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Sample records for oribicularis oris muscle

  1. Application of ultrasound imaging of upper lip orbicularis oris muscle.

    PubMed

    Zhang, Wen-Hao; Chen, Yuan-Yuan; Liu, Jun-Jie; Liao, Xin-Hong; Du, Yang-Chun; Gao, Yong

    2015-01-01

    In this study, we aim to understand the morphology and structure of upper lip orbicularis oris muscle, and to provide clinical evidence for evaluating the effect of repair operation in cleft lip. Subjects included 106 healthy people and 36 postoperative patients of unilateral cleft lip. The upper lip orbicularis oris muscle was scanned using ultrasound in natural closure and pout states. Our results showed that the hierarchical structure of upper lip tissue was demonstrated clearly in ultrasonic images. After reconstruction of unilateral cleft lip, the left and right philtrum columns were still obviously asymmetric, their radian displayed clearly and showed better continuity. In the place of cleft lip side equivalent to philtrum columns, orbicularis oris muscle showed discontinuity and unclear hierarchical structure, which was replaced by hyperechoic scar tissue. The superficial layer would become thicker when pouting. In reconstructed unilateral cleft lip, the superficial layer was thinner than that of healthy controls. In normal upper lip orbicularis oris muscle, the superficial layer thickness was no less than 2.89 mm in philtrum dimple and no less than 3.92 mm in philtrum column, and the deep layer thickness was no less the 1.12 mm. Otherwise, the layer thickness less than above reference values may be considered as diagnostic criteria for dysplasia of upper lip orbicularis oris muscle. In conclusions, ultrasound imaging is able to clearly show the hierarchical structure of upper lip orbicularis oris muscle, and will be beneficial in guiding the upper lip repair and reconstruction surgery.

  2. Study on distribution of terminal branches of the facial nerve in mimetic muscles (orbicularis oculi muscle and orbicularis oris muscle).

    PubMed

    Mitsukawa, Nobuyuki; Moriyama, Hiroshi; Shiozawa, Kei; Satoh, Kaneshige

    2014-01-01

    There have been many anatomical reports to date regarding the course of the facial nerve to the mimetic muscles. However, reports are relatively scarce on the detailed distribution of the terminal branches of the facial nerve to the mimetic muscles. In this study, we performed detailed examination of the terminal facial nerve branches to the mimetic muscles, particularly the branches terminating in the orbicularis oculi muscle and orbicularis oris muscle. Examination was performed on 25 Japanese adult autopsy cases, involving 25 hemifaces. The mean age was 87.4 years (range, 60-102 years). There were 12 men and 13 women (12 left hemifaces and 13 right hemifaces). In each case, the facial nerve was exposed through a preauricular skin incision. The main trunk of the facial nerve was dissected from the stylomastoid foramen. A microscope was used to dissect the terminal branches to the periphery and observe them. The course and distribution were examined for all terminal branches of the facial nerve. However, focus was placed on the course and distribution of the zygomatic branch, buccal branch, and mandibular branch to the orbicularis oculi muscle and orbicularis oris muscle. The temporal branch was distributed to the orbicularis oculi muscle in all cases and the marginal mandibular branch was distributed to the orbicularis oris muscle in all cases. The zygomatic branch was distributed to the orbicularis oculi muscle in all cases, but it was also distributed to the orbicularis oris muscle in 10 of 25 cases. The buccal branch was not distributed to the orbicularis oris muscle in 3 of 25 cases, and it was distributed to the orbicularis oculi muscle in 8 cases. There was no significant difference in the variations. The orbicularis oculi muscle and orbicularis oris muscle perform particularly important movements among the facial mimetic muscles. According to textbooks, the temporal branch and zygomatic branch innervate the orbicularis oculi muscle, and the buccal branch

  3. Effect of Expiratory Resistive Loading in Expiratory Muscle Strength Training on Orbicularis Oris Muscle Activity

    PubMed Central

    Yanagisawa, Yukio; Matsuo, Yoshimi; Shuntoh, Hisato; Horiuchi, Noriaki

    2014-01-01

    [Purpose] The purpose of this study was to elucidate the effect of expiratory resistive loading on orbicularis oris muscle activity. [Subjects] Subjects were 23 healthy individuals (11 males, mean age 25.5±4.3 years; 12 females, mean age 25.0±3.0 years). [Methods] Surface electromyography was performed to measure the activity of the orbicularis oris muscle during maximum lip closure and resistive loading at different expiratory pressures. Measurement was performed at 10%, 30%, 50%, and 100% of maximum expiratory pressure (MEP) for all subjects. The t-test was used to compare muscle activity between maximum lip closure and 100% MEP, and analysis of variance followed by multiple comparisons was used to compare the muscle activities observed at different expiratory pressures. [Results] No significant difference in muscle activity was observed between maximum lip closure and 100% MEP. Analysis of variance with multiple comparisons revealed significant differences among the different expiratory pressures. [Conclusion] Orbicularis oris muscle activity increased with increasing expiratory resistive loading. PMID:24648644

  4. Electromyographic analysis of upper and lower fascicles of the orbicularis oris muscle in deaf individuals, in mandibular rest position, compared to hearers.

    PubMed

    Regalo, S C H; Vitti, M; Hallak, J E C; Siéssere, S; Pagnano, V O; Semprini, M

    2006-01-01

    This study had the aim to analyze electromyographically, the upper and lower fascicles of the orbicularis oris muscle in bilingual, oralist deaf individuals, comparing them with clinically healthy volunteers in mandibular rest position. This was performed in 50 patients of both sexes with an average age of 18.5 years, divided into 4 groups. 1. Ten deaf bilingual, nasal-breathing patients; 2. Ten deaf bilingual, buccal-breathing patients; 3. Ten deaf oralist, nasal-breathing patients; 4. Twenty healthy volunteers, nasal-breathing patients. An electromyograph K6-I EMG Light Channel Surface Electromyography (Myo-tronics Co. Seattle, WA, EUA) of eight channels was used. The electrodes applied were duotrodes, silver-chloride surface, disposable. Statistical analysis was performed using the SPSS software version 10.0 (Chicago, IL). Continuos data with normal distribution were analyzed by univariate analysis of variance (ANOVA). The level of significance was set at alpha= 0.01. Comparing the EMG activity of the orbicularis oris muscle made it possible to verify that, during clinical mandibular rest position, all four groups presented various levels of electromyographic (EMG) activity with statistically significant differences (F = 8.81, p < 0.01). Based this study's data, it was possible to conclude that the electromyography analysis of the orbicularis oris muscle in deaf individuals showed that deaf individuals presented higher levels of EMG activity of the orbicularis oris muscle than normal controls during mandibular rest position.

  5. ORAL MYOFUNCTIONAL AND ELECTROMYOGRAPHIC EVALUATION OF THE ORBICULARIS ORIS AND MENTALIS MUSCLES IN PATIENTS WITH CLASS II/1 MALOCCLUSION SUBMITTED TO FIRST PREMOLAR EXTRACTION

    PubMed Central

    de Souza, Denize Ramirez; Semeghini, Tatiana Adamov; Kroll, Lucio Benedito; Berzin, Fausto

    2008-01-01

    Objective: The aim of this study was to assess the presence of oral myofunctional alterations before and after first premolar extraction in Class II/1 malocclusion patients that could endanger the long-term dental arch stability. Material and Methods: The study was performed by means of morphological, functional and electromyographic analyses in 17 Class II/1 malocclusion patients (group T) and 17 Class I malocclusion patients (group C -control), both groups with 12-30-year age range (mean age: 20.93 ± 4.94 years). Results: Data analyzed statistically by Student's t-test showed a significant decrease (p<0.05) in the maxillary and mandibular dental arch perimeters after orthodontic treatment, but lip posture at rest did not present statistically significant differences after treatment (p>0.05). The Kruskal-Wallis test analyzed data from lip posture (orbicularis oris muscle) at rest and during swallowing, as well as the mentalis muscle behavior during the above-mentioned function, not showing statistically significant differences (p>0.05) after treatment (groups T1 and T2). However, group T differed significantly from group C (p<0.05). Lip posture during swallowing showed statistically significant differences (p<0.05) for subjects submitted to orthodontic therapy when compared to data acquired before the treatment. The electromyographic analysis confirmed these data. Conclusions: Found myofunctional alterations observed after the orthodontic treatment in Class II/1 malocclusion seemed to jeopardize the long-term orthodontic stability, making recurrence possible. PMID:19089223

  6. A Biomechanical Modeling Study of the Effects of the Orbicularis Oris Muscle and Jaw Posture on Lip Shape

    ERIC Educational Resources Information Center

    Stavness, Ian; Nazari, Mohammad Ali; Perrier, Pascal; Demolin, Didier; Payan, Yohan

    2013-01-01

    Purpose: The authors' general aim is to use biomechanical models of speech articulators to explore how possible variations in anatomical structure contribute to differences in articulatory strategies and phone systems across human populations. Specifically, they investigated 2 issues: (a) the link between lip muscle anatomy and variability in…

  7. Intramuscular haemangioma of the levator anguli oris: a rare case.

    PubMed

    Koltsidopoulos, P; Tsea, M; Kafki, S; Skoulakis, C

    2013-10-01

    Intramuscular haemangiomas are benign malformations of blood vessels occurring in skeletal muscles. Because of the rarity of these lesions, their deep location and variable clinical presentation, they often pose diagnostic difficulties. We herein present the first reported case of intramuscular haemangioma occurring in the levator anguli oris muscle. A 26-year-old man was referred to our Department for evaluation and management of a progressive swelling of the right cheek. Based mainly on the imaging findings, a preoperative diagnosis of intramuscular haemangioma was made and surgery was performed. During intervention, a highly vascular soft tissue mass was identified within the levator anguli oris muscle. The lesion was completely removed via an intraoral approach, and histopathological examination showed an intramuscular haemangioma.

  8. Long-term orbital period behaviour of contact binaries V343 Ori and FZ Ori

    NASA Astrophysics Data System (ADS)

    Yıldırım, Muhammed Faruk; Soydugan, Faruk

    2017-02-01

    In this study, we investigated orbital period variations of two contact binaries V343 Ori and FZ Ori based on published minima times. Using the O-C analysis, it was found that both systems indicate orbital period increase. Mass transfer from less massive component to more massive component was used to explain increases in the orbital periods. On the other hand, the secular changes in their periods can be a sign of the thermal relaxation oscillation. In the O-C diagram of FZ Ori, periodic variations also exist. Cyclic periodic changes can be explained as being the result of a light-travel time effect via a tertiary body around the eclipsing pair. The minimum mass of probable tertiary component around FZ Ori was found to be 0.63 M⊙. In addition, the cyclic variation may be evidence of magnetic activity of the components, which are late-type stars.

  9. Optical monitoring of T Ori requested

    NASA Astrophysics Data System (ADS)

    Waagen, Elizabeth O.

    2013-08-01

    Dr. William Herbst (Wesleyan University) and Rachel Pedersen (Bates College) have requested AAVSO assistance in monitoring the Orion variable T Ori in support of spectroscopy they will be obtaining during September 2013. AAVSO nightly coverage (visual or electronic, not time series) of this star is crucial throughout the month of September. T Ori is one of the first variable stars discovered and varies by up to several magnitudes, but the cause of its variability is not fully known more than a century after its discovery. The project goal is to observe spectral changes accompanying the brightness variations that will shed light on their cause. It is critical to be able to assign a magnitude to each spectrum, so amateur astronomers could make a terrific contribution to this project by more intensively monitoring the star during September. Because of the nebulosity associated with the area around T Ori, observations need to be made very carefully and consistently. When the variable is relatively bright, as in the case of T Ori, a filtered observation is always preferred to an unfiltered one as it is much easier to integrate with data from other observers. Visual observers: be sure to use AAVSO charts. An accuracy of 0.1 or even 0.2 mag as can be achieved by (careful!) visual observers will be sufficient. CCD observers: V magnitude or even unfiltered observations will be most useful. Multicolor photometry could be helpful, but the primary need is for a magnitude estimate. Observations in the AAVSO International Database show T Ori with a visual range of magnitude 9.3-~12.6; recent visual and V magnitudes show it between ~9.7 and 11.9. Finder charts with sequence may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details.

  10. Analysis of the herpes simplex virus type 1 OriS sequence: mapping of functional domains.

    PubMed Central

    Martin, D W; Deb, S P; Klauer, J S; Deb, S

    1991-01-01

    The herpes simplex virus type 1 (HSV-1) OriS region resides within a 90-bp sequence that contains two binding sites for the origin-binding protein (OBP), designated sites I and II. A third presumptive OBP-binding site (III) within OriS has strong sequence similarity to sites I and II, but no sequence-specific OBP binding has yet been demonstrated at this site. We have generated mutations in sites I, II, and III and determined their replication efficiencies in a transient in vivo assay in the presence of a helper virus. Mutations in any one of the sites reduced DNA replication significantly. To study the role of OriS sequence elements in site I and the presumptive site III in DNA replication, we have also generated a series of mutations that span from site I across the presumptive binding site III. These mutants were tested for their ability to replicate and for the ability to bind OBP by using gel shift analyses. The results indicate that mutations across site I drastically reduce DNA replication. Triple-base-pair substitution mutations that fall within the crucial OBP-binding domain, 5'-YGYTCGCACT-3' (where Y represents C or T), show a reduced level of OBP binding and DNA replication. Substitution mutations in site I that are outside this crucial binding sequence show a more detrimental effect on DNA replication than on OBP binding. This suggests that these sequences are required for initiation of DNA replication but are not critical for OBP binding. Mutations across the presumptive OBP-binding site III also resulted in a loss in efficiency of DNA replication. These mutations influenced OBP binding to OriS in gel shift assays, even though the mutated sequences are not contained within known OBP-binding sites. Replacement of the wild-type site III with a perfect OBP-binding site I results in a drastic reduction of DNA replication. Thus, our DNA replication assays and in vitro DNA-binding studies suggest that the binding of the origin sequence by OBP is not the only

  11. Multiple sclerosis in New Zealand Māori.

    PubMed

    Pearson, John F; Alla, Sridhar; Clarke, Glynnis; Taylor, Bruce V; Miller, David H; Richardson, Ann; Mason, Deborah F

    2014-12-01

    The prevalence of MS in New Zealand in 2006 was 73.2 (age standardized per 100,000) while for those with indigenous Māori ancestry it was 3.6 times lower at 20.6. Earlier regional surveys (1968-2001) all reported much lower, or zero, prevalence for Māori than European. There was no evidence for differences in MS between those with and without Māori ancestry in either clinical features or latitude, confirming that Māori ancestry does not produce the reported increase in prevalence with latitude. It is likely that prevalence is increasing in low risk Māori; however, MS prognosis is independent of Māori ancestry.

  12. Analysis of Ori-S sequence of HSV-1: identification of one functional DNA binding domain.

    PubMed Central

    Deb, S; Deb, S P

    1989-01-01

    Using gel retardation assays, we have detected an Ori-S binding activity in the nuclear extract of HSV-1 infected Vero cells. The sequence-specific DNA binding activity seems to be identical to that described by Elias et al. (Proc. Natl. Acad. Sci. USA 83: 6322-6326, 1986). This activity fails to retard a mutant origin DNA that has a 5 bp deletion in the reported protein binding site along with an A to T substitution at a position 16 base-pairs away from the site. This mutant also failed to replicate in a transient replication assay, thus correlating binding of the factor on the origin to replication efficiency. Using crude nuclear extracts as the source of the factor and with the help of footprint and gel retardation analyses, we confirmed that protection is only observed on the preferred site of binding on and near the left arm of the Ori-S palindrome. In order to analyze the sequence specificity of the binding we have generated a set of binding site mutants. Competition experiments with these mutant origins indicate that the sequence 5'-TTCGCACTT-3' is crucial for binding. Images PMID:2541411

  13. ori identity signatures: A latent profile analysis of the types of Māori identity.

    PubMed

    Greaves, Lara M; Houkamau, Carla; Sibley, Chris G

    2015-10-01

    ori are the indigenous peoples of New Zealand. However, the term 'Māori' can refer to a wide range of people of varying ethnic compositions and cultural identity. We present a statistical model identifying 6 distinct types, or 'Māori Identity Signatures,' and estimate their proportion in the Māori population. The model is tested using a Latent Profile Analysis of a national probability sample of 686 Māori drawn from the New Zealand Attitudes and Values Study. We identify 6 distinct signatures: Traditional Essentialists (22.6%), Traditional Inclusives (16%), High Moderates (31.7%), Low Moderates (18.7%), Spiritually Orientated (4.1%), and Disassociated (6.9%). These distinct Identity Signatures predicted variation in deprivation, age, mixed-ethnic affiliation, and religion. This research presents the first formal statistical model assessing how people's identity as Māori is psychologically structured, documents the relative proportion of these different patterns of structures, and shows that these patterns reliably predict differences in core demographics. We identify a range of patterns of Māori identity far more diverse than has been previously proposed based on qualitative data, and also show that the majority of Māori fit a moderate or traditional identity pattern. The application of our model for studying Māori health and identity development is discussed.

  14. 42 CFR 93.402 - ORI allegation assessments.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... RESEARCH MISCONDUCT Responsibilities of the U.S. Department of Health and Human Services Research Misconduct Issues § 93.402 ORI allegation assessments. (a) When ORI receives an allegation of research misconduct directly or becomes aware of an allegation or apparent instance of research misconduct, it...

  15. An oral health intervention for the Māori indigenous population of New Zealand: oranga niho Māori (Māori oral health) as a component of the undergraduate dental curriculum in New Zealand.

    PubMed

    Broughton, John

    2010-06-01

    ori are the Indigenous people of New Zealand having migrated across the Pacific from Hawaiki over a 500 year period from 800AD to 1300AD establishing a society based on whānau (family), hapū (subtribe) and iwi (tribe). Today, like other Indigenous populations throughout the world, New Zealand Māori do not enjoy the same oral health status as non-Māori across all age groups. An intervention strategy to improve Māori oral health and to reduce disparities is to develop a dental health workforce that has an understanding of contemporary Māori society and Māori oral health. The Faculty of Dentistry (Te Kaupeka Pūniho) of the University of Otago has a well developed undergraduate programme in Māori culture and Māori oral health. This programme has been reinforced by the adoption of a new Māori Strategic Framework (MSF) which has been designed to be "a vibrant contributor to Māori development and the realisation of Māori aspirations." Goal 5 of the MSF, Ngā Whakahaerenga Pai (Quality Programmes) has the objective to develop and integrate Māori content in the undergraduate course. This paper will discuss the oranga niho Māori (Māori oral health) component of the undergraduate dental curriculum.

  16. Breast cancer inequities between Māori and non-Māori women in Aotearoa/New Zealand.

    PubMed

    Lawrenson, R; Seneviratne, S; Scott, N; Peni, T; Brown, C; Campbell, I

    2016-03-01

    ori women have one of the highest incidences of breast cancer in the world. This high incidence is generally unexplained although higher rates of obesity and alcohol intake are modifiable risk factors that may be important. Māori women are less likely to attend mammographic breast screening and are likely to be diagnosed with more advanced disease. This is one of the reasons for the excess mortality. Another factor is differences in the treatment pathway. Māori women are more likely to experience delay in receiving treatment, are less likely to receive radiotherapy, are more likely to be treated with a mastectomy and are less likely to adhere to long-term adjuvant endocrine therapy. However, genetic factors in Māori women do not seem to impact significantly on mortality. This review looks at the inequity between Māori and non-Māori women and addresses the causes. It proposes ways of reducing inequity through primary prevention, increased participation in breast screening and greater standardisation of the treatment pathway for women newly diagnosed with breast cancer. We believe that health system improvements will decrease barriers to health care participation for Māori women and suggest that further research into identifying and modifying obstacles within health systems is required.

  17. Alcohol Use and Older Māori in Aotearoa.

    PubMed

    Herbert, Sarah; Stephens, Christine

    2015-01-01

    This study investigated alcohol use, hazardous and binge drinking prevalence, and their relationships to socio-demographic variables in community dwelling older Māori adults in New Zealand. Alcohol use, hazardous drinking, and binge drinking were assessed with the AUDIT-C in a cross-sectional postal survey of 1042 older Māori people randomly selected from the New Zealand Electoral Roll. A total of 41.2% of all participants reported drinking at hazardous levels. Odds ratios from binomial logistic regression showed hazardous drinking was significantly more likely to occur among males, current smokers, and those with higher local self-contained network scores. Binge drinking was reported by 19.6% of the sample, with odds ratios indicating that males, current smokers, and those with higher Māori cultural identification scores were significantly more likely to report binge drinking. The high rates of hazardous and binge drinking prevalence reported in the current study raise issues of concern when considering the health of older Māori people. Results indicate that social networks, gender, smoking status, and Māori cultural identification may influence hazardous and binge drinking alcohol use. However, limitations of the present study also highlight the need for more focused and in-depth research to be conducted with older Māori people to understand the sociocultural context in which alcohol use occurs.

  18. Key informant views on biobanking and genomic research with Māori.

    PubMed

    Hudson, Maui; Southey, Kim; Uerata, Lynley; Beaton, Angela; Milne, Moe; Russell, Khyla; Smith, Barry; Wilcox, Phillip; Toki, Valmaine; Cheung, Melanie

    2016-12-16

    The aim of the Te Mata Ira project was to explore Māori views on biobanking and genomic research, and to identify ways to address Māori concerns over the collection and use of human tissue. Key informant interviews and workshops were conducted with Māori to identify Māori views in relation to biobanking and genomic research; and, informed by these views, interviews and workshops were conducted with Māori and non-Māori key informants (Indigenous Advisory Panel (IAP) members and science communities) to explore key issues in relation to Māori participation in biobanking and genomic research. Māori key informants identified the following as key deliberations: (1) the tension for Māori between previous well-publicised negative experiences with genomic research and the potential value for whānau and communities as technologies develop, (2) protection of Māori rights and interest, (3) focus on Māori health priorities, (4) control of samples and data, (5) expectations of consultation and consent and (6) a desire for greater feedback and communication. Māori and non-Māori key informants highlighted the need to enhance levels of Māori participation in the governance of genomic research and biobanking initiatives, and acknowledged that only by increasing the level of transparency and accountability in relation to these activities will Māori communities feel that their whakapapa, rights and interests are being appropriately protected.

  19. X-ray in Zeta-Ori

    NASA Astrophysics Data System (ADS)

    López-García, M. A.; López-Santiago, J. L.; Albacete-Colombo, J. F.; De Castro, E.

    2013-05-01

    Nearby star-forming regions are ideal laboratories to study high-energy emission processes but they usually present high absorption what makes difficult to detect the stellar population inside the molecular complex. As young late-type stars show high X-ray emission and X-ray photons are little absorbed by interstellar material, X-ray dedicated surveys are an excellent tool to detect the low-mass stellar population in optically absorbed regions. In this work, we present a study of the star-forming region Zeta-Ori and its surroundings. We combine optical, infrared and X-ray data. Properties of the X-ray emiting plasma and infrared features of the young stellar objects detected in the XMM-Newton observation are determined. The southern part of the Orion B giant molecular cloud complex harbor other star forming regions, as NGC 2023 and NGC 2024, we use this regions to compare. We study the spectral energy distribution of X-ray sources. Combining these results with infrared, the X-ray sources are classified as class I, class II and class III objects. The X-ray spectrum and ligth curve of detected X-ray sources is analyzed to found flares. We use a extincion-independent index to select the stars with circumstellar disk, and study the relationship between the present of disk and the flare energy. The results are similar to others studies and we conclude that the coronal properties of class II and class III objects in this region do not differ significantly from each other and from stars of similar infrared class in the ONC.

  20. No clinical or neurophysiological evidence of botulinum toxin diffusion to non-injected muscles in patients with hemifacial spasm.

    PubMed

    Lorenzano, C; Bagnato, S; Gilio, F; Fabbrini, G; Berardelli, A

    2006-04-01

    Botulinum toxin injected into a muscle may diffuse to nearby muscles thus producing unwanted effects. In patients with hemifacial spasm, we evaluated clinically and neurophysiologically, whether botulinum toxin type A (BoNT-A) diffuses from the injection site (orbicularis oculi) to untreated muscles (orbicularis oris from the affected side and orbicularis oculi and oris from the unaffected side). We studied 38 patients with idiopathic hemifacial spasm. Botulinum toxin was injected into the affected orbicularis oculi muscle alone (at 3 standardized sites) at a clinically effective dose. Patients were studied before (T0) and 3-4 weeks after treatment (T1). We evaluated the clinical effects of botulinum toxin and muscle strength in the affected and unaffected muscles. We also assessed the peak-to-peak amplitude compound muscle action potential (CMAP) recorded from the orbicularis oculi and orbicularis oris muscles on both sides after supramaximal electrical stimulation of the facial nerve at the stylomastoid foramen. In all patients, botulinum toxin treatment reduced muscle spasms in the injected orbicularis oculi muscle and induced no muscle weakness in the other facial muscles. The CMAP amplitude significantly decreased in the injected orbicularis oculi muscle, but remained unchanged in the other facial muscles (orbicularis oris muscle on the affected side and contra-lateral unaffected muscles). In conclusion, in patients with hemifacial spasm, botulinum toxin, at a clinically effective dose, induces no clinical signs of diffusion and does not reduce the CMAP size in the nearby untreated orbicularis oris or contralateral facial muscles.

  1. THE HERBIG BE STAR V1818 ORI AND ITS ENVIRONMENT

    SciTech Connect

    Chiang, Hsin-Fang; Reipurth, Bo; Hillenbrand, Lynne E-mail: reipurth@ifa.hawaii.edu

    2015-03-15

    The little-studied Herbig Be star V1818 Ori is located in the direction of the southern L1641 cloud and the Mon R2 star-forming complex, and is most likely associated with the latter at a distance of ∼900 pc. A high-resolution spectrum is consistent with a spectral type around B7 V, with lines of Hα, the red Ca ii triplet, and several forbidden lines in emission. An All Sky Automated Survey V-band light curve spanning 9 yr reveals major variability with deep absorption episodes reminiscent of the UX Orionis stars. We have searched for additional young stars clustering around V1818 Ori using grism images and the 2MASS and Wide-field Infrared Survey Explorer catalogs, and have found almost two dozen fainter stars with evidence of youth. Direct images show that the bright star IRAS 05510–1025, only about 3 arcmin from V1818 Ori, is surrounded by a reflection nebula, indicating its association with a molecular cloud. A spectrum of the star shows no emission-lines, and it is found to be a close binary with late B and early G type components. Its radial velocity indicates that it is an interloper, accidentally passing through the cloud and not physically associated with V1818 Ori.

  2. Rapid variability of the EXor star NY Ori

    NASA Astrophysics Data System (ADS)

    Lorenzetti, D.; Arkharov, A. A.; Efimova, N.; Giannini, T.; Antoniucci, S.; Di Paola, A.; Larionov, V. M.

    2016-03-01

    We report on a rapid brightness variability of the classical EXor star NY Ori observed with the AZT24 1m IR telescope (Campo Imperatore, Italy), as a part of our program EXORCISM (EXOR OptiCal and Infrared Systematic Monitoring - Antoniucci et al. 2013 PPVI; Lorenzetti et al. 2009 ApJ 693, 1056).

  3. 42 CFR 93.402 - ORI allegation assessments.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false ORI allegation assessments. 93.402 Section 93.402 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES...

  4. 42 CFR 93.402 - ORI allegation assessments.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false ORI allegation assessments. 93.402 Section 93.402 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES...

  5. 42 CFR 93.402 - ORI allegation assessments.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false ORI allegation assessments. 93.402 Section 93.402 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES...

  6. 42 CFR 93.402 - ORI allegation assessments.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false ORI allegation assessments. 93.402 Section 93.402 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES...

  7. The Herbig Be Star V1818 Ori and Its Environment

    NASA Astrophysics Data System (ADS)

    Chiang, Hsin-Fang; Reipurth, Bo; Hillenbrand, Lynne

    2015-03-01

    The little-studied Herbig Be star V1818 Ori is located in the direction of the southern L1641 cloud and the Mon R2 star-forming complex, and is most likely associated with the latter at a distance of ˜900 pc. A high-resolution spectrum is consistent with a spectral type around B7 V, with lines of Hα, the red Ca ii triplet, and several forbidden lines in emission. An All Sky Automated Survey V-band light curve spanning 9 yr reveals major variability with deep absorption episodes reminiscent of the UX Orionis stars. We have searched for additional young stars clustering around V1818 Ori using grism images and the 2MASS and Wide-field Infrared Survey Explorer catalogs, and have found almost two dozen fainter stars with evidence of youth. Direct images show that the bright star IRAS 05510-1025, only about 3 arcmin from V1818 Ori, is surrounded by a reflection nebula, indicating its association with a molecular cloud. A spectrum of the star shows no emission-lines, and it is found to be a close binary with late B and early G type components. Its radial velocity indicates that it is an interloper, accidentally passing through the cloud and not physically associated with V1818 Ori.

  8. 42 CFR 93.403 - ORI review of research misconduct proceedings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false ORI review of research misconduct proceedings. 93... POLICIES ON RESEARCH MISCONDUCT Responsibilities of the U.S. Department of Health and Human Services Research Misconduct Issues § 93.403 ORI review of research misconduct proceedings. ORI may conduct...

  9. Varicella-zoster virus (VZV) origin of DNA replication oriS influences origin-dependent DNA replication and flanking gene transcription.

    PubMed

    Khalil, Mohamed I; Sommer, Marvin H; Hay, John; Ruyechan, William T; Arvin, Ann M

    2015-07-01

    The VZV genome has two origins of DNA replication (oriS), each of which consists of an AT-rich sequence and three origin binding protein (OBP) sites called Box A, C and B. In these experiments, the mutation in the core sequence CGC of the Box A and C not only inhibited DNA replication but also inhibited both ORF62 and ORF63 expression in reporter gene assays. In contrast the Box B mutation did not influence DNA replication or flanking gene transcription. These results suggest that efficient DNA replication enhances ORF62 and ORF63 transcription. Recombinant viruses carrying these mutations in both sites and one with a deletion of the whole oriS were constructed. Surprisingly, the recombinant virus lacking both copies of oriS retained the capacity to replicate in melanoma and HELF cells suggesting that VZV has another origin of DNA replication.

  10. Biotechnology: the language of multiple views in Māori communities.

    PubMed

    Te Momo, O H Fiona

    2007-09-01

    In Aotearoa (New Zealand), the government funded studies on communicating biotechnology to different sectors in the community from 2003 to 2006. Subsequently, a researcher covering the Māori sector performed a content analysis of data gathered in the community. Qualitative analysis methods included examining text from participant interviews, focus groups, government documents, newspapers, Internet sites, and current literature. Content was coded by identifying common themes in the English and the Māori language. Words like genetic modification (GM), genetic engineering (GE), and biotechnology were explained to provide a basic understanding between the communities and researcher. The terminology applied in the research was essential to achieve communication between the researcher and the community. The resultant themes represented seven views to interpret the communities association with biotechnology: purist Māori, religious Māori, anti Māori, pro Māori, no Māori, uncertain Māori, and middle Māori views. The themes are taken from the analysis of data compiled after 3 years of completing different stages of a research project. The views indicate that a common understanding can be achieved in the diverse range of Māori tribal communities providing those communicating biotechnology can identify the view and interpretations communities associate with biotechnology. This knowledge is essential for government agencies, researchers, community practitioners, scientist, and businesses that desire to dialogue with Māori communities in the language of biotechnology.

  11. Navigation: process of building relationships with kaumātua (Māori leaders).

    PubMed

    Dyall, Lorna; Skipper, Te Kaanga; Kēpa, Mere; Hayman, Karen; Kerse, Ngaire

    2013-01-25

    In the article the authors depict relations in sociocultural navigation by Māori researchers conducting research embedded in mutual trust; rather than instrumental navigation in linear time. A longitudinal study of Māori and non Māori men and women ageing successfully was planned; this feasibility stage tested whether engaging with kōroua/older Māori men and kuia/older Māori women was possible. We document the process undertaken with Ngā Pae o te Maramatanga New Zealand's Indigenous Centre of Research Excellence (hosted by the University of Auckland) to involve Māori people in the research, engaging with kōroua and kuia aged 75 to 79 years old, developing focus groups to discuss questions specific to te reo Māori me ngā tikanga/Maori language and culture, and building research capacity in Māori tribal and primary health organisations in the Bay of Plenty. In addition, engaging with Te Taura Whiri i te Reo Māori/ Māori Language Commission to translate the questions; recruiting the RopuKaitiaki o Ngā Tikanga Māori/Protectors of Principles of Conduct in Māori Research, and naming the study will be discussed. The involvement of the kaumātua/older Māori people has been fundamental in laying the foundation of the Life and Living in Advanced Age: A Cohort Study in New Zealand (LiLACS NZ), Te Puāwaitanga o Ngā Tapuwae Kia Ora Tonu to study a group of Māori aged 80 to 90 years old.

  12. Oak Ridge Graph Analytics for Medical Innovation (ORiGAMI)

    SciTech Connect

    Roberts, Larry W.; Lee, Sangkeun

    2016-01-01

    In this era of data-driven decisions and discovery where Big Data is producing Bigger Data, data scientists at the Oak Ridge National Laboratory are leveraging unique leadership infrastructure (e.g., Urika XA and Urika GD appliances) to develop scalable algorithms for semantic, logical and statistical reasoning with Big Data (i.e., data stored in databases as well as unstructured data in documents). ORiGAMI is a next-generation knowledge-discovery framework that is: (a) knowledge nurturing (i.e., evolves seamlessly with newer knowledge and data), (b) smart and curious (i.e. using information-foraging and reasoning algorithms to digest content) and (c) synergistic (i.e., interfaces computers with what they do best to help subject-matter-experts do their best. ORiGAMI has been demonstrated using the National Library of Medicine's SEMANTIC MEDLINE (archive of medical knowledge since 1994).

  13. Near-Infrared Spectroscopic Study of V1647 Ori

    NASA Astrophysics Data System (ADS)

    Brittain, Sean D.; Rettig, Terrence W.; Simon, Theodore; Gibb, Erika L.; Liskowsky, Joseph

    2010-01-01

    We present new high-resolution infrared echelle spectra of V1647 Ori, the young star that illuminates McNeil's nebula. From the start, V1647 Ori has been an enigmatic source that has defied classification, in some ways resembling eruptive stars of the FUor class and in other respects the EXor variables. V1647 Ori underwent an outburst in 2003 before fading back to its pre-outburst brightness in 2006. In 2008, it underwent a new outburst. In this paper, we present high-resolution K-band and M-band spectra from the W. M. Keck Observatory that were acquired during the 2008 outburst. We compare the spectra to spectra acquired during the previous outburst and quiescent phases. We find that the luminosity and full width at half maximum power of Br γ increased as the star has brightened and decreased when the star faded, indicating that these phases are driven by variations in the accretion rate. We also show that the temperature of the CO emission has varied with the stellar accretion rate, confirming suggestions from modeling of the heating mechanisms of the inner disk. Finally, we find that the lowest energy blueshifted CO absorption lines originally reported in 2007 are no longer detected. The absence of these lines confirms the short-lived nature of the outflow launched at the start of the quiescent phase in 2006.

  14. Speech-Muscle Visuomotor Tracking in Dysarthric and Nonimpaired Speakers.

    ERIC Educational Resources Information Center

    McClean, Michael D.; And Others

    1987-01-01

    Surface electrodes were used to describe the perioral reflexes in seven stutterers and five nonstutterers and electromyographic (EMG) recordings were obtained at electrode sites associated with the orbicularis oris inferior muscle and the depressor labia inferior muscle. A difference was noted in the pattern of reflex response between the two…

  15. A review of Māori astronomy in Aotearoa-New Zealand

    NASA Astrophysics Data System (ADS)

    Harris, Pauline; Matamua, Rangi; Smith, Takirirangi; Kerr, Hoturoa; Waaka, Toa

    2013-11-01

    Across the world indigenous people are seeking to reclaim their traditional knowledge. Within the last fifty years the Māori of Aotearoa-New Zealand have made significant efforts to reclaim their language, arts and science. Part of this renaissance includes a growing Māori movement to reclaim their astronomical knowledge. Māori astronomical understanding was infused throughout much of pre-colonial Māori life, culture and belief. The Sun, Moon and stars were an integral part of practices pertaining to agriculture, architecture, fishing, calendrical systems and exploration. Although early ethnographers attempted to record this knowledge, their works seem to only reflect a somewhat superficial level of understanding. Thus this paper highlights some of the current research being conducted on Māori astronomy, which seeks a greater understanding of how the ancestors of the Māori perceived the heavens.

  16. Differences in survival between Māori and New Zealand Europeans with prostate cancer.

    PubMed

    Lao, C; Obertová, Z; Brown, C; Scott, N; Edlin, R; Gilling, P; Holmes, M; Tyrie, L; Lawrenson, R

    2016-03-01

    This study aims to examine the survival disparity between Māori men and New Zealand (NZ) Europeans diagnosed with prostate cancer. We identified men aged 40+ years in the Midland Cancer Network region registered with prostate cancer in 2007-2010 in the Cancer Registry. Data were extracted from patient notes of all Māori men and a sample of NZ Europeans. The survival disparity between Māori men and Europeans was estimated by the Kaplan-Meier method and Cox proportional-hazards regression models after adjusting for other factors. This study included 535 men with prostate cancer (135 Māori men and 400 Europeans). The 5-year cancer-specific survival was 98.6% for men diagnosed with localised cancer, 88.8% for locally advanced disease and 19.1% for metastatic cancer. The all-cause survival and the cancer-specific survival were both significantly poorer for Māori men than for NZ Europeans (log rank test: P = 0.004, 0.006 respectively). The hazard ratio of cancer-specific survival for Māori men was 2.01 (95% CI: 1.21-3.36) compared with NZ Europeans. Māori men with prostate cancer had poorer all-cause survival and cancer-specific survival than NZ Europeans. Māori men were at risk of having more advanced disease at diagnosis, which explains most of the survival inequity between Māori men and NZ Europeans.

  17. Relative rates of RNA synthesis across the genome of Epstein-Barr virus are highest near oriP and oriLyt.

    PubMed Central

    Metzenberg, S

    1989-01-01

    The rates of Epstein-Barr virus transcription were measured in isolated nuclei from marmoset and human lymphoblasts transformed in vitro. In B95-8, a marmoset B-lymphoid cell line, the most frequently transcribed viral genes are the EBERs (small nuclear RNAs) and BHLF-1 (encoding a lytic-phase gene product). The EBERs and BHLF-1 genes are separated by nearly 50 kilobase pairs on the Epstein-Barr virus genome and lie adjacent to (less than 300 base pairs from) oriP and oriLyt, respectively. oriP and oriLyt are putative origins of viral DNA replication, and each is associated with a transcriptional enhancer element. Among the human B-lymphoblastoid cell lines tested, only the transcription of EBERs predominates. Images PMID:2552173

  18. Dissonant roles: The experience of Māori in cancer care.

    PubMed

    Dew, Kevin; Signal, Louise; Davies, Cheryl; Tavite, Huia; Hooper, Carolyn; Sarfati, Diana; Stairmand, Jeannine; Cunningham, Chris

    2015-08-01

    Indigenous peoples have poorer health outcomes than their non-indigenous counterparts and this applies to cancer outcomes for Māori in Aotearoa/New Zealand. Differential access to and quality of healthcare contributes to poorer survival rates for Māori. This research provides insight into some of the mechanisms that hinder and facilitate care access. Thirty four people who had undergone cancer treatment (19 Māori and 15 non-Māori) were interviewed by two Māori researchers. The analysis of the interview transcripts was informed by membership categorization analysis. This form of analysis attends to the categories that are used and the activities and characteristics associated with those categories. From this analysis it is argued that the classical patient role, or sick role, inadequately captures the kind of role that some Māori take in relation to their healthcare. Māori can also have culturally specific family (whānau) influences and a greater draw towards alternative approaches to healthcare. Dissonant roles contribute to a different experience for Māori. A better understanding of the categories and roles that are relevant to those who have cancer provides opportunities to attenuate the monocultural impacts of healthcare.

  19. Premature mortality resilience and wellbeing within urban Māori communities.

    PubMed

    Waa, Andrew M; Pearson, Amber L; Ryks, John L

    2017-01-01

    ori (the indigenous peoples of Aotearoa New Zealand) experience of colonisation has negatively affected access to many of the resources (e.g. income, adequate housing) that enable health and well-being. However Māori have actively responded to the challenges they have faced. With the majority of the Māori population now living in urban settings this exploratory study aimed to understand factors contributing to mortality resilience despite exposure to socio-economic adversity with reference to Māori well-being. Resilient urban neighborhoods were defined as those that had lower than expected premature mortality among Māori residents despite high levels of socio-economic adversity. Selected resilience indicators theoretically linked to a Māori well-being framework were correlated with the novel Māori_RINZ resilience index. Of the selected indicators, only exposure to crime showed a clear gradient across the resilience index as predicted by the Māori well-being framework. Future research is needed as unclear trends for other indicators may reflect limitations in the indicators used or the need to develop a more comprehensive measure of well-being.

  20. Near-IR photometric monitoring of FU Ori Type Object 2MASS J06593158-0405277

    NASA Astrophysics Data System (ADS)

    Varricatt, W. P.; Carroll, T.; Moore, E.; Benigni, S.

    2015-05-01

    Maehara, Kojima, and Fujii (ATel #6770) discovered a recent FU Ori-type outburst in 2MASS J06593158-0405277. High resolution spectroscopic follow up by Hillenbrand (ATel #6797) confirmed its FU Ori nature, and discovered P-Cygni profile for H alpha line and blue-shifted absorption for other hydrogen lines.

  1. The complexities of designing therapy for Māori living with stroke-related communication disorders.

    PubMed

    Brewer, Karen M

    2016-05-27

    Stroke-related communication disorders can have a substantial impact on Māori whānau (extended family). Timely and appropriate speech-language therapy is required, but there are many challenges in providing this. In this article we discuss the need for a kaupapa Māori approach to speech-language therapy that is designed by Māori for Māori, and undertaken in a Māori way. We report the results of a literature review that revealed a small but significant body of literature describing Māori experiences of stroke, aphasia and speech-language therapy, and evidence that a Māori-specific therapy programme can improve outcomes for people with stroke. We then consider the social and political context that impacts the design and delivery of such an approach. Informed by the literature, we propose a hierarchy of skill and resource acquisition for speech-language therapists, in which they learn why to be culturally safe, how to be culturally safe, and how to interact before creating resources to build relationships, resources for education and for therapy. The creation of a kaupapa Māori speech-language therapy approach should bring together people with stroke, whānau members and service providers to create therapy that crosses sectors and disciplines and acknowledges the wider social and political context.

  2. In vivo mutagenesis reveals that OriL is essential for mitochondrial DNA replication

    PubMed Central

    Wanrooij, Sjoerd; Miralles Fusté, Javier; Stewart, James B; Wanrooij, Paulina H; Samuelsson, Tore; Larsson, Nils-Göran; Gustafsson, Claes M; Falkenberg, Maria

    2012-01-01

    The mechanisms of mitochondrial DNA replication have been hotly debated for a decade. The strand-displacement model states that lagging-strand DNA synthesis is initiated from the origin of light-strand DNA replication (OriL), whereas the strand-coupled model implies that OriL is dispensable. Mammalian mitochondria cannot be transfected and the requirements of OriL in vivo have therefore not been addressed. We here use in vivo saturation mutagenesis to demonstrate that OriL is essential for mtDNA maintenance in the mouse. Biochemical and bioinformatic analyses show that OriL is functionally conserved in vertebrates. Our findings strongly support the strand-displacement model for mtDNA replication. PMID:23090476

  3. The photometric variability of ζ Ori Aa observed by BRITE* **

    NASA Astrophysics Data System (ADS)

    Buysschaert, B.; Neiner, C.

    2016-12-01

    Using BRITE photometry, we investigated the photometric variability of the magnetic O-type supergiant ζOri Aa. We found two independent frequencies, leading to several higher harmonics and simple linear combinations. One frequency is related to the rotation period, f_{rot} = 0.15±0.02 d^{-1}. The derived rotation period from this frequency and its higher harmonics, P_{rot} = 6.65±0.28 d, is compatible with the literature value (P_{rot} = 6.83±0.08 d). Thanks to simultaneous CHIRON spectroscopy, we locate the origin of the second frequency, f_{env} = 0.10±0.02 d^{-1}, at the circumstellar environment. We propose mass-loss events as the underlying origin.

  4. Mechanics of Miura-ori Origami Lattice Defects

    NASA Astrophysics Data System (ADS)

    Silverberg, Jesse; McLeod, Lauren; Evans, Arthur; Ginepro, Jessica; Santangelo, Christian; Hull, Thomas; Cohen, Itai

    2014-03-01

    The mechanical properties of origami-inspired materials show remarkable potential for responsive, tunable next-generation materials. For example, the Miura-ori fold is predicted to have negative Poisson ratio and anisotropic compressive properties. Using a custom mechanical testing device and 3D laser profilometry, we investigate the moduli and the role of curvature in setting these material properties. Because defects are known to dramatically alter the bulk properties in other periodic materials, we introduce defects into the folding pattern to investigate their effects on the macroscopic mechanical properties. Interestingly, we find that a single defect increases the overall material stiffness, but the introduction of a second defect in the opposite direction can cancel out the first, tending to restore the original material properties. Moreover, these defect pairs can be arranged to form edge dislocations, grain boundaries, and many other topological configurations familiar from the study of crystallographic lattice defects.

  5. Differential polarization direct imaging of FU Ori type YSO

    NASA Astrophysics Data System (ADS)

    Fu, Guangwei; Takami, Michihiro; Scicluna, Peter; Karr, Jennifer

    2017-01-01

    FU Orionis objects (FUors) are distinguished from other young stellar objects due to their outbursts. They can surge in brightness by multiple magnitudes in a short time. Thus FUors have always been considered the strongest evidence which suggests unsteady accretion process in low mass young stellar objects (YSO). However the accreting process of FUors are not well understood. We present high resolution (~0.1 arcseconds) observations of 5 FUors (FU Ori, V1057cyg, V1515cyg, V1735cyg, Z Cma) in near infrared bandpasses (J,H,K) using the Subaru telescope. Through using polarization differential imaging and coronagraphy techniques, we were able to obtain high contrast images of circumstellar environment around central young stars. After image processing, we found interesting structures (stream, tail, fragment, etc) in the circumstellar disks. These structures are indications for dynamical interaction, potential outflow cavities and disk fragmentation. More importantly, these disk features can provide us with insight into the accretion process and where outbursts originate.

  6. Dependence on place: A source of autonomy in later life for older Māori.

    PubMed

    Butcher, Elizabeth; Breheny, Mary

    2016-04-01

    Attachment to place is an important component of ageing. Although the importance of place for older people's well-being is known, the ways in which different conceptions of place and expectations for what later life may hold depend upon cultural beliefs, values, and expectations is underexplored. This study examined the ways that place influences experiences of ageing for older Māori in New Zealand. Eight interviews with older Māori were analysed thematically alongside field notes from a research visit. Attachment to place provided the foundation for experiences of ageing for older Māori. Through their connection to place, the participants drew on a comforting and comfortable dependence on land and family to enable autonomy in later life. Rather than seeking to maintain independence in terms of avoiding reliance on others, older Māori conceptualised older age through autonomy and freedom to live in accordance with Māori values encapsulated by whakawhanaungatanga. A good old age depended on balancing competing demands of living in wider society with attachment to place and Māori identity in later life.

  7. Fu Ori outbursts and the planet-disc mass exchange

    NASA Astrophysics Data System (ADS)

    Nayakshin, Sergei; Lodato, Giuseppe

    2012-10-01

    It has been recently proposed that giant protoplanets migrating inwards through the disc more rapidly than they contract could be tidally disrupted when they fill their Roche lobes ˜0.1 au away from their parent protostars. Here we consider the process of mass and angular momentum exchange between the tidally disrupted planet and the surrounding disc in detail. We find that the planet's adiabatic mass-radius relation and its ability to open a deep gap in the disc determine whether the disruption proceeds as a sudden runaway or a balanced quasi-static process. In the latter case, the planet feeds the inner disc through its Lagrangian L1 point like a secondary star in a stellar binary system. As the planet loses mass, it gains specific angular momentum and normally migrates in the outward direction until the gap closes. Numerical experiments show that planet disruption outbursts are preceded by long 'quiescent' periods during which the disc inward of the planet is empty. The hole in the disc is created when the planet opens a deep gap, letting the inner disc to drain on to the star while keeping the outer one stalled behind the planet. We find that the mass-losing planet embedded in a realistic protoplanetary disc spawns an extremely rich set of variability patterns. In a subset of parameter space, there is a limit cycle behaviour caused by non-linear interaction between the planet mass-loss and the disc hydrogen ionization instability. We suggest that tidal disruptions of young massive planets near their stars may be responsible for the observed variability of young accreting protostars such as FU Ori, EXor and T Tauri stars in general.

  8. Predictors of academic success for Māori, Pacific and non-Māori non-Pacific students in health professional education: a quantitative analysis.

    PubMed

    Wikaire, Erena; Curtis, Elana; Cormack, Donna; Jiang, Yannan; McMillan, Louise; Loto, Rob; Reid, Papaarangi

    2017-05-01

    Tertiary institutions internationally aim to increase student diversity, however are struggling to achieve equitable academic outcomes for indigenous and ethnic minority students and detailed exploration of factors that impact on success is required. This study explored the predictive effect of admission variables on academic outcomes for health professional students by ethnic grouping. Kaupapa Māori and Pacific research methodologies were used to conduct a quantitative analysis using data for 2686 health professional students [150 Māori, 257 Pacific, 2279, non-Māori non-Pacific (nMnP)]. The predictive effect of admission variables: school decile; attending school in Auckland; type of admission; bridging programme; and first-year bachelor results on academic outcomes: year 2-4 grade point average (GPA); graduating; graduating in the minimum time; and optimal completion for the three ethnic groupings and the full cohort was explored using multiple regression analyses. After adjusting for admission variables, for every point increase in first year bachelor GPA: year 2-4 GPA increased by an average of 0.46 points for Māori (p = 0.0002, 95% CI 0.22, 0.69), 0.70 points for Pacific (p < 0.0001, CI 0.52, 0.87), and 0.55 points for nMnP (p < 0.0001, CI 0.51, 0.58) students. For the total cohort, ethnic grouping was consistently the most significant predictor of academic outcomes. This study demonstrated clear differences in academic outcomes between both Māori and Pacific students when compared to nMnP students. Some (but not all) of the disparities between ethnic groupings could be explained by controlling for admission variables.

  9. oriC-encoded instructions for the initiation of bacterial chromosome replication

    PubMed Central

    Wolański, Marcin; Donczew, Rafał; Zawilak-Pawlik, Anna; Zakrzewska-Czerwińska, Jolanta

    2014-01-01

    Replication of the bacterial chromosome initiates at a single origin of replication that is called oriC. This occurs via the concerted action of numerous proteins, including DnaA, which acts as an initiator. The origin sequences vary across species, but all bacterial oriCs contain the information necessary to guide assembly of the DnaA protein complex at oriC, triggering the unwinding of DNA and the beginning of replication. The requisite information is encoded in the unique arrangement of specific sequences called DnaA boxes, which form a framework for DnaA binding and assembly. Other crucial sequences of bacterial origin include DNA unwinding element (DUE, which designates the site at which oriC melts under the influence of DnaA) and binding sites for additional proteins that positively or negatively regulate the initiation process. In this review, we summarize our current knowledge and understanding of the information encoded in bacterial origins of chromosomal replication, particularly in the context of replication initiation and its regulation. We show that oriC encoded instructions allow not only for initiation but also for precise regulation of replication initiation and coordination of chromosomal replication with the cell cycle (also in response to environmental signals). We focus on Escherichia coli, and then expand our discussion to include several other microorganisms in which additional regulatory proteins have been recently shown to be involved in coordinating replication initiation to other cellular processes (e.g., Bacillus, Caulobacter, Helicobacter, Mycobacterium, and Streptomyces). We discuss diversity of bacterial oriC regions with the main focus on roles of individual DNA recognition sequences at oriC in binding the initiator and regulatory proteins as well as the overall impact of these proteins on the formation of initiation complex. PMID:25610430

  10. ORBITAL AND PHYSICAL PROPERTIES OF THE σ Ori Aa, Ab, B TRIPLE SYSTEM

    SciTech Connect

    Simón-Díaz, S.; Caballero, J. A.; Apellániz, J. Maíz; Lorenzo, J.; Negueruela, I.; Dorda, R.; Marco, A.; Schneider, F. R. N.; Barbá, R. H.; Montes, D.; Pellerin, A.; Sanchez-Bermudez, J.; Sota, A.

    2015-02-01

    We provide a complete characterization of the astrophysical properties of the σ Ori Aa, Ab, B hierarchical triple system and an improved set of orbital parameters for the highly eccentric σ Ori Aa, Ab spectroscopic binary. We compiled a spectroscopic data set comprising 90 high-resolution spectra covering a total time span of 1963 days. We applied the Lehman-Filhés method for a detailed orbital analysis of the radial velocity curves and performed a combined quantitative spectroscopic analysis of the σ Ori Aa, Ab, B system by means of the stellar atmosphere code FASTWIND. We used our own plus other available information on photometry and distance to the system for measuring the radii, luminosities, and spectroscopic masses of the three components. We also inferred evolutionary masses and stellar ages using the Bayesian code BONNSAI. The orbital analysis of the new radial velocity curves led to a very accurate orbital solution of the σ Ori Aa, Ab pair. We provided indirect arguments indicating that σ Ori B is a fast-rotating early B dwarf. The FASTWIND+BONNSAI analysis showed that the Aa, Ab pair contains the hottest and most massive components of the triple system while σ Ori B is a bit cooler and less massive. The derived stellar ages of the inner pair are intriguingly younger than the one widely accepted for the σ Orionis cluster, at 3 ± 1 Ma. The outcome of this study will be of key importance for a precise determination of the distance to the σ Orionis cluster, the interpretation of the strong X-ray emission detected for σ Ori Aa, Ab, B, and the investigation of the formation and evolution of multiple massive stellar systems and substellar objects.

  11. The nurse's role in improving health disparities experienced by the indigenous Māori of New Zealand.

    PubMed

    Theunissen, Katherine Evelyn

    2011-10-01

    Many countries across the globe experience disparities in health between their indigenous and non-indigenous people. The indigenous Māori of New Zealand are the most marginalized and deprived ethnic group with the poorest health status overall. Factors including the historical British colonization, institutional discrimination, healthcare workforce bias and the personal attitudes and beliefs of Māori significantly contribute to disparities, differential access and receipt of quality health services. Māori experience more barriers towards accessing health services and as a result achieve poorer health outcomes. Contradicting translations of Te Tiriti o Waitangi have created much debate regarding social rights as interpreted by Oritetanga (equal British citizenship rights) and whether or not Māori are entitled to equal opportunities or equal outcomes. Inconsistent consideration of Māori culture in the New Zealand health system and social policy greatly contributes to the current health disparities. Nurses and healthcare professionals alike have the gifted opportunity to truly change attitudes toward Māori health and move forward in adopting culturally appropriate care practices. More specifically the nursing workforce provides 80% of direct patient care, thus are in a unique position to be the forefront of change in reducing health disparities experienced by Māori. Incorporating cultural safety, patient advocacy, and Māori-centred models of care will support nurses in adopting a new approach toward improving Māori health outcomes overall.

  12. A Star-forming Ring around κ Ori 250 pc from the Sun

    NASA Astrophysics Data System (ADS)

    Pillitteri, I.; Wolk, S. J.; Megeath, S. T.

    2016-04-01

    X-rays are a powerful probe of activity in early stages of star formation. They allow us to identify young stars even after they have lost the IR signatures of circumstellar disks and provide constraints on their distance. Here, we report on XMM-Newton observations that detect 121 young stellar objects (YSOs) in two fields between L1641 S and κ Ori. These observations extend the Survey of Orion A with XMM and Spitzer (SOXS). The YSOs are contained in a ring of gas and dust apparent at millimeter wavelengths, and in far-IR and near-IR surveys. The X-ray luminosity function of the YSOs detected in the two fields indicates a distance of 250-280 pc, much closer than the Orion A cloud and similar to distance estimates of κ Ori. We propose that the ring is a 5-8 pc diameter shell that has been swept up by κ Ori. This ring contains several groups of stars detected by Spitzer and WISE including one surrounding the Herbig Ae/Be stars V1818 Ori. In this interpretation, the κ Ori ring is one of several shells swept up by massive stars within the Orion Eridanus Superbubble and is unrelated to the southern portion of Orion A/L1641 S.

  13. A STAR-FORMING RING AROUND κ Ori 250 pc FROM THE SUN

    SciTech Connect

    Pillitteri, I.; Wolk, S. J.; Megeath, S. T.

    2016-04-01

    X-rays are a powerful probe of activity in early stages of star formation. They allow us to identify young stars even after they have lost the IR signatures of circumstellar disks and provide constraints on their distance. Here, we report on XMM-Newton observations that detect 121 young stellar objects (YSOs) in two fields between L1641 S and κ Ori. These observations extend the Survey of Orion A with XMM and Spitzer (SOXS). The YSOs are contained in a ring of gas and dust apparent at millimeter wavelengths, and in far-IR and near-IR surveys. The X-ray luminosity function of the YSOs detected in the two fields indicates a distance of 250–280 pc, much closer than the Orion A cloud and similar to distance estimates of κ Ori. We propose that the ring is a 5–8 pc diameter shell that has been swept up by κ Ori. This ring contains several groups of stars detected by Spitzer and WISE including one surrounding the Herbig Ae/Be stars V1818 Ori. In this interpretation, the κ Ori ring is one of several shells swept up by massive stars within the Orion Eridanus Superbubble and is unrelated to the southern portion of Orion A/L1641 S.

  14. GHRS Observations of the Interstellar Medium toward 23 ORI

    NASA Astrophysics Data System (ADS)

    Welty, D. E.; Hobbs, L. M.; Lauroesch, J. T.; Morton, D. C.; Spitzer, L.; York, D. G.

    1996-05-01

    High-resolution optical spectra, GHRS echelle and G160M spectra, and Copernicus spectra are combined to study the abundances and physical conditions in the diffuse interstellar clouds seen toward 23 Ori. High-resolution (0.3--2.0 km s(-1) ) spectra of Na I, Ca I, Ca II, and K I are used to define the underlying component structure that is unresolved in the UV spectra, enabling more accurate individual cloud abundances and physical conditions to be derived from the numerous transitions found in the UV. Multiple absorption components are present for each of several distinct types of gas. Strong low-velocity (SLV) absorption, due to cool, moderately dense neutral gas, is seen for neutral and singly ionized species at 20 km s(-1) la vsun la 30 km s(-1) . Weaker low-velocity (WLV) absorption, probably due to warmer gas, is seen primarily for singly ionized species at 0 km s(-1) la vsun la 20 km s(-1) . Weak absorption from C II, Mg II, and Si III is seen at -45 km s(-1) la vsun la 0 km s(-1) , and from more highly ionized species at -5 km s(-1) la vsun la 25 km s(-1) . Absorption from singly and doubly ionized species is seen at -110 km s(-1) la vsun la -80 km s(-1) ; this apparently shock-ionized gas is not in collisional ionization equilibrium, having cooled more quickly than it could recombine. The various types of gas present along this line of sight are characterized by different relative abundance / depletion patterns; these depletion patterns are compared with the physical conditions derived for the different components. For the SLV components, most typically depleted species are less depleted by factors of 2--4, compared to the ``cold, dense cloud'' pattern found, for example, toward zeta Oph. The depletions in the WLV gas are typically another factor of 2--3 less than in the SLV gas, similar to the ``warm cloud'' pattern seen in less reddened lines of sight. While there is some uncertainty, due to unobserved ionization stages, as to the depletions in the high

  15. Your Muscles

    MedlinePlus

    ... Room? What Happens in the Operating Room? Your Muscles KidsHealth > For Kids > Your Muscles A A A ... and skeletal (say: SKEL-uh-tul) muscle. Smooth Muscles Smooth muscles — sometimes also called involuntary muscles — are ...

  16. Radial-velocity variations in Alpha Ori, Alpha Sco, and Alpha Her

    SciTech Connect

    Smith, M.A.; Patten, B.M.; Goldberg, L. Computer Sciences Corp., Seabrook, MD Iowa State Univ., Ames )

    1989-12-01

    Radial-velocity observations of Alpha Ori, Alpha Sco A, and Alpha Her A are used to study radial-velocity periodicities in M supergiants. The data refer to several metallic lines in the H-alpha region and to H-alpha itself. It is shown that Alpha Ori and Alpha Sco A have cycle lengths of about 1 yr and semiamplitudes of 2 km/s. It is suggested that many semiregular red supergiant varibles such as Alpha Ori may be heading toward chaos. All three stars show short-term stochastic flucutations with an amplitude of 1-2 km/s. It is found that the long-term variability of H-alpha velocities may be a consequence of intermittent failed ejections. 58 refs.

  17. The experience and impact of gout in Māori and Pacific people: a prospective observational study.

    PubMed

    Dalbeth, Nicola; House, Meaghan E; Horne, Anne; Te Karu, Leanne; Petrie, Keith J; McQueen, Fiona M; Taylor, William J

    2013-02-01

    Although high prevalence of gout in Māori and Pacific people is well-documented, the experience of disease in these groups has not been explored in detail. The aim of this analysis was to describe the experience and impact of gout in Māori and Pacific people. Patients with gout for <10 years were recruited from primary and secondary care settings into a prospective observational study (n = 291; 37 Māori, 35 Pacific, and 219 not Māori or Pacific). Participants attended a baseline study visit which included a comprehensive clinical assessment. Serum urate, flare frequency and activity limitation were recorded at baseline and after 1 year. Māori and Pacific participants had earlier age of onset (by 9 years), higher flare frequency and more features of joint inflammation. Serum urate concentrations were higher in the Māori and Pacific patients at baseline, despite greater use of allopurinol. Māori and Pacific patients reported greater pain and activity limitation and lower health-related quality of life. The cost of gout treatment was more than three times higher in the Māori and Pacific patients. After 1 year, the higher flare frequency and activity limitation persisted in the Māori and Pacific patients. Māori and Pacific people with gout experience early onset, severe disease with frequent flares and poorly controlled hyperuricaemia. Māori and Pacific ethnicity should be recognised as a prognostic factor for more severe outcomes in this disease, and intensive efforts should be made to work with these patients to control serum urate and prevent flares.

  18. Pounamu: E Hine: access to contraception for indigenous Mãori teenage mothers.

    PubMed

    Lawton, Beverley; Makowharemahihi, Charrissa; Cram, Fiona; Robson, Bridget; Ngata, Tina

    2016-03-01

    INTRODUCTION Timely and equitable access to contraception enables teenage mothers to make informed choices about their sexual and reproductive health. This study aimed to identify barriers and facilitators to contraception for Māori teenagers who become mothers. METHODS 'E Hine' is a longitudinal qualitative Kaupapa Māori (by Māori for Māori) study involving Māori women (aged 14-19 years), following them through pregnancy (n = 44) and the birth of their babies until their babies' first birthdays (n = 41). This analysis focusses on contraception access pre-and post-pregnancy. FINDINGS Pre-pregnancy most participants accessed contraception or advice. Contraception use was compromised by a lack of information, negative side effects, and limited follow up. All reported their subsequent pregnancies as unplanned. Participants gave considerable thought to post-pregnancy contraception. Despite this many experienced clinical and service delays, financial barriers, and negative contraceptive side effects. There was little focus on contraception initiation and a lack of integrated care between midwives and other primary care services, leaving many participants without timely effective contraception. The system worked well when there was a contraception plan that included navigation, free access, and provision of contraception. CONCLUSION The majority of participants actively sought contraception pre- and post-conception. Despite a publicly funded system, a lack of health sector integration resulted in multiple missed opportunities to meet the needs of these teenagers for effective contraception. Health service funding formulas should define the goal as initiation of contraception rather than advice and provide funding to improve timely access to long acting reversible contraception. KEYWORDS Indigenous teenage pregnancy; contraception; barriers to contraception; Māori mothers.

  19. 78 FR 49507 - OriGen Energy LLC ; Supplemental Notice That Initial Market-Based Rate Filing Includes Request...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-14

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission OriGen Energy LLC ; Supplemental Notice That Initial Market-Based Rate...-referenced proceeding of OriGen Energy LLC's application for market-based rate authority, with...

  20. Looking Māori Predicts Decreased Rates of Home Ownership: Institutional Racism in Housing Based on Perceived Appearance

    PubMed Central

    2015-01-01

    This study examined differences in rates of home ownership among Māori (the indigenous peoples of New Zealand). We identified systematic factors that predicted why some Māori were more likely to own their own home (partially or fully) relative to other Māori. Data were drawn from a large national postal sample of 561 self-identified Māori collected as part of the New Zealand Attitudes and Values Study. As predicted, our analyses indicated that self-reported appearance as Māori, or the extent to which people thought they personally displayed features which visibly identified them as Māori to others, significantly predicted decreased rates of home ownership. This association held when adjusting for numerous demographic covariates, such as education, level of deprivation of the immediate area, household income, age, relationship status, region of residence, and so forth. Our analyses suggest there is, or at least has been in the recent past, institutional racism against Māori in New Zealand’s home lending industry based on merely appearing more Māori. PMID:25738961

  1. New Zealand youth that sexually offend: improving outcomes for Māori rangatahi and their whānau.

    PubMed

    Lim, Stacey; Lambie, Ian; Cooper, Erana

    2012-10-01

    ori youth are overrepresented in criminal justice statistics and youth forensic services. Māori youth that engage in sexual offending behaviors have a higher risk of dropping out of treatment than Pākehā(1) youth. Research into Māori mental health is important to inform ongoing service development and is essential to strive for equity in mental health outcomes and offending rates among Māori. In this study, the researchers investigated the coexisting emotional and behavioral problems and victimization histories of an age-matched sample of Māori (n = 75) and Pākehā (n = 75) youth who were referred to a community treatment program for sexual offending in Auckland between 1996 and 2008. The Child Behavior Checklist was used to investigate ethnic differences. After controlling for socioeconomic deprivation, Māori youth scored significantly higher than Pākehā youth on the Delinquent Behaviors syndrome scale. Māori youth were also more likely than Pākehā youth to have a background of physical abuse. Implications of these findings are discussed, with regard to the unique needs of Māori youth and appropriate interventions.

  2. ORNL’s ORiGAMI Uses Big Data to Help Solve Age-Old Medical Mysteries in Seconds

    SciTech Connect

    Sukumar, Rangan

    2016-06-17

    ORiGAMI is a tool for discovering and evaluating potentially interesting associations and creating novel hypothesis in medicine. ORiGAMI will help you “connect the dots” across 70 million knowledge nuggets published in 23 million papers in the medical literature.

  3. Looking Māori predicts decreased rates of home ownership: institutional racism in housing based on perceived appearance.

    PubMed

    Houkamau, Carla A; Sibley, Chris G

    2015-01-01

    This study examined differences in rates of home ownership among Māori (the indigenous peoples of New Zealand). We identified systematic factors that predicted why some Māori were more likely to own their own home (partially or fully) relative to other Māori. Data were drawn from a large national postal sample of 561 self-identified Māori collected as part of the New Zealand Attitudes and Values Study. As predicted, our analyses indicated that self-reported appearance as Māori, or the extent to which people thought they personally displayed features which visibly identified them as Māori to others, significantly predicted decreased rates of home ownership. This association held when adjusting for numerous demographic covariates, such as education, level of deprivation of the immediate area, household income, age, relationship status, region of residence, and so forth. Our analyses suggest there is, or at least has been in the recent past, institutional racism against Māori in New Zealand's home lending industry based on merely appearing more Māori.

  4. Thermal imaging of the FU Ori type object 2MASS J06593158-0405277 = V960 Mon

    NASA Astrophysics Data System (ADS)

    Varricatt, W. P.; Kerr, T. H.; Carroll, T.; Moore, E.; Milne, P.

    2015-10-01

    A FU Ori-type outburst of 2MASS J06593158-0405277 (V960 Mon) was discovered by Maehara, Kojima and Fujii (ATel #6770). Further observational studies (ATel #6797, #6838, #6862, #6901, #7025, #7578) and archival data research (Jurdana- & #138;epi & #263; & Munari, 2016, NewA, 43, 87) confirmed the FU Ori nature of this object.

  5. The multi-dimensional model of Māori identity and cultural engagement: item response theory analysis of scale properties.

    PubMed

    Sibley, Chris G; Houkamau, Carla A

    2013-01-01

    We argue that there is a need for culture-specific measures of identity that delineate the factors that most make sense for specific cultural groups. One such measure, recently developed specifically for Māori peoples, is the Multi-Dimensional Model of Māori Identity and Cultural Engagement (MMM-ICE). Māori are the indigenous peoples of New Zealand. The MMM-ICE is a 6-factor measure that assesses the following aspects of identity and cultural engagement as Māori: (a) group membership evaluation, (b) socio-political consciousness, (c) cultural efficacy and active identity engagement, (d) spirituality, (e) interdependent self-concept, and (f) authenticity beliefs. This article examines the scale properties of the MMM-ICE using item response theory (IRT) analysis in a sample of 492 Māori. The MMM-ICE subscales showed reasonably even levels of measurement precision across the latent trait range. Analysis of age (cohort) effects further indicated that most aspects of Māori identification tended to be higher among older Māori, and these cohort effects were similar for both men and women. This study provides novel support for the reliability and measurement precision of the MMM-ICE. The study also provides a first step in exploring change and stability in Māori identity across the life span. A copy of the scale, along with recommendations for scale scoring, is included.

