rod portion of embryonic myosin heavy chain and preferentially recognizes the sarcomeric rather than the soluble pool of myosin. We present evidence that Ozz binding to the embryonic myosin isoform within sarcomeric thick filaments marks it for ubiquitination and proteolytic degradation, allowing its replacement with neonatal or adult isoforms. This unique function positions Ozz within a system that facilitates sarcomeric myosin remodeling during muscle maturation and regeneration. Our findings identify Ozz-E3 as the ubiquitin ligase complex that interacts with and regulates myosin within its fully assembled cytoskeletal structure. PMID:20352047

  14. Preparation of alginate-chitosan fibers with potential biomedical applications.

    PubMed

    Sibaja, Bernal; Culbertson, Edward; Marshall, Patrick; Boy, Ramiz; Broughton, Roy M; Solano, Alejandro Aguilar; Esquivel, Marianelly; Parker, Jennifer; De La Fuente, Leonardo; Auad, Maria L

    2015-12-10

    The preparation of alginate-chitosan fibers, through wet spinning technique, as well as the study of their properties as a function of chitosan's molecular weight and retention time in the coagulation bath, is presented and discussed in this work. Scanning electron microscopy (SEM) revealed that the fibers presented irregular and rough surfaces, with a grooved and heavily striated morphology distributed throughout the structure. Dynamic mechanical analysis (DMA) showed that, with the exception of elongation at break, the incorporation of chitosan into the fibers improved their tensile properties. The in vitro release profile of sulfathiazole as a function of chitosan's molecular weight indicated that the fibers are viable carriers of drugs. Kinetic models showed that the release of the model drug is first-order, and the release mechanism is governed by the Korsmeyer-Peppas model. Likewise, fibers loaded with sulfathiazole showed excellent inhibition of Escherichia coli growth after an incubation time of 24h at 37 °C. PMID:26428163

  15. Probing the 3D structure of cornea-like collagen liquid crystals with polarization-resolved SHG microscopy.

    PubMed

    Teulon, Claire; Tidu, Aurélien; Portier, François; Mosser, Gervaise; Schanne-Klein, Marie-Claire

    2016-07-11

    This work aims at characterizing the three-dimensional organization of liquid crystals composed of collagen, in order to determine the physico-chemical conditions leading to highly organized structures found in biological tissues such as cornea. To that end, we use second-harmonic generation (SHG) microscopy, since aligned collagen structures have been shown to exhibit intrinsic SHG signals. We combine polarization-resolved SHG experiments (P-SHG) with the theoretical derivation of the SHG signal of collagen molecules tilted with respect to the focal plane. Our P-SHG images exhibit striated patterns with variable contrast, as expected from our analytical and numerical calculations for plywood-like nematic structures similar to the ones found in the cornea. This study demonstrates the benefits of P-SHG microscopy for in situ characterization of highly organized biopolymers at micrometer scale, and the unique sensitivity of this nonlinear optical technique to the orientation of collagen molecules. PMID:27410876

  16. Fructose-bisphosphate aldolase a is a potential metastasis-associated marker of lung squamous cell carcinoma and promotes lung cell tumorigenesis and migration.

    PubMed

    Du, Sha; Guan, Zhuzhu; Hao, Lihong; Song, Yang; Wang, Lan; Gong, Linlin; Liu, Lu; Qi, Xiaoyu; Hou, Zhaoyuan; Shao, Shujuan

    2014-01-01

    Fructose-bisphosphate aldolase A (ALDOA) is a key enzyme in glycolysis and is responsible for catalyzing the reversible conversion of fructose-1,6-bisphosphate to glyceraldehydes-3-phosphate and dihydroxyacetone phosphate. ALDOA contributes to various cellular functions such as muscle maintenance, regulation of cell shape and mobility, striated muscle contraction, actin filament organization and ATP biosynthetic process. Here, we reported that ALDOA is a highly expressed in lung squamous cell carcinoma (LSCC) and its expression level is correlated with LSCC metastasis, grades, differentiation status and poor prognosis. Depletion of ALDOA expression in the lung squamous carcinoma NCI-H520 cells reduces the capabilities of cell motility and tumorigenesis. These data suggest that ALDOA could be a potential marker for LSCC metastasis and a therapeutic target for drug development. PMID:24465716

  17. Fructose-Bisphosphate Aldolase A Is a Potential Metastasis-Associated Marker of Lung Squamous Cell Carcinoma and Promotes Lung Cell Tumorigenesis and Migration

    PubMed Central

    Hao, Lihong; Song, Yang; Wang, Lan; Gong, Linlin; Liu, Lu; Qi, Xiaoyu; Hou, Zhaoyuan; Shao, Shujuan

    2014-01-01

    Fructose-bisphosphate aldolase A (ALDOA) is a key enzyme in glycolysis and is responsible for catalyzing the reversible conversion of fructose-1,6-bisphosphate to glyceraldehydes-3-phosphate and dihydroxyacetone phosphate. ALDOA contributes to various cellular functions such as muscle maintenance, regulation of cell shape and mobility, striated muscle contraction, actin filament organization and ATP biosynthetic process. Here, we reported that ALDOA is a highly expressed in lung squamous cell carcinoma (LSCC) and its expression level is correlated with LSCC metastasis, grades, differentiation status and poor prognosis. Depletion of ALDOA expression in the lung squamous carcinoma NCI-H520 cells reduces the capabilities of cell motility and tumorigenesis. These data suggest that ALDOA could be a potential marker for LSCC metastasis and a therapeutic target for drug development. PMID:24465716

  18. Normal anatomic relationship between urethral sphincter complex and zones of prostrate in young Chinese males on MRI

    PubMed Central

    Wang, Xiangdong; Liu, Tieyan; Zhao, Jing; Sun, Jingyi; Chen, Yuefeng; Sun, Pengyu; Wang, Xuesong; Liu, Sheng

    2015-01-01

    Objective In this research, the normal anatomic relationship between urethral sphincter complex and zones of prostrate in young Chinese males has been studied. Methods: The sagittal, coronal, and axial T2-weighted non-fat suppressed fast spin-echo images of pelvic cavities of 86 Chinese young males were studied. Result: Urethral sphincter complex threaded through the prostate and divided it into 2 parts: transition zone (TZ), periurethral glands internal to the urethral sphincter and peripheral zone (PZ), central zone (CZ), anterior fibromuscular stroma (AFS) zone external to the urethral sphincter. The length of urethral striated sphincter is 12.26-20.94 mm (mean 16.59 mm) at membranous urethra. Conclusions: In this paper, we summarized the normal anatomic relationship between urethral sphincter complex and zones of prostrate in young Chinese males with no urinary control problems. PMID:26629244

  19. Pathology of eyelid tumors.

    PubMed

    Pe'er, Jacob

    2016-03-01

    The eyelids are composed of four layers: skin and subcutaneous tissue including its adnexa, striated muscle, tarsus with the meibomian glands, and the palpebral conjunctiva. Benign and malignant tumors can arise from each of the eyelid layers. Most eyelid tumors are of cutaneous origin, mostly epidermal, which can be divided into epithelial and melanocytic tumors. Benign epithelial lesions, cystic lesions, and benign melanocytic lesions are very common. The most common malignant eyelid tumors are basal cell carcinoma in Caucasians and sebaceous gland carcinoma in Asians. Adnexal and stromal tumors are less frequent. The present review describes the more important eyelid tumors according to the following groups: Benign and malignant epithelial tumors, benign and malignant melanocytic tumors, benign and malignant adnexal tumors, stromal eyelid tumors, lymphoproliferative and metastatic tumors, other rare eyelid tumors, and inflammatory and infections lesions that simulate neoplasms. PMID:27146927

  20. Elasticity, unexpected contractility and the identification of actin and myosin in lobster arteries.

    PubMed

    Wilkens, J L; Cavey, M J; Shovkivska, I; Zhang, M L; ter Keurs, H E D J

    2008-03-01

    Lobster arteries, which exhibit non-uniform elasticity when stretched, have a trilaminar organization. The inner layer is an elastic connective tissue and the outer layer is a collagenous connective tissue; the middle layer of an artery is an aggregation of cells containing microfilaments. Arterial cells possess actin, myosin and tropomyosin. Except for the dorsal abdominal artery, striated muscle cells are not evident in the walls of any of the vessels. The neurotransmitter glutamic acid and the neurohormone proctolin elicit slow circumferential contractions in all of the arteries leaving the lobster heart. Only the dorsal abdominal artery contracts when stimulated electrically. Longitudinal strips of the arteries do not respond to either drugs or electrical stimulation. Arterial contraction will have profound effects on resistance to blood flow and may be an important component of the control mechanisms regulating blood distribution. PMID:18281339

  1. Muscle intermediate filaments and their links to membranes and membranous organelles

    SciTech Connect

    Capetanaki, Yassemi . E-mail: ycapetanaki@bioacademy.gr; Bloch, Robert J.; Kouloumenta, Asimina; Mavroidis, Manolis; Psarras, Stelios

    2007-06-10

    Intermediate filaments (IFs) play a key role in the integration of structure and function of striated muscle, primarily by mediating mechanochemical links between the contractile apparatus and mitochondria, myonuclei, the sarcolemma and potentially the vesicle trafficking apparatus. Linkage of all these membranous structures to the contractile apparatus, mainly through the Z-disks, supports the integration and coordination of growth and energy demands of the working myocyte, not only with force transmission, but also with de novo gene expression, energy production and efficient protein and lipid trafficking and targeting. Desmin, the most abundant and intensively studied muscle intermediate filament protein, is linked to proper costamere organization, myoblast and stem cell fusion and differentiation, nuclear shape and positioning, as well as mitochondrial shape, structure, positioning and function. Similar links have been established for lysosomes and lysosome-related organelles, consistent with the presence of widespread links between IFs and membranous structures and the regulation of their fusion, morphology and stabilization necessary for cell survival.

  2. Microscopy of the echidna sublingual glands.

    PubMed

    Krause, William J

    2011-10-01

    The secretory units and duct system of the echidna sublingual glands exhibit subtle architectural modifications to accommodate the viscous secretion produced by these glands. The glands are compound tubular glands, the secretory units of which are elongate with open lumina and consist only of mucous cells. Closely packed spindle-shaped myoepithelial cells invest the secretory units, but are absent around the ducts. The branched secretory tubules open into an abbreviated duct system characterized by wide lumina. Striated ducts normally associated with the second portion of the intralobular duct system are absent. The duct system shows the most obvious modification of general salivary gland architecture presumably to accommodate the viscous secretion propelled from the secretory units by surrounding myoepithelial cells. PMID:21671992

  3. Pathology of eyelid tumors

    PubMed Central

    Pe’er, Jacob

    2016-01-01

    The eyelids are composed of four layers: skin and subcutaneous tissue including its adnexa, striated muscle, tarsus with the meibomian glands, and the palpebral conjunctiva. Benign and malignant tumors can arise from each of the eyelid layers. Most eyelid tumors are of cutaneous origin, mostly epidermal, which can be divided into epithelial and melanocytic tumors. Benign epithelial lesions, cystic lesions, and benign melanocytic lesions are very common. The most common malignant eyelid tumors are basal cell carcinoma in Caucasians and sebaceous gland carcinoma in Asians. Adnexal and stromal tumors are less frequent. The present review describes the more important eyelid tumors according to the following groups: Benign and malignant epithelial tumors, benign and malignant melanocytic tumors, benign and malignant adnexal tumors, stromal eyelid tumors, lymphoproliferative and metastatic tumors, other rare eyelid tumors, and inflammatory and infections lesions that simulate neoplasms. PMID:27146927

  4. Investigation of passive atmospheric sounding using millimeter and submillimeter wavelength channels

    NASA Technical Reports Server (NTRS)

    Gasiewski, Albin J.

    1993-01-01

    Presented in this study are the results of controlled partially polarimetric measurements of thermal emission at 91.65 GHz from a striated water surface as corroborated by a geometrical optics radiative model. The measurements were obtained outdoors using a precision polarimetric radiometer which directly measured the first three modified Stokes' parameters. Significant variations in these parameters as a function of azimuthal water wave angle were found, with peak-to-peak variations in T(sub u) of up to approximately 10 K. The measurements are well corroborated by the GO model over a range of observations angles from near nadir up to approximately 65 degrees from nadir. The model incorporates both multiple scattering and a realistic downwelling background brightness field.

  5. Centromere structure and chromosome number in mitosis of the colourless phytoflagellate Polytoma papillatum (Chlorophyceae, Volvocales, Chlamydomonadaceae).

    PubMed

    Wolf, K W

    1995-12-01

    Centromere structure is described in mitosis of the unicellular biflagellate alga Polytoma papillatum using transmission electron microscopy. The kinetochores are five-layered elements at the poleward surface of the chromosomes. The five layers consist of three dense plates interspersed by two transparent zones. The polemost dense layer serves as the attachment site for kinetochore microtubules and the innermost dense layer is intimately associated with the chromatin. The five-layered organization of the kinetochore in the alga is unusual. In animals, three-layered kinetochores are the rule. This type has also been found in some algae, while higher plants do not possess striated kinetochores. An attempt was made to determine the chromosome number of P. papillatum. Individual chromosomes could not be recognized with confidence, since there were numerous lateral contacts between the chromosomes throughout mitosis. An alternative approach, however, was successful. Counting the kinetochores in serial sections through mitotic metaphase and anaphase plates revealed a number of 15 chromosomes. PMID:18470243

  6. At the Start of the Sarcomere: A Previously Unrecognized Role for Myosin Chaperones and Associated Proteins during Early Myofibrillogenesis

    PubMed Central

    Myhre, J. Layne; Pilgrim, David B.

    2012-01-01

    The development of striated muscle in vertebrates requires the assembly of contractile myofibrils, consisting of highly ordered bundles of protein filaments. Myofibril formation occurs by the stepwise addition of complex proteins, a process that is mediated by a variety of molecular chaperones and quality control factors. Most notably, myosin of the thick filament requires specialized chaperone activity during late myofibrillogenesis, including that of Hsp90 and its cofactor, Unc45b. Unc45b has been proposed to act exclusively as an adaptor molecule, stabilizing interactions between Hsp90 and myosin; however, recent discoveries in zebrafish and C. elegans suggest the possibility of an earlier role for Unc45b during myofibrillogenesis. This role may involve functional control of nonmuscle myosins during the earliest stages of myogenesis, when premyofibril scaffolds are first formed from dynamic cytoskeletal actin. This paper will outline several lines of evidence that converge to build a model for Unc45b activity during early myofibrillogenesis. PMID:22400118

  7. Bioengineered human myobundles mimic clinical responses of skeletal muscle to drugs.

    PubMed

    Madden, Lauran; Juhas, Mark; Kraus, William E; Truskey, George A; Bursac, Nenad

    2015-01-01

    Existing in vitro models of human skeletal muscle cannot recapitulate the organization and function of native muscle, limiting their use in physiological and pharmacological studies. Here, we demonstrate engineering of electrically and chemically responsive, contractile human muscle tissues ('myobundles') using primary myogenic cells. These biomimetic constructs exhibit aligned architecture, multinucleated and striated myofibers, and a Pax7(+) cell pool. They contract spontaneously and respond to electrical stimuli with twitch and tetanic contractions. Positive correlation between contractile force and GCaMP6-reported calcium responses enables non-invasive tracking of myobundle function and drug response. During culture, myobundles maintain functional acetylcholine receptors and structurally and functionally mature, evidenced by increased myofiber diameter and improved calcium handling and contractile strength. In response to diversely acting drugs, myobundles undergo dose-dependent hypertrophy or toxic myopathy similar to clinical outcomes. Human myobundles provide an enabling platform for predictive drug and toxicology screening and development of novel therapeutics for muscle-related disorders. PMID:25575180

  8. YAP-Mediated Mechanotransduction in Skeletal Muscle

    PubMed Central

    Fischer, Martina; Rikeit, Paul; Knaus, Petra; Coirault, Catherine

    2016-01-01

    Skeletal muscle is not only translating chemical energy into mechanical work, it is also a highly adaptive and regenerative tissue whose architecture and functionality is determined by its mechanical and physical environment. Processing intra- and extracellular mechanical signaling cues contributes to the regulation of cell growth, survival, migration and differentiation. Yes-associated Protein (YAP), a transcriptional coactivator downstream of the Hippo pathway and its paralog, the transcriptional co-activator with PDZ-binding motif (TAZ), were recently found to play a key role in mechanotransduction in various tissues including skeletal muscle. Furthermore, YAP/TAZ modulate myogenesis and muscle regeneration and abnormal YAP activity has been reported in muscular dystrophy and rhabdomyosarcoma. Here, we summarize the current knowledge of mechanosensing and -signaling in striated muscle. We highlight the role of YAP signaling and discuss the different routes and hypotheses of its regulation in the context of mechanotransduction. PMID:26909043

  9. Biology of MET: a double life between normal tissue repair and tumor progression

    PubMed Central

    2015-01-01

    MNNG HOS transforming gene (MET) is a class IV receptor tyrosine kinase, expressed on the surface of epithelial cells. The interaction with the hepatocyte grow factor (HGF) induces MET dimerization and the activation of multiple intracellular pathways leading to cell proliferation, anti-apoptosis, morphogenic differentiation, motility, invasion, and angiogenesis. Knock out mice have demonstrated that MET is necessary for normal embryogenesis including the formation of striate muscles, liver and trophoblastic structures. The overexpression of MET and HGF are common in solid tumors and contribute to determine their growth. Indeed, MET has been cloned as a transforming gene from a chemically induced human osteosarcoma cell line and therefore is considered a proto-oncogene. Germline MET mutations are characteristic of hereditary papillary kidney cancers and MET amplification is observed in tumors including lung and gastric adenocarcinomas. The inhibition of MET signaling is the target for specific drugs that are raising exciting expectation for medical treatment of cancer. PMID:25992381

  10. An easy and noninvasive technique for harvesting split thickness skin grafts in rats.

    PubMed

    Ersoy, Burak; Sahin Ersoy, Gulcin

    2016-06-01

    Skin graft studies in rats constitute a valuable adjunct to scientific human experimentations, however the harvesting of split thickness skin graft poses a challenge to the researcher due to the presence of panniculus carnosus tissue in rat skin. This striated muscle tissue renders significant laxity and mobility to the skin layer, greatly interfering with the process of skin graft harvest. In order to fixate the rat skin and limit its flexibility various techniques and modifications have been described, which mostly rely on the use of subdermal implanted templates. These methods are therefore time consuming, with an additional exposure to surgical stress and wounds. A new and simple technique is presented which offers a rapid and reliable alternative to the existing methods of split thickness skin graft harvesting without any additional invasive procedure or extra instruments other than the researchers hands and a dermatome. PMID:26899599

  11. Contribution to the knowledge of the oribatid mite genus Aeroppia (Acari, Oribatida, Oppiidae).

    PubMed

    Ermilov, Sergey G

    2016-01-01

    Two new species of the genus Aeroppia (Oribatida, Oppiidae) are described from upper soil and leaf litter in the primary evergreen lowland rainforest in Peru. Aeroppia friedrichi sp. nov. differs from A. nasalis Mahunka, 1984 by the absence of striate ornamentation on the notogaster and notogastral setae h1, and the presence of setiform adanal setae ad1. Aeroppia longisensilla sp. nov. differs from A. adjacens Mahunka, 1985 by the smaller body size and long bothridial setae. The supplementary descriptions of Aeroppia consimilis (Banks, 1910) and A. magnipilosa (Ewing, 1909) are presented, based on material from U.S.A. A new generic diagnosis for Aeroppia is given. The taxonomic status of the subgenus Aeroppia (Paraeroppia) Sanyal, 2009 is discussed, resulting in the following taxonomic proposal: Aeroppia Hammer, 1961 (=Aeroppia (Paraeroppia) Sanyal, 2009 syn. nov.). PMID:27470768

  12. Geometrical Origins of Contractility in Disordered Actomyosin Networks

    NASA Astrophysics Data System (ADS)

    Lenz, Martin

    2014-10-01

    Movement within eukaryotic cells largely originates from localized forces exerted by myosin motors on scaffolds of actin filaments. Although individual motors locally exert both contractile and extensile forces, large actomyosin structures at the cellular scale are overwhelmingly contractile, suggesting that the scaffold serves to favor contraction over extension. While this mechanism is well understood in highly organized striated muscle, its origin in disordered networks such as the cell cortex is unknown. Here, we develop a mathematical model of the actin scaffold's local two- or three-dimensional mechanics and identify four competing contraction mechanisms. We predict that one mechanism dominates, whereby local deformations of the actin break the balance between contraction and extension. In this mechanism, contractile forces result mostly from motors plucking the filaments transversely rather than buckling them longitudinally. These findings shed light on recent in vitro experiments and provide a new geometrical understanding of contractility in the myriad of disordered actomyosin systems found in vivo.

  13. Morphometric analysis of rat muscle fibers following space flight and hypogravity

    NASA Technical Reports Server (NTRS)

    Chui, L. A.; Castleman, K. R.

    1982-01-01

    The effect of hypogravity on striate muscles, containing both fast twitch glycolytic and slow twitch oxidative fibers, was studied in rats aboard two Cosmos biosatellites. Results of a computer-assisted image analysis of extensor digitorum muscles from five rats, exposed to 18.5 days of hypogravity and processed for the alkaline ATPase reaction, showed a reduction of the mean fiber diameter (41.32 + or - 0.55 microns), compared to synchronous (46.32 + or - 0.55 microns) and vivarium (49 + or - 0.5 microns) controls. A further experiment studied the ratio of fast to slow twitch fibers in 25 rats exposed to 18.5 days of hypogravity and analyzed at four different periods of recovery following the space flight. Using the previous techniques, the gastrocnemius muscle showed a reduction of the total muscle fiber area in square microns and a reduction in the percentage of slow fibers of flight animals compared to the control animals.

  14. Titin, a Central Mediator for Hypertrophic Signaling, Exercise-Induced Mechanosignaling and Skeletal Muscle Remodeling.

    PubMed

    Krüger, Martina; Kötter, Sebastian

    2016-01-01

    Titin is a giant scaffold protein with multiple functions in striated muscle physiology. Due to the elastic I-band domains and the filament-like integration in the half-sarcomere titin is an important factor for sarcomere assembly and serves as an adaptable molecular spring that determines myofilament distensibility. Protein-interactions e.g., with muscle ankyrin repeat proteins or muscle LIM-protein link titin to hypertrophic signaling and via p62 and Muscle Ring Finger proteins to mechanisms that control protein quality control. This review summarizes our current knowledge on titin as a central node for exercise-induced mechanosignaling and remodeling and further highlights the pathophysiological implications. PMID:26973541

  15. Early recurrent feedback facilitates visual object recognition under challenging conditions

    PubMed Central

    Wyatte, Dean; Jilk, David J.; O'Reilly, Randall C.

    2014-01-01

    Standard models of the visual object recognition pathway hold that a largely feedforward process from the retina through inferotemporal cortex leads to object identification. A subsequent feedback process originating in frontoparietal areas through reciprocal connections to striate cortex provides attentional support to salient or behaviorally-relevant features. Here, we review mounting evidence that feedback signals also originate within extrastriate regions and begin during the initial feedforward process. This feedback process is temporally dissociable from attention and provides important functions such as grouping, associational reinforcement, and filling-in of features. Local feedback signals operating concurrently with feedforward processing are important for object identification in noisy real-world situations, particularly when objects are partially occluded, unclear, or otherwise ambiguous. Altogether, the dissociation of early and late feedback processes presented here expands on current models of object identification, and suggests a dual role for descending feedback projections. PMID:25071647

  16. The solution of the Elrod algorithm for a dynamically loaded journal bearing using multigrid techniques

    NASA Technical Reports Server (NTRS)

    Woods, C. M.; Brewe, D. E.

    1989-01-01

    A numerical solution to a theoretical model of vapor cavitation in a dynamically loaded journal bearing is developed utilizing a multigrid iteration technique. The method is compared with a noniterative approach in terms of computational time and accuracy. The computational model is based on the Elrod algorithm, a control volume approach to the Reynolds equation which mimics the Jakobsson-Floberg and Olsson cavitation theory. Besides accounting for a moving cavitation boundary and conservation of mass at the boundary, it also conserves mass within the cavitated region via a smeared mass or striated flow extending to both surfaces in the film gap. The mixed nature of the equations (parabolic in the full film zone and hyperbolic in the cavitated zone) coupled with the dynamic aspects of the problem create interesting difficulties for the present solution approach. Emphasis is placed on the methods found to eliminate solution instabilities. Excellent results are obtained for both accuracy and reduction of computational time.

  17. Order-Disorder Transitions in the Cardiac Troponin Complex.

    PubMed

    Metskas, Lauren Ann; Rhoades, Elizabeth

    2016-07-31

    The troponin complex is a molecular switch that ties shifting intracellular calcium concentration to association and dissociation of actin and myosin, effectively allowing excitation-contraction coupling in striated muscle. Although there is a long history of muscle biophysics and structural biology, many of the mechanistic details that enable troponin's function remain incompletely understood. This review summarizes the current structural understanding of the troponin complex on the muscle thin filament, focusing on conformational changes in flexible regions of the troponin I subunit. In particular, we focus on order-disorder transitions in the C-terminal domain of troponin I, which have important implications in cardiac disease and could also have potential as a model system for the study of coupled binding and folding. PMID:27395017

  18. Alterations in Skeletal Muscle Microcirculation of Head-Down Tilted Rats

    NASA Technical Reports Server (NTRS)

    Musacchia, X. J.; Stepke, Bernhard; Fleming, John T.; Joshua, Irving G.

    1992-01-01

    In this study we assessed the function of microscopic blood vessels in skeletal muscle (cremaster muscle) for alterations which may contribute to the observed elevation of blood pressure associated with head-down tilted whole body suspension (HDT/WBS), a model of weightlessness. Arteriolar baseline diameters, vasoconstrictor responses to norepinephrine (NE) and vasodilation to nitroprusside (NP) were assessed in control rats, rats suspended for 7 or 14 day HDT/WBS rats, and rats allowed to recover for 1 day after 7 days HDT/WBS. Neither baseline diameters nor ability to dilate were influenced by HDT/WBS. Maximum vasoconstriction to norepinephrine was significantly greater in arterioles of hypertensive 14 day HDT/WBS rats. This first study of the intact microvasculature in skeletal muscle indicates that an elevated contractility of arterioles to norepinephrine in suspended rats, and suggests an elevated peripheral resistance in striated muscle may contribute to the increase in blood pressures among animals subjected to HDT/WBS.