  6. Neoliberalism and indigenous knowledge: Māori health research and the cultural politics of New Zealand's "National Science Challenges".

    PubMed

    Prussing, Erica; Newbury, Elizabeth

    2016-02-01

    In 2012-13 the Ministry of Business, Innovation and Employment (MBIE) in New Zealand rapidly implemented a major restructuring of national scientific research funding. The "National Science Challenges" (NSC) initiative aims to promote greater commercial applications of scientific knowledge, reflecting ongoing neoliberal reforms in New Zealand. Using the example of health research, we examine the NSC as a key moment in ongoing indigenous Māori advocacy against neoliberalization. NSC rhetoric and practice through 2013 moved to marginalize participation by Māori researchers, in part through constructing "Māori" and "science" as essentially separate arenas-yet at the same time appeared to recognize and value culturally distinctive forms of Māori knowledge. To contest this "neoliberal multiculturalism," Māori health researchers reasserted the validity of culturally distinctive knowledge, strategically appropriated NSC rhetoric, and marshalled political resources to protect Māori research infrastructure. By foregrounding scientific knowledge production as an arena of contestation over neoliberal values and priorities, and attending closely to how neoliberalizing tactics can include moves to acknowledge cultural diversity, this analysis poses new questions for social scientific study of global trends toward reconfiguring the production of knowledge about health. Study findings are drawn from textual analysis of MBIE documents about the NSC from 2012 to 2014, materials circulated by Māori researchers in the blogosphere in 2014, and ethnographic interviews conducted in 2013 with 17 Māori health researchers working at 7 sites that included university-based research centers, government agencies, and independent consultancies.

  7. ori experiences of aphasia therapy: "But I'm from Hauiti and we've got shags".

    PubMed

    McLellan, Karen M; McCann, Clare M; Worrall, Linda E; Harwood, Matire L N

    2014-10-01

    This study explored Māori experiences of aphasia therapy, with a view to ascertaining what makes a service culturally safe as well as "accessible to and culturally appropriate for" Māori with aphasia and their whānau (extended family). Māori are the indigenous peoples of New Zealand. This study incorporated interpretive description (a qualitative methodology) within kaupapa Māori research (a Māori approach to research). In-depth semi-structured interviews were undertaken with 11 Māori with aphasia and 23 of their nominated whānau members. They reported a wide variety of experiences of aphasia therapy, in six themes: We're happy to do the work, but we can't do it alone; Relationship; Our worldview; The speech-language therapy setting; Aphasia resources; and Is this as good as it gets? While some Māori with aphasia reportedly received an accessible and culturally appropriate service, others did not. It is concluded that, for Māori with aphasia, a strong therapeutic relationship is central. The success of this relationship is shaped by the SLP's appreciation of the worldview of the person with aphasia and whānau, the setting of the therapy, and the resources used. Successful therapy will involve collaboration between clinician and whānau, and therapy resources that affirm the identity of the person with aphasia.

  8. Insanity and ethnicity in New Zealand: Māori encounters with the Auckland Mental Hospital, 1860-1900.

    PubMed

    Barry, Lorelle; Coleborne, Catharine

    2011-09-01

    This article examines Māori patients at the Auckland Mental Hospital between 1860 and 1900.We argue that the patient case notes reveal 'European' categories in which Māori were situated, and demonstrate the extent to which the authorities at the hospital grappled with their appearance, their language and their culture, all of which were elements of their ethnicity. We argue that the use of institutional case records is highly suggestive of some of the historical meanings of insanity for Māori, including the lack of detailed or sustained collection of information about patients' tribal affiliations, the interest shown in their rights to land in maintenance payment inquiries, the experiences of cultural alienation or mate Māori, and the sad outcomes for Māori.

  9. Differentiation of the DnaA-oriC subcomplex for DNA unwinding in a replication initiation complex.

    PubMed

    Ozaki, Shogo; Noguchi, Yasunori; Hayashi, Yasuhisa; Miyazaki, Erika; Katayama, Tsutomu

    2012-10-26

    In Escherichia coli, ATP-DnaA multimers formed on the replication origin oriC promote duplex unwinding, which leads to helicase loading. Based on a detailed functional analysis of the oriC sequence motifs, we previously proposed that the left half of oriC forms an ATP-DnaA subcomplex competent for oriC unwinding, whereas the right half of oriC forms a distinct ATP-DnaA subcomplex that facilitates helicase loading. However, the molecular basis for the functional difference between these ATP-DnaA subcomplexes remains unclear. By analyzing a series of novel DnaA mutants, we found that structurally distinct DnaA multimers form on each half of oriC. DnaA AAA+ domain residues Arg-227 and Leu-290 are specifically required for oriC unwinding. Notably, these residues are required for the ATP-DnaA-specific structure of DnaA multimers in complex with the left half of oriC but not for that with the right half. These results support the idea that the ATP-DnaA multimers formed on oriC are not uniform and that they can adopt different conformations. Based on a structural model, we propose that Arg-227 and Leu-290 play a crucial role in inter-ATP-DnaA interaction and are a prerequisite for the formation of unwinding-competent DnaA subcomplexes on the left half of oriC. These residues are not required for the interaction with DnaB, nucleotide binding, or regulatory DnaA-ATP hydrolysis, which further supports their important role in inter-DnaA interaction. The corresponding residues are evolutionarily conserved and are required for unwinding in the initial complexes of Thermotoga maritima, an ancient hyperthermophile. Therefore, our findings suggest a novel and common mechanism for ATP-DnaA-dependent activation of initial complexes.

  10. Observing the Circumstellar Environment of the Eruptive FUor/EXor Protostar V1647 Ori with ALMA

    NASA Astrophysics Data System (ADS)

    Principe, David; Cieza, Lucas A.; Zhu, Zhaohuan; Tobin, John J.; Prieto, Jose Luis

    2016-01-01

    Fu Ori (FUor) and EXor objects represent a short-lived stage of protostellar evolution characterized by intense mass accretion events which cause extreme variability in the form of outbursts. While it is well demonstrated that these objects exhibit sudden outbursts (ΔV~2-6), the mechanism causing such variability is not well understood. High spatial and spectral resolution observations of the circumstellar environment of these objects are essential to distinguish between different outbursting mechanisms. We present ALMA observations of the FUor/EXor object V1647 Ori as part of an ALMA campaign, which has observed a combined eight FUor and EXor type objects. Deeply embedded in the dark cloud LDN 1630 (L1630), V1647 Ori is one of a few FUor/EXor objects to have been extensively studied at multiple wavelengths before, during and after an outburst. We present preliminary results derived from ALMA 12CO, 13CO, C18O and continuum observations of the circumstellar environment of V1647 Ori. By measuring gas/dust masses and gas kinematics of the circumstellar disk, we investigate the potential mechanisms producing variability in these eruptive protostars during an essential, yet rarely observed, stage of pre-main sequence stellar evolution.

  11. 42 CFR 93.217 - Office of Research Integrity or ORI.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Office of Research Integrity or ORI. 93.217 Section 93.217 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH...

  12. OrysPSSP: a comparative Platform for Small Secreted Proteins from rice and other plants

    PubMed Central

    Pan, Bohu; Sheng, Jia; Sun, Weining; Zhao, Yinhong; Hao, Pei; Li, Xuan

    2013-01-01

    Plants have large diverse families of small secreted proteins (SSPs) that play critical roles in the processes of development, differentiation, defense, flowering, stress response, symbiosis, etc. Oryza sativa is one of the major crops worldwide and an excellent model for monocotyledonous plants. However, there had not been any effort to systematically analyze rice SSPs. Here, we constructed a comparative platform, OrysPSSP (http://www.genoportal.org/PSSP/index.do), involving >100 000 SSPs from rice and 25 plant species. OrysPSSP is composed of a core SSP database and a dynamic web interface that integrates a variety of user tools and resources. The current release (v0530) of core SSP database contains a total of 101 048 predicted SSPs, which were generated through a rigid computation/curation pipeline. The web interface consists of eight different modules, providing users with rich resources/functions, e.g. browsing SSP by chromosome, searching and filtering SSP, validating SSP with omics data, comparing SSP among multiple species and querying core SSP database with BLAST. Some cases of application are discussed to demonstrate the utility of OrysPSSP. OrysPSSP serves as a comprehensive resource to explore SSP on the genome scale and across the phylogeny of plant species. PMID:23203890

  13. FU Ori-type outburst of 2MASS J06593158-0405277

    NASA Astrophysics Data System (ADS)

    Maehara, Hiroyuki; Kojima, Tadashi; Fujii, Mitsugu

    2014-11-01

    We report the discovery of an FU Ori-type outburst of 2MASS J06593158-0405277. The outburst was discovered by T. Kojima from the survey image obtained with a 85mm f/2.8 lens and Canon EOS 60D DSLR camera on 2014-11-03.821 UT at mag 11.0.

  14. Indigenous Māori perspectives on urban transport patterns linked to health and wellbeing.

    PubMed

    Raerino Ngāti Awa Te Arawa, K; Macmillan, Alex K; Jones Ngāti Kahungunu, Rhys G

    2013-09-01

    There is a growing body of research linking urban transport systems to inequities in health. However, there is a lack of research providing evidence of the effect of transport systems on indigenous family wellbeing. We examined the connections between urban transport and the health and wellbeing of Māori, the indigenous people of New Zealand. We provide an indigenous exploration of current urban transport systems, with a particular focus on the impacts of car dependence and the need for culturally relevant travel. We interviewed nineteen Māori participants utilising qualitative research techniques underpinned by an indigenous research methodology (Kaupapa Māori). The data highlighted the importance of accessing cultural activities and sites relevant to 'being Māori', and issues with affordability and safety of public transport. Understanding the relationship between indigenous wellbeing and transport systems that goes further than limited discourses of inequity is essential to improving transport for indigenous wellbeing. Providing an indigenous voice in transport decision-making will make it more likely that indigenous health and wellbeing is prioritised in transport planning.

  15. Otariodibacter oris and Bisgaardia genomospecies 1 isolated from infections in pinnipeds.

    PubMed

    Hansen, Mie Johanne; Bertelsen, Mads Frost; Delaney, Martha Ann; Fravel, Vanessa Ashley; Gulland, Frances; Bojesen, Anders Miki

    2013-07-01

    We document the first associations of two recently described species of Pasteurellaceae bacteria with lesions in wild pinnipeds in rehabilitation. Samples were collected from nine lesions in four California sea lions (Zalophus californianus) and two Pacific harbor seals (Phoca vitulina) during necropsy or admission examinations at a rehabilitation facility in northern California. Seven Pasteurellaceae isolates were identified using phenotypic tests and partial rpoB gene sequencing. Six strains of Otariodibacter oris were isolated from California sea lions. Otariodibacter oris was isolated in pure culture from four abscesses, an affected lymph node, and a bone lesion consistent with osteomyelitis. Otariodibacter oris was also cultured with Arcanobacterium phocae and β-hemolytic streptococci. A pure culture of Bisgaardia genomospecies 1 was obtained from an abscess in a harbor seal. This is the first time, to our knowledge, that O. oris has been associated with infection. Isolation of these bacteria in pure culture from abscesses and osteomyelitis strongly indicates a pathogenic potential of this organism. Likewise, the isolation of Bisgaardia genomospecies 1 in pure culture from an abscess in a harbor seal implies causality.

  16. 42 CFR 93.403 - ORI review of research misconduct proceedings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false ORI review of research misconduct proceedings. 93.403 Section 93.403 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH...

  17. 42 CFR 93.403 - ORI review of research misconduct proceedings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false ORI review of research misconduct proceedings. 93.403 Section 93.403 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH...

  18. 42 CFR 93.403 - ORI review of research misconduct proceedings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false ORI review of research misconduct proceedings. 93.403 Section 93.403 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH...

  19. 42 CFR 93.403 - ORI review of research misconduct proceedings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false ORI review of research misconduct proceedings. 93.403 Section 93.403 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH...

  20. Narratives and traits in personality development among New Zealand Māori, Chinese, and European adolescents.

    PubMed

    Reese, Elaine; Chen, Yan; McAnally, Helena M; Myftari, Ella; Neha, Tia; Wang, Qi; Jack, Fiona

    2014-07-01

    Narrative and trait levels of personality were assessed in a sample of 268 adolescents from age 12 to 21 from New Zealand Māori, Chinese, and European cultures. Adolescents narrated three critical events and completed a Big Five personality inventory. Each narrative was coded for causal and thematic coherence. NZ Chinese adolescents reported lower levels of extraversion, agreeableness, conscientiousness, and openness, and higher levels of neuroticism, than NZ Māori or European adolescents. Cultural differences were also evident in narrative coherence. Adolescents in all three groups demonstrated age-related increases in thematic coherence, but only NZ European adolescents demonstrated the expected age-related increases in causal coherence. Narrative identity and traits were distinct aspects of personality for younger adolescents, but were linked for middle and older adolescents. These findings support the importance of both narrative identity and traits in understanding personality development in adolescents across cultures.

  1. L'effet Casimir : théorie et expériences

    NASA Astrophysics Data System (ADS)

    Lambrecht, A.; Genet, C.; Intravaia, F.; Reynaud, S.

    2004-11-01

    L'existence de fluctuations irréductibles de champ dans le vide est une prédiction importante de la théorie quantique. Ces fluctuations ont de nombreuses conséquences observables comme l'effet Casimir, qui est maintenant mesuré avec une bonne précision et un bon accord avec la théorie, pourvu que celle-ci tienne compte des différences entre les expériences rélles et la situation idéale considérée par H.G.B. Casimir. Nous présenterons quelqu'unes des expériences récentes et discuterons les principales corrections à la force de Casimir liées à la situation expérimentale.

  2. MOST OBSERVATIONS OF {sigma} Ori E: CHALLENGING THE CENTRIFUGAL BREAKOUT NARRATIVE

    SciTech Connect

    Townsend, R. H. D.; Rivinius, Th.; Rowe, J. F.; Moffat, A. F. J.; Matthews, J. M.; Kallinger, T.; Kuschnig, R.; Bohlender, D.; Neiner, C.; Telting, J. H.; Guenther, D. B.; Rucinski, S. M.; Sasselov, D.; Weiss, W. W.

    2013-05-20

    We present results from three weeks' photometric monitoring of the magnetic helium-strong star {sigma} Ori E using the Microvariability and Oscillations of Stars microsatellite. The star's light curve is dominated by twice-per-rotation eclipse-like dimmings arising when magnetospheric clouds transit across and occult the stellar disk. However, no evidence is found for any abrupt centrifugal breakout of plasma from the magnetosphere, either in the residual flux or in the depths of the light minima. Motivated by this finding we compare the observationally inferred magnetospheric mass against that predicted by a breakout analysis. The large discrepancy between the values leads us to argue that centrifugal breakout does not play a significant role in establishing the magnetospheric mass budget of {sigma} Ori E.

  3. My Home is My Marae: Kaupapa Māori evaluation of an approach to injury prevention

    PubMed Central

    Hayward, Brooke; Lyndon, Mataroria; Villa, Luis; Madell, Dominic; Elliot-Hohepa, Andrea; Le Comte, Lyndsay

    2017-01-01

    Objective The objective of this study was to evaluate the New Zealand Accident Compensation Corporation's (ACC) ‘My Home is My Marae’ approach to injury prevention for whānau (families). Setting Over an 18 month period from November 2013 to June 2014, 14 ‘My Home is My Marae’ trials were conducted across the South Auckland and Far North regions of New Zealand. ACC engaged with local Māori providers of healthcare, education and social services to deliver the home safety intervention. Participants Participants of this evaluation were a purposive sample of 14 staff from six provider organisations in South Auckland and the Far North regions of New Zealand. Methods Kaupapa Māori theory-based evaluation and appreciative inquiry methodologies underpinned the evaluation. Interview participants led discussions about strengths and weaknesses of the approach, and partnerships with ACC and other organisations. The evaluation was also supported by pre-existing information available in project documentation, and quantitative data collected by Māori providers. Results Five key critical success factors of ‘My Home is My Marae’ were found from interviews: mana tangata (reputation, respect and credibility); manākitanga (showing care for people); kānohi-ki-te-kānohi (face-to-face approach); capacity building for kaimahi, whānau and providers and ‘low or no cost’ solutions to hazards in the home. Data collected for the Far North area showed that 76% of the hazards identified could be resolved through ‘low or no cost’ solutions. Unfortunately, similar data were not available for South Auckland. Conclusions Injury prevention or health promotion approaches that seek to engage with whānau and/or Māori communities would benefit from applying critical success factors of ‘My Home is My Marae’. PMID:28320792

  4. Apsidal motion of two eclipsing binaries: V796 Cyg and V2783 Ori

    NASA Astrophysics Data System (ADS)

    Bulut, A.; Bulut, I.; ćiçek, C.; Erdem, A.

    2017-02-01

    In this study, the orbital period variations of two eclipsing binary systems showing apsidal motion were studied. Their O - C diagrams were analysed using all reliable eclipse timings and the elements of apsidal motion of two systems were improved. We found periods of apsidal motion of V796 Cyg and V2783 Ori to be 32.7 ± 0.2 years and 415 ± 50 years, respectively.

  5. Fabrication, characterization, and heuristic trade space exploration of magnetically actuated Miura-Ori origami structures

    NASA Astrophysics Data System (ADS)

    Cowan, Brett; von Lockette, Paris R.

    2017-04-01

    The authors develop magnetically actuated Miura-Ori structures through observation, experiment, and computation using an initially heuristic strategy followed by trade space visualization and optimization. The work is novel, especially within origami engineering, in that beyond final target shape approximation, Miura-Ori structures in this work are additionally evaluated for the shape approximation while folding and for their efficient use of their embedded actuators. The structures consisted of neodymium magnets placed on the panels of silicone elastomer substrates cast in the Miura-Ori folding pattern. Initially four configurations, arrangements of magnets on the panels, were selected based on heuristic arguments that (1) maximized the amount of magnetic torque applied to the creases and (2) reduced the number of magnets needed to affect all creases in the pattern. The results of experimental and computational performance metrics were used in a weighted sum model to predict the optimum configuration, which was then fabricated and experimentally characterized for comparison to the initial prototypes. As expected, optimization of magnet placement and orientation was effective at increasing the degree of theoretical useful work. Somewhat unexpectedly, however, trade space results showed that even after optimization, the configuration with the most number of magnets was least effective, per magnet, at directing its actuation to the structure’s creases. Overall, though the winning configuration experimentally outperformed its initial, non-optimal counterparts, results showed that the choice of optimum configuration was heavily dependent on the weighting factors. These results highlight both the ability of the Miura-Ori to be actuated with external magnetic stimuli, the effectiveness of a heuristic design approach that focuses on the actuation mechanism, and the need to address path-dependent metrics in assessing performance in origami folding structures.

  6. Reducing smoking in pregnancy among Māori women: "aunties" perceptions and willingness to help.

    PubMed

    van Esdonk, Tineke; Glover, Marewa; Kira, Anette; Wagemakers, Annemarie

    2014-12-01

    ori (the indigenous people of New Zealand) women have high rates of smoking during pregnancy and 42 % register with a lead maternity carer (LMC) after their first trimester, delaying receipt of cessation support. We used a participatory approach with Māori community health workers ("Aunties") to determine their willingness and perceived ability to find pregnant Māori smokers early in pregnancy and to provide cessation support. Three meetings were held in three different regions in New Zealand. The aunties believed they could find pregnant women in first trimester who were still smoking by using their networks, the 'kumara-vine' (sweet potato vine), tohu (signs/omens), their instinct and by looking for women in the age range most likely to get pregnant. The aunties were willing to provide cessation and other support but they said they would do it in a "Māori way" which depended on formed relationships and recognised roles within families. The aunties' believed that their own past experiences with pregnancy and/or smoking would be advantageous when providing support. Aunties' knowledge about existing proven cessation methods and services and knowledge about how to register with a LMC ranged from knowing very little to having years of experience working in the field. They were all supportive of receiving up-to-date information on how best to support pregnant women to stop smoking. Aunties in communities believe that they could find pregnant women who smoke and they are willing to help deliver cessation support. Our ongoing research will test the effectiveness of such an approach.

  7. X-Ray Production by V1647 Ori During Optical Outbursts

    NASA Technical Reports Server (NTRS)

    Teets, William; Weintraub, David; Grosso, Nicolas; Principe, David; Kastner, Joel; Hamaguchi, Kenji; Richmond, Michael

    2011-01-01

    The pre-main-sequence (PMS) star V1647 Ori has recently undergone two optical/near-infrared (OIR) outbursts that are associated with dramatic enhancements in the stellar accretion rate. Our intensive X-ray monitoring of this object affords the opportunity to investigate whether and how the intense X-ray emission is related to PMS accretion activity. Our analysis of all 14 Chandra X-Ray Observatory observations of V1647 Ori demonstrates that variations in the X-ray luminosity of V1647 Ori are correlated with similar changes in the OIR brightness of this source during both (2003-2005 and 2008) eruptions, strongly supporting the hypothesis that accretion is the primary generation mechanism for the X-ray outbursts. Furthermore, the Chandra monitoring demonstrates that the X-ray spectral properties of the second eruption were strikingly similar to those of the 2003 eruption. We find that X-ray spectra obtained immediately following the second outburstduring which V1647 Ori exhibited high X-ray luminosities, high hardness ratios, and strong X-ray variabilityare well modeled as a heavily absorbed (N H 4 1022cm2), single-component plasma with characteristic temperatures (kT X 2-6keV) that are consistently too high to be generated via accretion shocks but are in the range expected for plasma heated by magnetic reconnection events. We also find that the X-ray absorbing column has not changed significantly throughout the observing campaign. Since the OIR and X-ray changes are correlated, we hypothesize that these reconnection events either occur in the accretion stream connecting the circumstellar disk to the star or in accretion-enhanced protostellar coronal activity.

  8. Muscle Cramps

    MedlinePlus

    Muscle cramps are sudden, involuntary contractions or spasms in one or more of your muscles. They often occur after exercise or at night, ... to several minutes. It is a very common muscle problem. Muscle cramps can be caused by nerves ...

  9. Muscle Disorders

    MedlinePlus

    Your muscles help you move and help your body work. Different types of muscles have different jobs. There are many problems that can affect muscles. Muscle disorders can cause weakness, pain or even ...

  10. Your Muscles

    MedlinePlus

    ... of the heart because it controls the heartbeat. Skeletal Muscle Now, let's talk about the kind of muscle ... soccer ball into the goal. These are your skeletal muscles — sometimes called striated (say: STRY-ay-tud) muscle ...

  11. Use of the angularis oris cutaneous flap for repair of a rostral mandibular skin defect in a cat.

    PubMed

    Bradford, M; Degner, D A; Bhandal, J

    2011-01-01

    The angularis oris axial pattern flap is based on the blood supply of the angularis oris artery and vein. While the use of this flap for repair of canine facial wounds is well documented, this technique has not been reported in the cat. This case report presents the reconstruction of a large ventral chin and rostral lip wound with the use of this flap. Complete survival of this flap was observed in this patient.

  12. THE STRUCTURE AND KINEMATICS OF THE ENVELOPE AROUND U ORI FROM IOTA OBSERVATIONS

    SciTech Connect

    Pluzhnik, Eugene A.; Ragland, Sam; Le Coroller, Herve; Danchi, William C.; Traub, Wesley A.

    2009-07-20

    Many of the Mira stars observed with adequate spatial resolution show detectable asymmetry. This asymmetry can be caused by an asymmetric stellar photosphere and/or asymmetric envelope around the star and can be the origin of asymmetries in the subsequent planetary nebula. In this paper, we present the results of long baseline interferometric observations of the Mira-type star U Ori at 1.51 (H{sub 2}O band), 1.64 (pseudocontinuum), and 1.78 (H{sub 2}O band) {mu}m in 2005. We performed model-independent image reconstruction of the envelope around the star using measured visibilities and closure phases. The images show asymmetric structure of the U Ori envelope that is similar to the structure of 22 GHz H{sub 2}O masers obtained by Vlemmings et al. in 2003. Further comparison of near infrared images with available radio maps gives some evidence for differential rotation of the envelope with rotational velocities varying between 3 and 5 km s{sup -1}. Finally, we discuss the geometric and kinematic structure of the U Ori envelope based on a model of an almost face-on expanding and rotating disk around the star.

  13. A Comparison of Pacific, Māori, and European Violent Youth Offenders in New Zealand.

    PubMed

    Ioane, Julia; Lambie, Ian; Percival, Teuila

    2016-05-01

    Pacific Island and Māori youth are disproportionately overrepresented in Aotearoa/New Zealand in violent offending. To date, research has not examined Pacific Island violent youth offenders in comparison with other ethnic populations. This study compared Pacific Island violent youth offenders with Māori and European violent youth offenders to determine whether similarities or differences existed in their offending, social, and demographic characteristics. Findings showed that Pacific Island violent youth offenders, in comparison with Māori and European violent youth offenders, were more likely to have grown up in the lowest socioeconomic deprivation areas in New Zealand, were more likely to be older when they first started offending, and their first offence was more likely to be of a serious, violent nature. Family violence was present among all three ethnic groups highlighting the ongoing importance of intervention in this area. The findings of the current study are likely to have implications for government department policy makers, along with program providers and practitioners. Recommendations are made regarding clinical implications and future research on this population.

  14. Multi-Wavelength Study of the 2008-2009 Outburst of V1647 Ori

    NASA Astrophysics Data System (ADS)

    García-Alvarez, D.; Wright, N. J.; Drake, J. J.; Abraham, P.; Anandarao, B. G.; Kashyap, V.; Kospal, A.; Kun, M.; Marengo, M.; Moor, A.; Peneva, S.; Semkov, E.; Venkat, V.; Sanz-Forcada, J.

    2011-12-01

    V1647 Ori is a young eruptive variable star, illuminating a reflection nebula (McNeil's Nebula). It underwent an outburst in 2003 before fading back to its pre-outburst brightness in 2006. In 2008, V1647 Ori underwent a new outburst. The observed properties of the 2003-2006 event are different in several respects from both the EXor and FUor type outbursts, and suggest that this star might represent a new class of eruptive young stars, younger and more deeply embedded than EXors, and exhibiting variations on shorter time scales than FUors. In outburst, the star lights up the otherwise invisible McNeil's nebular -- a conical cloud likely accumulated from previous outbursts. We present follow-up photometric as well as optical and near-IR spectroscopy of the nebula obtainted during the 2008-2009 outburst. We will also present results from contemporaneous X-ray observations. These multi-wavelength observations of V1647 Ori, obtained at this key early stage of the outburst, provide a snapshot of the "lighting up" of the nebula, probe its evolution through the event, and enable comparison with the 2003-2006 outburst.

  15. Narratives of four Māori ex-inmates about their experiences and perspectives of rehabilitation programmes.

    PubMed

    Nakhid, Camille; Shorter, Lily Tairiri

    2014-06-01

    ori are overrepresented in the criminal justice system in Aotearoa New Zealand. Māori offenders comprise 53% of those serving custodial sentences and 48% serving community-based sentences. The majority of Māori offenders reoffended within 2 years of serving their sentence. A number of programmes aimed at reducing recidivism among Māori have been implemented, and there is considerable debate around the effectiveness of these programmes. This qualitative study focuses on the narratives of four Māori male ex-inmates about their reoffending and their experiences of the rehabilitation programmes during their incarceration. Using a narrative approach, the study sought to hear the shared stories from the men and to determine what they believe would have reduced their reoffending. The stories revealed that a lack of financial resources and gang connections influenced reoffending; the value of prison rehabilitation programmes varied depending on their appropriateness to the inmate and to their intended outcomes; and healing programmes incorporating kaupapa Māori principles and practices assisted the participants in understanding their cultural heritage and communicating with society in more acceptable ways.

  16. Jaw adductor muscles across lepidosaurs: a reappraisal.

    PubMed

    Daza, Juan Diego; Diogo, Rui; Johnston, Peter; Abdala, Virginia

    2011-10-01

    The exact homologies of tetrapod jaw muscles remain unresolved, and this provides a barrier for phylogenetic analysis and tracing character evolution. Here, lepidosaur jaw muscles are surveyed using direct examination of species from 23 families and published descriptions of species from 10 families. A revised nomenclature is applied according to proposed homologies with Latimeria. Among lepidosaurs, variation was found in many aspects of jaw muscle anatomy. The superficial layers mm. levator and retractor anguli oris (LAO and RAO) are present in Sphenodon but not all squamates. The external jaw adductor muscles universally present in lepidosaurs are homologous with the main adductor muscle, A2, of Latimeria and include four layers: superficialis (A2-SUP), medialis (A2-M), profundus (A2-PRO), and posterior (A2-PVM). The A2-SUP appears divided in Agamidae, Gekkota, Xantusiidae, and Varanidae. The A2-M is layered lateromedial in lizards but anteroposterior in snakes. The names pseudotemporalis (PS) and pterygomandibularis (PTM) are recommended for subdivisions of the internal adductors of reptiles and amphibians, because the homology of this muscle with the A3' and A3 ″ of Latimeria remains inconclusive. The intramandibularis of lepidosaurs and Latimeria (A-ω) are homologous. The distribution of six jaw muscle characters was found to plot more parsimoniously on phylogenies based on morphological rather than and molecular data. Character mapping indicates that Squamata presents reduction in the divisions of the A2-M, Scincoidea presents reduction or loss of LAO, and two apomorphic features are found for the Gekkota.

  17. 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...

  18. HH 222: A GIANT HERBIG-HARO FLOW FROM THE QUADRUPLE SYSTEM V380 ORI

    SciTech Connect

    Reipurth, Bo; Aspin, Colin; Connelley, M. S.; Bally, John; Geballe, T. R.; Kraus, Stefan; Appenzeller, Immo; Burgasser, Adam E-mail: caa@ifa.hawaii.edu E-mail: John.Bally@colorado.edu E-mail: stefan.kraus@cfa.harvard.edu E-mail: aburgasser@ucsd.edu

    2013-11-01

    HH 222 is a giant shocked region in the L1641 cloud, and is popularly known as the Orion Streamers or ''the waterfall'' on account of its unusual structure. At the center of these streamers are two infrared sources coincident with a nonthermal radio jet aligned along the principal streamer. The unique morphology of HH 222 has long been associated with this radio jet. However, new infrared images show that the two sources are distant elliptical galaxies, indicating that the radio jet is merely an improbable line-of-sight coincidence. Accurate proper motion measurements of HH 222 reveal that the shock structure is a giant bow shock moving directly away from the well-known, very young, Herbig Be star V380 Ori. The already known Herbig-Haro object HH 35 forms part of this flow. A new Herbig-Haro object, HH 1041, is found precisely in the opposite direction of HH 222 and is likely to form part of a counterflow. The total projected extent of this HH complex is 5.3 pc, making it among the largest HH flows known. A second outflow episode from V380 Ori is identified as a pair of HH objects, HH 1031 to the northwest and the already known HH 130 to the southeast, along an axis that deviates from that of HH 222/HH 1041 by only 3.°7. V380 Ori is a hierarchical quadruple system, including a faint companion of spectral type M5 or M6, which at an age of ∼1 Myr corresponds to an object straddling the stellar-to-brown dwarf boundary. We suggest that the HH 222 giant bow shock is a direct result of the dynamical interactions that led to the conversion from an initial non-hierarchical multiple system into a hierarchical configuration. This event occurred no more than 28,000 yr ago, as derived from the proper motions of the HH 222 giant bow shock.

  19. HH 222: A Giant Herbig-Haro Flow from the Quadruple System V380 Ori

    NASA Astrophysics Data System (ADS)

    Reipurth, Bo; Bally, John; Aspin, Colin; Connelley, M. S.; Geballe, T. R.; Kraus, Stefan; Appenzeller, Immo; Burgasser, Adam

    2013-11-01

    HH 222 is a giant shocked region in the L1641 cloud, and is popularly known as the Orion Streamers or "the waterfall" on account of its unusual structure. At the center of these streamers are two infrared sources coincident with a nonthermal radio jet aligned along the principal streamer. The unique morphology of HH 222 has long been associated with this radio jet. However, new infrared images show that the two sources are distant elliptical galaxies, indicating that the radio jet is merely an improbable line-of-sight coincidence. Accurate proper motion measurements of HH 222 reveal that the shock structure is a giant bow shock moving directly away from the well-known, very young, Herbig Be star V380 Ori. The already known Herbig-Haro object HH 35 forms part of this flow. A new Herbig-Haro object, HH 1041, is found precisely in the opposite direction of HH 222 and is likely to form part of a counterflow. The total projected extent of this HH complex is 5.3 pc, making it among the largest HH flows known. A second outflow episode from V380 Ori is identified as a pair of HH objects, HH 1031 to the northwest and the already known HH 130 to the southeast, along an axis that deviates from that of HH 222/HH 1041 by only 3.°7. V380 Ori is a hierarchical quadruple system, including a faint companion of spectral type M5 or M6, which at an age of ~1 Myr corresponds to an object straddling the stellar-to-brown dwarf boundary. We suggest that the HH 222 giant bow shock is a direct result of the dynamical interactions that led to the conversion from an initial non-hierarchical multiple system into a hierarchical configuration. This event occurred no more than 28,000 yr ago, as derived from the proper motions of the HH 222 giant bow shock.

  20. The Design and Relevance of a Computerized Gamified Depression Therapy Program for Indigenous Māori Adolescents

    PubMed Central

    Fleming, Theresa; Lucassen, Mathijs; Stasiak, Karolina

    2015-01-01

    Background Depression is a major health issue among Māori indigenous adolescents, yet there has been little investigation into the relevance or effectiveness of psychological treatments for them. Further, consumer views are critical for engagement and adherence to therapy. However, there is little research regarding indigenous communities’ opinions about psychological interventions for depression. Objective The objective of this study was to conduct semistructured interviews with Māori (indigenous New Zealand) young people (taitamariki) and their families to find out their opinions of a prototype computerized cognitive behavioral therapy (cCBT) program called Smart, Positive, Active, Realistic, X-factor thoughts (SPARX), a free online computer game intended to help young persons with mild to moderate depression, feeling down, stress or anxiety. The program will teach them how to resolve their issues on their own using Cognitive Behavioural Therapy as psychotherapeutic approach. Methods There were seven focus groups on the subject of the design and cultural relevance of SPARX that were held, with a total of 26 participants (19 taitamarki, 7 parents/caregivers, all Māori). There were five of the groups that were with whānau (family groups) (n=14), one group was with Māori teenage mothers (n=4), and one group was with taitamariki (n=8). The general inductive approach was used to analyze focus group data. Results SPARX computerized therapy has good face validity and is seen as potentially effective and appealing for Māori people. Cultural relevance was viewed as being important for the engagement of Māori young people with SPARX. Whānau are important for young peoples’ well-being. Participants generated ideas for improving SPARX for Māori and for the inclusion of whānau in its delivery. Conclusions SPARX computerized therapy had good face validity for indigenous young people and families. In general, Māori participants were positive about the SPARX

  1. HU, the major histone-like protein of E. coli, modulates the binding of IHF to oriC.

    PubMed Central

    Bonnefoy, E; Rouvière-Yaniv, J

    1992-01-01

    HU is one of the most abundant DNA binding proteins of bacteria. Unlike IHF, integration host factor of Escherichia coli, with which HU shares many properties, including a strong sequence homology and similar predicted structure, HU seems to bind non-specifically to DNA whereas IHF binds to specific sites. In this work we compare the binding characteristics of HU and IHF to a DNA fragment containing the minimal origin of replication of E. coli (oriC) and we analyse the effect of HU on the binding capacity of IHF to this oriC fragment. We show that HU interacts randomly and non-specifically with oriC as opposed to the specific binding of IHF to this same DNA sequence. In addition, we show that HU can modulate the binding of IHF to its specific oriC site. Depending on the relative concentrations of HU and IHF, HU is able either to activate or to inhibit the binding of IHF to oriC. Images PMID:1425583

  2. Muscle Deoxygenation Causes Muscle Fatigue

    NASA Technical Reports Server (NTRS)

    Murthy, G.; Hargens, A. R.; Lehman, S.; Rempel, D.

    1999-01-01

    Muscle fatigue is a common musculoskeletal disorder in the work place, and may be a harbinger for more disabling cumulative trauma disorders. Although the cause of fatigue is multifactorial, reduced blood flow and muscle oxygenation may be the primary factor in causing muscle fatigue during low intensity muscle exertion. Muscle fatigue is defined as a reduction in muscle force production, and also occurs among astronauts who are subjected to postural constraints while performing lengthy, repetitive tasks. The objectives of this research are to: 1) develop an objective tool to study the role of decreased muscle oxygenation on muscle force production, and 2) to evaluate muscle fatigue during prolonged glovebox work.

  3. Muscle disorder

    MedlinePlus

    Myopathic changes; Myopathy; Muscle problem ... Blood tests sometimes show abnormally high muscle enzymes. If a muscle disorder might also affect other family members, genetic testing may be done. When someone has symptoms and signs ...

  4. Muscle aches

    MedlinePlus

    ... common cause of muscle aches and pain is fibromyalgia , a condition that causes tenderness in your muscles ... imbalance, such as too little potassium or calcium Fibromyalgia Infections, including the flu, Lyme disease , malaria , muscle ...

  5. Redesigning the architecture of policy-making: Engaging with Māori on nanotechnology in New Zealand.

    PubMed

    Munshi, Debashish; Kurian, Priya A; Morrison, Talei; Morrison, Sandra L

    2016-04-01

    Although there is an extensive literature on public engagement on the use of new and emerging technologies such as nanotechnology, there is little evidence of the participation of marginalised indigenous communities in processes of such engagement. How do particular cultural values and worldviews shape the perceptions of new technologies among such indigenous peoples? This article addresses this question through an analysis of the deliberations of an indigenous Māori citizens' panel on nanotechnology in Aotearoa New Zealand. An active process of public engagement with the nation's Māori stakeholders, and their conversations with nanotechnology experts, sustainability activists and Māori researchers, helps map an alternative, culture-based architecture of public engagement on policies around new technologies. The analysis is grounded in a concept of active citizenship that we term 'sustainable citizenship'.

  6. Couples Work in Cultural Context: Te Ao Māori and Poststucturalist Practices Informing Counselor Training in Aotearoa New Zealand.

    PubMed

    Connor, Helene; Gremillion, Helen; Meima, Yolanda

    2016-06-01

    This article outlines key themes that appear in the teaching of poststructuralist ideas and practices for couples counseling within the Postgraduate Diploma in Counseling Program at Unitec Institute of Technology in Auckland, New Zealand, and it explores the congruence of this pedagogical approach with Māori (indigenous) understandings of relationality, collaboration, and partnership. The diploma program's curriculum includes narrative therapy and relational language-making. Themes explored in this article include: understanding (heterosexual) couple relationships as contextualized entities, deconstructing dominant discourses of coupledom, and the positioning of counselors/teachers as nonexpert. Taking each theme in turn, the authors, one of them Māori and two Pākehā (European), articulate points of alignment with Māori cultural concepts and practices.

  7. OryR is a LuxR-family protein involved in interkingdom signaling between pathogenic Xanthomonas oryzae pv. oryzae and rice.

    PubMed

    Ferluga, Sara; Venturi, Vittorio

    2009-02-01

    Xanthomonas oryzae pv. oryzae, the causal agent of bacterial leaf blight in rice, contains a regulator that is encoded in the genome, designated OryR, which belongs to the N-acyl homoserine lactone (AHL)-dependent quorum-sensing LuxR subfamily of proteins. However, we previously reported that X. oryzae pv. oryzae does not make AHLs and does not possess a LuxI-family AHL synthase and that the OryR protein is solubilized by a compound present in rice. In this study we obtained further evidence that OryR interacts with a rice signal molecule (RSM) and that the OryR concentration increases when rice is infected with X. oryzae pv. oryzae. We also describe three OryR target promoters which are regulated differently: (i) the neighboring proline iminopeptidase (pip) virulence gene, which is positively regulated by OryR in the presence of the RSM; (ii) the oryR promoter, which is negatively autoregulated independent of the RSM; and (iii) the 1,4-beta-cellobiosidase cbsA gene, which is positively regulated by OryR independent of the RSM. We also found that the RSM for OryR is small, is not related to AHLs, and is not able to activate the broad-range AHL biosensor Agrobacterium tumefaciens NT1(pZLQR). Furthermore, OryR does not regulate production of the quorum-sensing diffusible signal factor present in the genus Xanthomonas. Therefore, OryR has unique features and is an important regulator involved in interkingdom communication between the host and the pathogen.

  8. A qualitative analysis of Māori and Pacific smokers' views on informed choice and smoking

    PubMed Central

    Gifford, Heather; Tautolo, El-Shadan; Erick, Stephanie; Hoek, Janet; Gray, Rebecca; Edwards, Richard

    2016-01-01

    Objectives Tobacco companies frame smoking as an informed choice, a strategy that holds individuals responsible for harms they incur. Few studies have tested this argument, and even fewer have examined how informed indigenous smokers or those from minority ethnicities are when they start smoking. We explored how young adult Māori and Pacific smokers interpreted ‘informed choice’ in relation to smoking. Participants Using recruitment via advertising, existing networks and word of mouth, we recruited and undertook qualitative in-depth interviews with 20 Māori and Pacific young adults aged 18–26 years who smoked. Analyses Data were analysed using an informed-choice framework developed by Chapman and Liberman. We used a thematic analysis approach to identify themes that extended this framework. Results Few participants considered themselves well informed and none met more than the framework's initial two criteria. Most reflected on their unthinking uptake and subsequent addiction, and identified environmental factors that had facilitated uptake. Nonetheless, despite this context, most agreed that they had made an informed choice to smoke. Conclusions The discrepancy between participants' reported knowledge and understanding of smoking's risks, and their assessment of smoking as an informed choice, reflects their view of smoking as a symbol of adulthood. Policies that make tobacco more difficult to use in social settings could help change social norms around smoking and the ease with which initiation and addiction currently occur. PMID:27188813

  9. Metallurgy of Miura-ori: lattice theory for inhomogeneous deformations of origami tessellations

    NASA Astrophysics Data System (ADS)

    Evans, Arthur; Silverberg, Jesse; McLeod, Lauren; Cohen, Itai; Santangelo, Christian

    2014-03-01

    In nature, as well as in art, one often encounters thin materials that have been deformed by their environment or their creator into complex folded states; examples include the folds of the endoplasmic reticulum, the villi in the intestinal tract, and tessellated patterns in the ancient Japanese art of origami. One (engineering) advantage of creating a folded structure is that the geometric constraints associated with creasing imbues the construction with exotic mechanical properties, such as generating a material with a negative Poisson's ratio. Materials exhibiting novel behavior of this type, arising from the special properties of the unit cell, are generally classified as metamaterials. In this talk I consider a mechanical metamaterial known as Miura-ori, an origami tessellation pattern that displays soft modes and crystallographic defects not accounted for by a purely geometric theory of an infinitely thin material. I will discuss a method for deriving how inhomogeneous deformations arise from bending within Miura-ori, and show that this leads to a natural coherence length over which the inhomogeneity decays. Additionally, I will show how the modular nature of origami unit cells lends additional richness to the mechanical properties associated with deformation.

  10. DM Ori: A Young Star Occulted by a Disturbance in Its Protoplanetary Disk

    NASA Astrophysics Data System (ADS)

    Rodriguez, Joseph E.; Stassun, Keivan G.; Cargile, Phillip; Shappee, Benjamin J.; Siverd, Robert J.; Pepper, Joshua; Lund, Michael B.; Kochanek, Christopher S.; James, David; Kuhn, Rudolf B.; Beatty, Thomas G.; Gaudi, B. Scott; Weintraub, David A.; Stanek, Krzysztof Z.; Holoien, Thomas W.-S.; Prieto, Jose L.; Feldman, Daniel M.; Espaillat, Catherine C.

    2016-11-01

    In some planet formation theories, protoplanets grow gravitationally within a young star’s protoplanetary disk, a signature of which may be a localized disturbance in the disk’s radial and/or vertical structure. Using time-series photometric observations by the Kilodegree Extremely Little Telescope South project and the All-Sky Automated Survey for SuperNovae, combined with archival observations, we present the discovery of two extended dimming events of the young star, DM Ori. This young system faded by ˜1.5 mag from 2000 March to 2002 August and then again in 2013 January until 2014 September (depth ˜1.7 mag). We constrain the duration of the 2000-2002 dimming to be < 860 days, and the event in 2013-2014 to be < 585 days, separated by ˜12.5 years. A model of the spectral energy distribution indicates a large infrared excess consistent with an extensive circumstellar disk. Using basic kinematic arguments, we propose that DM Ori is likely being periodically occulted by a feature (possibly a warp or perturbation) in its circumstellar disk. In this scenario, the occulting feature is located >6 au from the host star, moving at ˜14.6 km s-1 and is ˜4.9 au in width. This localized structure may indicate a disturbance such as that which may be caused by a protoplanet early in its formation.

  11. Lethality of Sortase Depletion in Actinomyces oris Caused by Excessive Membrane Accumulation of a Surface Glycoprotein

    PubMed Central

    Wu, Chenggang; Huang, I-Hsiu; Chang, Chungyu; Reardon-Robinson, Melissa Elizabeth; Das, Asis; Ton-That, Hung

    2014-01-01

    Sortase, a cysteine-transpeptidase conserved in Gram-positive bacteria, anchors on the cell wall many surface proteins that facilitate bacterial pathogenesis and fitness. Genetic disruption of the housekeeping sortase in several Gram-positive pathogens reported thus far attenuates virulence, but not bacterial growth. Paradoxically, we discovered that depletion of the housekeeping sortase SrtA was lethal for Actinomyces oris; yet, all of its predicted cell wall-anchored protein substrates (AcaA-N) were individually dispensable for cell viability. Using Tn5-transposon mutagenesis to identify factors that upend lethality of srtA deletion, we uncovered a set of genetic suppressors harboring transposon insertions within genes of a locus encoding AcaC and a LytR-CpsA-Psr (LCP)-like protein. AcaC was shown to be highly glycosylated and dependent on LCP for its glycosylation. Upon SrtA depletion, the glycosylated form of AcaC, hereby renamed GspA, was accumulated in the membrane. Overexpression of GspA in a mutant lacking gspA and srtA was lethal; conversely, cells overexpressing a GspA mutant missing a membrane-localization domain were viable. The results reveal a unique glycosylation pathway in A. oris that is coupled to cell wall anchoring catalyzed by sortase SrtA. Significantly, this novel phenomenon of glyco-stress provides convenient cell-based assays for developing a new class of inhibitors against Gram-positive pathogens. PMID:25230351

  12. Benefitting from differences in knowledge, practice and belief: Māori oral traditions and natural hazards science

    NASA Astrophysics Data System (ADS)

    King, D. N.; Goff, J. R.

    2010-09-01

    This paper builds upon earlier work that argued the information and experience contained within the knowledge-practice-belief complex of Mātauranga Māori [Māori knowledge] is a valuable and neglected area of information and understanding about past catastrophic events in Aotearoa/New Zealand (A/NZ). Here we map Māori oral traditions (pūrākau) that relate experience with extreme environmental disturbance (in particular, tsunamis) around the A/NZ coast, compare the findings with geo-archaeological evidence, and discuss the scientific benefits to be gained by considering pūrākau as legitimate perspectives on history. Not surprisingly, there are both differences and complementarities between traditional Māori narratives and the available geo-archaeological evidence on extreme coastal disturbances. The findings presented here raise new and important questions about accepted geographies of tsunami risk, the causes and sources of their generation, as well as reasons for the relative paucity and abundance of information in some regions. Ways in which Mātauranga Taiao [Māori environmental knowledge] and contemporary science can be combined to produce new narratives about extreme environmental disturbance along the A/NZ coastline will require not only acceptance of other ways of knowing but also open engagement with Māori that respects their rights to tell their own histories. These efforts are encouraged to revitalise and ground-truth the interpretation of traditional stories, corroborate and/or question previous scientific deductions, and improve our collective understanding of the recurring impact of tectonic, geologic and meteorological-based events across A/NZ.

  13. Indigenous injury outcomes: life satisfaction among injured Māori in New Zealand three months after injury

    PubMed Central

    2013-01-01

    Background Māori, the indigenous population of New Zealand, experience numerous and consistent health disparities when compared to non-Māori. Injury is no exception, yet there is a paucity of published literature that examines outcomes following a wide variety of injury types and severities for this population. This paper aims to identify pre-injury and injury-related predictors of life satisfaction three months after injury for a group of injured Māori. Methods The Māori sample (n = 566) were all participants in the Prospective Outcomes of Injury Study (POIS). POIS is a longitudinal study of 2856 injured New Zealanders aged 18–64 years who were on an injury entitlement claims’ register with New Zealand’s no-fault compensation insurer. The well-known Te Whare Tapa Whā model of overall health and well-being was used to help inform the selection of post-injury life satisfaction predictor variables. Multivariable analyses were used to examine the relationships between potential predictors and life satisfaction. Results Of the 566 Māori participants, post-injury life satisfaction data was available for 563 (99%) participants. Of these, 71% reported satisfaction with life three months after injury (compared to 93% pre-injury). Those with a higher injury severity score, not satisfied with pre-injury social relationships or poor self-efficacy pre-injury were less likely to be satisfied with life three months after injury. Conclusions The large majority of Māori participants reported being satisfied with life three months after injury; however, nearly a third did not. This suggests that further research investigating outcomes after injury for Māori, and predictors of these, is necessary. Results show that healthcare providers could perhaps put greater effort into working alongside injured Māori who have more severe injuries, report poor self-efficacy and were not satisfied with their pre-injury social relationships to ensure increased likelihood of

  14. Hemifacial spasm and posterior auricular muscle.

    PubMed

    Kiziltan, M; Sahin, R; Uzun, N; Kiziltan, G

    2006-09-01

    We aimed to investigate to which extent posterior auricular muscle (PAM) was affected and whether it contributed to the reflex activity in hemifacial spasm (HFS) patients. 19 HFS patients' spasm activities were recorded from facial muscles. Spasm activity of PAM was recorded synchronously on the symptomatic side in all patients. Lateral spread of blink reflex to orbicularis oris and PAMs were recorded in all but two patients. Botulinum toxin was applied to the PAM with the 14 patients presenting tinnitus, "clicking" or a "ticking" sound on the sane side and other positive auricular symptoms. After treatment, there was symptomatic improvement in 9 of 14 patients. The patients presenting with auricular symptoms and showing spasm activity in their PAMs can be thought as a candidate for botulinum toxin treatment scheme.

  15. The significance of socially-assigned ethnicity for self-identified Māori accessing and engaging with primary healthcare in New Zealand.

    PubMed

    Reid, Jennifer; Cormack, Donna; Crowe, Marie

    2016-03-01

    Despite increased focus in New Zealand on reducing health inequities between Māori and New Zealand European ethnic groups, research on barriers and facilitators to primary healthcare access for Māori remains limited. In particular, there has been little interrogation of the significance of social-assignment of ethnicity for Māori in relation to engagement with predominantly non-Māori primary healthcare services and providers. A qualitative study was undertaken with a subsample (n = 40) of the broader Hauora Manawa Study to examine experiences of accessing and engaging with primary healthcare among adult urban Māori. Thematic analysis of in-depth interviews identified that participants perceived social-assignment as New Zealand European as an efficacious form of capital when interacting with predominantly non-Māori health professionals. Skin colour that was 'white' or was perceived to identify Māori as belonging to the 'dominant' New Zealand European ethnic group was reported as broadly advantageous and protective. In contrast, social-assignment as Māori was seen to be associated with risk of exposure to differential and discriminatory healthcare. Reducing the negative impacts of racialisation in a (neo)colonial society where 'White' cultural capital dominates requires increased recognition of the health-protective advantages of 'White' privilege and concomitant risks associated with socially-assigned categorisation of ethnicity as non-'White'.

  16. Strategies to reduce the use of seclusion with tāngata whai i te ora (Māori mental health service users).

    PubMed

    Wharewera-Mika, Julie PhD; Cooper, Erana PhD; Wiki, Nick Rn; Field, Trudie Rn; Haitana, Jason; Toko, Mike; Edwards, Erika; McKenna, Brian Rn Ba MHSc PhD

    2016-06-01

    ori, the indigenous people of New Zealand, have the highest crude population-based rate of seclusion events reported internationally (McLeod et al. ). This qualitative study explored Māori clinical, cultural and consumer perspectives on potential strategies and initiatives considered likely to facilitate prevention of, and reduction in, the use of seclusion, with tāngata whai i te ora (Māori mental health service users) in mental health inpatient services. A hui (gathering) over 2 days was held with 16 Māori participants with high levels of clinical, cultural and consumer expertise. The gathering was taped and the tapes transcribed. A thematic analysis of the hui data generated three key categories: Te Ao Māori (access to a Māori worldview); Te Ao Hurihuri (transforming practice); and Rangatiratanga (leadership, power, and control). The findings of this study align with the "six core strategies" for best practice to reduce the use of seclusion (Huckshorn ). A comprehensive approach to the reduction of the use of seclusion with tāngata whai i te ora is required, which is clearly based on a Māori model of care and a vision for transformation of practice in mental health inpatient services, which involves Māori leadership.

  17. RepD-mediated recruitment of PcrA helicase at the Staphylococcus aureus pC221 plasmid replication origin, oriD

    PubMed Central

    Machón, C.; Lynch, G. P.; Thomson, N. H.; Scott, D. J.; Thomas, C. D.; Soultanas, P.

    2010-01-01

    Plasmid encoded replication initiation (Rep) proteins recruit host helicases to plasmid replication origins. Previously, we showed that RepD recruits directionally the PcrA helicase to the pC221 oriD, remains associated with it, and increases its processivity during plasmid unwinding. Here we show that RepD forms a complex extending upstream and downstream of the core oriD. Binding of RepD causes remodelling of a region upstream from the core oriD forming a ‘landing pad’ for the PcrA. PcrA is recruited by this extended RepD–DNA complex via an interaction with RepD at this upstream site. PcrA appears to have weak affinity for this region even in the absence of RepD. Upon binding of ADPNP (non-hydrolysable analogue of ATP), by PcrA, a conformational rearrangement of the RepD–PcrA–ATP initiation complex confines it strictly within the boundaries of the core oriD. We conclude that RepD-mediated recruitment of PcrA at oriD is a three step process. First, an extended RepD–oriD complex includes a region upstream from the core oriD; second, the PcrA is recruited to this upstream region and thirdly upon ATP-binding PcrA relocates within the core oriD. PMID:20044350

  18. A particular DNA structure is required for the function of a cis-acting component of the Epstein-Barr virus OriLyt origin of replication.

    PubMed Central

    Portes-Sentis, S; Sergeant, A; Gruffat, H

    1997-01-01

    OriLyt, thecis-acting element of Epstein-Barr virus lytic origin of replication, consists of upstream and downstream components. The upstream component plays a dual role in transcription and replication. The downstream component contains a homopurine-homopyrimidine sequence which forms an H palindrome. We show that the downstream component can adopt a triple helix structure in vitro, that the 5' border of the homopyrimidine sequence is sensitive to P1 nuclease when carried by a supercoiled plasmid and that an oligonucleotide complementary to the homopyrimidine strand is taken up by a plasmid carrying the OriLyt H palindrome. We also show that all mutations which alter the H palindrome impair both oligonucleotide uptake and OriLyt-dependent replication. Interestingly, compensatory mutations which restore an H palindrome also restore oligonucleotide uptake by the mutated plasmids and their OriLyt-dependent replication. Thus, there is a strong correlation between the inability of the OriLyt H palindrome to form a non-B-DNA structure in vitro and impairment of OriLyt-dependent replication. This suggests that the presence of a non-B-DNA structure in the OriLyt downstream component is required for OriLyt-dependent replication. PMID:9060428

  19. ORNL’s ORiGAMI Uses Big Data to Help Solve Age-Old Medical Mysteries in Seconds

    ScienceCinema

    Sukumar, Rangan

    2016-07-12

    ORiGAMI is a tool for discovering and evaluating potentially interesting associations and creating novel hypothesis in medicine. ORiGAMI will help you “connect the dots” across 70 million knowledge nuggets published in 23 million papers in the medical literature.

  20. Interaction of HCMV UL84 with C/EBPalpha transcription factor binding sites within oriLyt is essential for lytic DNA replication.

    PubMed

    Kagele, Dominique; Gao, Yang; Smallenburg, Kate; Pari, Gregory S

    2009-09-15

    Human cytomegalovirus (HCMV) lytic DNA replication is initiated at the cis-acting oriLyt region and requires six core replication proteins along with UL84 and IE2. Although UL84 is thought to be the replication initiator protein, little is known about its interaction with oriLyt. We have now performed chromatin immunoprecipitation assays (ChIP) using antibodies specific to UL84, IE2, UL44, CCAAT/enhancer binding protein (C/EBPalpha) and PCR primers that span the entire oriLyt region to reveal an evaluation of specific protein binding across oriLyt. UL84 interacted with several regions of oriLyt that contain C/EBPalpha transcription factor binding sites. Mutation of either of one of C/EBPalpha (92,526 or 92,535) sites inactivated oriLyt and resulted in the loss of binding of UL84. These data reveal the regions of interaction within oriLyt for several key replication proteins and show that the interaction between UL84 and C/EBPalpha sites within oriLyt is essential for lytic DNA replication.

  1. The Protective Influence of Family Connectedness, Ethnic Identity, and Ethnic Engagement for New Zealand Ma¯ori Adolescents

    ERIC Educational Resources Information Center

    Stuart, Jaimee; Jose, Paul E.

    2014-01-01

    The present study examined the associations among family connectedness, ethnic identity, and ethnic engagement on changes in well-being over time for the understudied population of Ma¯ori (indigenous New Zealand) youth. Data were collected as part of a longitudinal study of youth connectedness in New Zealand using self-report measures at 3…

  2. The protective influence of family connectedness, ethnic identity, and ethnic engagement for New Zealand Ma̅ori adolescents.

    PubMed

    Stuart, Jaimee; Jose, Paul E

    2014-06-01

    The present study examined the associations among family connectedness, ethnic identity, and ethnic engagement on changes in well-being over time for the understudied population of Ma̅ori (indigenous New Zealand) youth. Data were collected as part of a longitudinal study of youth connectedness in New Zealand using self-report measures at 3 measurement occasions separated by 1 year each. Participants in the current study were 431 self-identified Ma̅ori (ages 10-15 years at Time 1). As expected, the variables of family connectedness, ethnic identity, and well-being were all positively related to each other. Results of a latent growth curve model showed that, following normative trends for adolescents of this age, well-being diminished over time for Ma̅ori youth; however, high levels of family connectedness were found to mitigate this general decline in well-being over time. Furthermore, in a longitudinal path analysis, ethnic engagement was found to exert a positive indirect effect on residualized Time 3 well-being through Time 2 ethnic identity. These findings indicate that the quality of family relationships and affiliation with one's ethnic group are important predictors of positive adjustment for Ma̅ori youth over time. These results are discussed in the context of positive youth development for ethnic minority and indigenous youth.

  3. Interactions between Streptococcus oralis, Actinomyces oris, and Candida albicans in the development of multispecies oral microbial biofilms on salivary pellicle.

    PubMed

    Cavalcanti, I M G; Del Bel Cury, A A; Jenkinson, H F; Nobbs, A H

    2017-02-01

    The fungus Candida albicans is carried orally and causes a range of superficial infections that may become systemic. Oral bacteria Actinomyces oris and Streptococcus oralis are abundant in early dental plaque and on oral mucosa. The aims of this study were to determine the mechanisms by which S. oralis and A. oris interact with each other and with C. albicans in biofilm development. Spatial distribution of microorganisms was visualized by confocal laser scanning microscopy of biofilms labeled by differential fluorescence or by fluorescence in situ hybridization (FISH). Actinomyces oris and S. oralis formed robust dual-species biofilms, or three-species biofilms with C. albicans. The bacterial components tended to dominate the lower levels of the biofilms while C. albicans occupied the upper levels. Non-fimbriated A. oris was compromised in biofilm formation in the absence or presence of streptococci, but was incorporated into upper biofilm layers through binding to C. albicans. Biofilm growth and hyphal filament production by C. albicans was enhanced by S. oralis. It is suggested that the interkingdom biofilms are metabolically coordinated to house all three components, and this study demonstrates that adhesive interactions between them determine spatial distribution and biofilm architecture. The physical and chemical communication processes occurring in these communities potentially augment C. albicans persistence at multiple oral cavity sites.

  4. Complete Genome Sequence of Lactobacillus oris J-1, a Potential Probiotic Isolated from the Human Oral Microbiome

    PubMed Central

    2016-01-01

    Lactobacilli can exert health-promoting effects in the human oral microbiome through many mechanisms, including pathogen inhibition, maintenance of microbial balance, immunomodulation, and enhancement of the epithelial barrier function. Here, we present the complete genome sequence of a potential probiotic, Lactobacillus oris J-1, that was isolated from the oral cavity of a health child. PMID:27634996

  5. Influence of playing wind instruments on activity of masticatory muscles.

    PubMed

    Gotouda, A; Yamaguchi, T; Okada, K; Matsuki, T; Gotouda, S; Inoue, N

    2007-09-01

    The aim of this study was to elucidate the influence of change in sound tone of playing wind instruments on activity of jaw-closing muscles and the effect of sustained playing for a long time on fatigue of jaw-closing muscles. Electromyograms (EMG) of 19 brass instrument players and 14 woodwind instrument players were measured while playing instruments in tuning tone and high tone and under other conditions. Nine brass instrument players and nine woodwind instrument players played instruments for 90 min. Before and after the exercise, power spectral analyses of EMG from masseter muscles at 50% of maximum voluntary clenching level were performed and mean power frequency (MPF) were calculated. Root mean square (RMS) of EMG in masseter and temporal muscles while playing were slightly larger than those at rest but extremely small in comparison with those during maximum clenching. Root mean square in orbicularis oris and digastric muscles were relatively large when playing instruments. In the brass instrument group, RMS in high tone was significantly higher than that in tuning tone in all muscles examined. In the woodwind instrument group, RMS in high tone was not significantly higher than that in tuning tone in those muscles. Mean power frequency was not decreased after sustained playing in both instrument groups. These findings indicate that contractive load to jaw-closing muscles when playing a wind instrument in both medium and high tone is very small and playing an instrument for a long time does not obviously induce fatigue of jaw-closing muscles.

  6. The Radio Jet Associated with the Multiple V380 Ori System

    NASA Astrophysics Data System (ADS)

    Rodríguez, Luis F.; Yam, J. Omar; Carrasco-González, Carlos; Anglada, Guillem; Trejo, Alfonso

    2016-10-01

    The giant Herbig-Haro object 222 extends over ˜6‧ in the plane of the sky, with a bow shock morphology. The identification of its exciting source has remained uncertain over the years. A non-thermal radio source located at the core of the shock structure was proposed to be the exciting source. However, Very Large Array studies showed that the radio source has a clear morphology of radio galaxy and a lack of flux variations or proper motions, favoring an extragalactic origin. Recently, an optical-IR study proposed that this giant HH object is driven by the multiple stellar system V380 Ori, located about 23‧ to the SE of HH 222. The exciting sources of HH systems are usually detected as weak free-free emitters at centimeter wavelengths. Here, we report the detection of an elongated radio source associated with the Herbig Be star or with its close infrared companion in the multiple V380 Ori system. This radio source has the characteristics of a thermal radio jet and is aligned with the direction of the giant outflow defined by HH 222 and its suggested counterpart to the SE, HH 1041. We propose that this radio jet traces the origin of the large scale HH outflow. Assuming that the jet arises from the Herbig Be star, the radio luminosity is a few times smaller than the value expected from the radio-bolometric correlation for radio jets, confirming that this is a more evolved object than those used to establish the correlation.

  7. A Spectroscopic Study of the Secondary Star of BM Ori: Preliminary Results

    NASA Astrophysics Data System (ADS)

    Vitrichenko, E. A.; Klochkova, V. G.

    2001-05-01

    Two CCD spectra of the star BM Ori were obtained with the echelle spectrograph of the 6-m telescope. In one of the spectra, a large proportion of lines are distorted by emission. The emission component is blueshifted by 50 km/s, suggesting hot-gas outflow from the atmosphere. The equivalent-width ratio of measured lines in the spectra outside and during eclipse is consistent with the assumption that ~2/3 of the primary star's area is obscured during eclipse, as follows from light curves. Measured line equivalent widths were used to estimate atmospheric parameters of the secondary star, T_eff = 7300 K, log g = 5.2, and microturbulence xi_t = 6 km/s, and to determine its chemical composition. The C, Na, Al, Si, S, Ca, Fe, Ni, and Zn abundances are solar, within the error limits. Li, Sc, Ti, V, Cr, Mn, Co, and Y are overabundant, while Mg, Cu, and Ba are underabundant. In general, the secondary is similar in chemical composition to the star V1016 Ori. Based on the secondary's mass determined by solving the radial-velocity curve and on log g estimated spectroscopically from iron ionization equilibrium, we calculated its photospheric radius, R_2 = 0.5 R_solar. However, the spectroscopic log g = 5.2 disagrees with log g = 3.5 calculated from the luminosity and effective temperature and with log g = 3.0 calculated from light and radial-velocity curves. If the secondary's photospheric radius is indeed small, this argues for the hypothesis that the eclipsing body is a dust envelope. The radial velocities measured from the two spectra are systematically higher than those calculated from the radial-velocity curve by +34 and +24 km/s. It is likely that the secondary's atmosphere occasionally shrinks.

  8. A Herschel View of Protoplanetary Disks in the σ Ori Cluster

    NASA Astrophysics Data System (ADS)

    Maucó, Karina; Hernández, Jesús; Calvet, Nuria; Ballesteros-Paredes, Javier; Briceño, César; McClure, Melissa; D'Alessio, Paola; Anderson, Kassandra; Ali, Babar

    2016-09-01

    We present new Herschel observations using the Photodetector Array Camera and Spectrometer of 32 T Tauri stars in the young (˜3 Myr) σ Ori cluster. Most of our objects are K and M stars with large excesses at 24 μm. We used irradiated accretion disk models of D’Alessio et al. to compare their spectral energy distributions with our observational data. We arrive at the following six conclusions. (i) The observed disks are consistent with irradiated accretion disk systems. (ii) Most of our objects (60%) can be explained by significant dust depletion from the upper disk layers. (iii) Similarly, 61% of our objects can be modeled with large disk sizes (R d ≥ 100 au). (iv) The masses of our disks range between 0.03 and 39 M Jup, where 35% of our objects have disk masses less than 1 M Jup. Although these are lower limits, high-mass (>0.05 {M}⊙ ) disks, which are present in, e.g., Taurus, are missing. (v) By assuming a uniform distribution of objects around the brightest stars at the center of the cluster, we found that 80% of our disks are exposed to external FUV radiation of 300≤slant {G}0≤slant 1000, which can be strong enough to photoevaporate the outer edges of the closer disks. (vi) Within 0.6 pc from σ Ori we found forbidden emission lines of [N ii] in the spectrum of one of our large disks (SO662), but no emission in any of our small ones. This suggests that this object may be an example of a photoevaporating disk.

  9. Ethnic density and area deprivation: neighbourhood effects on Māori health and racial discrimination in Aotearoa/New Zealand.

    PubMed

    Bécares, Laia; Cormack, Donna; Harris, Ricci

    2013-07-01

    Some studies suggest that ethnic minority people are healthier when they live in areas with a higher concentration of people from their own ethnic group, a so-called ethnic density effect. To date, no studies have examined the ethnic density effect among indigenous peoples, for whom connections to land, patterns of settlement, and drivers of residential location may differ from ethnic minority populations. The present study analysed the Māori sample from the 2006/07 New Zealand Health Survey to examine the association between increased Māori ethnic density, area deprivation, health, and experiences of racial discrimination. Results of multilevel regressions showed that an increase in Māori ethnic density was associated with decreased odds of reporting poor self-rated health, doctor-diagnosed common mental disorders, and experienced racial discrimination. These associations were strengthened after adjusting for area deprivation, which was consistently associated with increased odds of reporting poor health and reports of racial discrimination. Our findings show that whereas ethnic density is protective of the health and exposure to racial discrimination of Māori, this effect is concealed by the detrimental effect of area deprivation, signalling that the benefits of ethnic density must be interpreted within the current socio-political context. This includes the institutional structures and racist practices that have created existing health and socioeconomic inequities in the first place, and maintain the unequal distribution of concentrated poverty in areas of high Māori density. Addressing poverty and the inequitable distribution of socioeconomic resources by ethnicity and place in New Zealand is vital to improving health and reducing inequalities. Given the racialised nature of access to goods, services, and opportunities within New Zealand society, this also requires a strong commitment to eliminating racism. Such commitment and action will allow the benefits

  10. Ethnic density and area deprivation: Neighbourhood effects on Māori health and racial discrimination in Aotearoa/New Zealand

    PubMed Central

    Bécares, Laia; Cormack, Donna; Harris, Ricci

    2013-01-01

    Some studies suggest that ethnic minority people are healthier when they live in areas with a higher concentration of people from their own ethnic group, a so-called ethnic density effect. To date, no studies have examined the ethnic density effect among indigenous peoples, for whom connections to land, patterns of settlement, and drivers of residential location may differ from ethnic minority populations. The present study analysed the Māori sample from the 2006/07 New Zealand Health Survey to examine the association between increased Māori ethnic density, area deprivation, health, and experiences of racial discrimination. Results of multilevel regressions showed that an increase in Māori ethnic density was associated with decreased odds of reporting poor self-rated health, doctor-diagnosed common mental disorders, and experienced racial discrimination. These associations were strengthened after adjusting for area deprivation, which was consistently associated with increased odds of reporting poor health and reports of racial discrimination. Our findings show that whereas ethnic density is protective of the health and exposure to racial discrimination of Māori, this effect is concealed by the detrimental effect of area deprivation, signalling that the benefits of ethnic density must be interpreted within the current socio-political context. This includes the institutional structures and racist practices that have created existing health and socioeconomic inequities in the first place, and maintain the unequal distribution of concentrated poverty in areas of high Māori density. Addressing poverty and the inequitable distribution of socioeconomic resources by ethnicity and place in New Zealand is vital to improving health and reducing inequalities. Given the racialised nature of access to goods, services, and opportunities within New Zealand society, this also requires a strong commitment to eliminating racism. Such commitment and action will allow the benefits

  11. Muscle biopsy

    MedlinePlus

    ... Inflammatory diseases of muscle (such as polymyositis or dermatomyositis ) Diseases of the connective tissue and blood vessels ( ... disease that involves inflammation and a skin rash ( dermatomyositis ) Inherited muscle disorder ( Duchenne muscular dystrophy ) Inflammation of ...

  12. Modeling Muscles

    ERIC Educational Resources Information Center

    Goodwyn, Lauren; Salm, Sarah

    2007-01-01

    Teaching the anatomy of the muscle system to high school students can be challenging. Students often learn about muscle anatomy by memorizing information from textbooks or by observing plastic, inflexible models. Although these mediums help students learn about muscle placement, the mediums do not facilitate understanding regarding integration of…

  13. Onset sequencing of selected lip muscles in stutterers and nonstutterers.

    PubMed

    Guitar, B; Guitar, C; Neilson, P; O'Dwyer, N; Andrews, G

    1988-03-01

    The present study examined lip muscle activity during the speech production of stutterers and fluent speakers to provide information about the nature of stuttering blocks. Depressor Anguli Oris (DAO) and Depressor Labii Inferioris (DLI) were recorded, using hooked-wire electromyography (EMG), in 3 stutterers and 3 nonstutterers during productions of the words "peek", "puck", and "pack." EMG records indicated that nonstutterers activated DAO prior to DLI for production of the initial/p/. Stutterers frequently reversed this sequence of onset, particularly when they stuttered. Results are discussed in terms of mistiming versus anticipatory hypertension hypotheses about stuttering.

  14. Wāhine hauora: linking local hospital and national health information datasets to explore maternal risk factors and obstetric outcomes of New Zealand Māori and non-Māori women in relation to infant respiratory admissions and timely immunisations

    PubMed Central

    2013-01-01

    Background Significant health inequities exist around maternal and infant health for Māori, the indigenous people of New Zealand. The infants of Māori are more likely to die in their first year of life and also have higher rates of hospital admission for respiratory illnesses, with the greatest burden of morbidity being due to bronchiolitis in those under one year of age. Timely immunisations can prevent some respiratory related hospitalisations, although for Māori, the proportion of infants with age appropriate immunisations are lower than for non-Māori. This paper describes the protocol for a retrospective cohort study that linked local hospital and national health information datasets to explore maternal risk factors and obstetric outcomes in relation to respiratory admissions and timely immunisations for infants of Māori and non-Māori women. Methods/Design The study population included pregnant women who gave birth in hospital in one region of New Zealand between 1995 and 2009. Routinely collected local hospital data were linked via a unique identifier (National Health Index number) to national health information databases to assess rates of post-natal admissions and access to health services for Māori and non-Māori mothers and infants. The two primary outcomes for the study are: 1. The rates of respiratory hospitalisations of infants (≤ 1 yr of age) calculated for infants of both Māori and non-Māori women (for mothers under 20 years of age, and overall) accounting for relationship to parity, maternal age, socioeconomic deprivation index, maternal smoking status. 2. The proportion of infants with age appropriate immunisations at six and 12 months, calculated for both infants born to Māori women and infants born to non-Māori women, accounting for relationship to parity, maternal age, socioeconomic deprivation index, smoking status, and other risk factors. Discussion Analysis of a wide range of routinely collected health information in which

  15. X-ray, UV and optical analysis of supergiants: ɛ Ori

    NASA Astrophysics Data System (ADS)

    Puebla, Raul E.; Hillier, D. John; Zsargó, Janos; Cohen, David H.; Leutenegger, Maurice A.

    2016-03-01

    We present a multi-wavelength (X-ray to optical) analysis, based on non-local thermodynamic equilibrium photospheric+wind models, of the B0 Ia-supergiant: ɛ Ori. The aim is to test the consistency of physical parameters, such as the mass-loss rate and CNO abundances, derived from different spectral bands. The derived mass-loss rate is {dot {M}} / {√{f_{∞}}} {˜} 1.6 × 10-6 M⊙ yr-1 where f∞ is the volume filling factor. However, the S IV λλ1062,1073 profiles are too strong in the models; to fit the observed profiles it is necessary to use f∞ <0.01. This value is a factor of 5 to 10 lower than inferred from other diagnostics, and implies {dot{M}} ≲ 1 × 10^{-7} M⊙ yr-1. The discrepancy could be related to porosity-vorosity effects or a problem with the ionization of sulphur in the wind. To fit the UV profiles of N V and O VI it was necessary to include emission from an interclump medium with a density contrast (ρcl/ρICM) of ˜100. X-ray emission in H/He like and Fe L lines was modelled using four plasma components located within the wind. We derive plasma temperatures from 1 × 106 to 7 × 106 K, with lower temperatures starting in the outer regions (R0 ˜ 3-6 R*), and a hot component starting closer to the star (R0 ≲ 2.9 R*). From X-ray line profiles we infer {dot{M}} < 4.9 × 10-7 M⊙ yr-1. The X-ray spectrum (≥0.1 kev) yields an X-ray luminosity LX ˜ 2.0 × 10-7Lbol, consistent with the superion line profiles. X-ray abundances are in agreement with those derived from the UV and optical analysis: ɛ Ori is slightly enhanced in nitrogen and depleted in carbon and oxygen, evidence for CNO processed material.

  16. The buccinator muscle: an original morphogenetical study.

    PubMed

    Plas, E; Deliac, P; Garuet Lempirou, A; Caix, P; Bioulac, B

    2004-04-01

    The buccinator muscle, a cutaneous muscle derived from the second arc, is innervated by the facial nerve. It is made of 3 bundles extended into the cheek, from the pterygo-mandibular ligament to the modiolus. It is used for diverse buccal functions. This study attempts to give a better insight of the embryogenesis and the development of the muscle. After taking samples by microdissection under binocular microscope, of this region of embryos and foeti, we performed histological sections. They were then coloured by Masson's trichome for their observation under photon microscopy. From seventieth week we observed the presence of a peri-mucous mesenchyma between the cartilaginous condensation of the "pre premier arc" and Meckel's cartilage. The buccinator presents an insertion on the modiolus, sliding under the latter it runs forwards, it is at the origin of the formation of the orbicularis internus of the lips (musculus orbicularis oris). This muscle displaces its posterior insertion downwards, with the development of the face in the child and the adolescent, notably with the modification in vertical dimension due to the arrival of the deciduous teeth before the permanent dentition. Furthermore it appears that buccinator does not play a role as a sphincter in the secretion of the parotid glands.

  17. ori science education in Aotearoa New Zealand. He pūtea whakarawe: aspirations and realities

    NASA Astrophysics Data System (ADS)

    Wood, Anaru; Lewthwaite, Brian

    2008-09-01

    This article reports on the first two phases of a multiphase science education development project in predominantly Māori kura (school communities) in the central region of the North Island of Aotearoa New Zealand. The development project in its entirety employs an action research methodology and by so doing endeavors to support the improvement of science education delivery in accordance with school community aspirations. The full project (a) establishes the current situation in Year 1-8 science education in the communities; (b) identifies developmental aspirations for stakeholders within the communities and identifies potential contributors and constraints to these aspirations; (c) implements mechanisms for achieving identified aspirations; and finally; (d) evaluates the effectiveness of such mechanisms. In its focus on the first two phases, this article incorporates the analytical lenses of Kaupapa Māori Theory and Bronfenbrenner's bio-ecological model. It concludes by outlining some priorities to consider for science education development based on the outcomes of our preliminary discussions.

  18. ori patients' experiences and perspectives of chronic kidney disease: a New Zealand qualitative interview study

    PubMed Central

    Walker, Rachael C; Walker, Shayne; Morton, Rachael L; Tong, Allison; Howard, Kirsten; Palmer, Suetonia C

    2017-01-01

    Objectives To explore and describe Māori (the indigenous people of New Zealand) patients' experiences and perspectives of chronic kidney disease (CKD), as these are largely unknown for indigenous groups with CKD. Design Face-to-face, semistructured interviews with purposive sampling and thematic analysis. Setting 3 dialysis centres in New Zealand (NZ), all of which offered all forms of dialysis modalities. Participants 13 Māori patients with CKD and who were either nearing the need for dialysis or had started dialysis within the previous 12 months. Results The Māori concepts of whakamā (disempowerment and embarrassment) and whakamana (sense of self-esteem and self-determination) provided an overarching framework for interpreting the themes identified: disempowered by delayed CKD diagnosis (resentment of late diagnosis; missed opportunities for preventive care; regret and self-blame); confronting the stigma of kidney disease (multigenerational trepidation; shame and embarrassment; fear and denial); developing and sustaining relationships to support treatment decision-making (importance of family/whānau; valuing peer support; building clinician–patient trust); and maintaining cultural identity (spiritual connection to land; and upholding inner strength/mana). Conclusions Māori patients with CKD experienced marginalisation within the NZ healthcare system due to delayed diagnosis, a focus on individuals rather than family, multigenerational fear of dialysis, and an awareness that clinicians are not aware of cultural considerations and values during decision-making. Prompt diagnosis to facilitate self-management and foster trust between patients and clinicians, involvement of family and peers in dialysis care, and acknowledging patient values could strengthen patient engagement and align decision-making with patient priorities. PMID:28104711

  19. The Combating Obesity in Māori and Pasifika Adolescent School-Children Study: COMPASS Methodology and Study Protocol

    PubMed Central

    Stoner, Lee; Shultz, Sarah P.; Lambrick, Danielle M.; Krebs, Jeremy; Weatherall, Mark; Palmer, Barry R.; Lane, Andrew M.; Kira, Geoff; Witter, Trevor; Williams, Michelle A.

    2013-01-01

    Background: Lifestyle modifications including, physical activity can reduce obesity-related morbidity and subsequent cardiovascular disease in youth. This study will investigate the efficacy of a culturally-sensitive, non-contact, boxing-orientated training program on obesity and related cardio-metabolic conditions in Māori and Pasifika adolescents. Details of the methodological aspects of recruitment, inclusion criteria, randomization, cultural sensitivity, intervention program, assessments, process evaluation, and statistical analyses are described. Methods: This study will be a community based, New Zealand, randomized control trial (RCT). Male and female obese (body mass index >95th percentile) Māori and Pasifika adolescents aged 14-16 years will be recruited and the sample size will be confirmed through a feasibility study. Combating Obesity in Māori and Pasifika Adolescent School-children Study (COMPASS) is a 6-month, theory-based program, conducted 3-times/week in a culturally appropriate setting. Each session includes 40 min boxing-orientated training and 30 min resistance training. Assessments will be made at baseline, 3-months, 6-months, 12-months, and 24-months. Main outcomes include abdominal obesity, endothelial function, and insulin resistance. Other outcomes include arterial stiffness, lipid profile, inflammatory biomarkers, well-being, and aerobic fitness. Control measures include physical activity, sleep behavior, and dietary intake. Results: As a protocol paper there are no specific results to present, our purpose is to share our RCT design with the scientific community. Conclusions: COMPASS will be used to provide direction for exercise prescription policy in at-risk Māori and Pasifika adolescents. PMID:23930168

  20. HST/STIS ULTRAVIOLET SPECTROSCOPY OF THE COMPONENTS OF THE MASSIVE TRIPLE STAR δ ORI A

    SciTech Connect

    Richardson, Noel D.; Moffat, Anthony F. J.; Gull, Theodore R.; Lindler, Don J.; Gies, Douglas R.; Corcoran, Michael F.

    2015-07-20

    The multiple star system of δ Orionis is one of the closest examples of a system containing a luminous O-type, bright giant star (component Aa1). It is often used as a spectral-type standard and has the highest observed X-ray flux of any hot-star binary. The main component Aa1 is orbited by two lower mass stars, faint Aa2 in a 5.7 day eclipsing binary, and Ab, an astrometric companion with an estimated period of 346 years. Generally the flux from all three stars is recorded in ground-based spectroscopy, and the spectral decomposition of the components has proved difficult. Here we present Hubble Space Telescope/Space Telescope Imaging Spectrograph ultraviolet spectroscopy of δ Ori A that provides us with spatially separated spectra of Aa and Ab for the first time. We measured radial velocities for Aa1 and Ab in two observations made near the velocity extrema of Aa1. We show tentative evidence for the detection of the Aa2 component in cross-correlation functions of the observed and model spectra. We discuss the appearance of the UV spectra of Aa1 and Ab with reference to model spectra. Both stars have similar effective temperatures, but Ab is fainter and is a rapid rotator. The results will help in the interpretation of ground-based spectroscopy and in understanding the physical and evolutionary parameters of these massive stars.

  1. The impact of Māori cultural values on forensic science practice in New Zealand.

    PubMed

    Hudson, Maui L; Allan, Christine A; Bedford, Keith R; Buckleton, John S; Stuart, Keriata

    2008-03-01

    Forensic science aims to serve society by advancing justice. It is accepted that some actions taken by the state in the interests of advancing justice, such as postmortem examinations, may impinge on values held by members of groups within society. Such actions have the potential to cause cultural offense. It is important that forensic scientists are aware of these issues and that as a profession we should take actions, where possible, to reduce any potential offense and consequently reduce unnecessary distress. This paper examines the impact of these issues on forensic practice in New Zealand, and, in particular, in relation to the cultural values of Māori, the indigenous people of New Zealand. Interviews and workshops were used to identify forensic practices involving a risk of cultural offense. Particular issues were identified in regard to crime scene attendance and examination, postmortem attendance and sample storage, disposal, and return. This paper describes the response developed by the Institute of Environmental Science and Research Limited (ESR) to address these issues, including a cultural awareness training package and reference brochure.

  2. V2494 Cyg: a unique FU Ori type object in the Cygnus OB7 complex

    NASA Astrophysics Data System (ADS)

    Magakian, Tigran Yu.; Nikogossian, Elena H.; Movsessian, Tigran; Moiseev, Alexei; Aspin, Colin; Davis, Chris J.; Pyo, Tae-Soo; Khanzadyan, Tigran; Froebrich, Dirk; Smith, Michael D.; Moriarty-Schieven, Gerald H.; Beck, Tracy L.

    2013-07-01

    A photometric and spectral study of the variable star V2494 Cyg in the L 1003 dark cloud is presented. The brightness of the star, formerly known as HH 381 IRS, increased by 2.5 mag in R (probably in the 1980s) and since then has remained nearly constant. Since the brightness increase, V2494 Cyg has illuminated a bipolar cometary nebula. The stellar spectrum has several features typical of the FU Ori (FUor) type, plus it exhibits very strong Hα and forbidden emission lines with high-velocity components. These emission lines originate in the Herbig-Haro (HH) jet near the star. The kinematic age of the jet is consistent with it forming at the time of the outburst leading to the luminosity increase. V2494 Cyg also produces a rather extended outflow; it is the first known FUor with both an observed outburst and a parsec-sized HH flow. The nebula, illuminated by V2494 Cyg, possesses similar morphological and spectral characteristics to Hubble's variable nebula (R Monocerotis/NGC 2261).

  3. The 'warrior gene' and the Mãori people: the responsibility of the geneticists.

    PubMed

    Perbal, Laurence

    2013-09-01

    The 'gene of' is a teleosemantic expression that conveys a simplistic and linear relationship between a gene and a phenotype. Throughout the 20th century, geneticists studied these genes of traits. The studies were often polemical when they concerned human traits: the 'crime gene', 'poverty gene', 'IQ gene', 'gay gene' or 'gene of alcoholism'. Quite recently, a controversy occurred in 2006 in New Zealand that started with the claim that a 'warrior gene' exists in the Mãori community. This claim came from a geneticist working on the MAOA gene. This article is interested in the responsibility of that researcher regarding the origin of the controversy. Several errors were made: overestimation of results, abusive use of the 'gene of' kind of expression, poor communication with the media and a lack of scientific culture. The issues of the debate were not taken into account sufficiently, either from the political, social, ethical or even the genetic points of view. After more than 100 years of debates around 'genes of' all kinds (here, the 'warrior gene'), geneticists may not hide themselves behind the media when a controversy occurs. Responsibilities have to be assumed.

  4. VizieR Online Data Catalog: 25 Ori group low-mass stars (Downes+, 2014)

    NASA Astrophysics Data System (ADS)

    Downes, J. J.; Briceno, C.; Mateu, C.; Hernandez, J.; Vivas, A. K.; Calvet, N.; Hartmann, L.; Petr-Gotzens, M. G.; Allen, L.

    2015-04-01

    Multi-epoch optical V-, R-, I-band and Hα observations across the entire Orion OB1 association (spanning ~180deg2) were obtained as part of the CVSO (Briceno et al., 2005AJ....129..907B, Cat. J/AJ/129/907), being conducted since 1998 with the Jurgen Stock 1.0/1.5 Schmidt-type telescope and the 8000x8000-pixel QUEST-I CCD Mosaic camera, at the National Astronomical Observatory of Venezuela. During 2009 a new dedicated 4m survey telescope, the Visible and Infrared Survey Telescope for Astronomy (VISTA), located at ESO's Paranal Observatory, was commissioned by the VISTA consortium. For the Galactic Science Verification of VISTA, an ~30deg2 area of the Orion OB1 association, which included the Orion Belt region, part of the Orion A cloud, the 25 Orionis and σ Ori clusters, was imaged in the Z, Y, J, H and Ks filters, during 2009 October 16 to November 2. (3 data files).

  5. Interkingdom cooperation between Candida albicans, Streptococcus oralis and Actinomyces oris modulates early biofilm development on denture material.

    PubMed

    Cavalcanti, Indira M G; Nobbs, Angela H; Ricomini-Filho, Antônio Pedro; Jenkinson, Howard F; Del Bel Cury, Altair A

    2016-04-01

    Candida-associated stomatitis affects up to 60% of denture wearers, and Candida albicans remains the most commonly isolated fungal species. The oral bacteria Actinomyces oris and Streptococcus oralis are abundant in early dental plaque. The aims of this study were to determine the effects of S. oralis and A. oris on the development of C. albicans biofilms on denture material. Resin discs were coated with saliva and at early (1.5 h) or later (24 h) stages of biofilm development, cell numbers of each species were determined. Spatial distribution of microorganisms was visualized by confocal scanning laser microscopy of biofilms labelled by differential fluorescence or by fluorescence in situ hybridization. Interkingdom interactions underpinning biofilm development were also evaluated planktonically utilizing fluorescence microscopy. Synergistic interactions between all three species occurred within biofilms and planktonically. Bacterial cells coaggregated with each other and adhered singly or in coaggregates to C. albicans hyphal filaments. Streptococcus oralis appeared to enhance hyphal filament production and C. albicans biovolume was increased 2-fold. Concomitantly, cell numbers of S. oralis and A. oris were enhanced by C. albicans. Thus, cooperative physical and metabolic processes occurring between these three microbial species intensify pathogenic plaque communities on denture surfaces.

  6. In vivo dynamics of EBNA1-oriP interaction during latent and lytic replication of Epstein-Barr virus.

    PubMed

    Daikoku, Tohru; Kudoh, Ayumi; Fujita, Masatoshi; Sugaya, Yutaka; Isomura, Hiroki; Tsurumi, Tatsuya

    2004-12-24

    The Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is required for maintenance of the viral genome DNA during the latent phase of EBV replication but continues to be synthesized after the induction of viral productive replication. An EBV genome-wide chromatin immunoprecipitation assay revealed that EBNA1 constantly binds to oriP of the EBV genome during not only latent but also lytic infection. Although the total levels of EBNA1 proved constant throughout the latter, the levels of the oriP-bound form were increased as lytic infection proceeded. EBV productive DNA replication occurs at discrete sites in nuclei, called replication compartments, where viral replication proteins are clustered. Confocal laser microscopic analyses revealed that whereas EBNA1 was distributed broadly in nuclei as fine punctate dots during the latent phase of infection, the protein became redistributed to the viral replication compartments and localized as distinct spots within and/or nearby the compartments after the induction of lytic replication. Taking these findings into consideration, oriP regions of the EBV genome might be organized by EBNA1 into replication domains that may set up scaffolding for lytic replication and transcription.

  7. Reduced LPS phosphorylation in Escherichia coli lowers the elevated ori/ter ratio in seqA mutants

    PubMed Central

    Rotman, Ella; Bratcher, Preston; Kuzminov, Andrei

    2009-01-01

    Summary The seqA defect in E. coli increases the ori/ter ratio and causes chromosomal fragmentation, making seqA mutants dependent on recombinational repair (the seqA recA co-lethality). To understand the nature of this chromosomal fragmentation, we characterized ΔseqA mutants and isolated suppressors of the ΔseqA recA lethality. We demonstrate that our ΔseqA alleles have normal function of the downstream pgm gene and normal ratios of the major phospholipids in the membranes, but increased surface lipopolysaccharide (LPS) phosphorylation. The predominant class of ΔseqA recA suppressors disrupts the rfaQGP genes, reducing phosphorylation of the inner core region of LPS. The rfaQGP suppressors also reduce the elevated ori/ter ratio of the ΔseqA mutants, but, unexpectedly, the suppressed mutants still exhibit the high levels of chromosomal fragmentation and SOS induction, characteristic of the ΔseqA mutants. We also found that co-lethality of rfaP with defects in the production of acidic phospholipids is suppressed by alternative initiation of chromosomal replication, suggesting that LPS phosphorylation stimulates replication initiation. The rfaQGP suppression of the seqA recA lethality provides genetic support for the surprising physical evidence that the oriC DNA forms complexes with the outer membrane. PMID:19432803

  8. Din7 and Mhr1 expression levels regulate double-strand-break-induced replication and recombination of mtDNA at ori5 in yeast.

    PubMed

    Ling, Feng; Hori, Akiko; Yoshitani, Ayako; Niu, Rong; Yoshida, Minoru; Shibata, Takehiko

    2013-06-01

    The Ntg1 and Mhr1 proteins initiate rolling-circle mitochondrial (mt) DNA replication to achieve homoplasmy, and they also induce homologous recombination to maintain mitochondrial genome integrity. Although replication and recombination profoundly influence mitochondrial inheritance, the regulatory mechanisms that determine the choice between these pathways remain unknown. In Saccharomyces cerevisiae, double-strand breaks (DSBs) introduced by Ntg1 at the mitochondrial replication origin ori5 induce homologous DNA pairing by Mhr1, and reactive oxygen species (ROS) enhance production of DSBs. Here, we show that a mitochondrial nuclease encoded by the nuclear gene DIN7 (DNA damage inducible gene) has 5'-exodeoxyribonuclease activity. Using a small ρ(-) mtDNA bearing ori5 (hypersuppressive; HS) as a model mtDNA, we revealed that DIN7 is required for ROS-enhanced mtDNA replication and recombination that are both induced at ori5. Din7 overproduction enhanced Mhr1-dependent mtDNA replication and increased the number of residual DSBs at ori5 in HS-ρ(-) cells and increased deletion mutagenesis at the ori5 region in ρ(+) cells. However, simultaneous overproduction of Mhr1 suppressed all of these phenotypes and enhanced homologous recombination. Our results suggest that after homologous pairing, the relative activity levels of Din7 and Mhr1 modulate the preference for replication versus homologous recombination to repair DSBs at ori5.

  9. Let's kōrero (talk): the practice and functions of reminiscing among mothers and children in Māori families.

    PubMed

    Reese, Elaine; Neha, Tia

    2015-01-01

    ori adults recall earlier memories than New Zealand European or Chinese adults, highlighting the importance of memory in Māori culture. In this study, Māori preschool children and their mothers (N = 41) reminisced about a diverse range of past events, including everyday events, the child's birth, cultural rituals and the child's misbehaviour. Mothers also reported how frequently they discussed past events with their children, as well as their level of affiliation with Māori culture. Mothers who reported higher levels of cultural affiliation also reported reminiscing more frequently about a diverse range of past events. Mothers reminisced in more elaborative ways about everyday events with their children compared to birth stories, cultural rituals and misbehaviours. Maternal reminiscing about cultural rituals and misbehaviours, however, along with maternal reminiscing about everyday events and birth stories, were significantly correlated with children's memory across conversations. These results underscore the continued importance of reminiscing about culturally relevant events in Māori culture, and the newfound importance for Māori families of reminiscing about everyday events.

  10. Cancer in Māori: lessons from prostate, colorectal and gastric cancer and progress in hereditary stomach cancer in New Zealand.

    PubMed

    Blair, Vanessa; Kahokehr, Arman; Sammour, Tarik

    2013-01-01

    Persisting ethnic disparities in cancer incidence and outcomes exist between Māori and non-Māori in Aotearoa/New Zealand. It is difficult to disentangle the complex interplay of environmental and genetic factors that contribute to the variation in cancer statistics between these two groups. In Māori, the sites of highest cancer incidence are the prostate in men, breast in women and lung in both - the next most common cancers in Māori are colorectal and stomach cancer. This paper discusses colorectal, prostate and stomach cancer in Māori to illustrate selected issues that impact on cancer care. Colorectal cancer is discussed to illustrate the importance of accurate cancer statistics to focus management strategies. Prostate cancer in Māori is reviewed - an area where cultural factors impact on care delivery. Sporadic stomach cancer in New Zealand is used to show how sub-classification of different types of cancer can be important and illustrate the breadth of putative causal factors. Then follows an overview of developments in hereditary gastric cancer in New Zealand in the last 15 years, showing how successful clinical and research partnerships can improve patient outcomes. One example is the Kimi Hauora Clinic, which provides support to cancer patients, mutation carriers and their families, helping them navigate the interface with the many health-care professionals involved in the multidisciplinary care of cancer patients in the 21st century.

  11. migS, a cis-acting site that affects bipolar positioning of oriC on the Escherichia coli chromosome

    PubMed Central

    Yamaichi, Yoshiharu; Niki, Hironori

    2004-01-01

    During replication of the Escherichia coli chromosome, the replicated Ori domains migrate towards opposite cell poles, suggesting that a cis-acting site for bipolar migration is located in this region. To identify this cis-acting site, a series of mutants was constructed by splitting subchromosomes from the original chromosome. One mutant, containing a 720 kb subchromosome, was found to be defective in the bipolar positioning of oriC. The creation of deletion mutants allowed the identification of migS, a 25 bp sequence, as the cis-acting site for the bipolar positioning of oriC. When migS was located at the replication terminus, the chromosomal segment showed bipolar positioning. migS was able to rescue bipolar migration of plasmid DNA containing a mutation in the SopABC partitioning system. Interestingly, multiple copies of the migS sequence on a plasmid in trans inhibited the bipolar positioning of oriC. Taken together, these findings indicate that migS plays a crucial role in the bipolar positioning of oriC. In addition, real-time analysis of the dynamic morphological changes of nucleoids in wild-type and migS mutants suggests that bipolar positioning of the replicated oriC contributes to nucleoid organization. PMID:14685268

  12. Role for a region of helically unstable DNA within the Epstein-Barr virus latent cycle origin of DNA replication oriP in origin function

    SciTech Connect

    Polonskaya, Zhanna; Benham, Craig J.; Hearing, Janet . E-mail: jhearing@ms.cc.sunysb.edu

    2004-10-25

    The minimal replicator of the Epstein-Barr virus (EBV) latent cycle origin of DNA replication oriP is composed of two binding sites for the Epstein-Barr virus nuclear antigen-1 (EBNA-1) and flanking inverted repeats that bind the telomere repeat binding factor TRF2. Although not required for minimal replicator activity, additional binding sites for EBNA-1 and TRF2 and one or more auxiliary elements located to the right of the EBNA-1/TRF2 sites are required for the efficient replication of oriP plasmids. Another region of oriP that is predicted to be destabilized by DNA supercoiling is shown here to be an important functional component of oriP. The ability of DNA fragments of unrelated sequence and possessing supercoiled-induced DNA duplex destabilized (SIDD) structures, but not fragments characterized by helically stable DNA, to substitute for this component of oriP demonstrates a role for the SIDD region in the initiation of oriP-plasmid DNA replication.

  13. The MaoP/maoS Site-Specific System Organizes the Ori Region of the E. coli Chromosome into a Macrodomain

    PubMed Central

    Valens, Michèle; Thiel, Axel

    2016-01-01

    The Ori region of bacterial genomes is segregated early in the replication cycle of bacterial chromosomes. Consequently, Ori region positioning plays a pivotal role in chromosome dynamics. The Ori region of the E. coli chromosome is organized as a macrodomain with specific properties concerning DNA mobility, segregation of loci and long distance DNA interactions. Here, by using strains with chromosome rearrangements and DNA mobility as a read-out, we have identified the MaoP/maoS system responsible for constraining DNA mobility in the Ori region and limiting long distance DNA interactions with other regions of the chromosome. MaoP belongs to a group of proteins conserved in the Enterobacteria that coevolved with Dam methylase including SeqA, MukBEF and MatP that are all involved in the control of chromosome conformation and segregation. Analysis of DNA rings excised from the chromosome demonstrated that the single maoS site is required in cis on the chromosome to exert its effect while MaoP can act both in cis and in trans. The position of markers in the Ori region was affected by inactivating maoP. However, the MaoP/maoS system was not sufficient for positioning the Ori region at the ¼–¾ regions of the cell. We also demonstrate that the replication and the resulting expansion of bulk DNA are localized centrally in the cell. Implications of these results for chromosome positioning and segregation in E. coli are discussed. PMID:27627105

  14. Cis-element, oriR, involved in the initiation of (-) strand poliovirus RNA: a quasi-globular multi-domain RNA structure maintained by tertiary ('kissing') interactions.

    PubMed Central

    Pilipenko, E V; Poperechny, K V; Maslova, S V; Melchers, W J; Slot, H J; Agol, V I

    1996-01-01

    The key steps in the replication of the poliovirus genome, initiation of (-) and (+) strands, require two different cis-acting elements, oriR and oriL, respectively. It has been proposed that the spatial organization of these elements is maintained by tertiary ('kissing') interactions between the loops of two constituent hairpins. Here, the putative partners of the kissing interaction within the oriR of the full-length poliovirus RNA were modified by site-directed mutagenesis. The destabilization of this interaction resulted in a severe suppression of the viral RNA synthesis, but the mutant transcripts proved to be infectious. With a single exception, the potential for the kissing interaction within the oriR of the recovered viruses was partially or completely restored due to either true reversions or second-site compensatory mutations. There was a good correlation between the restoration of this potential and the phenotypic properties of the viruses. It was concluded that the kissing interaction in the poliovirus oriR is functionally important. Using the above experimental data, a three-dimensional structure was derived by molecular modeling techniques, which demonstrated the overall feasibility of the proposed interactions and displayed the poliovirus oriR as a quasi-globular multi-domain structure. Images PMID:8895586

  15. Whakawhanaungatanga: the importance of culturally meaningful connections to improve uptake of pulmonary rehabilitation by Māori with COPD – a qualitative study

    PubMed Central

    Levack, William MM; Jones, Bernadette; Grainger, Rebecca; Boland, Pauline; Brown, Melanie; Ingham, Tristram R

    2016-01-01

    Background Pulmonary rehabilitation is known to improve function and quality of life for people with chronic obstructive pulmonary disease (COPD). However, little research has been conducted on the influence of culture on experiences of pulmonary rehabilitation. This study examined factors influencing uptake of pulmonary rehabilitation by Māori with COPD in New Zealand. Method Grounded theory nested within kaupapa Māori methodology. Transcripts were analyzed from interviews and focus groups with 15 Māori and ten New Zealand non-Māori invited to attend pulmonary rehabilitation for COPD. Māori participants had either attended a mainstream hospital-based program, a community-based program designed “by Māori, for Māori”, or had experienced both. Results Several factors influencing uptake of pulmonary rehabilitation were common to all participants regardless of ethnicity: 1) participants’ past experiences (eg, of exercise; of health care systems), 2) attitudes and expectations, 3) access issues (eg, time, transport, and conflicting responsibilities), and 4) initial program experiences. These factors were moderated by the involvement of family and peers, interactions with health professionals, the way information on programs was presented, and by new illness events. For Māori, however, several additional factors were also identified relating to cultural experiences of pulmonary rehabilitation. In particular, Māori participants placed high value on whakawhanaungatanga: the making of culturally meaningful connections with others. Culturally appropriate communication and relationship building was deemed so important by some Māori participants that when it was absent, they felt strongly discouraged to attend pulmonary rehabilitation. Only the more holistic services offered a program in which they felt culturally safe and to which they were willing to return for ongoing rehabilitation. Conclusion Lack of attention to cultural factors in the delivery of

  16. The CIDA Variability Survey of Orion OB1. I. The Low-Mass Population of Ori OB1a and 1b

    NASA Astrophysics Data System (ADS)

    Briceño, Cesar; Calvet, Nuria; Hernández, J.; Vivas, A. K.; Hartmann, Lee; Downes, J. J.; Berlind, Perry

    2005-02-01

    We present results of a large-scale, multiepoch optical survey of the Orion OB1 association, carried out with the QUEST camera at the Venezuela National Astronomical Observatory. We identify for the first time the widely spread low-mass, young population in the Ori OB1a and OB1b subassociations. Candidate members were picked up by their variability in the V band and position in color-magnitude diagrams. We obtained spectra to confirm membership. In a region spanning ~68 deg2, we found 197 new young stars; of these, 56 are located in the Ori OB1a subassociation and 141 in Ori OB1b. The spatial distribution of the low-mass young stars is spatially coincident with that of the high-mass members but suggests a much sharper edge to the association. Comparison with the spatial extent of molecular gas and extinction maps indicates that the subassociation Ori OB1b is concentrated within a ringlike structure of radius ~2°(~15 pc at 440 pc), centered roughly on the star ɛ Ori in the Orion belt. The ring is apparent in 13CO and corresponds to a region with an extinction AV>=1. The stars exhibiting strong Hα emission, an indicator of active accretion, are found along this ring, whereas the center is populated with weak Hα-emitting stars. In contrast, Ori OB1a is located in a region devoid of gas and dust. We identify a grouping of stars within a ~3 deg2 area located in Ori OB1a, roughly clustered around the B2 star 25 Ori. The Herbig Ae/Be star V346 Ori is also associated with this grouping, which could be an older analog of σ Ori. Using several sets of evolutionary tracks, we find an age of 7-10 Myr for Ori OB1a and of ~4-6 Myr for Ori OB1b, consistent with previous estimates from OB stars. Indicators such as the equivalent width of Hα and near-IR excesses show that the number of accreting low-mass stars decreases sharply between Ori OB1b and Ori OB1a. These results indicate that although a substantial fraction of accreting disks remain at ages ~5 Myr, inner disks are

  17. The ALMA early science view of FUor/EXor objects - I. Through the looking-glass of V2775 Ori

    NASA Astrophysics Data System (ADS)

    Zurlo, Alice; Cieza, Lucas A.; Williams, Jonathan P.; Canovas, Hector; Perez, Sebastian; Hales, Antonio; Mužić, Koraljka; Principe, David A.; Ruíz-Rodríguez, Dary; Tobin, John; Zhang, Yichen; Zhu, Zhaohuan; Casassus, Simon; Prieto, Jose L.

    2017-02-01

    As part of an Atacama Large Millimeter/submillimiter Array (ALMA) survey to study the origin of episodic accretion in young eruptive variables, we have observed the circum-stellar environment of the star V2775 Ori. This object is a very young, pre-main sequence object which displays a large amplitude outburst characteristic of the FUor class. We present Cycle-2 band 6 observations of V2775 Ori with a continuum and CO (2-1) isotopologue resolution of 0.25 arcsec (103 au). We report the detection of a marginally resolved circum-stellar disc in the ALMA continuum with an integrated flux of 106 ± 2 mJy, characteristic radius of ˜30 au, inclination of 14.0^{+7.8}_{-14.5} deg and is oriented nearly face-on with respect to the plane of the sky. The 12CO emission is separated into distinct blue and redshifted regions that appear to be rings or shells of expanding material from quasi-episodic outbursts. The system is oriented in such a way that the disc is seen through the outflow remnant of V2775 Ori, which has an axis along our line of sight. The 13CO emission displays similar structure to that of the 12CO, while the C18O line emission is very weak. We calculated the expansion velocities of the low- and medium-density material with respect to the disc to be of -2.85 (blue), 4.4 (red) and -1.35 and 1.15 km s-1 (for blue and red) and we derived the mass, momentum and kinetic energy of the expanding gas. The outflow has an hourglass shape where the cavities are not seen. We interpret the shapes that the gas traces as cavities excavated by an ancient outflow. We report a detection of line emission from the circumstellar disc and derive a lower limit of the gas mass of 3 MJup.

  18. Investigation of the behaviour of the eruptive young stellar object V1647 Ori since its outburst in 2008

    NASA Astrophysics Data System (ADS)

    Venkataraman, V.

    V1647 Ori is a young eruptive low mass pre-main sequence star that illuminates McNeil's nebula. The object has undergone two outbursts in the recent years - first in November 2003 and the second in mid 2008. While the first outburst lasted for about 2 years before it briefly recovered to its quiescent state, the object is still active since its second eruption in 2008. The nature of the V1647 ori outburst and its similarity with other pre-main sequence eruptive objects, namely FUors and EXors, are still debated. Both types of outburst are thought to be driven by a sudden increase of accretion through a circumstellar disk that feeds through a circumstellar envelope. Follow-up photometric and spectroscopic observations in the near-IR(NIR) JHK bands were being made at Mt. Abu observatory using NICS and NICMOS. The NIR observations taken on several occasions during 2008 to 2012 show mean values of brightness in J, H and K bands of 10.82(sigma=0.146), 9.02(0.189) and 7.58(0.234) mags respectively. During the period, occasional brightening or fading by about 2-3 sigma was also noticed which can be attributed to disk accretion rate variations. The NIR spectra obtained in the K band showed Brackett gamma in emission with non-systematic variability. Our observations indicate slight fading out of V1647 ori during the early part of 2012. Modelling of the spectral energy distribution (SED) in visible to sub-mm region (compiled from archival data) suggests increased disk mass accretion rate as compared to its quiescent state. The model parameters are in good agreement with those derived from observations. These results will be discussed in detail.

  19. The Proximity of Ribosomal Protein Genes to oriC Enhances Vibrio cholerae Fitness in the Absence of Multifork Replication

    PubMed Central

    Soler-Bistué, Alfonso; Timmermans, Michaël

    2017-01-01

    ABSTRACT Recent works suggest that bacterial gene order links chromosome structure to cell homeostasis. Comparative genomics showed that, in fast-growing bacteria, ribosomal protein genes (RP) locate near the replication origin (oriC). We recently showed that Vibrio cholerae employs this positional bias as a growth optimization strategy: under fast-growth conditions, multifork replication increases RP dosage and expression. However, RP location may provide advantages in a dosage-independent manner: for example, the physical proximity of the many ribosomal components, in the context of a crowded cytoplasm, may favor ribosome biogenesis. To uncover putative dosage-independent effects, we studied isogenic V. cholerae derivatives in which the major RP locus, S10-spc-α (S10), was relocated to alternative genomic positions. When bacteria grew fast, bacterial fitness was reduced according to the S10 relative distance to oriC. The growth of wild-type V. cholerae could not be improved by additional copies of the locus, suggesting a physiologically optimized genomic location. Slow growth is expected to uncouple RP position from dosage, since multifork replication does not occur. Under these conditions, we detected a fitness impairment when S10 was far from oriC. Deep sequencing followed by marker frequency analysis in the absence of multifork replication revealed an up to 30% S10 dosage reduction associated with its relocation that closely correlated with fitness alterations. Hence, the impact of S10 location goes beyond a growth optimization strategy during feast periods. RP location may be important during the whole life cycle of this pathogen. PMID:28246358

  20. Muscle atrophy

    MedlinePlus

    ... damage caused by injury, diabetes, toxins, or alcohol Polio ( poliomyelitis ) Spinal cord injury Although people can adapt to ... Guillain-Barré syndrome Hypotonia Muscle cramps Muscular dystrophy Polio Review Date 1/5/2016 Updated by: Joseph ...

  1. Getting Muscles

    MedlinePlus

    ... muscular as a superhero or your favorite professional athlete? Well, the big muscles you're thinking about ... Superheroes, of course, aren't real, and professional athletes are grownups, whose bodies are different from kids' ...

  2. Muscle twitching

    MedlinePlus

    ... patient with neurologic disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: ... Selcen D. Muscle diseases. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: ...

  3. FUENTES Infrarrojas EN 2.2 lim EN la Region Asociada AL GLOBULO ORI-1-2

    NASA Astrophysics Data System (ADS)

    Cruz-Gonzalez, J.; Carrasco, L.; Ramos, M. P.

    1987-05-01

    Se ha mapeado en el cercano infrarrojo a 2.2 micras, una región de 2 x 5 minutos de arco asociada al glóbulo ORI-I-2. Se ha detectado emisión infrarroja de fuentes puntuales y emisión extendida de bajo brillo superficial. Se discute la asociación de fuentes de 2.2 micras con la emisión detectada en IRAS y en moléculas de radio frecuencias.

  4. Effect of congenital blindness on EMG activity of the facial muscles.

    PubMed

    Tosello, D O; Vitti, M; Siéssere, S; Santos, C M; Verri, E D; Hallak, J E C; Semprini, M; Cecilio, F A; Regalo, S C H

    2008-03-01

    The aim of this work was to analyze electromyographically the facial muscles: orbicularis oris (upper and lower fascicles), orbicularis oculi (right and left lateral portions) and frontal, in blind and clinically normal (control) individuals, in various clinical conditions. Electromyographic averages of all data collected were normalized by maximal voluntary contraction of the studied muscles and statistical analysis was performed by Student's t test, using "Statistical Package for the Social Sciences" software--SPSS 12.0 (Chicago, IL). It was found that electromyographic alterations occur in the facial musculature that influences facial expressions of individuals. Results for the orbicularis oris muscle demonstrated that myoelectric activity among blind and control subjects was greater for the control group at muscular rest, blowing, and in labial projection. Electromyographic analysis of the orbicularis oculi among blind and control subjects in three clinical conditions studied demonstrated that activity was greater for the control group at muscular rest, blinking, and forced blinking. For the frontal muscles were demonstrated that electromyographic activity was greater for blind individuals. These data suggest the influence of congenital blindness on muscular development, including alterations in electromyographic activity of skin musculature in individuals with visual impairment.

  5. X-Raying the Beating Heart of a Newborn Star: Rotational Modulation of High-Energy Radiation from V1647 Ori

    NASA Technical Reports Server (NTRS)

    Hamaguchi, Kenji; Grosso, Nicolas; Kastner, Joel H.; Weintraub, David A.; Richmond, Michael; Petre, Robert; Teets, William K.; Principe, David

    2012-01-01

    We report a periodicity of approx.1 day in the highly elevated X-ray emission from the protostar V1647 Ori during its two recent multiple-year outbursts of mass accretion. This periodicity is indicative of protostellar rotation at near-breakup speed. Modeling of the phased X-ray light curve indicates the high-temperature ( 50 MK), X-ray-emitting plasma, which is most likely heated by accretion-induced magnetic reconnection, resides in dense ( 5 1010 cm.3), pancake-shaped magnetic footprints where the accretion stream feeds the newborn star. The sustained X-ray periodicity of V1647 Ori demonstrates that such protostellar magnetospheric accretion configurations can be stable over timescales of years. Subject headings: stars: formation stars: individual (V1647 Ori) stars: pre-main sequence X-rays: stars

  6. An origin of transfer (oriT) on the conjugative element pRS01 from Lactococcus lactis subsp. lactis ML3.

    PubMed

    Mills, D A; Phister, T G; Dunny, G M; McKay, L L

    1998-04-01

    Previous analysis of the Tra1 region of the conjugative element pRS01 from Lactococcus lactis subsp. lactis ML3 suggested that an origin of transfer (oriT) was present. Deletion derivatives of this cloned Tra1 region were assayed for mobilization in the presence of the wild-type pRS01 element in trans. The pRS01 oriT was localized to a 446-nucleotide segment in the intergenic region between open reading frames ltrD and ltrE. Sequence analysis of this region revealed a cluster of direct and inverted repeat structures characteristic of oriT regions associated with other conjugative systems.

  7. First BVR light curves and preliminary results of a recently discovered W UMa-type binary: V1848 Ori

    NASA Astrophysics Data System (ADS)

    Kriwattanawong, W.; Poojon, P.

    2014-04-01

    First complete photometric light curves of a recently discovered contact binary, V1848 Ori, are presented. BVR imaging data were used to derive photometric solutions, using Wilson-Devinney code. We discovered that this system is a weak-contact binary, with a fillout factor of f = 13.14%(±1.44%). Preliminary results showed that V1848 Ori is an A-type W UMa system, with a mass ratio of q = 0.7615. The more massive component was found about 400 K hotter than the other one. This system has varied from W-type to A-type during the last decade. According to the preliminary physical parameters, the weak-contact configuration of this system, with the mass ratio close to unity, and no sign of long-term orbital period change yet, is unlikely to be broken. The contact configuration is expected to be maintained and become deeper or not, depending on effect of the AML mechanism.

  8. Influence of pre-orthodontic trainer treatment on the perioral and masticatory muscles in patients with Class II division 1 malocclusion.

    PubMed

    Uysal, Tancan; Yagci, Ahmet; Kara, Sadik; Okkesim, Sukru

    2012-02-01

    The aim of this follow-up study was to evaluate the effects of Pre-Orthodontic Trainer (POT) appliance on the anterior temporal, mental, orbicularis oris, and masseter muscles through electromyography (EMG) evaluations in subjects with Class II division 1 malocclusion and incompetent lips. Twenty patients (mean age: 9.8 ± 2.2 years) with a Class II division 1 malocclusion were treated with POT (Myofunctional Research Co., Queensland, Australia). A group of 15 subjects (mean age: 9.2 ± 0.9 years) with untreated Class II division 1 malocclusions was used as a control. EMG recordings of treatment group were taken at the beginning and at the end of the POT therapy (mean treatment period: 7.43 ± 1.06 months). Follow-up records of the control group were taken after 8 months of the first records. Recordings were taken during different oral functions: clenching, sucking, and swallowing. Statistical analyses were undertaken with Wilcoxon and Mann-Whitney U-tests. During the POT treatment, activity of anterior temporal, mental, and masseter muscles was decreased and orbicularis oris activity was increased during clenching and these differences were found statistically significant when compared to control. Orbicularis oris activity during sucking was increased in the treatment group (P < 0.05). In the control group, significant changes were determined for anterior temporal (P < 0.05) and masseter (P < 0.01) muscle at clenching and orbicularis oris (P < 0.05) muscle at swallowing during observation period. Present findings indicated that treatment with POT appliance showed a positive influence on the masticatory and perioral musculature.

  9. Muscle strain (image)

    MedlinePlus

    A muscle strain is the stretching or tearing of muscle fibers. A muscle strain can be caused by sports, exercise, a ... something that is too heavy. Symptoms of a muscle strain include pain, tightness, swelling, tenderness, and the ...

  10. The Ionization Structure of Sharpless 2-264: Multiwavelength Observations of the λ Ori H II Region

    NASA Astrophysics Data System (ADS)

    Sahan, M.; Haffner, L. M.

    2016-06-01

    We present velocity-resolved maps taken with the Wisconsin H-Alpha Mapper (WHAM) in Hα, [S ii] λ 6716, and [N ii] λ 6583 around the well-known O8 III star λ Ori A (HD 36861) ({\\ell }=185^\\circ to 205^\\circ ,b=-24^\\circ to -1^\\circ ). The integrated intensity ({v}{{LSR}}=-80 to +80 km s-1), {I}{{H}α }, within WHAM’s one-degree beams varies from ˜190 R near the center to ˜10 R on the periphery of the nebula where it becomes comparable to foreground and/or background emission in this complex region. Intensity ratios for [N ii]/Hα and [S ii]/Hα average 0.28 and 0.35, respectively. In both ratios, higher values are found preferentially at larger radii from λ Ori, although the behavior of [N ii]/Hα is complicated near the edges of the nebula. The [S ii]/[N ii] intensity ratio ranges from ˜0.5 to ˜1.0, with the value increasing toward larger radii (and lower Hα intensities). Variations of the [S ii]/Hα, [N ii]/Hα, and [S ii]/[N ii] line ratios in this diffuse region show some similar trends to those seen in the warm ionized medium (WIM) but with generally lower metal-line ratios. As with the WIM, the trends are driven by changes in the underlying physical parameters, most notably the ionization states and gas temperature. To investigate which cause might be dominant in this region, we use these extremely high signal-to-noise observations to construct a map of temperature and non-thermal velocity throughout the nebula. Using the line widths of Hα and [S ii], we separate thermal and non-thermal components and find spatial trends of these parameters within the nebula. Ion temperatures range between 4000 and 8000 K throughout the nebula. The non-thermal velocity map reveals a decrease in velocity from about 10 to 5 km s-1 from the center to the edge of the lower half of the H ii region. In addition to using the widths as a measure of temperature, we also use the variation in [N ii]/Hα to estimate electron temperature. The results obtained from this

  11. Spectroscopy of the M Supergiant α Ori in the 1 2.5 μm Region

    NASA Astrophysics Data System (ADS)

    Lundqvist, Martin; Wahlgren, Glenn

    The study of elemental abundances in cool stars via atomic lines in the optical region is made di.cult by stellar molecular absorption. At infrared wavelengths this problem is diminished, but ground-based observations suffer from absorption by the earth’s atmosphere. Fortunately, there are spectral windows through which we can observe. We have explored several such windows in the spectral region from 1 2.5 μm, coinciding with the wavelength domain of the new VLT instrument CRIRES, for atomic lines suitable for the study of cool luminous stars, in particular α Ori (M2Iab). We present preliminary results from this search along with our first results on abundances of iron and the weak s-process elements Sr, Y, Zr.

  12. Evolution of the muscles of facial expression in a monogamous ape: evaluating the relative influences of ecological and phylogenetic factors in hylobatids.

    PubMed

    Burrows, Anne M; Diogo, Rui; Waller, Bridget M; Bonar, Christopher J; Liebal, Katja

    2011-04-01

    Facial expression is a communication mode produced by facial (mimetic) musculature. Hylobatids (gibbons and siamangs) have a poorly documented facial display repertoire and little is known about their facial musculature. These lesser apes represent an opportunity to test hypotheses related to the evolution of primate facial musculature as they are the only hominoid with a monogamous social structure, and thus live in very small groups. Primate species living in large groups with numerous social relationships, such as chimpanzees and rhesus macaques, have been shown to have a complex facial display repertoire and a high number of discrete facial muscles. The present study was designed to examine the relative influence of social structure and phylogeny on facial musculature evolution by comparing facial musculature complexity among hylobatids, chimpanzees, and rhesus macaques. Four faces were dissected from four hylobatid species. Morphology, attachments, three-dimensional relationships, and variation among specimens were noted and compared to rhesus macaques and chimpanzees. Microanatomical characteristics of the orbicularis oris muscle were also compared. Facial muscles of hylobatids were generally gracile and less complex than both the rhesus macaque and chimpanzee. Microanatomically, the orbicularis oris muscle of hylobatids was relatively loosely packed with muscle fibers. These results indicate that environmental and social factors may have been important in determining morphology and complexity of facial musculature in the less social hylobatids and that they may not have experienced as strong selection pressure for mimetic muscle complexity as other, more social primates.

  13. MULTIWAVELENGTH OBSERVATIONS OF V2775 Ori, AN OUTBURSTING PROTOSTAR IN L 1641: EXPLORING THE EDGE OF THE FU ORIONIS REGIME

    SciTech Connect

    Fischer, William J.; Megeath, S. Thomas; Kounkel, Marina; Tobin, John J.; Stutz, Amelia M.; Henning, Thomas; Ali, Babar; Stanke, Thomas; Osorio, Mayra; Wilson, T. L.

    2012-09-01

    Individual outbursting young stars are important laboratories for studying the physics of episodic accretion and the extent to which this phenomenon can explain the luminosity distribution of protostars. We present new and archival data for V2775 Ori (HOPS 223), a protostar in the L 1641 region of the Orion molecular clouds that was discovered by Caratti o Garatti et al. to have recently undergone an order-of-magnitude increase in luminosity. Our near-infrared spectra of the source have strong blueshifted He I {lambda}10830 absorption, strong H{sub 2}O and CO absorption, and no H I emission, all typical of FU Orionis sources. With data from the Infrared Telescope Facility, the Two Micron All Sky Survey, the Hubble Space Telescope, Spitzer, the Wide-field Infrared Survey Explorer, Herschel, and the Atacama Pathfinder Experiment that span from 1 to 70 {mu}m pre-outburst and from 1 to 870 {mu}m post-outburst, we estimate that the outburst began between 2005 April and 2007 March. We also model the pre- and post-outburst spectral energy distributions of the source, finding it to be in the late stages of accreting its envelope with a disk-to-star accretion rate that increased from {approx}2 Multiplication-Sign 10{sup -6} M{sub Sun} yr{sup -1} to {approx}10{sup -5} M{sub Sun} yr{sup -1} during the outburst. The post-outburst luminosity at the epoch of the FU Orionis-like near-IR spectra is 28 L{sub Sun }, making V2775 Ori the least luminous documented FU Orionis outburster with a protostellar envelope. The existence of low-luminosity outbursts supports the notion that a range of episiodic accretion phenomena can partially explain the observed spread in protostellar luminosities.

  14. The fluid and electrolyte balance of New Zealand European and Māori/Pacific Island athletes: An observational study.

    PubMed

    McLean, Andrew; Brown, Rachel Clare; Black, Katherine Elizabeth

    2016-01-01

    Observational research on professional athletes from the USA suggests differences may exist in sweat sodium loss based on ethnic differences. The New Zealand (NZ) sporting population is mainly of European or Māori/Pacific Island origin. Therefore, this study aimed to describe the fluid-electrolyte balance of athletes by ethnicity. A total of 20 Māori/Pacific Islanders (MP; body mass 100.97 ± 13.05 kg) and 29 NZ European (NZE; body mass 89.11 ± 11.56 kg) elite male athletes were recruited. Sweat rates were determined by body mass change during a 1-h spin cycle exercise session, during which fluid intakes and heart rate were recorded. Sweat samples were analysed for sodium concentration. Mean ± SD sweat sodium concentrations were 73.4 ± 27.2 mmol·L(-1) and 55.5 ± 26.8 mmol·L(-1) for the MP and NZE groups, respectively (p = 0.070). Sweat rate was 0.93 ± 0.26 L·h(-1) for the MP group and 0.89 ± 0.33 L·h(-1) for the NZE group (p = 0.357). Fluid intake was 1.05 ± 0.48 L and 0.93 ± 0.49 L for MP and NZE, respectively (p = 0.395). Half of the MP group gained weight during the exercise session compared to 37% of the NZE group. Pre-exercise urine specific gravity was significantly lower amongst the NZE group (1.016 ± 0.009 g mL(-1)) than the MP group (1.024 ± 0.008 g mL(-1)) p = 0.001. There was no significant difference in heart rate between the groups, p = 0.082. Hydration practices of athletes in NZ may differ by ethnicity, and this may highlight the need for more targeted education by ethnicity.

  15. The 2005 Accretion Outburst in V1118 Ori: Evidence for A Spectral Change in X-rays

    NASA Astrophysics Data System (ADS)

    Audard, M.; Güdel, M.; Skinner, S. L.; Briggs, K. R.; Walter, F. M.; Stringfellow, G.; Hamilton, R. T.; Guinan, E. F.

    2005-12-01

    We present results from our X-ray monitoring campaign of the 2005 accretion outburst in the young low-mass star V1118 Ori. Optical and near-infrared photometry are presented as well. The X-ray data from early 2005 indicate that the X-ray flux and luminosity varied within a factor of two only, and were similar to the pre-outburst values measured in a serendipitous observation in 2002. Similarly, the hydrogen column density showed no evidence for significant excursions from the pre-outburst value of a few times 1021 cm-2. However, we observed a spectral change from a dominant hot plasma ( ˜ 25 MK) in 2002 and in January 2005 to a cooler plasma ( ˜ 8 MK) in February and March 2005. We argue that the closing in of the accretion disk during the outburst disrupted the hot magnetic loops high in the corona, whereas the lower cooler loops were less affected and became the dominant coronal component. We acknowledge support by NASA through Chandra award DD5-6029X and through XMM-Newton award NNG05GI96G to Columbia University. The Chandra X-ray Observatory Center is operated by the Smithsonian Astrophysical Observatory for and on behalf of the NASA under contract NAS8-03060. Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. The PSI group acknowledges support from the Swiss National Science Foundation (grants 20-58827.99 and 20-66875.01). Stony Brook's participation in SMARTS is made possible by support from the offices of the Provost and the Vice President for Research. We thank J. Allyn Smith, P. McGehee, J. Espinoza, and D. Gonzalez for doing the observations with the SMARTS telescopes. We also thank H. Tannanbaum, N. Schartel, and the VLA TOO panel for granting time to observe V1118 Ori.

  16. Revisiting the rigidly rotating magnetosphere model for σ Ori E - II. Magnetic Doppler imaging, arbitrary field RRM, and light variability

    NASA Astrophysics Data System (ADS)

    Oksala, M. E.; Kochukhov, O.; Krtička, J.; Townsend, R. H. D.; Wade, G. A.; Prvák, M.; Mikulášek, Z.; Silvester, J.; Owocki, S. P.

    2015-08-01

    The initial success of the Rigidly Rotating Magnetosphere (RRM) model application to the B2Vp star σ Ori E by Townsend, Owocki & Groote triggered a renewed era of observational monitoring of this archetypal object. We utilize high-resolution spectropolarimetry and the magnetic Doppler imaging (MDI) technique to simultaneously determine the magnetic configuration, which is predominately dipolar, with a polar strength Bd = 7.3-7.8 kG and a smaller non-axisymmetric quadrupolar contribution, as well as the surface distribution of abundance of He, Fe, C, and Si. We describe a revised RRM model that now accepts an arbitrary surface magnetic field configuration, with the field topology from the MDI models used as input. The resulting synthetic H α emission and broad-band photometric observations generally agree with observations, however, several features are poorly fit. To explore the possibility of a photospheric contribution to the observed photometric variability, the MDI abundance maps were used to compute a synthetic photospheric light curve to determine the effect of the surface inhomogeneities. Including the computed photospheric brightness modulation fails to improve the agreement between the observed and computed photometry. We conclude that the discrepancies cannot be explained as an effect of inhomogeneous surface abundance. Analysis of the UV light variability shows good agreement between observed variability and computed light curves, supporting the accuracy of the photospheric light variation calculation. We thus conclude that significant additional physics is necessary for the RRM model to acceptably reproduce observations of not only σ Ori E, but also other similar stars with significant stellar wind-magnetic field interactions.

  17. Mobilization of Chimeric oriT Plasmids by F and R100-1: Role of Relaxosome Formation in Defining Plasmid Specificity

    PubMed Central

    Fekete, Richard A.; Frost, Laura S.

    2000-01-01

    Cleavage at the F plasmid nic site within the origin of transfer (oriT) requires the F-encoded proteins TraY and TraI and the host-encoded protein integration host factor in vitro. We confirm that F TraY, but not F TraM, is required for cleavage at nic in vivo. Chimeric plasmids were constructed which contained either the entire F or R100-1 oriT regions or various combinations of nic, TraY, and TraM binding sites, in addition to the traM gene. The efficiency of cleavage at nic and the frequency of mobilization were assayed in the presence of F or R100-1 plasmids. The ability of these chimeric plasmids to complement an F traM mutant or affect F transfer via negative dominance was also measured using transfer efficiency assays. In cases where cleavage at nic was detected, R100-1 TraI was not sensitive to the two-base difference in sequence immediately downstream of nic, while F TraI was specific for the F sequence. Plasmid transfer was detected only when TraM was able to bind to its cognate sites within oriT. High-affinity binding of TraY in cis to oriT allowed detection of cleavage at nic but was not required for efficient mobilization. Taken together, our results suggest that stable relaxosomes, consisting of TraI, -M, and -Y bound to oriT are preferentially targeted to the transfer apparatus (transferosome). PMID:10869081

  18. A Functional oriT in the Ptw Plasmid of Burkholderia cenocepacia Can Be Recognized by the R388 Relaxase TrwC

    PubMed Central

    Fernández-González, Esther; Bakioui, Sawsane; Gomes, Margarida C.; O'Callaghan, David; Vergunst, Annette C.; Sangari, Félix J.; Llosa, Matxalen

    2016-01-01

    Burkholderia cenocepacia is both a plant pathogen and the cause of serious opportunistic infections, particularly in cystic fibrosis patients. B. cenocepacia K56-2 harbors a native plasmid named Ptw for its involvement in the Plant Tissue Watersoaking phenotype. Ptw has also been reported to be important for survival in human cells. Interestingly, the presence of PtwC, a homolog of the conjugative relaxase TrwC of plasmid R388, suggests a possible function for Ptw in conjugative DNA transfer. The ptw region includes Type IV Secretion System genes related to those of the F plasmid. However, genes in the adjacent region shared stronger homology with the R388 genes involved in conjugative DNA metabolism. This region included the putative relaxase ptwC, a putative coupling protein and accessory nicking protein, and a DNA segment with high number of inverted repeats and elevated AT content, suggesting a possible oriT. Although we were unable to detect conjugative transfer of the Ptw resident plasmid, we detected conjugal mobilization of a co-resident plasmid containing the ptw region homologous to R388, demonstrating the cloned ptw region contains an oriT. A similar plasmid lacking ptwC could not be mobilized, suggesting that the putative relaxase PtwC must act in cis on its oriT. Remarkably, we also detected mobilization of a plasmid containing the Ptw oriT by the R388 relaxase TrwC, yet we could not detect PtwC-mediated mobilization of an R388 oriT-containing plasmid. Our data unambiguously show that the Ptw plasmid harbors DNA transfer functions, and suggests the Ptw plasmid may play a dual role in horizontal DNA transfer and eukaryotic infection. PMID:27200362

  19. Muscle strain treatment

    MedlinePlus

    Treatment - muscle strain ... Question: How do you treat a muscle strain ? Answer: Rest the strained muscle and apply ice for the first few days after the injury. Anti-inflammatory medicines or acetaminophen ( ...

  20. Eye muscle repair - discharge

    MedlinePlus

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  1. Otariodibacter oris gen. nov., sp. nov., a member of the family Pasteurellaceae isolated from the oral cavity of pinnipeds.

    PubMed

    Hansen, Mie Johanne; Bertelsen, Mads Frost; Christensen, Henrik; Bojesen, Anders Miki; Bisgaard, Magne

    2012-11-01

    A total of 27 bacterial isolates from California sea lions and a walrus tentatively classified within the family Pasteurellaceae was further characterized by genotypic and phenotypic tests. Phylogenetic analysis of partial 16S rRNA and rpoB gene sequences showed that the isolates investigated formed a monophyletic group, tentatively designated Bisgaard taxon 57. According to 16S rRNA gene sequences, the most closely related species with a validly published name was Bisgaardia hudsonensis and the most closely related species based on rpoB sequence comparison was Pasteurella multocida subsp. multocida; highest similarities between the isolates and the type strains of B. hudsonensis and P. multocida subsp. multocida were 95.0 and 88.2%. respectively. All isolates of Bisgaard taxon 57 exhibit the phenotypic characters of the family Pasteurellaceae. Members of Bisgaard taxon 57 can be separated from existing genera of the Pasteurellaceae by the following tests: positive reactions for catalase, oxidase, Voges-Proskauer and indole; no X- or V-factor dependency; and acid production from L-arabinose (slow), L-fucose, maltose and trehalose, but not from dulcitol, D-mannitol, D-mannose or sucrose. The main fatty acids of Bisgaard taxon 57 (CCUG 59994(T)) are C(14:0), C(16:0), C(16:1)ω7c and the summed feature C(14:0) 3-OH/iso-C(16:1) I. This fatty acid profile is characteristic of members of the Pasteurellaceae. The quinone profile of Bisgaard taxon 57 (DSM 23800(T)) was similar to that of other genera in the Pasteurellaceae. The DNA G+C content of strain Baika1(T) is 36.2 mol%, which is at the lower end of the range for members of the family Pasteurellaceae. On the basis of both phylogenetic and phenotypic evidence, it is proposed that members of Bisgaard taxon 57 should be classified as representatives of a novel species in a new genus, Otariodibacter oris gen. nov., sp. nov. The type strain of Otariodibacter oris is Baika1(T) (=CCUG 59994(T)=DSM 23800(T)), which was

  2. The EXOTIME Monitoring Program Discovers Substellar Companion Candidates around the Rapidly Pulsating Subdwarf B Stars V1636 Ori and DW Lyn

    NASA Astrophysics Data System (ADS)

    Schuh, S.; Silvotti, R.; Lutz, R.; Kim, S.-L.; Exotime Collaboration

    2014-04-01

    The EXOTIME monitoring program has discovered sub-stellar companion candidates around the rapidly pulsating subdwarf B stars V1636 Ori and DW Lyn using the timing method. Here we motivate our continuing search, and refer to descriptions of the photometric data collected, the data analysis and the characteristics of the O-C diagrams obtained. We also discuss our on-going efforts to consolidate the candidate discoveries with additional simulations and confirm them with independent methods.

  3. A Disulfide Bond-forming Machine Is Linked to the Sortase-mediated Pilus Assembly Pathway in the Gram-positive Bacterium Actinomyces oris*

    PubMed Central

    Reardon-Robinson, Melissa E.; Osipiuk, Jerzy; Chang, Chungyu; Wu, Chenggang; Jooya, Neda; Joachimiak, Andrzej; Das, Asis; Ton-That, Hung

    2015-01-01

    Export of cell surface pilins in Gram-positive bacteria likely occurs by the translocation of unfolded precursor polypeptides; however, how the unfolded pilins gain their native conformation is presently unknown. Here, we present physiological studies to demonstrate that the FimA pilin of Actinomyces oris contains two disulfide bonds. Alanine substitution of cysteine residues forming the C-terminal disulfide bridge abrogates pilus assembly, in turn eliminating biofilm formation and polymicrobial interaction. Transposon mutagenesis of A. oris yielded a mutant defective in adherence to Streptococcus oralis, and revealed the essential role of a vitamin K epoxide reductase (VKOR) gene in pilus assembly. Targeted deletion of vkor results in the same defects, which are rescued by ectopic expression of VKOR, but not a mutant containing an alanine substitution in its conserved CXXC motif. Depletion of mdbA, which encodes a membrane-bound thiol-disulfide oxidoreductase, abrogates pilus assembly and alters cell morphology. Remarkably, overexpression of MdbA or a counterpart from Corynebacterium diphtheriae, rescues the Δvkor mutant. By alkylation assays, we demonstrate that VKOR is required for MdbA reoxidation. Furthermore, crystallographic studies reveal that A. oris MdbA harbors a thioredoxin-like fold with the conserved CXXC active site. Consistently, each MdbA enzyme catalyzes proper disulfide bond formation within FimA in vitro that requires the catalytic CXXC motif. Because the majority of signal peptide-containing proteins encoded by A. oris possess multiple Cys residues, we propose that MdbA and VKOR constitute a major folding machine for the secretome of this organism. This oxidative protein folding pathway may be a common feature in Actinobacteria. PMID:26170452

  4. Exploring occupation roles of hospice family caregivers from Māori, Chinese and Tongan ethnic backgrounds living in New Zealand.

    PubMed

    Angelo, Jennifer; Wilson, Linda

    2014-06-01

    A major challenge to occupational therapists working in palliative care is determining the best ways to help family caregivers who are caring for family members. The purpose of this study was to explore palliative caregiver occupations among Māori, Chinese and Tongan ethnicities. Six informants participated, one woman and one man from each ethnic group. In each of their homes, informants were asked to discuss what it was like caring for their dying family member. The occupational themes resulting from these interviews were food preparation, spirituality and family gathering. Therapists need to be aware of the differences in how people care for family members within their ethnicity. Implications are that occupational therapists can help families identify activities important to them within the main occupational themes: different types of foods and their preparations, various ways to express spirituality and how families gather together members of their extended family. Further, clinicians need to take on the role of a "not-knowing" but curious health-care provider in order to meet the needs of caregivers. The limitation was the small number of participants who all lived in one geographic area. Future studies should include a wider group of ethnicities.

  5. The Chandra Delta Ori Large Project: Occultation Measurements of the Shocked Gas tn the Nearest Eclipsing O-Star Binary

    NASA Technical Reports Server (NTRS)

    Corcoran, Michael F.; Nichols, Joy; Naze, Yael; Rauw, Gregor; Pollock, Andrew; Moffat, Anthony; Richardson, Noel; Evans, Nancy; Hamaguchi, Kenji; Oskinova, Lida; Hamann, W. -R.; Gull, Ted; Ignace, Rico; Hole, Tabetha; Iping, Rosina; Walborn, Nolan; Hoffman, Jennifer; Lomax, Jamie; Waldron, Wayne; Owocki, Stan; Maiz-Apellaniz, Jesus; Leutenegger, Maurice; Hole, Tabetha; Gayley, Ken; Russell, Chris

    2013-01-01

    Delta Ori is the nearest massive, single-lined eclipsing binary (O9.5 II + B0.5III). As such it serves as a fundamental calibrator of the mass-radius-luminosity relation in the upper HR diagram. It is also the only eclipsing O-type binary system which is bright enough to be observable with the CHANDRA gratings in a reasonable exposure. Studies of resolved X-ray line complexes provide tracers of wind mass loss rate and clumpiness; occultation by the X-ray dark companion of the line emitting region can provide direct spatial information on the location of the X-ray emitting gas produced by shocks embedded in the wind of the primary star. We obtained phase-resolved spectra with Chandra in order to determine the level of phase-dependent vs. secular variability in the shocked wind. Along with the Chandra observations we obtained simultaneous photometry from space with the Canadian MOST satellite to help understand the relation between X-ray and photospheric variability.