  19. A new Lower Triassic ichthyopterygian assemblage from Fossil Hill, Nevada.

    PubMed

    Kelley, Neil P; Motani, Ryosuke; Embree, Patrick; Orchard, Michael J

    2016-01-01

    We report a new ichthyopterygian assemblage from Lower Triassic horizons of the Prida Formation at Fossil Hill in central Nevada. Although fragmentary, the specimens collected so far document a diverse fauna. One partial jaw exhibits isodont dentition with blunt tipped, mesiodistally compressed crowns and striated enamel. These features are shared with the Early Triassic genus Utatsusaurus known from coeval deposits in Japan and British Columbia. An additional specimen exhibits a different dentition characterized by relatively small, rounded posterior teeth resembling other Early Triassic ichthyopterygians, particularly Grippia. This Nevada assemblage marks a southward latitudinal extension for Early Triassic ichthyopterygians along the eastern margin of Panthalassa and indicates repeated trans-hemispheric dispersal events in Early Triassic ichthyopterygians. PMID:26855868

  20. Myasthenia Gravis—Current Concepts

    PubMed Central

    Herrmann, Christian; Lindstrom, Jon M.; Keesey, John C.; Mulder, Donald G.

    1985-01-01

    An edited summary of an Interdepartmental Conference arranged by the Department of Medicine of the UCLA School of Medicine, Los Angeles. The Director of Conferences is William M. Pardridge, MD, Associate Professor of Medicine. Current findings indicate that autoimmune myasthenia gravis is an acquired immune complex disorder of neuromuscular transmission in voluntary striated muscle. There is a break in immunologic tolerance leading to blocking and degradation of acetylcholine receptors, together with widening of the synaptic cleft associated with partial destruction, simplification and shortening of the postjunctional membrane. Thymic hyperplasia and thymoma may be present. A decremental response to nerve-muscle stimulation, blocking and jitter on single-fiber electromyography and circulating antibodies to acetylcholine receptor are detectable in most patients with generalized weakness. Although the cause of this abnormal immunologic mechanism remains to be discovered, anticholinesterases, corticosteroids, immunosuppressants, plasmapheresis or thymectomy (individually or in combination) provide control and better prognosis in most patients. ImagesFigure 1. PMID:3895751

  1. Laser and chemical surface modifications of titanium grade 2 for medical application

    NASA Astrophysics Data System (ADS)

    Kwaśniak, P.; Pura, J.; Zwolińska, M.; Wieciński, P.; Skarżyński, H.; Olszewski, L.; Marczak, J.; Garbacz, H.; Kurzydłowski, K. J.

    2015-05-01

    The article presents combined, chemical and physical approach to titanium surface functionalization designed for biomedical applications. The topography modification has been obtained by employing the double laser beam interference technique and chemical etching. In the outcome, clean and smooth Ti surface as well as periodic striated topography with the roughness range from nano- to micrometers were created. The obtained structures were characterized in terms of shape, roughness, chemical composition, mechanical properties and microstructures. In order to achieve all information, numerous of research methods have been used: scanning electron microscopy, atomic force microscopy, optical profilometry and microhardness measurements. Demonstrated methodology can be used as an effective tool for manufacturing controlled surface structures improving the bone-implants interactions.

  2. Molecular structure and pathophysiological roles of the Mitochondrial Calcium Uniporter.

    PubMed

    Mammucari, Cristina; Raffaello, Anna; Vecellio Reane, Denis; Rizzuto, Rosario

    2016-10-01

    Mitochondrial Ca(2+) uptake regulates a wide array of cell functions, from stimulation of aerobic metabolism and ATP production in physiological settings, to induction of cell death in pathological conditions. The molecular identity of the Mitochondrial Calcium Uniporter (MCU), the highly selective channel responsible for Ca(2+) entry through the IMM, has been described less than five years ago. Since then, research has been conducted to clarify the modulation of its activity, which relies on the dynamic interaction with regulatory proteins, and its contribution to the pathophysiology of organs and tissues. Particular attention has been placed on characterizing the role of MCU in cardiac and skeletal muscles. In this review we summarize the molecular structure and regulation of the MCU complex in addition to its pathophysiological role, with particular attention to striated muscle tissues. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou. PMID:26968367

  3. Snake velvet black: Hierarchical micro- and nanostructure enhances dark colouration in Bitis rhinoceros

    NASA Astrophysics Data System (ADS)

    Spinner, Marlene; Kovalev, Alexander; Gorb, Stanislav N.; Westhoff, Guido

    2013-05-01

    The West African Gaboon viper (Bitis rhinoceros) is a master of camouflage due to its colouration pattern. Its skin is geometrically patterned and features black spots that purport an exceptional spatial depth due to their velvety surface texture. Our study shades light on micromorphology, optical characteristics and principles behind such a velvet black appearance. We revealed a unique hierarchical pattern of leaf-like microstructures striated with nanoridges on the snake scales that coincides with the distribution of black colouration. Velvet black sites demonstrate four times lower reflectance and higher absorbance than other scales in the UV - near IR spectral range. The combination of surface structures impeding reflectance and absorbing dark pigments, deposited in the skin material, provides reflecting less than 11% of the light reflected by a polytetrafluoroethylene diffuse reflectance standard in any direction. A view-angle independent black structural colour in snakes is reported here for the first time.

  4. Pyomyositis in a 5-year-old child.

    PubMed

    Romeo, S; Sunshine, S

    2000-07-01

    We present a case of pyomyositis in an otherwise healthy 5-year-old child that underscores the potential for serious, life-threatening complications. Pyomyositis of the gluteal, psoas, and iliacus muscles was associated with osteomyelitis, septic arthritis, a large inferior vena cava thrombus, septic pulmonary emboli, and eventual pneumonia. Primary pyomyositis is a purulent infection of striated muscle thought to be caused by seeding from a transient bacteremia. The focal infection typically forms an abscess that generally responds to intravenous antibiotics and occasionally requires adjunctive computed tomography-guided aspiration and drainage. This localized infectious process rarely produces further sequelae unless treatment is delayed. Pyomyositis is rare in healthy individuals and requires a high clinical suspicion in patients who present with fever, leukocytosis, and localized pain. PMID:10910315

  5. Loss of desmoglein 1 associated with palmoplantar keratoderma, dermatitis and multiple allergies.

    PubMed

    Has, C; Jakob, T; He, Y; Kiritsi, D; Hausser, I; Bruckner-Tuderman, L

    2015-01-01

    Monoallelic desmoglein 1 mutations have been known for many years to cause striate palmoplantar keratoderma, but only recently, biallelic loss-of-function mutations were associated with a new disorder, designated as SAM syndrome (comprising severe dermatitis, multiple allergies and metabolic wasting) in two consanguineous families. We report on a new case from a third independent family with the homozygous nonsense mutation, c.2659C>T, p.R887* in exon 15 of DSG1 (desmoglein 1 gene). This mutation led to mRNA decay and loss of expression of desmoglein 1. The clinical phenotype consisted of severe palmoplantar keratoderma, dermatitis and multiple allergies. In contrast to the previous cases, malabsorption, hypoalbuminaemia, developmental delay, hypotrichosis or severe recurrent infections were not observed. PMID:25041099

  6. Snake velvet black: Hierarchical micro- and nanostructure enhances dark colouration in Bitis rhinoceros

    PubMed Central

    Spinner, Marlene; Kovalev, Alexander; Gorb, Stanislav N.; Westhoff, Guido

    2013-01-01

    The West African Gaboon viper (Bitis rhinoceros) is a master of camouflage due to its colouration pattern. Its skin is geometrically patterned and features black spots that purport an exceptional spatial depth due to their velvety surface texture. Our study shades light on micromorphology, optical characteristics and principles behind such a velvet black appearance. We revealed a unique hierarchical pattern of leaf-like microstructures striated with nanoridges on the snake scales that coincides with the distribution of black colouration. Velvet black sites demonstrate four times lower reflectance and higher absorbance than other scales in the UV – near IR spectral range. The combination of surface structures impeding reflectance and absorbing dark pigments, deposited in the skin material, provides reflecting less than 11% of the light reflected by a polytetrafluoroethylene diffuse reflectance standard in any direction. A view-angle independent black structural colour in snakes is reported here for the first time. PMID:23677278

  7. A muscle stem cell for every muscle: variability of satellite cell biology among different muscle groups

    PubMed Central

    Randolph, Matthew E.; Pavlath, Grace K.

    2015-01-01

    The human body contains approximately 640 individual skeletal muscles. Despite the fact that all of these muscles are composed of striated muscle tissue, the biology of these muscles and their associated muscle stem cell populations are quite diverse. Skeletal muscles are affected differentially by various muscular dystrophies (MDs), such that certain genetic mutations specifically alter muscle function in only a subset of muscles. Additionally, defective muscle stem cells have been implicated in the pathology of some MDs. The biology of muscle stem cells varies depending on the muscles with which they are associated. Here we review the biology of skeletal muscle stem cell populations of eight different muscle groups. Understanding the biological variation of skeletal muscles and their resident stem cells could provide valuable insight into mechanisms underlying the susceptibility of certain muscles to myopathic disease. PMID:26500547

  8. Hydride vapor phase epitaxy of high quality {101¯3¯} semipolar GaN on m-plane sapphire coated with self-assembled SiO2 nanospheres

    NASA Astrophysics Data System (ADS)

    Yang, Jiankun; Wei, Tongbo; Huo, Ziqiang; Hu, Qiang; Zhang, Yonghui; Duan, Ruifei; Wang, Junxi

    2014-02-01

    Semipolar {101¯3¯} GaN layers were grown on self-assembled SiO2 nanospheres sapphire (SSNS) by hydride vapor phase epitaxy. The RMS roughness was 1.1 nm for the scan of 20×20 µm2 and the striated surface morphology almost disappeared. The full widths at half maximum of on-axis X-ray rocking curves were 324 arcsec rocking toward the [303¯2¯] direction and 413 arcsec rocking toward the [12¯10] direction, respectively. Compared to the GaN layer grown on the planar sapphire, the reduction of the defect density of semi-GaN grown on SSNS, such as basal stacking faults, partial dislocations and perfect dislocations, was demonstrated by both X-ray rocking curves and low-temperature photoluminescence. In addition, the Raman analyses also showed the partial relaxation of the stress using SSNS.

  9. Laser injury to multiple retinal foci

    SciTech Connect

    Kearney, J.J.; Cohen, H.B.; Stuck, B.E.; Rudd, G.P.; Beresky, D.E.; Wertz, F.D.

    1987-01-01

    A 21-year-old man received an accidental laser injury to three separate foci of the retina of his right eye from a Q-switched Nd:YAG laser target designator emitting at 1064 nm, operating at 10 Hz, with a pulse duration of 20 ns. The nominal output of this device was 50 mJ, and the diameter of the output beam was approximately 4 cm. The extent of injury consisted of retinal necrosis, subretinal hemorrhage, vitreous hemorrhage, and striate retinopathy. The initial visual acuity was 20/400, but quickly recovered to 20/30. One year following injury the visual acuity was 20/40. Mature chorioretinal scars were apparent. A preretinal membrane was evident with marked wrinkling effect on the macular area of the retina.

  10. Chorea associated with anti-phospholipid antibodies: case report.

    PubMed

    Demonty, J; Gonce, M; Ribai, P; Verellen-Dumoulin, C; Hustinx, R

    2010-01-01

    A seventeen year-old boy developed left sided chorea in a few days, subsequently involving the four limbs. Although he presented a marfanoid phenotype, genetic analysis of the Fibrillin 1 was normal. The genes for familial chorea and Huntington's disease were also negative. Biological tests showed normal serum homocystein, but revealed very high levels of anti-beta2-GP1 IgG, anticardiolipin and lupus anticoagulant, which remained at similar values for a period of over three months. Electroencephalogram and cerebral magnetic resonance imaging (MRI) showed no abnormalities. Brain PET-scan disclosed bilateral striatal hypermetabolism. The patient was treated with methylprednisolone and low dose of acetylsalicylic acid. He improved markedly after six weeks of treatment, and choreic movements disappeared completely after two months. A control PET-scan performed at this time showed reversion of striated hypermetabolism to a normal pattern. The pathogenic aspects of this relatively rare case of chorea are discussed. PMID:21128564

  11. Mid-Pleistocene cosmogenic minimum-age limits for pre-Wisconsinan glacial surfaces in southwestern Minnesota and southern Baffin Island: A multiple nuclide approach

    USGS Publications Warehouse

    Bierman, P.R.; Marsella, K.A.; Patterson, Chris; Davis, P.T.; Caffee, M.

    1999-01-01

    Paired 10Be and 26Al analyses (n = 14) indicate that pre-Wisconsinan, glaciated bedrock surfaces near the northern (Baffin Island) and southern (Minnesota) paleo-margins of the Laurentide Ice Sheet have long and complex histories of cosmic-ray exposure, including significant periods of partial or complete shielding from cosmic rays. Using the ratio, 26Al/10Be, we calculate that striated outcrops of Sioux Quartzite in southwestern Minnesota (southern margin) were last overrun by ice at least 500,000 years ago. Weathered bedrock tors on the once-glaciated uplands of Baffin Island (northern margin) are eroding no faster than 1.1 m Myr-1, the equivalent of at least 450,000 years of surface and near-surface exposure. Our data demonstrate that exposure ages and erosion rates calculated from single nuclides can underestimate surface stability dramatically because any intermittent burial, and the resultant lowering of nuclide production rates and nuclide abundances, will remain undetected.

  12. Therapeutic gymnastics in comprehensive treatment of patients with generalized myasthenia

    NASA Technical Reports Server (NTRS)

    Kapelovich, R. L.

    1980-01-01

    The technique of therapeutic gymnastics was used for patients with mayasthenia gravis to control the consequences of hypodynamia induced by the myasthenic process. It is concluded that during myasthenia, the severity of the disease is due to the affection of the cross striated musculature. The most life threatening are the disorders in respiration and swallowing, that can be intensified by forced stay in bed and immobility. It is also concluded that the use of therapeutic gymnastics in patients which myasthenia promotes efficient presurgical preparation, and in the post surgical period; prevention of pulmonary complications and normalization of respiration. Therapeutic gymnastics with regard to the severity and localization of the myasthenic disorders must be a component part of the presurgical preparation and postsurgical management of patients with generalized myasthenia.

  13. Selecting Valid Correlation Areas for Automated Bullet Identification System Based on Striation Detection

    PubMed Central

    Chu, Wei; Song, John; Vorburger, Theodore V.; Thompson, Robert; Silver, Richard

    2011-01-01

    Some automated bullet identification systems calculate a correlation score between two land impressions to measure their similarity. When extracting a compressed profile from the land impression of a fired bullet, inclusion of areas that do not contain valid individual striation information may lead to sub-optimal extraction and therefore may deteriorate the correlation result. In this paper, an edge detection algorithm and selection process are used together to locate the edge points of all tool-mark features and filter out those not corresponding to striation marks. Edge points of the resulting striation marks are reserved and expanded to generate a mask image. By imposing the mask image on the topography image, the weakly striated area(s) are removed from the expressed profile extraction. Using this method, 48 bullets fired from 12 gun barrels of six manufacturers resulted in a higher matching rate than previous studies. PMID:26989589

  14. TNNT1, TNNT2, and TNNT3: Isoform genes, regulation, and structure-function relationships.

    PubMed

    Wei, Bin; Jin, J-P

    2016-05-10

    Troponin T (TnT) is a central player in the calcium regulation of actin thin filament function and is essential for the contraction of striated muscles. Three homologous genes have evolved in vertebrates to encode three muscle type-specific TnT isoforms: TNNT1 for slow skeletal muscle TnT, TNNT2 for cardiac muscle TnT, and TNNT3 for fast skeletal muscle TnT. Alternative splicing and posttranslational modifications confer additional structural and functional variations of TnT during development and muscle adaptation to various physiological and pathological conditions. This review focuses on the TnT isoform genes and their molecular evolution, alternative splicing, developmental regulation, structure-function relationships of TnT proteins, posttranslational modifications, and myopathic mutations and abnormal splicing. The goal is to provide a concise summary of the current knowledge and some perspectives for future research and translational applications. PMID:26774798

  15. Cloning and sequencing of a cDNA for Akazara scallop troponin T.

    PubMed

    Inoue, A; Ojima, T; Nishita, K

    1996-10-01

    A cDNA clone encoding troponin T of Akazara scallop (Chlamys nipponensis akazara) striated adductor muscle has been isolated and sequenced. The complete sequence deduced consists of 314 amino acid residues with a molecular weight of 37,206. Akazara scallop troponin T contains 55 amino acid residues more and 82 residues fewer than rabbit skeletal muscle troponin T and Drosophila melanogaster troponin T, respectively, showing almost the lowest sequence homology with rabbit troponin T (26%) but the highest homology with Drosophila troponin T (33%). Further, high sequence homology was seen in the functional regions: residues 33-120 and 174-227, corresponding respectively to residues 71-158 and 197-250 of rabbit troponin T (tropomyosin-binding regions); and residues 200-204, corresponding to 223 227 of rabbit troponin T (troponin I-binding region). In residues 1-70 (tropomyosin-binding region), however, only six residues are identical with rabbit troponin T. PMID:8947849

  16. Developmental and hormonal regulation of protein H1 degrees in rodents.

    PubMed Central

    Gjerset, R; Gorka, C; Hasthorpe, S; Lawrence, J J; Eisen, H

    1982-01-01

    The tissue and cellular distribution and regulation of the chromatin protein H1 degrees has been examined in developing and adult mouse and in rat. The protein appears in specific cell types of solid tissues only when the cells have terminated their maturation. This was found for brain, retina, striated and cardiac muscle, and liver. In tissues that depend on hormones for their function and maintenance, the expression of H1 degrees is dependent on the continued presence of the specific maintenance hormone. In regenerating rat liver the amount of H1 degrees decreases to one-third after the onset of DNA synthesis. The possible role of H1 degrees is discussed in light of these results. Images PMID:6954544

  17. Flaw growth of 7075, 7475, 7050 and 7049 aluminum alloy plate in stress corrosion environments: 4-year marine atmosphere results

    NASA Technical Reports Server (NTRS)

    Hasse, K. R.; Dorward, R. C.

    1981-01-01

    After nearly 53 months of exposure to marine atmosphere, crack growth in SL DCB specimens from 7075, 7475, 7050, and 7049-T7X plate has slowed to the arbitrary 10 to the -10 power m/sec used to define threshold stress intensity. Because some specimens appear to be approaching crack arrest, the importance of self-loading from corrosion product wedging as a significant driving force for crack propagation in overaged materials is questioned. Crack length-time data were analyzed using a computer curve fitting program which minimized the effects of normal data scatter, and provided a clearer picture of material performance. Precracked specimen data are supported by the results of smooth specimen tests. Transgranular stress corrosion cracking was observed in TL DCB specimens from all four alloys. This process is extremely slow and is characterized by a striated surface morphology.

  18. Application of electrical stimulation for functional tissue engineering in vitro and in vivo

    NASA Technical Reports Server (NTRS)

    Radisic, Milica (Inventor); Park, Hyoungshin (Inventor); Langer, Robert (Inventor); Freed, Lisa (Inventor); Vunjak-Novakovic, Gordana (Inventor)

    2013-01-01

    The present invention provides new methods for the in vitro preparation of bioartificial tissue equivalents and their enhanced integration after implantation in vivo. These methods include submitting a tissue construct to a biomimetic electrical stimulation during cultivation in vitro to improve its structural and functional properties, and/or in vivo, after implantation of the construct, to enhance its integration with host tissue and increase cell survival and functionality. The inventive methods are particularly useful for the production of bioartificial equivalents and/or the repair and replacement of native tissues that contain electrically excitable cells and are subject to electrical stimulation in vivo, such as, for example, cardiac muscle tissue, striated skeletal muscle tissue, smooth muscle tissue, bone, vasculature, and nerve tissue.

  19. Loss of Sarcomere-associated Formins Disrupts Z-line Organization, but does not Prevent Thin Filament Assembly in Caenorhabditis elegans Muscle

    PubMed Central

    Mi-Mi, Lei; Pruyne, David

    2015-01-01

    Members of the formin family of actin filament nucleation factors have been implicated in sarcomere formation, but precisely how these proteins affect sarcomere structure remains poorly understood. Of six formins in the simple nematode Caenorhabditis elegans, only FHOD-1 and CYK-1 contribute to sarcomere assembly in the worm's obliquely striated body-wall muscles. We analyze here the ultrastructure of body-wall muscle sarcomeres in worms with putative null fhod-1 and cyk-1 gene mutations. Contrary to a simple model that formins nucleate actin for thin filament assembly, formin mutant sarcomeres contain thin filaments. Rather, formin mutant sarcomeres are narrower and have deformed thin filament-anchoring Z-line structures. Thus, formins affect multiple aspects of sarcomere structure. PMID:26161293

  20. Polymyositis and dermatomyositis as a risk of developing cancer

    PubMed Central

    Kwiatkowska, Brygida; Maślińska, Maria

    2015-01-01

    Polymyositis (PM) is an idiopathic inflammatory myopathy that affects striated muscles. Dermatomyositis (DM) is an idiopathic inflammatory myopathy with presence of skin symptoms. Both are characterized by acute or subacute onset, symmetrical proximal muscle weakness, the presence of mononuclear cell infiltrates of the muscles and increased activity of muscle enzymes. The treatment still remains glucocorticoids and disease-modifying drugs. Symptoms of PM/DM can be a signal of developing cancer. Known risk factors for cancer in patients with PM/DM are older age, male gender, dysphagia, skin necrosis, cutaneous vasculitis, rapid onset of the disease, elevated creatinine kinase (CK) and C reactive protein (CRP), and an increase in the erythrocyte sedimentation rate (ESR). Recently three new myositis-specific autoantibodies (MSA) predicting the risk of cancer have been discovered: melanoma differentiation-associated protein 5 (anti-MDA-5), transcription intermediary factor 1γ (TIF-1γ), and nuclear matrix protein NXP-2.

  1. Gastric emptying, small intestinal transit and fecal output in dystrophic (mdx) mice.

    PubMed

    Mulè, Flavia; Amato, Antonella; Serio, Rosa

    2010-01-01

    Duchenne muscular dystrophy (DMD), which results from deficiency in dystrophin, a sarcolemma protein of skeletal, cardiac and smooth muscle, is characterized by progressive striated muscle degeneration, but various gastrointestinal clinical manifestations have been observed. The aim was to evaluate the possible impact of the dystrophin loss on the gastrointestinal propulsion in mdx mice (animal model for DMD). The gastric emptying of a carboxymethyl cellulose/phenol red dye non-nutrient meal was not significantly different at 20 min from gavaging between wild-type and mdx mice. The intestinal transit and the fecal output were significantly decreased in mdx versus normal animals, although the length of the intestine was similar in both animals. The present results provide evidence for motor intestinal alterations in mdx mice in in vivo conditions. PMID:19784719

  2. Atrophy of submandibular gland by the duct ligation and a blockade of SP receptor in rats

    PubMed Central

    Hishida, Sumiyo; Ozaki, Noriyuki; Honda, Takashi; Shigetomi, Toshio; Ueda, Minoru; Hibi, Hideharu; Sugiura, Yasuo

    2016-01-01

    ABSTRACT To clarify the mechanisms underlying the submandibular gland atrophies associated with ptyalolithiasis, morphological changes were examined in the rat submandibular gland following either surgical intervention of the duct or functional blockade at substance P receptors (SPRs). Progressive acinar atrophy was observed after duct ligation or avulsion of periductal tissues. This suggested that damage to periductal tissue involving nerve fibers might contribute to ligation-associated acinar atrophy. Immunohistochemically labeled-substance P positive nerve fibers (SPFs) coursed in parallel with the main duct and were distributed around the interlobular, striated, granular and intercalated duct, and glandular acini. Strong SPR immunoreactivity was observed in the duct. Injection into the submandibular gland of a SPR antagonist induced marked acinar atrophy. The results revealed that disturbance of SPFs and SPRs might be involved in the atrophy of the submandibular gland associated with ptyalolithiasis. PMID:27303108

  3. Immunohistochemical Properties of the Peripheral Neurons Projecting to the Pig Bulbospongiosus Muscle.

    PubMed

    Botti, Maddalena; Ragionieri, Luisa; Cacchioli, Antonio; Panu, Rino; Gazza, Ferdinando

    2016-09-01

    Retrograde neuronal tracing and single labelling immunofluorescence methods were used to define the neurochemical content of the peripheral autonomic and sensitive neurons projecting to the male pig striated bulbospongiosus muscle (BSM). The retrograde fluorescent neuronal tracer Fast Blue (FB) was injected into the left bulbospongiosus muscle of four intact impuberal pigs. After a 10-day survival time, the ipsilateral sacral sympathetic trunk ganglia (STGs), the caudal mesenteric ganglion (CMG), and the sacral spinal ganglia (SGs) were collected from each animal. In FB+ neurons of these ganglia, the presence of cathecolamine- (tyrosine hydroxylase-TH), acetylcholine- (vesicular acetylcholine transporter-VChAT), or nitric oxide-synthesizing (neuronal Nitric Oxide Synthase-nNOS) enzymes and of some biologically active peptides (calcitonine gene-related peptide-CGRP, Leu-Enkephaline-LENK, Neuropeptide Y-NPY, Substance P-SP and Vasoactive Intestinal Peptide-VIP) were studied. The ipsilateral STGs FB+ neurons showed immunoreactivity principally for TH and NPY and in decreasing order for VIP, VChAT, SP, CGRP, nNOS, and LENK. The left CMG FB+ neurons were immunoreactive to TH and NPY, and in smaller proportions for VIP, LENK, VChAT, CGRP, nNOS, and SP. The ipsilateral SGs FB+ neurons resulted immunoractive for CGRP, LENK, NPY, nNOS, SP, and VChAT. The heterogeneous neurochemical content of the peripheral neurons projecting to the pig BSM allows us to hypothesize the involvement of autonomic ganglia in the activity of both blood vessels and striated fibers of the muscle and the involvement of sensory ganglia in the afferent transmission from the muscle to spinal cord and in antidromic mechanisms that causes the relaxation of the BSM blood vessels. Anat Rec, 299:1192-1202, 2016. © 2016 Wiley Periodicals, Inc. PMID:27342415

  4. Anatomic and acoustic sexual dimorphism in the sound emission system of Phoenicoprocta capistrata (Lepidoptera: Arctiidae)

    NASA Astrophysics Data System (ADS)

    Rodríguez-Loeches, Laura; Barro, Alejandro; Pérez, Martha; Coro, Frank

    2009-04-01

    Both sexes of Phoenicoprocta capistrata have functional tymbals. The scanning electron microscopy revealed differences in the morphology of these organs in males and females. Male tymbals have a well-developed striated band, constituted by 21 ± 2 regularly arranged striae whereas female tymbals lack a striated band. This type of sexual dimorphism is rare in Arctiidae. The recording of the sound produced by moths held by the wings revealed that while males produced trains of pulses organized in modulation cycles, females produced clicks at low repetition rate following very irregular patterns. Statistically, there are differences between sexes in terms of the duration of pulses, which were 355 ± 24 μs in the case of males and 289 ± 29 μs for females. The spectral characteristics of the pulses also show sexual dimorphism. Male pulses are more tuned ( Q 10 = 5.2 ± 0.5) than female pulses ( Q 10 = 2.7 ± 0.5) and have a higher best frequency (42 ± 1 kHz vs. 29 ± 2 kHz). To our knowledge, this is the first report on an arctiid moth showing sexual dimorphism in tymbal’s anatomy that leads to a best frequency dimorphism. Males produce sound at mating attempts. The sounds recorded during mating are modulation cycles with the same spectral characteristics as those recorded when males are held by the wings. The morphological and acoustic features of female tymbals could indicate a process of degeneration and adaptation to conditions under which the emission of complex patterns is not necessary.