  6. Relational Resilience in Māori, Pacific, and European Sole Parent Families: From Theory and Research to Social Policy.

    PubMed

    Waldegrave, Charles; King, Peter; Maniapoto, Maria; Tamasese, Taimalieutu Kiwi; Parsons, Tafaoimalo Loudeen; Sullivan, Ginny

    2016-12-01

    This study reports findings and policy recommendations from a research project that applied a relational resilience framework to a study of 60 sole parent families in New Zealand, with approximately equal numbers of Māori, Pacific, and European (White) participants. The sole parent families involved were already known to be resilient and the study focused on identifying the relationships and strategies underlying the achievement and maintenance of their resilience. The study was carried out to provide an evidence base for the development and implementation of policies and interventions to both support sole parent families who have achieved resilience and assist those who struggle to do so. The three populations shared many similarities in their pathways to becoming sole parents and the challenges they faced as sole parents. The coping strategies underlying their demonstrated resilience were also broadly similar, but the ways in which they were carried out did vary in a manner that particularly reflected cultural practices in terms of their reliance upon extended family-based support or support from outside the family. The commonalities support the appropriateness of the common conceptual framework used, whereas the differences underline the importance of developing nuanced policy responses that take into account cultural differences between the various populations to which policy initiatives are directed.

  7. Muscle shape consistency and muscle volume prediction of thigh muscles.

    PubMed

    Mersmann, F; Bohm, S; Schroll, A; Boeth, H; Duda, G; Arampatzis, A

    2015-04-01

    The present study investigated the applicability of a muscle volume prediction method using only the muscle length (L(M)), the maximum anatomical cross-sectional area (ACSA(max)), and a muscle-specific shape factor (p) on the quadriceps vastii. L(M), ACSA(max), muscle volume, and p were obtained from magnetic resonance images of the vastus intermedius (VI), lateralis (VL), and medialis (VM) of female (n = 20) and male (n = 17) volleyball athletes. The average p was used to predict muscle volumes (V(p)) using the equation V(p)  = p × ACSA(max)  × L(M). Although there were significant differences in the muscle dimensions between male and female athletes, p was similar and on average 0.582, 0.658, 0.543 for the VI, VL, and VM, respectively. The position of ACSA(max) showed low variability and was at 57%, 60%, and 81% of the thigh length for VI, VL, and VM. Further, there were no significant differences between measured and predicted muscle volumes with root mean square differences of 5-8%. These results suggest that the muscle shape of the quadriceps vastii is independent of muscle dimensions or sex and that the prediction method could be sensitive enough to detect changes in muscle volume related to degeneration, atrophy, or hypertrophy.

  8. Whakawhiti Kōrero, a Method for the Development of a Cultural Assessment Tool, Te Waka Kuaka, in Māori Traumatic Brain Injury

    PubMed Central

    Elder, Hinemoa; Kersten, Paula

    2015-01-01

    The importance of tools for the measurement of outcomes and needs in traumatic brain injury is well recognised. The development of tools for these injuries in indigenous communities has been limited despite the well-documented disparity of brain injury. The wairua theory of traumatic brain injury (TBI) in Māori proposes that a culturally defined injury occurs in tandem with the physical injury. A cultural response is therefore indicated. This research investigates a Māori method used in the development of cultural needs assessment tool designed to further examine needs associated with the culturally determined injury and in preparation for formal validation. Whakawhiti kōrero is a method used to develop better statements in the development of the assessment tool. Four wānanga (traditional fora) were held including one with whānau (extended family) with experience of traumatic brain injury. The approach was well received. A final version, Te Waka Kuaka, is now ready for validation. Whakawhiti kōrero is an indigenous method used in the development of cultural needs assessment tool in Māori traumatic brain injury. This method is likely to have wider applicability, such as Mental Health and Addictions Services, to ensure robust process of outcome measure and needs assessment development. PMID:26576070

  9. The past photometric history of the FU Ori-type young eruptive star 2MASS J06593158-0405277 = V960 Mon

    NASA Astrophysics Data System (ADS)

    Jurdana-Šepić, Rajka; Munari, Ulisse

    2016-02-01

    The known FU Ori-type young eruptive stars are exceedingly rare (a dozen or so confirmed objects) and 2MASS J06593158-0405277, with its 2014 outburst, is likely the latest addition to the family. All members have displayed just one such eruption in their recorded history, an event lasting for decades. To test the FU Ori nature of 2MASS J06593158-0405277, we have reconstructed its photometric history by measuring its brightness on Harvard photographic plates spanning the time interval 1899-1989. No previous large amplitude eruption similar to that initiated in 2014 has been found, as in bona fide FU Ori-type objects. The median value of the brightness in quiescence of 2MASS J06593158-0405277 is B = 15.5, with the time interval 1935-1950 characterized by a large variability (∼ 1 mag amplitude) that contrasts with the remarkable photometric stability displayed at later epochs. The variability during 1935-1950 can either be ascribed to some T Tau like activity of 2MASS J06593158-0405277 itself or to the also young and fainter star 2MASS J06593168-0405224 that lies 5 arcsec to the North and forms an unresolved pair at the astrometric scale of Harvard photographic plates.

  10. Anatomy research of nasolabial muscle structure in fetus with cleft lip: an iodine staining technique based on microcomputed tomography.

    PubMed

    Wu, Jiajun; Yin, Ningbei

    2014-05-01

    A thorough knowledge of the anatomic structure of the orbicularis oris of the upper lip and the nasalis in fetus with cleft lip is the key for the success of cleft lip repair. To understand the anatomic structure of the muscles of nasolabial region in fetus with cleft lip, the nasolabial tissues in 4 aborted fetuses with cleft lip were soaked for 7 days with iodine solution (Lugol solution of 3.75%) and were given micro-computed tomography. After the iodine solution permeated into the soft tissues, a good contrast was showed between muscle fibers and other fibrillar connective tissues. Through the observation of the obtained images, we found that most orbicularis oris fibers gathered into bundles with clear outline and only had slight deformation and displacement on the health side of the cleft of the unilateral incomplete cleft lip; however, in the lateral cleft, the muscle fibers not only had deformation and displacement but also were immature, disorganized, and not gathered into bundles. After being restored in Digital Imaging and Communications in Medicine format, the obtained images were then transferred into Materialise's interactive medical image control system, edited, and reconstructed into three-dimensional models. The models clearly showed the spatial relationship between the muscular tissues of the nasolabial region and the nasolabial outline in fetus with cleft lip.

  11. Motor responses of muscles supplied by cranial nerves to subthalamic nucleus deep brain stimuli.

    PubMed

    Costa, João; Valls-Solé, Josep; Valldeoriola, Francesc; Rumià, Jordi; Tolosa, Eduardo

    2007-01-01

    The distribution of human corticobulbar motor excitatory and inhibitory output is not fully understood. In particular, it is unclear whether the pattern of innervation is the same for upper and lower facial muscles, and what is the motor cortical area giving rise to such innervation. We used electrodes implanted in the subthalamic nucleus (STN) in patients with Parkinson's disease to activate motor tracts at a subcortical level. We examined the excitatory and inhibitory effects of unilateral single STN deep brain stimulation (sSTN-DBS) in 14 patients by taking recordings from facial, cervical and upper limb muscles on both sides. We measured the latency and amplitude of the motor-evoked potentials (MEPs), and the latency and duration of the silent periods, and compared ipsilateral with contralateral responses and responses obtained in different muscles. Unilateral sSTN-DBS induced strictly contralateral MEPs in the trapezius, deltoid, biceps and thenar muscles. The same stimulus always induced bilateral MEPs in the orbicularis oculi, orbicularis oris, masseter and sternocleidomastoid at a mean latency in the range 6.0-9.1 ms. MEP latencies in the orbicularis oculi and orbicularis oris were significantly longer than in the masseter and sternocleidomastoid (P < 0.01). A short latency small action potential was recorded in the ipsilateral orbicularis oculi that was likely generated by activation of extraocular muscles. During sustained voluntary muscle contraction, a silent period was recorded at similar onset latency on both sides. This period was significantly shorter in orbicularis oculi than in masseter, and in the ipsilateral side for both muscles (P < 0.01). sSTN-DBS is able to activate the descending projecting fibres in the corticobulbar tract eliciting bilateral MEPs and silent periods in facial and cranial muscles. This suggests that fibres to both ipsi- and contralateral motor nuclei descend together at the level of the STN. These findings are relevant in

  12. Muscle Weakness

    PubMed Central

    Al Kaissi, Ali; Ryabykh, Sergey; Ochirova, Polina; Kenis, Vladimir; Hofstätter, Jochen G.; Grill, Franz; Ganger, Rudolf; Kircher, Susanne Gerit

    2017-01-01

    Marked ligamentous hyperlaxity and muscle weakness/wasting associated with awkward gait are the main deficits confused with the diagnosis of myopathy. Seven children (6 boys and 1 girl with an average age of 8 years) were referred to our department because of diverse forms of skeletal abnormalities. No definitive diagnosis was made, and all underwent a series of sophisticated investigations in other institutes in favor of myopathy. We applied our methodology through the clinical and radiographic phenotypes followed by targeted genotypic confirmation. Three children (2 boys and 1 girl) were compatible with the diagnosis of progressive pseudorheumatoid chondrodysplasia. The genetic mutation was correlated with the WISP 3 gene actively expressed by articular chondrocytes and located on chromosome 6. Klinefelter syndrome was the diagnosis in 2 boys. Karyotyping confirmed 47,XXY (aneuploidy of Klinefelter syndrome). And 2 boys were finally diagnosed with Morquio syndrome (MPS type IV A) as both showed missense mutations in the N-acetylgalactosamine-sulfate sulfatase gene. Misdiagnosis can lead to the initiation of a long list of sophisticated investigations. PMID:28210640

  13. Adhesion of Streptococcus mitis and Actinomyces oris in co-culture to machined and anodized titanium surfaces as affected by atmosphere and pH

    PubMed Central

    2013-01-01

    Background With the rising demand for osseointegrated titanium implants for replacing missing teeth, often in patients with a history of periodontitis, implant-related infections have become an issue of growing concern. Novel methods for treating and preventing implant-associated infections are urgently needed. The aim of this study was to investigate if different pH, atmosphere and surface properties could restrict bacterial adhesion to titanium surfaces used in dental implants. Methods Titanium discs with machined or anodized (TiUnite™) surface were incubated with a co-culture of Streptococcus mitis and Actinomyces oris (early colonizers of oral surfaces) at pH 5.0, 7.0 and 9.0 at aerobic or anaerobic atmosphere. The adhesion was analysed by counting colony forming (CFU) units on agar and by confocal laser scanning microscopy (CLSM). Results The CFU analysis showed that a pH of 5.0 was found to significantly decrease the adhesion of S. mitis, and an aerobic atmosphere, the adhesion of A. oris. S. mitis was found in significantly less amounts on the anodized surface than the machined surface, while A. oris was found in equal amounts on both surfaces. The CLSM analysis confirmed the results from the CFU count and provided additional information on how the two oral commensal species adhered to the surfaces: mainly in dispersed clusters oriented with the groves of the machined surface and the pores of the anodized surface. Conclusions Bacterial adhesion by S. mitis and A. oris can be restricted by acidic pH and aerobic atmosphere. The anodized surface reduced the adhesion of S. mitis compared to the machined surface; while A. oris adhered equally well to the pores of the anodized surface and to the grooves of the machined surface. It is difficult to transfer these results directly into a clinical situation. However, it is worth further investigating these findings from an in vitro perspective, as well as clinically, to gain more knowledge of the effects acid pH and

  14. Reconditioning aging muscles.

    PubMed

    Kraus, H

    1978-06-01

    Weakness or stiffness of key posture muscles can cause much of the disability seen in elderly patients. Too much tension and too little exercise greatly increase the natural loss of muscular fitness with age. A systematic program of exercise, stressing relaxation and stretching of tight muscles and strenghthening of weak muscles, can improve physical fitness. The program must be tailored to the patient, starting with relaxation and gentle limbering exercises and proceeding ultimately to vigorous muscle-stretching exercises. Muscle aches and pain from tension and muscle imbalance are to be expected. Relaxation relieves tension pain, and strengthening weak muscles and stretching tight muscles will correct muscle imbalance. To prevent acute muscle spasm, the patient should avoid excessive exertion and increase exercise intensity gradually.

  15. The administration of Fructus Schisandrae attenuates dexamethasone-induced muscle atrophy in mice

    PubMed Central

    KIM, JOO WAN; KU, SAE-KWANG; HAN, MIN HO; KIM, KI YOUNG; KIM, SUNG GOO; KIM, GI-YOUNG; HWANG, HYE JIN; KIM, BYUNG WOO; KIM, CHEOL MIN; CHOI, YUNG HYUN

    2015-01-01

    In the present study, we aimed to determine whether ethanol extracts of Fructus Schisandrae (FS), the dried fruit of Schizandra chinensis Baillon, mitigates the development of dexamethasone-induced muscle atrophy. Adult SPF/VAT outbred CrljOri:CD1 (ICR) mice were either treated with dexamethasone to induce muscle atrophy. Some mice were treated with various concentrations of FS or oxymetholone, a 17α-alkylated anabolic-androgenic steroid. Muscle thickness and weight, calf muscle strength, and serum creatine and creatine kinase (CK) levels were then measured. The administration of FS attenuated the decrease in calf thickness, gastrocnemius muscle thickness, muscle strength and weight, fiber diameter and serum lactate dehydrogenase levels in the gastrocnemius muscle bundles which was induced by dexamethasone in a dose-dependent manner. Treatment with FS also prevented the dexamethasone-induced increase in serum creatine and creatine kinase levels, histopathological muscle fiber microvacuolation and fibrosis, and the immunoreactivity of muscle fibers for nitrotyrosine, 4-hydroxynonenal, inducible nitric oxide synthase and myostatin. In addition, the destruction of the gastrocnemius antioxidant defense system was also inhibited by the administration of FS in a dose-dependent manner. FS downregulated the mRNA expression of atrogin-1 and muscle RING-finger protein-1 (involved in muscle protein degradation), myostatin (a potent negative regulator of muscle growth) and sirtuin 1 (a representative inhibitor of muscle regeneration), but upregulated the mRNA expression of phosphatidylinositol 3-kinase, Akt1, adenosine A1 receptor and transient receptor potential cation channel subfamily V member 4, involved in muscle growth and the activation of protein synthesis. The overall effects of treatment with 500 mg/kg FS were comparable to those observed following treatment with 50 mg/kg oxymetholone. The results from the present study support the hypothesis that FS has a favorable

  16. Noma (cancrum oris): case report in a 4-year-old HIV-positive South African child.

    PubMed

    Naidoo, S; Chikte, U M

    2000-12-01

    Cancrum oris (noma) is a gangrenous infection that develops in the mouth and spreads rapidly to other parts of the face. The disease occurs mostly in conditions of poverty, poor hygiene and malnutrition. In sub-Saharan Africa the frequency in several countries is estimated to be 1-7 cases per 1,000 population, and as many as 12 cases per 1,000 in the most affected communities. About 90% of these children die without receiving any care, yet the disease can, and should, be prevented. With increasing numbers of children who are malnourished and who have compromised immune systems (compounded by the HIV pandemic) the prevalence of conditions such as noma is likely to increase. Among the earliest features of noma are excessive salivation, marked fetor oris, facial oedema and a greyish-black discolouration of the skin in the affected area. This devastating gangrenous lesion may involve the cheek, the chin, the infra-orbital margin, palate, nose, antrum and virtually any part of the face. This report describes a 4-year-old HIV-positive African girl, who was abandoned, discharged from the Plastics Unit and now lives in a child care sanctuary. Little is known about her history prior to her arrival at the home a few weeks previously. The clinical examination revealed a delay in growth and physical development equivalent to that of a 2-year-old child. The left cheek had a perforating ulcer in a healing phase. The perforation, about 1 cm in diameter, was surrounded by oedematous tissues showing a mild to moderate erythema. The peripheral oedema extended to the lower palpebral, the upper labial, left labial commissural, mandibular and pre-parotid regions. Submental, submandibular and cervical lymph nodes were mildly painful upon palpation. The child was not pyretic. The intra-oral examination revealed the features of acute necrotising gingivitis (ANG). ANG was generalised and showed classic interdental crater-like ulcers covered with whitish debris. Halitosis was pronounced

  17. 3D-Ultrasonography for evaluation of facial muscles in patients with chronic facial palsy or defective healing: a pilot study

    PubMed Central

    2014-01-01

    Background While standardized methods are established to examine the pathway from motorcortex to the peripheral nerve in patients with facial palsy, a reliable method to evaluate the facial muscles in patients with long-term palsy for therapy planning is lacking. Methods A 3D ultrasonographic (US) acquisition system driven by a motorized linear mover combined with conventional US probe was used to acquire 3D data sets of several facial muscles on both sides of the face in a healthy subject and seven patients with different types of unilateral degenerative facial nerve lesions. Results The US results were correlated to the duration of palsy and the electromyography results. Consistent 3D US based volumetry through bilateral comparison was feasible for parts of the frontalis muscle, orbicularis oculi muscle, depressor anguli oris muscle, depressor labii inferioris muscle, and mentalis muscle. With the exception of the frontal muscle, the facial muscles volumes were much smaller on the palsy side (minimum: 3% for the depressor labii inferior muscle) than on the healthy side in patients with severe facial nerve lesion. In contrast, the frontal muscles did not show a side difference. In the two patients with defective healing after spontaneous regeneration a decrease in muscle volume was not seen. Synkinesis and hyperkinesis was even more correlated to muscle hypertrophy on the palsy compared with the healthy side. Conclusion 3D ultrasonography seems to be a promising tool for regional and quantitative evaluation of facial muscles in patients with facial palsy receiving a facial reconstructive surgery or conservative treatment. PMID:24782657

  18. Human Muscle Fiber

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The stimulus of gravity affects RNA production, which helps maintain the strength of human muscles on Earth (top), as seen in this section of muscle fiber taken from an astronaut before spaceflight. Astronauts in orbit and patients on Earth fighting muscle-wasting diseases need countermeasures to prevent muscle atrophy, indicated here with white lipid droplets (bottom) in the muscle sample taken from the same astronaut after spaceflight. Kerneth Baldwin of the University of California, Irvine, is conducting research on how reducing the stimulus of gravity affects production of the RNA that the body uses as a blueprint for making muscle proteins. Muscle proteins are what give muscles their strength, so when the RNA blueprints aren't available for producing new proteins to replace old ones -- a situation that occurs in microgravity -- the muscles atrophy. When the skeletal muscle system is exposed to microgravity during spaceflight, the muscles undergo a reduced mass that translates to a reduction in strength. When this happens, muscle endurance decreases and the muscles are more prone to injury, so individuals could have problems in performing extravehicular activity [space walks] or emergency egress because their bodies are functionally compromised.

  19. Muscle strain injuries.

    PubMed

    Garrett, W E

    1996-01-01

    One of the most common injuries seen in the office of the practicing physician is the muscle strain. Until recently, little data were available on the basic science and clinical application of this basic science for the treatment and prevention of muscle strains. Studies in the last 10 years represent action taken on the direction of investigation into muscle strain injuries from the laboratory and clinical fronts. Findings from the laboratory indicate that certain muscles are susceptible to strain injury (muscles that cross multiple joints or have complex architecture). These muscles have a strain threshold for both passive and active injury. Strain injury is not the result of muscle contraction alone, rather, strains are the result of excessive stretch or stretch while the muscle is being activated. When the muscle tears, the damage is localized very near the muscle-tendon junction. After injury, the muscle is weaker and at risk for further injury. The force output of the muscle returns over the following days as the muscle undertakes a predictable progression toward tissue healing. Current imaging studies have been used clinically to document the site of injury to the muscle-tendon junction. The commonly injured muscles have been described and include the hamstring, the rectus femoris, gastrocnemius, and adductor longus muscles. Injuries inconsistent with involvement of a single muscle-tendon junction proved to be at tendinous origins rather than within the muscle belly. Important information has also been provided regarding injuries with poor prognosis, which are potentially repairable surgically, including injuries to the rectus femoris muscle, the hamstring origin, and the abdominal wall. Data important to the management of common muscle injuries have been published. The risks of reinjury have been documented. The early efficacy and potential for long-term risks of nonsteroidal antiinflammatory agents have been shown. New data can also be applied to the field

  20. EMG study for perioral facial muscles function during mastication.

    PubMed

    Hanawa, S; Tsuboi, A; Watanabe, M; Sasaki, K

    2008-03-01

    This study aimed to clarify the temporal and quantitative modulation in the orbicularis oris (OO) and buccinator (BUC) muscle activities during mastication. Ten healthy males (26.9 +/- 1.0 years) participated. Electromyograms (EMGs) of the facial muscles were recorded with fine wire electrodes when chewing the chewing gum (one to four sticks) and peanuts (one to five pieces). Surface EMGs of the masseter (MAS) and digastric muscles were recorded simultaneously. EMGs of the OO and BUC showed rhythmic single-peaked bursts corresponding to the jaw-opening phase of chewing cycles. The total cycle lengths were constant regardless of the food amount. Integrated EMGs of the OO changed significantly when the amount of both foods changed (anova: P < 0.05). Those of the BUC changed significantly with the amount of gum changed (P < 0.05), but did not change with the amount of peanuts changed. The burst duration of OO changed significantly when the amount of gum changed during ipsilateral chewing (P < 0.05). When the amount of peanuts changed during ipsilateral chewing, the onset of OO and the peak of BUC based on the onset of MAS activity changed significantly (P < 0.05). However, the onset, peak and offset of the OO and BUC based on the offset of MAS did not change regardless of the amounts chewed. The changes of the OO and BUC activities may derive from chewing-generated sensory inputs in accordance with the physical property of food in part, which would relate to the function of these muscles during mastication.

  1. Fluorescence Processes in the Outer Atmospheres of the Evolved M-Stars Alpha Ori (M2 Iab) and Gamma Cru (M3.4 III)

    NASA Astrophysics Data System (ADS)

    Carpenter, Kenneth; Kober, Gladys; Nielsen, Krister; Ayres, Thomas; Wahlgren, Glenn

    2015-08-01

    The prototypical M-giant and M-supergiant stars, Gamma Cru (M3.4 III)) and Alpha Ori (M2Iab), have been observed as part of the "Advanced Spectral Library (ASTRAL) Project: Cool Stars" (PI = T. Ayres). "ASTRAL-Cool Stars" is an HST Cycle 18 Treasury Program designed to collect, using the Space Telescope Imaging Spectrograph (STIS), a definitive set of representative, high-resolution (R~46,000 in the FUV up to ~1700 Å, R~30,000 for 1700-2150 Å, and R~114,000 >2150 Å) and high signal/noise (S/N>100) UV spectra of eight F-M evolved cool stars. These extremely high-quality UV echelle spectra are available from the HST archive and through the University of Colorado (http://casa.colorado.edu/~ayres/ASTRAL/). In this paper, we use the very rich emission-line spectra of the two evolved M stars in the sample, Gamma Cru (GaCrux) and Alpha Ori (Betelgeuse), to study the fluorescence processes operating in their outer atmospheres. We summarize the pumping transitions and fluorescent line products known on the basis of previous work and newly identified in our on-going analysis of these extraordinary new “Treasury” spectra. Detailed descriptions of selected processes are given to illustrate their operation. The wide variety of fluorescence processes in operation in these outer atmospheres, both molecular and atomic, suggest that there is a mixture of warm and cool plasmas present and that H I Ly-alpha in particular is locally very strong, even though, in the case of Alpha Ori, no flux is seen at earth due to strong circumstellar absorption at that wavelength. Many new fluorescence line products and several new processes have been identified in these spectra, which are more complete and of higher S/N than previously available for these stars.

  2. Requirement of the N-terminal residues of human cytomegalovirus UL112-113 proteins for viral growth and oriLyt-dependent DNA replication.

    PubMed

    Kim, Young-Eui; Park, Mi Young; Kang, Kyeong Jin; Han, Tae Hee; Lee, Chan Hee; Ahn, Jin-Hyun

    2015-08-01

    The UL112-113 region of the human cytomegalovirus (HCMV) genome encodes four phosphoproteins of 34, 43, 50, and 84 kDa that promote viral DNA replication. Co-transfection assays have demonstrated that self-interaction of these proteins via the shared N-termini is necessary for their intranuclear distribution as foci and for the efficient relocation of a viral DNA polymerase processivity factor (UL44) to the viral replication sites. However, the requirement of UL112-113 N-terminal residues for viral growth and DNA replication has not been fully elucidated. Here, we investigated the effect of deletion of the N-terminal regions of UL112-113 proteins on viral growth and oriLyt-dependent DNA replication. A deletion of the entire UL112 region or the region encoding the 25 N-terminal amino-acid residues from the HCMV (Towne strain) bacmid impaired viral growth in bacmid-transfected human fibroblast cells, indicating their requirement for viral growth. In co-immunoprecipitation assays using the genomic gene expressing the four UL112-113 proteins together, the 25 N-terminal amino-acid residues were found to be necessary for stable expression of UL112-113 proteins and their self-interaction. These residues were also required for efficient binding to and relocation of UL44, but not for interaction with IE2, an origin-binding transcription factor. In co-transfection/replication assays, replication of the oriLyt-containing plasmid was promoted by expression of intact UL112-113 proteins, but not by the expression of 25-amino-acid residue-deleted proteins. Our results demonstrate that the 25 N-terminal amino-acid residues of UL112-113 proteins that mediate self-interaction contribute to viral growth by promoting their binding to UL44 and the initiation of oriLyt-dependent DNA replication.

  3. Healthy Muscles Matter

    MedlinePlus

    ... keep my muscles more healthy? Definitions What can go wrong? Injuries Almost everyone has had sore muscles ... If you have been inactive, “start low and go slow” by gradually increasing how often and how ...

  4. Respiratory muscle plasticity.

    PubMed

    Rowley, Katharine L; Mantilla, Carlos B; Sieck, Gary C

    2005-07-28

    Plasticity of respiratory muscles must be considered in the context of their unique physiological demands. The continuous rhythmic activation of respiratory muscles makes them among the most active in the body. Respiratory muscles, especially the diaphragm, are non-weight-bearing, and thus, in contrast to limb muscles, are not exposed to gravitational effects. Perturbations in normal activation and load known to induce plasticity in limb muscles may not cause similar adaptations in respiratory muscles. In this review, we explore the structural and functional properties of the diaphragm muscle and their response to alterations in load and activity. Overall, relatively modest changes in diaphragm structural and functional properties occur in response to perturbations in load or activity. However, disruptions in the normal influence of phrenic innervation by frank denervation, tetrodotoxin nerve block and spinal hemisection, induce profound changes in the diaphragm, indicating the substantial trophic influence of phrenic motoneurons on diaphragm muscle.

  5. Eye muscle repair - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100062.htm Eye muscle repair - series—Normal anatomy To use the sharing ... the eyeball to the eye socket. The external muscles of the eye are found behind the conjunctiva. ...

  6. An Sp1/Sp3 site in the downstream region of varicella-zoster virus (VZV) oriS influences origin-dependent DNA replication and flanking gene transcription and is important for VZV replication in vitro and in human skin.

    PubMed

    Khalil, Mohamed I; Robinson, Makeda; Sommer, Marvin; Arvin, Ann; Hay, John; Ruyechan, William T

    2012-12-01

    The distribution and orientation of origin-binding protein (OBP) sites are the main architectural contrasts between varicella-zoster virus (VZV) and herpes simplex virus (HSV) origins of DNA replication (oriS). One important difference is the absence of a downstream OBP site in VZV, raising the possibility that an alternative cis element may replace its function. Our previous work established that Sp1, Sp3, and YY1 bind to specific sites within the downstream region of VZV oriS; we hypothesize that one or both of these sites may be the alternative cis element(s). Here, we show that the mutation of the Sp1/Sp3 site decreases DNA replication and transcription from the adjacent ORF62 and ORF63 promoters following superinfection with VZV. In contrast, in the absence of DNA replication or in transfection experiments with ORF62, only ORF63 transcription is affected. YY1 site mutations had no significant effect on either process. Recombinant viruses containing these mutations were then constructed. The Sp1/Sp3 site mutant exhibited a significant decrease in virus growth in MeWo cells and in human skin xenografts, while the YY1 site mutant virus grew as well as the wild type in MeWo cells, even showing a late increase in VZV replication in skin xenografts following infection. These results suggest that the Sp1/Sp3 site plays an important role in both VZV origin-dependent DNA replication and ORF62 and ORF63 transcription and that, in contrast to HSV, these events are linked during virus replication.

  7. Muscle Session Summary

    NASA Technical Reports Server (NTRS)

    Baldwin, Kenneth; Feeback, Daniel

    1999-01-01

    Presentations from the assembled group of investigators involved in specific research projeects related to skeletal muscle in space flight can categorized in thematic subtopics: regulation of contractile protein phenotypes, muscle growth and atrophy, muscle structure: injury, recovery,and regeneration, metabolism and fatigue, and motor control and loading factors.

  8. Oxidative Metabolism in Muscle

    NASA Astrophysics Data System (ADS)

    Ferrari, M.; Binzoni, T.; Quaresima, V.

    1997-06-01

    Oxidative metabolism is the dominant source of energy for skeletal muscle. Near-infrared spectroscopy allows the non-invasive measurement of local oxygenation, blood flow and oxygen consumption. Although several muscle studies have been made using various near-infrared optical techniques, it is still difficult to interpret the local muscle metabolism properly. The main findings of near-infrared spectroscopy muscle studies in human physiology and clinical medicine are summarized. The advantages and problems of near-infrared spectroscopy measurements, in resting and exercising skeletal muscles studies, are discussed through some representative examples.

  9. Homology of the jaw muscles in lizards and snakes-a solution from a comparative gnathostome approach.

    PubMed

    Johnston, Peter

    2014-03-01

    Homology or shared evolutionary origin of jaw adductor muscles in lizards and snakes has been difficult to establish, although snakes clearly arose within the lizard radiation. Lizards typically have temporal adductors layered lateral to medial, and in snakes the muscles are arranged in a rostral to caudal pattern. Recent work has suggested that the jaw adductor group in gnathostomes is arranged as a folded sheet; when this theory is applied to snakes, homology with lizard morphology can be seen. This conclusion revisits the work of S.B. McDowell, J Herpetol 1986; 20:353-407, who proposed that homology involves identity of m. levator anguli oris and the loss of m. adductor mandibulae externus profundus, at least in "advanced" (colubroid) snakes. Here I advance the folded sheet hypothesis across the whole snake tree using new and literature data, and provide a solution to this homology problem.

  10. Frenulectomy of the tongue and the influence of rehabilitation exercises on the sEMG activity of masticatory muscles.

    PubMed

    Tecco, Simona; Baldini, Aberto; Mummolo, Stefano; Marchetti, Enrico; Giuca, Maria Rita; Marzo, Giuseppe; Gherlone, Enrico Felice

    2015-08-01

    This study aimed to assess by surface electromyography (sEMG) the changes in sub-mental, orbicularis oris, and masticatory muscle activity after a lingual frenulectomy. Rehabilitation exercises in subjects with ankyloglossia, characterized by Class I malocclusion, were assessed as well. A total of 24 subjects were selected. Thirteen subjects (mean age 7±2.5years) with Class I malocclusion and ankyloglossia were treated with lingual frenulectomy and rehabilitation exercises, while 11 subjects (mean age 7±0.8years) with normal occlusion and normal lingual frenulum were used as controls. The inclusion criteria for both groups were the presence of mixed dentition and no previous orthodontic treatment. The sEMG recordings were taken at the time of the first visit (T0), and after 1 (T1) and 6months (T2) for the treated group. Recordings were taken at the same time for the control group. Due to the noise inherent with the sEMG recording, special attention was paid to obtain reproducible and standardized recordings. The tested muscles were the masseter, anterior temporalis, upper and lower orbicularis oris, and sub-mental muscles. The sEMG recordings were performed at rest, while kissing, swallowing, opening the mouth, clenching the teeth and during protrusion of the mandible. These recordings were made by placing electrodes in the area of muscle contraction. At T0, the treated group showed different sEMG activity of the muscles with respect to the control group, with significant differences at rest and during some test tasks (p<0.05). In the treated group, an increase in sEMG potentials was observed for the masseter muscle, from T0 to T2, during maximal voluntary clenching. During swallowing and kissing, the masseter and sub-mental muscles showed a significant increase in their sEMG potentials from T0 to T2. During the protrusion of the mandible, the masseter and anterior temporalis significantly decreased their sEMG activity, while the sub-mental area increased

  11. A muscle stem cell for every muscle: variability of satellite cell biology among different muscle groups.

    PubMed

    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.

  12. 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

  13. Une nouvelle théorie de la cinétique des réactions radical-radical

    NASA Astrophysics Data System (ADS)

    Green, N. J. B.; Rickerby, A. G.

    1999-01-01

    Radical recombination reactions are of central importance in radiation chemistry. In general such reactions are slower than diffusion-controlled because of the radical spins. The rate constant is corrected by a multiplicative spin statistical factor, which represents the probability that the radicals encounter one another in a reactive state. However, this method does not account for the possibility that the reactivity of a pair may recover following an unreactive encounter, for example by spin relaxation or by a coherent evolution of the spin function. In this paper we show how the spin statistical factor can be corrected for the recovery of reactivity. The new theory covers a large range of mechanisms for the recovery of reactivity, and gives simple analytical results. Both steady-state and transient solutions are presented and the former are tested against experiment for the reaction between the hydrated electron and oxygen, and for the magnetic field effect on the rate constant of an elementary reaction. Les réactions de recombinaison entre deux radicaux libres ont une grande importance en chimie sous rayonnement. En général, du fait du spin des radicaux, de telles réactions sont moins rapides que celles qui sont contrôlées par la diffusion. Les constantes de vitesse sont corrigées par un facteur multiplicatif, le facteur statistique de spin, qui représente la probabilité pour que les radicaux se rencontrent, l'un avec l'autre, dans un état réactif. Cependant, cette méthode ne tient pas compte de la possibilité pour que la même paire se rencontre plusieurs fois en raison de rencontres non-réactives. Ensuite la réactivité de cette paire peut se rétablir par exemple par relaxation de spins, ou par évolution cohérente d'une superposition des états de spin. Dans cet article on démontre comment on peut corriger le facteur statistique de spin pour le rétablissement de la réactivité. La nouvelle théorie couvre un large domaine de m

  14. Muscle injuries: optimising recovery.

    PubMed

    Järvinen, Tero A H; Järvinen, Teppo L N; Kääriäinen, Minna; Aärimaa, Ville; Vaittinen, Samuli; Kalimo, Hannu; Järvinen, Markku

    2007-04-01

    Muscle injuries are one of the most common traumas occurring in sports. Despite their clinical importance, there are only a few clinical studies on the treatment of muscle injuries. Lack of clinical studies is most probably attributable to the fact that there is not only a high heterogeneity in the severity of injuries, but also the injuries take place in different muscles, making it very demanding to carry out clinical trials. Accordingly, the current treatment principles of muscle injuries have either been derived from experimental studies or been tested empirically only. Clinically, first aid for muscle injuries follows the RICE (Rest, Ice, Compression and Elevation) principle. The objective of RICE is to stop the injury-induced bleeding into the muscle tissue and thereby minimise the extent of the injury. Clinical examination should be carried out immediately after the injury and 5-7 days after the initial trauma, at which point the severity of the injury can be assessed more reliably. At that time, a more detailed characterisation of the injury can be made using imaging diagnostic modalities (ultrasound or MRI) if desired. The treatment of injured skeletal muscle should be carried out by immediate immobilisation of the injured muscle (clinically, relative immobility/avoidance of muscle contractions). However, the duration of immobilisation should be limited to a period sufficient to produce a scar of sufficient strength to bear the forces induced by remobilisation without re-rupture and the return to activity (mobilisation) should then be started gradually within the limits of pain. Early return to activity is needed to optimise the regeneration of healing muscle and recovery of the flexibility and strength of the injured skeletal muscle to pre-injury levels. The rehabilitation programme should be built around progressive agility and trunk stabilisation exercises, as these exercises seem to yield better outcome for injured skeletal muscle than programmes based

  15. Muscle development and obesity

    PubMed Central

    2008-01-01

    The formation of skeletal muscle from the epithelial somites involves a series of events triggered by temporally and spatially discrete signals resulting in the generation of muscle fibers which vary in their contractile and metabolic nature. The fiber type composition of muscles varies between individuals and it has now been found that there are differences in fiber type proportions between lean and obese animals and humans. Amongst the possible causes of obesity, it has been suggested that inappropriate prenatal environments may ‘program’ the fetus and may lead to increased risks for disease in adult life. The characteristics of muscle are both heritable and plastic, giving the tissue some ability to adapt to signals and stimuli both pre and postnatally. Given that muscle is a site of fatty acid oxidation and carbohydrate metabolism and that its development can be changed by prenatal events, it is interesting to examine the possible relationship between muscle development and the risk of obesity. PMID:19279728

  16. Muscle Changes in Aging

    PubMed Central

    Siparsky, Patrick N.; Kirkendall, Donald T.; Garrett, William E.

    2014-01-01

    Muscle physiology in the aging athlete is complex. Sarcopenia, the age-related decrease in lean muscle mass, can alter activity level and affect quality of life. This review addresses the microscopic and macroscopic changes in muscle with age, recognizes contributing factors including nutrition and changes in hormone levels, and identifies potential pharmacologic agents in clinical trial that may aid in the battle of this complex, costly, and disabling problem. Level of Evidence: Level 5. PMID:24427440

  17. MUSCLE INJURIES IN ATHLETES

    PubMed Central

    Barroso, Guilherme Campos; Thiele, Edilson Schwansee

    2015-01-01

    This article had the aim of demonstrating the physiology, diagnosis and treatment of muscle injuries, focusing on athletes and their demands and expectations. Muscle injuries are among the most common complaints in orthopedic practice, occurring both among athletes and among non-athletes. These injuries present a challenge for specialists, due to the slow recovery, during which time athletes are unable to take part in training and competitions, and due to frequent sequelae and recurrences of the injuries. Most muscle injuries (between 10% and 55% of all injuries) occur during sports activities. The muscles most commonly affected are the ischiotibial, quadriceps and gastrocnemius. These muscles go across two joints and are more subject to acceleration and deceleration forces. The treatment for muscle injuries varies from conservative treatment to surgery. New procedures are being used, like the hyperbaric chamber and the use of growth factors. However, there is still a high rate of injury recurrence. Muscle injury continues to be a topic of much controversy. New treatments are being researched and developed, but prevention through muscle strengthening, stretching exercises and muscle balance continues to be the best “treatment”. PMID:27027021

  18. MUSCLE INJURIES IN ATHLETES.

    PubMed

    Barroso, Guilherme Campos; Thiele, Edilson Schwansee

    2011-01-01

    This article had the aim of demonstrating the physiology, diagnosis and treatment of muscle injuries, focusing on athletes and their demands and expectations. Muscle injuries are among the most common complaints in orthopedic practice, occurring both among athletes and among non-athletes. These injuries present a challenge for specialists, due to the slow recovery, during which time athletes are unable to take part in training and competitions, and due to frequent sequelae and recurrences of the injuries. Most muscle injuries (between 10% and 55% of all injuries) occur during sports activities. The muscles most commonly affected are the ischiotibial, quadriceps and gastrocnemius. These muscles go across two joints and are more subject to acceleration and deceleration forces. The treatment for muscle injuries varies from conservative treatment to surgery. New procedures are being used, like the hyperbaric chamber and the use of growth factors. However, there is still a high rate of injury recurrence. Muscle injury continues to be a topic of much controversy. New treatments are being researched and developed, but prevention through muscle strengthening, stretching exercises and muscle balance continues to be the best "treatment".

  19. Ischemia causes muscle fatigue

    NASA Technical Reports Server (NTRS)

    Murthy, G.; Hargens, A. R.; Lehman, S.; Rempel, D. M.

    2001-01-01

    The purpose of this investigation was to determine whether ischemia, which reduces oxygenation in the extensor carpi radialis (ECR) muscle, causes a reduction in muscle force production. In eight subjects, muscle oxygenation (TO2) of the right ECR was measured noninvasively and continuously using near infrared spectroscopy (NIRS) while muscle twitch force was elicited by transcutaneous electrical stimulation (1 Hz, 0.1 ms). Baseline measurements of blood volume, muscle oxygenation and twitch force were recorded continuously, then a tourniquet on the upper arm was inflated to one of five different pressure levels: 20, 40, 60 mm Hg (randomized order) and diastolic (69 +/- 9.8 mm Hg) and systolic (106 +/- 12.8 mm Hg) blood pressures. Each pressure level was maintained for 3-5 min, and was followed by a recovery period sufficient to allow measurements to return to baseline. For each respective tourniquet pressure level, mean TO2 decreased from resting baseline (100% TO2) to 99 +/- 1.2% (SEM), 96 +/- 1.9%, 93 +/- 2.8%, 90 +/- 2.5%, and 86 +/- 2.7%, and mean twitch force decreased from resting baseline (100% force) to 99 +/- 0.7% (SEM), 96 +/- 2.7%, 93 +/- 3.1%, 88 +/- 3.2%, and 86 +/- 2.6%. Muscle oxygenation and twitch force at 60 mm Hg tourniquet compression and above were significantly lower (P < 0.05) than baseline value. Reduced twitch force was correlated in a dose-dependent manner with reduced muscle oxygenation (r = 0.78, P < 0.001). Although the correlation does not prove causation, the results indicate that ischemia leading to a 7% or greater reduction in muscle oxygenation causes decreased muscle force production in the forearm extensor muscle. Thus, ischemia associated with a modest decline in TO2 causes muscle fatigue.

  20. A Type I Signal Peptidase Is Required for Pilus Assembly in the Gram-Positive, Biofilm-Forming Bacterium Actinomyces oris

    PubMed Central

    Siegel, Sara D.

    2016-01-01

    ABSTRACT The Gram-positive bacterium Actinomyces oris, a key colonizer in the development of oral biofilms, contains 18 LPXTG motif-containing proteins, including fimbrillins that constitute two fimbrial types critical for adherence, biofilm formation, and polymicrobial interactions. Export of these protein precursors, which harbor a signal peptide, is thought to be mediated by the Sec machine and require cleavage of the signal peptide by type I signal peptidases (SPases). Like many Gram-positive bacteria, A. oris expresses two SPases, named LepB1 and LepB2. The latter has been linked to suppression of lethal “glyco-stress,” caused by membrane accumulation of the LPXTG motif-containing glycoprotein GspA when the housekeeping sortase srtA is genetically disrupted. Consistent with this finding, we show here that a mutant lacking lepB2 and srtA was unable to produce high levels of glycosylated GspA and hence was viable. However, deletion of neither lepB1 nor lepB2 abrogated the signal peptide cleavage and glycosylation of GspA, indicating redundancy of SPases for GspA. In contrast, the lepB2 deletion mutant failed to assemble the wild-type levels of type 1 and 2 fimbriae, which are built by the shaft fimbrillins FimP and FimA, respectively; this phenotype was attributed to aberrant cleavage of the fimbrillin signal peptides. Furthermore, the lepB2 mutants, including the catalytically inactive S101A and K169A variants, exhibited significant defects in polymicrobial interactions and biofilm formation. Conversely, lepB1 was dispensable for the aforementioned processes. These results support the idea that LepB2 is specifically utilized for processing of fimbrial proteins, thus providing an experimental model with which to study the basis of type I SPase specificity. IMPORTANCE Sec-mediated translocation of bacterial protein precursors across the cytoplasmic membrane involves cleavage of their signal peptide by a signal peptidase (SPase). Like many Gram

  1. Research opportunities in muscle atrophy

    NASA Technical Reports Server (NTRS)

    Herbison, G. J.; Talbot, J. M.

    1984-01-01

    A trophy of skeletal muscle; muscle a trophy associated with manned space flight; the nature, causes, and mechanisms of muscle atrophy associated with space flight, selected physiological factors, biochemical aspects, and countermeasures are addressed.

  2. Suzaku Observation of Strong Fluorescent Iron Line Emission from the Young Stellar Object V1647 Ori during Its New X-ray Outburst

    NASA Technical Reports Server (NTRS)

    Hamaguchi, Kenji; Grosso, Nicolas; Kastner, Joel H.; Weintraub, David A.; Richmond, Michael

    2009-01-01

    The Suzaku X-ray satellite observed the young stellar object V1647 Ori on 2008 October 8 during the new mass accretion outburst reported in August 2008. During the 87 ksec observation with a net exposure of 40 ks, V1647 Ori showed a. high level of X-ray emission with a gradual decrease in flux by a factor of 5 and then displayed an abrupt flux increase by an order of magnitude. Such enhanced X-ray variability was also seen in XMM-Newton observations in 2004 and 2005 during the 2003-2005 outburst, but has rarely been observed for other young stellar objects. The spectrum clearly displays emission from Helium-like iron, which is a signature of hot plasma (kT approx.5 keV). It also shows a fluorescent iron Ka line with a remarkably large equivalent width of approx. 600 eV. Such a, large equivalent width indicates that a part of the incident X-ray emission that irradiates the circumstellar material and/or the stellar surface is hidden from our line of sight. XMM-Newton spectra during the 2003-2005 outburst did not show a strong fluorescent iron Ka line ; so that the structure of the circumstellar gas very close to the stellar core that absorbs and re-emits X-ray emission from the central object may have changed in between 2005 and 2008. This phenomenon may be related to changes in the infrared morphology of McNeil's nebula between 2004 and 2008.

  3. Respiratory muscle plasticity.

    PubMed

    Gransee, Heather M; Mantilla, Carlos B; Sieck, Gary C

    2012-04-01

    Muscle plasticity is defined as the ability of a given muscle to alter its structural and functional properties in accordance with the environmental conditions imposed on it. As such, respiratory muscle is in a constant state of remodeling, and the basis of muscle's plasticity is its ability to change protein expression and resultant protein balance in response to varying environmental conditions. Here, we will describe the changes of respiratory muscle imposed by extrinsic changes in mechanical load, activity, and innervation. Although there is a large body of literature on the structural and functional plasticity of respiratory muscles, we are only beginning to understand the molecular-scale protein changes that contribute to protein balance. We will give an overview of key mechanisms regulating protein synthesis and protein degradation, as well as the complex interactions between them. We suggest future application of a systems biology approach that would develop a mathematical model of protein balance and greatly improve treatments in a variety of clinical settings related to maintaining both muscle mass and optimal contractile function of respiratory muscles.

  4. Onion artificial muscles

    NASA Astrophysics Data System (ADS)

    Chen, Chien-Chun; Shih, Wen-Pin; Chang, Pei-Zen; Lai, Hsi-Mei; Chang, Shing-Yun; Huang, Pin-Chun; Jeng, Huai-An

    2015-05-01

    Artificial muscles are soft actuators with the capability of either bending or contraction/elongation subjected to external stimulation. However, there are currently no artificial muscles that can accomplish these actions simultaneously. We found that the single layered, latticed microstructure of onion epidermal cells after acid treatment became elastic and could simultaneously stretch and bend when an electric field was applied. By modulating the magnitude of the voltage, the artificial muscle made of onion epidermal cells would deflect in opposing directions while either contracting or elongating. At voltages of 0-50 V, the artificial muscle elongated and had a maximum deflection of -30 μm; at voltages of 50-1000 V, the artificial muscle contracted and deflected 1.0 mm. The maximum force response is 20 μN at 1000 V.

  5. Variable gearing in pennate muscles.

    PubMed

    Azizi, Emanuel; Brainerd, Elizabeth L; Roberts, Thomas J

    2008-02-05

    Muscle fiber architecture, i.e., the physical arrangement of fibers within a muscle, is an important determinant of a muscle's mechanical function. In pennate muscles, fibers are oriented at an angle to the muscle's line of action and rotate as they shorten, becoming more oblique such that the fraction of force directed along the muscle's line of action decreases throughout a contraction. Fiber rotation decreases a muscle's output force but increases output velocity by allowing the muscle to function at a higher gear ratio (muscle velocity/fiber velocity). The magnitude of fiber rotation, and therefore gear ratio, depends on how the muscle changes shape in the dimensions orthogonal to the muscle's line of action. Here, we show that gear ratio is not fixed for a given muscle but decreases significantly with the force of contraction (P < 0.0001). We find that dynamic muscle-shape changes promote fiber rotation at low forces and resist fiber rotation at high forces. As a result, gearing varies automatically with the load, to favor velocity output during low-load contractions and force output for contractions against high loads. Therefore, muscle-shape changes act as an automatic transmission system allowing a pennate muscle to shift from a high gear during rapid contractions to low gear during forceful contractions. These results suggest that variable gearing in pennate muscles provides a mechanism to modulate muscle performance during mechanically diverse functions.

  6. Painful unilateral temporalis muscle enlargement: reactive masticatory muscle hypertrophy.

    PubMed

    Katsetos, Christos D; Bianchi, Michael A; Jaffery, Fizza; Koutzaki, Sirma; Zarella, Mark; Slater, Robert

    2014-06-01

    An instance of isolated unilateral temporalis muscle hypertrophy (reactive masticatory muscle hypertrophy with fiber type 1 predominance) confirmed by muscle biopsy with histochemical fiber typing and image analysis in a 62 year-old man is reported. The patient presented with bruxism and a painful swelling of the temple. Absence of asymmetry or other abnormalities of the craniofacial skeleton was confirmed by magnetic resonance imaging and cephalometric analyses. The patient achieved symptomatic improvement only after undergoing botulinum toxin injections. Muscle biopsy is key in the diagnosis of reactive masticatory muscle hypertrophy and its distinction from masticatory muscle myopathy (hypertrophic branchial myopathy) and other non-reactive causes of painful asymmetric temporalis muscle enlargement.

  7. Skeletal muscle-smooth muscle interaction: an unusual myoelastic system.

    PubMed

    Hikida, R S; Peterson, W J

    1983-09-01

    The serratus superficialis metapatagialis (SSM) of pigeons is a skeletal muscle with unusual properties. It lies between the ribs and the trailing edge of the wing, where it is attached to the skin by a system of smooth muscles having elastic tendons. Wing movements during flight induce marked changes in this muscle's length. The SSM inserts onto the deep fascia, and at its termination the skeletal muscle contains large numbers of microtubules. Many myofibrils attach to leptomeric organelles, which then attach to the terminal end of the skeletal muscle fiber. The deep fascia next connects to the dermis of the skin by bundles of smooth muscles that have elastic tendons at both ends. This system allows large movements of the muscle while preventing its fibers from overstretching. The movements and presumed forces acting at this muscle make the presence of sensory receptors such as muscle spindles unlikely. Spindles are absent in this muscle.

  8. Muscle Fiber Types and Training.

    ERIC Educational Resources Information Center

    Karp, Jason R.

    2001-01-01

    The specific types of fibers that make up individual muscles greatly influence how people will adapt to their training programs. This paper explains the complexities of skeletal muscles, focusing on types of muscle fibers (slow-twitch and fast-twitch), recruitment of muscle fibers to perform a motor task, and determining fiber type. Implications…

  9. Research opportunities in muscle atrophy

    NASA Technical Reports Server (NTRS)

    Herbison, G. J. (Editor); Talbot, J. M. (Editor)

    1984-01-01

    Muscle atrophy in a weightless environment is studied. Topics of investigation include physiological factors of muscle atrophy in space flight, biochemistry, countermeasures, modelling of atrophied muscle tissue, and various methods of measurement of muscle strength and endurance. A review of the current literature and suggestions for future research are included.

  10. Muscle function loss

    MedlinePlus

    ... Paralytic shellfish poisoning Periodic paralysis Focal nerve injury Polio Spinal cord injury Stroke Home Care Sudden loss ... Barré syndrome Muscle cramps Poisoning - fish and shellfish Polio Stroke Review Date 2/27/2016 Updated by: ...

  11. Muscle biopsy (image)

    MedlinePlus

    A muscle biopsy involves removal of a plug of tissue usually by a needle to be later used for examination. Sometimes ... there is a patchy condition expected an open biopsy may be used. Open biopsy involves a small ...

  12. Neurogenic muscle cramps.

    PubMed

    Katzberg, Hans D

    2015-08-01

    Muscle cramps are sustained, painful contractions of muscle and are prevalent in patients with and without medical conditions. The objective of this review is to present updates on the mechanism, investigation and treatment of neurogenic muscle cramps. PubMed and Embase databases were queried between January 1980 and July 2014 for English-language human studies. The American Academy of Neurology classification of studies (classes I-IV) was used to assess levels of evidence. Mechanical disruption, ephaptic transmission, disruption of sensory afferents and persistent inward currents have been implicated in the pathogenesis of neurogenic cramps. Investigations are directed toward identifying physiological triggers or medical conditions predisposing to cramps. Although cramps can be self-limiting, disabling or sustained muscle cramps should prompt investigation for underlying medical conditions. Lifestyle modifications, treatment of underlying conditions, stretching, B-complex vitamins, diltiezam, mexiletine, carbamazepine, tetrahydrocannabinoid, leveteracitam and quinine sulfate have shown evidence for treatment.

  13. Metabolic Diseases of Muscle

    MedlinePlus

    ... levels of fats, which are the major muscle energy fuels for those with the disorder. A partial deficiency ... genetic defect ( ) interferes with the processing of specific fuels, energy shortages can occur and toxic byproducts may build ...

  14. Buccinator muscle repositioning

    PubMed Central

    Baghele, Om N.

    2012-01-01

    Anatomical aberrations and abnormalities are frequently associated with functional, psychosocial, and emotional problems. One such aberration is crestal attachment of frenum or muscle on the alveolar processes of the jaws. Crestal attachment of buccinator muscle is a rare phenomenon, which may pose various problems in routine oral exercises/functions or restoring the edentulous area. A case of abnormal buccinator muscle attachment is presented here, which was relocated apically by surgical means using an acrylic stent. The healing was uneventful and significant apical repositioning was observed. A fixed bridge was fabricated and the long-term results of the restorative therapy were assured because the patient could maintain the oral hygiene well after the muscle repositioning operation. PMID:23162347

  15. 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

  16. An invertebrate smooth muscle with striated muscle myosin filaments.

    PubMed

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

    2015-10-20

    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.

  17. Muscle as a secretory organ.

    PubMed

    Pedersen, Bente K

    2013-07-01

    Skeletal muscle is the largest organ in the body. Skeletal muscles are primarily characterized by their mechanical activity required for posture, movement, and breathing, which depends on muscle fiber contractions. However, skeletal muscle is not just a component in our locomotor system. Recent evidence has identified skeletal muscle as a secretory organ. We have suggested that cytokines and other peptides that are produced, expressed, and released by muscle fibers and exert either autocrine, paracrine, or endocrine effects should be classified as "myokines." The muscle secretome consists of several hundred secreted peptides. This finding provides a conceptual basis and a whole new paradigm for understanding how muscles communicate with other organs such as adipose tissue, liver, pancreas, bones, and brain. In addition, several myokines exert their effects within the muscle itself. Many proteins produced by skeletal muscle are dependent upon contraction. Therefore, it is likely that myokines may contribute in the mediation of the health benefits of exercise.

  18. Changes in T2-weighted MRI of supinator muscle, pronator teres muscle, and extensor indicis muscle with manual muscle testing

    PubMed Central

    Yoshida, Kazuya; Akiyama, Sumikazu; Takamori, Masayoshi; Otsuka, D. Eng, Hiroshi; Seo, Yoshiteru

    2017-01-01

    [Purpose] In order to detect muscle activity with manual muscle testing, T2-weighted magnetic resonance (T2w-MR) images were detected by a 0.2 T compact MRI system. [Subjects and Methods] The subjects were 3 adult males. Transverse T2-weighted multi-slice spin-echo images of the left forearm were measured by a 39 ms echo-time with a 2,000 ms repetition time, a 9.5 mm slice thickness, 1 accumulation and a total image acquisition time of 4 min 16 s. First, T2w-MR images in the resting condition were measured. Then, manipulative isometric contraction exercise (5 sec duration) to the supinator muscle, the pronator teres muscle or the extensor indicis muscle was performed using Borg’s rating of perceived exertion (RPE) scale of 15–17. The T2w-MR images were measured immediately after the exercise. [Results] T2w-MR image intensities increased significantly in the supinator muscle, the pronator teres muscle and the extensor indicis muscle after the exercise. However, the image intensities in the rest of the muscle did not change. [Conclusion] Using T2w-MR images, we could detect muscle activity in a deep muscle, the supinator muscle, and a small muscle, the extensor indicis muscle. These results also support the reliability of the manual muscle testing method. PMID:28356621

  19. Muscle hardness characteristics of the masseter muscle after repetitive muscle activation: comparison to the biceps brachii muscle.

    PubMed

    Kashima, Koji; Higashinaka, Shuichi; Watanabe, Naoshi; Maeda, Sho; Shiba, Ryosuke

    2004-10-01

    The purpose of this study was to compare hardness characteristics of the masseter muscle to those of the biceps brachii muscle during repetitive muscle movements. Seventeen asymptomatic female subjects participated in this study. Each subject, on separate days, undertook a 5-minute unilateral chewing gum task on the right side and a 5-minute flexion-extension exercise on the right hand with a 2kg dumbbell. Using a handheld hardness meter, muscle hardness was measured in the right masseter and in the biceps brachii muscle at eight time points (before the task, immediately after the task, and at 1, 3, 5, 10, 30, and 60 minutes after the task), and the data obtained before and after the task on each muscle were compared. Comparisons of the normalized data were also performed between the two muscles at each time point. As a result, a significant increase in muscle hardness was seen at 1 minute after the task in the biceps brachii muscle (p=0.0093). In contrast, the masseter muscle showed a tendency to lower hardness, with the lowest point of hardness occurring at 10 minutes after the task (p = 0.0160). Between the two muscles, there was a difference in the normalized data immediately after the task, and at 1, 5, and 10 minutes after the task (0.01 muscle hardness characteristics of the masseter muscle completely differed from those of the biceps brachii muscle after repetitive muscle activation.

  20. Muscle wasting in cancer.

    PubMed

    Johns, N; Stephens, N A; Fearon, K C H

    2013-10-01

    Skeletal muscle loss appears to be the most significant clinical event in cancer cachexia and is associated with a poor outcome. With regard to such muscle loss, despite extensive study in a range of models, there is ongoing debate as to whether a reduction in protein synthesis, an increase in degradation or a combination of both is the more relevant. Each model differs in terms of key mediators and the pathways activated in skeletal muscle. Certain models do suggest that decreased synthesis accompanied by enhanced protein degradation via the ubiquitin proteasome pathway (UPP) is important. Murine models tend to involve rapid development of cachexia and may represent more acute muscle atrophy rather than the chronic wasting observed in humans. There is a paucity of human data both at a basic descriptive level and at a molecular/mechanism level. Progress in treating the human form of cancer cachexia can only move forwards through carefully designed large randomised controlled clinical trials of specific therapies with validated biomarkers of relevance to underlying mechanisms. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting.

  1. Positronium Formation in Muscle

    PubMed Central

    Gustafson, D. R.

    1970-01-01

    Positronium formation in muscle at +4°C and -4°C was examined by the measurement of the angular correlation of positron annihilation radiation. Since the positronium formation rate in ice is considerably higher than it is in water, there should be a comparable increase in the positronium formation rate in muscle tissue if recent speculation that cellular water is ordered in a semicrystalline icelike state is correct. Comparison of the angular correlation from muscle at +4°C with that from water at +4°C shows no enhancement of the positronium formation rate. Frozen muscle at -4°C shows an enhancement of the positronium formation rate of approximately half that found in ice at -4°C, indicating that most cellular water undergoes a normal water-ice transition when frozen. It is concluded therefore that cell water in muscle is not ordered in a hexagonal icelike structure. While the results are consistent with the hypothesis that cell water is in the liquid state, the hypothesis that cell water is ordered in an undetermined close packed structure which transforms to the hexagonal ice structure at or near 0°C cannot be ruled out. PMID:5436881

  2. Emended description of Actinomyces naeslundii and descriptions of Actinomyces oris sp. nov. and Actinomyces johnsonii sp. nov., previously identified as Actinomyces naeslundii genospecies 1, 2 and WVA 963.

    PubMed

    Henssge, Uta; Do, Thuy; Radford, David R; Gilbert, Steven C; Clark, Douglas; Beighton, David

    2009-03-01

    Actinomyces naeslundii is an important early colonizer in the oral biofilm and consists of three genospecies (1, 2 and WVA 963) which cannot be readily differentiated using conventional phenotypic testing or on the basis of 16S rRNA gene sequencing. We have investigated a representative collection of type and reference strains and clinical and oral isolates (n=115) and determined the partial gene sequences of six housekeeping genes (atpA, rpoB, pgi, metG, gltA and gyrA). These sequences identified the three genospecies and differentiated them from Actinomyces viscosus isolated from rodents. The partial sequences of atpA and metG gave best separation of the three genospecies. A. naeslundii genospecies 1 and 2 formed two distinct clusters, well separated from both genospecies WVA 963 and A. viscosus. Analysis of the same genes in other oral Actinomyces species (Actinomyces gerencseriae, A. israelii, A. meyeri, A. odontolyticus and A. georgiae) indicated that, when sequence data were obtained, these species each exhibited <90 % similarity with the A. naeslundii genospecies. Based on these data, we propose the name Actinomyces oris sp. nov. (type strain ATCC 27044(T) =CCUG 34288(T)) for A. naeslundii genospecies 2 and Actinomyces johnsonii sp. nov. (type strain ATCC 49338(T) =CCUG 34287(T)) for A. naeslundii genospecies WVA 963. A. naeslundii genospecies 1 should remain as A. naeslundii sensu stricto, with the type strain ATCC 12104(T) =NCTC 10301(T) =CCUG 2238(T).

  3. An innovative team-based stop smoking competition among Māori and Pacific Island smokers: rationale and method for the study and its evaluation

    PubMed Central

    2013-01-01

    Background Māori and Pacific Island people have significantly higher smoking rates compared to the rest of the New Zealand population. The main aim of this paper is to describe how knowledge of Indigenous people’s practices and principles can be combined with proven effective smoking cessation support into a cessation intervention appropriate for Indigenous people. Methods/Design A literature review was conducted to identify what cultural principles and practices could be used to increase salience, and what competition elements could have an impact on efficacy of smoking cessation. The identified elements were incorporated into the design of a cessation intervention. Discussion Cultural practices incorporated into the intervention include having a holistic family or group-centred focus, inter-group competitiveness, fundraising and ritual pledging. Competition elements included are social support, pharmacotherapy use, cash prize incentives and the use of a dedicated website and iPad application. A pre-test post-test will be combined with process evaluation to evaluate if the competition results in triggering mass-quitting, utilisation of pharmacotherapy and in increasing sustained smoking cessation and to get a comprehensive understanding of the way in which they contribute to the effect. The present study is the first to describe how knowledge about cultural practices and principles can be combined with proven cessation support into a smoking cessation contest. The findings from this study are promising and further more rigorous testing is warranted. PMID:24365329

  4. The AT-rich tract of the SV40 ori core: negative synergism and specific recognition by single stranded and duplex DNA binding proteins.

    PubMed Central

    Galli, I; Iguchi-Ariga, S M; Ariga, H

    1992-01-01

    The SV40 origin of replication comprises a run of thymine and adenine residues. Integrity of this AT-rich sequence is known to be essential for replication. We set out to study whether or not these elements can work synergistically to sustain replication. Quite surprisingly, additional copies of the AT stretch linked to a functional SV40 ori core dramatically reduce its replication in Cosl cells, probably by creating some physical block. Interestingly, the same inhibiting effect can be observed with the addition in cis of the yeast ARS consensus, which is homologous to the SV40 AT stretch. This modulation is possibly due to the action of cellular factors that recognize either of the two sequences. In fact, we demonstrate the existence of factor(s) in Cosl crude nuclear extracts that in vitro can specifically bind to either of them. Moreover, we show that these sequence-specific factor(s) (MW about 50 kDa), named SOAP, recognize both single (T-rich strand) and double stranded forms of the AT tracts. Binding to single stranded AT stretches can be specifically inhibited by the corresponding duplex form, but not vice versa. Images PMID:1321411

  5. Cisplatin selects short forms of the mitochondrial DNA OriB variant (16184–16193 poly-cytosine tract), which confer resistance to cisplatin

    PubMed Central

    Amo, Taku; Kamimura, Naomi; Asano, Hiromasa; Asoh, Sadamitsu; Ohta, Shigeo

    2017-01-01

    A number of alternations in mitochondrial DNA (mtDNA) have been reported in different types of cancers, and the role of mtDNA in cancer has been attracting increasing interest. In order to investigate the relationship between mtDNA alternations and chemosensitivity, we constructed cybrid (trans-mitochondrial hybrid) cell lines carrying a HeLa nucleus and the mtDNA of healthy individuals because of the presence of somatic alternations in the mtDNA of many cancer cells. After a treatment with 1.0 μg/mL cisplatin for 10 days, we isolated 100 cisplatin-resistant clones, 70 of which carried the shorter mtDNA OriB variant (16184–16193 poly-cytosine tract), which was located in the control region of mtDNA. Whole mtDNA sequencing of 10 clones revealed no additional alternations. Re-construction of the HeLa nucleus and mtDNA from cisplatin-resistant cells showed that cisplatin resistance was only acquired by mtDNA alternations in the control region, and not by possible alternation(s) in the nuclear genome. PMID:28393913

  6. The role of the IRE1 pathway in excessive iodide- and/or fluoride-induced apoptosis in Nthy-ori 3-1 cells in vitro.

    PubMed

    Liu, Hongliang; Zeng, Qiang; Cui, Yushan; Zhao, Liang; Zhang, Lei; Fu, Gang; Hou, Changchun; Zhang, Shun; Yu, Linyu; Jiang, Chunyang; Wang, Zhenglun; Chen, Xuemin; Wang, Aiguo

    2014-01-30

    Excessive iodide and fluoride coexist in the groundwater in many regions, causing a potential risk to the human thyroid. To investigate the mechanism of iodide- and fluoride-induced thyroid cytotoxicity, human thyroid follicular epithelial cells (Nthy-ori 3-1) were treated with different concentrations of potassium iodide (KI), with or without sodium fluoride (NaF). Cell morphology, viability, lactate dehydrogenase (LDH) leakage, apoptosis, and expression of inositol-requiring enzyme 1 (IRE1) pathway-related molecules were assessed. Results showed 50 mM of KI, 1 mM of NaF, and 50 mM of KI +1 mM of NaF changed cellular morphology, decreased viability, and increased LDH leakage and apoptosis. Elevated expression of binding protein (BiP), IRE1, and C/EBP homologous protein (CHOP) mRNA and protein, as well as spliced X-box-binding protein-1 (sXBP-1) mRNA, were observed in the 1 mM NaF and 50 mM KI +1 mM NaF groups. Collectively, excessive iodide and/or fluoride is cytotoxic to the human thyroid. Although these data do not manifest iodide could induce the IRE1 pathway, the cytotoxicity followed by exposure to fluoride alone or in combination with iodide may be related to IRE1 pathway-induced apoptosis. Furthermore, exposure to the combination of excessive iodide and fluoride may cause interactive effects on thyroid cytotoxicity.

  7. Keeping Kids Smokefree: rationale, design, and implementation of a community, school, and family-based intervention to modify behaviors related to smoking among Māori and Pacific Island children in New Zealand.

    PubMed

    Glover, Marewa; Scragg, Robert; Nosa, Vili; Bullen, Chris; McCool, Judith; Kira, Anette

    Despite a concerted, sustained and comprehensive tobacco control effort, smoking is prevalent among young people in New Zealand, particularly for Māori and Pacific Island teenagers. Many took up smoking in their pre-teen years. New Zealand research has shown that daily smoking by children aged 14-15 years is strongly influenced by parental smoking. The Keeping Kids Smokefree study is investigating whether changing parental smoking behavior and attitudes via a community-partnership approach with parents, schools, and local health providers can reduce smoking initiation by 11-12 year olds. It is a quasi-experimental trial involving four schools in an urban area of high social deprivation with large numbers of Māori and Pacific Islands families. Schools were allocated to intervention or control and the intervention was developed through a process of engagement with the schools, parents of children and local healthcare organizations. This article describes the rationale, context, methodology and methods involved in establishing the study. Building Māori and Pacific Islander research capacity was a secondary objective of the study.