  5. Distribution of calcitonin gene-related peptide in vertebrate neuromuscular junctions: relationship to the acetylcholine receptor.

    PubMed

    Csillik, B; Tajti, L; Kovács, T; Kukla, E; Rakic, P; Knyihár-Csillik, E

    1993-10-01

    Calcitonin gene-related peptide (CGRP), regarded by several authors to be involved in maintenance of the acetylcholine receptor, is present in the motor axons of various striated rat muscles. It is present, however, only in motor endplates of several selected striated muscles, where it is located in presynaptic axon terminals of neuromuscular junctions. No immunoreactivity could be seen within synaptic vesicles themselves. In the non-human primate Macaca fasciculata, neuromuscular junctions, including those in the diaphragm, display an intense CGRP reaction. The structure of the simian motor endplates is more elaborate than that of the rat. Amphibian motor nerve endings, both in tetanic and tonic muscles, display CGRP immunoreactivity. In tetanic muscles the CGRP reaction outlines "terminaisons en placque" (true motor end plates) and weakly reacting "terminaisons en grappe" (grape-like endings) in tonic muscles. On supramaximal stimulation of the motor nerve, CGRP is depleted from the affected neuromuscular junctions. Wallerian degeneration of the motor axon results in complete disappearance of CGRP. In most rat muscles in which motor endplates do not normally exhibit CGRP immunoreactivity, e.g., the diaphragm and buccinator muscles, the pre-terminal motor axons are CGRP-positive. After immobilization of such muscles by local bupivacaine injection to rats under brief chloral hydrate anesthesia, CGRP immunoreactivity of the neuromuscular junctions can be elicited because blockade of neuromuscular transmission results in accumulation of CGRP in the endplates. Even more striking is the appearance of CGRP immunoreactivity in normally non-reactive motor endplates during axon regeneration after an experimentally induced Wallerian degeneration of the motor axons. We conclude that CGRP is a regular, genotypically determined component of neuromuscular junctions, present either in a manifest or in a latent form. The latter can be elicited by various experimental approaches

  6. Die Cnidogenese der Octocorallia (Anthozoa, Cnidaria): II. Reifung, Wanderung und Zerfall von Cnidoblast und Nesselkapsel

    NASA Astrophysics Data System (ADS)

    Schmidt, H.; Moraw, B.

    1982-03-01

    Migration of cnidoblasts has never been observed in Anthozoa. In contrast to hydrozoans, anthozoans are repeatedly reported to develop nematocysts locally without migration in the entoderm as well as in the ectoderm. The majority of the nematocysts studied in different Octocorallia species (Alcyonaria: Alcyonarium digitatum, Parerythropodium coralloides; Gorgonaria: Pseudopterogorgia aerosa; Pennatularia: Veretillum cynomorium) originate from the ectoderm of the scapus, where, however, no mature nematocysts occur. Cnidoblasts containing immature nematocysts accumulate in the distal scapus, from where they migrate singly like amoebae into the pinnulae of the tentacles. The nematocysts mature during migration, during which the capsular matrix becomes completely electron-translucent. Only in the oral disc, where few nematocysts occur, do they mature locally without migration. In the Octocorallia, nematocyst development and maturation takes places only in the ectoderm. Development of nematocysts has never been observed in the entoderm, nor in the pharynx; this demonstrates its entodermal origin. The entoderm contains only degenerated or phagocytized nematocysts. Contrary to hydrozoans, the mature anthozoan cnidocyte is rounded and has no processes to the mesogloea. Instead of a cnidocil it has a ciliary cone consisting of a normal flagellum, stereocilia and macrovilli. The cnidocyte is characterised by abundant electron-translucent cytoplasm and nematocyst-anchoring structures made up of cross-striated, collagen-like fibrillae and a fibrous basal ring. The position of the cross-striated fibrillae is distally similar to that of the supportive rods in hydrozoan cnidoblasts. The present study clearly demonstrates that structure and, possibly, function of an octocorallian cnidocyte is much simpler than that of a hydrozoan cnidocyte. On the other hand, cnidoblast migration, occurring in Hydrozoa as well in Octocorallia, turned out to be a much older phylogenetic character

  7. Loss of the Tectorial Membrane Protein CEACAM16 Enhances Spontaneous, Stimulus-Frequency, and Transiently Evoked Otoacoustic Emissions

    PubMed Central

    Goodyear, Richard J.; Homma, Kazuaki; Legan, P. Kevin; Korchagina, Julia; Naskar, Souvik; Siegel, Jonathan H.; Dallos, Peter; Zheng, Jing

    2014-01-01

    α-Tectorin (TECTA), β-tectorin (TECTB), and carcinoembryonic antigen-related cell adhesion molecule 16 (CEACAM) are secreted glycoproteins that are present in the tectorial membrane (TM), an extracellular structure overlying the hearing organ of the inner ear, the organ of Corti. Previous studies have shown that TECTA and TECTB are both required for formation of the striated-sheet matrix within which collagen fibrils of the TM are imbedded and that CEACAM16 interacts with TECTA. To learn more about the structural and functional significance of CEACAM16, we created a Ceacam16-null mutant mouse. In the absence of CEACAM16, TECTB levels are reduced, a clearly defined striated-sheet matrix does not develop, and Hensen's stripe, a prominent feature in the basal two-thirds of the TM in WT mice, is absent. CEACAM16 is also shown to interact with TECTB, indicating that it may stabilize interactions between TECTA and TECTB. Although brain-stem evoked responses and distortion product otoacoustic emissions are, for most frequencies, normal in young mice lacking CEACAM16, stimulus-frequency and transiently evoked emissions are larger. We also observed spontaneous otoacoustic emissions (SOAEs) in 70% of the homozygous mice. This incidence is remarkable considering that <3% of WT controls have SOAEs. The predominance of SOAEs >15 kHz correlates with the loss of Hensen's stripe. Results from mice lacking CEACAM16 are consistent with the idea that the organ of Corti evolved to maximize the gain of the cochlear amplifier while preventing large oscillations. Changes in TM structure appear to influence the balance between energy generation and dissipation such that the system becomes unstable. PMID:25080593

  8. Reproductive morphology of Brittanichthys axelrodi (Teleostei: Characidae), a miniature inseminating fish from South America.

    PubMed

    Javonillo, Robert; Burns, John R; Weitzman, Stanley H

    2007-01-01

    Light and electron microscopy were used to investigate the morphology of reproductive characters in a characid fish, Brittanichthys axelrodi. Spermatozoa were found in ovaries of females, thereby confirming insemination in this species. Bony hooks can be found on the fourth unbranched ray and branched rays 1-4 of the anal fin and the unique sigmoidally-curved ray of the caudal fin in mature males. Testes have three distinct regions: an anterior spermatogenic region, an aspermatogenic middle region lined with a simple squamous epithelium and used for storage of mature spermatozoa, and a posterior region of coiled chambers lined with a high simple cuboidal epithelium. The most posterior region appears to be instrumental in the formation and storage of spermatozeugmata, unencapsulated sperm packets. Thus far, this tripartite testis morphology is unique among characids. The mature spermatozoon has an elongate nucleus ( approximately 5 microm in length). A striated rootlet originates at the anterior end of the distal centriole and continues to the anterior tip of the cell. The striated rootlet wraps around the entire ventral area of the anterior part of the nucleus and appears to continue around the anterior tip of the nucleus and down the dorsal side as electron-dense material. Several large, spherical mitochondria ( approximately 0.6 microm in diameter) with lamellar cristae overlap the posterior end of the nucleus and continue beyond together with the cytoplasmic collar that contains the flagellum which lacks axonemal fins. Each spermatozeugma is lanceolate in shape when sectioned mid-sagitally, with the core staining positively for mucopolysaccharides. In both sexes, the gonopore opens posterior to the anus, with the urinary pore having a separate opening posterior to the gonopore. Bands of skeletal muscle were found in the area of the male gonopore. These morphological features are likely linked to the reproductive mode of insemination, a trait that is so far as

  9. Characterization of Esophageal Physiology Using Mechanical State Analysis

    PubMed Central

    Leibbrandt, Richard E.; Dinning, Phil G.; Costa, Marcello; Cock, Charles; Wiklendt, Lukasz; Wang, Guangsong; Tack, Jan; van Beckevoort, Dirk; Rommel, Nathalie; Omari, Taher I.

    2016-01-01

    The esophagus functions to transport swallowed fluids and food from the pharynx to the stomach. The esophageal muscles governing bolus transport comprise circular striated muscle of the proximal esophagus and circular smooth muscle of the distal esophagus. Longitudinal smooth muscle contraction provides a mechanical advantage to bolus transit during circular smooth muscle contraction. Esophageal striated muscle is directly controlled by neural circuits originating in the central nervous system, resulting in coordinated contractions. In contrast, the esophageal smooth muscle is controlled by enteric circuits modulated by extrinsic central neural connections resulting in neural relaxation and contraction. The esophageal muscles are modulated by sensory information arising from within the lumen. Contraction or relaxation, which changes the diameter of the lumen, alters the intraluminal pressure and ultimately inhibits or promotes flow of content. This relationship that exists between the changes in diameter and concurrent changes in intraluminal pressure has been used previously to identify the “mechanical states” of the circular muscle; that is when the muscles are passively or actively, relaxing or contracting. Detecting these changes in the mechanical state of the muscle has been difficult and as the current interpretation of esophageal motility is based largely upon pressure measurement (manometry), subtle changes in the muscle function during peristalsis can be missed. We hypothesized that quantification of mechanical states of the esophageal circular muscles and the pressure-diameter properties that define them, would allow objective characterization of the mechanisms that govern esophageal peristalsis. To achieve this we analyzed barium swallows captured by simultaneous videofluoroscopy and pressure with impedance recording. From these data we demonstrated that intraluminal impedance measurements could be used to determine changes in the internal diameter

  10. Structural characterization and regulatory element analysis of the heart isoform of cytochrome c oxidase VIa

    NASA Technical Reports Server (NTRS)

    Wan, B.; Moreadith, R. W.; Blomqvist, C. G. (Principal Investigator)

    1995-01-01

    In order to investigate the mechanism(s) governing the striated muscle-specific expression of cytochrome c oxidase VIaH we have characterized the murine gene and analyzed its transcriptional regulatory elements in skeletal myogenic cell lines. The gene is single copy, spans 689 base pairs (bp), and is comprised of three exons. The 5'-ends of transcripts from the gene are heterogeneous, but the most abundant transcript includes a 5'-untranslated region of 30 nucleotides. When fused to the luciferase reporter gene, the 3.5-kilobase 5'-flanking region of the gene directed the expression of the heterologous protein selectively in differentiated Sol8 cells and transgenic mice, recapitulating the pattern of expression of the endogenous gene. Deletion analysis identified a 300-bp fragment sufficient to direct the myotube-specific expression of luciferase in Sol8 cells. The region lacks an apparent TATA element, and sequence motifs predicted to bind NRF-1, NRF-2, ox-box, or PPAR factors known to regulate other nuclear genes encoding mitochondrial proteins are not evident. Mutational analysis, however, identified two cis-elements necessary for the high level expression of the reporter protein: a MEF2 consensus element at -90 to -81 bp and an E-box element at -147 to -142 bp. Additional E-box motifs at closely located positions were mutated without loss of transcriptional activity. The dependence of transcriptional activation of cytochrome c oxidase VIaH on cis-elements similar to those found in contractile protein genes suggests that the striated muscle-specific expression is coregulated by mechanisms that control the lineage-specific expression of several contractile and cytosolic proteins.

  11. Clinical significance of immunopathological findings in patients with post-pericardiotomy syndrome. I. Relevance of antibody pattern

    PubMed Central

    Maisch, B.; Berg, P. A.; Kochsiek, K.

    1979-01-01

    Sera from sixty-five patients were collected before and after cardiac surgery to determine striated muscle antibodies (anti-heart and anti-skeletal), non-organ-specific antibodies, immunoglobulin and complement levels. According to the clinical features of pericarditis, fever and leucocytosis, patients were divided into three groups: (1) complete post-pericardotomy syndrome (PPS) (n = 19) with all three symptoms; (2) incomplete PPS with two symptoms (n = 18); and (3) no PPS with one or no symtpoms (n = 28). Almost all the patients with complete PPS, two thirds of the patients with incomplete PPS and one third of the patients with no PPS showed striated muscle antibodies. Anti-sarcolemmal antibodies predominated. In patients with complete PPS, antibodies persisted beyond the fourth post-operative week and correlated well with symptoms. An even better correlation with the syndrome could be obtained by including the post-operative occurrence of anti-endothelial (AEA), smooth muscle (SMA), the pre- and post-operative frequency of antinuclear antibodies (ANA) and the increase in immunoglobulin concentrations after surgery in an immunological grading system. These criteria permitted a redistribution of the nineteen patients with an incomplete PPS: fourteen were immunologically positive for a PPS. Although autoantibodies are predominantly associated with PPS, their role in the pathogenesis of the syndrome is not clear. The complementary influence of surgical and non-surgical factors, such as the degree of myocardial damage, the time of ischemia during the operation and a possible viral infection by blood transfusion, is analysed. PMID:527258

  12. Spectrum of Infantile Esotropia in Primates: Behavior, Brains and Orbits

    PubMed Central

    Tychsen, Lawrence; Richards, Michael; Wong, Agnes; Foeller, Paul; Burhkalter, Andreas; Narasimhan, Anita; Demer, Joseph

    2009-01-01

    Introduction Recent studies of human infants have described a spectrum of early-onset esotropia, from small-variable-angle to large heterotropias.1 We report here a similar spectrum of early-onset esotropia in infant monkeys, with emphasis on the relationship between visuomotor deficits, central nervous system (CNS) circuitry and orbital anatomy. Methods Eye movements were recorded in macaque monkeys with natural, infantile-onset esotropia (n=7) and in control monkeys (n=2) to assess alignment, latent nystagmus, dissociated vertical deviation (DVD), and pursuit/optokinetic nystagmus (OKN) asymmetries. Acuity was measured by preferential-looking technique or spatial sweep VEP (SSVEP). Geniculo-striate pathways were then analyzed with neuroanatomic tracers and metabolic labels. Extraocular muscles were examined by high-resolution magnetic resonance imaging (MRI) and anatomic sectioning of whole orbits. Results Esotropia ranged from 4-13.5° (7-24 prism diopters [PD]) with fixation preference (if any) varying idiosyncratically (as in human). Severity of ocular motor dysfunction (i.e. nystagmus velocity, DVD amplitude, pursuit-OKN nasal bias index), increased as the magnitude of esotropia angle. Animals with greater ocular motor deficits tended to have greater visual area V1 (striate cortex) neuroanatomic deficits, evident as fewer binocular horizontal connections in V1. Orbital MRI/anatomic analysis showed no difference in horizontal rectus cross sectional areas, muscle paths, innervation densities or cytoarchitecture compared to normal animals. Conclusion The infantile esotropia spectrum in non-human primates is remarkably similar to that reported in human infants. Concomitant esotropia in these primates cannot be ascribed to abnormalities of the extraocular muscles or orbit. These findings, combined with epidemiologic studies of human, suggest that perturbations of CNS binocular pathways in early development are the primary cause of the infantile esotropia syndrome

  13. Salutary effect of gastric pentadecapeptide BPC 157 in two different stress urinary incontinence models in female rats

    PubMed Central

    Jandric, Ivan; Vrcic, Hrvoje; Balen, Marica Jandric; Kolenc, Danijela; Brcic, Luka; Radic, Bozo; Drmic, Domagoj; Seiwerth, Sven; Sikiric, Predrag

    2013-01-01

    Background Since an originally anti-ulcer stable gastric pentadecapeptide BPC 157 (PL 14736) was shown to promote healing of injured striated muscle and smooth muscle in the gastrointestinal tract, we explored its therapeutic potentials for leak point pressure (LPP) recovery in rat stress urinary incontinence (SUI) after transabdominal urethrolysis (TU) and prolonged vaginal dilatation (VD). Material/Methods During a 7-day period, TU-rats and VD-rats (or healthy rats) received BPC 157, either (i) intraperitoneally, 10 μg/kg or 10 ng/kg, once daily (first administration 30 min after surgery, last 24 h before LPP-testing and sacrifice), or (ii) per-orally, 10 μg/kg in drinking water (0.16 μg/mL, 12 mL/rat/day). Vesicourethral segments were harvested for immunohistochemical evaluation. Results All BPC 157 regimens counteracted decrease of LPP values in TU-rats and VD-rats. Additionally, BPC 157-TU rats (μg-intraperitoneally or per-orally) and BPC 157-VD rats (μg intraperitoneally) reached LPP values originally noted in healthy rats. Conversely, in healthy rats, BPC 157 did not alter LPP. Immunohistochemical studies revealed higher desmin (delineates striated organization of skeletal muscle), smooth muscle actin, and CD34 (angiogenic marker) positivity within the urethral wall in BPC 157-treated rats vs. controls, as well as overall preserved muscle/connective tissue ratio assessed with Mallory’s trichrome staining. Conclusions Pentadecapeptide BPC 157, applied parenterally or per-orally, appears to ameliorate the SUI in rat models, improving the otherwise detrimental course of healing after VD and TU, which may be analogous to human injury. These beneficial effects may possibly be selectively used in future strategies for treatment of SUI. PMID:23478678

  14. Redistribution of Gαs in Mouse Salivary Glands Following β-Adrenergic Stimulation

    PubMed Central

    Hand, Arthur R.; Elder, Kareen O.; Norris, Rachael P.

    2015-01-01

    Objective Signaling via β-adrenergic receptors activates heterotrimeric G-proteins, which dissociate into α and βγ subunits. In salivary glands, the α subunit of Gs stimulates adenylate cyclase, increasing cyclic AMP levels and promoting exocytosis. The goals of this study were to determine Gαs localization in salivary glands and whether it undergoes redistribution upon activation. Methods Mouse parotid and submandibular (SMG) glands were fixed with paraformaldehyde and prepared for immunofluorescence labeling with anti-Gαs. Results In unstimulated parotid and SMG acinar cells, Gαs was localized mainly to basolateral membranes. Some parotid acinar cells also exhibited cytoplasmic fluorescence. Isoproterenol (IPR) stimulation resulted in decreased membrane fluorescence and increased cytoplasmic fluorescence, which appeared relatively uniform by 30 min. Beginning about 2 hr after IPR, cytoplasmic fluorescence decreased and membrane fluorescence increased, approaching unstimulated levels in SMG acini by 4 hr. Some parotid acini exhibited cytoplasmic fluorescence up to 8 hr after IPR. The IPR-induced redistribution of Gαs was prevented (SMG) or reduced (parotid) by prior injection of propranolol. Striated duct cells of unstimulated mice exhibited general cytoplasmic fluorescence, which was unchanged after IPR. Conclusions Gαs is localized to basolateral membranes of unstimulated salivary acinar cells. Activation of Gαs causes its release from the cell membrane and movement into the cytoplasm. Reassociation of Gαs with the membrane begins about 2 hr after stimulation in the SMG, but complete reassociation takes several hours in the parotid gland. The presence of Gαs in striated duct cells suggests a role in signal transduction of secretion and/or electrolyte transport processes. PMID:25748393

  15. Endopolyploidy Changes with Age-Related Polyethism in the Honey Bee, Apis mellifera

    PubMed Central

    Rangel, Juliana; Strauss, Kim; Seedorf, Kaileah; Hjelmen, Carl E.; Johnston, J. Spencer

    2015-01-01

    Honey bees (Apis mellifera) exhibit age polyethism, whereby female workers assume increasingly complex colony tasks as they age. While changes in DNA methylation accompany age polyethism, other DNA modifications accompanying age polyethism are less known. Changes in endopolyploidy (DNA amplification in the absence of cell division) with increased larval age are typical in many insect cells and are essential in adults for creating larger cells, more copies of essential loci, or greater storage capacity in secretory cells. However, changes in endopolyploidy with increased adult worker age and polyethism are unstudied. In this study, we examined endopolyploidy in honey bee workers ranging in age from newly emerged up to 55 days old. We found a nonsignificant increase in ploidy levels with age (P < 0.1) in the most highly endopolyploid secretory cells, the Malpighian tubules. All other cell types decreased ploidy levels with age. Endopolyploidy decreased the least amount (nonsignificant) in neural (brain) cells and the stinger (P < 0.1). There was a significant reduction of endopolyploidy with age in leg (P < 0.05) and thoracic (P < 0.001) muscles. Ploidy in thoracic muscle dropped from an average of 0.5 rounds of replication in newly emerged workers to essentially no rounds of replication (0.125) in the oldest workers. Ploidy reduction in flight muscle cells is likely due to the production of G1 (2C) nuclei by amitotic division in the multinucleate striated flight muscles that are essential to foragers, the oldest workers. We suggest that ploidy is constrained by the shape, size and makeup of the multinucleate striated muscle cells. Furthermore, the presence of multiple 2C nuclei might be optimal for cell function, while higher ploidy levels might be a dead-end strategy of some aging adult tissues, likely used to increase cell size and storage capacity in secretory cells. PMID:25881205

  16. Shatter cone and microscopic shock-alteration evidence for a post-Paleoproterozoic terrestrial impact structure near Santa Fe, New Mexico, USA

    NASA Astrophysics Data System (ADS)

    Fackelman, Siobhan P.; Morrow, Jared R.; Koeberl, Christian; McElvain, Thornton H.

    2008-06-01

    Field mapping, morphologic description, and petrographic analysis of recently discovered shatter cones within Paleoproterozoic crystalline rocks exposed over an area > 5 km 2, located ˜ 8 km northeast of Santa Fe, New Mexico, USA, give robust evidence of a previously unrecognized terrestrial impact structure. Herein, we provisionally name this the "Santa Fe impact structure". The shatter cones are composed of nested sub-conical, curviplanar, and flat joint surfaces bearing abundant curved and bifurcating striations that strongly resemble the multiply striated joint surfaces (MSJS) documented from shatter cones at Vredefort dome. The cones occur as a penetrative feature in intrusive igneous and supracrustal metamorphic rocks, are unusually large (up to 2 m long and 0.5 m wide at the base), display upward-pointing apices, and have subvertical, northeastward-plunging axes that crosscut regional host-rock fabrics. Key characteristics of superficially similar, but non-shock-generated conical and striated features are inconsistent with the properties of the Santa Fe cones. In thin section, sub-millimeter-scale, dark, semi-opaque to isotropic veneers on cone surfaces and veinlets within cone interiors closely resemble previously described shock-induced melt features. Microscopic grain alteration, restricted generally to within 1 mm of the cone surfaces, includes random fractures, fluid micro-inclusions, sericite replacement in feldspar, rare kink bands in mica, optical mosaicism, and decorated planar fractures (PFs) and planar deformation features (PDFs) in quartz. The PFs and PDFs are dominated by a basal (0001) crystallographic orientation, which indicate a peak shock pressure of ˜ 5-10 GPa that is consistent with shatter cone formation. Regional structural and exhumation models, together with anomalous breccia units that overlie and crosscut the shatter cone-bearing rocks, may provide additional age constraints for the impact event. The observed shatter cone outcrop

  17. Myf5 and Myogenin in the development of thymic myoid cells - Implications for a murine in vivo model of myasthenia gravis.

    PubMed

    Hu, Bo; Simon-Keller, Katja; Küffer, Stefan; Ströbel, Philipp; Braun, Thomas; Marx, Alexander; Porubsky, Stefan

    2016-03-01

    Myasthenia gravis (MG) is caused by autoantibodies against the neuromuscular junction of striated muscle. Most MG patients have autoreactive T- and B-cells directed to the acetylcholine receptor (AChR). To achieve immunologic tolerance, developing thymocytes are normally eliminated after recognition of self-antigen-derived peptides. Presentation of muscle-specific antigens is likely achieved through two pathways: on medullary thymic epithelial cells and on medullary dendritic cells cross-presenting peptides derived from a unique population of thymic myoid cells (TMC). Decades ago, it has been hypothesized that TMC play a key role in the induction of immunological tolerance towards skeletal muscle antigens. However, an experimental model to address this postulate has not been available. To generate such a model, we tested the hypothesis that the development of TMC depends on myogenic regulatory factors. To this end, we utilized Myf5-deficient mice, which lack the first wave of muscle cells but form normal skeletal muscles later during development, and Myogenin-deficient mice, which fail to form differentiated myofibers. We demonstrate for the first time that Myf5- and Myogenin-deficient mice showed a partial or complete, respectively, loss of TMC in an otherwise regularly structured thymus. To overcome early postnatal lethality of muscle-deficient, Myogenin-knockout mice we transplanted Myogenin-deficient fetal thymuses into Foxn1(nu/nu) mice that lack their own thymus anlage. We found that the transplants are functional but lack TMC. In combination with established immunization strategies (utilizing AChR or Titin), this model should enable us in the future testing the hypothesis that TMC play an indispensable role in the development of central tolerance towards striated muscle antigens. PMID:26708556

  18. Characterization of Esophageal Physiology Using Mechanical State Analysis.

    PubMed

    Leibbrandt, Richard E; Dinning, Phil G; Costa, Marcello; Cock, Charles; Wiklendt, Lukasz; Wang, Guangsong; Tack, Jan; van Beckevoort, Dirk; Rommel, Nathalie; Omari, Taher I

    2016-01-01

    The esophagus functions to transport swallowed fluids and food from the pharynx to the stomach. The esophageal muscles governing bolus transport comprise circular striated muscle of the proximal esophagus and circular smooth muscle of the distal esophagus. Longitudinal smooth muscle contraction provides a mechanical advantage to bolus transit during circular smooth muscle contraction. Esophageal striated muscle is directly controlled by neural circuits originating in the central nervous system, resulting in coordinated contractions. In contrast, the esophageal smooth muscle is controlled by enteric circuits modulated by extrinsic central neural connections resulting in neural relaxation and contraction. The esophageal muscles are modulated by sensory information arising from within the lumen. Contraction or relaxation, which changes the diameter of the lumen, alters the intraluminal pressure and ultimately inhibits or promotes flow of content. This relationship that exists between the changes in diameter and concurrent changes in intraluminal pressure has been used previously to identify the "mechanical states" of the circular muscle; that is when the muscles are passively or actively, relaxing or contracting. Detecting these changes in the mechanical state of the muscle has been difficult and as the current interpretation of esophageal motility is based largely upon pressure measurement (manometry), subtle changes in the muscle function during peristalsis can be missed. We hypothesized that quantification of mechanical states of the esophageal circular muscles and the pressure-diameter properties that define them, would allow objective characterization of the mechanisms that govern esophageal peristalsis. To achieve this we analyzed barium swallows captured by simultaneous videofluoroscopy and pressure with impedance recording. From these data we demonstrated that intraluminal impedance measurements could be used to determine changes in the internal diameter of

  19. The Musculature of Coleoid Cephalopod Arms and Tentacles.

    PubMed

    Kier, William M

    2016-01-01

    The regeneration of coleoid cephalopod arms and tentacles is a common occurrence, recognized since Aristotle. The complexity of the arrangement of the muscle and connective tissues of these appendages make them of great interest for research on regeneration. They lack rigid skeletal elements and consist of a three-dimensional array of muscle fibers, relying on a type of skeletal support system called a muscular hydrostat. Support and movement in the arms and tentacles depends on the fact that muscle tissue resists volume change. The basic principle of function is straightforward; because the volume of the appendage is essentially constant, a decrease in one dimension must result in an increase in another dimension. Since the muscle fibers are arranged in three mutually perpendicular directions, all three dimensions can be actively controlled and thus a remarkable diversity of movements and deformations can be produced. In the arms and tentacles of coleoids, three main muscle orientations are observed: (1) transverse muscle fibers arranged in planes perpendicular to the longitudinal axis; (2) longitudinal muscle fibers typically arranged in bundles parallel to the longitudinal axis; and (3) helical or obliquely arranged layers of muscle fibers, arranged in both right- and left-handed helixes. By selective activation of these muscle groups, elongation, shortening, bending, torsion and stiffening of the appendage can be produced. The predominant muscle fiber type is obliquely striated. Cross-striated fibers are found only in the transverse muscle mass of the prey capture tentacles of squid and cuttlefish. These fibers have unusually short myofilaments and sarcomeres, generating the high shortening velocity required for rapid elongation of the tentacles. It is likely that coleoid cephalopods use ultrastructural modifications rather than tissue-specific myosin isoforms to tune contraction velocities. PMID:26925401

  20. E-box sites and a proximal regulatory region of the muscle creatine kinase gene differentially regulate expression in diverse skeletal muscles and cardiac muscle of transgenic mice.

    PubMed Central

    Shield, M A; Haugen, H S; Clegg, C H; Hauschka, S D

    1996-01-01

    Previous analysis of the muscle creatine kinase (MCK) gene indicated that control elements required for transcription in adult mouse muscle differed from those required in cell culture, suggesting that distinct modes of muscle gene regulation occur in vivo. To examine this further, we measured the activity of MCK transgenes containing E-box and promoter deletions in a variety of striated muscles. Simultaneous mutation of three E boxes in the 1,256-bp MCK 5' region, which abolished transcription in muscle cultures, had strikingly different effects in mice. The mutations abolished transgene expression in cardiac and tongue muscle and caused a reduction in expression in the soleus muscle (a muscle with many slow fibers) but did not affect expression in predominantly fast muscles: quadriceps, abdominals, and extensor digitorum longus. Other regulatory sequences with muscle-type-specific activities were found within the 358-bp 5'-flanking region. This proximal region conferred relatively strong expression in limb and abdominal skeletal muscles but was inactive in cardiac and tongue muscles. However, when the 206-bp 5' enhancer was ligated to the 358-bp region, high levels of tissue-specific expression were restored in all muscle types. These results indicate that E boxes and a proximal regulatory region are differentially required for maximal MCK transgene expression in different striated muscles. The overall results also imply that within skeletal muscles, the steady-state expression of the MCK gene and possibly other muscle genes depends on transcriptional mechanisms that differ between fast and slow fibers as well as between the anatomical and physiological attributes of each specific muscle. PMID:8756664

  1. Sequential myosin phosphorylation activates tarantula thick filament via a disorder-order transition.

    PubMed

    Espinoza-Fonseca, L Michel; Alamo, Lorenzo; Pinto, Antonio; Thomas, David D; Padrón, Raúl

    2015-08-01

    Phosphorylation of myosin regulatory light chain (RLC) N-terminal extension (NTE) activates myosin in thick filaments. RLC phosphorylation plays a primary regulatory role in smooth muscles and a secondary (modulatory) role in striated muscles, which is regulated by Ca(2+)via TnC/TM on the thin filament. Tarantula striated muscle exhibits both regulatory systems: one switches on/off contraction through thin filament regulation, and another through PKC constitutively Ser35 phosphorylated swaying free heads in the thick filaments that produces quick force on twitches regulated from 0 to 50% and modulation is accomplished recruiting additional force-potentiating free and blocked heads via Ca(2+)4-CaM-MLCK Ser45 phosphorylation. We have used microsecond molecular dynamics (MD) simulations of tarantula RLC NTE to understand the structural basis for phosphorylation-based regulation in tarantula thick filament activation. Trajectory analysis revealed that an inter-domain salt bridge network (R39/E58,E61) facilitates the formation of a stable helix-coil-helix (HCH) motif formed by helices P and A in the unphosphorylated NTE of both myosin heads. Phosphorylation of the blocked head on Ser45 does not induce any substantial structural changes. However, phosphorylation of the free head on Ser35 disrupts this salt bridge network and induces a partial extension of helix P along RLC helix A. While not directly participating in the HCH folding, phosphorylation of Ser35 unlocks a compact structure and allows the NTE to spontaneously undergo coil-helix transitions. The modest structural change induced by the subsequent Ser45 diphosphorylation monophosphorylated Ser35 free head facilitates full helix P extension into a single structurally stable α-helix through a network of intra-domain salt bridges (pS35/R38,R39,R42). We conclude that tarantula thick filament activation is controlled by sequential Ser35-Ser45 phosphorylation via a conserved disorder-to-order transition. PMID

  2. The myogenic electric organ of Sternopygus macrurus: a non-contractile tissue with a skeletal muscle transcriptome

    PubMed Central

    Samanta, Manoj P.; Chaidez, Alexander

    2016-01-01

    In most electric fish species, the electric organ (EO) derives from striated muscle cells that suppress many muscle properties. In the gymnotiform Sternopygus macrurus, mature electrocytes, the current-producing cells of the EO, do not contain sarcomeres, yet they continue to make some cytoskeletal and sarcomeric proteins and the muscle transcription factors (MTFs) that induce their expression. In order to more comprehensively examine the transcriptional regulation of genes associated with the formation and maintenance of the contractile sarcomere complex, results from expression analysis using qRT-PCR were informed by deep RNA sequencing of transcriptomes and miRNA compositions of muscle and EO tissues from adult S. macrurus. Our data show that: (1) components associated with the homeostasis of the sarcomere and sarcomere-sarcolemma linkage were transcribed in EO at levels similar to those in muscle; (2) MTF families associated with activation of the skeletal muscle program were not differentially expressed between these tissues; and (3) a set of microRNAs that are implicated in regulation of the muscle phenotype are enriched in EO. These data support the development of a unique and highly specialized non-contractile electrogenic cell that emerges from a striated phenotype and further differentiates with little modification in its transcript composition. This comprehensive analysis of parallel mRNA and miRNA profiles is not only a foundation for functional studies aimed at identifying mechanisms underlying the transcription-independent myogenic program in S. macrurus EO, but also has important implications to many vertebrate cell types that independently activate or suppress specific features of the skeletal muscle program. PMID:27114860

  3. Background and stimulus-induced patterns of high metabolic activity in the visual cortex (area 17) of the squirrel and macaque monkey

    SciTech Connect

    Humphrey, A.L.; Hendrickson, A.E.

    1983-02-01

    We have used 2-deoxy-D-(/sup 14/C)glucose (2-DG) autoradiography and cytochrome oxidase histochemistry to examine background and stimulus-induced patterns of metabolic activity in monkey striate cortex. In squirrel monkeys (Saimiri sciureus) that binocularly or monocularly viewed diffuse white light or binocularly viewed bars of many orientations and spatial frequencies, 2-DG consumption was not uniform across the cortex but consisted of regularly spaced radial zones of high uptake. The zones extended through all laminae except IVc beta and, when viewed tangentially, formed separate patches 500 microns apart. The cytochrome oxidase stain in these animals also revealed patches of high metabolism which coincided with the 2-DG patches. Squirrel monkeys binocularly viewing vertical stripes showed parallel bands of increased 2-DG uptake in the cortex, while the cytochrome label in these animals remained patchy. When monkeys were kept in the dark during 2-DG exposure, 2-DG-labeled patches were not seen but cytochrome oxidase-positive patches remained. In macaque (Macaca nemestrina) monkeys, binocular stimulation with many orientations and spatial frequencies produced radial zones of high 2-DG uptake in layers I to IVa and VI. When viewed tangentially, these zones formed a dots-in-rows pattern with a spacing of 350 X 500 microns; cytochrome oxidase staining produced an identical pattern. Macaca differed from Saimiri in that monocular stimulation labeled alternate rows. These results indicate that there are radial zones of high background metabolism across squirrel and macaque monkey striate cortex. In Saimiri these zones do not appear to be related to an eye dominance system, while in Macaca they do. The presence of these zones of high metabolism may complicate the interpretation of 2-DG autoradiographs that result from specific visual stimuli.

  4. Sequential Myosin Phosphorylation Activates Tarantula Thick Filament via a Disorder-Order Transition

    PubMed Central

    Espinoza-Fonseca, L. Michel; Alamo, Lorenzo; Pinto, Antonio; Thomas, David D.; Padrón, Raúl

    2015-01-01

    Phosphorylation of myosin regulatory light chain (RLC) N-terminal extension (NTE) activates myosin in thick filaments. RLC phosphorylation plays a primary regulatory role in smooth muscle and a secondary (modulatory) role in striated muscle, which is regulated by Ca2+ via TnC/TM on the thin filament. Tarantula striated muscle exhibits both regulatory systems: one switches on/off contraction through thin filament regulation, and another through PKC constitutively Ser35 phosphorylated swaying free heads in the thick filaments that produces quick force on twitches regulated from 0 to 50% and modulation is accomplished recruiting additional force-potentiating free and blocked heads via Ca2+4-CaM-MLCK Ser45 phosphorylation. We have used microsecond molecular dynamics (MD) simulations of tarantula RLC NTE to understand the structural basis for phosphorylation-based regulation in tarantula thick filament activation. Trajectories analysis revealed that an inter-domain salt bridges network (R39/E58,E61) facilitates formation of a stable helix-coil-helix (HCH) motif made up by helices P and A in the unphosphorylated NTE of both myosin heads. Phosphorylation of blocked head on Ser45 does not induce any substantial structural change. However, phosphorylation of free head on Ser35 disrupts this salt bridge network and induces a partial extension of helix P along RLC helix A. While not directly participating in the HCH inter-domain folding, phosphorylation of Ser35 unlocks compact structure and allows the NTE to spontaneously undergo coil-helix transitions. The modest structural change induced by subsequent Ser45 diphosphorylation monophosphorylated Ser35 free head, facilitates full helix P extension into a single structurally stable α-helix through a network of intra-domain salt bridges (pS35/R38,R39,R42). We conclude that tarantula thick filament activation is controlled by sequential Ser35-Ser45 phosphorylation via a conserved disorder-to-order transition. PMID:26038232

  5. Pituitary adenylate cyclase-activating polypeptide enhances saliva secretion via direct binding to PACAP receptors of major salivary glands in mice.

    PubMed

    Matoba, Yuko; Nonaka, Naoko; Takagi, Yoshitoki; Imamura, Eisaku; Narukawa, Masayuki; Nakamachi, Tomoya; Shioda, Seiji; Banks, William A; Nakamura, Masanori

    2016-09-01

    Xerostomia, or dry mouth, is a common syndrome that is generally treated with artificial saliva; however, no other effective methods have yet been established. Saliva secretion is mainly under the control of the autonomic nervous system. Pituitary adenylate cyclase-activating polypeptide (PACAP) is recognized as a multifunctional neuropeptide in various organs. In this study, we examined the effect of PACAP on saliva secretion, and detected the distribution of the PACAP type 1 receptor (PAC1R) in major salivary glands, including the parotid, submandibular, and sublingual glands, in 9-week-old male C57BL/6 mice. Intranasal administration of PACAP 38 increased the amount of saliva secreted, which was not inhibited by atropine pretreatment. Immunohistochemical analysis showed that PAC1R was distributed in the three major salivary glands. In the parotid and sublingual glands, PAC1R was detected in striated duct cells, whereas in the submandibular gland, a strong PAC1R immunoreaction was detected in tall columnar epithelial cells in the granular ducts (i.e., pillar cells), as well as in some striated duct cells. PACAP significantly increased the concentration of epidermal growth factor in saliva. These results suggest that PACAP directly regulates saliva secretion by controlling the absorption activity in the ducts, and that pillar cells regulate the function of granular epithelial cells in the granular duct, such as the secretion of growth factors into the saliva. Collectively, these results suggest the possibility of PACAP as a new effective treatment of xerostomia. Anat Rec, 299:1293-1299, 2016. © 2016 Wiley Periodicals, Inc. PMID:27339371

  6. Distribution of H type 1 and of H type 2 antigens of ABO blood group in different cells of human submandibular gland.

    PubMed

    Liu, Y H; Fujitani, N; Koda, Y; Kimura, H

    1998-01-01

    We have examined the immunohistochemical distribution of H Type 1 and of H Type 2 substances of the ABO blood group system in human submandibular gland using either of the two anti-H monoclonal antibodies MAb 1E3 and MAb 3A5. MAb 3A5 was specific for H Type 2, and MAb 1E3 reacted with each of H Type 1-H Type 4 artificial antigens. We have developed a competitive inhibition method against H Type 2 and have obtained MAb 1E3, which is fairly specific for H Type 1 under certain conditions. Mucous cells from secretors were strongly stained by 1E3 and weakly by 3A5, whereas those from nonsecretors showed no reaction with 1E3 and 3A5. Serous cells from both secretors and nonsecretors were stained neither by 1E3 nor by 3A5. Striated and interlobular duct cells were strongly stained by 1E3 and by 3A5, regardless of the secretor status. These results indicated that the expressions of the H Type 1 and H Type 2 in different cell types of the submandibular gland were controlled by different genes. In addition, we have determined the acceptor specificity of two alpha(1,2)fucosyltransferases (H and Se enzymes) after transient expressions of the FUT1 and FUT2 in COS7 cells, and found that the H enzyme activity was similar for both Type 1 and Type 2 precursors, and that Se enzyme activity with the Type 1 precursor was higher than that with the Type 2 precursor. Expression of the H Type 1 antigen in mucous cells was found to be dependent on the Se gene, whereas expressions of the H Type 1 and H Type 2 antigens in striated and interlobular duct cells were dependent on the H gene. (J Histochem Cytochem 46:69-76, 1998) PMID:9405495

  7. Cellular and humoral immune abnormalities in Gulf War veterans.

    PubMed Central

    Vojdani, Aristo; Thrasher, Jack D

    2004-01-01

    We examined 100 symptomatic Gulf War veterans (patients) and 100 controls for immunologic assays. The veterans and controls were compared for the percentage of T cells (CD3); B cells (CD19); helper:suppressor (CD4:CD8) ratio; natural killer (NK) cell activity; mitogenic response to phytohemagglutin (PHA) and pokeweed mitogen (PWM); level of immune complexes; myelin basic protein (MBP) and striated and smooth muscle autoantibodies; and antibodies against Epstein-Barr virus, cytomegalovirus, herpes simplex virus type 1 (HSV-1), HSV-2, human herpes Type 6 (HHV-6), and Varicella zoster virus (VZV). The percentage of T cells in patients versus controls was not significantly different, whereas a significantly higher proportion of patients had elevated T cells compared with controls. The percentage of B cells was significantly elevated in the patients versus the controls. The NK cell (NK) activity was significantly decreased in the patients (24.8 +/- 16.5 lytic units) versus the controls (37.3 +/- 26.4 lytic units). The percentage of patients with lower than normal response to PHA and PWM was significantly different from controls. Immune complexes were significantly increased in the patients (53.1 +/- 18.6, mean +/- SD) versus controls (34.6 +/- 14.3). Autoantibody titers directed against MBP and striated or smooth muscle were significantly greater in patients versus controls. Finally, the patients had significantly greater titers of antibodies to the viruses compared with the controls (p < 0.001). These immune alterations were detected 2-8 years after participation in the Gulf War. The immune alterations are consistent with exposure to different environmental factors. We conclude that Gulf War syndrome is a multifaceted illness with immune function alterations that may be induced by various factors and are probably associated with chronic fatigue syndrome. PMID:15175170

  8. [Pollen morphology in species of Canna (Cannaceae), and systematics implications].

    PubMed

    Ciciarelli, María de las Mercedes; Passarelli, Lilian M; Rolleri, Cristina H

    2010-03-01

    The morphology of pollen grains of eight taxa of Canna, C. ascendens, C. coccinea, C compacta, C. glauca, C. indica, C. paniculata, C. variegatifolia and C. fuchsina, an unpublished new species, were studied using light and scanning electronic microscopes. We used the Wodehouse technique on samples of 20 grains per specimen to measure the intine with a light microscope; and the density of spines (in 400 microm2 fields) with scanning electronic microscopy. Pollen grains are spherical, echinate, omniaperturate. The sporoderm presents a very thin exine covering a thicker intine. Corrugate micro-perforate, sub-reticulate, rugate, rugulate, striate to folded, micro-striate, micro-granulate, and smooth types of the external surface of the sporoderm were found. The spines consist of exine, partially to completely covered by tryphine. The two-layered intine is the thicker part of the wall. Echinate ornamentation is a generic character in Canna, but size, surface and color of pollen walls, and density and shape of spines, are diagnostic for species. Pollen morphology supports the view of C. indica and C. coccinea as different species. Canna fuchsina grows in wild, dense colonies, in humid riverside forests from Buenos Aires and Santa Fe Provinces, Argentina; its characters suggest relationships with a not well known group of taxa, some of them hybrids, such as C. x generalis. However, as these plants showed normal, well formed grains, close to those of C. coccinea, that germinate over the stigmatic surfaces in fresh flowers, we decided to include their pollen in this study. PMID:20411707

  9. Independent specialisation of myosin II paralogues in muscle vs. non-muscle functions during early animal evolution: a ctenophore perspective

    PubMed Central

    2012-01-01

    Background Myosin II (or Myosin Heavy Chain II, MHCII) is a family of molecular motors involved in the contractile activity of animal muscle cells but also in various other cellular processes in non-muscle cells. Previous phylogenetic analyses of bilaterian MHCII genes identified two main clades associated respectively with smooth/non-muscle cells (MHCIIa) and striated muscle cells (MHCIIb). Muscle cells are generally thought to have originated only once in ancient animal history, and decisive insights about their early evolution are expected to come from expression studies of Myosin II genes in the two non-bilaterian phyla that possess muscles, the Cnidaria and Ctenophora. Results We have uncovered three MHCII paralogues in the ctenophore species Pleurobrachia pileus. Phylogenetic analyses indicate that the MHCIIa / MHCIIb duplication is more ancient than the divergence between extant metazoan lineages. The ctenophore MHCIIa gene (PpiMHCIIa) has an expression pattern akin to that of "stem cell markers" (Piwi, Vasa…) and is expressed in proliferating cells. We identified two MHCIIb genes that originated from a ctenophore-specific duplication. PpiMHCIIb1 represents the exclusively muscular form of myosin II in ctenophore, while PpiMHCIIb2 is expressed in non-muscle cells of various types. In parallel, our phalloidin staining and TEM observations highlight the structural complexity of ctenophore musculature and emphasize the experimental interest of the ctenophore tentacle root, in which myogenesis is spatially ordered and strikingly similar to striated muscle formation in vertebrates. Conclusion MHCIIa expression in putative stem cells/proliferating cells probably represents an ancestral trait, while specific involvement of some MHCIIa genes in smooth muscle fibres is a uniquely derived feature of the vertebrates. That one ctenophore MHCIIb paralogue (PpiMHCIIb2) has retained MHCIIa-like expression features furthermore suggests that muscular expression of the

  10. Vredefort shatter cones revisited

    NASA Astrophysics Data System (ADS)

    Nicolaysen, L. O.; Reimold, W. U.

    1999-03-01

    Shatter cones have been described from a number of circular and polygonal structures worldwide, the origin of which has been alternatively ascribed to the impacts of large extraterrestrial projectiles or to catastrophic endogenic processes. Despite their association with enigmatic, catastrophic processes, the nature of shatter cones and the physics involved in their formation have not been comprehensively researched. Results of detailed field and laboratory studies of shatter cones from three areas in the collar of the Vredefort Dome in South Africa are presented. Vredefort shatter cones are directly related to a widely displayed fracture phenomenon, termed ``multiply striated joint sets (MSJS)''. MSJs are planar to curviplanar fractures occuring at spacings of <1 to several millimeters. The joint sets have a fractal character. When a new measurement protocol is used in the field, involving study of all joint surfaces and all steps and striae exposed on these surfaces, new information is gained on the genesis and significance of the MSJS and on their relationship to striated conical fractures. The internal constitution of a rock specimen with MSJS was examined in detail, by documenting the precise geometry of many fractures in a suite of parallel thin sections transecting the specimen. The steps and striae on shatter cone surfaces have the characteristics of displacement fractures (microfaults), along which evidence of melting is observed. Shatter cone and MSJS surfaces are often covered with glassy films; we evaluate whether these fracture phenomena are linked to the formation of pseudotachylitic (friction) melt. Our field and petrographic observations can be interpreted as consistent with the generation of shatter cones/MSJS relatively late in the formation of the Vredefort structure. This scenario contrasts sharply with the widely held view that shatter cones are formed during the early ``compression'' phase of a shock event that affected horizontal strata.

  11. Dissecting Oceanic Detachment Faults: Fault Zone Geometry, Deformation Mechanisms, and Nature of Fluid-Rock Interactions

    NASA Astrophysics Data System (ADS)

    Bonnemains, D.; Escartin, J.; Verlaguet, A.; Andreani, M.; Mevel, C.

    2015-12-01

    To understand the extreme strain localization at long-lived oceanic detachment faults rooting deeply below the axis, we present results of geological investigations at the 13°19'N detachment along the Mid-Atlantic Ridge, conducted during the ODEMAR cruise (Nov-Dec13, NO Pourquoi Pas?) with ROV Victor6000 (IFREMER). During this cruise we investigated and sampled the corrugated fault to understand its geometry, nature of deformation, and links to fluid flow. We identified and explored 7 fault outcrops on the flanks of microbathymetric striations subparallel to extension. These outcrops expose extensive fault planes, with the most prominent ones extending 40-90m laterally, and up to 10 m vertically. These fault surfaces systematically show subhorizontal striations subparallel to extension, and define slabs of fault-rock that are flat and also striated at sample scale. Visual observations show a complex detachment fault zone, with anastomosing fault planes at outcrop scale (1-10 m), with a highly heterogeneous distribution of deformation. We observe heterogeneity in fault-rock nature at outcrop scale. In situ samples from striated faults are primarily basalt breccias with prior green-schist facies alteration, and a few ultramafic fault-rocks that show a complex deformation history, with early schistose textures, brittlely reworked as clasts within the fault. The basalt breccias show variable silicification and associated sulfides, recording important fluid-rock interactions during exhumation. To understand the link between fluid and deformation during exhumation, we will present microstructural observation of deformation textures, composition, and distribution and origin of quartz and sulfides, as well as constraints on the temperature of silicifying fluids from fluid inclusions in quartz. These results allow us to characterize in detail the detachment fault zone geometry, and investigate the timing of silicification relative to deformation.

  12. A discrepancy within primate spatial vision and its bearing on the definition of edge detection processes in machine vision

    NASA Technical Reports Server (NTRS)

    Jobson, Daniel J.

    1990-01-01

    The visual perception of form information is considered to be based on the functioning of simple and complex neurons in the primate striate cortex. However, a review of the physiological data on these brain cells cannot be harmonized with either the perceptual spatial frequency performance of primates or the performance which is necessary for form perception in humans. This discrepancy together with recent interest in cortical-like and perceptual-like processing in image coding and machine vision prompted a series of image processing experiments intended to provide some definition of the selection of image operators. The experiments were aimed at determining operators which could be used to detect edges in a computational manner consistent with the visual perception of structure in images. Fundamental issues were the selection of size (peak spatial frequency) and circular versus oriented operators (or some combination). In a previous study, circular difference-of-Gaussian (DOG) operators, with peak spatial frequency responses at about 11 and 33 cyc/deg were found to capture the primary structural information in images. Here larger scale circular DOG operators were explored and led to severe loss of image structure and introduced spatial dislocations (due to blur) in structure which is not consistent with visual perception. Orientation sensitive operators (akin to one class of simple cortical neurons) introduced ambiguities of edge extent regardless of the scale of the operator. For machine vision schemes which are functionally similar to natural vision form perception, two circularly symmetric very high spatial frequency channels appear to be necessary and sufficient for a wide range of natural images. Such a machine vision scheme is most similar to the physiological performance of the primate lateral geniculate nucleus rather than the striate cortex.