  8. Effects of interceptive orthodontics on orbicular muscle activity: a surface electromyographic study in children.

    PubMed

    Saccucci, M; Tecco, S; Ierardoa, G; Luzzi, V; Festa, F; Polimeni, A

    2011-08-01

    The purpose of this study was to assess by surface electromyography (sEMG) the changes in upper and lower orbicular oris (OO) muscles produced by a preformed functional device in subjects with Class II, division 1 malocclusion, deep bite, and labial incompetence. Twenty-eight subjects were selected: 13 subjects (mean age 9 ± 1.5 years) with Class II malocclusion, deep bite, and labial incompetence were treated with a preformed functional device, while 15 subjects (mean age 9.5 ± 0.8 years) with normal occlusion were used as control. Inclusion criteria for both groups were: presence of mixed dentition, no previous orthodontic treatment, and absence of speech disturbance. sEMG recordings were taken at the time of the first visit (T0), and after 3 (T1) and 6 months (T2) for the treated group, and at T0 and T2 for the control group. The sEMG recording was performed at rest, and while kissing, swallowing, opening the mouth, clenching the teeth, and during protrusion of the mandible, by placing electrodes at the area of muscle contraction. At T0, except during swallowing, the treated group always showed a lower sEMG activity of the lower OO muscle with respect to the control group, with significant differences at rest and during mandibular protrusion (p<0.05). In the treated group, a significant increase in muscle tone was observed for the lower OO muscle from T0 to T1, but only at rest. The upper OO muscle showed a significant increase during the protrusion of the mandible from T1 to T2. No significant change was observed in the control group during the follow-up. Muscular contractility of treated patients at T2 reached the same values as that of the control group at T2. Interceptive orthodontics seems to improve the form and function of the orofacial muscle structure. Improvement in muscle contraction after treatment was demonstrated by sEMG.

  9. Hysteresis in Muscle

    NASA Astrophysics Data System (ADS)

    Ramos, Jorgelina; Lynch, Stephen; Jones, David; Degens, Hans

    This paper presents examples of hysteresis from a broad range of scientific disciplines and demonstrates a variety of forms including clockwise, counterclockwise, butterfly, pinched and kiss-and-go, respectively. These examples include mechanical systems made up of springs and dampers which have been the main components of muscle models for nearly one hundred years. For the first time, as far as the authors are aware, hysteresis is demonstrated in single fibre muscle when subjected to both lengthening and shortening periodic contractions. The hysteresis observed in the experiments is of two forms. Without any relaxation at the end of lengthening or shortening, the hysteresis loop is a convex clockwise loop, whereas a concave clockwise hysteresis loop (labeled as kiss-and-go) is formed when the muscle is relaxed at the end of lengthening and shortening. This paper also presents a mathematical model which reproduces the hysteresis curves in the same form as the experimental data.

  10. Artificial muscles on heat

    NASA Astrophysics Data System (ADS)

    McKay, Thomas G.; Shin, Dong Ki; Percy, Steven; Knight, Chris; McGarry, Scott; Anderson, Iain A.

    2014-03-01

    Many devices and processes produce low grade waste heat. Some of these include combustion engines, electrical circuits, biological processes and industrial processes. To harvest this heat energy thermoelectric devices, using the Seebeck effect, are commonly used. However, these devices have limitations in efficiency, and usable voltage. This paper investigates the viability of a Stirling engine coupled to an artificial muscle energy harvester to efficiently convert heat energy into electrical energy. The results present the testing of the prototype generator which produced 200 μW when operating at 75°C. Pathways for improved performance are discussed which include optimising the electronic control of the artificial muscle, adjusting the mechanical properties of the artificial muscle to work optimally with the remainder of the system, good sealing, and tuning the resonance of the displacer to minimise the power required to drive it.

  11. Hydraulically actuated artificial muscles

    NASA Astrophysics Data System (ADS)

    Meller, M. A.; Tiwari, R.; Wajcs, K. B.; Moses, C.; Reveles, I.; Garcia, E.

    2012-04-01

    Hydraulic Artificial Muscles (HAMs) consisting of a polymer tube constrained by a nylon mesh are presented in this paper. Despite the actuation mechanism being similar to its popular counterpart, which are pneumatically actuated (PAM), HAMs have not been studied in depth. HAMs offer the advantage of compliance, large force to weight ratio, low maintenance, and low cost over traditional hydraulic cylinders. Muscle characterization for isometric and isobaric tests are discussed and compared to PAMs. A model incorporating the effect of mesh angle and friction have also been developed. In addition, differential swelling of the muscle on actuation has also been included in the model. An application of lab fabricated HAMs for a meso-scale robotic system is also presented.

  12. Imaging of skeletal muscle.

    PubMed

    Goodwin, Douglas W

    2011-05-01

    Various diagnostic imaging techniques such as sonography, computed tomography, scintigraphy, radiography, and magnetic resonance imaging (MRI) have made possible the noninvasive evaluation of skeletal muscle injury and disease. Although these different modalities have roles to play, MRI is especially sensitive in the diagnosis of muscle disorders and injury and has proved to be useful in determining the extent of disease, in directing interventions, and in monitoring the response to therapies. This article describes how magnetic resonance images are formed and how the signal intensities in T1- and T2-weighted images may be used for diagnosis of the above-mentioned conditions and injuries.

  13. Physical Rehabilitation Improves Muscle Function Following Volumetric Muscle Loss Injury

    DTIC Science & Technology

    2014-12-19

    diabetes ) conditions [17,18]. For acute muscle injuries, it has been shown to accelerate muscle healing/ regeneration by modulating the immune response...The foot of the animal was strapped to a footplate attached to a dual-mode muscle lever system (Aurora Scientific Inc., ON, Canada), and the knee and...Combination of exercise training and diet restriction normalizes limited exercise capacity and impaired skeletal muscle function in diet-induced diabetic mice

  14. Composition of Muscle Fiber Types in Rat Rotator Cuff Muscles.

    PubMed

    Rui, Yongjun; Pan, Feng; Mi, Jingyi

    2016-10-01

    The rat is a suitable model to study human rotator cuff pathology owing to the similarities in morphological anatomy structure. However, few studies have reported the composition muscle fiber types of rotator cuff muscles in the rat. In this study, the myosin heavy chain (MyHC) isoforms were stained by immunofluorescence to show the muscle fiber types composition and distribution in rotator cuff muscles of the rat. It was found that rotator cuff muscles in the rat were of mixed fiber type composition. The majority of rotator cuff fibers labeled positively for MyHCII. Moreover, the rat rotator cuff muscles contained hybrid fibers. So, compared with human rotator cuff muscles composed partly of slow-twitch fibers, the majority of fast-twitch fibers in rat rotator cuff muscles should be considered when the rat model study focus on the pathological process of rotator cuff muscles after injury. Gaining greater insight into muscle fiber types in rotator cuff muscles of the rat may contribute to elucidate the mechanism of pathological change in rotator cuff muscles-related diseases. Anat Rec, 299:1397-1401, 2016. © 2016 Wiley Periodicals, Inc.

  15. Anti-smooth muscle antibody

    MedlinePlus

    ... gov/ency/article/003531.htm Anti-smooth muscle antibody To use the sharing features on this page, please enable JavaScript. Anti-smooth muscle antibody is a blood test that detects the presence ...

  16. Gantzer muscle. An anatomical study

    PubMed Central

    Caetano, Edie Benedito; Sabongi, João José; Vieira, Luiz Ângelo; Caetano, Maurício Ferreira; Moraes, Daniel Vinhais

    2015-01-01

    OBJECTIVE: The relationship of Gantzer muscle to the median and anterior interosseous nerve is debated. METHODS: Ìn an anatomical study with 80 limbs from 40 cadavers the incidence, origin, insertion, nerve supply and relations of Gantzer muscle have been documented. RESULTS: The muscle was found in 54 forearms (68% of limbs) and was supplied by the anterior interosseous nerve. It arose from the deep surface of the flexor digitorum superficialis muscle, (42 limbs), coronoid process (eight limbs) and medial epicondyle (seven limbs). Its insertion was to the ulnar part of flexor pollicis longus muscle. The Gantzer muscle always lay posterior to both the median and anterior interosseous nerve. CONCLUSION: The Gantzer muscle may contribute to the median nerve and anterior interosseous nerve compression. The muscle was found in 68% of limbs and should be considered a normal anatomical pattern rather than an anatomical variation. Level of Evidence IV, Case Series . PMID:27069404

  17. Active vs. inactive muscle (image)

    MedlinePlus

    ... may lose 20 to 40 percent of their muscle -- and, along with it, their strength -- as they ... have found that a major reason people lose muscle is because they stop doing everyday activities that ...

  18. Genetics Home Reference: rippling muscle disease

    MedlinePlus

    ... C. Mutations in CAV3 cause mechanical hyperirritability of skeletal muscle in rippling muscle disease. Nat Genet. 2001 Jul; ... silent" action potentials in the tubular system of skeletal muscle fibers. Muscle Nerve. 2005 May;31(5):652- ...

  19. Volumetric muscle loss

    DTIC Science & Technology

    2011-01-01

    muscles. Videos facilitate gait analysis and the evaluation of other functional movements.6 These im- ages can be added to the electronic medical record to...FL, August 16-19, 2010. 6. Brunnekreef JJ, van Uden CJ, van Moorsel S, Kooloos JG: Reliability of videotaped observational gait analysis in patients

  20. Sculpturing new muscle phenotypes

    NASA Technical Reports Server (NTRS)

    Babij, P.; Booth, F. W.

    1988-01-01

    Changes in the pattern of muscle activity are followed by new patterns of protein synthesis, both in the contractile elements and in the enzymes of energy metabolism. Although the signal transducers have not been identified, techniques of molecular biology have clearly shown that the adaptive responses are the regulated consequence of differential gene expression.

  1. Hindlimb suspension reduces muscle regeneration

    NASA Technical Reports Server (NTRS)

    Mozdziak, P. E.; Truong, Q.; Macius, A.; Schultz, E.

    1998-01-01

    Exposure of juvenile skeletal muscle to a weightless environment reduces growth and satellite cell mitotic activity. However, the effect of a weightless environment on the satellite cell population during muscle repair remains unknown. Muscle injury was induced in rat soleus muscles using the myotoxic snake venom, notexin. Rats were placed into hindlimb-suspended or weightbearing groups for 10 days following injury. Cellular proliferation during regeneration was evaluated using 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry and image analysis. Hindlimb suspension reduced (P < 0.05) regenerated muscle mass, regenerated myofiber diameter, uninjured muscle mass, and uninjured myofiber diameter compared to weightbearing rats. Hindlimb suspension reduced (P < 0.05) BrdU labeling in uninjured soleus muscles compared to weight-bearing muscles. However, hindlimb suspension did not abolish muscle regeneration because myofibers formed in the injured soleus muscles of hindlimb-suspended rats, and BrdU labeling was equivalent (P > 0.10) on myofiber segments isolated from the soleus muscles of hindlimb-suspended and weightbearing rats following injury. Thus, hindlimb suspension (weightlessness) does not suppress satellite cell mitotic activity in regenerating muscles before myofiber formation, but reduces growth of the newly formed myofibers.

  2. Nerve-muscle interactions during flight muscle development in Drosophila

    NASA Technical Reports Server (NTRS)

    Fernandes, J. J.; Keshishian, H.

    1998-01-01

    During Drosophila pupal metamorphosis, the motoneurons and muscles differentiate synchronously, providing an opportunity for extensive intercellular regulation during synapse formation. We examined the existence of such interactions by developmentally delaying or permanently eliminating synaptic partners during the formation of indirect flight muscles. When we experimentally delayed muscle development, we found that although adult-specific primary motoneuron branching still occurred, the higher order (synaptic) branching was suspended until the delayed muscle fibers reached a favourable developmental state. In reciprocal experiments we found that denervation caused a decrease in the myoblast pool. Furthermore, the formation of certain muscle fibers (dorsoventral muscles) was specifically blocked. Exceptions were the adult muscles that use larval muscle fibers as myoblast fusion targets (dorsal longitudinal muscles). However, when these muscles were experimentally compelled to develop without their larval precursors, they showed an absolute dependence on the motoneurons for their formation. These data show that the size of the myoblast pool and early events in fiber formation depend on the presence of the nerve, and that, conversely, peripheral arbor development and synaptogenesis is closely synchronized with the developmental state of the muscle.

  3. The muscle spindle as a feedback element in muscle control

    NASA Technical Reports Server (NTRS)

    Andrews, L. T.; Iannone, A. M.; Ewing, D. J.

    1973-01-01

    The muscle spindle, the feedback element in the myotatic (stretch) reflex, is a major contributor to muscular control. Therefore, an accurate description of behavior of the muscle spindle during active contraction of the muscle, as well as during passive stretch, is essential to the understanding of muscle control. Animal experiments were performed in order to obtain the data necessary to model the muscle spindle. Spectral density functions were used to identify a linear approximation of the two types of nerve endings from the spindle. A model reference adaptive control system was used on a hybrid computer to optimize the anatomically defined lumped parameter estimate of the spindle. The derived nonlinear model accurately predicts the behavior of the muscle spindle both during active discharge and during its silent period. This model is used to determine the mechanism employed to control muscle movement.

  4. The Rep78 gene product of adeno-associated virus (AAV) self-associates to form a hexameric complex in the presence of AAV ori sequences.

    PubMed Central

    Smith, R H; Spano, A J; Kotin, R M

    1997-01-01

    The Rep78 and Rep68 proteins of adeno-associated virus (AAV) are replication initiator proteins that bind the viral replicative-form origin of replication, nick the origin in a site- and strand-specific fashion, and mediate vectorial unwinding of the DNA duplex via an ATP-dependent helicase activity, thus initiating a strand displacement mechanism of viral DNA replication. Genetic and biochemical studies have identified Rep mutants that demonstrate a trans-dominant negative phenotype in vitro and in vivo, suggesting the possibility that multimerization of Rep is essential for certain replicative functions. In this study, we have investigated the ability of the largest of the Rep proteins, Rep78, to self-associate in vitro and in vivo. Self-association of Rep78 in vivo was demonstrated through the use of a mammalian two-hybrid system. Rep-Rep protein interaction was confirmed in vitro through coimmunoprecipitation experiments with a bacterially expressed maltose-binding protein-Rep78 fusion protein in combination with [35S]methionine-labeled Rep78 synthesized in a coupled in vitro transcription-translation system. Mapping studies with N- and C-terminal truncation mutant forms of Rep indicate that amino acid sequences required for maximal self-association occur between residues 164 and 484. Site-directed mutagenesis identified two essential motifs within this 321-amino-acid region: (i) a putative alpha-helix bearing a 3,4-hydrophobic heptad repeat reminiscent of those found in coiled-coil domains and (ii) a previously recognized nucleoside triphosphate-binding motif. Deletion of either of these regions from the full-length polypeptide resulted in severe impairment of Rep-Rep interaction. In addition, gel filtration chromatography and protein cross-linking experiments indicated that Rep78 forms a hexameric complex in the presence of AAV ori sequences. PMID:9151837

  5. Partitioning of the Linear Chromosome during Sporulation of Streptomyces coelicolor A3(2) Involves an oriC-Linked parAB Locus

    PubMed Central

    Kim, Hyun-Jin; Calcutt, Michael J.; Schmidt, Francis J.; Chater, Keith F.

    2000-01-01

    Candidate partitioning genes (parA and parB) for the linear chromosome of Streptomyces coelicolor were identified by DNA sequencing in a series of seven genes located between rnpA and trxA near the chromosomal replication origin. The most likely translation start point of parB overlapped the parA stop codon, suggestive of coregulation, and transcription analysis suggested that the two genes formed an operon. Deletion of part of parB had no effect on the growth or appearance of colonies but caused a deficiency in DNA partitioning during the multiple septation events involved in converting aerial hyphae into long chains of spores. At least 13% of spore compartments failed to inherit the normal DNA allocation. The same phenotype was obtained with a deletion removing a segment of DNA from both parA and parB. Reinforcing the idea of a special role for the par locus during sporulation, the stronger of two parAB promoters was greatly upregulated at about the time when sporulation septation was maximal in colonies. Three copies of a 14-bp inverted repeat (GTTTCACGTGAAAC) were found in or near the parAB genes, and at least 12 more identical copies were identified within 100 kb of oriC from the growing genome sequence database. Only one perfect copy of the 14-bp sequence was present in approximately 5 Mb of sequence available from the rest of the genome. The 14-bp sequence was similar to sequences identified as binding sites for Spo0J, a ParB homologue from Bacillus subtilis believed to be important for DNA partitioning (D. C.-H. Lin and A. D. Grossman, Cell 92:675–685, 1998). One of these sites encompassed the transcription start point of the stronger parA promoter. PMID:10671452

  6. Eye-rima oris distance and its relation to the vertical dimension of occlusion measured by two methods: Anthropometric study in a sample of Yemeni dental students

    PubMed Central

    Alhajj, Mohammed Nasser; Khalifa, Nadia; Amran, Abdullah

    2016-01-01

    Objective: This study was conducted to evaluate the relationship between the distance measured from the distal outer of the eye to the parting line of the lips and the occlusal vertical dimension (OVD) measured by two methods. Methods: One hundred and fourteen dental students (76 males and 38 females) were recruited for this study with mean age (22.34 ± 1.83) years. The distance from distal canthus of the eye to rima oris (eye-RO) was compared with two different measurements of the OVD (nasal [N] to gnathion [Gn], and subnasal [Sn] to menton [Me]). All distances were measured using modified digital caliper. Results: Pearson correlation coefficient test for correlations and paired samples t-test for differences were used with a significant level of (P < 0.05). There was a positive significant correlation between the eye-RO distance and the two measurements of the OVD. However, this correlation was stronger between eye-RO and the distance from the tip of the nose to the tip of the chin than that between eye-RO and the distance from the septum of the nose to the under of the chin (r = 0.313 with P = 0.0007, r = 0.296 with P = 0.0014), respectively. Conclusion: The distance from the outer canthus of the eye to the parting of the lips seems to be a reliable method in predicting the OVD and should relate to the distance from the tip of the nose to the tip of the chin. PMID:27011736

  7. Congenital dystrophic medial rectus muscles

    PubMed Central

    Murthy, Ramesh

    2017-01-01

    We report two patients, one with congenital dystrophic medial rectus muscles and one with absence of the medial rectus muscles; in addition, one of them had absence of the lateral rectus muscles. While absence of the superior oblique and superior rectus has been more commonly reported in literature, especially with craniofacial syndromes, our patients were nonsyndromic. Considering the risk of anterior segment ischemia, correction of the large-angle exotropia was performed by horizontal rectus muscle surgery where possible, along with transfer of the superior oblique tendon to the superior part of the normal medial rectus muscle insertion area to create a tethering effect with a good outcome. PMID:28300745

  8. Iliopsoas muscle injury in dogs.

    PubMed

    Cabon, Quentin; Bolliger, Christian

    2013-05-01

    The iliopsoas muscle is formed by the psoas major and iliacus muscles. Due to its length and diameter, the iliopsoas muscle is an important flexor and stabilizer of the hip joint and the vertebral column. Traumatic acute and chronic myopathies of the iliopsoas muscle are commonly diagnosed by digital palpation during the orthopedic examination. Clinical presentations range from gait abnormalities, lameness, and decreased hip joint extension to irreversible fibrotic contracture of the muscle. Rehabilitation of canine patients has to take into account the inciting cause, the severity of pathology and the presence of muscular imbalances.

  9. INTERMEDIATE FILAMENTS IN SMOOTH MUSCLE

    PubMed Central

    Tang, Dale D.

    2008-01-01

    The intermediate filament (IF) network is one of the three cytoskeletal systems in smooth muscle. The type III IF proteins vimentin and desmin are major constituents of the network in smooth muscle cells and tissues. Lack of vimentin or desmin impairs contractile ability of various smooth muscle preparations, implying their important role for smooth muscle force development. The IF framework has long been viewed as a fixed cytostructure that solely provides mechanical integrity for the cell. However, recent studies suggest that the IF cytoskeleton is dynamic in mammalian cells in response to various external stimulation. In this review, the structure and biological properties of IF proteins in smooth muscle are summarized. The role of IF proteins in the modulation of smooth muscle force development and redistribution/translocation of signaling partners (such as p130 Crk-associated substrate, CAS) is depicted. This review also summarizes our latest understanding on how the IF network may be regulated in smooth muscle. PMID:18256275

  10. Skeletal muscle adaptations and muscle genomics of performance horses.

    PubMed

    Rivero, José-Luis L; Hill, Emmeline W

    2016-03-01

    Skeletal muscles in horses are characterised by specific adaptations, which are the result of the natural evolution of the horse as a grazing animal, centuries of selective breeding and the adaptability of this tissue in response to training. These adaptations include an increased muscle mass relative to body weight, a great locomotor efficiency based upon an admirable muscle-tendon architectural design and an adaptable fibre-type composition with intrinsic shortening velocities greater than would be predicted from an animal of comparable body size. Furthermore, equine skeletal muscles have a high mitochondrial volume that permits a higher whole animal aerobic capacity, as well as large intramuscular stores of energy substrates (glycogen in particular). Finally, high buffer and lactate transport capacities preserve muscles against fatigue during anaerobic exercise. Many of these adaptations can improve with training. The publication of the equine genome sequence in 2009 has provided a major advance towards an improved understanding of equine muscle physiology. Equine muscle genomics studies have revealed a number of genes associated with elite physical performance and have also identified changes in structural and metabolic genes following exercise and training. Genes involved in muscle growth, muscle contraction and specific metabolic pathways have been found to be functionally relevant for the early performance evaluation of elite athletic horses. The candidate genes discussed in this review are important for a healthy individual to improve performance. However, muscle performance limiting conditions are widespread in horses and many of these conditions are also genetically influenced.

  11. Mechanotransduction in skeletal muscle

    PubMed Central

    Burkholder, Thomas J.

    2007-01-01

    Mechanical signals are critical to the development and maintenance of skeletal muscle, but the mechanisms that convert these shape changes to biochemical signals is not known. When a deformation is imposed on a muscle, changes in cellular and molecular conformations link the mechanical forces with biochemical signals, and the close integration of mechanical signals with electrical, metabolic, and hormonal signaling may disguise the aspect of the response that is specific to the mechanical forces. The mechanically induced conformational change may directly activate downstream signaling and may trigger messenger systems to activate signaling indirectly. Major effectors of mechanotransduction include the ubiquitous mitogen activated protein kinase (MAP) and phosphatidylinositol-3’ kinase (PI-3K), which have well described receptor dependent cascades, but the chain of events leading from mechanical stimulation to biochemical cascade is not clear. This review will discuss the mechanics of biological deformation, loading of cellular and molecular structures, and some of the principal signaling mechanisms associated with mechanotransduction. PMID:17127292

  12. Mentalis muscle related reflexes.

    PubMed

    Gündüz, Ayşegül; Uyanık, Özlem; Ertürk, Özdem; Sohtaoğlu, Melis; Kızıltan, Meral Erdemir

    2016-05-01

    The mentalis muscle (MM) arises from the incisive fossa of the mandible, raises and protrudes the lower lip. Here, we aim to characterize responses obtained from MM by supraorbital and median electrical as well as auditory stimuli in a group of 16 healthy volunteers who did not have clinical palmomental reflex. Reflex activities were recorded from the MM and orbicularis oculi (O.oc) after supraorbital and median electrical as well as auditory stimuli. Response rates over MM were consistent after each stimulus, however, mean latencies of MM response were longer than O.oc responses by all stimulation modalities. Shapes and amplitudes of responses from O.oc and MM were similar. Based on our findings, we may say that MM motoneurons have connections with trigeminal, vestibulocochlear and lemniscal pathways similar to other facial muscles and electrophysiological recording of MM responses after electrical and auditory stimulation is possible in healthy subjects.

  13. Muscle Motion Solenoid Actuator

    NASA Astrophysics Data System (ADS)

    Obata, Shuji

    It is one of our dreams to mechanically recover the lost body for damaged humans. Realistic humanoid robots composed of such machines require muscle motion actuators controlled by all pulling actions. Particularly, antagonistic pairs of bi-articular muscles are very important in animal's motions. A system of actuators is proposed using the electromagnetic force of the solenoids with the abilities of the stroke length over 10 cm and the strength about 20 N, which are needed to move the real human arm. The devised actuators are based on developments of recent modern electro-magnetic materials, where old time materials can not give such possibility. Composite actuators are controlled by a high ability computer and software making genuine motions.

  14. Linear artificial molecular muscles.

    PubMed

    Liu, Yi; Flood, Amar H; Bonvallet, Paul A; Vignon, Scott A; Northrop, Brian H; Tseng, Hsian-Rong; Jeppesen, Jan O; Huang, Tony J; Brough, Branden; Baller, Marko; Magonov, Sergei; Solares, Santiago D; Goddard, William A; Ho, Chih-Ming; Stoddart, J Fraser

    2005-07-13

    Two switchable, palindromically constituted bistable [3]rotaxanes have been designed and synthesized with a pair of mechanically mobile rings encircling a single dumbbell. These designs are reminiscent of a "molecular muscle" for the purposes of amplifying and harnessing molecular mechanical motions. The location of the two cyclobis(paraquat-p-phenylene) (CBPQT(4+)) rings can be controlled to be on either tetrathiafulvalene (TTF) or naphthalene (NP) stations, either chemically ((1)H NMR spectroscopy) or electrochemically (cyclic voltammetry), such that switching of inter-ring distances from 4.2 to 1.4 nm mimics the contraction and extension of skeletal muscle, albeit on a shorter length scale. Fast scan-rate cyclic voltammetry at low temperatures reveals stepwise oxidations and movements of one-half of the [3]rotaxane and then of the other, a process that appears to be concerted at room temperature. The active form of the bistable [3]rotaxane bears disulfide tethers attached covalently to both of the CBPQT(4+) ring components for the purpose of its self-assembly onto a gold surface. An array of flexible microcantilever beams, each coated on one side with a monolayer of 6 billion of the active bistable [3]rotaxane molecules, undergoes controllable and reversible bending up and down when it is exposed to the synchronous addition of aqueous chemical oxidants and reductants. The beam bending is correlated with flexing of the surface-bound molecular muscles, whereas a monolayer of the dumbbell alone is inactive under the same conditions. This observation supports the hypothesis that the cumulative nanoscale movements within surface-bound "molecular muscles" can be harnessed to perform larger-scale mechanical work.

  15. Distribution of slow muscle fiber of muscle spindle in postnatal rat masseter muscle.

    PubMed

    Sato, Iwao; Imura, Kosuke; Miwa, Yoko; Ide, Yoshiaki; Murata, Megumi; Sunohara, Masataka

    2007-11-01

    We investigated the properties of the muscle spindle in the masseter muscle at an immunohistochemical level in rats fed for 6 weeks. Slow myosin heavy chain (MyHC) isoforms were measured and intrafusal fibers in the muscle spindle were studied to determine the relationship between the superficial and deep regions of rat masseter muscle after alternated feeding pattern. However, muscle spindles were found in both regions, mainly in the deep region of the posterior superficial region of masseter muscle. The total number of the slow fiber in the intrafusal fiber and number of muscle spindle in the deep region were high from 5 to 8 weeks old in spite of various dimensions of data such as diameter and the compositions of the intrafusal fiber. The relationship of the protein expression of slow MyHC in the two regions at 5 weeks old reversed five weeks later (10 weeks old). This period is an important stage because the mastication system in masseter muscle with muscle spindle may be changed during the alternated feeding pattern of suckling to mastication. The changes may be a marker of the feeding system and of the control by the tension receptor of muscle spindle in this stage of masseter muscle after postnatal development.

  16. Cranial muscles of the anurans Leiopelma hochstetteri and Ascaphus truei and the homologies of the mandibular adductors in Lissamphibia and other gnathostomes.

    PubMed

    Johnston, Peter

    2011-12-01

    The frogs Ascaphus truei and Leiopelma hochstetteri are members of the most basal lineages of extant anurans. Their cranial muscles have not been previously described in full and are investigated here by dissection. Comparison of these taxa is used to review a controversy regarding the homologies of the jaw adductor muscles in Lissamphibia, to place these homologies in a wider gnathostome context, and to define features that may be useful for cladistic analysis of Anura. A new muscle is defined in Ascaphus and is designated m. levator anguli oris. The differences noted between Ascaphus and Leiopelma are in the penetration of the jaw adductor muscles by the mandibular nerve (V3). In the traditional view of this anatomy, the paths of the trigeminal nerve branches define homologous muscles. This scheme results in major differences among frogs, salamanders, and caecilians. The alternative view is that the topology of origins, insertions, and fiber directions are defining features, and the nerves penetrate the muscle mass in a variable way. The results given here support the latter view. A new model is proposed for Lissamphibia, whereby the adductor posterior (levator articularis) is a separate entity, and the rest of the adductor mass is configured around it as a folded sheet. This hypothesis is examined in other gnathostomes, including coelacanth and lungfish, and a possible sequence for the evolution of the jaw muscles is demonstrated. In this system, the main jaw adductor in teleost fish is not considered homologous with that of tetrapods. This hypothesis is consistent with available data on the domain of expression of the homeobox gene engrailed 2, which has previously not been considered indicative of homology. Terminology is discussed, and "adductor mandibulae" is preferred to "levator mandibulae" to align with usage in other gnathostomes.

  17. Skeletal muscle satellite cells

    NASA Technical Reports Server (NTRS)

    Schultz, E.; McCormick, K. M.

    1994-01-01

    Evidence now suggests that satellite cells constitute a class of myogenic cells that differ distinctly from other embryonic myoblasts. Satellite cells arise from somites and first appear as a distinct myoblast type well before birth. Satellite cells from different muscles cannot be functionally distinguished from one another and are able to provide nuclei to all fibers without regard to phenotype. Thus, it is difficult to ascribe any significant function to establishing or stabilizing fiber type, even during regeneration. Within a muscle, satellite cells exhibit marked heterogeneity with respect to their proliferative behavior. The satellite cell population on a fiber can be partitioned into those that function as stem cells and those which are readily available for fusion. Recent studies have shown that the cells are not simply spindle shaped, but are very diverse in their morphology and have multiple branches emanating from the poles of the cells. This finding is consistent with other studies indicating that the cells have the capacity for extensive migration within, and perhaps between, muscles. Complexity of cell shape usually reflects increased cytoplasmic volume and organelles including a well developed Golgi, and is usually associated with growing postnatal muscle or muscles undergoing some form of induced adaptive change or repair. The appearance of activated satellite cells suggests some function of the cells in the adaptive process through elaboration and secretion of a product. Significant advances have been made in determining the potential secretion products that satellite cells make. The manner in which satellite cell proliferative and fusion behavior is controlled has also been studied. There seems to be little doubt that cellcell coupling is not how satellite cells and myofibers communicate. Rather satellite cell regulation is through a number of potential growth factors that arise from a number of sources. Critical to the understanding of this form

  18. [Delayed post effort muscle soreness].

    PubMed

    Coudreuse, J M; Dupont, P; Nicol, C

    2004-08-01

    Muscle intolerance to exercise may result from different processes. Diagnosis involves confirming first the source of pain, then potential pathological myalgia. Delayed-onset muscle soreness (DOMS), commonly referred as tiredness, occurs frequently in sport. DOMS usually develops 12-48 h after intensive and/or unusual eccentric muscle action. Symptoms usually involve the quadriceps muscle group but may also affect the hamstring and triceps surae groups. The muscles are sensitive to palpation, contraction and passive stretch. Acidosis, muscle spasm and microlesions in both connective and muscle tissues may explain the symptoms. However, inflammation appears to be the most common explanation. Interestingly, there is strong evidence that the progression of the exercise-induced muscle injury proceeds no further in the absence of inflammation. Even though unpleasant, DOMS should not be considered as an indicator of muscle damage but, rather, a sign of the regenerative process, which is well known to contribute to the increased muscle mass. DOMS can be associated with decreased proprioception and range of motion, as well as maximal force and activation. DOMS disappears 2-10 days before complete functional recovery. This painless period is ripe for additional joint injuries. Similarly, if some treatments are well known to attenuate DOMS, none has been demonstrated to accelerate either structural or functional recovery. In terms of the role of the inflammatory process, these treatments might even delay overall recovery.

  19. Ryanodine receptors in smooth muscle.

    PubMed

    Guerrero-Hernández, Agustín; Gómez-Viquez, Leticia; Guerrero-Serna, Guadalupe; Rueda, Angélica

    2002-07-01

    The sarcoplasmic reticulum (SR) of smooth muscle is endowed with two different types of Ca2+ release channels, i.e. inositol 1,4,5-trisphosphate receptors (IP3Rs) and ryanodine receptors (RyRs). In general, both release channels mobilize Ca2+ from the same internal store in smooth muscle. While the importance of IP3Rs in agonist-induced contraction is well established, the role of RyRs in excitation-contraction coupling of smooth muscle is not clear. The participation of smooth muscle RyRs in the amplification of Ca2+ transients induced by either opening of Ca2+-permeable channels or IP3-triggered Ca2+ release has been studied. The efficacy of both processes to activate RyRs by calcium-induced calcium release (CICR) is highly variable and not widely present in smooth muscle. Although RyRs in smooth muscle generate Ca2+ sparks that are similar to those observed in striated muscles, the contribution of these local Ca2+ events to depolarization-induced global rise in [Ca2+]i is rather limited. Recent data suggest that RyRs are involved in regulating the luminal [Ca2+] of SR and also in smooth muscle relaxation. This review summarizes studies that were carried out mainly in muscle strips or in freshly isolated myocytes, and that were aimed to determine the physiological role of RyRs in smooth muscle.

  20. Myositis ossificans traumatica of the masticatory muscles.

    PubMed

    Nemoto, Hitoshi; Sumiya, Noriyoshi; Ito, Yoshinori; Kimura, Naohiro; Akizuki, Ayako; Maruyama, Naoki

    2012-09-01

    Myositis ossificans traumatica (MOT) is a disease in which muscular ossification develops following trauma. Almost all cases of MOT are found in skeletal muscle. The authors report in a 39-year-old man MOT involving several muscles in the head and neck, namely, bilateral masseter muscles, the left temporal muscle, the left lateral pterygoid muscle, and the left frontal muscle. Involvement of the lateral pterygoid muscle is especially rare.

  1. Stretching Skeletal Muscle: Chronic Muscle Lengthening through Sarcomerogenesis

    PubMed Central

    Zöllner, Alexander M.; Abilez, Oscar J.; Böl, Markus; Kuhl, Ellen

    2012-01-01

    Skeletal muscle responds to passive overstretch through sarcomerogenesis, the creation and serial deposition of new sarcomere units. Sarcomerogenesis is critical to muscle function: It gradually re-positions the muscle back into its optimal operating regime. Animal models of immobilization, limb lengthening, and tendon transfer have provided significant insight into muscle adaptation in vivo. Yet, to date, there is no mathematical model that allows us to predict how skeletal muscle adapts to mechanical stretch in silico. Here we propose a novel mechanistic model for chronic longitudinal muscle growth in response to passive mechanical stretch. We characterize growth through a single scalar-valued internal variable, the serial sarcomere number. Sarcomerogenesis, the evolution of this variable, is driven by the elastic mechanical stretch. To analyze realistic three-dimensional muscle geometries, we embed our model into a nonlinear finite element framework. In a chronic limb lengthening study with a muscle stretch of 1.14, the model predicts an acute sarcomere lengthening from 3.09m to 3.51m, and a chronic gradual return to the initial sarcomere length within two weeks. Compared to the experiment, the acute model error was 0.00% by design of the model; the chronic model error was 2.13%, which lies within the rage of the experimental standard deviation. Our model explains, from a mechanistic point of view, why gradual multi-step muscle lengthening is less invasive than single-step lengthening. It also explains regional variations in sarcomere length, shorter close to and longer away from the muscle-tendon interface. Once calibrated with a richer data set, our model may help surgeons to prevent muscle overstretch and make informed decisions about optimal stretch increments, stretch timing, and stretch amplitudes. We anticipate our study to open new avenues in orthopedic and reconstructive surgery and enhance treatment for patients with ill proportioned limbs, tendon

  2. Accuracy and coverage assessment of Oryctolagus cuniculus (rabbit) genes encoding immunoglobulins in the whole genome sequence assembly (OryCun2.0) and localization of the IGH locus to chromosome 20.

    PubMed

    Gertz, E Michael; Schäffer, Alejandro A; Agarwala, Richa; Bonnet-Garnier, Amélie; Rogel-Gaillard, Claire; Hayes, Hélène; Mage, Rose G

    2013-10-01

    We report on the analyses of genes encoding immunoglobulin heavy and light chains in the rabbit 6.51× whole genome assembly. This OryCun2.0 assembly confirms previous mapping of the duplicated IGK1 and IGK2 loci to chromosome 2 and the IGL lambda light chain locus to chromosome 21. The most frequently rearranged and expressed IGHV1 that is closest to IG DH and IGHJ genes encodes rabbit VHa allotypes. The partially inbred Thorbecke strain rabbit used for whole-genome sequencing was homozygous at the IGK but heterozygous with the IGHV1a1 allele in one of 79 IGHV-containing unplaced scaffolds and IGHV1a2, IGHM, IGHG, and IGHE sequences in another. Some IGKV, IGLV, and IGHA genes are also in other unplaced scaffolds. By fluorescence in situ hybridization, we assigned the previously unmapped IGH locus to the q-telomeric region of rabbit chromosome 20. An approximately 3-Mb segment of human chromosome 14 including IGH genes predicted to map to this telomeric region based on synteny analysis could not be located on assembled chromosome 20. Unplaced scaffold chrUn0053 contains some of the genes that comparative mapping predicts to be missing. We identified discrepancies between previous targeted studies and the OryCun2.0 assembly and some new BAC clones with IGH sequences that can guide other studies to further sequence and improve the OryCun2.0 assembly. Complete knowledge of gene sequences encoding variable regions of rabbit heavy, kappa, and lambda chains will lead to better understanding of how and why rabbits produce antibodies of high specificity and affinity through gene conversion and somatic hypermutation.

  3. Organochlorines and heavy metals in wild caught food as a potential human health risk to the indigenous Māori population of South Canterbury, New Zealand.

    PubMed

    Stewart, Michael; Phillips, Ngaire R; Olsen, Greg; Hickey, Christopher W; Tipa, Gail

    2011-05-01

    Increasing concentrations of anthropogenic contaminants in wild kai (food) of cultural, recreational and economic importance to the indigenous Māori of New Zealand is a potential human health risk. Contaminants that are known to bioaccumulate through the food chain (e.g., organochlorine pesticides (OCPs), PCBs and selected heavy metals) were analysed in important kai species including eel (Anguilla sp.), brown trout (Salmo trutta), black flounder (Rhombosolea retiaria) and watercress (Nasturtium officinale) from important harvesting sites in the region of South Canterbury. Eels contained relatively high wet weight concentrations of p,p'-DDE (8.6-287ng/g), PCBs ((32)Σ(PCB); 0.53-58.3ng/g), dieldrin (<0.05-16.3ng/g) and Σchlordanes (0.03-10.6ng/g). Trout and flounder contained lower concentrations of organochlorines than eels, with p,p'-DDE wet weight concentrations ranging from 2.2 to 18.5ng/g for trout and 6.4 to 27.8ng/g for flounder. Total arsenic wet weight concentrations were below detection limits for eels but ranged from 0.27 to 0.89μg/g for trout and 0.12 to 0.56μg/g for flounder. Mercury concentrations ranged from 0.02 to 0.56μg/g, 0.11 to 0.50μg/g and 0.04 to 0.10μg/g (ww) for eel, trout and flounder respectively. Lifetime excess cancer risk was calculated through established risk assessment procedures, highlighting dieldrin, ΣPCBs and p,p'-DDE in eels and arsenic in trout and flounder as primary contaminants of concern. A second non-cancer chronic health risk assessment indicated that mercury and PCBs were a potential concern in eels and mercury in trout. A cumulative lifetime cancer risk assessment showed potential health risk for consumption of some species, even at low consumption rates and provided the basis for establishing recommended dietary consumption limits for harvest sites within the study region.

  4. U-Pb zircon and biostratigraphic data of high-pressure/low-temperature metamorphic rocks of the Talea Ori: tracking the Paleotethys suture in central Crete, Greece

    NASA Astrophysics Data System (ADS)

    Zulauf, G.; Dörr, W.; Krahl, J.; Lahaye, Y.; Chatzaras, V.; Xypolias, P.

    2016-10-01

    Inherited deformation microfabrics of detrital quartz grains and U-Pb (Laser ablation (LA)-ICPMS and ID TIMS) ages of detrital zircons separated from the Phyllite-Quartzite Unit s.l. of the Talea Ori, central Crete, suggest strikingly different source rocks. Albite gneiss of the lower Rogdia Beds includes Cambrian and Neoproterozoic rounded zircons with main U-Pb age peaks at 628 and 988 Ma. These and minor Paleoproterozoic and Archean peaks, together with the lack of Variscan-aged and Mesoproterozoic zircons, are similar to the age spectra obtained from the Phyllite-Quartzite Unit s.str. of the Peloponnesus and eastern Crete and from the Taurides. All of these zircons should be derived from the northeastern passive margin of Gondwana (Cimmeria). Metatuffites of the uppermost Rogdia Beds and metasandstone of Bali beach, on the other hand, include euhedral detrital zircons displaying a Variscan U-Pb age spectra at ca. 300 Ma with concordia ages at 291 ± 3, 300 ± 1 Ma (Rogdia) and 286 ± 3, 300 ± 3, 313 ± 2 Ma (Bali). Both types of metasediments and their zircons are similar to those of the pre-Alpine basement and overlying Tyros Beds of eastern Crete, revealing a provenance at the southern active margin of Laurasia. Thus, in central Crete the Paleotethys suture should be situated inside the Rogdia Beds. Magmatic zircons separated from a rhyolite boulder of the lower Achlada Beds yielded a concordant U-Pb zircon age at 242 ± 2 Ma placing a maximum age for the deposition of the (meta)conglomerate from which the boulder was collected. This age is compatible with an Olenekian-early Anisian age of the underlying Vasilikon marble suggested by new findings of the foraminifera Meandrospira aff. pusilla. Both the Achlada Beds and the Vasilikon marble can be attributed to the lower Tyros Beds of eastern Crete. The Alpine deformation led to a pervasive mylonitic foliation, which is affecting most of the studied rocks. This foliation results from D2 top

  5. Mining the HST "Advanced Spectral Library (ASTRAL)": Winds of the Evolved M Stars Alpha Ori (M2 Iab) and Gamma Cru (M3.4 III)

    NASA Astrophysics Data System (ADS)

    Carpenter, Kenneth G.; Nielsen, Krister E.; Kober, Gladys V.; Ayres, Thomas R.

    2015-01-01

    The "Advanced Spectral Library (ASTRAL) Project: Cool Stars" (PI = T. Ayres) is an HST Cycle 18 Treasury Program that collected a definitive set of representative, high-resolution (R=30,000-100,000) and high signal/noise (S/N>100) UV spectra of eight F-M evolved cool stars. These extremely high-quality STIS UV echelle spectra are available from the HST archive and through the ASTRAL website at the University of Colorado at http://casa.colorado.edu/~ayres/ASTRAL/ and will enable investigations of a broad range of problems -- stellar, interstellar, and beyond -- for many years. In this paper, we examine the wealth of wind diagnostics contained in the very rich spectra of the two evolved M stars in the sample, the M3.4 III giant Gamma Crucis (GaCrux) and the M2 Iab supergiant Alpha Orionis (Betelgeuse) and characterize the winds at the time of these STIS observations in 2011 and compare the results with those obtained from more limited data taken at earlier epochs with HST/GHRS and IUE. In particular we study the variation of the numerous Fe II profiles with intrinsic strength in the two stars. The shifting wavelengths of the wind absorptions relative to the emission peaks and the changes in relative strengths of the emission peaks reflect the acceleration of the wind from the base of the chromosphere. Although the characteristics of the Gamma Cru wind are relatively stable with time, the Alpha Ori wind outflow appears significantly smaller than seen by Carpenter et al. (1997, ApJ, 479, 970) in GHRS observations taken in 1992 (and in earlier IUE observations). There might in fact be evidence in these STIS spectra that the outflow has turned into an inflow, as reported at epochs prior to IUE by Boesgaard and Magnan (1975 ApJ 198, 369) and Boesgaard (1979 ApJ 232, 485) based on a limited number of lines in the extreme blue end of ground-based spectra.

  6. Paraspinal muscle reflex dynamics.

    PubMed

    Granata, K P; Slota, G P; Bennett, B C

    2004-02-01

    Neuromuscular control of spinal stability may be represented as a control system wherein the paraspinal muscle reflex acts as feedback response to kinetic and kinematic disturbances of the trunk. The influence of preparatory muscle recruitment for the control of spinal stability has been previously examined, but there are few reported studies that characterize paraspinal reflex gain as feedback response. In the current study, the input-output dynamics of paraspinal reflexes were quantified by means of the impulse response function (IRF), with trunk perturbation force representing the input signal and EMG the output signal. Surface EMGs were collected from the trunk muscles in response to a brief anteriorly directed impact force applied to the trunk of healthy participants. Reflex behavior was measured in response to three levels of force impulse, 6.1, 9.2 and 12.0 Ns, and two different levels of external trunk flexion preload, 0 and 110 N anterior force. Reflex EMG was quantifiable in response to 91% of the perturbations. Mean reflex onset latency was 30.7+/-21.3 ms and reflex amplitude increased with perturbation amplitude. Impulse response function gain, G(IRF), was defined as the peak amplitude of the measured IRF and provided a consistent measure of response behavior. EMG reflex amplitude and G(IRF) increased with force impulse. Mean G(IRF) was 2.27+/-1.31% MVC/Ns and demonstrated declining trend with flexion preload. Results agree with a simple systems model of the neuromechanical feedback behavior. The relative contribution of the reflex dynamics to spinal stability must be investigated in future research.

  7. Muscle dysmorphia: current insights

    PubMed Central

    Tod, David; Edwards, Christian; Cranswick, Ieuan

    2016-01-01

    Since 1997, there has been increasing research focusing on muscle dysmorphia, a condition underpinned by people’s beliefs that they have insufficient muscularity, in both the Western and non-Western medical and scientific communities. Much of this empirical interest has surveyed nonclinical samples, and there is limited understanding of people with the condition beyond knowledge about their characteristics. Much of the existing knowledge about people with the condition is unsurprising and inherent in the definition of the disorder, such as dissatisfaction with muscularity and adherence to muscle-building activities. Only recently have investigators started to explore questions beyond these limited tautological findings that may give rise to substantial knowledge advances, such as the examination of masculine and feminine norms. There is limited understanding of additional topics such as etiology, prevalence, nosology, prognosis, and treatment. Further, the evidence is largely based on a small number of unstandardized case reports and descriptive studies (involving small samples), which are largely confined to Western (North American, British, and Australian) males. Although much research has been undertaken since the term “muscle dysmorphia” entered the psychiatric lexicon in 1997, there remains tremendous scope for knowledge advancement. A primary task in the short term is for investigators to examine the extent to which the condition exists among well-defined populations to help determine the justification for research funding relative to other public health issues. A greater variety of research questions and designs may contribute to a broader and more robust knowledge base than currently exists. Future work will help clinicians assist a group of people whose quality of life and health are placed at risk by their muscular preoccupation. PMID:27536165

  8. New twist on artificial muscles

    PubMed Central

    Haines, Carter S.; Li, Na; Spinks, Geoffrey M.; Aliev, Ali E.; Di, Jiangtao; Baughman, Ray H.

    2016-01-01

    Lightweight artificial muscle fibers that can match the large tensile stroke of natural muscles have been elusive. In particular, low stroke, limited cycle life, and inefficient energy conversion have combined with high cost and hysteretic performance to restrict practical use. In recent years, a new class of artificial muscles, based on highly twisted fibers, has emerged that can deliver more than 2,000 J/kg of specific work during muscle contraction, compared with just 40 J/kg for natural muscle. Thermally actuated muscles made from ordinary polymer fibers can deliver long-life, hysteresis-free tensile strokes of more than 30% and torsional actuation capable of spinning a paddle at speeds of more than 100,000 rpm. In this perspective, we explore the mechanisms and potential applications of present twisted fiber muscles and the future opportunities and challenges for developing twisted muscles having improved cycle rates, efficiencies, and functionality. We also demonstrate artificial muscle sewing threads and textiles and coiled structures that exhibit nearly unlimited actuation strokes. In addition to robotics and prosthetics, future applications include smart textiles that change breathability in response to temperature and moisture and window shutters that automatically open and close to conserve energy. PMID:27671626

  9. New twist on artificial muscles.

    PubMed

    Haines, Carter S; Li, Na; Spinks, Geoffrey M; Aliev, Ali E; Di, Jiangtao; Baughman, Ray H

    2016-10-18

    Lightweight artificial muscle fibers that can match the large tensile stroke of natural muscles have been elusive. In particular, low stroke, limited cycle life, and inefficient energy conversion have combined with high cost and hysteretic performance to restrict practical use. In recent years, a new class of artificial muscles, based on highly twisted fibers, has emerged that can deliver more than 2,000 J/kg of specific work during muscle contraction, compared with just 40 J/kg for natural muscle. Thermally actuated muscles made from ordinary polymer fibers can deliver long-life, hysteresis-free tensile strokes of more than 30% and torsional actuation capable of spinning a paddle at speeds of more than 100,000 rpm. In this perspective, we explore the mechanisms and potential applications of present twisted fiber muscles and the future opportunities and challenges for developing twisted muscles having improved cycle rates, efficiencies, and functionality. We also demonstrate artificial muscle sewing threads and textiles and coiled structures that exhibit nearly unlimited actuation strokes. In addition to robotics and prosthetics, future applications include smart textiles that change breathability in response to temperature and moisture and window shutters that automatically open and close to conserve energy.

  10. Strabismus and eye muscle function.

    PubMed

    Lennerstrand, Gunnar

    2007-11-01

    Studies of external eye muscle morphology and physiology are reviewed, with respect to both motor and sensory functions in concomitant strabismus. The eye muscles have a more complex fibre composition than other striated muscle, and they are among the fastest and most fatigue-resistant muscles in the body. However, it is not generally believed that concomitant strabismus is due to a primary abnormality of the eye muscles or the ocular motor system. The gross anatomy of eye muscles, including the shape and position of the eye muscle pulleys, was not changed in strabismus. The histology of the eye muscle fibres was also basically the same, but changes have been observed in the cellular and biochemical machinery of the fibres, most notably in the singly innervated orbital fibres. Functionally, this was seen as slower contractions and reduced fatigue resistance of eye muscles in animals with strabismus and defects of binocular vision. Most likely the changes represented an adaptation to modified visual demands on the ocular motor control, because of the defects of binocular vision in strabismus from an early age. Adaptation of eye muscle function to visual demands could be seen also in the adult human ocular motor system, but here the effects could be reversed with treatment in some conditions. External eye muscles in the human have sensory organs, muscle spindles and tendon organs, responding to changes in muscle force and length. It is not known how these proprioceptors are used more specifically in ocular motor control, and there is no stretch reflex in the external eye muscles. However, a clear influence on space localization and eye position can be demonstrated with vibratory stimulation of the eye muscles, presumably activating muscle spindles. Different effects were observed in normal subjects and in adult patients with strabismus, which would indicate that the proprioceptive input from one eye of strabismic patients could be suppressed by the other eye, similar

  11. Muscle Stimulation Technology

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Under a Goddard Space Flight Center contract, Electrologic of America was able to refine the process of densely packing circuitry on personal computer boards, providing significant contributions to the closed-loop systems for the Remote Manipulator System Simulator. The microcircuitry work was then applied to the StimMaster FES Ergometer, an exercise device used to stimulate muscles suffering from paralysis. The electrical stimulation equipment was developed exclusively for V-Care Health Systems, Inc. Product still commercially available as of March 2002.

  12. The Interscutularis Muscle Connectome

    PubMed Central

    Lu, Ju; Tapia, Juan Carlos; White, Olivia L; Lichtman, Jeff W

    2009-01-01

    The complete connectional map (connectome) of a neural circuit is essential for understanding its structure and function. Such maps have only been obtained in Caenorhabditis elegans. As an attempt at solving mammalian circuits, we reconstructed the connectomes of six interscutularis muscles from adult transgenic mice expressing fluorescent proteins in all motor axons. The reconstruction revealed several organizational principles of the neuromuscular circuit. First, the connectomes demonstrate the anatomical basis of the graded tensions in the size principle. Second, they reveal a robust quantitative relationship between axonal caliber, length, and synapse number. Third, they permit a direct comparison of the same neuron on the left and right sides of the same vertebrate animal, and reveal significant structural variations among such neurons, which contrast with the stereotypy of identified neurons in invertebrates. Finally, the wiring length of axons is often longer than necessary, contrary to the widely held view that neural wiring length should be minimized. These results show that mammalian muscle function is implemented with a variety of wiring diagrams that share certain global features but differ substantially in anatomical form. This variability may arise from the dominant role of synaptic competition in establishing the final circuit. PMID:19209956

  13. Elicitability of muscle cramps in different leg and foot muscles.

    PubMed

    Minetto, Marco Alessandro; Botter, Alberto

    2009-10-01

    To explore the efficacy of muscle motor point stimulation in eliciting muscle cramps, 11 subjects underwent eight sessions of electrical stimulation of the following muscles bilaterally: abductor hallucis flexor hallucis brevis, and both heads of the gastrocnemius muscles. Bursts of 150 square wave stimuli (duration: 152 micros; current intensity: 30% supramaximal) were applied. The stimulation frequency was increased from 4 pulses per second (pps) at increments of 2 pps until a cramp was induced. The number of cramps that could be elicited was smaller in flexor hallucis brevis than in abductor hallucis (16 vs. 22 out of 22 trials each; P < 0.05) and in the lateral gastrocnemius than in the medial gastrocnemius (5 vs. 20 out of 22 trials each; P < 0.0001). We show that leg and foot muscles have different cramp susceptibility, and the intermuscle variability in the elicitability profile for electrically induced cramps supports the use of the proposed method for cramp research.

  14. Building Muscles, Keeping Muscles: Protein Turnover During Space Flight

    NASA Technical Reports Server (NTRS)

    Ferrando, Arny; Bloomberg, Jacob; Lee, Angie (Technical Monitor)

    2002-01-01

    As we age we lose muscle mass and strength. The problem is a matter of use it or lose it and more - a fact to which any active senior can attest. An imbalance in the natural cycle of protein turnover may be a contributing factor to decreased muscle mass. But the answer is not so simple, since aging is associated with changes in hormones, activity levels, nutrition, and often, disease. The human body constantly uses amino acids to build muscle protein, which then breaks down and must be replaced. When protein turnover gets out of balance, so that more protein breaks down than the body can replace, the result is muscle loss. This is not just the bane of aging, however. Severely burned people may have difficulty building new muscle long after the burned skin has been repaired. Answers to why we lose muscle mass and strength - and how doctors can fix it - may come from space. Astronauts usually eat a well-balanced diet and maintain an exercise routine to stay in top health. During long-duration flight, they exercise regularly to reduce the muscle loss that results from being in a near-weightless environment. Despite these precautions, astronauts lose muscle mass and strength during most missions. They quickly recover after returning to Earth - this is a temporary condition in an otherwise healthy population. Members of the STS-107 crew are participating in a study of the effects of space flight, hormone levels, and stress on protein turnover. When we are under stress, the body responds with a change in hormone levels. Researchers hypothesize that this stress-induced change in hormones along with the near-weightlessness might result in the body synthesizing less muscle protein, causing muscles to lose their strength and size. Astronauts, who must perform numerous duties in a confined and unusual environment, experience some stress during their flight, making them excellent candidates for testing the researchers' hypothesis.

  15. Caring for muscle spasticity or spasms

    MedlinePlus

    High muscle tone - care; Increased muscle tension - care; Upper motor neuron syndrome - care; Muscle stiffness - care ... and doing daily tasks. Talk with your health care provider or physical therapist first before starting any ...

  16. Trichinella spiralis in human muscle (image)

    MedlinePlus

    This is the parasite Trichinella spiralis in human muscle tissue. The parasite is transmitted by eating undercooked ... produce large numbers of larvae that migrate into muscle tissue. The cysts may cause muscle pain and ...

  17. Infraspinatus muscle atrophy from suprascapular nerve compression.

    PubMed

    Cordova, Christopher B; Owens, Brett D

    2014-02-01

    Muscle weakness without pain may signal a nerve compression injury. Because these injuries should be identified and treated early to prevent permanent muscle weakness and atrophy, providers should consider suprascapular nerve compression in patients with shoulder muscle weakness.

  18. Sternalis muscle: a mystery still.

    PubMed

    Loukas, Marios; Bowers, Maggi; Hullett, Joel

    2004-05-01

    Despite intensive anatomical research during the last century, anatomical structures or variations of these structures may still cause confusion or even iatrogenic injury. A matter of debate is the sternalis muscle. We present a review of the literature of the sternalis muscle with special emphasis on its clinical anatomy.

  19. Muscle tissue changes with aging.

    PubMed

    Pereira, Ana Fátima; Silva, António José; Matos Costa, Aldo; Monteiro, António Miguel; Bastos, Estela Maria; Cardoso Marques, Mário

    2013-01-01

    Sarcopenia is characterized by a progressive generalized decrease of skeletal muscle mass, strength and function with aging. Recently, the genetic determination has been associated with muscle mass and muscle strength in elderly. These two phenotypes of risk are the most commonly recognized and studied for sarcopenia, with heritability ranging from 30 to 85% for muscle strength and 45-90% for muscle mass. It is well known that the development and maintenance of muscle mass in early adulthood reduces the risk of developing sarcopenia and leads to a healthy aging. For that reason it seems important to identify which genetic factors interact with aging and in particular with the musculoskeletal response to exercise in such individuals. This review is designed to summarize the most important and representative studies about the possible association between certain genetic polymorphisms and muscle phenotypes in older populations. Also we will focuses on nutrition and some concerns associated with aging, including the role that exercise can have on reducing the negative effects of this phenomenon. Some results are inconsistent between studies and more replication studies underlying sarcopenia are needed, with larger samples and with different life cycles, particularly in the type and level of physical activity throughout life. In future we believe that further progress in understanding the genetic etiology and the metabolic pathways will provide valuable information on important biological mechanisms underlying the muscle physiology. This will enable better recognition of individuals at higher risk and the ability to more adequately address this debilitating condition.

  20. Fuel-powered artificial muscles.

    PubMed

    Ebron, Von Howard; Yang, Zhiwei; Seyer, Daniel J; Kozlov, Mikhail E; Oh, Jiyoung; Xie, Hui; Razal, Joselito; Hall, Lee J; Ferraris, John P; Macdiarmid, Alan G; Baughman, Ray H

    2006-03-17

    Artificial muscles and electric motors found in autonomous robots and prosthetic limbs are typically battery-powered, which severely restricts the duration of their performance and can necessitate long inactivity during battery recharge. To help solve these problems, we demonstrated two types of artificial muscles that convert the chemical energy of high-energy-density fuels to mechanical energy. The first type stores electrical charge and uses changes in stored charge for mechanical actuation. In contrast with electrically powered electrochemical muscles, only half of the actuator cycle is electrochemical. The second type of fuel-powered muscle provides a demonstrated actuator stroke and power density comparable to those of natural skeletal muscle and generated stresses that are over a hundred times higher.

  1. Aging changes in the bones - muscles - joints

    MedlinePlus

    Osteoporosis and aging; Muscle weakness associated with aging; Osteoarthritis ... Loss of muscle mass reduces strength. COMMON PROBLEMS Osteoporosis is a common problem, especially for older women. ...

  2. Complement activation promotes muscle inflammation during modified muscle use

    NASA Technical Reports Server (NTRS)

    Frenette, J.; Cai, B.; Tidball, J. G.

    2000-01-01

    Modified muscle use can result in muscle inflammation that is triggered by unidentified events. In the present investigation, we tested whether the activation of the complement system is a component of muscle inflammation that results from changes in muscle loading. Modified rat hindlimb muscle loading was achieved by removing weight-bearing from the hindlimbs for 10 days followed by reloading through normal ambulation. Experimental animals were injected with the recombinant, soluble complement receptor sCR1 to inhibit complement activation. Assays for complement C4 or factor B in sera showed that sCR1 produced large reductions in the capacity for activation of the complement system through both the classical and alternative pathways. Analysis of complement C4 concentration in serum in untreated animals showed that the classical pathway was activated during the first 2 hours of reloading. Analysis of factor B concentration in untreated animals showed activation of the alternative pathway at 6 hours of reloading. Administration of sCR1 significantly attenuated the invasion of neutrophils (-49%) and ED1(+) macrophages (-52%) that occurred in nontreated animals after 6 hours of reloading. The presence of sCR1 also reduced significantly the degree of edema by 22% as compared to untreated animals. Together, these data show that increased muscle loading activated the complement system which then briefly contributes to the early recruitment of inflammatory cells during modified muscle loading.

  3. Muscle type-specific myosin isoforms in crustacean muscles.

    PubMed

    LaFramboise, W A; Griffis, B; Bonner, P; Warren, W; Scalise, D; Guthrie, R D; Cooper, R L

    2000-01-01

    Differential expression of multiple myosin heavy chain (MyHC) genes largely determines the diversity of critical physiological, histochemical, and enzymatic properties characteristic of skeletal muscle. Hypotheses to explain myofiber diversity range from intrinsic control of expression based on myoblast lineage to extrinsic control by innervation, hormones, and usage. The unique innervation and specialized function of crayfish (Procambarus clarkii) appendicular and abdominal musculature provide a model to test these hypotheses. The leg opener and superficial abdominal extensor muscles are innervated by tonic excitatory motoneurons. High resolution SDS-PAGE revealed that these two muscles express the same MyHC profile. In contrast, the deep abdominal extensor muscles, innervated by phasic motoneurons, express MyHC profiles different from the tonic profiles. The claw closer muscles are dually innervated by tonic and phasic motoneurons and a mixed phenotype was observed, albeit biased toward the phasic profile seen in the closer muscle. These results indicate that multiple MyHC isoforms are present in the crayfish and that differential expression is associated with diversity of muscle type and function.

  4. Intermuscular pressure between synergistic muscles correlates with muscle force.

    PubMed

    Reinhardt, Lars; Siebert, Tobias; Leichsenring, Kay; Blickhan, Reinhard; Böl, Markus

    2016-08-01

    The purpose of the study was to examine the relationship between muscle force generated during isometric contractions (i.e. at a constant muscle-tendon unit length) and the intermuscular (between adjacent muscles) pressure in synergistic muscles. Therefore, the pressure at the contact area of the gastrocnemius and plantaris muscle was measured synchronously to the force of the whole calf musculature in the rabbit species Oryctolagus cuniculus Similar results were obtained when using a conductive pressure sensor, or a fibre-optic pressure transducer connected to a water-filled balloon. Both methods revealed a strong linear relationship between force and pressure in the ascending limb of the force-length relationship. The shape of the measured force-time and pressure-time traces was almost identical for each contraction (r=0.97). Intermuscular pressure ranged between 100 and 700 mbar (70,000 Pa) for forces up to 287 N. These pressures are similar to previous (intramuscular) recordings within skeletal muscles of different vertebrate species. Furthermore, our results suggest that the rise in intermuscular pressure during contraction may reduce the force production in muscle packages (compartments).

  5. Bulk muscles, loose cables

    PubMed Central

    Liyanage, Chamari R D G; Kodali, Venkata

    2014-01-01

    The accessibility and usage of body building supplements is on the rise with stronger internet marketing strategies by the industry. The dangers posed by the ingredients in them are underestimated. A healthy young man came to the emergency room with palpitations and feeling unwell. Initial history and clinical examination were non-contributory to find the cause. ECG showed atrial fibrillation. A detailed history for any over the counter or herbal medicine use confirmed that he was taking supplements to bulk muscle. One of the components in these supplements is yohimbine; the onset of symptoms coincided with the ingestion of this product and the patient is symptom free after stopping it. This report highlights the dangers to the public of consuming over the counter products with unknown ingredients and the consequential detrimental impact on health. PMID:25326558

  6. Molecular Signaling in Muscle Plasticity

    NASA Technical Reports Server (NTRS)

    Epstein, Henry F.

    1999-01-01

    Extended spaceflight under microgravity conditions leads to significant atrophy of weight-bearing muscles. Atrophy and hypertrophy are the extreme outcomes of the high degree of plasticity exhibited by skeletal muscle. Stimuli which control muscle plasticity include neuronal, hormonal, nutritional, and mechanical inputs. The mechanical stimulus for muscle is directly related to the work or exercise against a load performed. Little or no work is performed by weight-bearing muscles under microgravity conditions. A major hypothesis is that focal adhesion kinase (FAK) which is associated with integrin at the adherens junctions and costa meres of all skeletal muscles is an integral part of the major mechanism for molecular signaling upon mechanical stimulation in all muscle fibers. Additionally, we propose that myotonic protein kinase (DMPK) and dystrophin (DYSTR) also participate in distinct mechanically stimulated molecular signaling pathways that are most critical in type I and type II muscle fibers, respectively. To test these hypotheses, we will use the paradigms of hindlimb unloading and overloading in mice as models for microgravity conditions and a potential exercise countermeasure, respectively, in mice. We expect that FAK loss-of-function will impair hypertrophy and enhance atrophy in all skeletal muscle fibers whereas DYSTR and DMPK loss-of-function will have similar but more selective effects on Type IT and Type I fibers, respectively. Gene expression will be monitored by muscle-specific creatine kinase M promoter-reporter construct activity and specific MRNA and protein accumulation in the soleus (type I primarily) and plantaris (type 11 primarily) muscles. With these paradigms and assays, the following Specific Project Aims will be tested in genetically altered mice: 1) identify the roles of DYSTR and its pathway; 2) evaluate the roles of the DMPK and its pathway; 3) characterize the roles of FAK and its pathway and 4) genetically analyze the mechanisms

  7. Repairing skeletal muscle: regenerative potential of skeletal muscle stem cells

    PubMed Central

    Tedesco, Francesco Saverio; Dellavalle, Arianna; Diaz-Manera, Jordi; Messina, Graziella; Cossu, Giulio

    2010-01-01

    Skeletal muscle damaged by injury or by degenerative diseases such as muscular dystrophy is able to regenerate new muscle fibers. Regeneration mainly depends upon satellite cells, myogenic progenitors localized between the basal lamina and the muscle fiber membrane. However, other cell types outside the basal lamina, such as pericytes, also have myogenic potency. Here, we discuss the main properties of satellite cells and other myogenic progenitors as well as recent efforts to obtain myogenic cells from pluripotent stem cells for patient-tailored cell therapy. Clinical trials utilizing these cells to treat muscular dystrophies, heart failure, and stress urinary incontinence are also briefly outlined. PMID:20051632

  8. Factors in delayed muscle soreness.

    PubMed

    Abraham, W M

    1977-01-01

    The possible causes of delayed muscle soreness which occur 24 to 48 hr after exercise were examined from three different approaches, each designed to test an existing hypothesis. Surface electromyograms were used to evaluate the muscle spasm theory; the possibility of actual muscle cell damage was monitored by the presence of myoglobinuria, while the ratio of hydroxyproline/creatinine (OHP/Cr) in 24 hr urine collection was used as a marker for connective tissue involvement. In the first study, although all volunteers developed muscle soreness 24 and 48 hr after exercise, no change in the EMG activity of the sore muscles was observed. Myoglobin excretion was found in 88% of the subjects who developed soreness. However, in a second study, 92% of the subject who performed both moderate and heavy exercise but did not develop muscle soreness had myoglobinuria. In contrast, during a third experiment subjects on gelatin-free diets showed an increase (P less than .1) in the OHP/Cr between control (.020+/-.001) and 48 hr post-exercise (.002+/-.001, X+/-SE). Soreness resulted in all cases. When the OHP/Cr value is taken for the day of maximal soreness, the post-exercise mean increases to .024+/-.001 and the level of significance rises (P less than .005). These observations support the concept that exercise induced soreness may be related to disruption of the connective tissue elements in the muscle and/or their attachments.

  9. Epigenetic regulation of muscle development.

    PubMed

    Barreiro, Esther; Tajbakhsh, Shahragim

    2017-03-28

    In eukaryote cells, chromatin appears in several forms and is composed of genomic DNA, protein and RNA. The protein content of chromatin is composed primarily of core histones that are packaged into nucleosomes resulting in the condensation of the DNA. Several epigenetic mechanisms regulate the stability of the nucleosomes and the protein-protein interactions that modify the transcriptional activity of the DNA. Interestingly, epigenetic control of gene expression has recently emerged as a relevant mechanism involved in the regulation of many different biological processes including that of muscle development, muscle mass maintenance, function, and phenotype in health and disease. Recent investigations have shed light into the epigenetic control of biological mechanisms that are key regulators of embryonic muscle development and postnatal myogenesis. In the present review article, we provide a summary of the contents discussed in session 08, titled "Epigenetics of muscle regeneration", during the course of the 45th European Muscle Conference, which was celebrated in Montpellier (France) in September 2016. The main theme of that session was to highlight the most recent progress on the role of epigenetics in the regulation of muscle development and regeneration. The current mini-review has been divided into two major sections. On the one hand, a brief introduction on the topic of myogenesis is offered for the non-specialized reader. On the other, a brief overview of the most relevant epigenetic players that have been shown to control muscle development and regeneration is given.

  10. [Muscles and connective tissue: histology].

    PubMed

    Delage, J-P

    2012-10-01

    Here, we give some comments about the DVD movies "Muscle Attitudes" from Endovivo productions, the movies up lighting some loss in the attention given to studies on the connective tissue, and especially them into muscles. The main characteristics of the different components in the intra-muscular connective tissue (perimysium, endomysium, epimysium) are shown here with special references to their ordered architecture and special references to their spatial distributions. This connective tissue is abundant into the muscles and is in continuity with the muscles in vicinity, with their tendons and their sheath, sticking the whole on skin. This connective tissue has also very abundant connections on the muscles fibres. It is then assumed that the connective tissue sticks every organs or cells of the locomotion system. Considering the elastic properties of the collagen fibres which are the most abundant component of connective tissue, it is possible to up light a panel of connective tissue associated functions such as the transmission of muscle contractions or the regulation of protein and energetic muscles metabolism.