  13. The Musculature of Coleoid Cephalopod Arms and Tentacles

    PubMed Central

    Kier, William M.

    2016-01-01

    The regeneration of coleoid cephalopod arms and tentacles is a common occurrence, recognized since Aristotle. The complexity of the arrangement of the muscle and connective tissues of these appendages make them of great interest for research on regeneration. They lack rigid skeletal elements and consist of a three-dimensional array of muscle fibers, relying on a type of skeletal support system called a muscular hydrostat. Support and movement in the arms and tentacles depends on the fact that muscle tissue resists volume change. The basic principle of function is straightforward; because the volume of the appendage is essentially constant, a decrease in one dimension must result in an increase in another dimension. Since the muscle fibers are arranged in three mutually perpendicular directions, all three dimensions can be actively controlled and thus a remarkable diversity of movements and deformations can be produced. In the arms and tentacles of coleoids, three main muscle orientations are observed: (1) transverse muscle fibers arranged in planes perpendicular to the longitudinal axis; (2) longitudinal muscle fibers typically arranged in bundles parallel to the longitudinal axis; and (3) helical or obliquely arranged layers of muscle fibers, arranged in both right- and left-handed helixes. By selective activation of these muscle groups, elongation, shortening, bending, torsion and stiffening of the appendage can be produced. The predominant muscle fiber type is obliquely striated. Cross-striated fibers are found only in the transverse muscle mass of the prey capture tentacles of squid and cuttlefish. These fibers have unusually short myofilaments and sarcomeres, generating the high shortening velocity required for rapid elongation of the tentacles. It is likely that coleoid cephalopods use ultrastructural modifications rather than tissue-specific myosin isoforms to tune contraction velocities. PMID:26925401

  14. Cortical processing of global form, motion and biological motion under low light levels.

    PubMed

    Burton, Eliza; Wattam-Bell, John; Rubin, Gary S; Atkinson, Janette; Braddick, Oliver; Nardini, Marko

    2016-04-01

    Advances in potential treatments for rod and cone dystrophies have increased the need to understand the contributions of rods and cones to higher-level cortical vision. We measured form, motion and biological motion coherence thresholds and EEG steady-state visual evoked potentials (SSVEP) responses under light conditions ranging from photopic to scotopic. Low light increased thresholds for all three kinds of stimuli; however, global form thresholds were relatively more impaired than those for global motion or biological motion. SSVEP responses to coherent global form and motion were reduced in low light, and motion responses showed a shift in topography from the midline to more lateral locations. Contrast sensitivity measures confirmed that basic visual processing was also affected by low light. However, comparison with contrast sensitivity function (CSF) reductions achieved by optical blur indicated that these were insufficient to explain the pattern of results, although the temporal properties of the rod system may also play a role. Overall, mid-level processing in extra-striate areas is differentially affected by light level, in ways that cannot be explained in terms of low-level spatiotemporal sensitivity. A topographical shift in scotopic motion SSVEP responses may reflect either changes to inhibitory feedback mechanisms between V1 and extra-striate regions or a reduction of input to the visual cortex. These results provide insight into how higher-level cortical vision is normally organised in absence of cone input, and provide a basis for comparison with patients with cone dystrophies, before and after treatments aiming to restore cone function. PMID:26878697

  15. Upper Cisuralian palynology and palaeoclimate of Manuguru area Godavari basin, India and their global correlation

    NASA Astrophysics Data System (ADS)

    K, Pauline Sabina; Jha, Neerja

    2014-10-01

    The Permian system of the Palaeozoic Erathem is divided into three series, the Early Permian Cisuralian Series, the Middle Permian Guadalupian Series, and the Late Permian Lopingian Series. The Cisuralian Series encompasses the Asselian to Kungurian stages which constitute the basal part of the Gondwana supersequence I. In India, they are represented lithostratigraphically by the Talchir, Karharbari, and Barakar formations. This paper presents the palynological results from the Barakar Formation of the Upper Cisuralian Series from Manuguru which lies in the southeastern part of the Godavari basin. The succession studied comprises 35 subsurface samples from bore hole 1007 represented by clay, shale, sandstone, and coal. The palynofloras in this sequence have a homogenous composition demonstrating that not many significant floral changes took place through the considered stratigraphic range. The entire sequence is characterized by the dominance of nonstriate bisaccate genus Scheuringipollenites and sub-dominance of striate bisaccate genus Faunipollenites(= Protohaploxypinus). The other pollen genera among the nonstriate bisaccates are Rhizomaspora, Primuspollenites, Ibisporites, and Platysaccus. The striate bisaccates include Striatites, Striatopodocarpites, and Stroterosporites. The taeniate taxa are represented by Lueckisporites and Lunatisporites. The common monosaccate genera include Caheniasaccites, Potoniesporites, and Barakarites. Spores are less common and include Latosporites, Brevitriletes, Horriditriletes, Microbaculispora, and Callumispora. They characterize the palynofloral composition of the Lower Barakar Formation. The correlation of this assemblage with some of the biostratigraphic palynozones proposed previously for the Cisuralian sequences of the Paraná Basin of South America, Kalahari Karoo Basin of South Africa, Ruhuhu Basin of Tanzania, East Africa as well as palynoassemblages from South Victoria Land and Dronning Maud Land, Antarctica and

  16. Permian-Triassic palynostratigraphy in Mailaram area, Godavari Graben, Andhra Pradesh, India

    NASA Astrophysics Data System (ADS)

    Jha, Neerja; Aggarwal, Neha

    2012-10-01

    Palynological investigations of five borecores, viz., GAM-3, GAM-6, GAM-7, GAM-8 and GAM-10 from Mailaram area have suggested the occurrence of complete Lower Gondwana succession in Mailaram area. Total nine palynozones have been identified on the basis of dominance, sub-dominance and appearance of various palynotaxa. These palynozones belong to Talchir, Upper Karharbari and Barakar (Early Permian), Raniganj (Late Permian) and Panchet (Early Triassic) palynofloras of Indian Gondwana. The oldest Palynozone-1 demonstrated in borecore GAM-6 (331.4-500 m) and borecore GAM-10 (505.66-581.55 m), is characterized by the dominance of Parasaccites and sub-dominance of Plicatipollenites belongs to Talchir Palynoflora; Palynozone-2 identified in borecore GAM-7 (667-749 m) and borecore GAM-8 (89.75 m) is characterized by the dominance of Parasaccites and sub-dominance of Scheuringipollenites which belongs to Upper Karharbari Palynoflora. Palynozone-3, identified in borecore GAM-6 (149.7-240.05 m) and borecore GAM-8 (84.95 m), is characterized by the dominance of Scheuringipollenites akin to Scheuringipollenites zone of Barakar palynoflora; Palynozone-4, recorded in borecores GAM-3 (294-437.98 m), GAM-7 (453-640.5 m) and GAM-8 (35.35 m) is characterized by the dominance of Faunipollenites and sub-dominance of Striatopodocarpites along with certain stratigraphically significant taxa, viz., Weylandites, Guttulapollenites, Corisaccites, Aurangapollenites and Osmundacidites. Palynozone-5, demarcated in borecore GAM-3 (144.86-221.3 m) and borecore GAM-10 (35.35 m), is distinguished by the dominance of striate disaccates along with at least 30% pollen assigned to Striasulcites; Palynozone-6, identified in borecore GAM-3 (35.1-73.08 m) and borecore GAM-7 (231-423 m), is characterized by the dominance of striate disaccates along with 20-30% of Densipollenites; Palynozone-7, recorded in borecore GAM-7 (206 m), is distinguished by the dominance of Crescentipollenites along with striate

  17. Five new species of the genus Tripylella (Nematoda: Enoplida: Tripylidae).

    PubMed

    Prado-Vera, Ignacio Cid Del; Ferris, Howard; Nadler, Steven A

    2016-01-01

    Five new species of the genus Tripylella are described, two from México, one from Fátima, Portugal, one from Quito, Ecuador, and one from California, USA. Tripylella mexicana sp. n. is characterized by its short body (average 0.74 mm), short pharynx (average 161 μm), short tail (average 117 μm), presence of an excretory pore and small setae distributed sparsely along the body, the presence of body pores, the posterior position of the subventral teeth in relation to the small dorsal tooth with all teeth in contiguous stomal chambers, the finely-striated cuticle with many anastomoses, the non-protruding vulval lips, and the presence of sclerotized pieces in the vulval region. Tripylella muscusi sp. n. is characterized by its body length (average 0.94 mm), pharynx length (average 201 μm), tail length (average 140 μm), the anterior position of the subventral teeth in relation to the small dorsal tooth in a single stomal chamber, the presence of an excretory pore, the presence of body pores and sparse somatic setae, the finely-striated cuticle with sparse anastomoses, protruding vulval lips and sclerotized oval-shaped pieces present in the vulval region. Tripylella quitoensis sp. n. is characterized by the short body length (average 0.72 mm), the short outer labial setae, the short pharynx (average 175 μm), the location of the anterior subventral teeth and posterior dorsal tooth in the same stomal chamber, the short tail (average 98 μm), the apparent absence of an excretory pore, presence of body pores, presence of somatic setae, a finely-striated cuticle, non-protruding vulval lips, and very small oval sclerotized pieces in the vulva. Tripylella fatimaensis sp. n. is characterized by the short body, (average 0.74 mm) long, by the length of the pharynx (average 180 μm), the length of the tail (average 110 μm) and in the length of its reduced diameter portion, 45-58 μm, the presence of an excretory pore, body pores and three pairs of caudal setae (one pair

  18. Activation of Visuomotor Systems during Visually Guided Movements: A Functional MRI Study

    NASA Astrophysics Data System (ADS)

    Ellermann, Jutta M.; Siegal, Joel D.; Strupp, John P.; Ebner, Timothy J.; Ugurbil, Kâmil

    1998-04-01

    The dorsal stream is a dominant visuomotor pathway that connects the striate and extrastriate cortices to posterior parietal areas. In turn, the posterior parietal areas send projections to the frontal primary motor and premotor areas. This cortical pathway is hypothesized to be involved in the transformation of a visual input into the appropriate motor output. In this study we used functional magnetic resonance imaging (fMRI) of the entire brain to determine the patterns of activation that occurred while subjects performed a visually guided motor task. In nine human subjects, fMRI data were acquired on a 4-T whole-body MR system equipped with a head gradient coil and a birdcage RF coil using aT*2-weighted EPI sequence. Functional activation was determined for three different tasks: (1) a visuomotor task consisting of moving a cursor on a screen with a joystick in relation to various targets, (2) a hand movement task consisting of moving the joystick without visual input, and (3) a eye movement task consisting of moving the eyes alone without visual input. Blood oxygenation level-dependent (BOLD) contrast-based activation maps of each subject were generated using period cross-correlation statistics. Subsequently, each subject's brain was normalized to Talairach coordinates, and the individual maps were compared on a pixel by pixel basis. Significantly activated pixels common to at least four out of six subjects were retained to construct the final functional image. The pattern of activation during visually guided movements was consistent with the flow of information from striate and extrastriate visual areas, to the posterior parietal complex, and then to frontal motor areas. The extensive activation of this network and the reproducibility among subjects is consistent with a role for the dorsal stream in transforming visual information into motor behavior. Also extensively activated were the medial and lateral cerebellar structures, implicating the cortico

  19. H5N1 surveillance in migratory birds in Java, Indonesia.

    PubMed

    Stoops, Arthur C; Barbara, Katie A; Indrawan, Mochamad; Ibrahim, Ima N; Petrus, Wicaksana B; Wijaya, Susan; Farzeli, Arik; Antonjaya, Ungke; Sin, Lim W; Hidayatullah, N; Kristanto, Ige; Tampubolon, A M; Purnama, S; Supriatna, Adam; Burgess, Timothy H; Williams, Maya; Putnam, Shannon D; Tobias, Steve; Blair, Patrick J

    2009-12-01

    We sought to elucidate the role of migratory birds in transmission of H5N1 in an enzoonotic area. Resident, captive, and migratory birds were sampled at five sites in Java, Indonesia. Mist nets were used to trap birds. Birds were identified to species. RNA was extracted from swabs and reverse transcriptase polymerase chain reaction (RT-PCR) conducted for the HA and M genes of H5N1. Antibodies were detected by enzyme-linked immunosorbent assay and hemagglutination inhibition test. Between October 2006 and September 2007, a total of 4,067 captive, resident, and migratory birds comprising 98 species in 23 genera were sampled. The most commonly collected birds were the common sandpiper (6% of total), striated heron (3%), and the domestic chicken (14%). The overall prevalence of H5N1 antibodies was 5.3%. A significantly higher percentage of captive birds (16.1%) showed antibody evidence of H5N1 exposure when compared to migratory or resident birds. The greatest number of seropositive birds in each category were Muschovy duck (captive), striated heron (resident), and the Pacific golden plover (migratory). Seven apparently well captive birds yielded molecular evidence of H5N1 infection. Following amplification, the HA, NA, and M genes were analyzed. Phylogenetic analysis of the HA gene showed that the isolates were 97% similar to EU124153.1 A/chicken/West Java/Garut May 2006, an isolate obtained in a similar region of West Java. While no known markers of neuraminidase inhibitor resistance were found within the NA gene, M segment analysis revealed the V27A mutation known to confer resistance to adamantanes. Our results demonstrate moderate serologic evidence of H5N1 infection in captive birds, sampled in five sites in Java, Indonesia, but only occasional infection in resident and migratory birds. These data imply that in an enzoonotic region of Indonesia the role of migratory birds in transmission of H5N1 is limited. PMID:19271996

  20. Kingdom protozoa and its 18 phyla.

    PubMed

    Cavalier-Smith, T

    1993-12-01

    The demarcation of protist kingdoms is reviewed, a complete revised classification down to the level of subclass is provided for the kingdoms Protozoa, Archezoa, and Chromista, and the phylogenetic basis of the revised classification is outlined. Removal of Archezoa because of their ancestral absence of mitochondria, peroxisomes, and Golgi dictyosomes makes the kingdom Protozoa much more homogeneous: they all either have mitochondria and peroxisomes or have secondarily lost them. Predominantly phagotrophic, Protozoa are distinguished from the mainly photosynthetic kingdom Chromista (Chlorarachniophyta, Cryptista, Heterokonta, and Haptophyta) by the absence of epiciliary retronemes (rigid thrust-reversing tubular ciliary hairs) and by the lack of two additional membranes outside their chloroplast envelopes. The kingdom Protozoa has two subkingdoms: Adictyozoa, without Golgi dictyosomes, containing only the phylum Percolozoa (flagellates and amoeboflagellates); and Dictyozoa, made up of 17 phyla with Golgi dictyosomes. Dictyozoa are divided into two branches: (i) Parabasalia, a single phylum with hydrogenosomes and 70S ribosomes but no mitochondria, Golgi dictyosomes associated with striated roots, and a kinetid of four or five cilia; and (ii) Bikonta (16 unicellular or plasmodial phyla with mitochondria and bikinetids and in which Golgi dictyosomes are not associated with striated ciliary roots), which are divided into two infrakingdoms: Euglenozoa (flagellates with discoid mitochondrial cristae and trans-splicing of miniexons for all nuclear genes) and Neozoa (15 phyla of more advanced protozoa with tubular or flat [usually nondiscoid] mitochondrial cristae and cis-spliced spliceosomal introns). Neozoa are divided into seven parvkingdoms: (i) Ciliomyxa (three predominantly ciliated phyla with tubular mitochondrial cristae but no cortical alveoli, i.e., Opalozoa [flagellates with tubular cristae], Mycetozoa [slime molds], and Choanozoa [choanoflagellates, with

  1. Expression profiles of inhibitor of growth protein 2 in normal and cancer tissues: An immunohistochemical screening analysis.

    PubMed

    Zhao, Shuang; Yang, Xue-Feng; Gou, Wen-Feng; Lu, Hang; Li, Hua; Zhu, Zhi-Tu; Sun, Hong-Zhi; Zheng, Hua-Chuan

    2016-02-01

    Inhibitor of growth protein 2 (ING2) has an important role in the regulation of chromatin remodeling, cell proliferation, cell‑cycle arrest, senescence and apoptosis. The present study performed an immunohistochemical analysis for expression profiling of ING2 protein in an array of tissues comprising normal mouse and human tissues, as well as human hepatocellular (n=62), renal clear cell (n=62), pancreatic (n=62), esophageal squamous cell (n=45), cervical squamous cell (n=31), breast (n=144), gastric (n=196), colorectal (n=96), ovarian (n=208), endometrial (n=96) and lung (n=192) carcinoma tissues. In mouse tissues, ING2 was detected in the nuclei and cytoplasm of the glandular epithelium of breast, hepatocytes, intestine, bronchium and alveoli, as well as the squamous epithelium of skin and glomeruli, and in myocardial cells, while it was located in the cytoplasm of renal tubules and striated muscle cells. ING2 protein was scattered in the brain and spleen. In human tissues, ING2 protein was principally distributed in the cytoplasm, while in it was present in the cytoplasm and nuclei in the stomach, intestine, cervix, endometrium trachea, breast and pancreas. The nuclear location of ING2 in the stomach was more prominent than that in the cytoplasm. High ING2 immunoreactivity was detected in the tongue, stomach, skin, pancreas, cervix and breast, whereas weakly in the brain stem, thymus, thyroid, lung, striated muscle, testis, bladder and ovary. In total, 617 out of 1,194 of the tested cancer tissues (51.7%) were ING2-positive. In most cases, ING2 expression was found to be restricted to the cytoplasm of all cancer tissues, while in certain cancer types, including renal clear cell, ovarian and colorectal carcinoma, it was occasionally present in the nuclei. Among the cancer tissues examined, ING2 was most frequently expressed in breast cancer (67.4%) and gynecological cancer types, including ovarian cancer (61.5%) and endometrial cancer (57.3%). Compared with

  2. Preserved Flora and Organics in Impact Melt Breccias: Implications for Capturing Past Life on Mars

    NASA Astrophysics Data System (ADS)

    Schultz, P. H.; Harris, R. S.; Clemett, S.; Thomas-Keprta, K.

    2013-12-01

    At least seven impact glass-bearing deposits have been documented in the Argentine stratigraphy, each recording separate events between the Holocene and late Miocene [1,2]. Detailed evidence for their origin by impact includes: planar deformation features (PDFs in quartz, feldspars, pyroxene, olivine, etc.), asymmetric isotropization (i.e., alternate-twin deformation) in plagioclase, diaplectic phases, ultra-high temperature melting (e.g., lechatelierite, molten rutile) and decomposition (e.g., baddeleyite), and quench textures around minerals, e.g., beta-crystobalite, etc. [1-3]. Incorporation of materials from depth indicates that this was not an airburst but a series of crater-forming impacts. Many hand samples also contain relicts of extant biota. Scanning electron microprobe (SEM) images reveal preservation of delicate forms including: striated layers between vesicular impact glass and parallel vein-like features at higher magnification. The striated patterns resemble vascular bundles of the mesophyll (ground tissue) of a plant. Identifiable parts of the plant anatomy, e.g. papillae and cell walls, contain skeletal magnetite crystals and high-temperature, i.e., phases indicating that vitreous fossilization occurred at extremely high temperatures and rapid quench rates. The morphology is generally similar to contemporary regional grasses (pampas grass) including small spherules (papilla). The intricate forms (20nm to 20mm) indicate features rapidly preserved rather than simple impressions. Reaction zones (vesiculation and quenched minerals) along the interface between the melt and entrained plants indicate rapid quenching. Compositional mapping reveals the presence of insignificant levels of carbon, but chemical analyses confirm the high silica content (> 60%). Various analytical techniques (micro-Raman, TEM/SEM, and μltra-L2MS) further reveal the preserved organic materials, including tetracyclic pyrrolines, essential members of the group of porphyrin species

  3. Alcohol differentially alters extracellular matrix and adhesion molecule expression in skeletal muscle and heart

    PubMed Central

    Steiner, Jennifer L.; Pruznak, Anne M.; Navaratnarajah, Maithili; Lang, Charles H.

    2015-01-01

    Background The production of fibrosis in response to chronic alcohol abuse is well recognized in liver but has not been fully characterized in striated muscle and may contribute to functional impairment. Therefore, the purpose of this study was to use an unbiased discovery-based approach to determine the effect of chronic alcohol consumption on the expression profile of genes important for cell-cell and cell-extracellular matrix (ECM) interactions in both skeletal and cardiac muscle. Methods Adult male rats were pair-fed an alcohol-containing liquid diet or control diet for 24 wks, and skeletal muscle (gastrocnemius) and heart collected in the freely fed state. A pathway-focused gene expression PCR array was performed on these tissues to assess mRNA content for 84 ECM proteins, and selected proteins were confirmed by Western analysis. Results In gastrocnemius, alcohol feeding up-regulated expression of 11 genes and down-regulated expression of 1 gene. Alcohol increased fibrosis as indicated by increased mRNA and/or protein for collagen α1(I), α2(I), α1(III) and α2(IV) as well as hydroxyproline. Alcohol also increased α-smooth muscle actin protein, an index of myofibroblast activation, but no concomitant change in TGF-β was detected. The mRNA and protein content for other ECM components, such as integrin α-5, L-selectin, PECAM, Sparc and Adamts2 was also increased by alcohol. Only laminin α-3 mRNA was decreased in gastrocnemius from alcohol-fed rats, while 66 ECM- or cell adhesion-related mRNAs were unchanged by alcohol. For heart, expression of 16 genes was up-regulated, expression of 3 genes was down-regulated, and 65 mRNAs were unchanged by alcohol; there were no common alcohol-induced gene expression changes between heart and skeletal muscle. Finally, alcohol increased TNFα and IL-12 mRNA in both skeletal and cardiac muscle, but IL-6 mRNA was increased and IL-10 mRNA decreased only in skeletal muscle. Conclusions These data demonstrate a fibrotic

  4. Increased anal basal pressure in chronic anal fissures may be caused by overreaction of the anal-external sphincter continence reflex.

    PubMed

    van Meegdenburg, Maxime M; Trzpis, Monika; Heineman, Erik; Broens, Paul M A

    2016-09-01

    Chronic anal fissure is a painful disorder caused by linear ulcers in the distal anal mucosa. Even though it counts as one of the most common benign anorectal disorders, its precise etiology and pathophysiology remains unclear. Current thinking is that anal fissures are caused by anal trauma and pain, which leads to internal anal sphincter hypertonia. Increased anal basal pressure leads to diminished anodermal blood flow and local ischemia, which delays healing and leads to chronic anal fissure. The current treatment of choice for chronic anal fissure is either lateral internal sphincterotomy or botulinum toxin injections. In contrast to current thinking, we hypothesize that the external, rather than the internal, anal sphincter is responsible for increased anal basal pressure in patients suffering from chronic anal fissure. We think that damage to the anal mucosa leads to hypersensitivity of the contact receptors of the anal-external sphincter continence reflex, resulting in overreaction of the reflex. Overreaction causes spasm of the external anal sphincter. This in turn leads to increased anal basal pressure, diminished anodermal blood flow, and ischemia. Ischemia, finally, prevents the anal fissure from healing. Our hypothesis is supported by two findings. The first concerned a chronic anal fissure patient with increased anal basal pressure (170mmHg) who had undergone lateral sphincterotomy. Directly after the operation, while the submucosal anesthetic was still active, basal anal pressure decreased to 80mmHg. Seven hours after the operation, when the anesthetic had completely worn off, basal anal pressure increased again to 125mmHg, even though the internal anal sphincter could no longer be responsible for the increase. Second, in contrast to previous studies, recent studies demonstrated that botulinum toxin influences external anal sphincter activity and, because it is a striated muscle relaxant, it seems reasonable to presume that it affects the striated

  5. Characterization of muscle contraction with second harmonic generation microscopy

    NASA Astrophysics Data System (ADS)

    Prent, Nicole

    Muscle cells have the ability to change length and generate force due to orchestrated action of myosin nanomotors that cause sliding of actin filaments along myosin filaments in the sarcomeres, the fundamental contractile units, of myocytes. The correlated action of hundreds of sarcomeres is needed to produce the myocyte contractions. This study probes the molecular structure of the myofilaments and investigates the movement correlations between sarcomeres during contraction. In this study, second harmonic generation (SHG) microscopy is employed for imaging striated myocytes. Myosin filaments in striated myocytes inherently have a nonzero second-order susceptibility, [special characters omitted] and therefore generate efficient SHG. Employing polarization-in polarization-out (PIPO) SHG microscopy allows for the accurate determination of the characteristic ratio, [special characters omitted] in birefringent myocytes, which describes the structure of the myosin filament. Analysis shows that the b value at the centre of the myosin filament, where the nonlinear dipoles are better aligned, is slightly lower than the value at the edges of the filament, where there is more disorder in orientation of the nonlinear dipoles from the myosin heads. Forced stretching of myocytes resulted in an SHG intensity increase with the elongation of the sarcomere. SHG microscopy captured individual sarcomeres during contraction, allowing for the measurement of sarcomere length (SL) and SHG intensity (SI) fluctuations. The fluctuations also revealed higher SHG intensity in elongated sarcomeres. The sarcomere synchronization model (SSM) for contracting and quiescent myocytes was developed, and experimentally verified for three cases (isolated cardiomyocyte, embryonic chicken cardiomyocyte, and larva myocyte). During contraction, the action of SLs and SIs between neighbouring sarcomeres partially correlated, whereas in quiescent myocytes the SLs show an anti-correlation and the SIs have no

  6. Fast muscle in squid (Loligo pealei): contractile properties of a specialized muscle fibre type.

    PubMed

    Kier, William M; Curtin, Nancy A

    2002-07-01

    The contractile properties of the transverse muscle of the tentacles and the transverse muscle of the arms of the squid Loligo pealei were investigated using small muscle fibre bundle preparations. In addition, transmission electron microscopy was used to measure the length of the thick myofilaments of the two muscle fibre types. The thick filament length of the cross-striated tentacle fibres was 0.81+/-0.08 microm (mean +/- S.D, N=51) while that of the obliquely striated arm muscle fibres was 7.41+/-0.44 microm (N=58). The difference in thick filament length of the two muscle types was predicted to result in a much higher shortening velocity of the tentacle muscle compared with the arm muscle. This was tested by investigating the force/velocity relationship for isotonic shortening of the two muscle types. Fitting Hill's equation to the results gave a maximum shortening velocity (V(max), the intercept on the velocity axis) of 15.4+/-1.0 L(0) s(-1) (mean +/- S.D., N=9) for the tentacle fibres and of 1.5+/-0.2 L(0) s(-1) (N=8) for the arm fibres, where L(0) is the length at which peak isometric force was recorded. The difference in thick filament length was also predicted to result in lower peak tension in the tentacle versus the arm muscle. For the tentacle, the mean peak tetanic tension during a brief isometric tetanus (0.2s) of 131+/-56 mN mm(-2) cross-sectional area (mean +/- S.D., N=12) was observed at a stimulus frequency of 80 Hz, whereas the mean peak tetanic tension of the arm fibres during a brief isometric tetanus (0.2s) was 468+/-91 mN mm(-2) (N=5) and was observed at a stimulus frequency of 160 Hz. The length/force relationships (expressed relative to L(0)) of the two muscle types were similar. The ratio of twitch force to peak tetanic force was 0.66 in the tentacle fibres, but only 0.03 in the arm fibres. PMID:12077167