  11. Age-related changes in rat intrinsic laryngeal muscles: analysis of muscle fibers, muscle fiber proteins, and subneural apparatuses.

    PubMed

    Nishida, Naoya; Taguchi, Aki; Motoyoshi, Kazumi; Hyodo, Masamitsu; Gyo, Kiyofumi; Desaki, Junzo

    2013-03-01

    We compared age-related changes in the intrinsic laryngeal muscles of aged and young adult rats by determining the number and diameter of muscle fibers, contractile muscle protein (myosin heavy chain isoforms, MHC) composition, and the morphology of the subneural apparatuses. In aged rats, both the numbers and the diameters of muscle fibers decreased in the cricothyroid (CT) muscle. The number of fibers, but not diameter, decreased in the thyroarytenoid (TA) muscle. In the posterior cricoarytenoid (PCA) muscle, neither the number nor the diameter of fibers changed significantly. Aging was associated with a decrease in type IIB and an increase in type IIA MHC isoform levels in CT muscle, but no such changes were observed in the TA or PCA muscles. Morphological examination of primary synaptic clefts of the subneural apparatus revealed that aging resulted in decreased labyrinthine and increased depression types in only the CT muscle. In the aged group, morphologically immature subneural apparatuses were found infrequently in the CT muscle, indicating continued tissue remodeling. We suggest, therefore, that age-related changes in the intrinsic laryngeal muscles primarily involve the CT muscle, whereas the structures of the TA and PCA muscles may better resist aging processes and therefore are less vulnerable to functional impairment. This may reflect differences in their roles; the CT muscle controls the tone of the vocal folds, while the TA and PCA muscles play an essential role in vital activities such as respiration and swallowing.

  12. Eccentric muscle challenge shows osteopontin polymorphism modulation of muscle damage.

    PubMed

    Barfield, Whitney L; Uaesoontrachoon, Kitipong; Wu, Chung-Sheih; Lin, Stephen; Chen, Yue; Wang, Paul C; Kanaan, Yasmine; Bond, Vernon; Hoffman, Eric P

    2014-08-01

    A promoter polymorphism of the osteopontin (OPN) gene (rs28357094) has been associated with multiple inflammatory states, severity of Duchenne muscular dystrophy (DMD) and muscle size in healthy young adults. We sought to define the mechanism of action of the polymorphism, using allele-specific in vitro reporter assays in muscle cells, and a genotype-stratified intervention in healthy controls. In vitro reporter constructs showed the G allele to respond to estrogen treatment, whereas the T allele showed no transcriptional response. Young adult volunteers (n = 187) were enrolled into a baseline study, and subjects with specific rs28357094 genotypes enrolled into an eccentric muscle challenge intervention [n = 3 TT; n = 3 GG/GT (dominant inheritance model)]. Female volunteers carrying the G allele showed significantly greater inflammation and increased muscle volume change as determined by magnetic resonance imaging T1- and T2-weighted images after eccentric challenge, as well as greater decrement in biceps muscle force. Our data suggest a model where the G allele enables enhanced activities of upstream enhancer elements due to loss of Sp1 binding at the polymorphic site. This results in significantly greater expression of the pro-inflammatory OPN cytokine during tissue remodeling in response to challenge in G allele carriers, promoting muscle hypertrophy in normal females, but increased damage in DMD patients.

  13. Stochastic modelling of muscle recruitment during activity

    PubMed Central

    Martelli, Saulo; Calvetti, Daniela; Somersalo, Erkki; Viceconti, Marco

    2015-01-01

    Muscle forces can be selected from a space of muscle recruitment strategies that produce stable motion and variable muscle and joint forces. However, current optimization methods provide only a single muscle recruitment strategy. We modelled the spectrum of muscle recruitment strategies while walking. The equilibrium equations at the joints, muscle constraints, static optimization solutions and 15-channel electromyography (EMG) recordings for seven walking cycles were taken from earlier studies. The spectrum of muscle forces was calculated using Bayesian statistics and Markov chain Monte Carlo (MCMC) methods, whereas EMG-driven muscle forces were calculated using EMG-driven modelling. We calculated the differences between the spectrum and EMG-driven muscle force for 1–15 input EMGs, and we identified the muscle strategy that best matched the recorded EMG pattern. The best-fit strategy, static optimization solution and EMG-driven force data were compared using correlation analysis. Possible and plausible muscle forces were defined as within physiological boundaries and within EMG boundaries. Possible muscle and joint forces were calculated by constraining the muscle forces between zero and the peak muscle force. Plausible muscle forces were constrained within six selected EMG boundaries. The spectrum to EMG-driven force difference increased from 40 to 108 N for 1–15 EMG inputs. The best-fit muscle strategy better described the EMG-driven pattern (R2 = 0.94; RMSE = 19 N) than the static optimization solution (R2 = 0.38; RMSE = 61 N). Possible forces for 27 of 34 muscles varied between zero and the peak muscle force, inducing a peak hip force of 11.3 body-weights. Plausible muscle forces closely matched the selected EMG patterns; no effect of the EMG constraint was observed on the remaining muscle force ranges. The model can be used to study alternative muscle recruitment strategies in both physiological and pathophysiological neuromotor conditions. PMID:25844155

  14. Skeletal Muscle Hypertrophy after Aerobic Exercise Training

    PubMed Central

    Konopka, Adam R.; Harber, Matthew P.

    2014-01-01

    Current dogma suggests aerobic exercise training has minimal effect on skeletal muscle size. We and others have demonstrated that aerobic exercise acutely and chronically alters protein metabolism and induces skeletal muscle hypertrophy. These findings promote an antithesis to the status quo by providing novel perspective on skeletal muscle mass regulation and insight into exercise-countermeasures for populations prone to muscle loss. PMID:24508740

  15. Compensatory Hypertrophy of Skeletal Muscle: Contractile Characteristics

    ERIC Educational Resources Information Center

    Ianuzzo, C. D.; Chen, V.

    1977-01-01

    Describes an experiment using rats that demonstrates contractile characteristics of normal and hypertrophied muscle. Compensatory hypertrophy of the plantaris muscle is induced by surgical removal of the synergistic gastrocnemium muscle. Includes methods for determination of contractile properties of normal and hypertrophied muscle and…

  16. Medicines to Treat Muscle Spasms and Pain

    MedlinePlus

    Medicines to Treat Muscle Spasms and Pain Do you have a lot of muscle pain? Are your muscles extremely stiff and tense? If the answer is ... factsheet to learn about two conditions that cause muscle pain and stiffness, and the medicines used to ...

  17. Hypodynamic and hypokinetic condition of skeletal muscles

    NASA Technical Reports Server (NTRS)

    Katinas, G. S.; Oganov, V. S.; Potapov, A. N.

    1980-01-01

    Data are presented in regard to the effect of unilateral brachial amputation on the physiological characteristics of two functionally different muscles, the brachial muscle (flexor of the brachium) and the medial head of the brachial triceps muscle (extensor of the brachium), which in rats represents a separate muscle. Hypokinesia and hypodynamia were studied.

  18. Heterogeneous ageing of skeletal muscle microvascular function.

    PubMed

    Muller-Delp, Judy M

    2016-04-15

    The distribution of blood flow to skeletal muscle during exercise is altered with advancing age. Changes in arteriolar function that are muscle specific underlie age-induced changes in blood flow distribution. With advancing age, functional adaptations that occur in resistance arterioles from oxidative muscles differ from those that occur in glycolytic muscles. Age-related adaptations of morphology, as well as changes in both endothelial and vascular smooth muscle signalling, differ in muscle of diverse fibre type. Age-induced endothelial dysfunction has been reported in most skeletal muscle arterioles; however, unique alterations in signalling contribute to the dysfunction in arterioles from oxidative muscles as compared with those from glycolytic muscles. In resistance arterioles from oxidative muscle, loss of nitric oxide signalling contributes significantly to endothelial dysfunction, whereas in resistance arterioles from glycolytic muscle, alterations in both nitric oxide and prostanoid signalling underlie endothelial dysfunction. Similarly, adaptations of the vascular smooth muscle that occur with advancing age are heterogeneous between arterioles from oxidative and glycolytic muscles. In both oxidative and glycolytic muscle, late-life exercise training reverses age-related microvascular dysfunction, and exercise training appears to be particularly effective in reversing endothelial dysfunction. Patterns of microvascular ageing that develop among muscles of diverse fibre type and function may be attributable to changing patterns of physical activity with ageing. Importantly, aerobic exercise training, initiated even at an advanced age, restores muscle blood flow distribution patterns and vascular function in old animals to those seen in their young counterparts.

  19. Pelvic floor muscle training exercises

    MedlinePlus

    ... nlm.nih.gov/pubmed/22258946 . Dumoulin C, Hay-Smith J. Pelvic floor muscle training versus no treatment, ... nlm.nih.gov/pubmed/20091581 . Herderschee R, Hay-Smith EJC, Herbison GP, Roovers JP, Heineman MJ. Feedback ...

  20. Knitting and weaving artificial muscles

    PubMed Central

    Maziz, Ali; Concas, Alessandro; Khaldi, Alexandre; Stålhand, Jonas; Persson, Nils-Krister; Jager, Edwin W. H.

    2017-01-01

    A need exists for artificial muscles that are silent, soft, and compliant, with performance characteristics similar to those of skeletal muscle, enabling natural interaction of assistive devices with humans. By combining one of humankind’s oldest technologies, textile processing, with electroactive polymers, we demonstrate here the feasibility of wearable, soft artificial muscles made by weaving and knitting, with tunable force and strain. These textile actuators were produced from cellulose yarns assembled into fabrics and coated with conducting polymers using a metal-free deposition. To increase the output force, we assembled yarns in parallel by weaving. The force scaled linearly with the number of yarns in the woven fabric. To amplify the strain, we knitted a stretchable fabric, exhibiting a 53-fold increase in strain. In addition, the textile construction added mechanical stability to the actuators. Textile processing permits scalable and rational production of wearable artificial muscles, and enables novel ways to design assistive devices. PMID:28138542

  1. Aging of skeletal muscle fibers.

    PubMed

    Miljkovic, Natasa; Lim, Jae-Young; Miljkovic, Iva; Frontera, Walter R

    2015-04-01

    Aging has become an important topic for scientific research because life expectancy and the number of men and women in older age groups have increased dramatically in the last century. This is true in most countries of the world including the Republic of Korea and the United States. From a rehabilitation perspective, the most important associated issue is a progressive decline in functional capacity and independence. Sarcopenia is partly responsible for this decline. Many changes underlying the loss of muscle mass and force-generating capacity of skeletal muscle can be understood at the cellular and molecular levels. Muscle size and architecture are both altered with advanced adult age. Further, changes in myofibers include impairments in several physiological domains including muscle fiber activation, excitation-contraction coupling, actin-myosin cross-bridge interaction, energy production, and repair and regeneration. A thorough understanding of these alterations can lead to the design of improved preventative and rehabilitative interventions, such as personalized exercise training programs.

  2. Types of muscle tissue (image)

    MedlinePlus

    ... appear striated, and are under involuntary control. Smooth muscle fibers are located in walls of hollow visceral organs, except the heart, appear spindle-shaped, and are also under involuntary control. Skeletal ...

  3. [Acute muscle weakness: differential diagnoses].

    PubMed

    Antoniuk, Sérgio A

    2013-09-06

    Acute muscle weakness, a common disorder in pediatrics, can occur from impairment of any part of the motor unit, including the upper motor neuron, lower motor neuron, peripheral nerve, neuromuscular junction or muscle. It usually manifests itself as an acute or hyperacute motor disorder of progressive or rapidly progressive course. Acute muscle weakness is a neuromuscular emergency, especially if it affects the respiratory or oropharyngeal musculature. The location of the motor weakness and associated neurological signs and symptoms usually indicate the location of the lesion. The onset, speed and clinical evolution, as well as other data from the patient's history, suggest the pathophysiological differential diagnosis. Successful treatment depends on the immediate and correct differential diagnosis. This paper presents the main differential diagnosis of main neuromuscular diseases that cause acute muscle weakness in children.

  4. The Mechanochemistry of Cardiac Muscle

    PubMed Central

    Pool, Peter E.; Sonnenblick, Edmund H.

    1967-01-01

    The utilization of creatine phosphate (CP) and adenosine triphosphate (ATP) was studied in the iodoacetate (IAA) and nitrogen (N2)-treated cat papillary muscle. Under these conditions the net production of ATP does not occur, and the net utilization of ATP is reflected in a fall in CP concentration. The rate of energy utilization of the IAA-N2-treated cat papillary muscle resting without tension was 0.68 µmole CP/g/min. This rate was increased to 1.07 µmole/g/min when muscles were passively stretched with 2 g of tension. In a series of isometrically contracting muscles CP utilization was found to be proportional to the number of activations and the summated contractile element work. These rates of CP utilization were 0.083 µmole/g/activation and 0.0059 µmole/g-cm of work. The calculated mechanochemical coupling efficiency was 33%. PMID:6034511

  5. Knitting and weaving artificial muscles.

    PubMed

    Maziz, Ali; Concas, Alessandro; Khaldi, Alexandre; Stålhand, Jonas; Persson, Nils-Krister; Jager, Edwin W H

    2017-01-01

    A need exists for artificial muscles that are silent, soft, and compliant, with performance characteristics similar to those of skeletal muscle, enabling natural interaction of assistive devices with humans. By combining one of humankind's oldest technologies, textile processing, with electroactive polymers, we demonstrate here the feasibility of wearable, soft artificial muscles made by weaving and knitting, with tunable force and strain. These textile actuators were produced from cellulose yarns assembled into fabrics and coated with conducting polymers using a metal-free deposition. To increase the output force, we assembled yarns in parallel by weaving. The force scaled linearly with the number of yarns in the woven fabric. To amplify the strain, we knitted a stretchable fabric, exhibiting a 53-fold increase in strain. In addition, the textile construction added mechanical stability to the actuators. Textile processing permits scalable and rational production of wearable artificial muscles, and enables novel ways to design assistive devices.

  6. Electrically controllable artificial PAN muscles

    NASA Astrophysics Data System (ADS)

    Salehpoor, Karim; Shahinpoor, Mohsen; Mojarrad, Mehran

    1996-02-01

    Artificial muscles made with polyacrylonitrile (PAN) fibers are traditionally activated in electrolytic solution by changing the pH of the solution by the addition of acids and/or bases. This usually consumes a considerable amount of weak acids or bases. Furthermore, the synthetic muscle (PAN) itself has to be impregnated with an acid or a base and must have an appropriate enclosure or provision for waste collection after actuation. This work introduces a method by which the PAN muscle may be elongated or contracted in an electric field. We believe this is the first time that this has been achieved with PAN fibers as artificial muscles. In this new development the PAN muscle is first put in close contact with one of the two platinum wires (electrodes) immersed in an aqueous solution of sodium chloride. Applying an electric voltage between the two wires changes the local acidity of the solution in the regions close to the platinum wires. This is because of the ionization of sodium chloride molecules and the accumulation of Na+ and Cl- ions at the negative and positive electrode sites, respectively. This ion accumulation, in turn, is accompanied by a sharp increase and decrease of the local acidity in regions close to either of the platinum wires, respectively. An artificial muscle, in close contact with the platinum wire, because of the change in the local acidity will contract or expand depending on the polarity of the electric field. This scheme allows the experimenter to use a fixed flexible container of an electrolytic solution whose local pH can be modulated by an imposed electric field while the produced ions are basically trapped to stay in the neighborhood of a given electrode. This method of artificial muscle activation has several advantages. First, the need to use a large quantity of acidic or alkaline solutions is eliminated. Second, the use of a compact PAN muscular system is facilitated for applications in active musculoskeletal structures. Third, the

  7. Myomaker is essential for muscle regeneration.

    PubMed

    Millay, Douglas P; Sutherland, Lillian B; Bassel-Duby, Rhonda; Olson, Eric N

    2014-08-01

    Regeneration of injured adult skeletal muscle involves fusion of activated satellite cells to form new myofibers. Myomaker is a muscle-specific membrane protein required for fusion of embryonic myoblasts, but its potential involvement in adult muscle regeneration has not been explored. We show that myogenic basic helix-loop-helix (bHLH) transcription factors induce myomaker expression in satellite cells during acute and chronic muscle regeneration. Moreover, genetic deletion of myomaker in adult satellite cells completely abolishes muscle regeneration, resulting in severe muscle destruction after injury. Myomaker is the only muscle-specific protein known to be absolutely essential for fusion of embryonic and adult myoblasts.

  8. Myomaker is essential for muscle regeneration

    PubMed Central

    Millay, Douglas P.; Sutherland, Lillian B.; Bassel-Duby, Rhonda

    2014-01-01

    Regeneration of injured adult skeletal muscle involves fusion of activated satellite cells to form new myofibers. Myomaker is a muscle-specific membrane protein required for fusion of embryonic myoblasts, but its potential involvement in adult muscle regeneration has not been explored. We show that myogenic basic helix–loop–helix (bHLH) transcription factors induce myomaker expression in satellite cells during acute and chronic muscle regeneration. Moreover, genetic deletion of myomaker in adult satellite cells completely abolishes muscle regeneration, resulting in severe muscle destruction after injury. Myomaker is the only muscle-specific protein known to be absolutely essential for fusion of embryonic and adult myoblasts. PMID:25085416

  9. Evaluation of muscle hyperactivity of the grimacing muscles by unilateral tight eyelid closure and stapedius muscle tone.

    PubMed

    Shiba, Masato; Matsuo, Kiyoshi; Ban, Ryokuya; Nagai, Fumio

    2012-10-01

    Muscle hyperactivity of grimacing muscles, including the orbicularis oculi and corrugator supercilii muscles that cause crow's feet and a glabellar frown line with ageing, cannot be accurately evaluated by surface observation. In 71 subjects, this study investigated the extent to which grimacing muscles are innervated by the bilateral motor cortices, whether the corticofacial projection to the grimacing muscles affects the facially innervated stapedius muscle tone by measuring static compliance of the tympanic membrane, and whether unilateral tight eyelid closure with contraction of the grimacing muscles changes static compliance. Unilateral tight eyelid closure and its subsequent change in the contralateral vertical medial eyebrow position revealed that motor neurons of the orbicularis oculi and corrugator supercilii muscles were innervated by the bilateral motor cortices with weak-to-strong contralateral dominance. The orbicularis oculi, corrugator supercilii, and stapedius muscles innervated by the bilateral motor cortices had increased muscle hyperactivity, which lowered the vertical medial eyebrow position and decreased the static compliance of the tympanic membrane more than those innervated by the unilateral motor cortex. Unilateral enhanced tight eyelid closure with contraction of the grimacing muscles in certain subjects ipsilaterally decreased the static compliance with increased contraction of the stapedius muscle, which probably occurs to immobilise the tympanic membrane and protect the inner ear from loud sound. Evaluation of unilateral tight eyelid closure and the subsequent change in the contralateral vertical medial eyebrow position as well as a measurement of the static compliance for the stapedius muscle tone has revealed muscle hyperactivity of grimacing muscles.

  10. Amyloidotic muscle pseudohypertrophy: case report.

    PubMed

    Scola, R H; Werneck, L C; Ramos, C S; Pasquini, R; Graf, H; Arruda, W O

    2001-09-01

    The authors report one case of amyloidosis associated with muscular pseudohypertrophy in a 46-year-old woman, who developed weakness, macroglossia and muscle hypertrophy associated with primary systemic amyloidosis. Electromyography showed a myopathic pattern and bilateral carpal tunnel syndrome. The muscle biopsy presented with a type I and II fiber hypertrophy and infiltration of amyloid material in the interstitious space and artery walls. She underwent bone marrow transplantation with stabilization and subjective improvement of the clinical picture.

  11. Factors contributing to thixotropy of inspiratory muscles.

    PubMed

    Izumizaki, Masahiko; Shibata, Masahiko; Homma, Ikuo

    2004-06-25

    Thixotropy is a passive property of the skeletal muscle dependent on the muscle's immediate history of contraction and length change. Thixotropic properties of inspiratory muscles, introduced by forceful muscle contraction at an inflated lung volume, cause an increased end-expiratory position (EEP) of the rib cage. We searched for factors contributing to the development of inspiratory muscle thixotropy in nine healthy subjects. Using induction plethysmography, we examined aftereffects on EEP of the duration of inspiratory muscle contraction and subsequent muscle relaxation. We also studied effects of inspiratory effort intensity measured by mouth pressure at different lung volumes. EEP elevation was noted subsequent to 5-s contraction followed by 2-s relaxation and was enhanced when conditioned at higher lung volumes with a strong inspiratory effort. Our results suggest four factors that influence inspiratory muscle thixotropy: (1) intensity of muscle contraction, (2) lung volume when contraction occurs, (3) duration of contraction, and (4) muscle relaxation.

  12. Artificial muscle: facts and fiction.

    PubMed

    Schaub, Marcus C

    2011-12-19

    Mechanical devices are sought to support insufficient or paralysed striated muscles including the failing heart. Nickel-titanium alloys (nitinol) present the following two properties: (i) super-elasticity, and (ii) the potential to assume different crystal structures depending on temperature and/or stress. Starting from the martensite state nitinol is able to resume the austenite form (state of low potential energy and high entropy) even against an external resistance. This one-way shape change is deployed in self-expanding vascular stents. Heating induces the force generating transformation from martensite to the austenite state while cooling induces relaxation back to the martensite state. This two-way shape change oscillating between the two states may be used in cyclically contracting support devices of silicon-coated nitinol wires. Such a contractile device sutured to the right atrium has been tested in vitro in a bench model and in vivo in sheep. The contraction properties of natural muscles, specifically of the myocardium, and the tight correlation with ATP production by oxidative phosphorylation in the mitochondria is briefly outlined. Force development by the nitinol device cannot be smoothly regulated as in natural muscle. Its mechanical impact is forced onto the natural muscle regardless of the actual condition with regard to metabolism and Ca2+-homeostasis. The development of artificial muscle on the basis of nitinol wires is still in its infancy. The nitinol artificial muscle will have to prove its viability in the various clinical settings.

  13. Satellite cells: the architects of skeletal muscle.

    PubMed

    Chang, Natasha C; Rudnicki, Michael A

    2014-01-01

    The outstanding regenerative capacity of skeletal muscle is attributed to the resident muscle stem cell termed satellite cell. Satellite cells are essential for skeletal muscle regeneration as they ultimately provide the myogenic precursors that rebuild damaged muscle tissue. Satellite cells characteristically are a heterogeneous population of stem cells and committed progenitor cells. Delineation of cellular hierarchy and understanding how lineage fate choices are determined within the satellite cell population will be invaluable for the advancement of muscle regenerative therapies.

  14. Effect of acupuncture depth on muscle pain

    PubMed Central

    2011-01-01

    Background While evidence supports efficacy of acupuncture and/or dry needling in treating musculoskeletal pain, it is unclear which needling method is most effective. This study aims to determine the effects of depth of needle penetration on muscle pain. Methods A total of 22 healthy volunteers performed repeated eccentric contractions to induce muscle soreness in their extensor digital muscle. Subjects were assigned randomly to four groups, namely control group, skin group (depth of 3 mm: the extensor digital muscle), muscle group (depth of 10 mm: the extensor digital muscle) and non-segmental group (depth of 10 mm: the anterior tibial muscle). Pressure pain threshold and electrical pain threshold of the skin, fascia and muscle were measured at a point 20 mm distal to the maximum tender point on the second day after the exercise. Results Pressure pain thresholds of skin group (depth of 3 mm: the extensor digital muscle) and muscle group (depth of 10 mm: the extensor digital muscle) were significantly higher than the control group, whereas the electrical pain threshold at fascia of muscle group (depth of 10 mm: the extensor digital muscle) was a significantly higher than control group; however, there was no significant difference between the control and other groups. Conclusion The present study shows that acupuncture stimulation of muscle increases the PPT and EPT of fascia. The depth of needle penetration is important for the relief of muscle pain. PMID:21696603

  15. Automated recognition of the iliac muscle and modeling of muscle fiber direction in torso CT images

    NASA Astrophysics Data System (ADS)

    Kamiya, N.; Zhou, X.; Azuma, K.; Muramatsu, C.; Hara, T.; Fujita, H.

    2016-03-01

    The iliac muscle is an important skeletal muscle related to ambulatory function. The muscles related to ambulatory function are the psoas major and iliac muscles, collectively defined as the iliopsoas muscle. We have proposed an automated recognition method of the iliac muscle. Muscle fibers of the iliac muscle have a characteristic running pattern. Therefore, we used 20 cases from a training database to model the movement of the muscle fibers of the iliac muscle. In the recognition process, the existing position of the iliac muscle was estimated by applying the muscle fiber model. To generate an approximation mask by using a muscle fiber model, a candidate region of the iliac muscle was obtained. Finally, the muscle region was identified by using values from the gray value and boundary information. The experiments were performed by using the 20 cases without abnormalities in the skeletal muscle for modeling. The recognition result in five cases obtained a 76.9% average concordance rate. In the visual evaluation, overextraction of other organs was not observed in 85% of the cases. Therefore, the proposed method is considered to be effective in the recognition of the initial region of the iliac muscle. In the future, we will integrate the recognition method of the psoas major muscle in developing an analytical technique for the iliopsoas area. Furthermore, development of a sophisticated muscle function analysis method is necessary.

  16. Pelvic muscles during rest: responses to pelvic muscle exercise.

    PubMed

    Griffin, C; Dougherty, M C; Yarandi, H

    1994-01-01

    The purpose of the research was to study pelvic muscle changes in the resting phase between voluntary contractions (during pelvic muscle assessment) and in response to pelvic muscle exercise (PME) through secondary analysis of data. The sample consisted of healthy women (N = 38) aged 35 to 54. Analysis of variance showed a significant difference in resting pressure within each assessment (F = 2.92, p < .04). A significant difference in resting pressures within subjects was found (F = 3.54, p < .02). Within-subject variance suggests exercises performed without a warmup may result in incomplete relaxation prior to contraction. Significant change between baseline and Level 1 of the graded PME program suggests slow relaxation of untrained muscles. Increases in resting pressure at Levels 3 and 4 may be a more accurate reflection of muscle hypertrophy. The results of this research indicate that care should be taken in establishing the point from which changes during contractions are measured. It is recommended that the resting pressure be used. Exercise continued for more than 3 or 4 weeks accounts for nearly all strength gains and explains the increases in resting pressure at PME Levels 3 and 4.

  17. [Regeneration capacity of skeletal muscle].

    PubMed

    Wernig, A

    2003-07-01

    The organotypic stem cell of skeletal muscle has previously been known as satellite cell. They allow muscle fiber growth during ontogenesis, enable fiber hypertrophy and are responsible for the very efficient repair of muscle fibers. This efficient apparatus is to some degree counterbalanced by an enormous use of the satellite cell pool: fiber atrophy probably is accompanied by loss of myonuclei such that every reversal of atrophy is bound to use new myonuclei i.e. satellite cells. How often in life does this occur? Hard to say. Moreover, the potent repair capacity is challenged by an unexpected vulnerability of skeletal muscle fibers: Passive stretching of contracted muscles may cause multiple "microdamage," disruption of contractile elements or tiny areas of true necrosis (focal necrosis). How often does this happen? Well, for many of us at least once per year when we go up and down mountains during vacation time, followed by sour muscles. Others may decide to change his/her (locomotor) behaviour by severe onset of jogging; it may happen that they suffer kidney failure on Monday due to muscle microdamage and the transfer of myoproteins into the serum over weekend. Also 20 minutes of stepping up and down something like a chair will do: There is a remarkable increase in kreatin kinase and other muscle derived proteins which lasts for days and is bound to reflect some muscle damage. How about sportsmen and worker who repeatedly use their muscles in such a way? We don't have answers yet to most of these questions, but considerable amount of information has been collected over the last years both in animal and--less--in human. What is common in all cases of growth and repair is the proliferation of the satellite cells and their consequent incorporation and fusion with the parent fiber. This way focal damage is repaired often without visible reminders. We would run out of satellite cells were they not stem cells: After division one daughter remains a satellite cell

  18. Laughing: a demanding exercise for trunk muscles.

    PubMed

    Wagner, Heiko; Rehmes, Ulrich; Kohle, Daniel; Puta, Christian

    2014-01-01

    Social, psychological, and physiological studies have provided evidence indicating that laughter imposes an increased demand on trunk muscles. It was the aim of this study to quantify the activation of trunk muscles during laughter yoga in comparison with crunch and back lifting exercises regarding the mean trunk muscle activity. Muscular activity during laughter yoga exercises was measured by surface electromyography of 5 trunk muscles. The activation level of internal oblique muscle during laughter yoga is higher compared to the traditional exercises. The multifidus, erector spinae, and rectus abdominis muscles were nearly half activated during laughter yoga, while the activation of the external oblique muscle was comparable with the crunch and back lifting exercises. Our results indicate that laughter yoga has a positive effect on trunk muscle activation. Thus, laughter seems to be a good activator of trunk muscles, but further research is required whether laughter yoga is a good exercise to improve neuromuscular recruitment patterns for spine stability.

  19. Structural changes in arm muscles after microgravity.

    PubMed

    Mayet-Sornay, M H; Hoppeler, H; Shenkman, B S; Desplanches, D

    2000-01-01

    Disuse muscle atrophy is a well-known consequence of spaceflight. However, most of the available muscle data concern lower limb muscles of rats and primates exposed to microgravity aboard Russian Cosmos biosatellites and American Space Shuttles. The purpose of our study was, therefore, to provide information concerning the effects of a 14-day spaceflight on two upper limb muscles of rhesus monkeys (Macaca mulatta). Our objective was to compare structural adaptations after 14 days of microgravity in a slow-twitch extensor muscle, i.e., the triceps, with a fast-twitch flexor muscle, i.e., the biceps. We hypothesize that muscle responses will be muscle specific, i.e., slow will differ from fast muscles, flexors will differ from extensors, and arms will differ from legs.

  20. Muscle disorders and rehabilitation in canine athletes.

    PubMed

    Steiss, Janet E

    2002-01-01

    Muscle disorders associated with physical exertion in human athletes include delayed-onset muscle soreness, muscle strain, muscle tears, rhabdomyolysis, and acute and chronic compartment syndromes. Given that the structure of muscle is similar among different species, it is reasonable to expect that dogs experience the same phenomena. This article focuses on several of the muscle disorders of bird dogs, namely, coccygeal muscle injury and infraspinatus muscle contracture, and on those of dogs involved in tracking-obedience-protection training, namely, fibrotic myopathy, with an additional discussion of muscle strain. For injury prevention, one important area that can be adapted to canine athletes is the incorporation of warm-up and cool-down into the training program.

  1. Effects of aestivation on skeletal muscle performance.

    PubMed

    James, Rob S

    2010-01-01

    Fitness, ecology, and behaviour of vertebrates are dependent upon locomotor performance. Locomotor performance can be constrained by underlying intrinsic skeletal muscle properties. Skeletal muscle is a highly plastic tissue undergoing phenotypic change in response to alteration in environment. Clinical and experimental models of muscle disuse cause decreases in skeletal muscle size and mechanical performance. However, in natural models of skeletal muscle disuse, both atrophy and changes in mechanical properties are more limited. Aestivation in frogs can cause decreases in muscle cross-sectional area and changes in some enzyme activities, with effects varying among muscles. However, long-term aestivation causes limited changes in muscle mechanics during simulated sprint or endurance type activities. Therefore, at least in frogs, there is maintenance of skeletal muscle performance during prolonged periods of aestivation, allowing avoidance of harsh environmental conditions without compromising the locomotor capacity to perform fitness-related activities when favourable environmental conditions return.

  2. Regulation of skeletal muscle perfusion during exercise

    NASA Technical Reports Server (NTRS)

    Delp, M. D.; Laughlin, M. H.

    1998-01-01

    For exercise to be sustained, it is essential that adequate blood flow be provided to skeletal muscle. The local vascular control mechanisms involved in regulating muscle perfusion during exercise include metabolic control, endothelium-mediated control, propagated responses, myogenic control, and the muscle pump. The primary determinant of muscle perfusion during sustained exercise is the metabolic rate of the muscle. Metabolites from contracting muscle diffuse to resistance arterioles and act directly to induce vasodilation, or indirectly to inhibit noradrenaline release from sympathetic nerve endings and oppose alpha-adrenoreceptor-mediated vasoconstriction. The vascular endothelium also releases vasodilator substances (e.g., prostacyclin and nitric oxide) that are prominent in establishing basal vascular tone, but these substances do not appear to contribute to the exercise hyperemia in muscle. Endothelial and smooth muscle cells may also be involved in propagating vasodilator signals along arterioles to parent and daughter vessels. Myogenic autoregulation does not appear to be involved in the exercise hyperemia in muscle, but the rhythmic propulsion of blood from skeletal muscle veins facilitates venous return to the heart and muscle perfusion. It appears that the primary determinants of sustained exercise hyperemia in skeletal muscle are metabolic vasodilation and increased vascular conductance via the muscle pump. Additionally, sympathetic neural control is important in regulating muscle blood flow during exercise.

  3. Viscoelastic properties of laryngeal posturing muscles

    NASA Astrophysics Data System (ADS)

    Alipour, Fariborz; Hunter, Eric; Titze, Ingo

    2003-10-01

    Viscoelastic properties of canine laryngeal muscles were measured in a series of in vitro experiments. Laryngeal posturing that controls vocal fold length and adduction/abduction is an essential component of the voice production. The dynamics of posturing depends on the viscoelastic and physiological properties of the laryngeal muscles. The time-dependent and nonlinear behaviors of these tissues are also crucial in the voice production and pitch control theories. The lack of information on some of these muscles such as posterior cricoarytenoid muscle (PCA), lateral cricoarytenoid muscle (LCA), and intraarytenoid muscle (IA) was the major incentive for this study. Samples of PCA and LCA muscles were made from canine larynges and mounted on a dual-servo system (Ergometer) as described in our previous works. Two sets of experiments were conducted on each muscle, a 1-Hz stretch and release experiment that provides stress-strain data and a stress relaxation test. Data from these muscles were fitted to viscoelastic models and Young's modulus and viscoelastic constants are obtained for each muscle. Preliminary data indicates that elastics properties of these muscles are similar to those of thyroarytenoid and cricothyroid muscles. The relaxation response of these muscles also shows some similarity to other laryngeal muscles in terms of time constants.

  4. Nuclear positioning in muscle development and disease

    PubMed Central

    Folker, Eric S.; Baylies, Mary K.

    2013-01-01

    Muscle disease as a group is characterized by muscle weakness, muscle loss, and impaired muscle function. Although the phenotype is the same, the underlying cellular pathologies, and the molecular causes of these pathologies, are diverse. One common feature of many muscle disorders is the mispositioning of myonuclei. In unaffected individuals, myonuclei are spaced throughout the periphery of the muscle fiber such that the distance between nuclei is maximized. However, in diseased muscles, the nuclei are often clustered within the center of the muscle cell. Although this phenotype has been acknowledged for several decades, it is often ignored as a contributor to muscle weakness. Rather, these nuclei are taken only as a sign of muscle repair. Here we review the evidence that mispositioned myonuclei are not merely a symptom of muscle disease but also a cause. Additionally, we review the working models for how myonuclei move from two different perspectives: from that of the nuclei and from that of the cytoskeleton. We further compare and contrast these mechanisms with the mechanisms of nuclear movement in other cell types both to draw general themes for nuclear movement and to identify muscle-specific considerations. Finally, we focus on factors that can be linked to muscle disease and find that genes that regulate myonuclear movement and positioning have been linked to muscular dystrophy. Although the cause-effect relationship is largely speculative, recent data indicate that the position of nuclei should no longer be considered only a means to diagnose muscle disease. PMID:24376424

  5. Structure-function relationship of skeletal muscle provides inspiration for design of new artificial muscle

    NASA Astrophysics Data System (ADS)

    Gao, Yingxin; Zhang, Chi

    2015-03-01

    A variety of actuator technologies have been developed to mimic biological skeletal muscle that generates force in a controlled manner. Force generation process of skeletal muscle involves complicated biophysical and biochemical mechanisms; therefore, it is impossible to replace biological muscle. In biological skeletal muscle tissue, the force generation of a muscle depends not only on the force generation capacity of the muscle fiber, but also on many other important factors, including muscle fiber type, motor unit recruitment, architecture, structure and morphology of skeletal muscle, all of which have significant impact on the force generation of the whole muscle or force transmission from muscle fibers to the tendon. Such factors have often been overlooked, but can be incorporated in artificial muscle design, especially with the discovery of new smart materials and the development of innovative fabrication and manufacturing technologies. A better understanding of the physiology and structure-function relationship of skeletal muscle will therefore benefit the artificial muscle design. In this paper, factors that affect muscle force generation are reviewed. Mathematical models used to model the structure-function relationship of skeletal muscle are reviewed and discussed. We hope the review will provide inspiration for the design of a new generation of artificial muscle by incorporating the structure-function relationship of skeletal muscle into the design of artificial muscle.

  6. Taurine and skeletal muscle disorders.

    PubMed

    Conte Camerino, Diana; Tricarico, Domenico; Pierno, Sabata; Desaphy, Jean-François; Liantonio, Antonella; Pusch, Michael; Burdi, Rosa; Camerino, Claudia; Fraysse, Bodvael; De Luca, Annamaria

    2004-01-01

    Taurine is abundantly present in skeletal muscle. We give evidence that this amino acid exerts both short-term and long-term actions in the control of ion channel function and calcium homeostasis in striated fibers. Short-term actions can be estimated as the ability of this amino acid to acutely modulate both ion channel gating and the function of the structures involved in calcium handling. Long-term effects can be disclosed in situations of tissue taurine depletion and are likely related to the ability of the intracellular taurine to control transducing pathways as well as homeostatic and osmotic equilibrium in the tissue. The two activities are strictly linked because the intracellular level of taurine modulates the sensitivity of skeletal muscle to the exogenous application of taurine. Myopathies in which ion channels are directly or indirectly involved, as well as inherited or acquired pathologies characterized by metabolic alterations and change in calcium homeostasis, are often correlated with change in muscle taurine concentration and consequently with an enhanced therapeutic activity of this amino acid. We discuss both in vivo and in vitro evidence that taurine, through its ability to control sarcolemmal excitability and muscle contractility, can prove beneficial effects in many muscle dysfunctions.

  7. Isokinetic evaluation of trunk muscles.

    PubMed

    Langrana, N A; Lee, C K

    1984-03-01

    The purpose of this study is to identify those individuals at risk who have weak trunk muscles and are prone to back pain. The overall thrust of this research is to develop a quantitative method to assess dynamic strength of the trunk muscles. Two unique isokinetic strength testing units in sitting and standing postures have been designed. Three groups of volunteers were tested at different times and places. Quantitative measurements of the maximum strength, fatigue behavior of the abdominal and paraspinal muscles, maximum strength in different age groups and the role of the iliopsoas muscle have been performed. The study shows that women have lower maximum strength but equal or better fatigue endurance than men. There is a significant change in maximum strength with age. The maximum abdominal strength change with age showed a bimodal distribution. The iliopsoas muscle approximately doubled the maximum back strength in flexion. The test in the sitting posture was tolerated better than the test in the standing posture. Isokinetic back strength testing in the sitting posture was found to be effective and safe.

  8. Laser therapy of muscle injuries.

    PubMed

    Dawood, Munqith S; Al-Salihi, Anam Rasheed; Qasim, Amenah Wala'a

    2013-05-01

    Low-level lasers are used in general therapy and healing process due to their good photo-bio-stimulation effects. In this paper, the effects of diode laser and Nd:YAG laser on the healing process of practically managed skeletal muscle trauma has been successfully studied. Standard impact trauma was induced by using a specially designed mechanical device. The impacted muscle was left for 3 days for complete development of blunt trauma. After that it was irradiated by five laser sessions for 5 days. Two types of lasers were used; 785-nm diode laser and 1.064-nm Nd:YAG laser, both in continuous and pulsed modes. A special electronic circuit was designed and implemented to modulate the diode laser for this purpose. Tissue samples of crushed skeletal muscle have been dissected from the injured irradiated muscle then bio-chemically analyzed for the regeneration of contractile and collagenous proteins using Lowry assay for protein determination and Reddy and Enwemeka assay for hydroxyproline determination. The results showed that both lasers stimulate the regeneration capability of traumatized skeletal muscle. The diode laser in CW and pulsed modes showed better results than the Nd:YAG in accelerating the preservation of the normal tissue content of collagenous and contractile proteins beside controlling the regeneration of non-functional fibrous tissue. This study proved that the healing achieved by the laser treatment was faster than the control group by 15-20 days.

  9. Therapeutic effects of massage and electrotherapy on muscle tone, stiffness and muscle contraction following gastrocnemius muscle fatigue

    PubMed Central

    Wang, Joong-San

    2017-01-01

    [Purpose] This study aimed to examine the effects of a combined intervention consisting of massage therapy and transcutaneous electrical nerve stimulation on gastrocnemius muscle fatigue, assessing whether the intervention improved muscle tone, stiffness, and muscle contraction. [Subjects and Methods] The subjects were 20 healthy males in their 20s who were equally divided into a transcutaneous electrical nerve stimulation group and a combined therapy group that received a combination of massage therapy and transcutaneous electrical nerve stimulation. Muscle fatigue was triggered on the gastrocnemius muscle, and the effects of intervention method on muscle tone, stiffness, and muscle contraction were examined over time. [Results] Lateral and medial gastrocnemius muscle tone and stiffness significantly increased and gastrocnemius muscle contraction significantly decreased in each group immediately after fatigue was triggered on the gastrocnemius muscle. There was no difference in the effects of the two intervention methods over time. [Conclusion] This study verified that a combined therapy of massage therapy and transcutaneous electrical nerve stimulation was able to be used effectively in improving muscle tone, stiffness, muscle contraction, thereby reducing gastrocnemius muscle fatigue. PMID:28210061

  10. Partial muscle carnitine palmitoyltransferase-A deficiency

    SciTech Connect

    Ross, N.S.; Hoppel, C.L.

    1987-01-02

    After initiation of ibuprofen therapy, a 45-year-old woman developed muscle weakness and tenderness with rhabdomyolysis, culminating in respiratory failure. A muscle biopsy specimen showed a vacuolar myopathy, and markedly decreased muscle carnitine content and carnitine palmitoyltransferase activity. Following recovery, muscle carnitine content was normal but carnitine palmitoyltransferase activity was still abnormally low. The ratio of palmitoyl-coenzyme A plus carnitine to palmitoylcarnitine oxidation by muscle mitochondria isolated from the patient was markedly decreased. The authors conclude that transiently decreased muscle carnitine content interacted with partial deficiency of carnitine palmitoyltransferase-A to produce rhabdomyolysis and respiratory failure and that ibuprofen may have precipitated the clinical event.

  11. Pelvic floor muscle rehabilitation using biofeedback.

    PubMed

    Newman, Diane K

    2014-01-01

    Pelvic floor muscle exercises have been recommended for urinary incontinence since first described by obstetrician gynecologist Dr. Arnold Kegel more than six decades ago. These exercises are performed to strengthen pelvic floor muscles, provide urethral support to prevent urine leakage, and suppress urgency. In clinical urology practice, expert clinicians also teach patients how to relax the muscle to improve bladder emptying and relieve pelvic pain caused by muscle spasm. When treating lower urinary tract symptoms, an exercise training program combined with biofeedback therapy has been recommended as first-line treatment. This article provides clinical application of pelvic floor muscle rehabilitation using biofeedback as a technique to enhance pelvic floor muscle training.

  12. Torsional carbon nanotube artificial muscles.

    PubMed

    Foroughi, Javad; Spinks, Geoffrey M; Wallace, Gordon G; Oh, Jiyoung; Kozlov, Mikhail E; Fang, Shaoli; Mirfakhrai, Tissaphern; Madden, John D W; Shin, Min Kyoon; Kim, Seon Jeong; Baughman, Ray H

    2011-10-28

    Rotary motors of conventional design can be rather complex and are therefore difficult to miniaturize; previous carbon nanotube artificial muscles provide contraction and bending, but not rotation. We show that an electrolyte-filled twist-spun carbon nanotube yarn, much thinner than a human hair, functions as a torsional artificial muscle in a simple three-electrode electrochemical system, providing a reversible 15,000° rotation and 590 revolutions per minute. A hydrostatic actuation mechanism, as seen in muscular hydrostats in nature, explains the simultaneous occurrence of lengthwise contraction and torsional rotation during the yarn volume increase caused by electrochemical double-layer charge injection. The use of a torsional yarn muscle as a mixer for a fluidic chip is demonstrated.

  13. Torsional Carbon Nanotube Artificial Muscles

    NASA Astrophysics Data System (ADS)

    Foroughi, Javad; Spinks, Geoffrey M.; Wallace, Gordon G.; Oh, Jiyoung; Kozlov, Mikhail E.; Fang, Shaoli; Mirfakhrai, Tissaphern; Madden, John D. W.; Shin, Min Kyoon; Kim, Seon Jeong; Baughman, Ray H.

    2011-10-01

    Rotary motors of conventional design can be rather complex and are therefore difficult to miniaturize; previous carbon nanotube artificial muscles provide contraction and bending, but not rotation. We show that an electrolyte-filled twist-spun carbon nanotube yarn, much thinner than a human hair, functions as a torsional artificial muscle in a simple three-electrode electrochemical system, providing a reversible 15,000° rotation and 590 revolutions per minute. A hydrostatic actuation mechanism, as seen in muscular hydrostats in nature, explains the simultaneous occurrence of lengthwise contraction and torsional rotation during the yarn volume increase caused by electrochemical double-layer charge injection. The use of a torsional yarn muscle as a mixer for a fluidic chip is demonstrated.

  14. Relationship of Skeletal Muscle Development and Growth to Breast Muscle Myopathies: A Review.

    PubMed

    Velleman, Sandra G

    2015-12-01

    Selection in meat-type birds has focused on growth rate, muscling, and feed conversion. These strategies have made substantial improvements but have affected muscle structure, repair mechanisms, and meat quality, especially in the breast muscle. The increase in muscle fiber diameters has reduced available connective tissue spacing, reduced blood supply, and altered muscle metabolism in the breast muscle. These changes have increased muscle fiber degeneration and necrosis but have limited muscle repair mechanisms mediated by the adult myoblast (satellite cell) population of cells, likely resulting in the onset of myopathies. This review focuses on muscle growth mechanisms and how changes in the cellular development of the breast muscle may be associated with breast muscle myopathies occurring in meat-type birds.

  15. Repositioning forelimb superficialis muscles: tendon attachment and muscle activity enable active relocation of functional myofibers.

    PubMed

    Huang, Alice H; Riordan, Timothy J; Wang, Lingyan; Eyal, Shai; Zelzer, Elazar; Brigande, John V; Schweitzer, Ronen

    2013-09-16

    The muscles that govern hand motion are composed of extrinsic muscles that reside within the forearm and intrinsic muscles that reside within the hand. We find that the extrinsic muscles of the flexor digitorum superficialis (FDS) first differentiate as intrinsic muscles within the hand and then relocate as myofibers to their final position in the arm. This remarkable translocation of differentiated myofibers across a joint is dependent on muscle contraction and muscle-tendon attachment. Interestingly, the intrinsic flexor digitorum brevis (FDB) muscles of the foot are identical to the FDS in tendon pattern and delayed developmental timing but undergo limited muscle translocation, providing strong support for evolutionary homology between the FDS and FDB muscles. We propose that the intrinsic FDB pattern represents the original tetrapod limb and that translocation of the muscles to form the FDS is a mammalian evolutionary addition.

  16. Calcium regulation of muscle contraction.

    PubMed Central

    Szent-Györgyi, A G

    1975-01-01

    Calcium triggers contraction by reaction with regulatory proteins that in the absence of calcium prevent interaction of actin and myosin. Two different regulatory systems are found in different muscles. In actin-linked regulation troponin and tropomyosin regulate actin by blocking sites on actin required for complex formation with myosin; in myosin-linked regulation sites on myosin are blocked in the absence of calcium. The major features of actin control are as follows: there is a requirement for tropomyosin and for a troponin complex having three different subunits with different functions; the actin displays a cooperative behavior; and a movement of tropomyosin occurs controlled by the calcium binding on troponin. Myosin regulation is controlled by a regulatory subunit that can be dissociated in scallop myosin reversibly by removing divalent cations with EDTA. Myosin control can function with pure actin in the absence of tropomyosin. Calcium binding and regulation of molluscan myosins depend on the presence of regulatory light chains. It is proposed that the light chains function by sterically blocking myosin sites in the absence of calcium, and that the "off" state of myosin requires cooperation between the two myosin heads. Both myosin control and actin control are widely distributed in different organisms. Many invertebrates have muscles with both types of regulation. Actin control is absent in the muscles of molluscs and in several minor phyla that lack troponin. Myosin control is not found in striated vertebrate muscles and in the fast muscles of crustacean decapods, although regulatory light chains are present. While in vivo myosin control may not be excluded from vertebrate striated muscles, myosin control may be absent as a result of mutations of the myosin heavy chain. PMID:806311

  17. Characteristics of locomotion, muscle strength, and muscle tissue in regenerating rat skeletal muscles.

    PubMed

    Iwata, Akira; Fuchioka, Satoshi; Hiraoka, Koichi; Masuhara, Mitsuhiko; Kami, Katsuya

    2010-05-01

    Although numerous studies have aimed to elucidate the mechanisms used to repair the structure and function of injured skeletal muscles, it remains unclear how and when movement recovers following damage. We performed a temporal analysis to characterize the changes in movement, muscle function, and muscle structure after muscle injury induced by the drop-mass technique. At each time-point, movement recovery was determined by ankle kinematic analysis of locomotion, and functional recovery was represented by isometric force. As a histological analysis, the cross-sectional area of myotubes was measured to examine structural regeneration. The dorsiflexion angle of the ankle, as assessed by kinematic analysis of locomotion, increased after injury and then returned to control levels by day 14 post-injury. The isometric force returned to normal levels by day 21 post-injury. However, the size of the myotubes did not reach normal levels, even at day 21 post-injury. These results indicate that recovery of locomotion occurs prior to recovery of isometric force and that functional recovery occurs earlier than structural regeneration. Thus, it is suggested that recovery of the movement and function of injured skeletal muscles might be insufficient as markers for estimating the degree of neuromuscular system reconstitution.

  18. Muscle cramps in liver disease.

    PubMed

    Mehta, Shivang S; Fallon, Michael B

    2013-11-01

    Muscle cramps are common in patients with liver disease and adversely influence quality of life. The exact mechanisms by which they occur remain unclear, although a number of pathophysiological events unique to liver disease may contribute. Clinical studies have identified alterations in 3 areas: nerve function, energy metabolism, and plasma volume/electrolytes. Treatments have focused on these particular areas with varied results. This review will focus on the clinical features of muscle cramps in patients with liver disease and review potential mechanisms and current therapies.

  19. Muscle Paralysis in Herpes Zoster

    PubMed Central

    Rubin, David; Fusfeld, Robert D.

    1965-01-01

    Herpes zoster may, in some instances, cause motor paralysis as well as the usual sensory and cutaneous manifestations. It is suggested that the presence of electromyographic denervation potentials be used as the criterion of muscle paresis in order to avoid mistaking atrophy of disuse for true lower motor neuron disease. Use of the proper physical therapy procedures hastens the recovery of function and may serve to retard denervation atrophy and fibrosis in patients with muscle paralysis. ImagesFigure 1 (Case 1).Figure 1 (Case 1). PMID:5828175

  20. Exercise, muscle, and CHO metabolism.

    PubMed

    Hargreaves, M

    2015-12-01

    Carbohydrates (CHO) are a key source of energy for contracting skeletal muscle during strenuous exercise and fatigue during such exercise often coincides with CHO depletion. Our current understanding of the importance of CHO for exercise metabolism has its foundations in classic studies in the early 20th century by Scandinavian physiologists and Bengt Saltin contributed significantly to that tradition. This brief review summarizes our contemporary understanding of key aspects of muscle glycogen and glucose metabolism during exercise, through the lens of seminal studies by Bengt Saltin.

  1. Spontaneous waves in muscle fibres

    NASA Astrophysics Data System (ADS)

    Günther, Stefan; Kruse, Karsten

    2007-11-01

    Mechanical oscillations are important for many cellular processes, e.g. the beating of cilia and flagella or the sensation of sound by hair cells. These dynamic states originate from spontaneous oscillations of molecular motors. A particularly clear example of such oscillations has been observed in muscle fibers under non-physiological conditions. In that case, motor oscillations lead to contraction waves along the fiber. By a macroscopic analysis of muscle fiber dynamics we find that the spontaneous waves involve non-hydrodynamic modes. A simple microscopic model of sarcomere dynamics highlights mechanical aspects of the motor dynamics and fits with the experimental observations.

  2. Muscle assembly: a titanic achievement?

    PubMed

    Gregorio, C C; Granzier, H; Sorimachi, H; Labeit, S

    1999-02-01

    The formation of perfectly aligned myofibrils in striated muscle represents a dramatic example of supramolecular assembly in eukaryotic cells. Recently, considerable progress has been made in deciphering the roles that titin, the third most abundant protein in muscle, has in this process. An increasing number of sarcomeric proteins (ligands) are being identified that bind to specific titin domains. Titin may serve as a molecular blueprint for sarcomere assembly and turnover by specifying the precise position of its ligands within each half-sarcomere in addition to functioning as a molecular spring that maintains the structural integrity of the contracting myofibrils.

  3. Changes in muscle spindle firing in response to length changes of neighboring muscles.

    PubMed

    Smilde, Hiltsje A; Vincent, Jake A; Baan, Guus C; Nardelli, Paul; Lodder, Johannes C; Mansvelder, Huibert D; Cope, Tim C; Maas, Huub

    2016-06-01

    Skeletal muscle force can be transmitted to the skeleton, not only via its tendons of origin and insertion but also through connective tissues linking the muscle belly to surrounding structures. Through such epimuscular myofascial connections, length changes of a muscle may cause length changes within an adjacent muscle and hence, affect muscle spindles. The aim of the present study was to investigate the effects of epimuscular myofascial forces on feedback from muscle spindles in triceps surae muscles of the rat. We hypothesized that within an intact muscle compartment, muscle spindles not only signal length changes of the muscle in which they are located but can also sense length changes that occur as a result of changing the length of synergistic muscles. Action potentials from single afferents were measured intra-axonally in response to ramp-hold release (RHR) stretches of an agonistic muscle at different lengths of its synergist, as well as in response to synergist RHRs. A decrease in force threshold was found for both soleus (SO) and lateral gastrocnemius afferents, along with an increase in length threshold for SO afferents. In addition, muscle spindle firing could be evoked by RHRs of the synergistic muscle. We conclude that muscle spindles not only signal length changes of the muscle in which they are located but also local length changes that occur as a result of changing the length and relative position of synergistic muscles.

  4. Muscle force recovery in relation to muscle oxygenation.

    PubMed

    Ufland, Pierre; Lapole, Thomas; Ahmaidi, Said; Buchheit, Martin

    2012-09-01

    The aim of this study was to investigate the relative contribution of human muscle reoxygenation on force recovery following a maximal voluntary contraction (MVC). Ten athletes (22·9 ± 4·0 years) executed a plantar-flexion sequence including two repeated MVCs [i.e. a 30-s MVC (MVC(30)) followed by a 10-s MVC (MVC(10))] separated by 10, 30, 60, 120 or 300 s of passive recovery. A 10-min passive recovery period was allowed between each MVC sequence. This procedure was randomly repeated with two different recovery conditions: without (CON) or with (OCC) arterial occlusion of the medial gastrocnemius. During OCC, the occlusion was maintained from the end of MVC(30) to the end of MVC(10). Muscle oxygenation (Near-infrared spectroscopy, NIRS, [Hb(diff) ]) was continuously measured during all MVC sequences and expressed as a percentage of the maximal changes in optical density observed during MVC(30). Maximal Torque was analysed at the start of each contraction. Torque during each MVC(10) was expressed as a percentage of the Torque during the previous MVC(30). Torque recovery was complete within 300 s after MVC(30) during CON (MVC(10) = 101·8 ± 5·0%); 88·6 ± 8·9% of the Torque was recovered during OCC (P = 0·005). There was also a moderate correlation between absolute level of muscle oxygenation and Torque (r = 0·32 (90% CI, 0·09;0·52), P = 0·02). Present findings confirm the role of human muscle oxygenation in muscular force recovery during repeated-maximal efforts. However, the correlation between absolute muscle oxygenation and force level during recovery is only moderate, suggesting that other mechanisms are likely involved in the force recovery process.

  5. Force summation between muscles: are muscles independent actuators?

    PubMed

    Sandercock, Thomas G; Maas, Huub

    2009-01-01

    Muscle force can be transmitted via connective tissues to neighboring muscles. The goal of this research is to determine the extent to which this effects force summation between synergists during physiological conditions. This manuscript reviews two studies examining the interaction between synergists in cat hindlimb. Deeply anesthetized cats were mounted in a rigid frame with the foot secured to a six-degree-of-freedom load cell coupled to a robotic arm. Muscles were stimulated by implanted nerve cuff electrodes. In the first study, force summation was measured during isometric contractions. Interactions were studied between the lateral gastrocnemius (LG)/soleus (SOL) and the medial gastrocnemius (MG) as well as between rectus femoris and vastus lateralis. Invariably, nonlinear force summation was less than 10% of maximum force for all three translational directions and all three rotational directions. The second study investigated if force transmission from SOL fibers was affected by length changes of its two-joint synergists. Ankle plantar flexor moment, upon activation of only SOL, was measured for various knee angles (70 degrees -140 degrees ), which involved substantial length changes of LG, MG, and plantaris muscles. Ankle angle was kept constant (80 degrees -90 degrees ). SOL ankle moment was not significantly (P = 0.11) affected by changes in knee angle, neither were the half-relaxation time and the maximal rate of relaxation. The connective tissue links between SOL and LG were further studied during a tenotomy of the SOL and demonstrated that the connective links can transmit approximately 50% of the force from the SOL to the LG in nonphysiological conditions. In conclusion, despite strong connective tissue linkages, in cat hindlimb synergistic muscles appear to be independent actuators if acting in physiological conditions.

  6. Amino Acid Sensing in Skeletal Muscle.

    PubMed

    Moro, Tatiana; Ebert, Scott M; Adams, Christopher M; Rasmussen, Blake B

    2016-11-01

    Aging impairs skeletal muscle protein synthesis, leading to muscle weakness and atrophy. However, the underlying molecular mechanisms remain poorly understood. Here, we review evidence that mammalian/mechanistic target of rapamycin complex 1 (mTORC1)-mediated and activating transcription factor 4 (ATF4)-mediated amino acid (AA) sensing pathways, triggered by impaired AA delivery to aged skeletal muscle, may play important roles in skeletal muscle aging. Interventions that alleviate age-related impairments in muscle protein synthesis, strength, and/or muscle mass appear to do so by reversing age-related changes in skeletal muscle AA delivery, mTORC1 activity, and/or ATF4 activity. An improved understanding of the mechanisms and roles of AA sensing pathways in skeletal muscle may lead to evidence-based strategies to attenuate sarcopenia.

  7. Pilates: Build Strength in Your Core Muscles

    MedlinePlus

    ... intimidating, but it's an accessible way to build strength in your core muscles for better posture, balance ... fanatics. It's actually an accessible way to build strength in your core muscles for better posture, balance ...

  8. Exercise-Induced Skeletal Muscle Damage.

    ERIC Educational Resources Information Center

    Evans, William J.

    1987-01-01

    Eccentric exercise, in which the muscles exert force by lengthening, is associated with delayed onset muscle soreness. How soreness occurs, how recovery proceeds, and what precautions athletes should take are described. (Author/MT)

  9. Structural alterations of skeletal muscle in copd

    PubMed Central

    Mathur, Sunita; Brooks, Dina; Carvalho, Celso R. F.

    2014-01-01

    Background: Chronic obstructive pulmonary disease (COPD) is a respiratory disease associated with a systemic inflammatory response. Peripheral muscle dysfunction has been well characterized in individuals with COPD and results from a complex interaction between systemic and local factors. Objective: In this narrative review, we will describe muscle wasting in people with COPD, the associated structural changes, muscle regenerative capacity and possible mechanisms for muscle wasting. We will also discuss how structural changes relate to impaired muscle function and mobility in people with COPD. Key Observations: Approximately 30–40% of individuals with COPD experience muscle mass depletion. Furthermore, muscle atrophy is a predictor of physical function and mortality in this population. Associated structural changes include a decreased proportion and size of type-I fibers, reduced oxidative capacity and mitochondrial density mainly in the quadriceps. Observations related to impaired muscle regenerative capacity in individuals with COPD include a lower proportion of central nuclei in the presence or absence of muscle atrophy and decreased maximal telomere length, which has been correlated with reduced muscle cross-sectional area. Potential mechanisms for muscle wasting in COPD may include excessive production of reactive oxygen species (ROS), altered amino acid metabolism and lower expression of peroxisome proliferator-activated receptors-gamma-coactivator 1-alpha mRNA. Despite a moderate relationship between muscle atrophy and function, impairments in oxidative metabolism only seems weakly related to muscle function. Conclusion: This review article demonstrates the cellular modifications in the peripheral muscle of people with COPD and describes the evidence of its relationship to muscle function. Future research will focus on rehabilitation strategies to improve muscle wasting and maximize function. PMID:24678302

  10. [How I investigate...respiratory muscle disorders].

    PubMed

    Lehance, C; Close, P; Bury, Th

    2004-01-01

    As for other skeletal muscles, ventilatory muscle performance can be described in terms of strength and endurance. Ventilatory muscle strength is measured, for example, as the maximum inspiratory and expiratory mouth pressures. It is now a routine procedure in many pulmonary function laboratories. Measurements of ventilatory muscle endurance are more difficult but two general types of tests are used: maximum voluntary ventilation and inspiratory threshold loading.

  11. Intrafusal muscle fibre types in frog spindles.

    PubMed

    Diwan, F H; Ito, F

    1989-04-01

    Muscle spindles from bullfrog semitendinosus, iliofibularis and sartorius muscles were examined with light and electron microscopy. Four types of intrafusal muscle fibre were identified according to their diameter, central nucleation and reticular zone arrangement: a large nuclear bag fibre, a medium nuclear bag fibre, and two types of small nuclear chain fibres with and without a reticular zone, respectively. It is suggested that they are comparable to the nuclear bag1, bag2 and chain fibres in mammalian muscle spindles.

  12. Muscle Cramp - A Common Pain

    MedlinePlus

    ... within minutes and typically do not warrant medical attention. “You can usually treat muscle cramps with self-care measures,” says Dr. Quist. Here are a few of the methods: Stop doing whatever activity triggered the cramp. Gently ...

  13. Vitamin D and Muscle Function.

    PubMed

    Dawson-Hughes, Bess

    2017-03-21

    Muscle weakness is a hallmark of severe vitamin D deficiency, but the effect of milder vitamin D deficiency or insufficiency on muscle mass and performance and risk of falling is uncertain. In this presentation, I review the evidence that vitamin D influences muscle mass and performance, balance, and risk of falling in older adults. Special consideration is given to the impact of both the starting 25-hydroxyvitamin D [25(OH)D] level and the dose administered on the clinical response to supplemental vitamin D in older men and women. Based on available evidence, older adults with serum 25(OH)D levels <40nmol/L appear most likely to improve their muscle performance with supplementation. The vitamin D dose range of 800-1000 IU per day has been effective in many studies; lower doses have generally been ineffective and several doses above this range have increased the risk of falls. In conclusion, older adults with serum 25(OH)D levels <40nmol/L are likely to have fewer falls if supplemented with 800 to 1,000 IU per day of vitamin D.

  14. Human jaw and muscle modelling.

    PubMed

    Peck, Christopher C; Hannam, Alan G

    2007-04-01

    Dynamic mathematical modelling is an invaluable method to help understand the biomechanics of the anatomically and functionally complex masticatory system. It provides insight into variables which are impossible to measure directly such as joint loads and individual muscle tensions, and into physical relationships between jaw structure and function. Individual parameters can be modified easily to understand their influence on function. Our models are constructed with best available structural and functional data, and evaluated against human jaw behaviour. Image data provide hard and soft tissue morphology and the jaw's inertial properties. The drive to the system is provided by actuators which simulate active and passive jaw muscle properties. In whole-jaw modelling, muscle models which behave plausibly rather than mimic the ultra-structural cross-bridge interactions are common since they are computationally feasible. Whole-jaw models have recently incorporated flexible finite-elements to explore tissue distortion in the temporomandibular joint and tongue movements. Furthermore, the jaw has been integrated with laryngeal models to explore complex tasks such as swallowing. These dynamic models have helped better understand joint loading, movement constraints and muscle activation strategies. Future directions will include further incorporation of rigid and flexible model dynamics and the creation of subject-specific models to better understand the functional implications of pathology.

  15. Multidirectional Artificial Muscles from Nylon.

    PubMed

    Mirvakili, Seyed M; Hunter, Ian W

    2017-01-01

    Multidirectional artificial muscles are made from highly oriented nylon filaments. Thanks to the low thermal conductivity of nylon and its anisotropic thermal expansion, bending occurs when a nylon beam is differentially heated. This heat can be generated via a Joule heating mechanism or high power laser pulses.

  16. Novel Analog For Muscle Deconditioning

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, Lori; Ryder, Jeff; Buxton, Roxanne; Redd, Elizabeth; Scott-Pandorf, Melissa; Hackney, Kyle; Fiedler, James; Bloomberg, Jacob

    2010-01-01

    Existing models of muscle deconditioning are cumbersome and expensive (ex: bedrest). We propose a new model utilizing a weighted suit to manipulate strength, power or endurance (function) relative to body weight (BW). Methods: 20 subjects performed 7 occupational astronaut tasks while wearing a suit weighted with 0-120% of BW. Models of the full relationship between muscle function/BW and task completion time were developed using fractional polynomial regression and verified by the addition of pre- and post-flight astronaut performance data using the same tasks. Spline regression was used to identify muscle function thresholds below which task performance was impaired. Results: Thresholds of performance decline were identified for each task. Seated egress & walk (most difficult task) showed thresholds of: leg press (LP) isometric peak force/BW of 18 N/kg, LP power/BW of 18 W/kg, LP work/ BW of 79 J/kg, knee extension (KE) isokinetic/BW of 6 Nm/Kg and KE torque/BW of 1.9 Nm/kg. Conclusions: Laboratory manipulation of strength / BW has promise as an appropriate analog for spaceflight-induced loss of muscle function for predicting occupational task performance and establishing operationally relevant exercise targets.

  17. Novel Analog For Muscle Deconditioning

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, Lori; Ryder, Jeff; Buxton, Roxanne; Redd. Elizabeth; Scott-Pandorf, Melissa; Hackney, Kyle; Fiedler, James; Ploutz-Snyder, Robert; Bloomberg, Jacob

    2011-01-01

    Existing models (such as bed rest) of muscle deconditioning are cumbersome and expensive. We propose a new model utilizing a weighted suit to manipulate strength, power, or endurance (function) relative to body weight (BW). Methods: 20 subjects performed 7 occupational astronaut tasks while wearing a suit weighted with 0-120% of BW. Models of the full relationship between muscle function/BW and task completion time were developed using fractional polynomial regression and verified by the addition of pre-and postflightastronaut performance data for the same tasks. Splineregression was used to identify muscle function thresholds below which task performance was impaired. Results: Thresholds of performance decline were identified for each task. Seated egress & walk (most difficult task) showed thresholds of leg press (LP) isometric peak force/BW of 18 N/kg, LP power/BW of 18 W/kg, LP work/BW of 79 J/kg, isokineticknee extension (KE)/BW of 6 Nm/kg, and KE torque/BW of 1.9 Nm/kg.Conclusions: Laboratory manipulation of relative strength has promise as an appropriate analog for spaceflight-induced loss of muscle function, for predicting occupational task performance and establishing operationally relevant strength thresholds.

  18. Metabolic Adaptation to Muscle Ischemia

    NASA Technical Reports Server (NTRS)

    Cabrera, Marco E.; Coon, Jennifer E.; Kalhan, Satish C.; Radhakrishnan, Krishnan; Saidel, Gerald M.; Stanley, William C.

    2000-01-01

    Although all tissues in the body can adapt to varying physiological/pathological conditions, muscle is the most adaptable. To understand the significance of cellular events and their role in controlling metabolic adaptations in complex physiological systems, it is necessary to link cellular and system levels by means of mechanistic computational models. The main objective of this work is to improve understanding of the regulation of energy metabolism during skeletal/cardiac muscle ischemia by combining in vivo experiments and quantitative models of metabolism. Our main focus is to investigate factors affecting lactate metabolism (e.g., NADH/NAD) and the inter-regulation between carbohydrate and fatty acid metabolism during a reduction in regional blood flow. A mechanistic mathematical model of energy metabolism has been developed to link cellular metabolic processes and their control mechanisms to tissue (skeletal muscle) and organ (heart) physiological responses. We applied this model to simulate the relationship between tissue oxygenation, redox state, and lactate metabolism in skeletal muscle. The model was validated using human data from published occlusion studies. Currently, we are investigating the difference in the responses to sudden vs. gradual onset ischemia in swine by combining in vivo experimental studies with computational models of myocardial energy metabolism during normal and ischemic conditions.

  19. Integrated expression analysis of muscle hypertrophy identifies Asb2 as a negative regulator of muscle mass

    PubMed Central

    Davey, Jonathan R.; Watt, Kevin I.; Parker, Benjamin L.; Chaudhuri, Rima; Ryall, James G.; Cunningham, Louise; Qian, Hongwei; Sartorelli, Vittorio; Chamberlain, Jeffrey; James, David E.