  7. Kingdom protozoa and its 18 phyla.

    PubMed Central

    Cavalier-Smith, T

    1993-01-01

    The demarcation of protist kingdoms is reviewed, a complete revised classification down to the level of subclass is provided for the kingdoms Protozoa, Archezoa, and Chromista, and the phylogenetic basis of the revised classification is outlined. Removal of Archezoa because of their ancestral absence of mitochondria, peroxisomes, and Golgi dictyosomes makes the kingdom Protozoa much more homogeneous: they all either have mitochondria and peroxisomes or have secondarily lost them. Predominantly phagotrophic, Protozoa are distinguished from the mainly photosynthetic kingdom Chromista (Chlorarachniophyta, Cryptista, Heterokonta, and Haptophyta) by the absence of epiciliary retronemes (rigid thrust-reversing tubular ciliary hairs) and by the lack of two additional membranes outside their chloroplast envelopes. The kingdom Protozoa has two subkingdoms: Adictyozoa, without Golgi dictyosomes, containing only the phylum Percolozoa (flagellates and amoeboflagellates); and Dictyozoa, made up of 17 phyla with Golgi dictyosomes. Dictyozoa are divided into two branches: (i) Parabasalia, a single phylum with hydrogenosomes and 70S ribosomes but no mitochondria, Golgi dictyosomes associated with striated roots, and a kinetid of four or five cilia; and (ii) Bikonta (16 unicellular or plasmodial phyla with mitochondria and bikinetids and in which Golgi dictyosomes are not associated with striated ciliary roots), which are divided into two infrakingdoms: Euglenozoa (flagellates with discoid mitochondrial cristae and trans-splicing of miniexons for all nuclear genes) and Neozoa (15 phyla of more advanced protozoa with tubular or flat [usually nondiscoid] mitochondrial cristae and cis-spliced spliceosomal introns). Neozoa are divided into seven parvkingdoms: (i) Ciliomyxa (three predominantly ciliated phyla with tubular mitochondrial cristae but no cortical alveoli, i.e., Opalozoa [flagellates with tubular cristae], Mycetozoa [slime molds], and Choanozoa [choanoflagellates, with

  8. Movement preparation and execution: differential functional activation patterns after traumatic brain injury.

    PubMed

    Gooijers, Jolien; Beets, Iseult A M; Albouy, Genevieve; Beeckmans, Kurt; Michiels, Karla; Sunaert, Stefan; Swinnen, Stephan P

    2016-09-01

    Years following the insult, patients with traumatic brain injury often experience persistent motor control problems, including bimanual coordination deficits. Previous studies revealed that such deficits are related to brain structural white and grey matter abnormalities. Here, we assessed, for the first time, cerebral functional activation patterns during bimanual movement preparation and performance in patients with traumatic brain injury, using functional magnetic resonance imaging. Eighteen patients with moderate-to-severe traumatic brain injury (10 females; aged 26.3 years, standard deviation = 5.2; age range: 18.4-34.6 years) and 26 healthy young adults (15 females; aged 23.6 years, standard deviation = 3.8; age range: 19.5-33 years) performed a complex bimanual tracking task, divided into a preparation (2 s) and execution (9 s) phase, and executed either in the presence or absence of augmented visual feedback. Performance on the bimanual tracking task, expressed as the average target error, was impaired for patients as compared to controls (P < 0.001) and for trials in the absence as compared to the presence of augmented visual feedback (P < 0.001). At the cerebral level, movement preparation was characterized by reduced neural activation in the patient group relative to the control group in frontal (bilateral superior frontal gyrus, right dorsolateral prefrontal cortex), parietal (left inferior parietal lobe) and occipital (right striate and extrastriate visual cortex) areas (P's < 0.05). During the execution phase, however, the opposite pattern emerged, i.e. traumatic brain injury patients showed enhanced activations compared with controls in frontal (left dorsolateral prefrontal cortex, left lateral anterior prefrontal cortex, and left orbitofrontal cortex), parietal (bilateral inferior parietal lobe, bilateral superior parietal lobe, right precuneus, right primary somatosensory cortex), occipital (right striate and extrastriate visual cortices), and

  9. Numerical Modeling of Shatter Cones Development in Impact Craters

    NASA Technical Reports Server (NTRS)

    Baratoux, D.; Melosh, H. J.

    2003-01-01

    Shatter cones are the characteristic forms of rock fractures in impact structures. They have been used for decades as unequivocal fingerprints of meteoritic impacts on Earth. The abundant data about shapes, apical angles, sizes and distributions of shatter cones for many terrestrial impact structures should provide insights for the determination of impact conditions and characteristics of shock waves produced by high-velocity projectiles in geologic media. However, previously proposed models for the formation of shatter cones do not agree with observations. For example, the widely accepted Johnson-Talbot mechanism requires that the longitudinal stress drops to zero between the arrival of the elastic precursor and the main plastic wave. Unfortunately, observations do not support such a drop. A model has been also proposed to explain the striated features on the surface of shatter cones but can not invoked for their conical shape. The mechanism by which shatter cones form thus remains enigmatic to date. In this paper we present a new model for the formation of shatter cones. Our model has been tested by means of numerical simulations using the hydrocodes SALE 2D enhanced with the Grady-Kipp-Melosh fragmentation model.

  10. Visual circuits of the avian telencephalon: evolutionary implications

    NASA Technical Reports Server (NTRS)

    Shimizu, T.; Bowers, A. N.

    1999-01-01

    Birds and primates are vertebrates that possess the most advanced, efficient visual systems. Although lineages leading to these two classes were separated about 300 million years ago, there are striking similarities in their underlying neural mechanisms for visual processing. This paper discusses such similarities with special emphasis on the visual circuits in the avian telencephalon. These similarities include: (1) the existence of two parallel visual pathways and their distinct telencephalic targets, (2) anatomical and functional segregation within the visual pathways, (3) laminar organization of the telencephalic targets of the pathways (e.g. striate cortex in primates), and (4) possible interactions between multiple visual areas. Additional extensive analyses are necessary to determine whether these similarities are due to inheritance from a common ancestral stock or the consequences of convergent evolution based on adaptive response to similar selective pressures. Nevertheless, such a comparison is important to identify the general and specific principles of visual processing in amniotes (reptiles, birds, and mammals). Furthermore, these principles in turn will provide a critical foundation for understanding the evolution of the brain in amniotes.

  11. Expression of Muscle-Specific Ribosomal Protein L3-Like Impairs Myotube Growth.

    PubMed

    Chaillou, Thomas; Zhang, Xiping; McCarthy, John J

    2016-09-01

    The ribosome has historically been considered to have no cell-specific function but rather serve in a "housekeeping" capacity. This view is being challenged by evidence showing that heterogeneity in the protein composition of the ribosome can lead to the functional specialization of the ribosome. Expression profiling of different tissues revealed that ribosomal protein large 3-like (Rpl3l) is exclusively expressed in striated muscle. In response to a hypertrophic stimulus, Rpl3l expression in skeletal muscle was significantly decreased by 82% whereas expression of the ubiquitous paralog Rpl3 was significantly increased by ∼fivefold. Based on these findings, we developed the hypothesis that Rpl3l functions as a negative regulator of muscle growth. To test this hypothesis, we used the Tet-On system to express Rpl3l in myoblasts during myotube formation. In support of our hypothesis, RPL3L expression significantly impaired myotube growth as assessed by myotube diameter (-23%) and protein content (-14%). Further analysis showed that the basis of this impairment was caused by a significant decrease in myoblast fusion as the fusion index was significantly lower (-17%) with RPL3L expression. These findings are the first evidence to support the novel concept of ribosome specialization in skeletal muscle and its role in the regulation of skeletal muscle growth. J. Cell. Physiol. 231: 1894-1902, 2016. © 2015 Wiley Periodicals, Inc. PMID:26684695

  12. Primary culture of venom glands from the Brazilian armed spider, Phoneutria nigriventer (Araneae, Ctenidae).

    PubMed

    Silva, Luciana Maria; Lages, Carolina Pereira; Venuto, Thiago; Lima, Rebeca Mascarenhas; Diniz, Marcelo Vasconcellos; Valentim, Cláudia L Lage; Baba, Elio Hideo; Pimenta, Paulo Filemon P; Fortes-Dias, Consuelo L

    2008-03-01

    Phoneutria spider venoms are a rich source of bioactive components. The limited amounts of crude material available, however, can be considered as a major hindrance for a faster development in the field. In the present study, we attempted to establish primary cultures of venom glands of Phoneutria nigriventer as an alternative, in vitro source of venom. Three different developmental stages were tried as starting materials: whole embryo (inside the cocoon), nymph (early after cocoon hatching) and young adult (1 year after cocoon hatching). The embryonic cells remained in suspension in the primary cultures, with no signs of adhesion or differentiation, for about 6 months. Nevertheless, this culture was useful for the first chromosome C-banding of Phoneutria. An average of 29+/-1 acrocentric chromosomes were found. Striated muscle cells were the only kind of cells in the culture of venom glands from Phoneutria nymphs. The most promising results were achieved with 1-year-old specimens. Besides muscle, adherent epithelial cells were also obtained in culture. Although these cells remained in culture for a short time (up to 48 h) immunochemical analysis of the culture supernatant evidenced the presence of Phoneutria venom components. This can be considered as a first step toward the functional cultures of venom glands of Phoneutria spiders. PMID:18068746

  13. Fine Structure and Molecular Phylogeny of Parametopidium circumlabens (Ciliophora: Armophorea), Endocommensal of Sea Urchins.

    PubMed

    da Silva-Neto, Inácio Domingos; da Silva Paiva, Thiago; do Nascimento Borges, Bárbara; Harada, Maria Lúcia

    2016-01-01

    Metopid armophoreans are ciliates commonly found in anaerobic environments worldwide; however, very little is known of their fine structure. In this study, the metopid Parametopidium circumlabens (Biggar and Wenrich 1932) Aescht, 1980, a common endocommensal of sea urchins, is investigated for the first time with emphasis on transmission electron microscopy, revealing several previously unknown elements of its morphology. Somatic dikinetids of P. circumlabens have a typical ribbon of transverse microtubules, an isolated microtubule near triplets 4 and 5 of the anterior kinetosome, plus two other microtubules between anterior and posterior kinetosomes, a short kinetodesmal striated fiber and long postciliary microtubules. In the dikinetids of the perizonal stripe, the kinetodesmal fiber is very pronounced, and there is a conspicuous microfibrillar network system associated with the kinetosomes. A new structure, shaped as a dense, roughly cylindrical mass surrounded by microtubules, is found associated with the posterior kinetosome of perizonal dikinetids. The paroral membrane is diplostichomonad and the adoral membranelles are of the "paramembranelle" type. Bayesian inference and maximum-likelihood analysis of the 18S-rDNA gene unambiguously placed P. circumlabens as sister group of the cluster formed by ((Atopospira galeata, Atopospira violacea) Metopus laminarius) + Clevelandellida, corroborating its classification within the Metopida. PMID:26111546

  14. Tumor-targeting Salmonella typhimurium A1-R in combination with doxorubicin eradicate soft tissue sarcoma in a patient-derived orthotopic xenograft (PDOX) model

    PubMed Central

    Murakami, Takashi; DeLong, Jonathan; Eilber, Fritz C.; Zhao, Ming; Zhang, Yong; Zhang, Nan; Singh, Arun; Russell, Tara; Deng, Samantha; Reynoso, Jose; Quan, Cuong; Hiroshima, Yukihiko; Matsuyama, Ryusei; Chishima, Takashi; Tanaka, Kuniya; Bouvet, Michael; Chawla, Sant; Endo, Itaru; Hoffman, Robert M.

    2016-01-01

    A patient with high grade undifferentiated pleomorphic soft-tissue sarcoma from a striated muscle was grown orthotopically in the right biceps femoris muscle of mice to establish a patient-derived orthotopic xenograft (PDOX) model. Twenty PDOX mice were divided into 4 groups: G1, control without treatment; G2, Salmonella typhimurium (S. typhimurium)A1-R administered by intratumoral (i.t.) injection once a week for 4 weeks; G3, doxorubicin (DOX) administered by intraperitoneal (i.p.) injection once a week for 4 weeks; G4, S. typhimurium A1-R (i.t.) administered once a week for 2 weeks followed by i.p. doxorubicin once a week for 2 weeks. On day 25 from the initiation of treatment, tumor volume in G2, G3, and G4 was significantly lower than G1. Mice found without gross tumor included one mouse (20%) in G2; one mouse (20%) in G3; and 3 mice (60%) in G4. Body weight loss did not significantly differ between the 3 treated groups or from the untreated control. Histological examination revealed eradication of tumor only in G4 where mice were treated with S. typhimurium A1-R followed by DOX. Our present study indicates future clinical potential of combining S. typhimurium A1-R with chemotherapy such as DOX for soft tissue sarcoma patients. PMID:26859573

  15. [Early diagnosis of tubal pregnancy with vaginal sonography].

    PubMed

    Schurz, B; Wenzl, R; Eppel, W; Söregi, G; Reinold, E

    1989-07-01

    In 19 patients, the transvaginal (TVU) and in 24 patients, the transabdominal (TAU) ultrasound approaches were compared in their ability to identify by visualization the adnexal mass of ectopic pregnancy. The direct visualization of ectopic pregnancy (EUP) was 25% in TAU and 94.7% in TVU approach (p 0.03). All women had a proven EUP in laparoscopy. TAU approach showed a significant inferiority (p 0.02) and TVU a significant superiority (p 0.08) in comparison to palpation. 83% out of 43 women had spotting. Unspecific signs for EUP, like retrouterine fluid, was seen in 20.9%. Striated endometrium was seen in 6.9%, in 37.2% the thickness of endometrium was less than 10 mm, in 55.8% more than 10 mm. A pseudogestationsac was detected in 6.9%, corpus luteum formation in 27.2%. With vaginosonography, organs can be seen at close range, and the specific signs of EUP, an extrauterine ring-formation surrounded by a dam-like structure of the tube, was identified in 94.7%. PMID:2476361

  16. The UNC-45 Myosin Chaperone: From Worms to Flies to Vertebrates

    PubMed Central

    Lee, Chi F.; Melkani, Girish C.; Bernstein, Sanford I.

    2014-01-01

    UNC-45 is a UCS domain protein that is critical for myosin stability and function. It likely aides in folding myosin during cellular differentiation and maintenance and protects myosin from denaturation during stress. Invertebrates have a single unc-45 gene that is expressed in both muscle and non-muscle tissues. Vertebrates possess one gene expressed in striated muscle (unc-45b) and one that is more generally expressed (unc-45a). Structurally, UNC-45 is composed of a series of alpha-helices connected by loops. It has an N-terminal TPR domain that binds to Hsp90 and a central domain composed of armadillo repeats. Its C-terminal UCS domain, which is also comprised of helical armadillo repeats, interacts with myosin. In this review, we present biochemical, structural and genetic analyses of UNC-45 in Caenorhabditis elegans, Drosophila melanogaster and various vertebrates. Further, we provide insights into UNC-45 functions, its potential mechanism of action and its roles in human disease. PMID:25376491

  17. Targeted homozygous deletion of M-band titin in cardiomyocytes prevents sarcomere formation.

    PubMed

    Musa, Hanny; Meek, Stephen; Gautel, Mathias; Peddie, Dianna; Smith, Andrew J H; Peckham, Michelle

    2006-10-15

    Titin, a multifunctional protein that stretches from the Z-disk to the M-band in heart and skeletal muscle, contains a kinase domain, phosphorylation sites and multiple binding sites for structural and signalling proteins in the M-band. To determine whether this region is crucial for normal sarcomere development, we created mouse embryonic stem cell (ES) lines in which either one or both alleles contained a targeted deletion of the entire M-band-coding region, leaving Z-disk-binding and myosin-filament-binding sites intact. ES cells were differentiated into cardiomyocytes, and myofibrillogenesis investigated by immunofluorescence microscopy. Surprisingly, deletion of one allele did not markedly affect differentiation into cardiomyocytes, suggesting that a single intact copy of the titin gene is sufficient for normal myofibrillogenesis. By contrast, deletion of both alleles resulted in a failure of differentiation beyond an early stage of myofibrillogenesis. Sarcomeric myosin remained in non-striated structures, Z-disk proteins, such as alpha-actinin, were mainly found in primitive dot-like structures on actin stress fibres, M-band-associated proteins (myomesin, obscurin, Nbr1, p62 and MURF2) remained punctate. These results show that integration of the M-band region of titin is required for myosin filament assembly, M-band formation and maturation of the Z-disk. PMID:17038546

  18. AUTOPHAGY IN LOAD-INDUCED HEART DISEASE

    PubMed Central

    Zhu, Hongxin; Rothermel, Beverly A.; Hill, Joseph A.

    2009-01-01

    The heart is a highly plastic organ capable of remodeling in response to changes in physiological or pathological demand. When workload increases, the heart compensates through hypertrophic growth of individual cardiomyocytes to increase cardiac output. However, sustained stress, such as occurs with hypertension or following myocardial infarction, triggers changes in sarcomeric protein composition and energy metabolism, loss of cardiomyocytes, ventricular dilation, reduced pump function, and ultimately heart failure. It has been known for some time that autophagy is active in cardiomyocytes, occurring at increased levels in disease. Yet the potential contribution of cardiomyocyte autophagy to ventricular remodeling and disease pathogenesis has only recently been explored. This latter fact stems largely from the recent emergence of tools to probe molecular mechanisms governing cardiac plasticity and to define the role of autophagic flux in the context of heart disease. In this chapter, we briefly review prominent mouse models useful in the study of load-induced heart disease and standard techniques used to assess whether a molecular or cellular event is adaptive or maladaptive. We then outline methods available for monitoring autophagic activity in the heart, providing detailed protocols for several techniques unique to working with heart and other striated muscles. PMID:19216915

  19. How do keratinizing disorders and blistering disorders overlap?

    PubMed

    Hamada, Takahiro; Tsuruta, Daisuke; Fukuda, Shunpei; Ishii, Norito; Teye, Kwesi; Numata, Sanae; Dainichi, Teruki; Karashima, Tadashi; Ohata, Chika; Furumura, Minao; Hashimoto, Takashi

    2013-02-01

    Inherited keratinizing disorders are caused by mutations in the genes encoding cornified cell envelope proteins, enzymes and their inhibitors, adhesion molecules, cytoskeletal proteins and others in the epidermis. These molecules are known to regulate differentiation, proliferation and cell adhesions. Intriguingly, some keratinizing disorders show blistering skin lesions, while some inherited blistering disorders show abnormal keratinization. Therefore, hereditary keratinizing and blistering diseases are closely related and show overlapping genetic backgrounds. In this review, we overviewed keratinizing and blistering disorders in terms of overlapping of the two disease groups. Gene mutations in desmosomal components cause striate keratoderma, Naxos disease, epidermolytic palmoplantar keratoderma and plakophilin deficiency, which first show skin fragility and blisters and later hyperkeratosis. Gene mutations in hemidesmosomal components cause various forms of epidermolysis bullosa, some of which show hyperkeratosis on the nails, palms and soles, in addition to blister formation. Diseases with gene mutations in calcium pump proteins are Darier disease and Hailey-Hailey disease, which show clinicopathological overlaps and develop both keratinizing and blistering skin lesions. Finally, gene mutations in epidermal keratins cause epidermolysis bullosa simplex, epidermolytic ichthyosis, superficial epidermolytic ichthyosis, epidermolytic palmoplantar keratoderma and pachyonychia congenita/focal palmoplantar keratoderma, which show thickening of the palms and soles with underlying blister formation. In general, responsible proteins for diseases developing both keratinizing and blistering conditions are adhesion molecules, calcium pump proteins and keratins, but not connexins, cornified cell envelop proteins, enzymes or inhibitors. It is still unknown how particular keratinizing diseases develop blisters and vice versa. PMID:23039137

  20. Inflammatory myopathy with severe tongue atrophy in Pembroke Welsh Corgi dogs.

    PubMed

    Toyoda, Kaoru; Uchida, Kazuyuki; Matsuki, Naoaki; Sakai, Hideo; Kitagawa, Masato; Saito, Miyoko; Sasaki, Jun; Nakayama, Hiroyuki

    2010-11-01

    A disease characterized by tongue and facial muscle atrophy has been recognized sporadically among Pembroke Welsh Corgi (PWC) dogs in Japan. The present study describes the pathologic findings of this canine syndrome. Histopathologic examinations were performed in 2 dogs, including a case of muscular biopsy. Identification and characterization of autoantibodies were attempted by fluorescent antibody test (FAT) and Western blot (WB) by using sera from 7 PWC dogs with typical clinical features, 6 PWC dogs with other clinical signs, and 2 from other breeds with polymyositis. Clinically, the 7 affected PWC dogs exhibited dysphagia with severe tongue atrophy, facial muscular atrophy, and occasional walking difficulty. Histopathologic examinations of the 2 dogs with clinical symptoms revealed moderate to severe inflammatory lesions characterized by lymphohistiocytic infiltration and muscular atrophy in the tongue and/or femoral muscles. The tongue lesions were very severe and accompanied by diffuse fatty infiltration. There were no major lesions in the nervous tissues examined. By FAT, an autoantibody against the cross striation of skeletal muscle was detected in sera from 5 affected PWC dogs. By using WB analysis, the autoantibodies recognized a 42-kDa molecule in striated muscle but not in the nervous tissues. All of the findings indicated that the unique disease of PWC dogs might be generalized inflammatory myopathy, whereas the detailed etiology concerning the dominant involvement of tongue muscles and the role of the autoantibody in the canine disease remain to be clarified. PMID:21088170

  1. Mouse myofibers lacking the SMYD1 methyltransferase are susceptible to atrophy, internalization of nuclei and myofibrillar disarray

    PubMed Central

    Stewart, M. David; Lopez, Suhujey; Nagandla, Harika; Soibam, Benjamin; Benham, Ashley; Nguyen, Jasmine; Valenzuela, Nicolas; Wu, Harry J.; Burns, Alan R.; Rasmussen, Tara L.; Tucker, Haley O.; Schwartz, Robert J.

    2016-01-01

    ABSTRACT The Smyd1 gene encodes a lysine methyltransferase specifically expressed in striated muscle. Because Smyd1-null mouse embryos die from heart malformation prior to formation of skeletal muscle, we developed a Smyd1 conditional-knockout allele to determine the consequence of SMYD1 loss in mammalian skeletal muscle. Ablation of SMYD1 specifically in skeletal myocytes after myofiber differentiation using Myf6cre produced a non-degenerative myopathy. Mutant mice exhibited weakness, myofiber hypotrophy, prevalence of oxidative myofibers, reduction in triad numbers, regional myofibrillar disorganization/breakdown and a high percentage of myofibers with centralized nuclei. Notably, we found broad upregulation of muscle development genes in the absence of regenerating or degenerating myofibers. These data suggest that the afflicted fibers are in a continual state of repair in an attempt to restore damaged myofibrils. Disease severity was greater for males than females. Despite equivalent expression in all fiber types, loss of SMYD1 primarily affected fast-twitch muscle, illustrating fiber-type-specific functions for SMYD1. This work illustrates a crucial role for SMYD1 in skeletal muscle physiology and myofibril integrity. PMID:26935107

  2. Neural control of the female urethral and anal rhabdosphincters and pelvic floor muscles

    PubMed Central

    de Groat, William C.

    2010-01-01

    The urethral rhabdosphincter and pelvic floor muscles are important in maintenance of urinary continence and in preventing descent of pelvic organs [i.e., pelvic organ prolapse (POP)]. Despite its clinical importance and complexity, a comprehensive review of neural control of the rhabdosphincter and pelvic floor muscles is lacking. The present review places historical and recent basic science findings on neural control into the context of functional anatomy of the pelvic muscles and their coordination with visceral function and correlates basic science findings with clinical findings when possible. This review briefly describes the striated muscles of the pelvis and then provides details on the peripheral innervation and, in particular, the contributions of the pudendal and levator ani nerves to the function of the various pelvic muscles. The locations and unique phenotypic characteristics of rhabdosphincter motor neurons located in Onuf's nucleus, and levator ani motor neurons located diffusely in the sacral ventral horn, are provided along with the locations and phenotypes of primary afferent neurons that convey sensory information from these muscles. Spinal and supraspinal pathways mediating excitatory and inhibitory inputs to the motor neurons are described; the relative contributions of the nerves to urethral function and their involvement in POP and incontinence are discussed. Finally, a detailed summary of the neurochemical anatomy of Onuf's nucleus and the pharmacological control of the rhabdosphincter are provided. PMID:20484700

  3. Fine Structure of Body Wall Cuticle of Females of Eight Genera of Heteroderidae

    PubMed Central

    Cliff, G. M.; Baldwin, J. G.

    1985-01-01

    Body wall cuticle of adult females of eight genera within the Heteroderidae was examined by transmission electron microscopy for comparison with previously studied species within the family. Cuticle structure was used to test some current hypotheses of phylogeny of Heteroderidae and to evaluate intrageneric variability in cuticle layering. Verutus, Rhizonema, and Meloidodera possess striated cuticle surfaces and have the simplest layering, suggesting that striations have not necessarily arisen repeatedly in Heteroderidae through convergent or parallel evolution. Atalodera and Thecavermiculatus possess similar cuticles with derived characteristics, strengthening the hypothesis that the two genera are sister groups. Similarly, the cuticle of Cactodera resembles the specialized cuticle of Globodera and Punctodera in having a basal layer (D) and a surface layer infused with electron-dense substance. Heterodera betulae has a unique cuticle in which the thickest layer (C) is infiltrated with an electron-dense matrix. Little intrageneric difference was found between cuticles of two species of Meloidodera or between two species of Atalodera. However, Atalodera ucri has a basal layer (E) not found in other Heteroderidae. The most striking intrageneric variation in cuticle structure was observed between the thin three-layered cuticle of Sarisodera africana and the much thicker four-layered cuticle of Sarisodera hydrophila; results do not support monophyly of Sarisodera. PMID:19294096

  4. Transgenic expression and purification of myosin isoforms using the Drosophila melanogaster indirect flight muscle system

    PubMed Central

    Caldwell, James T.; Melkani, Girish C.; Huxford, Tom; Bernstein, Sanford I.