    2016-01-01

    The transforming growth factor-β (TGF-β) signaling network is a critical regulator of skeletal muscle mass and function and, thus, is an attractive therapeutic target for combating muscle disease, but the underlying mechanisms of action remain undetermined. We report that follistatin-based interventions (which modulate TGF-β network activity) can promote muscle hypertrophy that ameliorates aging-associated muscle wasting. However, the muscles of old sarcopenic mice demonstrate reduced response to follistatin compared with healthy young-adult musculature. Quantitative proteomic and transcriptomic analyses of young-adult muscles identified a transcription/translation signature elicited by follistatin exposure, which included repression of ankyrin repeat and SOCS box protein 2 (Asb2). Increasing expression of ASB2 reduced muscle mass, thereby demonstrating that Asb2 is a TGF-β network–responsive negative regulator of muscle mass. In contrast to young-adult muscles, sarcopenic muscles do not exhibit reduced ASB2 abundance with follistatin exposure. Moreover, preventing repression of ASB2 in young-adult muscles diminished follistatin-induced muscle hypertrophy. These findings provide insight into the program of transcription and translation events governing follistatin-mediated adaptation of skeletal muscle attributes and identify Asb2 as a regulator of muscle mass implicated in the potential mechanistic dysfunction between follistatin-mediated muscle growth in young and old muscles. PMID:27182554

  20. Effect of altering starting length and activation timing of muscle on fiber strain and muscle damage.

    PubMed

    Butterfield, Timothy A; Herzog, Walter

    2006-05-01

    Muscle strain injuries are some of the most frequent injuries in sports and command a great deal of attention in an effort to understand their etiology. These injuries may be the culmination of a series of subcellular events accumulated through repetitive lengthening (eccentric) contractions during exercise, and they may be influenced by a variety of variables including fiber strain magnitude, peak joint torque, and starting muscle length. To assess the influence of these variables on muscle injury magnitude in vivo, we measured fiber dynamics and joint torque production during repeated stretch-shortening cycles in the rabbit tibialis anterior muscle, at short and long muscle lengths, while varying the timing of activation before muscle stretch. We found that a muscle subjected to repeated stretch-shortening cycles of constant muscle-tendon unit excursion exhibits significantly different joint torque and fiber strains when the timing of activation or starting muscle length is changed. In particular, measures of fiber strain and muscle injury were significantly increased by altering activation timing and increasing the starting length of the muscle. However, we observed differential effects on peak joint torque during the cyclic stretch-shortening exercise, as increasing the starting length of the muscle did not increase torque production. We conclude that altering activation timing and muscle length before stretch may influence muscle injury by significantly increasing fiber strain magnitude and that fiber dynamics is a more important variable than muscle-tendon unit dynamics and torque production in influencing the magnitude of muscle injury.

  1. Skeletal muscle weakness in osteogeneis imperfecta mice

    PubMed Central

    Gentry, Bettina A; Ferreira, J. Andries; McCambridge, Amanda J.; Brown, Marybeth; Phillips, Charlotte L.

    2010-01-01

    Exercise intolerance, muscle fatigue and weakness are often-reported, little-investigated concerns of patients with osteogenesis imperfecta (OI). OI is a heritable connective tissue disorder hallmarked by bone fragility resulting primarily from dominant mutations in the proα1(I) or proα2(I) collagen genes and the recently discovered recessive mutations in post-translational modifying proteins of type I collagen. In this study we examined the soleus (S), plantaris (P), gastrocnemius (G), tibialis anterior (TA) and quadriceps (Q) muscles of mice expressing mild (+/oim) and moderately severe (oim/oim) OI for evidence of inherent muscle pathology. In particular, muscle weight, fiber cross-sectional area (CSA), fiber type, fiber histomorphology, fibrillar collagen content, absolute, relative and specific peak tetanic force (Po, Po/mg and Po/CSA respectively) of individual muscles were evaluated. Oim/oim mouse muscles were generally smaller, contained less fibrillar collagen, had decreased Po and an inability to sustain Po for the 300 ms testing duration for specific muscles; +/oim mice had a similar but milder skeletal muscle phenotype. +/oim mice had mild weakness of specific muscles but were less affected than their oim/oim counterparts which demonstrated readily apparent skeletal muscle pathology. Therefore muscle weakness in oim mice reflects inherent skeletal muscle pathology. PMID:20619344

  2. Breast muscle tissue characteristics in growing broilers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Muscle cell development in broilers influences growth rate, breast meat yield, and meat quality. The objective of this study was to characterize muscle tissue changes in breast muscles from two commercial lines of broilers from 21 to 56 days of age. The experiment was designed as a 2×2×6 factorial...

  3. [Tensiomyography as method of evaluating muscles status].

    PubMed

    Markulincić, Branko; Muraja, Sonja

    2007-01-01

    Sports results, as well as results of rehabilitation treatments are closely related to a detailed, strictly individualized programme of sports and rehabilitation training. It is vitally important to monitor and evaluate results constantly. Along with already standardized methods of evaluating neuromuscular system, such as electrodinamometry and isokinetic dinamometry on Cybex; tensiomyography (TMG) as method of assessing muscles status has been introduced. TMG is non-invasive, selective, objective method designed to measure time of activation, delay time as well as contraction time, relaxation time and intesity of muscle contraction in conditions of submaximum electrostimulation. The method is based on measuring the muscle belly enlargements by a superficialy placed precise electromagnetic sensor.TMG enables the examination of some otherwise inaccessible muscles like gluteus maximus muscle and also selective evaluation of single muscle head (for example m. vastus medialis, m. vastus lateralis and m. rectus femoris of m. quadriceps). Estimation of harmonisation between agonistic and antagonistic muscles, synergistic muscles and same muscles on left and right side of the body, is based on muscles biomechanical properties i.e. parameters, calculated from TMG response. Total harmonization (100%) is hardly ever the case, the lowest level sufficient muscle groups functionality is defined by 80% for lateral and 65% for agonistic/synergistic harmonisation. Harmonization below this level either reflects past injures, muscle adaptation or indicates increased exposure to injury.

  4. Distribution of veterinary drug residues among muscles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The U.S. Food and Drug Administration sets tolerances for veterinary drug residues in muscle, but does not specify which muscle should be sampled for analysis. The goal of this research was to determine if antibiotic residue levels are dependent on muscle type. In this study, penicillin G (Pen G) d...

  5. Intramuscular variation in fresh ham muscle color

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This experiment was conducted to characterize a defect involving pale muscle tissue in the superficial, ventral portion of ham muscles, resulting in two-toned appearance of cured ham products. Biceps femoris muscles (n = 200), representing 3 production systems, were obtained from the ham-boning lin...

  6. Regulation of muscle growth in neonates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review reports recent findings on the multiple factors that regulate skeletal muscle growth in neonates. Skeletal muscle is the fastest growing protein mass in neonates. The high rate of neonatal muscle growth is due to accelerated rates of protein synthesis accompanied by the rapid accumulatio...

  7. Primary psoas muscle abscess in pregnancy.

    PubMed

    Swanson, Amy; Lau, Kenneth K; Korman, Tony M; Kornman, Tony; Wallace, Euan M; Polyakov, Alex

    2008-12-01

    Primary iliacus-psoas muscle abscess formation is very uncommon during pregnancy. We present a case of a primary iliacus-psoas muscle abscess in pregnancy causing back pain with delayed diagnosis and treatment. Understanding the clinical presentation of iliacus-psoas muscle abscess helps with considering it in the differential diagnosis of back pain during pregnancy.

  8. Redox Control of Skeletal Muscle Regeneration.

    PubMed

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

    2017-02-06

    Skeletal muscle shows high plasticity in response to external demand. Moreover, adult skeletal muscle is capable of complete regeneration after injury, due to the properties of muscle stem cells (MuSCs), the satellite cells, which follow a tightly regulated myogenic program to generate both new myofibers and new MuSCs for further needs. Although reactive oxygen species (ROS) and reactive nitrogen species (RNS) have long been associated with skeletal muscle physiology, their implication in the cell and molecular processes at work during muscle regeneration is more recent. This review focuses on redox regulation during skeletal muscle regeneration. An overview of the basics of ROS/RNS and antioxidant chemistry and biology occurring in skeletal muscle is first provided. Then, the comprehensive knowledge on redox regulation of MuSCs and their surrounding cell partners (macrophages, endothelial cells) during skeletal muscle regeneration is presented in normal muscle and in specific physiological (exercise-induced muscle damage, aging) and pathological (muscular dystrophies) contexts. Recent advances in the comprehension of these processes has led to the development of therapeutic assays using antioxidant supplementation, which result in inconsistent efficiency, underlying the need for new tools that are aimed at precisely deciphering and targeting ROS networks. This review should provide an overall insight of the redox regulation of skeletal muscle regeneration while highlighting the limits of the use of nonspecific antioxidants to improve muscle function. Antioxid. Redox Signal. 00, 000-000.

  9. The making of a muscle.

    PubMed

    Fiorotto, Marta

    2012-06-01

    The skeletal musculature is usually thought of as the primary organ of locomotion, and, like the tyres of a high-performance racing car, their composition, design, preparation and plasticity can make the difference between winner and 'wannabe'. The similarities do not end there, however. Their primary components (cells of the mesodermal layer in the embryo and latex from the rubber tree) begin their existence in locations that can be quite distant from their final point of use and in forms that bear no resemblance to the final product. Their differentiation from primary material to final product entails extensive processing, and the integration of other materials and structures are essential to ensure their function. A fundamental difference, however, is that, in the case of muscle, once the embryo is formed, the progression from relatively undifferentiated mesodermal cells to the final structures is on autopilot, provided there are no contextual aberrations either from genetic or environmental causes. Our current understanding of how muscles develop is a synthesis of observations made on a wide array of organisms, including nematode worms, fruitflies, fish, frogs, birds and various mammals, as well as from the in vitro study of cells isolated from these species. The study of myogenesis in mammals, although less amenable to experimental manipulation, has been facilitated by the recent advances in mouse genetic engineering which has enabled the function of individual genes and cell types to be investigated, as well as the lineage of cells to be traced back to their origin. In this rapid trek through the life of a muscle, how the production of a mature functional muscle from its early inception is orchestrated will be outlined in exceedingly broad strokes so as to convey the wide range of processes that must be engaged in order to generate a functional muscle. Hopefully, enough information will be provided to encourage those interested to explore further.

  10. Effects on contralateral muscles after unilateral electrical muscle stimulation and exercise.

    PubMed

    Song, Yafeng; Forsgren, Sture; Yu, Jiguo; Lorentzon, Ronny; Stål, Per S

    2012-01-01

    It is well established that unilateral exercise can produce contralateral effects. However, it is unclear whether unilateral exercise that leads to muscle injury and inflammation also affects the homologous contralateral muscles. To test the hypothesis that unilateral muscle injury causes contralateral muscle changes, an experimental rabbit model with unilateral muscle overuse caused by a combination of electrical muscle stimulation and exercise (EMS/E) was used. The soleus and gastrocnemius muscles of both exercised and non-exercised legs were analyzed with enzyme- and immunohistochemical methods after 1, 3 and 6 weeks of repeated EMS/E. After 1 w of unilateral EMS/E there were structural muscle changes such as increased variability in fiber size, fiber splitting, internal myonuclei, necrotic fibers, expression of developmental MyHCs, fibrosis and inflammation in the exercised soleus muscle. Only limited changes were found in the exercised gastrocnemius muscle and in both non-exercised contralateral muscles. After 3 w of EMS/E, muscle fiber changes, presence of developmental MyHCs, inflammation, fibrosis and affections of nerve axons and AChE production were observed bilaterally in both the soleus and gastrocnemius muscles. At 6 w of EMS/E, the severity of these changes significantly increased in the soleus muscles and infiltration of fat was observed bilaterally in both the soleus and the gastrocnemius muscles. The affections of the muscles were in all three experimental groups restricted to focal regions of the muscle samples. We conclude that repetitive unilateral muscle overuse caused by EMS/E overtime leads to both degenerative and regenerative tissue changes and myositis not only in the exercised muscles, but also in the homologous non-exercised muscles of the contralateral leg. Although the mechanism behind the contralateral changes is unclear, we suggest that the nervous system is involved in the cross-transfer effects.

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

    PubMed

    Andrade, Bruno M; Baldanza, Marcelo R; Ribeiro, Karla C; Porto, Anderson; Peçanha, Ramon; Fortes, Fabio S A; Zapata-Sudo, Gisele; Campos-de-Carvalho, Antonio C; Goldenberg, Regina C S; Werneck-de-Castro, João Pedro

    2015-01-01

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

  12. Bone Marrow Mesenchymal Cells Improve Muscle Function in a Skeletal Muscle Re-Injury Model

    PubMed Central

    Ribeiro, Karla C.; Porto, Anderson; Peçanha, Ramon; Fortes, Fabio S. A.; Zapata-Sudo, Gisele; Campos-de-Carvalho, Antonio C.; Goldenberg, Regina C. S.; Werneck-de-Castro, João Pedro

    2015-01-01

    Skeletal muscle injury is the most common problem in orthopedic and sports medicine, and severe injury leads to fibrosis and muscle dysfunction. Conventional treatment for successive muscle injury is currently controversial, although new therapies, like cell therapy, seem to be promise. We developed a model of successive injuries in rat to evaluate the therapeutic potential of bone marrow mesenchymal cells (BMMC) injected directly into the injured muscle. Functional and histological assays were performed 14 and 28 days after the injury protocol by isometric tension recording and picrosirius/Hematoxilin & Eosin staining, respectively. We also evaluated the presence and the fate of BMMC on treated muscles; and muscle fiber regeneration. BMMC treatment increased maximal skeletal muscle contraction 14 and 28 days after muscle injury compared to non-treated group (4.5 ± 1.7 vs 2.5 ± 0.98 N/cm2, p<0.05 and 8.4 ± 2.3 vs. 5.7 ± 1.3 N/cm2, p<0.05 respectively). Furthermore, BMMC treatment increased muscle fiber cross-sectional area and the presence of mature muscle fiber 28 days after muscle injury. However, there was no difference in collagen deposition between groups. Immunoassays for cytoskeleton markers of skeletal and smooth muscle cells revealed an apparent integration of the BMMC within the muscle. These data suggest that BMMC transplantation accelerates and improves muscle function recovery in our extensive muscle re-injury model. PMID:26039243

  13. Synchronous monitoring of muscle dynamics and muscle force for maximum isometric tetanus

    NASA Astrophysics Data System (ADS)

    Zakir Hossain, M.; Grill, Wolfgang

    2010-03-01

    Skeletal muscle is a classic example of a biological soft matter . At both macro and microscopic levels, skeletal muscle is exquisitely oriented for force generation and movement. In addition to the dynamics of contracting and relaxing muscle which can be monitored with ultrasound, variations in the muscle force are also expected to be monitored. To observe such force and sideways expansion variations synchronously for the skeletal muscle a novel detection scheme has been developed. As already introduced for the detection of sideways expansion variations of the muscle, ultrasonic transducers are mounted sideways on opposing positions of the monitored muscle. To detect variations of the muscle force, angle of pull of the monitored muscle has been restricted by the mechanical pull of the sonic force sensor. Under this condition, any variation in the time-of-flight (TOF) of the transmitted ultrasonic signals can be introduced by the variation of the path length between the transducers. The observed variations of the TOF are compared to the signals obtained by ultrasound monitoring for the muscle dynamics. The general behavior of the muscle dynamics and muscle force shows almost an identical concept. Since muscle force also relates the psychological boosting-up effects, the influence of boosting-up on muscle force and muscle dynamics can also be quantified form this study. Length-tension or force-length and force-velocity relationship can also be derived quantitatively with such monitoring.

  14. Skeletal muscle metabolism in hypokinetic rats

    NASA Technical Reports Server (NTRS)

    Tischler, M. E.

    1984-01-01

    Muscle growth, protein metabolism, and amino acid metabolism were studied in various groups of rats. Certain groups were adrenaliectomized; some rats were suspended while others (the controls) were weight bearing. Results show that: (1) metabolic changes in the extensor digitorum longus muscle of suspended rats are due primarily to increased circulating glucocorticoids; (2) metabolic changes in the soleus muscle due to higher steroid levels are probably potentiated by greater numbers of steroid receptors; and (3) not all metabolic responses of the soleus muscle to unloading are due to the elevated levels of glucocorticoids or the increased sensitivity of this muscle to these hormones.

  15. Generalized Model of a Skeletal Muscle

    NASA Astrophysics Data System (ADS)

    Shil'ko, S. V.; Chernous, D. A.; Bondarenko, K. K.

    2016-01-01

    A new phenomenological model of a skeletal muscle consisting of a contractile and two nonlinear viscoelastic elements is proposed. The corresponding system of differential equations of the model is obtained, which allows one to derive time-dependent relations between the axial stress and the longitudinal strain in passive and activated states of the muscle. Methods for determining the viscoelastic and functional characteristics of the muscle as input parameters of the equations mentioned above are developed. These methods are based on the joint application of known experimental relations for a single muscle fiber and the results of muscle indentation in vivo on a "Miometer UT 98-01" device.

  16. Human Skeletal Muscle Health with Spaceflight

    NASA Astrophysics Data System (ADS)

    Trappe, Scott

    2012-07-01

    This lecture will overview the most recent aerobic and resistance exercise programs used by crewmembers while aboard the International Space Station (ISS) for six months and examine its effectiveness for protecting skeletal muscle health. Detailed information on the exercise prescription program, whole muscle size, whole muscle performance, and cellular data obtained from muscle biopsy samples will be presented. Historically, detailed information on the exercise program while in space has not been available. These most recent exercise and muscle physiology findings provide a critical foundation to guide the exercise countermeasure program forward for future long-duration space missions.

  17. Membrane fusion in muscle development and repair

    PubMed Central

    Demonbreun, Alexis R.; Biersmith, Bridget H.

    2015-01-01

    Mature skeletal muscle forms from the fusion of skeletal muscle precursor cells, myoblasts. Myoblasts fuse to other myoblasts to generate multinucleate myotubes during myogenesis, and myoblasts also fuse to other myotubes during muscle growth and repair. Proteins within myoblasts and myotubes regulate complex processes such as elongation, migration, cell adherence, cytoskeletal reorganization, membrane coalescence, and ultimately fusion. Recent studies have identified cell surface proteins, intracellular proteins, and extracellular signaling molecules required for the proper fusion of muscle. Many proteins that actively participate in myoblast fusion also coordinate membrane repair. Here we will review mammalian membrane fusion with specific attention to proteins that mediate myoblast fusion and muscle repair. PMID:26537430

  18. Normal Variants: Accessory Muscles About the Ankle.

    PubMed

    Cheung, Yvonne

    2017-02-01

    Accessory muscles around the ankle are commonly encountered as incidental findings on cross-sectional imaging. Mostly asymptomatic, accessory muscles sometimes mimic mass lesions. They have been implicated as the cause of tarsal tunnel syndrome, impingement of surrounding structures, and chronic pain. Distinguishing these muscles can be challenging, because some travel along a similar path. This article describes these accessory muscles in detail, including their relationships to the aponeurosis of the lower leg. An imaging algorithm is proposed to aid in identification of these muscles, providing a valuable tool in diagnostic accuracy and subsequent patient management.

  19. Development of a bedrest muscle stress apparatus

    NASA Technical Reports Server (NTRS)

    Booher, C. R.; Hooper, S. L.; Setzer, D. N.

    1979-01-01

    In attempting further to define the deleterious effects of spaceflight on the human body, measurement systems and techniques were devised to determine the loss of skeletal muscle strength and tone as a result of spaceflight exposure. In order to determine how the muscle degradation process progresses with time during nonuse, a system for measuring muscle stress during bedrest was developed. The Bedrest Muscle Stress Apparatus is configured to slip snugly over the foot board of a standard hospital bed. Data collected with this device correlated well with pre- and post-bedrest data collected with the original skeletal muscle stress apparatus.

  20. Mechanical analysis of Drosophila indirect flight and jump muscles

    PubMed Central

    Swank, Douglas M.

    2011-01-01

    The genetic advantages of Drosophila make it a very appealing choice for investigating muscle development, muscle physiology and muscle protein structure and function. To take full advantage of this model organism, it has been vital to develop isolated Drosophila muscle preparations that can be mechanically evaluated. We describe techniques to isolate, prepare and mechanically analyze skinned muscle fibers from two Drosophila muscle types, the indirect flight muscle and the jump muscle. The function of the indirect flight muscle is similar to vertebrate cardiac muscle, to generate power in an oscillatory manner. The indirect flight muscle is ideal for evaluating the influence of protein mutations on muscle and cross-bridge stiffness, oscillatory power, and deriving cross-bridge rate constants. Jump muscle physiology and structure are more similar to skeletal vertebrate muscle than indirect flight muscle, and it is ideal for measuring maximum shortening velocity, force-velocity characteristics and steady-state power generation. PMID:22079350

  1. Muscle fibre types in the suprahyoid muscles of the rat

    PubMed Central

    COBOS, A. R.; SEGADE, L. A. G.; FUENTES, I.

    2001-01-01

    Five muscle fibre types (I, IIc, IIa, IIx and IIb) were found in the suprahyoid muscles (mylohyoid, geniohyoid, and the anterior and posterior bellies of the digastric) of the rat using immuno and enzyme histochemical techniques. More than 90% of fibres in the muscles examined were fast contracting fibres (types IIa, IIx and IIb). The geniohyoid and the anterior belly of the digastric had the greatest number of IIb fibres, whilst the mylohyoid was almost exclusively formed by aerobic fibres. The posterior belly of the digastric contained a greater percentage of aerobic fibres (83.4%) than the anterior belly (67.8%). With the exception of the geniohyoid, the percentage of type I and IIc fibres, which have slow myosin heavy chain (MHCβ), was relatively high and greater than has been previously reported in the jaw-closing muscles of the rat, such as the superficial masseter. The geniohyoid and mylohyoid exhibited a mosaic fibre type distribution, without any apparent regionalisation, although in the later MHCβ-containing fibres (types I and IIc) were primarily located in the rostral 2/3 region. In contrast, the anterior and posterior bellies of the digastric revealed a clear regionalisation. In the anterior belly of the digastric 2 regions were observed: both a central region, which was almost exclusively formed by aerobic fibres and where all of the type I and IIc fibres were located, and a peripheral region, where type IIb fibres predominated. The posterior belly of the digastric showed a deep aerobic region which was greater in size and where type I and IIc fibres were confined, and a superficial region, where primarily type IIx and IIb fibres were observed. PMID:11322721

  2. Muscle coordination is habitual rather than optimal.

    PubMed

    de Rugy, Aymar; Loeb, Gerald E; Carroll, Timothy J

    2012-05-23

    When sharing load among multiple muscles, humans appear to select an optimal pattern of activation that minimizes costs such as the effort or variability of movement. How the nervous system achieves this behavior, however, is unknown. Here we show that contrary to predictions from optimal control theory, habitual muscle activation patterns are surprisingly robust to changes in limb biomechanics. We first developed a method to simulate joint forces in real time from electromyographic recordings of the wrist muscles. When the model was altered to simulate the effects of paralyzing a muscle, the subjects simply increased the recruitment of all muscles to accomplish the task, rather than recruiting only the useful muscles. When the model was altered to make the force output of one muscle unusually noisy, the subjects again persisted in recruiting all muscles rather than eliminating the noisy one. Such habitual coordination patterns were also unaffected by real modifications of biomechanics produced by selectively damaging a muscle without affecting sensory feedback. Subjects naturally use different patterns of muscle contraction to produce the same forces in different pronation-supination postures, but when the simulation was based on a posture different from the actual posture, the recruitment patterns tended to agree with the actual rather than the simulated posture. The results appear inconsistent with computation of motor programs by an optimal controller in the brain. Rather, the brain may learn and recall command programs that result in muscle coordination patterns generated by lower sensorimotor circuitry that are functionally "good-enough."

  3. Pathophysiology of muscle dysfunction in COPD.

    PubMed

    Gea, Joaquim; Agustí, Alvar; Roca, Josep

    2013-05-01

    Muscle dysfunction often occurs in patients with chronic obstructive pulmonary disease (COPD) and may involve both respiratory and locomotor (peripheral) muscles. The loss of strength and/or endurance in the former can lead to ventilatory insufficiency, whereas in the latter it limits exercise capacity and activities of daily life. Muscle dysfunction is the consequence of complex interactions between local and systemic factors, frequently coexisting in COPD patients. Pulmonary hyperinflation along with the increase in work of breathing that occur in COPD appear as the main contributing factors to respiratory muscle dysfunction. By contrast, deconditioning seems to play a key role in peripheral muscle dysfunction. However, additional systemic factors, including tobacco smoking, systemic inflammation, exercise, exacerbations, nutritional and gas exchange abnormalities, anabolic insufficiency, comorbidities and drugs, can also influence the function of both respiratory and peripheral muscles, by inducing modifications in their local microenvironment. Under all these circumstances, protein metabolism imbalance, oxidative stress, inflammatory events, as well as muscle injury may occur, determining the final structure and modulating the function of different muscle groups. Respiratory muscles show signs of injury as well as an increase in several elements involved in aerobic metabolism (proportion of type I fibers, capillary density, and aerobic enzyme activity) whereas limb muscles exhibit a loss of the same elements, injury, and a reduction in fiber size. In the present review we examine the current state of the art of the pathophysiology of muscle dysfunction in COPD.

  4. Muscle structural assembly and functional consequences.

    PubMed

    Narici, Marco; Franchi, Martino; Maganaris, Constantinos

    2016-01-01

    The relationship between muscle structure and function has been a matter of investigation since the Renaissance period. Extensive use of anatomical dissections and the introduction of the scientific method enabled early scholars to lay the foundations of muscle physiology and biomechanics. Progression of knowledge in these disciplines led to the current understanding that muscle architecture, together with muscle fibre contractile properties, has a major influence on muscle mechanical properties. Recently, advances in laser diffraction, optical microendoscopy and ultrasonography have enabled in vivo investigations into the behaviour of human muscle fascicles and sarcomeres with varying joint angle and muscle contraction intensity. With these technologies it has become possible to identify the length region over which fascicles and sarcomeres develop maximum isometric force in vivo as well as the operating ranges of fascicles and sarcomeres during real-life activities such as walking. Also, greater insights into the remodelling of muscle architecture in response to overloading and unloading, and in ageing, have been obtained by the use of ultrasonography; these have led to the identification of clinical biomarkers of disuse atrophy and sarcopenia. Recent evidence also shows that the pattern of muscle hypertrophy in response to chronic loading is contraction-mode dependent (eccentric versus concentric), as similar gains in muscle mass, but through differing addition of sarcomeres in series and in parallel (as indirectly inferred from changes in fascicle length and pennation angle), have been found. These innovative observations prompted a new set of investigations into the molecular mechanisms regulating this contraction-specific muscle growth.

  5. Myosin filament structure in vertebrate smooth muscle

    PubMed Central

    1996-01-01

    The in vivo structure of the myosin filaments in vertebrate smooth muscle is unknown. Evidence from purified smooth muscle myosin and from some studies of intact smooth muscle suggests that they may have a nonhelical, side-polar arrangement of crossbridges. However, the bipolar, helical structure characteristic of myosin filaments in striated muscle has not been disproved for smooth muscle. We have used EM to investigate this question in a functionally diverse group of smooth muscles (from the vascular, gastrointestinal, reproductive, and visual systems) from mammalian, amphibian, and avian species. Intact muscle under physiological conditions, rapidly frozen and then freeze substituted, shows many myosin filaments with a square backbone in transverse profile. Transverse sections of fixed, chemically skinned muscles also show square backbones and, in addition, reveal projections (crossbridges) on only two opposite sides of the square. Filaments gently isolated from skinned smooth muscles and observed by negative staining show crossbridges with a 14.5-nm repeat projecting in opposite directions on opposite sides of the filament. Such filaments subjected to low ionic strength conditions show bare filament ends and an antiparallel arrangement of myosin tails along the length of the filament. All of these observations are consistent with a side-polar structure and argue against a bipolar, helical crossbridge arrangement. We conclude that myosin filaments in all smooth muscles, regardless of function, are likely to be side-polar. Such a structure could be an important factor in the ability of smooth muscles to contract by large amounts. PMID:8698822

  6. Impact of weightlessness on muscle function

    NASA Technical Reports Server (NTRS)

    Tischler, M. E.; Slentz, M.

    1995-01-01

    The most studied skeletal muscles which depend on gravity, "antigravity" muscles, are located in the posterior portion of the legs. Antigravity muscles are characterized generally by a different fiber type composition than those which are considered nonpostural. The gravity-dependent function of the antigravity muscles makes them particularly sensitive to weightlessness (unweighting) resulting in a substantial loss of muscle protein, with a relatively greater loss of myofibrillar (structural) proteins. Accordingly alpha-actin mRNA decreases in muscle of rats exposed to microgravity. In the legs, the soleus seems particularly responsive to the lack of weight-bearing associated with space flight. The loss of muscle protein leads to a decreased cross-sectional area of muscle fibers, particularly of the slow-twitch, oxidative (SO) ones compared to fast-twitch glycolytic (FG) or oxidative-glycolytic (FOG) fibers. In some muscles, a shift in fiber composition from SO to FOG has been reported in the adaptation to spaceflight. Changes in muscle composition with spaceflight have been associated with decreased maximal isometric tension (Po) and increased maximal shortening velocity. In terms of fuel metabolism, results varied depending on the pathway considered. Glucose uptake, in the presence of insulin, and activities of glycolytic enzymes are increased by space flight. In contrast, oxidation of fatty acids may be diminished. Oxidation of pyruvate, activity of the citric acid cycle, and ketone metabolism in muscle seem to be unaffected by microgravity.

  7. Spinalis capitis, or an accessory paraspinous muscle?

    PubMed Central

    Martin, A

    1994-01-01

    A unilateral muscle, the location and dimensions of which do not exactly conform to existing descriptions, was found during dissection of the suboccipital region. The muscle in question extended from the spine and transverse process of the 6th cervical vertebra to the base of the skull. At its rostral attachment it blended with the insertion of the left rectus capitis posterior minor muscle on the inferior nuchal line. The caudal attachment arched over the semispinalis cervicis, separated from that muscle by an extensive venous complex. Medially, along the length of the muscle, weak fascial attachments to the ligamentum nuchae were present. Arterial branches from the occipital artery entered the muscle near its rostral end and nerve fibres and vascular channels from the lower cervical region entered the deep surface of the muscle. Images Figs 1-3 Fig. 4 PMID:7559114

  8. Proteomic profiling of skeletal muscle plasticity.

    PubMed

    Ohlendieck, Kay

    2011-10-01

    One of the most striking physiological features of skeletal muscle tissues are their enormous capacity to adapt to changed functional demands. Muscle plasticity has been extensively studied by histological, biochemical, physiological and genetic methods over the last few decades. With the recent emergence of high-throughput and large-scale proteomic techniques, mass spectrometry-based surveys have also been applied to the global analysis of the skeletal muscle protein complement during physiological modifications and pathophysiological alterations. This review outlines and discusses the impact of recent proteomic profiling studies of skeletal muscle transitions, including the effects of chronic electro-stimulation, physical exercise, denervation, disuse atrophy, hypoxia, myotonia, motor neuron disease and age-related fibre type shifting. This includes studies on the human skeletal muscle proteome, animal models of muscle plasticity and major neuromuscular pathologies. The biomedical importance of establishing reliable biomarker signatures for the various molecular and cellular transition phases involved in muscle transformation is critically examined.

  9. Satellite cells in human skeletal muscle plasticity.

    PubMed

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

    2015-01-01

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

  10. Muscle development in thyroidectomised chickens (Gallus domesticus).

    PubMed

    Moore, G E; Harvey, S; Klandorf, H; Goldspink, G

    1984-08-01

    The metabolic and contractile activity of muscle was determined in immature cockerels made hypothyroid by surgical thyroidectomy at 6 weeks of age. Four weeks after thyroidectomy the activity of Mg2+-activated myofibrillar ATPase and total phosphorylase was reduced in the fast-phasic, posterior latissimus dorsi (PLD) and scapulotriceps (ST) muscles. The activities of these enzymes were unaffected in the slow-tonic, anterior latissimus dorsi (ALD) muscle. Thyroidectomy had no effect on length of the muscles studied but reduced the weight of the ALD and ST muscles. These results suggest that hypothyroidism results in a "slowing down" of fast-phasic muscles, although it does not affect the activity of slow-tonic muscles.

  11. Rotaxane-based molecular muscles.

    PubMed

    Bruns, Carson J; Stoddart, J Fraser

    2014-07-15

    CONSPECTUS: More than two decades of investigating the chemistry of bistable mechanically interlocked molecules (MIMs), such as rotaxanes and catenanes, has led to the advent of numerous molecular switches that express controlled translational or circumrotational movement on the nanoscale. Directed motion at this scale is an essential feature of many biomolecular assemblies known as molecular machines, which carry out essential life-sustaining functions of the cell. It follows that the use of bistable MIMs as artificial molecular machines (AMMs) has been long anticipated. This objective is rarely achieved, however, because of challenges associated with coupling the directed motions of mechanical switches with other systems on which they can perform work. A natural source of inspiration for designing AMMs is muscle tissue, since it is a material that relies on the hierarchical organization of molecular machines (myosin) and filaments (actin) to produce the force and motion that underpin locomotion, circulation, digestion, and many other essential life processes in humans and other animals. Muscle is characterized at both microscopic and macroscopic length scales by its ability to generate forces that vary the distance between two points at the expense of chemical energy. Artificial muscles that mimic this ability are highly sought for applications involving the transduction of mechanical energy. Rotaxane-based molecular switches are excellent candidates for artificial muscles because their architectures intrinsically possess movable filamentous molecular components. In this Account, we describe (i) the different types of rotaxane "molecular muscle" architectures that express contractile and extensile motion, (ii) the molecular recognition motifs and corresponding stimuli that have been used to actuate them, and (iii) the progress made on integrating and scaling up these motions for potential applications. We identify three types of rotaxane muscles, namely, "daisy

  12. Structure of giant muscle proteins

    PubMed Central

    Meyer, Logan C.; Wright, Nathan T.

    2013-01-01

    Giant muscle proteins (e.g., titin, nebulin, and obscurin) play a seminal role in muscle elasticity, stretch response, and sarcomeric organization. Each giant protein consists of multiple tandem structural domains, usually arranged in a modular fashion spanning 500 kDa to 4 MDa. Although many of the domains are similar in structure, subtle differences create a unique function of each domain. Recent high and low resolution structural and dynamic studies now suggest more nuanced overall protein structures than previously realized. These findings show that atomic structure, interactions between tandem domains, and intrasarcomeric environment all influence the shape, motion, and therefore function of giant proteins. In this article we will review the current understanding of titin, obscurin, and nebulin structure, from the atomic level through the molecular level. PMID:24376425

  13. Tonic muscle pain does not increase fusimotor drive to human leg muscles: implications for chronic muscle pain.

    PubMed

    Fazalbhoy, Azharuddin; Macefield, Vaughan G; Birznieks, Ingvars

    2013-06-01

    Experimental pain induced in animals has shown that noxious stimulation of group III and IV afferents increases the firing of muscle spindles via a reflex excitation of fusimotor (γ) motoneurones. Chronic muscle pain has been hypothesized to develop as a result of a vicious cycle involving this mechanism. In order to explore the effects of long-lasting muscle pain on the fusimotor system, single unit muscle spindle afferents were recorded from 15 subjects. Afferent activity was recorded from foot and ankle extensor muscles whilst infusing hypertonic saline into the tibialis anterior muscle of the ipsilateral leg, producing moderate-strong pain lasting for ∼60 min. A change in fusimotor drive was inferred by observing changes in the mean discharge rate of spontaneously active muscle spindle afferents. Homonymous and heteronymous muscles remained relaxed and showed no increase in activity, arguing against any fusimotor-driven increase in motor activity, and there was no net change in the firing of muscle spindle afferents. We conclude that long-lasting stimulation of group III and IV afferents fails to excite fusimotor neurones and increase muscle spindle discharge. Accordingly, the vicious cycle theory has no functional basis for the development of myalgia in human subjects.

  14. Intracellular acidosis enhances the excitability of working muscle.

    PubMed

    Pedersen, Thomas H; Nielsen, Ole B; Lamb, Graham D; Stephenson, D George

    2004-08-20

    Intracellular acidification of skeletal muscles is commonly thought to contribute to muscle fatigue. However, intracellular acidosis also acts to preserve muscle excitability when muscles become depolarized, which occurs with working muscles. Here, we show that this process may be mediated by decreased chloride permeability, which enables action potentials to still be propagated along the internal network of tubules in a muscle fiber (the T system) despite muscle depolarization. These results implicate chloride ion channels in muscle function and emphasize that intracellular acidosis of muscle has protective effects during muscle fatigue.

  15. Highly efficient, functional engraftment of skeletal muscle stem cells in dystrophic muscles.

    PubMed

    Cerletti, Massimiliano; Jurga, Sara; Witczak, Carol A; Hirshman, Michael F; Shadrach, Jennifer L; Goodyear, Laurie J; Wagers, Amy J

    2008-07-11

    Satellite cells reside beneath the basal lamina of skeletal muscle fibers and include cells that act as precursors for muscle growth and repair. Although they share a common anatomical localization and typically are considered a homogeneous population, satellite cells actually exhibit substantial heterogeneity. We used cell-surface marker expression to purify from the satellite cell pool a distinct population of skeletal muscle precursors (SMPs) that function as muscle stem cells. When engrafted into muscle of dystrophin-deficient mdx mice, purified SMPs contributed to up to 94% of myofibers, restoring dystrophin expression and significantly improving muscle histology and contractile function. Transplanted SMPs also entered the satellite cell compartment, renewing the endogenous stem cell pool and participating in subsequent rounds of injury repair. Together, these studies indicate the presence in adult skeletal muscle of prospectively isolatable muscle-forming stem cells and directly demonstrate the efficacy of myogenic stem cell transplant for treating muscle degenerative disease.

  16. Myofascial force transmission between transferred rat flexor carpi ulnaris muscle and former synergistic palmaris longus muscle

    PubMed Central

    Maas, Huub; Huijing, Peter A.

    2011-01-01

    Summary We investigated the extent of mechanical interaction between rat flexor carpi ulnaris (FCU) and palmaris longus (PL) muscles following transfer of FCU to the distal tendons of extensor carpi radialis brevis and longus (ECRB/L) muscles. Five weeks after recovery from surgery, isometric forces exerted at the distal tendons of FCU and PL were quantified at various FCU lengths. PL was kept at a constant length. Changing the muscle-tendon complex length of transferred FCU (by maximally 3.5 mm) decreased PL force significantly (by 7%). A linear relationship was found between changes in FCU muscle belly length, being a measure of muscle relative positions, and PL force. These results indicate that despite transfer of FCU muscle to the extensor side of the forearm, changing FCU length still affects force transmission of its, now, antagonistic PL muscle. We conclude that a transferred muscle may still be mechanically linked to its former synergistic muscles. PMID:23738260

  17. Semimembranosus muscle herniation: a rare case with emphasis on muscle biomechanics.

    PubMed

    Naffaa, Lena; Moukaddam, Hicham; Samim, Mohammad; Lemieux, Aaron; Smitaman, Edward

    2017-03-01

    Muscle herniations are rare and most reported cases involve muscles of the lower leg. We use a case of muscle herniation involving the semimembranosus muscle, presenting as a painful mass in an adolescent male after an unspecified American football injury, to highlight a simple concept of muscle biomechanics as it pertains to muscle hernia(s): decreased traction upon muscle fibers can increase conspicuity of muscle herniation(s)-this allows a better understanding of the apt provocative maneuvers to employ, during dynamic ultrasound or magnetic resonance imaging, in order to maximize diagnostic yield and, thereby, limit patient morbidity related to any muscle herniation. Our patient subsequently underwent successful decompressive fasciotomy and has since returned to his normal daily activities.

  18. Muscle quality in aging: a multi-dimensional approach to muscle functioning with applications for treatment.

    PubMed

    Fragala, Maren S; Kenny, Anne M; Kuchel, George A

    2015-05-01

    Aging is often accompanied by declines in physical functioning which impedes older adults' quality of life, sense of independence, and ability to perform daily tasks. Age-related decreases in skeletal muscle quantity, termed sarcopenia, have traditionally been blamed for these physical decrements. However, recent evidence suggests that the quality of muscle tissue may be more functionally relevant than its quantity. 'Muscle quality' has been emerging as a means to elucidate and describe the intricate intramuscular changes associated with muscle performance in the context of aging and sarcopenia. While muscle quality has most commonly been defined in terms of muscle composition or relative strength, at the core, muscle quality really describes muscle's ability to function. Skeletal muscle displays a strong structure-function relationship by which several architectural characteristics factor into its functional capacity. This review describes the structural, physiological, and functional determinants of muscle quality at the tissue and cellular level, while also introducing other novel parameters such as sarcomere spacing and integrity, circulating biomarkers, and the muscle quality index. Muscle qualitative features are described from the perspective of how physical exercise may improve muscle quality in older adults. This broad, multidimensional perspective of muscle quality in the context of aging and sarcopenia offers comprehensive insights for consideration and integration in developing improved prognostic tools for research and clinical care, while also promoting translational approaches to the design of novel targeted intervention strategies designed to maintain function and mobility into late life.

  19. An allometric analysis of the number of muscle spindles in mammalian skeletal muscles.

    PubMed

    Banks, R W

    2006-06-01

    An allometric analysis of the number of muscle spindles in relation to muscle mass in mammalian (mouse, rat, guinea-pig, cat, human) skeletal muscles is presented. It is shown that the trend to increasing number as muscle mass increases follows an isometric (length) relationship between species, whereas within a species, at least for the only essentially complete sample (human), the number of spindles scales, on average, with the square root rather than the cube root of muscle mass. An attempt is made to reconcile these apparently discrepant relationships. Use of the widely accepted spindle density (number of spindles g(-1) of muscle) as a measure of relative abundance of spindles in different muscles is shown to be grossly misleading. It is replaced with the residuals of the linear regression of ln spindle number against ln muscle mass. Significant differences in relative spindle abundance as measured by residuals were found between regional groups of muscles: the greatest abundance is in axial muscles, including those concerned with head position, whereas the least is in muscles of the shoulder girdle. No differences were found between large and small muscles operating in parallel, or between antigravity and non-antigravity muscles. For proximal vs. distal muscles, spindles were significantly less abundant in the hand than the arm, but there was no difference between the foot and the leg.

  20. The effects of Juchumseogi and Juchumseo Jireugi motions of taekwondo on muscle activation of paraspinal muscles.

    PubMed

    Baek, Jongmyeng; Lee, Jaeseok; Kim, Jonghyun; Kim, Jeonghun; Han, Dongwook; Byun, Sunghak

    2015-09-01

    [Purpose] The purpose of this study is to examine the effects of Juchumseogi and Juchumseo Jireugi motions on muscle activation of the paraspinal muscles. [Subjects] The subjects of this study were 20 healthy male students who listened to an explanation of the study methods and the purpose of the experiment, and agreed to participate in the study. [Methods] Muscle activation measurements of the paraspinal muscles at C3, T7, and L3 were taken while standing still and while performing Juchumseogi and Juchumseo Jireugi movements. The Juchumseogi and Juchumseo Jireugi motions were performed 3 times, and its mean value was used for analysis. [Results] The right and left muscle activation of paraspinal muscles induced by Juchumseogi and Juchumseo Jireugi motions in C3 and T7 were significantly higher than those induced by just standing. Muscle activation of paraspinal muscles induced by Juchumseo Jireugi motions in C3, T7, and L3 were significantly higher than those induced by Juchumseogi alone. The right and left muscle activation of paraspinal muscles induced by Juchumseo Jireugi motion in C3, T7, and L3 were significantly higher than those induced by standing and Juchumseogi alone. [Conclusion] This study demonstrated that Juchumseogi and Juchumseo Jireugi motions of Taekwondo could increase muscle activation of paraspinal muscles, and Juchumseo Jireugi motions were more effective for enhancing muscle activation of paraspinal muscles.

  1. Determining all parameters necessary to build Hill-type muscle models from experiments on single muscles.

    PubMed

    Blümel, Marcus; Hooper, Scott L; Guschlbauerc, Christoph; White, William E; Büschges, Ansgar

    2012-11-01

    Characterizing muscle requires measuring such properties as force-length, force-activation, and force-velocity curves. These characterizations require large numbers of data points because both what type of function (e.g., linear, exponential, hyperbolic) best represents each property, and the values of the parameters in the relevant equations, need to be determined. Only a few properties are therefore generally measured in experiments on any one muscle, and complete characterizations are obtained by averaging data across a large number of muscles. Such averaging approaches can work well for muscles that are similar across individuals. However, considerable evidence indicates that large inter-individual variation exists, at least for some muscles. This variation poses difficulties for across-animal averaging approaches. Methods to fully describe all muscle's characteristics in experiments on individual muscles would therefore be useful. Prior work in stick insect extensor muscle has identified what functions describe each of this muscle's properties and shown that these equations apply across animals. Characterizing these muscles on an individual-by-individual basis therefore requires determining only the values of the parameters in these equations, not equation form. We present here techniques that allow determining all these parameter values in experiments on single muscles. This technique will allow us to compare parameter variation across individuals and to model muscles individually. Similar experiments can likely be performed on single muscles in other systems. This approach may thus provide a widely applicable method for characterizing and modeling muscles from single experiments.

  2. The effects of Juchumseogi and Juchumseo Jireugi motions of taekwondo on muscle activation of paraspinal muscles

    PubMed Central

    Baek, Jongmyeng; Lee, Jaeseok; Kim, Jonghyun; Kim, Jeonghun; Han, Dongwook; Byun, Sunghak

    2015-01-01

    [Purpose] The purpose of this study is to examine the effects of Juchumseogi and Juchumseo Jireugi motions on muscle activation of the paraspinal muscles. [Subjects] The subjects of this study were 20 healthy male students who listened to an explanation of the study methods and the purpose of the experiment, and agreed to participate in the study. [Methods] Muscle activation measurements of the paraspinal muscles at C3, T7, and L3 were taken while standing still and while performing Juchumseogi and Juchumseo Jireugi movements. The Juchumseogi and Juchumseo Jireugi motions were performed 3 times, and its mean value was used for analysis. [Results] The right and left muscle activation of paraspinal muscles induced by Juchumseogi and Juchumseo Jireugi motions in C3 and T7 were significantly higher than those induced by just standing. Muscle activation of paraspinal muscles induced by Juchumseo Jireugi motions in C3, T7, and L3 were significantly higher than those induced by Juchumseogi alone. The right and left muscle activation of paraspinal muscles induced by Juchumseo Jireugi motion in C3, T7, and L3 were significantly higher than those induced by standing and Juchumseogi alone. [Conclusion] This study demonstrated that Juchumseogi and Juchumseo Jireugi motions of Taekwondo could increase muscle activation of paraspinal muscles, and Juchumseo Jireugi motions were more effective for enhancing muscle activation of paraspinal muscles. PMID:26504295

  3. Channelopathies of skeletal muscle excitability

    PubMed Central

    Cannon, Stephen C.

    2016-01-01

    Familial disorders of skeletal muscle excitability were initially described early in the last century and are now known to be caused by mutations of voltage-gated ion channels. The clinical manifestations are often striking, with an inability to relax after voluntary contraction (myotonia) or transient attacks of severe weakness (periodic paralysis). An essential feature of these disorders is fluctuation of symptoms that are strongly impacted by environmental triggers such as exercise, temperature, or serum K+ levels. These phenomena have intrigued physiologists for decades, and in the past 25 years the molecular lesions underlying these disorders have been identified and mechanistic studies are providing insights for therapeutic strategies of disease modification. These familial disorders of muscle fiber excitability are “channelopathies” caused by mutations of a chloride channel (ClC-1), sodium channel (NaV1.4), calcium channel (CaV1.1) and several potassium channels (Kir2.1, Kir2.6, Kir3.4). This review provides a synthesis of the mechanistic connections between functional defects of mutant ion channels, their impact on muscle excitability, how these changes cause clinical phenotypes, and approaches toward therapeutics. PMID:25880512

  4. Muscle disuse atrophy is not accompanied by changes in skeletal muscle satellite cell content.

    PubMed

    Snijders, Tim; Wall, Benjamin T; Dirks, Marlou L; Senden, Joan M G; Hartgens, Fred; Dolmans, John; Losen, Mario; Verdijk, Lex B; van Loon, Luc J C

    2014-04-01

    Muscle disuse leads to a considerable loss in skeletal muscle mass and strength. However, the cellular mechanisms underlying disuse-induced muscle fibre atrophy remain to be elucidated. Therefore we assessed the effect of muscle disuse on the CSA (cross-sectional area), muscle fibre size, satellite cell content and associated myocellular signalling pathways of the quadriceps muscle. A total of 12 healthy young (24±1 years of age) men were subjected to 2 weeks of one-legged knee immobilization via a full-leg cast. Before and immediately after the immobilization period and after 6 weeks of natural rehabilitation, muscle strength [1RM (one-repetition maximum)], muscle CSA [single slice CT (computed tomography) scan] and muscle fibre type characteristics (muscle biopsies) were assessed. Protein and/or mRNA expression of key genes [i.e. MYOD (myogenic differentiation), MYOG (myogenin) and MSTN (myostatin)] in the satellite cell regulatory pathways were determined using Western blotting and RT-PCR (real-time PCR) analyses respectively. The present study found that quadriceps CSA declined following immobilization by 8±2% (P<0.05). In agreement, both type I and type II muscle fibre size decreased 7±3% and 13±4% respectively (P<0.05). No changes were observed in satellite cell content following immobilization in either type I or type II muscle fibres. Muscle MYOG mRNA expression doubled (P<0.05), whereas MSTN protein expression decreased 30±9% (P<0.05) following immobilization. Muscle mass and strength returned to the baseline values within 6 weeks of recovery without any specific rehabilitative programme. In conclusion, 2 weeks of muscle disuse leads to considerable loss in skeletal muscle mass and strength. The loss in muscle mass was attributed to both type I and type II muscle fibre atrophy, and was not accompanied by a decline in satellite cell content.

  5. Muscle spindles in human tibialis anterior encode muscle fascicle length changes.

    PubMed

    Day, James; Bent, Leah R; Birznieks, Ingvars; Macefield, Vaughan G; Cresswell, Andrew G

    2017-04-01

    Muscle spindles provide exquisitely sensitive proprioceptive information regarding joint position and movement. Through passively driven length changes in the muscle-tendon unit (MTU), muscle spindles detect joint rotations because of their in-parallel mechanical linkage to muscle fascicles. In human microneurography studies, muscle fascicles are assumed to follow the MTU and, as such, fascicle length is not measured in such studies. However, under certain mechanical conditions, compliant structures can act to decouple the fascicles, and, therefore, the spindles, from the MTU. Such decoupling may reduce the fidelity by which muscle spindles encode joint position and movement. The aim of the present study was to measure, for the first time, both the changes in firing of single muscle spindle afferents and changes in muscle fascicle length in vivo from the tibialis anterior muscle (TA) during passive rotations about the ankle. Unitary recordings were made from 15 muscle spindle afferents supplying TA via a microelectrode inserted into the common peroneal nerve. Ultrasonography was used to measure the length of an individual fascicle of TA. We saw a strong correlation between fascicle length and firing rate during passive ankle rotations of varying rates (0.1-0.5 Hz) and amplitudes (1-9°). In particular, we saw responses observed at relatively small changes in muscle length that highlight the sensitivity of the TA muscle to small length changes. This study is the first to measure spindle firing and fascicle dynamics in vivo and provides an experimental basis for further understanding the link between fascicle length, MTU length, and spindle firing patterns.NEW & NOTEWORTHY Muscle spindles are exquisitely sensitive to changes in muscle length, but recordings from human muscle spindle afferents are usually correlated with joint angle rather than muscle fascicle length. In this study, we monitored both muscle fascicle length and spindle firing from the human tibialis

  6. Skeletal muscle transverse strain during isometric contraction at different lengths.

    PubMed

    van Donkelaar, C C; Willems, P J; Muijtjens, A M; Drost, M R

    1999-08-01

    An important assumption in 2D numerical models of skeletal muscle contraction involves deformation in the third dimension of the included muscle section. The present paper studies the often used plane strain description. Therefore, 3D muscle surface deformation is measured from marker displacements during isometric contractions at various muscle lengths. Longitudinal strains at superficial muscle fibers ( - 14 +/- 2.6% at L0, n = 57) and aponeurosis (0.8 +/- 0.9% at L0) decrease with increasing muscle length. The same holds for transverse muscle surface strains in superficial muscle fibers and aponeurosis, which are comparable at intermediate muscle length, but differ at long and short muscle length. Because transverse strains during isometric contraction change with initial muscle length, it is concluded that the effect of muscle length on muscle deformation cannot be studied in plane strain models. These results do not counteract the use of these models to study deformation in contractions with approximately - 9 % longitudinal muscle fiber strain, as transverse strain in superficial muscle fibers and in aponeurosis tissue is minimal in that case. Aponeurosis surface area change decreases with increasing initial muscle length, but muscle fiber surface area change is - 11%, independent of muscle length. Assuming incompressible muscle material, this means that strain perpendicular to the muscle surface equals 11%. Taking the relationship between transverse and longitudinal muscle fiber strain into account, it is hypothesized that superficial muscle fibers flatten during isometric contractions.

  7. Aging of human muscle: understanding sarcopenia at the single muscle cell level.

    PubMed

    Frontera, Walter R; Zayas, Ana Rodriguez; Rodriguez, Natividad

    2012-02-01

    The loss of muscle mass with age, also known as sarcopenia, is a major scientific and public health problem. Muscle atrophy is associated with the loss of functional capacity and poor health outcomes in elderly men and women. A detailed understanding of this problem in humans can be enhanced by the use of experiments with single muscle fibers. It is likely that both muscle atrophy and a decrease in muscle-fiber quality contribute to muscle dysfunction among the elderly. A better understanding of sarcopenia at the single-fiber level may lead to the design of more effective rehabilitative interventions.

  8. Mammalian masticatory muscles: homology, nomenclature, and diversification.

    PubMed

    Druzinsky, Robert E; Doherty, Alison H; De Vree, Frits L

    2011-08-01

    There is a deep and rich literature of comparative studies of jaw muscles in mammals but no recent analyses employ modern phylogenetic techniques to better understand evolutionary changes that have occurred in these muscles. In order to fully develop and utilize the Feeding Experiments End-user Database (FEED), we are constructing a comprehensive ontology of mammalian jaw muscles. This process has led to a careful consideration of nomenclature and homologies of the muscles and their constituent parts. Precise determinations of muscle attachments have shown that muscles with similar names are not necessarily homologous. Using new anatomical descriptions derived from the literature, we defined character states for the jaw muscles in diverse mammalian species. We then mapped those characters onto a recent phylogeny of mammals with the aid of the Mesquite software package. Our data further elucidate how muscle groups associated with the feeding apparatus differ and have become highly specialized in certain mammalian orders, such as Rodentia, while remaining conserved in other orders. We believe that careful naming of muscles and statistical analyses of their distributions among mammals, in association with the FEED database, will lead to new, significant insights into the functional, structural, and evolutionary morphology of the jaw muscles.

  9. Space travel directly induces skeletal muscle atrophy.

    PubMed

    Vandenburgh, H; Chromiak, J; Shansky, J; Del Tatto, M; Lemaire, J

    1999-06-01

    Space travel causes rapid and pronounced skeletal muscle wasting in humans that reduces their long-term flight capabilities. To develop effective countermeasures, the basis of this atrophy needs to be better understood. Space travel may cause muscle atrophy indirectly by altering circulating levels of factors such as growth hormone, glucocorticoids, and anabolic steroids and/or by a direct effect on the muscle fibers themselves. To determine whether skeletal muscle cells are directly affected by space travel, tissue-cultured avian skeletal muscle cells were tissue engineered into bioartificial muscles and flown in perfusion bioreactors for 9 to 10 days aboard the Space Transportation System (STS, i.e., Space Shuttle). Significant muscle fiber atrophy occurred due to a decrease in protein synthesis rates without alterations in protein degradation. Return of the muscle cells to Earth stimulated protein synthesis rates of both muscle-specific and extracellular matrix proteins relative to ground controls. These results show for the first time that skeletal muscle fibers are directly responsive to space travel and should be a target for countermeasure development.

  10. Muscle activity characterization by laser Doppler Myography

    NASA Astrophysics Data System (ADS)

    Scalise, Lorenzo; Casaccia, Sara; Marchionni, Paolo; Ercoli, Ilaria; Primo Tomasini, Enrico

    2013-09-01

    Electromiography (EMG) is the gold-standard technique used for the evaluation of muscle activity. This technique is used in biomechanics, sport medicine, neurology and rehabilitation therapy and it provides the electrical activity produced by skeletal muscles. Among the parameters measured with EMG, two very important quantities are: signal amplitude and duration of muscle contraction, muscle fatigue and maximum muscle power. Recently, a new measurement procedure, named Laser Doppler Myography (LDMi), for the non contact assessment of muscle activity has been proposed to measure the vibro-mechanical behaviour of the muscle. The aim of this study is to present the LDMi technique and to evaluate its capacity to measure some characteristic features proper of the muscle. In this paper LDMi is compared with standard superficial EMG (sEMG) requiring the application of sensors on the skin of each patient. sEMG and LDMi signals have been simultaneously acquired and processed to test correlations. Three parameters has been analyzed to compare these techniques: Muscle activation timing, signal amplitude and muscle fatigue. LDMi appears to be a reliable and promising measurement technique allowing the measurements without contact with the patient skin.

  11. Space travel directly induces skeletal muscle atrophy

    NASA Technical Reports Server (NTRS)

    Vandenburgh, H.; Chromiak, J.; Shansky, J.; Del Tatto, M.; Lemaire, J.

    1999-01-01

    Space travel causes rapid and pronounced skeletal muscle wasting in humans that reduces their long-term flight capabilities. To develop effective countermeasures, the basis of this atrophy needs to be better understood. Space travel may cause muscle atrophy indirectly by altering circulating levels of factors such as growth hormone, glucocorticoids, and anabolic steroids and/or by a direct effect on the muscle fibers themselves. To determine whether skeletal muscle cells are directly affected by space travel, tissue-cultured avian skeletal muscle cells were tissue engineered into bioartificial muscles and flown in perfusion bioreactors for 9 to 10 days aboard the Space Transportation System (STS, i.e., Space Shuttle). Significant muscle fiber atrophy occurred due to a decrease in protein synthesis rates without alterations in protein degradation. Return of the muscle cells to Earth stimulated protein synthesis rates of both muscle-specific and extracellular matrix proteins relative to ground controls. These results show for the first time that skeletal muscle fibers are directly responsive to space travel and should be a target for countermeasure development.

  12. Lactate and force production in skeletal muscle.

    PubMed

    Kristensen, Michael; Albertsen, Janni; Rentsch, Maria; Juel, Carsten

    2005-01-15

    Lactic acid accumulation is generally believed to be involved in muscle fatigue. However, one study reported that in rat soleus muscle (in vitro), with force depressed by high external K(+) concentrations a subsequent incubation with lactic acid restores force and thereby protects against fatigue. However, incubation with 20 mm lactic acid reduces the pH gradient across the sarcolemma, whereas the gradient is increased during muscle activity. Furthermore, unlike active muscle the Na(+)-K(+) pump is not activated. We therefore hypothesized that lactic acid does not protect against fatigue in active muscle. Three incubation solutions were used: 20 mM Na-lactate (which acidifies internal pH), 12 mM Na-lactate +8 mm lactic acid (which mimics the pH changes during muscle activity), and 20 mM lactic acid (which acidifies external pH more than internal pH). All three solutions improved force in K(+)-depressed rat soleus muscle. The pH regulation associated with lactate incubation accelerated the Na(+)-K(+) pump. To study whether the protective effect of lactate/lactic acid is a general mechanism, we stimulated muscles to fatigue with and without pre-incubation. None of the incubation solutions improved force development in repetitively stimulated muscle (Na-lactate had a negative effect). It is concluded that although lactate/lactic acid incubation regains force in K(+)-depressed resting muscle, a similar incubation has no or a negative effect on force development in active muscle. It is suggested that the difference between the two situations is that lactate/lactic acid removes the negative consequences of an unusual large depolarization in the K(+)-treated passive muscle, whereas the depolarization is less pronounced in active muscle.

  13. Synchronous monitoring of muscle dynamics and electromyogram

    NASA Astrophysics Data System (ADS)

    Zakir Hossain, M.; Grill, Wolfgang

    2011-04-01

    A non-intrusive novel detection scheme has been implemented to detect the lateral muscle extension, force of the skeletal muscle and the motor action potential (EMG) synchronously. This allows the comparison of muscle dynamics and EMG signals as a basis for modeling and further studies to determine which architectural parameters are most sensitive to changes in muscle activity. For this purpose the transmission time for ultrasonic chirp signal in the frequency range of 100 kHz to 2.5 MHz passing through the muscle under observation and respective motor action potentials are recorded synchronously to monitor and quantify biomechanical parameters related to muscle performance. Additionally an ultrasonic force sensor has been employed for monitoring. Ultrasonic traducers are placed on the skin to monitor muscle expansion. Surface electrodes are placed suitably to pick up the potential for activation of the monitored muscle. Isometric contraction of the monitored muscle is ensured by restricting the joint motion with the ultrasonic force sensor. Synchronous monitoring was initiated by a software activated audio beep starting at zero time of the subsequent data acquisition interval. Computer controlled electronics are used to generate and detect the ultrasonic signals and monitor the EMG signals. Custom developed software and data analysis is employed to analyze and quantify the monitored data. Reaction time, nerve conduction speed, latent period between the on-set of EMG signals and muscle response, degree of muscle activation and muscle fatigue development, rate of energy expenditure and motor neuron recruitment rate in isometric contraction, and other relevant parameters relating to muscle performance have been quantified with high spatial and temporal resolution.

  14. Quantitative Muscle Ultrasonography in Carpal Tunnel Syndrome

    PubMed Central

    2016-01-01

    Objective To assess the reliability of quantitative muscle ultrasonography (US) in healthy subjects and to evaluate the correlation between quantitative muscle US findings and electrodiagnostic study results in patients with carpal tunnel syndrome (CTS). The clinical significance of quantitative muscle US in CTS was also assessed. Methods Twenty patients with CTS and 20 age-matched healthy volunteers were recruited. All control and CTS subjects underwent a bilateral median and ulnar nerve conduction study (NCS) and quantitative muscle US. Transverse US images of the abductor pollicis brevis (APB) and abductor digiti minimi (ADM) were obtained to measure muscle cross-sectional area (CSA), thickness, and echo intensity (EI). EI was determined using computer-assisted, grayscale analysis. Inter-rater and intra-rater reliability for quantitative muscle US in control subjects, and differences in muscle thickness, CSA, and EI between the CTS patient and control groups were analyzed. Relationships between quantitative US parameters and electrodiagnostic study results were evaluated. Results Quantitative muscle US had high inter-rater and intra-rater reliability in the control group. Muscle thickness and CSA were significantly decreased, and EI was significantly increased in the APB of the CTS group (all p<0.05). EI demonstrated a significant positive correlation with latency of the median motor and sensory NCS in CTS patients (p<0.05). Conclusion These findings suggest that quantitative muscle US parameters may be useful for detecting muscle changes in CTS. Further study involving patients with other neuromuscular diseases is needed to evaluate peripheral muscle change using quantitative muscle US. PMID:28119835

  15. Inspiratory muscle training attenuates the human respiratory muscle metaboreflex

    PubMed Central

    Witt, Jonathan D; Guenette, Jordan A; Rupert, Jim L; McKenzie, Donald C; Sheel, A William

    2007-01-01

    We hypothesized that inspiratory muscle training (IMT) would attenuate the sympathetically mediated heart rate (HR) and mean arterial pressure (MAP) increases normally observed during fatiguing inspiratory muscle work. An experimental group (Exp, n = 8) performed IMT 6 days per week for 5 weeks at 50% of maximal inspiratory pressure (MIP), while a control group (Sham, n = 8) performed IMT at 10% MIP. Pre- and post-training, subjects underwent a eucapnic resistive breathing task (RBT) (breathing frequency = 15 breaths min−1, duty cycle = 0.70) while HR and MAP were continuously monitored. Following IMT, MIP increased significantly (P < 0.05) in the Exp group (−125 ± 10 to −146 ± 12 cmH2O; mean ±s.e.m.) but not in the Sham group (−141 ± 11 to −148 ± 11 cmH2O). Prior to IMT, the RBT resulted in significant increases in HR (Sham: 59 ± 2 to 83 ± 4 beats min−1; Exp: 62 ± 3 to 83 ± 4 beats min−1) and MAP (Sham: 88 ± 2 to 106 ± 3 mmHg; Exp: 84 ± 1 to 99 ± 3 mmHg) in both groups relative to rest. Following IMT, the Sham group observed similar HR and MAP responses to the RBT while the Exp group failed to increase HR and MAP to the same extent as before (HR: 59 ± 3 to 74 ± 2 beats min−1; MAP: 84 ± 1 to 89 ± 2 mmHg). This attenuated cardiovascular response suggests a blunted sympatho-excitation to resistive inspiratory work. We attribute our findings to a reduced activity of chemosensitive afferents within the inspiratory muscles and may provide a mechanism for some of the whole-body exercise endurance improvements associated with IMT. PMID:17855758

  16. The emergence of Pax7-expressing muscle stem cells during vertebrate head muscle development

    PubMed Central

    Nogueira, Julia Meireles; Hawrot, Katarzyna; Sharpe, Colin; Noble, Anna; Wood, William M.; Jorge, Erika C.; Goldhamer, David J.; Kardon, Gabrielle; Dietrich, Susanne

    2015-01-01

    Pax7 expressing muscle stem cells accompany all skeletal muscles in the body and in healthy individuals, efficiently repair muscle after injury. Currently, the in vitro manipulation and culture of these cells is still in its infancy, yet muscle stem cells may be the most promising route toward the therapy of muscle diseases such as muscular dystrophies. It is often overlooked that muscular dystrophies affect head and body skeletal muscle differently. Moreover, these muscles develop differently. Specifically, head muscle and its stem cells develop from the non-somitic head mesoderm which also has cardiac competence. To which extent head muscle stem cells retain properties of the early head mesoderm and might even be able to switch between a skeletal muscle and cardiac fate is not known. This is due to the fact that the timing and mechanisms underlying head muscle stem cell development are still obscure. Consequently, it is not clear at which time point one should compare the properties of head mesodermal cells and head muscle stem cells. To shed light on this, we traced the emergence of head muscle stem cells in the key vertebrate models for myogenesis, chicken, mouse, frog and zebrafish, using Pax7 as key marker. Our study reveals a common theme of head muscle stem cell development that is quite different from the trunk. Unlike trunk muscle stem cells, head muscle stem cells do not have a previous history of Pax7 expression, instead Pax7 expression emerges de-novo. The cells develop late, and well after the head mesoderm has committed to myogenesis. We propose that this unique mechanism of muscle stem cell development is a legacy of the evolutionary history of the chordate head mesoderm. PMID:26042028

  17. Three Intermittent Sessions of Cryotherapy Reduce the Secondary Muscle Injury in Skeletal Muscle of Rat

    PubMed Central

    Oliveira, Nuno M. L.; Rainero, Elaine P.; Salvini, Tania F.

    2006-01-01

    Although cryotherapy associated to compression is recommended as immediate treatment after muscle injury, the effect of intermittent sessions of these procedures in the area of secondary muscle injury is not established. This study examined the effect of three sessions of cryotherapy (30 min of ice pack each 2h) and muscle compression (sand pack) in the muscle-injured area. Twenty-four Wistar rats (312 ± 20g) were evaluated. In three groups, the middle belly of tibialis anterior (TA) muscle was injured by a frozen iron bar and received one of the following treatments: a) three sessions of cryotherapy; b) three sessions of compression; c) not treated. An uninjured group received sessions of cryotherapy. Frozen muscles were cross- sectioned (10 µm) and stained for the measurement of injured and uninjured muscle area. Injured muscles submitted to cryotherapy showed the smallest injured area (29.83 ± 6.6%), compared to compressed (39.2 ± 2.8%, p= 0.003) and untreated muscles (41.74 ± 4.0%, p = 0.0008). No difference was found between injured compressed and injured untreated muscles. In conclusion, three intermittent sessions of cryotherapy applied immediately after muscle damage was able to reduce the secondary muscle injury, while only the muscle compression did not provide the same effectiveness. Key Points Three sessions of cryotherapy (30 min each 2 hours) applied immediately after muscle damage reduce the secondary muscle injury. Sessions of compression applied after muscle damage are not able to reduce the secondary muscle injury. PMID:24259995

  18. An analysis on muscle tone of lower limb muscles on flexible flat foot.

    PubMed

    Um, Gi-Mai; Wang, Joong-San; Park, Si-Eun

    2015-10-01

    [Purpose] The aim of this study was to examine differences in the muscle tone and stiffness of leg muscles according to types of flexible flat foot. [Subjects and Methods] For 30 subjects 10 in a normal foot group (NFG), 10 in group with both flexible flat feet (BFFG), and 10 in a group with flexible flat feet on one side (OFFG), myotonometry was used to measure the muscle tone and stiffness of the tibialis anterior muscle (TA), the rectus femoris muscle (RF), the medial gastrocnemius (MG), and the long head of the biceps femoris muscle (BF) of both lower extremities. [Results] In the measurement results, only the stiffness of TA and MG of the NFG and the BFFG showed significant differences. The muscle tone and stiffness were highest in the BFFG, followed by the OFFG and NFG, although the difference was insignificant. In the case of the OFFG, there was no significant difference in muscle tone and stiffness compared to that in the NGF and the BFFG. Furthermore, in the NFG, the non-dominant leg showed greater muscle tone and stiffness than the dominant leg, although the difference was insignificant. [Conclusion] During the relax condition, the flexible flat foot generally showed a greater muscle tone and stiffness of both lower extremities compared to the normal foot. The stiffness was particularly higher in the TA and MG muscles. Therefore, the muscle tone and stiffness of the lower extremity muscles must be considered in the treatment of flat foot.