    2011-01-01

    Biophysical and structural studies on muscle myosin rely upon milligram quantities of extremely pure material. However, many biologically interesting myosin isoforms are expressed at levels that are too low for direct purification from primary tissues. Efforts aimed at recombinant expression of functional striated muscle myosin isoforms in bacterial or insect cell culture have largely met with failure, although high level expression in muscle cell culture has recently been achieved at significant expense. We report a novel method for the use of strains of the fruit fly Drosophila melanogaster genetically engineered to produce histidine-tagged recombinant muscle myosin isoforms. This method takes advantage of the single muscle myosin heavy chain gene within the Drosophila genome, the high level of expression of accessible myosin in the thoracic indirect flight muscles, the ability to knock out endogenous expression of myosin in this tissue and the relatively low cost of fruit fly colony production and maintenance. We illustrate this method by expressing and purifying a recombinant histidine-tagged variant of embryonic body wall skeletal muscle myosin II from an engineered fly strain. The recombinant protein shows the expected ATPase activity and is of sufficient purity and homogeneity for crystallization. This system may prove useful for the expression and isolation of mutant myosins associated with skeletal muscle diseases and cardiomyopathies for their biochemical and structural characterization. PMID:22178692

  5. Somatic genital reflexes in rats with a nod to humans: anatomy, physiology, and the role of the social neuropeptides

    PubMed Central

    Normandin, Joseph J.; Murphy, Anne Z.

    2011-01-01

    Somatic genital reflexes such as ejaculation and vaginocervical contractions are produced through the striated muscles associated with the genitalia. The coordination of these reflexes is surprisingly complex and involves a number of lumbosacral spinal and supraspinal systems. The rat model has proved to be an excellent source of information regarding these mechanisms, and many parallels to research in humans can be drawn. An understanding of the spinal systems involving the lumbosacral spinal cord, both efferent and afferent, has been generated through decades of research. Spinal and supraspinal mechanisms of descending excitation, through a spinal ejaculation generator in the lumbar spinal cord and thalamus, and descending inhibition, through the ventrolateral medulla, have been identified and characterized both anatomically and physiologically. In addition, delineation of the neural circuits whereby ascending genitosensory information regarding the regulation of somatic genital reflexes is relayed supraspinally has also been the topic of recent investigation. Lastly, the importance of the “social neuropeptides” oxytocin and vasopressin in the regulation of somatic genital reflexes, and associated sociosexual behaviors, is emerging. This work not only has implications for understanding how nervous systems generate sexual behavior, but also provides treatment targets for sexual dysfunction in people. PMID:21338605

  6. Effects of glycine and proline on the calcium activation properties of skinned muscle fibre segments from crayfish and rat.

    PubMed

    Powney, E L; West, J M; Stephenson, D G; Dooley, P C

    2003-01-01

    The effects of the polar amino acid glycine (20 mmol l(-1)) and the non-polar amino acid proline (20 mmol l(-1)) on Ca(2+)-activated contraction have been examined in four types of striated muscle fibres. Single fibres dissected from the claw muscle of a crustacean (long- and short-sarcomere) and the hindlimb muscles of the rat (slow-twitch from soleus and fast-twitch from extensor digitorum longus) were activated in matched solutions that either contained the amino acid ('test') or not ('control'). The steady-state force produced in these solutions was used to determine the relation between force production and pCa (-log10[Ca2+]). The results show that in the concentrations used, glycine and proline had only small effects on the maximum Ca(2+)-activated force, pCa corresponding to 10, 50 and 90% maximum force (pCa10, pCa50, pCa90, respectively) or on the slope of the force-pCa curves in the four different fibre types. The relative lack of effects of glycine and proline on contractile activation would confer a distinct physiological advantage to force production of muscle of Cherax, where the concentrations of glycine and proline vary considerably. Finally, the results show that glycine and proline may be useful to balance control solutions when the effects of other amino acids or zwitterions on contractile activation are examined. PMID:14677649

  7. Ultrastructural characteristics and small subunit ribosomal DNA sequence of Vairimorpha cheracis sp. nov., (Microspora: Burenellidae), a parasite of the Australian yabby, Cherax destructor (Decapoda: Parastacidae).

    PubMed

    Moodie, Elizabeth G; Le Jambre, Leo F; Katz, Margaret E

    2003-11-01

    This is the first record of a species of Vairimorpha infecting a crustacean host. Vairimorpha cheracis sp. nov. was found in a highland population of the Australian freshwater crayfish, Cherax destructor. The majority of spores and earlier developmental stages of V. cheracis sp. nov. were found within striated muscle cells of the thorax, abdomen, and appendages of the crayfish. Only octosporoblastic sporogony within sporophorous vesicles (SPVs) was observed. Diplokaryotic sporonts separated into two uninucleate daughter cells, each of which gave rise to four sporoblasts in a rosette-shaped plasmodium, so that eight uninucleate spores were produced within the persistent ovoid SPV. Ultrastructural features of stages in the octosporoblastic sequence were similar to those described for Vairimorpha necatrix, the type species. Mature spores were pyriform in shape and averaged 3.4x1.9 microm in dimensions. The anterior polaroplast was lamellar in structure, and the posterior polaroplast vesicular. The polar filament was coiled 10-12 times, lateral to the posterior vacuole. The small subunit ribosomal DNA (SSU rDNA) of V. cheracis sp. nov. was sequenced and compared with other microsporidia. V. cheracis sp. nov. showed over 97% sequence identity with Vairimorpha imperfecta and five species of Nosema, and only 86% sequence identity with V. necatrix. The need for a taxonomic revision of the Nosema/Vairimorpha group of species is discussed. PMID:14726242

  8. Light and scanning electron microscopic features of the tongue in cattle egret.

    PubMed

    Al-Ahmady Al-Zahaby, Sheren

    2016-07-01

    Adult individuals of both sexes were sacrificed by decapitation and their tongues were teared out in order to be investigated. Cattle egret's tongue is distinguished into the apex, body, and root regions. A shallow median sulcus is apparently noticed on the dorsal surface of the tongue's body only. Histologically, the tongue mucosa is covered with a thick parakeratinized epithelium. The dorsal epithelia of the apex and body are densely packed with exfoliated superficial cells. However, the dorsal surface showed microridges observed on the surface epithelial cells. In the body region, the gland's outlets are integrated in glandular patches on the top of keratinized folds at both sides of the median sulcus. The ventral surface of the tongue is devoid of any glandular outlets. The egret's tongue is supported by a paraglossum cartilage wrapped up with a fibrous perichondrium and striated muscle fibers. It extends ventrally as paraglossale apex then flattened in the body giving the corpus paraglossale which bifurcates caudally in the root giving paraglossalis caudalis. The tongue exhibits certain features that are unique as an adaptation to food intake, the type of food, lifestyles and bird's habitat with no any sex-specific differences. Microsc. Res. Tech. 79:595-603, 2016. © 2016 Wiley Periodicals, Inc. PMID:27095031

  9. Mesodermal origin of median fin mesenchyme and tail muscle in amphibian larvae.

    PubMed

    Taniguchi, Yuka; Kurth, Thomas; Medeiros, Daniel Meulemans; Tazaki, Akira; Ramm, Robert; Epperlein, Hans-Henning

    2015-01-01

    Mesenchyme is an embryonic precursor tissue that generates a range of structures in vertebrates including cartilage, bone, muscle, kidney, and the erythropoietic system. Mesenchyme originates from both mesoderm and the neural crest, an ectodermal cell population, via an epithelial to mesenchymal transition (EMT). Because ectodermal and mesodermal mesenchyme can form in close proximity and give rise to similar derivatives, the embryonic origin of many mesenchyme-derived tissues is still unclear. Recent work using genetic lineage tracing methods have upended classical ideas about the contributions of mesodermal mesenchyme and neural crest to particular structures. Using similar strategies in the Mexican axolotl (Ambystoma mexicanum), and the South African clawed toad (Xenopus laevis), we traced the origins of fin mesenchyme and tail muscle in amphibians. Here we present evidence that fin mesenchyme and striated tail muscle in both animals are derived solely from mesoderm and not from neural crest. In the context of recent work in zebrafish, our experiments suggest that trunk neural crest cells in the last common ancestor of tetrapods and ray-finned fish lacked the ability to form ectomesenchyme and its derivatives. PMID:26086331

  10. Potential microRNA biomarkers for acute ischemic stroke.

    PubMed

    Zeng, Ye; Liu, Jing-Xia; Yan, Zhi-Ping; Yao, Xing-Hong; Liu, Xiao-Heng

    2015-12-01

    Acute ischemic stroke is a significant cause of high morbidity and mortality in the aging population globally. However, current therapeutic strategies for acute ischemic stroke are limited. Atherosclerotic plaque is considered an independent risk factor for acute ischemic stroke. To identify biomarkers for carotid atheromatous plaque, bioinformatics analysis of the gene microarray data of plaque and intact tissue from individuals was performed. Differentially expressed genes (DEGs) were identified using the Multtest and Limma packages of R language, including 56 downregulated and 69 upregulated DEGs. Enriched microRNA (miRNA or miR) DEGs networks were generated using WebGestalt software and the STRING databases, and the miRNAs were validated using serum from acute ischemic stroke patients with reverse transcription quantitative PCR (RT‑qPCR). Four confirmed differentially expressed miRNAs (miR‑9, ‑22, ‑23 and ‑125) were associated with 28 upregulated DEGs, and 7 miRNAs (miR‑9, ‑30, ‑33, ‑124, ‑181, ‑218 and ‑330) were associated with 25 downregulated DEGs. Gene ontology (GO) function suggested that the confirmed miRNA‑targeted DEGs predominantly associated with signal transduction, the circulatory system, biological adhesion, striated muscle contraction, wound healing and the immune system. The confirmed miRNA‑targeted genes identified serve as potential therapeutic targets for acute ischemic stroke. PMID:26459744

  11. Mesodermal origin of median fin mesenchyme and tail muscle in amphibian larvae

    PubMed Central

    Taniguchi, Yuka; Kurth, Thomas; Medeiros, Daniel Meulemans; Tazaki, Akira; Ramm, Robert; Epperlein, Hans-Henning

    2015-01-01

    Mesenchyme is an embryonic precursor tissue that generates a range of structures in vertebrates including cartilage, bone, muscle, kidney, and the erythropoietic system. Mesenchyme originates from both mesoderm and the neural crest, an ectodermal cell population, via an epithelial to mesenchymal transition (EMT). Because ectodermal and mesodermal mesenchyme can form in close proximity and give rise to similar derivatives, the embryonic origin of many mesenchyme-derived tissues is still unclear. Recent work using genetic lineage tracing methods have upended classical ideas about the contributions of mesodermal mesenchyme and neural crest to particular structures. Using similar strategies in the Mexican axolotl (Ambystoma mexicanum), and the South African clawed toad (Xenopus laevis), we traced the origins of fin mesenchyme and tail muscle in amphibians. Here we present evidence that fin mesenchyme and striated tail muscle in both animals are derived solely from mesoderm and not from neural crest. In the context of recent work in zebrafish, our experiments suggest that trunk neural crest cells in the last common ancestor of tetrapods and ray-finned fish lacked the ability to form ectomesenchyme and its derivatives. PMID:26086331

  12. COMPARATIVE SPERM ULTRASTRUCTURE IN FIVE GENERA OF THE NUDIBRANCH FAMILY CHROMODORIDIDAE (GASTROPODA: OPISTHOBRANCHIA).

    PubMed

    Wilson, NERIDA G.; Healy, JOHN M.

    2002-05-01

    Sperm ultrastructure is examined in representatives of five genera of the nudibranch gastropod family Chromodorididae: (Chromodoris, Hypselodoris, Glossodoris, Risbecia and Pectenodoris) and the results compared with previous work on other gastropods, especially other nudibranchs. As chromodoridid phylogeny is still incompletely understood, this study partly focuses on the search for new and as yet untapped sources of informative characters. Like spermatozoa of most other heterobranch gastropods, those of the Chromodorididae are elongate, complex cells composed of an acrosomal complex (small, rounded acrosomal vesicle, and columnar acrosomal pedestal), a condensed nucleus, sub-nuclear ring, a highly modified mid-piece (axoneme + coarse fibres surrounded by a glycogen-containing, helically-coiled mitochondrial derivative) and terminally a glycogen piece (or homologue thereof). The finely striated acrosomal pedestal is a synapomorphy of all genera examined here, but interestingly also occurs in at least one dorid (Rostanga arbutus). Substantial and potentially taxonomically informative differences were also observed between genera in the morphology of the nucleus, the neck region of the mid-piece, and also the terminal glycogen piece. The subnuclear ring is shown for the first time to be a segmented, rather than a continuous structure; similarly, the annular complex is shown to consist of two structures, the annulus proper and the herein-termed annular accessory body. PMID:12011239

  13. Studies on the juveniles of a species of Anisakis (Nematoda: Anisakidae) from the orangespotted trevally, Carangoides bayad (Carangidae), from the Red Sea, Egypt.

    PubMed

    Abdou, Nahed El-Sayed; Dronen, Norman O

    2007-12-01

    One out of 45 (2.2%) Orange-spotted trevally, Carangoides bayad (Carangidae), collected off the coast of Egypt in the Red Sea was naturally infected with juveniles of a species of Anisakis (Anisakidae). Most of the juveniles were found free in the body cavity and unencapsulated on the surface of the liver. The morphology of juveniles was studied using both light microscopy and SEM. The anterior extremity of larvae had a circle of 4 papillae; the characteristic boring tooth, and lateral amphids arranged around a triangular mouth; a cylindrical, esophagus that is light colored with muscular and ven-tricular portions; colorless excretory canals; excretory pore situated just behind the boring tooth. The cuticular surface of the entire body except the cephalic region was striated with discontinuous, undulating longitudinal bands and transverse striations. The posterior extremity was rounded with a distinct mucron. The external morphological features of the juveniles were compared to the previous described genera and species in family Anisakidae harboring the Red Sea fishes. PMID:18383805

  14. Fear recognition in the voice is modulated by unconsciously recognized facial expressions but not by unconsciously recognized affective pictures

    PubMed Central

    de Gelder, Beatrice; Pourtois, Gilles; Weiskrantz, Lawrence

    2002-01-01

    Multisensory integration is a powerful mechanism for increasing adaptive responses, as illustrated by binding of fear expressed in a face with fear present in a voice. To understand the role of awareness in intersensory integration of affective information we studied multisensory integration under conditions of conscious and nonconscious processing of the visual component of an audiovisual stimulus pair. Auditory-event-related potentials were measured in two patients (GY and DB) who were unable to perceive visual stimuli consciously because of striate cortex damage. To explore the role of conscious vision of audiovisual pairing, we also compared audiovisual integration in either naturalistic pairings (a facial expression paired with an emotional voice) or semantic pairings (an emotional picture paired with the same voice). We studied the hypothesis that semantic pairings, unlike naturalistic pairings, might require mediation by intact visual cortex and possibly by feedback to primary cortex from higher cognitive processes. Our results indicate that presenting incongruent visual affective information together with the voice translates as an amplitude decrease of auditory-event-related potentials. This effect obtains for both naturalistic and semantic pairings in the intact field, but is restricted to the naturalistic pairings in the blind field. PMID:11904455

  15. Biomarkers of multiorgan injury in a preclinical model of exertional heat stroke.

    PubMed

    King, Michelle A; Leon, Lisa R; Mustico, Danielle L; Haines, Joel M; Clanton, Thomas L

    2015-05-15

    It is likely that the pathophysiology of exertional heat stroke (EHS) differs from passive heat stroke (PHS), but this has been difficult to verify experimentally. C57Bl/6 mice were instrumented with temperature transponders and underwent 3 wk of training using voluntary and forced running wheels. An EHS group was exposed to environmental temperatures (Tenv) of 37.5, 38.5, or 39.5°C at either 30, 50, or 90% relative humidities (RH) while exercising on a forced running wheel. Results were compared with sham-matched exercise controls (EXC) and naïve controls (NC). In EHS, mice exercised in heat until they reached limiting neurological symptoms (loss of consciousness). The symptom-limited maximum core temperatures achieved were between 42.1 and 42.5°C at 50% RH. All mice that were followed for 4 days survived. Additional groups were killed at 0.5, 3, 24, and 96 h, post-EHS or -EXC. Histopathology revealed extensive damage in all regions of the small intestine, liver, and kidney. Plasma creatine kinase, blood urea nitrogen, alanine transaminase, and intestinal fatty acid binding protein-2 were significantly elevated compared with matched EXC and NC, suggesting multiple organ injury to striated muscle, kidney, liver, and intestine, respectively. EHS mice were hypoglycemic immediately following EHS but exhibited sustained hyperglycemia through 4 days. The results demonstrate unique features of survivable EHS in the mouse that included loss of consciousness, extensive organ injury, and rhabdomyolysis. PMID:25814640

  16. A Single-Cell-Type Real-Time PCR Method Based on a Modified Patch-Pipette Cell Harvesting System.

    PubMed

    Song, Yuanlong; Zhang, Miaomiao; Tao, Xiaoqing; Xu, Zifen; Zhang, Liangpin; Zheng, Yunjie; Zhu, Minjie; Gao, Linlin

    2016-09-01

    Real-time PCR is a powerful tool for quantifying nucleic acid expression. Real-time PCR is conventionally performed at the tissue level to guarantee an abundance of nucleic acid for detection. The precision and reliability of this method, however, is limited by usually being composed of a mixture of different cell types. Single-cell PCR, in contrast, eliminates the purity problem of the cell source. However, use of this method is usually impeded by difficulties in cell harvesting and stringent requirements for processing of very small quantities of nucleic acids. In this study, we combined the advantages of the high purity of selected cells in single-cell PCR with the greater nucleic acid quantities and thus greater ease of tissue-level PCR. The key aspect of our method is to use a modified patch-clamp pipette to harvest several selected cells of the same type. This method is therefore especially useful for cells that can be morphologically or histologically identified such as primary sensory neurons, striated muscle fibers and cells labeled with fluorescent makers. PMID:27271017

  17. A new mechanokinetic model for muscle contraction, where force and movement are triggered by phosphate release.

    PubMed

    Smith, David A

    2014-12-01

    The atomic structure of myosin-S1 suggests that its working stroke, which generates tension and shortening in muscle, is triggered by the release of inorganic phosphate from the active site. This mechanism is the basis of a new mechanokinetic model for contractility, using the biochemical actomyosin ATPase cycle, strain-dependent kinetics and dimeric myosins on buckling rods. In this model, phosphate-dependent aspects of contractility arise from a rapid reversible release of phosphate from the initial bound state (A.M.ADP.Pi), which triggers the stroke. Added phosphate drives bound myosin towards this initial state, and the transient tension response to a phosphate jump reflects the rate at which it detaches from actin. Predictions for the tensile and energetic properties of striated muscle as a function of phosphate level, including the tension responses to length steps and Pi-jumps, are compared with experimental data from rabbit psoas fibres at 10 °C. The phosphate sensitivity of isometric tension is maximal when the actin affinity of M.ADP.Pi is near unity. Hence variations in actin affinity modulate the phosphate dependence of isometric tension, and may explain why phosphate sensitivity is temperature-dependent or absent in different muscles. PMID:25319769

  18. Derivation of a continuous myogenic cell culture from an embryo of common killifish, Fundulus heteroclitus.

    PubMed

    Gignac, Sarah J; Vo, Nguyen T K; Mikhaeil, Michael S; Alexander, J Andrew N; MacLatchy, Deborah L; Schulte, Patricia M; Lee, Lucy E J

    2014-09-01

    The common killifish or mummichog (Fundulus heteroclitus) is an estuarine teleost increasingly used in comparative physiology, toxicology and embryology. Their ability to withstand extreme environmental conditions and ease of maintenance has made them popular aquatic research organisms. Scientific advances with most popular model organisms have been assisted with the availability of continuous cell lines; however, cell lines from F. heteroclitus appear to be unavailable. The development of a killifish cell line, KFE-5, derived from the mid trunk region of a late stage embryo is described here. KFE-5 grows well in Leibovitz's L-15 media with 10% fetal bovine serum (FBS). This cell line has been passaged over 60 times in a span of three years, and cells at various passages have been successfully cryopreserved and thawed. The cells are mostly fibroblastic but contain myogenic cells that differentiate into mono-, bi- and multi-nucleated striated myocytes. Immunofluorescence detection of muscle specific antigens such as α-actinin, desmin, and myosin confirms KFE-5 as a myogenic cell line. KFE-5 has a temperature preference for 26-28°C and has been shown to withstand temperatures up to 37°C. The cell line responds to chemical signals including growth factors, hormones and extracellular matrix components. KFE-5 could thus be useful not only for mummichog's thermobiology but also for studies in fish muscle physiology and development. PMID:24836542

  19. Mechano-signaling in heart failure.

    PubMed

    Buyandelger, Byambajav; Mansfield, Catherine; Knöll, Ralph

    2014-06-01

    Mechanosensation and mechanotransduction are fundamental aspects of biology, but the link between physical stimuli and biological responses remains not well understood. The perception of mechanical stimuli, their conversion into biochemical signals, and the transmission of these signals are particularly important for dynamic organs such as the heart. Various concepts have been introduced to explain mechanosensation at the molecular level, including effects on signalosomes, tensegrity, or direct activation (or inactivation) of enzymes. Striated muscles, including cardiac myocytes, differ from other cells in that they contain sarcomeres which are essential for the generation of forces and which play additional roles in mechanosensation. The majority of cardiomyopathy causing candidate genes encode structural proteins among which titin probably is the most important one. Due to its elastic elements, titin is a length sensor and also plays a role as a tension sensor (i.e., stress sensation). The recent discovery of titin mutations being a major cause of dilated cardiomyopathy (DCM) also underpins the importance of mechanosensation and mechanotransduction in the pathogenesis of heart failure. Here, we focus on sarcomere-related mechanisms, discuss recent findings, and provide a link to cardiomyopathy and associated heart failure. PMID:24531746

  20. Intradermal Gene Immunization: The Possible Role of DNA Uptake in the Induction of Cellular Immunity to Viruses

    NASA Astrophysics Data System (ADS)

    Raz, Eyal; Carson, Dennis A.; Parker, Suezanne E.; Parr, Tyler B.; Abai, Anna M.; Aichinger, Gerald; Gromkowski, Stanislaw H.; Singh, Malini; Lew, Denise; Yankauckas, Michelle A.; Baird, Stephen M.; Rhodes, Gary H.

    1994-09-01

    The skin and mucous membranes are the anatomical sites where most viruses are first encountered by the immune system. Previous experiments have suggested that striated muscle cells are unique among mammalian cell types in their capacity to take up and express free DNA in the absence of a viral vector or physical carrier. However, we have found that mice injected into the superficial skin with free (naked) plasmid DNA encoding the influenza nucleoprotein gene had discrete foci of epidermal and dermal cells, including cells with dendritic morphology, that contained immunoreactive nucleoprotein antigen. A single intradermal administration of 0.3-15 μ g of free plasmid DNA induced anti-nucleoprotein-specific antibody and cytotoxic T lymphocytes that persisted for at least 68-70 weeks after vaccination. Intradermal gene administration induced higher antibody titers than did direct gene injection into skeletal muscle and did not cause local inflammation or necrosis. Compared with control animals, the gene-injected mice were resistant to challenge with a heterologous strain of influenza virus. These results indicate that the cells of the skin can take up and express free foreign DNA and induce cellular and humoral immune responses against the encoded protein. We suggest that DNA uptake by the skin-associated lymphoid tissues may play a role in the induction of cytotoxic T cells against viruses and other intracellular pathogens.

  1. Long-term insulin-like growth factor-I expression in skeletal muscles attenuates the enhanced in vitro proliferation ability of the resident satellite cells in transgenic mice

    NASA Technical Reports Server (NTRS)

    Chakravarthy, M. V.; Fiorotto, M. L.; Schwartz, R. J.; Booth, F. W.

    2001-01-01

    Insulin-like growth factor-I (IGF-I) overexpression for 1-month in mouse skeletal muscle increases satellite cell proliferation potential. However, it is unknown whether this beneficial enhancement by IGF-I expression would persist over a longer-term duration in aged mice. This is an important issue to address if a prolonged course of IGF-I is to be used clinically in muscle-wasting conditions where satellite cells may become limiting. Using the IGF-I transgenic (IGF-I Tg) mouse that selectively expresses the IGF-I transgene in striated muscles, we found that 18-months of continuous IGF-I overexpression led to a loss in the enhanced in vitro proliferative capacity of satellite cells from Tg skeletal muscles. Also 18-month-old IGF-I Tg satellite cells lost the enhanced BrdU incorporation, greater pRb and Akt phosphorylations, and decreased p27(Kip1) levels initially observed in cells from 1-month-old IGF-I Tg mice. The levels of those biochemical markers reverted to similar values seen in the 18-months WT littermates. These findings, therefore, suggest that there is no further beneficial effect on enhancing satellite cell proliferation ability with persistent long-term expression of IGF-I in skeletal muscles of these transgenic mice.