  19. Myogenic capacity of muscle progenitor cells from head and limb muscles.

    PubMed

    Grefte, Sander; Kuijpers, Mette A R; Kuijpers-Jagtman, Anne M; Torensma, Ruurd; Von den Hoff, Johannes W

    2012-02-01

    The restoration of muscles in the soft palate of patients with cleft lip and/or palate is accompanied by fibrosis, which leads to speech and feeding problems. Treatment strategies that improve muscle regeneration have only been tested in limb muscles. Therefore, in the present study the myogenic potential of muscle progenitor cells (MPCs) isolated from head muscles was compared with that of limb muscles. Muscle progenitor cells were isolated from the head muscles and limb muscles of rats and cultured. The proliferation of MPCs was analysed by DNA quantification. The differentiation capacity was analysed by quantifying the numbers of fused cells, and by measuring the mRNA levels of differentiation markers. Muscle progenitor cells were stained to quantify the expression of paired box protein Pax 7 (Pax-7), myoblast determination protein 1 (MyoD), and myogenin. Proliferation was similar in the head MPCs and the limb MPCs. Differentiating head and limb MPCs showed a comparable number of fused cells and mRNA expression levels of myosin-1 (Myh1), myosin-3 (Myh3), and myosin-4 (Myh4). During proliferation and differentiation, the number of Pax-7(+), MyoD(+), and myogenin(+) cells in head and limb MPCs was equal. It was concluded that head and limb MPCs show similar myogenic capacities in vitro. Therefore, in vivo myogenic differences between those muscles might rely on the local microenvironment. Thus, regenerative strategies for limb muscles might also be used for head muscles.

  20. Impairment of muscle force transmission in spastic-paretic muscles of stroke survivors.

    PubMed

    Xiaogang Hu; Afsharipour, Babak; Rymer, William Zev; Suresh, Nina L

    2016-08-01

    Hemispheric stroke survivors tend to have persistent motor impairments, with muscle weakness and muscle spasticity observed concurrently in the affected muscles. The objective of this preliminary study was to identify whether impairment of muscle force transmission could contribute to weakness in spastic-paretic muscles of chronic stroke survivors. To characterize the efficiency of the transmission of muscle forces to the tendon, we activated biceps brachii muscle electrically by stimulating the musculocutaneous nerve with maximum current. The ratio between the elicited maximum twitch force amplitude and the maximum M-wave peak-peak amplitude was calculated as a measure of the efficiency of force transmission. Based on the preliminary results of two stroke survivors, we show that the Force/M-wave ratio was reduced in the affected biceps brachii muscles in comparison with the contralateral muscles, indicating a potential impairment in the muscle force transmission in the affected muscles. Our findings suggest that disrupted muscle force transmission to the tendon could contribute to weakness in spastic muscles of chronic stroke survivors.

  1. A decline in PABPN1 induces progressive muscle weakness in oculopharyngeal muscle dystrophy and in muscle aging.

    PubMed

    Anvar, Seyed Yahya; Raz, Yotam; Verway, Nisha; van der Sluijs, Barbara; Venema, Andrea; Goeman, Jelle J; Vissing, John; van der Maarel, Silvère M; 't Hoen, Peter A C; van Engelen, Baziel G M; Raz, Vered

    2013-06-01

    Oculopharyngeal muscular dystrophy (OPMD) is caused by trinucleotide repeat expansion mutations in Poly(A) binding protein 1 (PABPN1). PABPN1 is a regulator of mRNA stability and is ubiquitously expressed. Here we investigated how symptoms in OPMD initiate only at midlife and why a subset of skeletal muscles is predominantly affected. Genome-wide RNA expression profiles from Vastus lateralis muscles human carriers of expanded-PABPN1 at pre-symptomatic and symptomatic stages were compared with healthy controls. Major expression changes were found to be associated with age rather than with expression of expanded-PABPN1, instead transcriptomes of OPMD and elderly muscles were significantly similar (P<0.05). Using k-means clustering we identified age-dependent trends in both OPMD and controls, but trends were often accelerated in OPMD. We report an age-regulated decline in PABPN1 levels in Vastus lateralis muscles from the fifth decade. In concurrence with severe muscle degeneration in OPMD, the decline in PABPN1 accelerated in OPMD and was specific to skeletal muscles. Reduced PABPN1 levels (30% to 60%) in muscle cells induced myogenic defects and morphological signatures of cellular aging in proportion to PABPN1 expression levels. We suggest that PABPN1 levels regulate muscle cell aging and OPMD represents an accelerated muscle aging disorder.

  2. Neural control of muscle relaxation in echinoderms.

    PubMed

    Elphick, M R; Melarange, R

    2001-03-01

    Smooth muscle relaxation in vertebrates is regulated by a variety of neuronal signalling molecules, including neuropeptides and nitric oxide (NO). The physiology of muscle relaxation in echinoderms is of particular interest because these animals are evolutionarily more closely related to the vertebrates than to the majority of invertebrate phyla. However, whilst in vertebrates there is a clear structural and functional distinction between visceral smooth muscle and skeletal striated muscle, this does not apply to echinoderms, in which the majority of muscles, whether associated with the body wall skeleton and its appendages or with visceral organs, are made up of non-striated fibres. The mechanisms by which the nervous system controls muscle relaxation in echinoderms were, until recently, unknown. Using the cardiac stomach of the starfish Asterias rubens as a model, it has been established that the NO-cGMP signalling pathway mediates relaxation. NO also causes relaxation of sea urchin tube feet, and NO may therefore function as a 'universal' muscle relaxant in echinoderms. The first neuropeptides to be identified in echinoderms were two related peptides isolated from Asterias rubens known as SALMFamide-1 (S1) and SALMFamide-2 (S2). Both S1 and S2 cause relaxation of the starfish cardiac stomach, but with S2 being approximately ten times more potent than S1. SALMFamide neuropeptides have also been isolated from sea cucumbers, in which they cause relaxation of both gut and body wall muscle. Therefore, like NO, SALMFamides may also function as 'universal' muscle relaxants in echinoderms. The mechanisms by which SALMFamides cause relaxation of echinoderm muscle are not known, but several candidate signal transduction pathways are discussed here. The SALMFamides do not, however, appear to act by promoting release of NO, and muscle relaxation in echinoderms is therefore probably regulated by at least two neuronal signalling systems acting in parallel. Recently, other

  3. Signaling pathways controlling skeletal muscle mass.

    PubMed

    Egerman, Marc A; Glass, David J

    2014-01-01

    The molecular mechanisms underlying skeletal muscle maintenance involve interplay between multiple signaling pathways. Under normal physiological conditions, a network of interconnected signals serves to control and coordinate hypertrophic and atrophic messages, culminating in a delicate balance between muscle protein synthesis and proteolysis. Loss of skeletal muscle mass, termed "atrophy", is a diagnostic feature of cachexia seen in settings of cancer, heart disease, chronic obstructive pulmonary disease, kidney disease, and burns. Cachexia increases the likelihood of death from these already serious diseases. Recent studies have further defined the pathways leading to gain and loss of skeletal muscle as well as the signaling events that induce differentiation and post-injury regeneration, which are also essential for the maintenance of skeletal muscle mass. In this review, we summarize and discuss the relevant recent literature demonstrating these previously undiscovered mediators governing anabolism and catabolism of skeletal muscle.

  4. BMPs and the muscle-bone connection.

    PubMed

    Sartori, Roberta; Sandri, Marco

    2015-11-01

    Muscle and bone are two intimately connected tissues. A coordinated interplay between these tissues at mechanical levels is required for their development, function and ageing. Evidence is emerging that several genes and molecular pathways exert a pleiotropic effect on both muscle and bone. Bone morphogenetic proteins (BMPs) are secreted signal factors belonging to the transforming growth factor β (TGFβ) superfamily. BMPs have an essential role during bone and cartilage formation and maintenance. Recently, we and others have demonstrated that the BMP pathway also has a role in controlling adult skeletal muscle mass. Thus, BMPs become crucial regulators of both bone and muscle formation and homeostasis. In this review we will discuss the signalling downstream BMP and its role in muscle-bone interaction. This article is part of a Special Issue entitled "Muscle Bone Interactions".

  5. Sympathetic innervation of human muscle spindles

    PubMed Central

    Radovanovic, Dina; Peikert, Kevin; Lindström, Mona; Domellöf, Fatima Pedrosa

    2015-01-01

    The aim of the present study was to investigate the presence of sympathetic innervation in human muscle spindles, using antibodies against neuropeptide Y (NPY), NPY receptors and tyrosine hydroxylase (TH). A total of 232 muscle spindles were immunohistochemically examined. NPY and NPY receptors were found on the intrafusal fibers, on the blood vessels supplying muscle spindles and on free nerve endings in the periaxial space. TH-immunoreactivity was present mainly in the spindle nerve and vessel. This is, to our knowledge, the first morphological study concerning the sympathetic innervation of the human muscle spindles. The results provide anatomical evidence for direct sympathetic innervation of the intrafusal fibers and show that sympathetic innervation is not restricted to the blood vessels supplying spindles. Knowledge about direct sympathetic innervation of the muscle spindle might expand our understanding of motor and proprioceptive dysfunction under stress conditions, for example, chronic muscle pain syndromes. PMID:25994126

  6. Sympathetic innervation of human muscle spindles.

    PubMed

    Radovanovic, Dina; Peikert, Kevin; Lindström, Mona; Domellöf, Fatima Pedrosa

    2015-06-01

    The aim of the present study was to investigate the presence of sympathetic innervation in human muscle spindles, using antibodies against neuropeptide Y (NPY), NPY receptors and tyrosine hydroxylase (TH). A total of 232 muscle spindles were immunohistochemically examined. NPY and NPY receptors were found on the intrafusal fibers, on the blood vessels supplying muscle spindles and on free nerve endings in the periaxial space. TH-immunoreactivity was present mainly in the spindle nerve and vessel. This is, to our knowledge, the first morphological study concerning the sympathetic innervation of the human muscle spindles. The results provide anatomical evidence for direct sympathetic innervation of the intrafusal fibers and show that sympathetic innervation is not restricted to the blood vessels supplying spindles. Knowledge about direct sympathetic innervation of the muscle spindle might expand our understanding of motor and proprioceptive dysfunction under stress conditions, for example, chronic muscle pain syndromes.

  7. Muscle biopsy findings in inflammatory myopathies.

    PubMed

    Dalakas, Marinos C

    2002-11-01

    The inflammatory myopathies encompass a heterogeneous group of acquired muscle diseases characterized clinically, by muscle weakness, and histologically, by inflammatory infiltrates within the skeletal muscles. The group of these myopathies comprise three major and discrete subsets: polymyositis (PM), dermatomyositis (DM), and inclusion body myositis (IBM). Each subset retains its characteristic clinical, immunopathologic, and morphologic features regardless of whether it occurs separately or in connection with other systemic diseases. Although the diagnosis of these disorders is based on the combination of clinical examination, electromyographic data, serum muscle enzyme levels, various autoantibodies, and the muscle biopsy findings, the muscle biopsy offers the most definitive diagnostic information in the majority of the cases. This article summarizes the main histologic features that characterize PM, DM, or IBM and emphasizes the main pitfalls associated with interpretation of the biopsies.

  8. Study of photon migration in skeletal muscle

    NASA Astrophysics Data System (ADS)

    Ranasinghesagara, J.; Yao, G.

    2007-09-01

    A clear understanding of how light propagation in muscle is important for developing optical methods for muscle characterization. We investigated photon migration in muscle by imaging the optical reflectance from fresh prerigor skeletal muscles. We found the acquired reflectance patterns can not be described using existing theories. In order to quantify the equi-intensity contours of acquired reflectance images, we developed a numerical fitting function. Using this model, we studied the changes of reflectance profile during stretching and rigor process. The observed unique anisotropic features diminished after rigor completion. These results suggested that muscle sarcomere structures played important roles in modulating light propagation in whole muscle. To explain the observed patterns, we incorporated the sarcomere diffraction in a Monte Carlo model and we showed that the resulting reflectance profiles quantitatively resembled the experimental observation.

  9. [Molecular mechanisms of skeletal muscle hypertrophy].

    PubMed

    Astratenkova, I V; Rogozkin, V A

    2014-06-01

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

  10. Signaling pathways controlling skeletal muscle mass

    PubMed Central

    Egerman, Marc A.

    2014-01-01

    The molecular mechanisms underlying skeletal muscle maintenance involve interplay between multiple signaling pathways. Under normal physiological conditions, a network of interconnected signals serves to control and coordinate hypertrophic and atrophic messages, culminating in a delicate balance between muscle protein synthesis and proteolysis. Loss of skeletal muscle mass, termed “atrophy”, is a diagnostic feature of cachexia seen in settings of cancer, heart disease, chronic obstructive pulmonary disease, kidney disease, and burns. Cachexia increases the likelihood of death from these already serious diseases. Recent studies have further defined the pathways leading to gain and loss of skeletal muscle as well as the signaling events that induce differentiation and post-injury regeneration, which are also essential for the maintenance of skeletal muscle mass. In this review, we summarize and discuss the relevant recent literature demonstrating these previously undiscovered mediators governing anabolism and catabolism of skeletal muscle. PMID:24237131

  11. The transduction properties of intercostal muscle mechanoreceptors

    PubMed Central

    Holt, Gregory A; Johnson, Richard D; Davenport, Paul W

    2002-01-01

    Background Intercostal muscles are richly innervated by mechanoreceptors. In vivo studies of cat intercostal muscle have shown that there are 3 populations of intercostal muscle mechanoreceptors: primary muscle spindles (1°), secondary muscle spindles (2°) and Golgi tendon organs (GTO). The purpose of this study was to determine the mechanical transduction properties of intercostal muscle mechanoreceptors in response to controlled length and velocity displacements of the intercostal space. Mechanoreceptors, recorded from dorsal root fibers, were localized within an isolated intercostal muscle space (ICS). Changes in ICS displacement and the velocity of ICS displacement were independently controlled with an electromagnetic motor. ICS velocity (0.5 – 100 μm/msec to a displacement of 2,000 μm) and displacement (50–2,000 μm at a constant velocity of 10 μm/msec) parameters encompassed the full range of rib motion. Results Both 1° and 2° muscle spindles were found evenly distributed within the ICS. GTOs were localized along the rib borders. The 1° spindles had the greatest discharge frequency in response to displacement amplitude followed by the 2° afferents and GTOs. The 1° muscle spindles also possessed the greatest discharge frequency in response to graded velocity changes, 3.0 spikes·sec-1/μm·msec-1. GTOs had a velocity response of 2.4 spikes·sec-1/μm·msec-1 followed by 2° muscle spindles at 0.6 spikes·sec-1/μm·msec-1. Conclusion The results of this study provide a systematic description of the mechanosenitivity of the 3 types of intercostal muscle mechanoreceptors. These mechanoreceptors have discharge properties that transduce the magnitude and velocity of intercostal muscle length. PMID:12392601

  12. A Depolarizing Electrogenic Pump in Frog Muscle

    DTIC Science & Technology

    1975-08-01

    mw copy AFRRI SR75-20 AUGUST 1975 AFRRI SCIENTIFIC REPORT O ■ to A DEPOLARIZING ELECTROGENIC PUMP IN FROG MUSCLE D. Geduldig D. R...Academy of Sciences - National Research Council. AFRRI SR75-20 August 1975 A DEPOLARIZING ELECTROGENIC PUMP IN FROG MUSCLE D. GEDULDIG* D. R...INTRODUCTION When Na-enriched frog muscles are bathed in Na- and K-free saline, the small amount of potassium which could accumulate outside of the membrane

  13. Female orgasm: role of pubococcygeus muscle.

    PubMed

    Graber, B; Kline-Graber, G

    1979-08-01

    An examination is made of the role of the pubococcygeus muscle in relation to female orgasm in 281 women. A statistically significant difference is reported between orgasmic and anorgasmic women and the physiological state of the pubococcygeus muscle as measured using a pressure sensitive device inserted in the vagina. These data suggest the pubococcygeus muscle plays an important part in the pathophysiology of female orgasm.

  14. Denervation and reinnervation of skeletal muscle

    NASA Technical Reports Server (NTRS)

    Mayer, R. F.; Max, S. R.

    1983-01-01

    A review is presented of the physiological and biochemical changes that occur in mammalian skeletal muscle after denervation and reinnervation. These changes are compared with those observed after altered motor function. Also considered is the nature of the trophic influence by which nerves control muscle properties. Topics examined include the membrane and contractile properties of denervated and reinnervated muscle; the cholinergic proteins, such as choline acetyltransferase, acetylcholinesterase, and the acetylcholine receptor; and glucose-6-phosphate dehydrogenase.

  15. The Smooth Muscle of the Artery

    DTIC Science & Technology

    1975-01-01

    to keep up with inter- national standards. The German Cancer Research Center as well as the Hax-Planck Inntitutes of Heidelberg are well equipped to...SOMLYO: I plan to briefly review some of the aspects of normal function of vascular smooth muscle with particular ---- I SMOOTH MUSCLE STRUCTURE 35...schematic review of the data on catabolism in connective tissue cells smooth muscle cells. The increasing number of electron microscopic studies of

  16. Myoglobin Function in Exercising Skeletal Muscle

    NASA Astrophysics Data System (ADS)

    Cole, Randolph P.

    1982-04-01

    Short-term perfusion of the isolated dog gastrocnemius-plantaris muscle with hydrogen peroxide resulted in a decrease in steady-state muscle oxygen consumption and isometric tension generation. Hydrogen peroxide converted intracellular myoglobin to products incapable of combination with oxygen, but had no deleterious effect on neuromuscular transmission or on mitochondrial oxidative phosphorylation. It is concluded that functional intracellular myoglobin is important in maintaining oxygen consumption and tension generation in exercising skeletal muscle.

  17. Insulin binding to individual rat skeletal muscles

    SciTech Connect

    Koerker, D.J.; Sweet, I.R.; Baskin, D.G. )

    1990-10-01

    Studies of insulin binding to skeletal muscle, performed using sarcolemmal membrane preparations or whole muscle incubations of mixed muscle or typical red (soleus, psoas) or white (extensor digitorum longus (EDL), gastrocnemius) muscle, have suggested that red muscle binds more insulin than white muscle. We have evaluated this hypothesis using cryostat sections of unfixed tissue to measure insulin binding in a broad range of skeletal muscles; many were of similar fiber-type profiles. Insulin binding per square millimeter of skeletal muscle slice was measured by autoradiography and computer-assisted densitometry. We found a 4.5-fold range in specific insulin tracer binding, with heart and predominantly slow-twitch oxidative muscles (SO) at the high end and the predominantly fast-twitch glycolytic (FG) muscles at the low end of the range. This pattern reflects insulin sensitivity. Evaluation of displacement curves for insulin binding yielded linear Scatchard plots. The dissociation constants varied over a ninefold range (0.26-2.06 nM). Binding capacity varied from 12.2 to 82.7 fmol/mm2. Neither binding parameter was correlated with fiber type or insulin sensitivity; e.g., among three muscles of similar fiber-type profile, the EDL had high numbers of low-affinity binding sites, whereas the quadriceps had low numbers of high-affinity sites. In summary, considerable heterogeneity in insulin binding was found among hindlimb muscles of the rat, which can be attributed to heterogeneity in binding affinities and the numbers of binding sites. It can be concluded that a given fiber type is not uniquely associated with a set of insulin binding parameters that result in high or low binding.

  18. Asymmetric deformation of contracting human gastrocnemius muscle.

    PubMed

    Kinugasa, Ryuta; Hodgson, John A; Edgerton, V Reggie; Sinha, Shantanu

    2012-02-01

    Muscle fiber deformation is related to its cellular structure, as well as its architectural arrangement within the musculoskeletal system. While playing an important role in aponeurosis displacement, and efficiency of force transmission to the tendon, such deformation also provides important clues about the underlying mechanical structure of the muscle. We hypothesized that muscle fiber cross section would deform asymmetrically to satisfy the observed constant volume of muscle during a contraction. Velocity-encoded, phase-contrast, and morphological magnetic resonance imaging techniques were used to measure changes in fascicle length, pinnation angle, and aponeurosis separation of the human gastrocnemius muscle during passive and active eccentric ankle joint movements. These parameters were then used to subsequently calculate the in-plane muscle area subtended by the two aponeuroses and fascicles and to calculate the in-plane (dividing area by fascicle length), and through-plane (dividing muscle volume by area) thicknesses. Constant-volume considerations of the whole-muscle geometry require that, as fascicle length increases, the muscle fiber cross-sectional area must decrease in proportion to the length change. Our empirical findings confirm the definition of a constant-volume rule that dictates that changes in the dimension perpendicular to the plane, i.e., through-plane thickness, (-6.0% for passive, -3.3% for eccentric) equate to the reciprocal of the changes in area (6.8% for passive, 3.7% for eccentric) for both exercise paradigms. The asymmetry in fascicle cross-section deformation for both passive and active muscle fibers is established in this study with a ∼22% in-plane and ∼6% through-plane fascicle thickness change. These fiber deformations have functional relevance, not only because they affect the force production of the muscle itself, but also because they affect the characteristics of adjacent muscles by deflecting their line of pull.

  19. Direct optical activation of skeletal muscle fibres efficiently controls muscle contraction and attenuates denervation atrophy.

    PubMed

    Magown, Philippe; Shettar, Basavaraj; Zhang, Ying; Rafuse, Victor F

    2015-10-13

    Neural prostheses can restore meaningful function to paralysed muscles by electrically stimulating innervating motor axons, but fail when muscles are completely denervated, as seen in amyotrophic lateral sclerosis, or after a peripheral nerve or spinal cord injury. Here we show that channelrhodopsin-2 is expressed within the sarcolemma and T-tubules of skeletal muscle fibres in transgenic mice. This expression pattern allows for optical control of muscle contraction with comparable forces to nerve stimulation. Force can be controlled by varying light pulse intensity, duration or frequency. Light-stimulated muscle fibres depolarize proportionally to light intensity and duration. Denervated triceps surae muscles transcutaneously stimulated optically on a daily basis for 10 days show a significant attenuation in atrophy resulting in significantly greater contractile forces compared with chronically denervated muscles. Together, this study shows that channelrhodopsin-2/H134R can be used to restore function to permanently denervated muscles and reduce pathophysiological changes associated with denervation pathologies.

  20. Surface electromyogram and muscle ultrasonography for detection of muscle fasciculations in pediatric peripheral neuropathy.

    PubMed

    Oguri, Masayoshi; Saito, Yoshiaki; Okazaki, Tetsuya; Matsumura, Wataru; Ohno, Koyo; Togawa, Masami; Fukuda, Chisako; Saito, Yuko; Nishino, Ichizo; Maegaki, Yoshihiro

    2017-03-16

    A 12-year-old girl presented with talipes equinus of both legs, attenuation of upper and lower limb tendon reflexes, thermal hyperalgesia, and reduction of vibratory sensation. On clinical examination, muscle twitches of fingers of both hands, as well as the abductor halluces and the dorsal interossei muscles of the right foot were observed. Nerve conduction velocity was significantly declined in the upper and lower extremities. Needle electromyography (EMG) was not performed; however, ultrasonography revealed repetitive, semi-regular muscle twitches lasting 0.2-0.4s, concomitant with muscle discharges on surface EMG in the right foot muscles. These findings were compatible with contraction fasciculation in muscles under chronic reinnervation. Nerve and muscle biopsies were suggestive of chronic motor, sensory, and autonomic neuropathy. This is the first case of pediatric peripheral neuropathy where muscle fasciculation was noninvasively identified by simultaneous surface EMG and ultrasonography.

  1. Determinants of muscle and bone aging

    PubMed Central

    Curtis, E; Litwic, A; Cooper, C; Dennison, E

    2015-01-01

    Loss of bone and muscle with advancing age represent a huge threat to loss of independence in later life. Osteoporosis represents a major public health problem through its association with fragility fractures, primarily of the hip, spine and distal forearm. Sarcopenia, the age related loss of muscle mass and function, may add to fracture risk by increasing falls risk. In the context of muscle aging, it is important to remember that it is not just a decline in muscle mass which contributes to the deterioration of muscle function. Other factors underpinning muscle quality come into play, including muscle composition, aerobic capacity and metabolism, fatty infiltration, insulin resistance, fibrosis and neural activation. Genetic, developmental, endocrine and lifestyle factors, such as physical activity, smoking and poor diet have dual effects on both muscle and bone mass in later life and these will be reviewed here. These include poor nutrition, lack of physical activity and cigarette smoking, comorbidities or medication use. Recent work has highlighted a possible role for the early environment. Inflammaging is an exciting emerging research field that is likely to prove relevant to future work, including interventions designed to retard to reverse bone and muscle loss with age. PMID:25820482

  2. Mechanisms of myoblast fusion during muscle development

    PubMed Central

    Kim, Ji Hoon; Jin, Peng; Duan, Rui; Chen, Elizabeth H.

    2015-01-01

    The development and regeneration of skeletal muscles require the fusion of mononulceated muscle cells to form multinucleated, contractile muscle fibers. Studies using a simple genetic model, Drosophila melanogaster, have discovered many evolutionarily conserved fusion-promoting factors in vivo. Recent work in zebrafish and mouse also identified several vertebrate-specific factors required for myoblast fusion. Here, we integrate progress in multiple in vivo systems and highlight conceptual advance in understanding how muscle cell membranes are brought together for fusion. We focus on the molecular machinery at the fusogenic synapse and present a three-step model to describe the molecular and cellular events leading to fusion pore formation. PMID:25989064

  3. Leiomodin and tropomodulin in smooth muscle

    NASA Technical Reports Server (NTRS)

    Conley, C. A.

    2001-01-01

    Evidence is accumulating to suggest that actin filament remodeling is critical for smooth muscle contraction, which implicates actin filament ends as important sites for regulation of contraction. Tropomodulin (Tmod) and smooth muscle leiomodin (SM-Lmod) have been found in many tissues containing smooth muscle by protein immunoblot and immunofluorescence microscopy. Both proteins cofractionate with tropomyosin in the Triton-insoluble cytoskeleton of rabbit stomach smooth muscle and are solubilized by high salt. SM-Lmod binds muscle tropomyosin, a biochemical activity characteristic of Tmod proteins. SM-Lmod staining is present along the length of actin filaments in rat intestinal smooth muscle, while Tmod stains in a punctate pattern distinct from that of actin filaments or the dense body marker alpha-actinin. After smooth muscle is hypercontracted by treatment with 10 mM Ca(2+), both SM-Lmod and Tmod are found near alpha-actinin at the periphery of actin-rich contraction bands. These data suggest that SM-Lmod is a novel component of the smooth muscle actin cytoskeleton and, furthermore, that the pointed ends of actin filaments in smooth muscle may be capped by Tmod in localized clusters.

  4. Artificial Muscle Kits for the Classroom

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Commonly referred to as "artificial muscles," electroactive polymer (EAP) materials are lightweight strips of highly flexible plastic that bend or stretch when subjected to electric voltage. EAP materials may prove to be a substitution for conventional actuation components such as motors and gears. Since the materials behave similarly to biological muscles, this emerging technology has the potential to develop improved prosthetics and biologically-inspired robots, and may even one day replace damaged human muscles. The practical application of artificial muscles provides a challenge, however, since the material requires improved effectiveness and durability before it can fulfill its potential.

  5. Biologic-free mechanically induced muscle regeneration

    PubMed Central

    Cezar, Christine A.; Roche, Ellen T.; Vandenburgh, Herman H.; Duda, Georg N.; Walsh, Conor J.; Mooney, David J.

    2016-01-01

    Severe skeletal muscle injuries are common and can lead to extensive fibrosis, scarring, and loss of function. Clinically, no therapeutic intervention exists that allows for a full functional restoration. As a result, both drug and cellular therapies are being widely investigated for treatment of muscle injury. Because muscle is known to respond to mechanical loading, we investigated instead whether a material system capable of massage-like compressions could promote regeneration. Magnetic actuation of biphasic ferrogel scaffolds implanted at the site of muscle injury resulted in uniform cyclic compressions that led to reduced fibrous capsule formation around the implant, as well as reduced fibrosis and inflammation in the injured muscle. In contrast, no significant effect of ferrogel actuation on muscle vascularization or perfusion was found. Strikingly, ferrogel-driven mechanical compressions led to enhanced muscle regeneration and a ∼threefold increase in maximum contractile force of the treated muscle at 2 wk compared with no-treatment controls. Although this study focuses on the repair of severely injured skeletal muscle, magnetically stimulated bioagent-free ferrogels may find broad utility in the field of regenerative medicine. PMID:26811474

  6. Conduction velocity of antigravity muscle action potentials.

    PubMed

    Christova, L; Kosarov, D; Christova, P

    1992-01-01

    The conduction velocity of the impulses along the muscle fibers is one of the parameters of the extraterritorial potentials of the motor units allowing for the evaluation of the functional state of the muscles. There are no data about the conduction velocities of antigravity muscleaction potentials. In this paper we offer a method for measuring conduction velocity of potentials of single MUs and the averaged potentials of the interference electromiogram (IEMG) lead-off by surface electrodes from mm. sternocleidomastoideus, trapezius, deltoideus (caput laterale) and vastus medialis. The measured mean values of the conduction velocity of antigravity muscles potentials can be used for testing the functional state of the muscles.

  7. Olanzapine overdose presenting with acute muscle toxicity

    PubMed Central

    Keyal, Niraj; Shrestha, Gentle Sunder; Pradhan, Saurabh; Maharjan, Ramesh; Acharya, Subhash Prasad; Marhatta, Moda Nath

    2017-01-01

    Olanzapine is an atypical antipsychotic drug that is being increasingly used as an intentional overdose. It usually presents with reduced and fluctuating level of consciousness and coma. It may rarely present with muscle toxicity by binding to HT2A receptor in skeletal muscle and increasing its permeability. We report a case of such poisoning which had no obvious symptoms but was brought to emergency due to overdose and was found to have acute muscle toxicity as evidenced by raised creatine phosphokinase (CPK) levels. From this, we also want to emphasize that CPK levels should be checked in all the patient's prescribed olanzapine to look for muscle toxicity.

  8. Bilateral four heads of the sternocleidomastoid muscle.

    PubMed

    Kim, So-Yeon; Jang, Han-Bin; Kim, Jinu; Yoon, Sang Pil

    2015-09-01

    The sternocleidomastoid muscle shows a wide range of variations including supernumerary muscular heads. We found a rare variation in the sternocleidomastoid muscle with bilateral supernumerary heads in a 67-year-old Korean male cadaver. Bilateral four muscle bellies were recorded: two sternomastoids, one cleido-occipital and one cleido-mastoid occipital on the right side, and one sternomastoid, one cleido-occipital and two cleido-mastoids on the left side. The variation of bilateral four heads on sternocleidomastoid muscle is important to surgeons and anesthetists for clinical using.

  9. Muscle Mass Predicts Outcomes Following Liver Transplantation

    PubMed Central

    DiMartini, Andrea; Cruz, Ruy J.; Dew, Mary Amanda; Myaskovsky, Larissa; Goodpaster, Bret; Fox, Kristen; Kim, Kevin H.; Fontes, Paulo

    2015-01-01

    Background and aims For patients with end-stage liver disease commonly used indices of nutritional status (i.e. body weight and BMI) are often inflated due to fluid overload (i.e. ascites, peripheral edema) resulting in an underdiagnosis of malnutrition. As muscle is the largest protein reservoir in the body, an estimate of muscle mass may be a more reliable and valid estimate of nutritional status. Methods Therefore, we used pre-transplant computerized tomography data of 338 liver transplant (LTX) candidates to identify muscle and fat mass based on a specific abdominal transverse section commonly used in body composition analyses and investigated the contribution of this measure to specific post-LTX outcomes. Results We found the majority, 68%, of our patients could be defined as cachetic. For men muscle mass predicted many important post-transplant outcomes including intensive care unit (ICU) and total length of stay and days of intubation. Muscle mass was a significant predictor of survival and also predicted disposition to home vs another facility. For women muscle mass predicted lengths of ICU and total stay and days of intubation but the effect was modest. Muscle mass did not predict survival or disposition for women. Conclusions As pre-transplant muscle mass was associated with many important post-operative outcomes we discuss these findings in the context of possible pre-transplant interventions to either improve or sustain muscle mass before surgery. PMID:23960026

  10. Rectus muscle plication using an adjustable technique

    PubMed Central

    Velez, Federico G.; Demer, Joseph L.; Pihlblad, Matthew S.; Pineles, Stacy L.

    2013-01-01

    Background Rectus muscle plication is an alternative muscle-strengthening procedure to rectus muscle resection. Possible advantages of rectus muscle plication include a lower risk of “lost” muscles and anterior segment ischemia. Methods This was a retrospective case series describing a surgical procedure for rectus muscle plication using an adjustable suture technique that can be employed on any of the four rectus muscles. Results A total of 5 adult patients underwent adjustable suture plication procedures. Of these, 2 patients required suture adjustment postoperatively. At the final follow-up visit, all of the patients maintained satisfactory ocular alignment within 6Δ of orthotropia for horizontal deviations and 2Δ of orthotropia for vertical deviations. Diplopia was eliminated in all cases with preoperative diplopia. There were no postoperative complications or unexpected shifts in ocular alignment. Conclusions Rectus muscle plication using this adjustable suture technique may serve as an alternative to rectus muscle resection and may be particularly useful in patients who are at risk for anterior segment ischemia or those in whom a shorter anesthesia time is recommended. PMID:24160967

  11. The relationship between exercise-induced muscle fatigue, arterial blood flow and muscle perfusion after 56 days local muscle unloading.

    PubMed

    Weber, Tobias; Ducos, Michel; Mulder, Edwin; Beijer, Åsa; Herrera, Frankyn; Zange, Jochen; Degens, Hans; Bloch, Wilhelm; Rittweger, Jörn

    2014-05-01

    In the light of the dynamic nature of habitual plantar flexor activity, we utilized an incremental isokinetic exercise test (IIET) to assess the work-related power deficit (WoRPD) as a measure for exercise-induced muscle fatigue before and after prolonged calf muscle unloading and in relation to arterial blood flow and muscle perfusion. Eleven male subjects (31 ± 6 years) wore the HEPHAISTOS unloading orthosis unilaterally for 56 days. It allows habitual ambulation while greatly reducing plantar flexor activity and torque production. Endpoint measurements encompassed arterial blood flow, measured in the femoral artery using Doppler ultrasound, oxygenation of the soleus muscle assessed by near-infrared spectroscopy, lactate concentrations determined in capillary blood and muscle activity using soleus muscle surface electromyography. Furthermore, soleus muscle biopsies were taken to investigate morphological muscle changes. After the intervention, maximal isokinetic torque was reduced by 23·4 ± 8·2% (P<0·001) and soleus fibre size was reduced by 8·5 ± 13% (P = 0·016). However, WoRPD remained unaffected as indicated by an unchanged loss of relative plantar flexor power between pre- and postexperiments (P = 0·88). Blood flow, tissue oxygenation, lactate concentrations and EMG median frequency kinematics during the exercise test were comparable before and after the intervention, whereas the increase of RMS in response to IIET was less following the intervention (P = 0·03). In conclusion, following submaximal isokinetic muscle work exercise-induced muscle fatigue is unaffected after prolonged local muscle unloading. The observation that arterial blood flow was maintained may underlie the unchanged fatigability.

  12. Sumoylated α-skeletal muscle actin in the skeletal muscle of adult rats.

    PubMed

    Uda, Munehiro; Kawasaki, Hiroaki; Iizumi, Kyoichi; Shigenaga, Ayako; Baba, Takeshi; Naito, Hisashi; Yoshioka, Toshitada; Yamakura, Fumiyuki

    2015-11-01

    Skeletal muscles are composed of two major muscle fiber types: slow-twitch oxidative fibers and fast-twitch glycolytic fibers. The proteins in these muscle fibers are known to differ in their expression, relative abundance, and post-translational modifications. In this study, we report a previously unreported post-translational modification of α-skeletal muscle actin in the skeletal muscles of adult male F344 rats in vivo. Using two-dimensional electrophoresis (2D-PAGE), we first examined the differences in the protein expression profiles between the soleus and plantaris muscles. We found higher intensity protein spots at approximately 60 kDa and pH 9 on 2D-PAGE for the soleus muscle compared with the plantaris muscle. These spots were identified as α-skeletal muscle actin by liquid chromatography-nanoelectrospray ionization-tandem mass spectrometry and western blot analyses. In addition, we found that the 60 kDa α-skeletal muscle actin is modified by small ubiquitin-like modifier (SUMO) 1, using 2D-PAGE and western blot analyses. Furthermore, we found that α-skeletal muscle actin with larger molecular weight was localized in the nuclear and cytosol of the skeletal muscle, but not in the myofibrillar fraction by the combination of subcellular fractionation and western blot analyses. These results suggest that α-skeletal muscle actin is modified by SUMO-1 in the skeletal muscles, localized in nuclear and cytosolic fractions, and the extent of this modification is much higher in the slow muscles than in the fast muscles. This is the first study to show the presence of SUMOylated actin in animal tissues.

  13. Muscle organizers in Drosophila: the role of persistent larval fibers in adult flight muscle development

    NASA Technical Reports Server (NTRS)

    Farrell, E. R.; Fernandes, J.; Keshishian, H.

    1996-01-01

    In many organisms muscle formation depends on specialized cells that prefigure the pattern of the musculature and serve as templates for myoblast organization and fusion. These include muscle pioneers in insects and muscle organizing cells in leech. In Drosophila, muscle founder cells have been proposed to play a similar role in organizing larval muscle development during embryogenesis. During metamorphosis in Drosophila, following histolysis of most of the larval musculature, there is a second round of myogenesis that gives rise to the adult muscles. It is not known whether muscle founder cells organize the development of these muscles. However, in the thorax specific larval muscle fibers do not histolyze at the onset of metamorphosis, but instead serve as templates for the formation of a subset of adult muscles, the dorsal longitudinal flight muscles (DLMs). Because these persistent larval muscle fibers appear to be functioning in many respects like muscle founder cells, we investigated whether they were necessary for DLM development by using a microbeam laser to ablate them singly and in combination. We found that, in the absence of the larval muscle fibers, DLMs nonetheless develop. Our results show that the persistent larval muscle fibers are not required to initiate myoblast fusion, to determine DLM identity, to locate the DLMs in the thorax, or to specify the total DLM fiber volume. However, they are required to regulate the number of DLM fibers generated. Thus, while the persistent larval muscle fibers are not obligatory for DLM fiber formation and differentiation, they are necessary to ensure the development of the correct number of fibers.

  14. Muscle MRI Findings in Childhood/Adult Onset Pompe Disease Correlate with Muscle Function

    PubMed Central

    Figueroa-Bonaparte, Sebastián; Segovia, Sonia; Llauger, Jaume; Belmonte, Izaskun; Pedrosa, Irene; Alejaldre, Aída; Mayos, Mercè; Suárez-Cuartín, Guillermo; Gallardo, Eduard; Illa, Isabel; Díaz-Manera, Jordi

    2016-01-01

    Objectives Enzyme replacement therapy has shown to be effective for childhood/adult onset Pompe disease (AOPD). The discovery of biomarkers useful for monitoring disease progression is one of the priority research topics in Pompe disease. Muscle MRI could be one possible test but the correlation between muscle MRI and muscle strength and function has been only partially addressed so far. Methods We studied 34 AOPD patients using functional scales (Manual Research Council scale, hand held myometry, 6 minutes walking test, timed to up and go test, time to climb up and down 4 steps, time to walk 10 meters and Motor Function Measure 20 Scale), respiratory tests (Forced Vital Capacity seated and lying, Maximun Inspiratory Pressure and Maximum Expiratory Pressure), daily live activities scales (Activlim) and quality of life scales (Short Form-36 and Individualized Neuromuscular Quality of Life questionnaire). We performed a whole body muscle MRI using T1w and 3-point Dixon imaging centered on thighs and lower trunk region. Results T1w whole body muscle MRI showed a homogeneous pattern of muscle involvement that could also be found in pre-symptomatic individuals. We found a strong correlation between muscle strength, muscle functional scales and the degree of muscle fatty replacement in muscle MRI analyzed using T1w and 3-point Dixon imaging studies. Moreover, muscle MRI detected mild degree of fatty replacement in paraspinal muscles in pre-symptomatic patients. Conclusion Based on our findings, we consider that muscle MRI correlates with muscle function in patients with AOPD and could be useful for diagnosis and follow-up in pre-symptomatic and symptomatic patients under treatment. Take home message Muscle MRI correlates with muscle function in patients with AOPD and could be useful to follow-up patients in daily clinic. PMID:27711114

  15. Subminiature transducers for measuring forces and deformation of heart muscle

    NASA Technical Reports Server (NTRS)

    Feldstein, C.; Osher, J. V.; Lewis, G. W.; Silver, R. H.; Duran, E. N.

    1975-01-01

    Two subminiature transducers, one measuring muscle forces and one measuring muscle displacement, can be inserted into heart muscle without interfering with it. Probe, approximately 1 mm (0.04 in), causes no damage to heart muscle. Probe can be rotated to different positions to measure muscle forces from various directions.

  16. Chronic Stimulation-Induced Changes in the Rodent Thyroarytenoid Muscle

    ERIC Educational Resources Information Center

    McMullen, Colleen A.; Butterfield, Timothy A.; Dietrich, Maria; Andreatta, Richard D.; Andrade, Francisco H.; Fry, Lisa; Stemple, Joseph C.

    2011-01-01

    Purpose: Therapies for certain voice disorders purport principles of skeletal muscle rehabilitation to increase muscle mass, strength, and endurance. However, applicability of limb muscle rehabilitation to the laryngeal muscles has not been tested. In this study, the authors examined the feasibility of the rat thyroarytenoid muscle to remodel as a…

  17. Study on contraction and relaxation of experimentally denervated and immobilized muscles: Comparison with dystrophic muscles

    NASA Technical Reports Server (NTRS)

    Takamori, M.; Tsujihata, M.; Mori, M.; Hazama, R.; Ide, Y.

    1980-01-01

    The contraction-relaxation mechanism of experimentally denervated and immobilized muscles of the rabbit is examined. Results are compared with those of human dystrophic muscles, in order to elucidate the role and extent of the neurotrophic factor, and the role played by the intrinsic activity of muscle in connection with pathogenesis and pathophysiology of this disease.

  18. Association of muscle hardness with muscle tension dynamics: a physiological property.

    PubMed

    Murayama, Mitsuyoshi; Watanabe, Kotaro; Kato, Ryoko; Uchiyama, Takanori; Yoneda, Tsugutake

    2012-01-01

    This study aimed to investigate the relationship between muscle hardness and muscle tension in terms of length-tension relationship. A frog gastrocnemius muscle sample was horizontally mounted on the base plate inside a chamber and was stretched from 100 to 150% of the pre-length, in 5% increments. After each step of muscle lengthening, electrical field stimulation for induction of tetanus was applied using platinum-plate electrodes positioned on either side of the muscle submerged in Ringer's solution. The measurement of muscle hardness, i.e., applying perpendicular distortion, was performed whilst maintaining the plateau of passive and tetanic tension. The relationship between normalised tension and normalised muscle hardness was evaluated. The length-hardness diagram could be created from the modification with the length-tension diagram. It is noteworthy that muscle hardness was proportional to passive and total tension. Regression analysis revealed a significant correlation between muscle hardness and passive and total tension, with a significant positive slope (passive tension: r = 0.986, P < 0.001; total tension: r = 0.856, P < 0.001). In conclusion, our results suggest that muscle hardness depends on muscle tension in most ranges of muscle length in the length-tension diagram.

  19. Simultaneous Knee Extensor Muscle Action Induces an Increase in Voluntary Force Generation of Plantar Flexor Muscles.

    PubMed

    Suzuki, Takahito; Shioda, Kohei; Kinugasa, Ryuta; Fukashiro, Senshi

    2017-02-01

    Suzuki, T, Shioda, K, Kinugasa, R, and Fukashiro, S. Simultaneous knee extensor muscle action induces an increase in voluntary force generation of plantar flexor muscles. J Strength Cond Res 31(2): 365-371, 2017-Maximum activation of the plantar flexor muscles is required for various sporting activities that involve simultaneous plantar flexion and knee extension. During a multi-joint movement, activation of the plantar flexor muscles is affected by the activity of the knee extensor muscles. We hypothesized that coactivation of the plantar flexor muscles and knee extensor muscles would result in a higher plantar flexion torque. To test this hypothesis, 8 male volunteers performed maximum voluntary isometric action of the plantar flexor muscles with and without isometric action of the knee extensor muscles. Surface electromyographic data were collected from 8 muscles of the right lower limb. Voluntary activation of the triceps surae muscles, evaluated using the interpolated twitch technique, significantly increased by 6.4 percentage points with intentional knee extensor action (p = 0.0491). This finding is in line with a significant increase in the average rectified value of the electromyographic activity of the vastus lateralis, fibularis longus, and soleus muscles (p = 0.013, 0.010, and 0.045, respectively). The resultant plantar flexion torque also significantly increased by 11.5% of the predetermined maximum (p = 0.031). These results suggest that higher plantar flexor activation coupled with knee extensor activation facilitates force generation during a multi-joint task.

  20. Increase in passive muscle tension of the quadriceps muscle heads in jumping athletes with patellar tendinopathy.

    PubMed

    Zhang, Z J; Ng, G Y F; Lee, W C; Fu, S N

    2016-08-19

    To investigate the passive muscle tension of the quadriceps muscle heads in male athletes clinically diagnosed with patellar tendinopathy (PT) with those of healthy controls and explore the interplay between passive muscle tension and patellar tendon stiffness. Between November 2012 and December 2013, 66 male athletes (mean age of 21.1 ± 4.4 years) were examined using supersonic shear wave imaging technology. The passive tension of the vastus lateralis (VL) and rectus femoris (RF) muscles and patellar tendon stiffness were assessed. The shear elastic modulus of the VL muscle was increased by 26.5% (P < 0.001) in the subjects with PT when compared with the controls. Greater passive tension in the VL was associated with higher patellar tendon stiffness (r = 0.38; P = 0.001). The vastus lateralis muscle of the quadriceps shows increase in passive muscle tension in jumping athletes with patellar tendinopathy. These findings suggest that increase in muscle tension is not similar in the individual muscles of the quadriceps muscle. Traditional stretching of the whole quadriceps muscle might not be targeted to the tight muscle heads.

  1. Relationship between function of masticatory muscle in mouse and properties of muscle fibers.

    PubMed

    Abe, Shinichi; Hiroki, Emi; Iwanuma, Osamu; Sakiyama, Koji; Shirakura, Yoshitaka; Hirose, Daiki; Shimoo, Yoshiaki; Suzuki, Masashi; Ikari, Yasutoyo; Kikuchi, Ryusuke; Ide, Yoshinobu; Yoshinari, Masao

    2008-05-01

    Mammals exhibit marked morphological differences in the muscles surrounding the jaw bone due to differences in eating habits. Furthermore, the myofiber properties of the muscles differ with function. Since the muscles in the oral region have various functions such as eating, swallowing, and speech, it is believed that the functional role of each muscle differs. Therefore, to clarify the functional role of each masticatory muscle, the myofiber properties of the adult mouse masticatory muscles were investigated at the transcriptional level. Expression of MyHC-2b with a fast contraction rate and strong force was frequently noted in the temporal and masseter muscles. This suggests that the temporal and masseter muscles are closely involved in rapid antero-posterior masticatory movement, which is characteristic in mice. Furthermore, expression of MyHC-1 with a low contraction rate and weak continuous force was frequently detected in the lateral pterygoid muscle. This suggests that, in contrast to other masticatory muscles, mouse lateral pterygoid muscle is not involved in fast masticatory movement, but is involved in functions requiring continuous force such as retention of jaw position. This study revealed that muscles with different roles function comprehensively during complicated masticatory movement.

  2. Human jaw muscle strength and size in relation to limb muscle strength and size.

    PubMed

    Raadsheer, M C; Van Eijden, T M G J; Van Ginkel, F C; Prahl-Andersen, B

    2004-10-01

    The aim of the present study was to investigate to what extent general factors (e.g. genotype, hormones) and factors at the craniofacial level (e.g. craniofacial size, jaw muscle architecture) contribute to the size and strength of the jaw muscles. A strong relationship of jaw muscle size and strength with that of other muscles would argue for general influences, whereas a weak relationship would argue for craniofacial influences. In 121 adult individuals, moments of maximal bite force, arm flexion force and leg extension force were measured. In addition, thicknesses of jaw muscles, arm flexor muscles and leg extensor muscles were measured using ultrasound. Relationships were assessed by using a principal component analysis. In females, one component was found in which all force moments were represented. Bite force moment, however, loaded very low. In males, two components were found. One component loaded for arm flexion and leg extension moments, the other loaded for bite force moments. In both females and males, only one component was found for the muscle thicknesses in which all muscle groups loaded similarly. It was concluded that the size of the jaw muscles was significantly related to the size of the limb muscles, suggesting that they were both subject to the same general influences. Maximal voluntary bite force moments were not significantly related to the moments of the arm flexion and leg extension forces, suggesting that besides the general influence on the muscle size, variation in bite force moment was also influenced by local variables, such as craniofacial morphology.

  3. Regulation of skeletal muscle oxidative capacity and muscle mass by SIRT3

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have previously reported that the expression of mitochondrial deacetylase SIRT3 is high in the slow oxidative muscle and that the expression of muscle SIRT3 level is increased by dietary restriction or exercise training. To explore the function of SIRT3 in skeletal muscle, we report here the esta...

  4. Objective Evaluation of Muscle Strength in Infants with Hypotonia and Muscle Weakness

    ERIC Educational Resources Information Center

    Reus, Linda; van Vlimmeren, Leo A.; Staal, J. Bart; Janssen, Anjo J. W. M.; Otten, Barto J.; Pelzer, Ben J.; Nijhuis-van der Sanden, Maria W. G.

    2013-01-01

    The clinical evaluation of an infant with motor delay, muscle weakness, and/or hypotonia would improve considerably if muscle strength could be measured objectively and normal reference values were available. The authors developed a method to measure muscle strength in infants and tested 81 typically developing infants, 6-36 months of age, and 17…

  5. Comparison between muscle activation measured by electromyography and muscle thickness measured using ultrasonography for effective muscle assessment.

    PubMed

    Kim, Chang-Yong; Choi, Jong-Duk; Kim, Suhn-Yeop; Oh, Duck-Won; Kim, Jin-Kyung; Park, Ji-Whan

    2014-10-01

    In this study, we aimed to compare the intrarater reliability and validity of muscle thickness measured using ultrasonography (US) and muscle activity via electromyography (EMG) during manual muscle testing (MMT) of the external oblique (EO) and lumbar multifidus (MF) muscles. The study subjects were 30 healthy individuals who underwent MMT at different grades. EMG was used to measure the muscle activity in terms of ratio to maximum voluntary contraction (MVC) and root mean square (RMS) metrics. US was used to measure the raw muscle thickness, the ratio of muscle thickness at MVC, and the ratio of muscle thickness at rest. One examiner performed measurements on each subject in 3 trials. The intrarater reliabilities of the % MVC RMS and raw RMS metrics for EMG and the % MVC thickness metrics for US were excellent (ICC=0.81-0.98). There was a significant difference between all the grades measured using the % MVC thickness metric (p<0.01). Further, this % MVC thickness metric of US showed a significantly higher correlation with the EMG measurement methods than with the others (r=0.51-0.61). Our findings suggest that the % MVC thickness determined by US was the most sensitive of all methods for assessing the MMT grade.

  6. Exercise-Associated Muscle Cramps

    PubMed Central

    Miller, Kevin C.; Stone, Marcus S.; Huxel, Kellie C.; Edwards, Jeffrey E.

    2010-01-01

    Context: Exercise-associated muscle cramps (EAMC) are a common condition experienced by recreational and competitive athletes. Despite their commonality and prevalence, their cause remains unknown. Theories for the cause of EAMC are primarily based on anecdotal and observational studies rather than sound experimental evidence. Without a clear cause, treatments and prevention strategies for EAMC are often unsuccessful. Evidence Acquisition: A search of Medline (EBSCO), SPORTDiscus, and Silverplatter (CINHAL) was undertaken for journal articles written in English between the years 1955 and 2008. Additional references were collected by a careful analysis of the citations of others’ research and textbooks. Results: Dehydration/electrolyte and neuromuscular causes are the most widely discussed theories for the cause of EAMC; however, strong experimental evidence for either theory is lacking. Conclusions: EAMC are likely due to several factors coalescing to cause EAMC. The variety of treatments and prevention strategies for EAMC are evidence of the uncertainty in their cause. Acute EAMC treatment should focus on moderate static stretching of the affected muscle followed by a proper medical history to determine any predisposing conditions that may have triggered the onset of EAMC. Based on physical findings, prevention programs should be implemented to include fluid and electrolyte balance strategies and/or neuromuscular training. PMID:23015948

  7. Regulatory T cells and skeletal muscle regeneration.

    PubMed

    Schiaffino, Stefano; Pereira, Marcelo G; Ciciliot, Stefano; Rovere-Querini, Patrizia

    2017-02-01

    Skeletal muscle regeneration results from the activation and differentiation of myogenic stem cells, called satellite cells, located beneath the basal lamina of the muscle fibers. Inflammatory and immune cells have a crucial role in the regeneration process. Acute muscle injury causes an immediate transient wave of neutrophils followed by a more persistent infiltration of M1 (proinflammatory) and M2 (anti-inflammatory/proregenerative) macrophages. New studies show that injured muscle is also infiltrated by a specialized population of regulatory T (Treg) cells, which control both the inflammatory response, by promoting the M1-to-M2 switch, and the activation of satellite cells. Treg cells accumulate in injured muscle in response to specific cytokines, such as IL-33, and promote muscle growth by releasing growth factors, such as amphiregulin. Muscle repair during aging is impaired due to reduced number of Treg cells and can be enhanced by IL-33 supplementation. Migration of Treg cells could also contribute to explain the effect of heterochronic parabiosis, whereby muscle regeneration of aged mice can be improved by a parabiotically linked young partners. In mdx dystrophin-deficient mice, a model of human Duchenne muscular dystrophy, muscle injury, and inflammation is mitigated by expansion of the Treg-cell population but exacerbated by Treg-cell depletion. These findings support the notion that immunological mechanisms are not only essential in the response to pathogenic microbes and tumor cells but also have a wider homeostatic role in tissue repair, and open new perspectives for boosting muscle growth in chronic muscle disease and during aging.

  8. THE HISTOGENESIS OF RAT INTERCOSTAL MUSCLE

    PubMed Central

    Kelly, A. M.; Zacks, S. I.

    1969-01-01

    Intercostal muscle from fetal and newborn rats was examined with the electron microscope. At 16 days' gestation, the developing muscle was composed of primary generations of myotubes, many of which were clustered together in groups. Within these groups, the membranes of neighboring myotubes were interconnected by specialized junctions, including tight junctions. Morphologically undifferentiated cells surrounded the muscle groups, frequently extended pseudopodia along the interspace between adjacent myotubes, and appeared to separate neighboring myotubes from one another. At 18 and 20 days' gestation, the muscle was also composed of groups of cells but the structure of the groups differed from that of the groups observed at 16 days. Single, well differentiated myotubes containing much central glycogen and peripheral myofibrils dominated each group. These large cells were interpreted as primary myotubes. Small, less differentiated muscle cells and undifferentiated cells clustered around their walls. Each cluster was ensheated by a basal lamina. The small cells were interpreted as primordia of new generations of muscle cells which differentiated by appositional growth along the walls of the large primary myotubes. All generations of rat intercostal muscle cells matured to myofibers between 20 days' gestation and birth. Coincidentally, large and small myofibers diverged from each other, leading to disintegration of the groups of muscle cells. Undifferentiated cells frequently occurred in the interspaces between neighboring muscle cells at the time of separation. Myofibers arising at different stages of muscle histogenesis intermingled in a checkerboard fashion as a result of this asynchronous mode of development. The possibility of fusion between neighboring muscle cells in this developing system is discussed. PMID:5786979

  9. Distinct muscle fascicle length changes in feline medial gastrocnemius and soleus muscles during slope walking.

    PubMed

    Maas, Huub; Gregor, Robert J; Hodson-Tole, Emma F; Farrell, Brad J; Prilutsky, Boris I

    2009-04-01

    On the basis of differences in physiology, e.g., histochemical properties and spindle density, and the structural design of the cat soleus (SO) and medial gastrocnemius (MG) muscles, we hypothesized that 1) fascicle length changes during overground walking would be both muscle and slope dependent, which would have implications for the muscles' force output as well as sensory function, and that 2) muscle-tendon unit (MTU) and fascicle length changes would be different, in which case MTU length could not be used as an indicator of muscle spindle strain. To test these hypotheses, we quantified muscle fascicle length changes and compared them with length changes of the whole MTU in the SO and MG during overground walking at various slopes (0, +/- 25, +/- 50, +75, and +100%). The SO and MG were surgically instrumented with sonomicrometry crystals and fine-wire electromyogram electrodes to measure changes in muscle fascicle length and muscle activity, respectively. MTU lengths were calculated using recorded ankle and knee joint angles and a geometric model of the hindlimb. The resultant joint moments were calculated using inverse dynamics analysis to infer muscle loading. It was found that although MTU length and velocity profiles of the SO and MG appeared similar, length changes and velocities of muscle fascicles were substantially different between the two muscles. Fascicle length changes of both SO and MG were significantly affected by slope intensity acting eccentrically in downslope walking (-25 to -50%) and concentrically in upslope walking (+25 to +100%). The differences in MTU and fascicle behaviors in both the SO and MG muscles during slope walking were explained by the three distinct features of these muscles: 1) the number of joints spanned, 2) the pennation angle, and 3) the in-series elastic component. It was further suggested that the potential role of length feedback from muscle spindles is both task and muscle dependent.

  10. Effect of repeated forearm muscle cooling on the adaptation of skeletal muscle metabolism in humans

    NASA Astrophysics Data System (ADS)

    Wakabayashi, Hitoshi; Nishimura, Takayuki; Wijayanto, Titis; Watanuki, Shigeki; Tochihara, Yutaka

    2017-01-01

    This study aimed to investigate the effect of repeated cooling of forearm muscle on adaptation in skeletal muscle metabolism. It is hypothesized that repeated decreases of muscle temperature would increase the oxygen consumption in hypothermic skeletal muscle. Sixteen healthy males participated in this study. Their right forearm muscles were locally cooled to 25 °C by cooling pads attached to the skin. This local cooling was repeated eight times on separate days for eight participants (experimental group), whereas eight controls received no cold exposure. To evaluate adaptation in skeletal muscle metabolism, a local cooling test was conducted before and after the repeated cooling period. Change in oxy-hemoglobin content in the flexor digitorum at rest and during a 25-s isometric handgrip (10% maximal voluntary construction) was measured using near-infrared spectroscopy at every 2 °C reduction in forearm muscle temperature. The arterial blood flow was occluded for 15 s by upper arm cuff inflation at rest and during the isometric handgrip. The oxygen consumption in the flexor digitorum muscle was evaluated by a slope of the oxy-hemoglobin change during the arterial occlusion. In the experimental group, resting oxygen consumption in skeletal muscle did not show any difference between pre- and post-intervention, whereas muscle oxygen consumption during the isometric handgrip was significantly higher in post-intervention than in pre-test from thermoneutral baseline to 31 °C muscle temperature (P < 0.05). This result indicated that repeated local muscle cooling might facilitate oxidative metabolism in the skeletal muscle. In summary, skeletal muscle metabolism during submaximal isometric handgrip was facilitated after repeated local muscle cooling.

  11. Bilateral Tensor Fasciae Suralis Muscles in a Cadaver with Unilateral Accessory Flexor Digitorum Longus Muscle

    PubMed Central

    Herrin, Sean O.

    2017-01-01

    Muscle variants are routinely encountered in the dissection laboratory and in clinical practice and therefore anatomists and clinicians need to be aware of their existence. Here we describe two different accessory muscles identified while performing educational dissection of a 51-year-old male cadaver. Tensor fasciae suralis, a rare muscle variant, was identified bilaterally and accessory flexor digitorum longus, a more common muscle variant, was present unilaterally. Tensor fasciae suralis and accessory flexor digitorum longus are clinically relevant muscle variants. To our knowledge, the coexistence of tensor fasciae suralis and accessory flexor digitorum longus in the same individual has not been reported in either cadaveric or imaging studies. PMID:28210274

  12. Bilateral Tensor Fasciae Suralis Muscles in a Cadaver with Unilateral Accessory Flexor Digitorum Longus Muscle.

    PubMed

    Bale, Logan S W; Herrin, Sean O

    2017-01-01

    Muscle variants are routinely encountered in the dissection laboratory and in clinical practice and therefore anatomists and clinicians need to be aware of their existence. Here we describe two different accessory muscles identified while performing educational dissection of a 51-year-old male cadaver. Tensor fasciae suralis, a rare muscle variant, was identified bilaterally and accessory flexor digitorum longus, a more common muscle variant, was present unilaterally. Tensor fasciae suralis and accessory flexor digitorum longus are clinically relevant muscle variants. To our knowledge, the coexistence of tensor fasciae suralis and accessory flexor digitorum longus in the same individual has not been reported in either cadaveric or imaging studies.

  13. Bone Marrow Stromal Cells Generate Muscle Cells and Repair Muscle Degeneration

    NASA Astrophysics Data System (ADS)

    Dezawa, Mari; Ishikawa, Hiroto; Itokazu, Yutaka; Yoshihara, Tomoyuki; Hoshino, Mikio; Takeda, Shin-ichi; Ide, Chizuka; Nabeshima, Yo-ichi

    2005-07-01

    Bone marrow stromal cells (MSCs) have great potential as therapeutic agents. We report a method for inducing skeletal muscle lineage cells from human and rat general adherent MSCs with an efficiency of 89%. Induced cells differentiated into muscle fibers upon transplantation into degenerated muscles of rats and mdx-nude mice. The induced population contained Pax7-positive cells that contributed to subsequent regeneration of muscle upon repetitive damage without additional transplantation of cells. These MSCs represent a more ready supply of myogenic cells than do the rare myogenic stem cells normally found in muscle and bone marrow.

  14. Inhibition of platelet-derived growth factor signaling prevents muscle fiber growth during skeletal muscle hypertrophy.

    PubMed

    Sugg, Kristoffer B; Korn, Michael A; Sarver, Dylan C; Markworth, James F; Mendias, Christopher L

    2017-03-01

    The platelet-derived growth factor receptors alpha and beta (PDGFRα and PDGFRβ) mark fibroadipogenic progenitor cells/fibroblasts and pericytes in skeletal muscle, respectively. While the role that these cells play in muscle growth and development has been evaluated, it was not known whether the PDGF receptors activate signaling pathways that control transcriptional and functional changes during skeletal muscle hypertrophy. To evaluate this, we inhibited PDGFR signaling in mice subjected to a synergist ablation muscle growth procedure, and performed analyses 3 and 10 days after induction of hypertrophy. The results from this study indicate that PDGF signaling is required for fiber hypertrophy, extracellular matrix production, and angiogenesis that occur during muscle growth.

  15. Comparative Associations of Muscle Mass and Muscle Strength with Mortality in Dialysis Patients

    PubMed Central

    Isoyama, Naohito; Qureshi, Abdul Rashid; Avesani, Carla Maria; Lindholm, Bengt; Bàràny, Peter; Heimbürger, Olof; Cederholm, Tommy; Stenvinkel, Peter

    2014-01-01

    Background and objectives Reduced muscle mass and strength are prevalent conditions in dialysis patients. However, muscle strength and muscle mass are not congruent; muscle strength can diminish even though muscle mass is maintained or increased. This study addresses phenotype and mortality associations of these muscle dysfunction entities alone or in combination (i.e., concurrent loss of muscle mass and strength/mobility, here defined as sarcopenia). Design, setting, participants, & measurements This study included 330 incident dialysis patients (203 men, mean age 53±13 years, and mean GFR 7±2 ml/min per 1.73 m2) recruited between 1994 and 2010 and followed prospectively for up to 5 years. Low muscle mass (by dual-energy x-ray absorptiometry appendicular mass index) and low muscle strength (by handgrip) were defined against young reference populations according to the European Working Group on Sarcopenia in Older People. Results Whereas 20% of patients had sarcopenia, low muscle mass and low muscle strength alone were observed in a further 24% and 15% of patients, respectively. Old age, comorbidities, protein-energy wasting, physical inactivity, low albumin, and inflammation associated with low muscle strength, but not with low muscle mass (multivariate ANOVA interactions). During follow-up, 95 patients (29%) died and both conditions associated with mortality as separate entities. When combined, individuals with low muscle mass alone were not at increased risk of mortality (adjusted hazard ratio [HR], 1.23; 95% confidence interval [95% CI], 0.56 to 2.67). Individuals with low muscle strength were at increased risk, irrespective of their muscle stores being appropriate (HR, 1.98; 95% CI, 1.01 to 3.87) or low (HR, 1.93; 95% CI, 1.01 to 3.71). Conclusions Low muscle strength was more strongly associated with aging, protein-energy wasting, physical inactivity, inflammation, and mortality than low muscle mass. Assessment of muscle functionality may provide additional

  16. Conchotome and needle percutaneous biopsy of skeletal muscle.

    PubMed Central

    Dietrichson, P; Coakley, J; Smith, P E; Griffiths, R D; Helliwell, T R; Edwards, R H

    1987-01-01

    Percutaneous muscle biopsy is an important and acceptable technique in the study of conditions involving human skeletal muscle. A review of 436 conchotome and needle muscle biopsies obtained over 18 months in this centre is presented. Images PMID:3694206

  17. Genetics Home Reference: myostatin-related muscle hypertrophy

    MedlinePlus

    ... Conditions myostatin-related muscle hypertrophy myostatin-related muscle hypertrophy Enable Javascript to view the expand/collapse boxes. ... Open All Close All Description Myostatin-related muscle hypertrophy is a rare condition characterized by reduced body ...

  18. Vascular smooth muscle phenotypic diversity and function

    PubMed Central

    2010-01-01

    The control of force production in vascular smooth muscle is critical to the normal regulation of blood flow and pressure, and altered regulation is common to diseases such as hypertension, heart failure, and ischemia. A great deal has been learned about imbalances in vasoconstrictor and vasodilator signals, e.g., angiotensin, endothelin, norepinephrine, and nitric oxide, that regulate vascular tone in normal and disease contexts. In contrast there has been limited study of how the phenotypic state of the vascular smooth muscle cell may influence the contractile response to these signaling pathways dependent upon the developmental, tissue-specific (vascular bed) or disease context. Smooth, skeletal, and cardiac muscle lineages are traditionally classified into fast or slow sublineages based on rates of contraction and relaxation, recognizing that this simple dichotomy vastly underrepresents muscle phenotypic diversity. A great deal has been learned about developmental specification of the striated muscle sublineages and their phenotypic interconversions in the mature animal under the control of mechanical load, neural input, and hormones. In contrast there has been relatively limited study of smooth muscle contractile phenotypic diversity. This is surprising given the number of diseases in which smooth muscle contractile dysfunction plays a key role. This review focuses on smooth muscle contractile phenotypic diversity in the vascular system, how it is generated, and how it may determine vascular function in developmental and disease contexts. PMID:20736412

  19. A rare variation of the digastric muscle

    PubMed Central

    KALNIEV, MANOL; KRASTEV, DIMO; KRASTEV, NIKOLAY; VIDINOV, KALIN; VELTCHEV, LUDMIL; APOSTOLOV, ALEXANDER; MILEVA, MILKA

    2013-01-01

    The digastric muscle is composed by two muscle bellies: an anterior and a posterior, joined by an intermediate tendon. This muscle is situated in the anterior region of the neck. The region between the hyoid bone and the mandible is divided by an anterior belly into two triangles: the submandibular situated laterally and the submental triangle which is located medially. We found that the anatomical variations described in the literature relate mainly to the anterior belly and consist of differences in shape and attachment of the muscle. During routine dissection in February 2013 in the section hall of the Department of Anatomy and Histology in Medical University – Sofia we came across a very interesting variation of the digastric muscle. The digastric muscles that presented anatomical variations were photographed using a Sony Cyber-shot DSC-T1 camera, with a Carl Zeiss Vario-Tessar lens. We found out bilateral variation of the digastric muscle in one cadaver. The anterior bellies were very thin and insert to the hyoid bone. Two anterior bellies connect each other and thus they formed a loop. The anatomical variations observed of our study related only to the anterior belly, as previously described by other authors. It is very important to consider the occurrence of the above mentioned variations in the digastric muscle when surgical procedures are performed on the anterior region of the neck. PMID:26527971

  20. Addison's disease presenting with muscle spasm.

    PubMed

    Bhattacharjee, Rana; Sharma, A; Rays, A; Thakur, I; Sarkar, D; Mandal, B; Mookerjee, S K; Chatterjee, S K; Chowdhury, Pradip Roy

    2013-09-01

    Primary hypoadrenalism has various causes and protean manifestation. We report a young female patient who presented with severe muscle spasm as her primary complaint. On evaluation she was found to be a case of Addison's disease secondary to adrenal tuberculosis. Her muscle spasm disappeared rapidly with replacement dose of glucocorticoid.