  2. In silico prediction of long intergenic non-coding RNAs in sheep.

    PubMed

    Bakhtiarizadeh, Mohammad Reza; Hosseinpour, Batool; Arefnezhad, Babak; Shamabadi, Narges; Salami, Seyed Alireza

    2016-04-01

    Long non-coding RNAs (lncRNAs) are transcribed RNA molecules >200 nucleotides in length that do not encode proteins and serve as key regulators of diverse biological processes. Recently, thousands of long intergenic non-coding RNAs (lincRNAs), a type of lncRNAs, have been identified in mammalians using massive parallel large sequencing technologies. The availability of the genome sequence of sheep (Ovis aries) has allowed us genomic prediction of non-coding RNAs. This is the first study to identify lincRNAs using RNA-seq data of eight different tissues of sheep, including brain, heart, kidney, liver, lung, ovary, skin, and white adipose. A computational pipeline was employed to characterize 325 putative lincRNAs with high confidence from eight important tissues of sheep using different criteria such as GC content, exon number, gene length, co-expression analysis, stability, and tissue-specific scores. Sixty-four putative lincRNAs displayed tissues-specific expression. The highest number of tissues-specific lincRNAs was found in skin and brain. All novel lincRNAs that aligned to the human and mouse lincRNAs had conserved synteny. These closest protein-coding genes were enriched in 11 significant GO terms such as limb development, appendage development, striated muscle tissue development, and multicellular organismal development. The findings reported here have important implications for the study of sheep genome. PMID:27002388

  3. Improved mapping of information distribution across the cortical surface with the Support Vector Machine

    PubMed Central

    Xiao, Youping; Rao, Ravi; Cecchi, Guillermo; Kaplan, Ehud

    2008-01-01

    The early visual cortices represent information of several stimulus attributes, such as orientation and color. To understand the coding mechanisms of these attributes in the brain, and the functional organization of the early visual cortices, it is necessary to determine whether different attributes are represented by different compartments within each cortex. Previous studies addressing this question have focused on the information encoded by the response amplitude of individual neurons or cortical columns, and have reached conflicting conclusions. Given the correlated variability in response amplitude across neighboring columns, it is likely that the spatial pattern of responses across these columns encodes the attribute information more reliably than the response amplitude does. Here we present a new method of mapping the spatial distribution of information that is encoded by both the response amplitude and spatial pattern. This new method is based on a statistical learning approach, the Support Vector Machine (SVM). Application of this new method to our optical imaging data suggests that information about stimulus orientation and color are distributed differently in the striate cortex, and this observation is consistent with the hypothesis of segregated representations of orientation and color in this area. We also demonstrate that SVM can be used to extract ‘single-condition’ activation maps from noisy images of intrinsic optical signals. PMID:18249089

  4. Assignment of the human fast skeletal troponin T gene (TNNT3) to chromosome 11p15.5: Evidence for the presence of 11pter in a monochromosome 9 somatic cell hybrid in NIGMS mapping panel 2

    SciTech Connect

    Mao, Chengjian; Jha, P.K.; Sarkar, S.

    1996-02-01

    Human fast skeletal troponin T (TnT{sub f}), the tropomyosin binding component of the multisubunit troponin complex, plays an important role in the Ca{sup 2+} regulation of striated muscle contraction. Specific primers designed from the 3{prime} end of human TnT{sub f} cDNA were used to amplify an intronic region by polymerase chain reaction (PCR). This TnT{sub f}-specific PCR product was detected from two somatic cell hybrids containing human chromosomes 9 and 11, respectively, in NIGMS mapping panel 2. However, further studies with other somatic hybrid cell lines (Bios Laboratory) localized the TnT{sub f} genomic probe generated by extended PCR, showing the sublocalization of the gene to band p15.5 on chromosome 11. This locus is of specific interest, as Beckwith-Wiedemann syndrome and various childhood and adult tumor-related abnormalities have been mapped to this region. The study also indicates the presence of an 11pter region in the NIGMS cell hybrid GM10611, which has previously been reported to contain only human chromosome 9. 11 refs., 2 figs.

  5. Atypical visual processing in posttraumatic stress disorder☆

    PubMed Central

    Mueller-Pfeiffer, Christoph; Schick, Matthis; Schulte-Vels, Thomas; O'Gorman, Ruth; Michels, Lars; Martin-Soelch, Chantal; Blair, James R.; Rufer, Michael; Schnyder, Ulrich; Zeffiro, Thomas; Hasler, Gregor

    2013-01-01

    Background Many patients with Posttraumatic Stress Disorder (PTSD) feel overwhelmed in situations with high levels of sensory input, as in crowded situations with complex sensory characteristics. These difficulties might be related to subtle sensory processing deficits similar to those that have been found for sounds in electrophysiological studies. Method Visual processing was investigated with functional magnetic resonance imaging in trauma-exposed participants with (N = 18) and without PTSD (N = 21) employing a picture-viewing task. Results Activity observed in response to visual scenes was lower in PTSD participants 1) in the ventral stream of the visual system, including striate and extrastriate, inferior temporal, and entorhinal cortices, and 2) in dorsal and ventral attention systems (P < 0.05, FWE-corrected). These effects could not be explained by the emotional salience of the pictures. Conclusions Visual processing was substantially altered in PTSD in the ventral visual stream, a component of the visual system thought to be responsible for object property processing. Together with previous reports of subtle auditory deficits in PTSD, these findings provide strong support for potentially important sensory processing deficits, whose origins may be related to dysfunctional attention processes. PMID:24371791

  6. The incidence of bifurcation among corticocortical connections from area 17 in the developing visual cortex of the cat.

    PubMed

    Price, D J; Ferrer, J M

    1993-03-01

    In newborn kittens, cells in the striate cortex (visual area 17) that project to area 18 (part of extrastriate cortex) are distributed with uniform density in the superficial and in the deep layers. During postnatal weeks 2-3, some of these corticocortical connections are removed to generate an adult-like projection in which association cells are clustered mainly in the superficial layers of area 17. Axonal elimination, without cell death, is the major factor sculpting patches of corticocortical cells in superficial layers. In adult cats, few cells in area 17 (approximately 5%) have axons that bifurcate to multiple extrastriate areas. We have studied the possibility that the early exuberant innervation of area 18 by neurons in area 17 is largely from the transient collaterals of axons that also project to other visual areas. Kittens aged 2-21 days were each injected with a pair of retrogradely transported tracers, either diamidino yellow and fast blue, or diamidino yellow and a carbocyanine dye, at retinotopically corresponding points in area 18 and either area 19 or the posteromedial lateral suprasylvian cortex (PMLS). As for injections in area 18, those in area 19 and PMLS in kittens aged < or = 5 days labelled cells in continuous bands in area 17; in older kittens neurons projecting from area 17 to extrastriate regions were in patches, mainly in superficial layers. In each animal, the labelling from the two injections overlapped by 51-92%.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8261103

  7. Induction of mesenchymal stem cell differentiation and cartilage formation by cross-linker-free collagen microspheres.

    PubMed

    Mathieu, M; Vigier, S; Labour, M N; Jorgensen, C; Belamie, E; Noël, D

    2014-01-01

    Because of poor self-healing ability, joint cartilage can undergo irreversible degradation in the course of various diseases or after injury. A promising approach for cartilage engineering consists of using of mesenchymal stem cells (MSC) and a differentiation factor combined with an injectable carrier biomaterial. We describe here a novel synthesis route for native collagen microspheres that does not involve the use of potentially toxic crosslinking agents. An emulsion was formed between a type I collagen solution and perfluorinated oil, stabilised by a biocompatible triblock perfluorinated copolymer surfactant. Spherical microparticles of fibrillar collagen were formed through a sol-gel transition induced by ammonia vapours. Electron microscopy observations showed that these self-cross-linked microspheres were constituted by a gel of striated collagen fibrils. Microspheres that were loaded with transforming growth factor beta (TGF-β)3 progressively released this differentiation factor over a four weeks period. Human MSC rapidly adhered to TGF-β3-loaded microspheres and, after 21 d of culture, exhibited typical chondrocyte morphology and produced an uncalcified matrix made of the predominant cartilage components, aggrecan and type II collagen, but devoid of the hypertrophic marker type X collagen. Subcutaneous co-injection of MSC and TGF-β3-loaded microspheres in mice consistently led to the formation of a cartilage-like tissue, which was however hypertrophic, calcified and vascularised. In conclusion, we developed cross-linker free collagen microspheres that allowed chondrogenic differentiation of MSC in vitro and in vivo. PMID:25179212

  8. A Comprehensive Review on Methodologies Employed for Visual Evoked Potentials

    PubMed Central

    Kothari, Ruchi; Bokariya, Pradeep; Singh, Smita; Singh, Ramji

    2016-01-01

    Visual information is fundamental to how we appreciate our environment and interact with others. The visual evoked potential (VEP) is among those evoked potentials that are the bioelectric signals generated in the striate and extrastriate cortex when the retina is stimulated with light which can be recorded from the scalp electrodes. In the current paper, we provide an overview of the various modalities, techniques, and methodologies which have been employed for visual evoked potentials over the years. In the first part of the paper, we cast a cursory glance on the historical aspect of evoked potentials. Then the growing clinical significance and advantages of VEPs in clinical disorders have been briefly described, followed by the discussion on the earlier and currently available methods for VEPs based on the studies in the past and recent times. Next, we mention the standards and protocols laid down by the authorized agencies. We then summarize the recently developed techniques for VEP. In the concluding section, we lay down prospective research directives related to fundamental and applied aspects of VEPs as well as offering perspectives for further research to stimulate inquiry into the role of visual evoked potentials in visual processing impairment related disorders. PMID:27034907

  9. Interactions with M-band Titin and Calpain 3 Link Myospryn (CMYA5) to Tibial and Limb-girdle Muscular Dystrophies*

    PubMed Central

    Sarparanta, Jaakko; Blandin, Gaëlle; Charton, Karine; Vihola, Anna; Marchand, Sylvie; Milic, Astrid; Hackman, Peter; Ehler, Elisabeth; Richard, Isabelle; Udd, Bjarne

    2010-01-01

    Mutations in the C terminus of titin, situated at the M-band of the striated muscle sarcomere, cause tibial muscular dystrophy (TMD) and limb-girdle muscular dystrophy (LGMD) type 2J. Mutations in the protease calpain 3 (CAPN3), in turn, lead to LGMD2A, and secondary CAPN3 deficiency in LGMD2J suggests that the pathomechanisms of the diseases are linked. Yeast two-hybrid screens carried out to elucidate the molecular pathways of TMD/LGMD2J and LGMD2A resulted in the identification of myospryn (CMYA5, cardiomyopathy-associated 5) as a binding partner for both M-band titin and CAPN3. Additional yeast two-hybrid and coimmunoprecipitation studies confirmed both interactions. The interaction of myospryn and M-band titin was supported by localization of endogenous and transfected myospryn at the M-band level. Coexpression studies showed that myospryn is a proteolytic substrate for CAPN3 and suggested that myospryn may protect CAPN3 from autolysis. Myospryn is a muscle-specific protein of the tripartite motif superfamily, reported to function in vesicular trafficking and protein kinase A signaling and implicated in the pathogenesis of Duchenne muscular dystrophy. The novel interactions indicate a role for myospryn in the sarcomeric M-band and may be relevant for the molecular pathomechanisms of TMD/LGMD2J and LGMD2A. PMID:20634290

  10. Krp1 (Sarcosin) promotes lateral fusion of myofibril assembly intermediates in cultured mouse cardiomyocytes

    SciTech Connect

    Greenberg, Cynthia C.; Connelly, Patricia S.; Daniels, Mathew P.; Horowits, Robert

    2008-03-10

    Krp1, also called sarcosin, is a cardiac and skeletal muscle kelch repeat protein hypothesized to promote the assembly of myofibrils, the contractile organelles of striated muscles, through interaction with N-RAP and actin. To elucidate its role, endogenous Krp1 was studied in primary embryonic mouse cardiomyocytes. While immunofluorescence showed punctate Krp1 distribution throughout the cell, detergent extraction revealed a significant pool of Krp1 associated with cytoskeletal elements. Reduction of Krp1 expression with siRNA resulted in specific inhibition of myofibril accumulation with no effect on cell spreading. Immunostaining analysis and electron microscopy revealed that cardiomyocytes lacking Krp1 contained sarcomeric proteins with longitudinal periodicities similar to mature myofibrils, but fibrils remained thin and separated. These thin myofibrils were degraded by a scission mechanism distinct from the myofibril disassembly pathway observed during cell division in the developing heart. The data are consistent with a model in which Krp1 promotes lateral fusion of adjacent thin fibrils into mature, wide myofibrils and contribute insight into mechanisms of myofibrillogenesis and disassembly.

  11. Spermiogenesis and spermatozoon ultrastructure of the cranial digenean Troglotrema acutum (Leuckart, 1842).

    PubMed

    Miquel, Jordi; Fournier-Chambrillon, Christine; Fournier, Pascal; Torres, Jordi

    2006-06-01

    Ultrastructure of spermiogenesis and the main characters of the mature spermatozoon of Troglotrema acutum are described by means of transmission electron microscopy. Specimens were obtained from the nasolacrimal sinuses of an American mink (Mustela vison). Spermiogenesis in T. acutum follows the general pattern of digeneans. The zone of differentiation is a conical-shaped area bordered by cortical microtubules and delimited at its base by a ring of arched membranes. This area contains 2 centrioles associated with striated rootlets and an intercentriolar body between them. The centrioles develop 2 free flagella that grow ortogonally to the median cytoplasmic process. The posterior flagellar rotation and proximodistal fusion of the free flagella with the median cytoplasmic process originate the spermatozoon. The mature spermatozoon of T. acutum is characterized by the presence of 2 axonemes of different lengths presenting the 9+'1' trepaxonematan pattern, 2 bundles of parallel cortical microtubules, 2 mitochondria, a nucleus, and granules of glycogen. These ultrastructural characters are compared with other digenean species previously studied and the importance of different spermatological features is discussed. PMID:16883984

  12. Management of detrusor external sphincter dyssynergia in neurogenic bladder.

    PubMed

    Mahfouz, W; Corcos, J

    2011-12-01

    Spinal cord injury (SCI) affects 11.5 to 53.4 individuals per million of the population in developed countries each year. SCI is caused by trauma, although it can also result from myelopathy, myelitis, vascular disease or arteriovenous malformations and multiple sclerosis. Patients with complete lesions of the spinal cord between spinal cord level T6 and S2, after they recover from spinal shock, generally exhibit involuntary bladder contractions without sensation, smooth sphincter synergy, but with detrusor striated sphincter dyssynergia (DESD). Those with lesions above spinal cord level T6 may experience, in addition, smooth sphincter dyssynergia and autonomic hyperreflexia. DESD is a debilitating problem in patients with SCI. It carries a high risk of complications, and even life expectancy can be affected. Nearly half of the patients with untreated DESD will develop deleterious urologic complications, due to high intravesical pressures, resulting in urolithiasis, urinary tract infection (UTI), vesicoureteral reflux (VUR), hydronephrosis, obstructive uropathy, and renal failure. The mainstay of treatment is the use of antimuscarinics and catheterization, but in those for whom this is not possible external sphincterotomy has been a last resort option. External sphincterotomy is associated with significant risks, including haemorrhage; erectile dysfunction and the possibility of redo procedures. Over the last decade alternatives have been investigated, such as urethral stents and intrasphincteric botulinum toxin injection. In this review, we will cover neurogenic DESD, with emphasis on definition, classifications, diagnosis and different therapeutic options available. PMID:22081065

  13. Overlapping multivoxel patterns for two levels of visual expectation

    PubMed Central

    de Gardelle, Vincent; Stokes, Mark; Johnen, Vanessa M.; Wyart, Valentin; Summerfield, Christopher

    2013-01-01

    According to predictive accounts of perception, visual cortical regions encode sensory expectations about the external world, and the violation of those expectations by inputs (surprise). Here, using multi-voxel pattern analysis (MVPA) of functional magnetic resonance imaging (fMRI) data, we asked whether expectations and surprise activate the same pattern of voxels, in face-sensitive regions of the extra-striate visual cortex (the fusiform face area or FFA). Participants viewed pairs of repeating or alternating faces, with high or low probability of repetitions. As in previous studies, we found that repetition suppression (the attenuated BOLD response to repeated stimuli) in the FFA was more pronounced for probable repetitions, consistent with it reflecting reduced surprise to anticipated inputs. Secondly, we observed that repetition suppression and repetition enhancement responses were both consistent across scanner runs, suggesting that both have functional significance, with repetition enhancement possibly indicating the build up of sensory expectation. Critically, we also report that multi-voxels patterns associated with probability and repetition effects were significantly correlated within the left FFA. We argue that repetition enhancement responses and repetition probability effects can be seen as two types of expectation signals, occurring simultaneously, although at different processing levels (lower vs. higher), and different time scales (immediate vs. long term). PMID:23630488

  14. The role of collagen in bone apatite formation in the presence of hydroxyapatite nucleation inhibitors

    PubMed Central

    Nudelman, Fabio; Pieterse, Koen; George, Anne; Bomans, Paul H. H.; Friedrich, Heiner; Brylka, Laura J.; Hilbers, Peter A. J.; de With, Gijsbertus; Sommerdijk, Nico A. J. M.

    2011-01-01

    Bone is a composite material, in which collagen fibrils form a scaffold for a highly organized arrangement of uniaxially oriented apatite crystals1,2. In the periodic 67 nm cross-striated pattern of the collagen fibril3–5, the less dense 40-nm-long gap zone has been implicated as the place where apatite crystals nucleate from an amorphous phase, and subsequently grow6–9. This process is believed to be directed by highly acidic non-collagenous proteins6,7,9–11; however, the role of the collagen matrix12–14 during bone apatite mineralization remains unknown. Here, combining nanometre-scale resolution cryogenic transmission electron microscopy and cryogenic electron tomography15 with molecular modelling, we show that collagen functions in synergy with inhibitors of hydroxyapatite nucleation to actively control mineralization. The positive net charge close to the C-terminal end of the collagen molecules promotes the infiltration of the fibrils with amorphous calcium phosphate (ACP). Furthermore, the clusters of charged amino acids, both in gap and overlap regions, form nucleation sites controlling the conversion of ACP into a parallel array of oriented apatite crystals. We developed a model describing the mechanisms through which the structure, supramolecular assembly and charge distribution of collagen can control mineralization in the presence of inhibitors of hydroxyapatite nucleation. PMID:20972429

  15. Electron Microscopic Observations on the Structure of Treponema zuelzerae and Its Axial Filaments

    PubMed Central

    Bharier, M. A.; Eiserling, F. A.; Rittenberg, S. C.

    1971-01-01

    The fine structure of the spirochete Treponema zuelzerae, and particularly of its axial filaments, was investigated by using the electron microscope. The cell consists of a protoplasmic core surrounded by two concentric envelopes, each approximately 12 nm in width. Between these envelopes are two axial filaments, one originating at each pole of the cell, which overlap and lie side by side in the central region of the cell. The diameter of the axial filaments is 18.0 to 18.5 nm. The terminal region of each filament at its proximal end consists of a hook-like structure, very similar in appearance to the proximal end of a bacterial flagellum. The outer envelope of the cell is readily disrupted with distilled water, and this treatment often results in the release of the filaments from their axial position. A sheath is seen surrounding the filaments when cells are treated with distilled water for no more than 1 min and fixed immediately with osmium tetroxide or glutaraldehyde. This sheath has a striated fine structure and a diameter of 46 nm. Images PMID:5541022

  16. Altered retinal cell differentiation in the AP-3 delta mutant (Mocha) mouse.

    PubMed

    Baguma-Nibasheka, Mark; Kablar, Boris

    2009-11-01

    Adaptor-related protein complex 3 delta 1 (Ap3d1) encodes the delta 1 subunit of an adaptor protein regulating intracellular vesicle-mediated transport, and the Ap3d-deletion mutant (Mocha) mouse undergoes rapid photoreceptor degeneration leading to blindness soon after birth. Previous microarray analysis revealed Ap3d down-regulation in the retina of mouse embryos specifically lacking cholinergic amacrine cells as a result of the absence of skeletal musculature. To investigate the role of Ap3d in the determination of retinal cell fate, the present study examined retinal morphology in newborn Ap3d-/- mice. The Ap3d-/- retina showed a complete absence of cholinergic amacrine cells and a decrease in parvalbumin-expressing amacrine cells and syntaxin- and VC1.1-expressing amacrine precursor cells, but had a normal number of cell layers and number of cells in each layer with no detectable difference in cell proliferation or apoptosis. These findings indicate that, despite having no apparent effect on the basic spatial organization of the retina at this stage of development, Ap3d could be involved in the regulation of progenitor cell competence and the eventual ratio of resulting differentiated cells. Finding the mouse mutant which phenocopies the eye defect seen in fetuses with no striated muscle was accomplished by the Systematic Subtractive Microarray Analysis Approach (SSMAA), explained in the discussion section. PMID:19631730

  17. The role of deformation bands, stylolites and sheared stylolites in fault development in carbonate grainstones of Majella Mountain, Italy

    NASA Astrophysics Data System (ADS)

    Tondi, Emanuele; Antonellini, Marco; Aydin, Atilla; Marchegiani, Leonardo; Cello, Giuseppe

    2006-03-01

    In this paper we document deformation processes in porous carbonate grainstones of Cretaceous age in Majella Mountain in the central Apennines of Italy by detailed mapping of meso- and microstructural features as well as thin section observations and image analyses. We distinguished three main deformation mechanisms: (i) deformation bands developed by compaction and shear strain localization, (ii) stylolites formed by pressure solution, and (iii) subsequent shearing of stylolites. The deformation bands occur in six sets: five sets are compactive shear bands at high angles to bedding and one, which is the oldest, occurs parallel to bedding and is interpreted to be a compaction band. Stylolites localize along and within all six sets of deformation bands and are commonly sheared, as evidenced by striated surfaces and detectable offsets. These sheared stylolites are in many cases associated with one or two sets of subsidiary stylolites, oblique to the major set. The band-parallel sheared stylolites, together with the associated oblique sets of stylolites, form a tabular zone of fine grained cataclastic material within the compactive shear bands and accommodate slip in the range of 5-75 cm. The bed-parallel compaction bands and bed-parallel stylolites, which are kinematically compatible, are interpreted to be pre-tilting structures developed in response to the overburden, whereas the five sets of compactive shear bands and the associated stylolites and sheared stylolites likely occurred during the syn- and post-tilting deformation phases recorded in the Majella anticline.

  18. A Simple Protocol for the Myocardial Differentiation of Human iPS Cells.

    PubMed

    Aikawa, Nobuo; Suzuki, Yui; Takaba, Katsumi

    2015-01-01

    We have developed a simple protocol for inducing the myocardial differentiation of human induced pluripotent stem (iPS) cells. Human iPS cell-derived embryonic bodies (EBs) were treated with a combination of activin-A, bone morphogenetic protein-4 and wnt-3a for one day in serum-free suspension culture, and were subsequently treated with noggin for three days. Thereafter, the EBs were subjected to adherent culture in media with 5% serum. All EBs were differentiated into spontaneously beating EBs, which were identified by the presence of striated muscles in transmission electron microscopy and the expression of the specific cardiomyocyte markers, NKX2-5 and TNNT2. The beating rate of the beating EBs was decreased by treatment with a rapidly activating delayed rectifier potassium current (Ikr) channel blocker, E-4031, an Ikr trafficking inhibitor, pentamidin, and a slowly activating delayed rectifier potassium current (Iks) channel blocker, chromanol 293B, and was increased by treatment with a beta-receptor agonist, isoproterenol. At a low concentration, verapamil, a calcium channel blocker, increased the beating rate of the beating EBs, while a high concentration decreased this rate. These findings suggest that the spontaneously beating EBs were myocardial cell clusters. This simple protocol for myocardial differentiation would be useful in providing a sufficient number of the beating myocardial cell clusters for studies requiring human myocardium. PMID:26133717

  19. Differences in the Expression and Distribution of Flotillin-2 in Chick, Mice and Human Muscle Cells

    PubMed Central

    Possidonio, Ana Claudia Batista; Soares, Carolina Pontes; Portilho, Débora Morueco; Midlej, Victor; Benchimol, Marlene; Butler-Browne, Gillian; Costa, Manoel Luis; Mermelstein, Claudia

    2014-01-01

    Myoblasts undergo a series of changes in the composition and dynamics of their plasma membranes during the initial steps of skeletal muscle differentiation. These changes are crucial requirements for myoblast fusion and allow the formation of striated muscle fibers. Membrane microdomains, or lipid rafts, have been implicated in myoblast fusion. Flotillins are scaffold proteins that are essential for the formation and dynamics of lipid rafts. Flotillins have been widely studied over the last few years, but still little is known about their role during skeletal muscle differentiation. In the present study, we analyzed the expression and distribution of flotillin-2 in chick, mice and human muscle cells grown in vitro. Primary cultures of chick myogenic cells showed a decrease in the expression of flotillin-2 during the first 72 hours of muscle differentiation. Interestingly, flotillin-2 was found to be highly expressed in chick myogenic fibroblasts and weakly expressed in chick myoblasts and multinucleated myotubes. Flotillin-2 was distributed in vesicle-like structures within the cytoplasm of chick myogenic fibroblasts, in the mouse C2C12 myogenic cell line, and in neonatal human muscle cells. Cryo-immunogold labeling revealed the presence of flotillin-2 in vesicles and in Golgi stacks in chick myogenic fibroblasts. Further, brefeldin A induced a major reduction in the number of flotillin-2 containing vesicles which correlates to a decrease in myoblast fusion. These results suggest the involvement of flotillin-2 during the initial steps of skeletal myogenesis. PMID:25105415

  20. Dissociation of the dystroglycan complex in caveolin-3-deficient limb girdle muscular dystrophy.

    PubMed

    Herrmann, R; Straub, V; Blank, M; Kutzick, C; Franke, N; Jacob, E N; Lenard, H G; Kröger, S; Voit, T

    2000-09-22

    Limb girdle muscular dystrophy is a group of clinically and genetically heterogeneous disorders inherited in an autosomal recessive or dominant mode. Caveolin-3, the muscle-specific member of the caveolin gene family, is implicated in the pathogenesis of autosomal dominant limb girdle muscular dystrophy 1C. Here we report on a 4-year-old girl presenting with myalgia and muscle cramps due to a caveolin-3 deficiency in her dystrophic skeletal muscle as a result of a heterozygous 136G-->A substitution in the caveolin-3 gene. The novel sporadic missense mutation in the caveolin signature sequence of the caveolin-3 gene changes an alanine to a threonine (A46T) and prevents the localization of caveolin-3 to the plasma membrane in a dominant negative fashion. Caveolin-3 has been suggested to interact with the dystrophin-glycoprotein complex, which in striated muscle fibers links the cytoskeleton to the extracellular matrix and with neuronal nitric oxide synthase. Similar to dystrophin-deficient Duchenne muscular dystrophy, a secondary decrease in neuronal nitric oxide synthase and alpha-dystroglycan expression was detected in the caveolin-3-deficient patient. These results implicate an important function of the caveolin signature sequence and common mechanisms in the pathogenesis of dystrophin-glycoprotein complex-associated muscular dystrophies with caveolin-3-deficient limb girdle muscular dystrophy. PMID:11001938