3,477 research outputs found
Short-Interval Cortical Inhibition and Intracortical Facilitation during Submaximal Voluntary Contractions Changes with Fatigue
This study determined whether short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) change during a sustained submaximal isometric contraction. On 2 days, 12 participants (6 men, 6 women) performed brief (7-s) elbow flexor contractions before and after a 10-min fatiguing contraction; all contractions were performed at the level of integrated electromyographic activity (EMG) which produced 25 % maximal unfatigued torque. During the brief 7-s and 10-min submaximal contractions, single (test) and paired (conditioning–test) transcranial magnetic stimuli were applied over the motor cortex (5 s apart) to elicit motor-evoked potentials (MEPs) in biceps brachii. SICI and ICF were elicited on separate days, with a conditioning–test interstimulus interval of 2.5 and 15 ms, respectively. On both days, integrated EMG remained constant while torque fell during the sustained contraction by ~51.5 % from control contractions, perceived effort increased threefold, and MVC declined by 21–22 %. For SICI, the conditioned MEP during control contractions (74.1 ± 2.5 % of unconditioned MEP) increased (less inhibition) during the sustained contraction (last 2.5 min: 86.0 ± 5.1 %; P \u3c 0.05). It remained elevated in recovery contractions at 2 min (82.0 ± 3.8 %; P \u3c 0.05) and returned toward control at 7-min recovery (76.3 ± 3.2 %). ICF during control contractions (conditioned MEP 129.7 ± 4.8 % of unconditioned MEP) decreased (less facilitation) during the sustained contraction (last 2.5 min: 107.6 ± 6.8 %; P \u3c 0.05) and recovered to 122.8 ± 4.3 % during contractions after 2 min of recovery. Both intracortical inhibitory and facilitatory circuits become less excitable with fatigue when assessed during voluntary activity, but their different time courses of recovery suggest different mechanisms for the fatigue-related changes of SICI and ICF
Crystal structure of human IPS-1/MAVS/VISA/Cardif caspase activation recruitment domain
<p>Abstract</p> <p>Background</p> <p>IPS-1/MAVS/VISA/Cardif is an adaptor protein that plays a crucial role in the induction of interferons in response to viral infection. In the initial stage of the intracellular antiviral response two RNA helicases, retinoic acid inducible gene-I (RIG-I) and melanoma differentiation-association gene 5 (MDA5), are independently able to bind viral RNA in the cytoplasm. The 62 kDa protein IPS-1/MAVS/VISA/Cardif contains an N-terminal caspase activation and recruitment (CARD) domain that associates with the CARD regions of RIG-I and MDA5, ultimately leading to the induction of type I interferons. As a first step towards understanding the molecular basis of this important adaptor protein we have undertaken structural studies of the IPS-1 MAVS/VISA/Cardif CARD region.</p> <p>Results</p> <p>The crystal structure of human IPS-1/MAVS/VISA/Cardif CARD has been determined to 2.1Ã… resolution. The protein was expressed and crystallized as a maltose-binding protein (MBP) fusion protein. The MBP and IPS-1 components each form a distinct domain within the structure. IPS-1/MAVS/VISA/Cardif CARD adopts a characteristic six-helix bundle with a Greek-key topology and, in common with a number of other known CARD structures, contains two major polar surfaces on opposite sides of the molecule. One face has a surface-exposed, disordered tryptophan residue that may explain the poor solubility of untagged expression constructs.</p> <p>Conclusion</p> <p>The IPS-1/MAVS/VISA/Cardif CARD domain adopts the classic CARD fold with an asymmetric surface charge distribution that is typical of CARD domains involved in homotypic protein-protein interactions. The location of the two polar areas on IPS-1/MAVS/VISA/Cardif CARD suggest possible types of associations that this domain makes with the two CARD domains of MDA5 or RIG-I. The N-terminal CARD domains of RIG-I and MDA5 share greatest sequence similarity with IPS-1/MAVS/VISA/Cardif CARD and this has allowed modelling of their structures. These models show a very different charge profile for the equivalent surfaces compared to IPS-1/MAVS/VISA/Cardif CARD.</p
Tentative Evidence for Relativistic Electrons Generated by the Jet of the Young Sun-like Star DG Tau
Synchrotron emission has recently been detected in the jet of a massive
protostar, providing further evidence that certain jet formation
characteristics for young stars are similar to those found for highly
relativistic jets from AGN. We present data at 325 and 610 MHz taken with the
GMRT of the young, low-mass star DG Tau, an analog of the Sun soon after its
birth. This is the first investigation of a low-mass YSO at at such low
frequencies. We detect emission with a synchrotron spectral index in the
proximity of the DG Tau jet and interpret this emission as a prominent bow
shock associated with this outflow. This result provides tentative evidence for
the acceleration of particles to relativistic energies due to the shock impact
of this otherwise very low-power jet against the ambient medium. We calculate
the equipartition magnetic field strength (0.11 mG) and particle energy
(4x10^40 erg), which are the minimum requirements to account for the
synchrotron emission of the DG Tau bow shock. These results suggest the
possibility of low energy cosmic rays being generated by young Sun-like stars.Comment: 19 pages, 2 figures, accepted for publication in ApJ Letter
Survey-based naming conventions for use in OBO Foundry ontology development
A wide variety of ontologies relevant to the biological and medical domains are
available through the OBO Foundry portal, and their number is growing rapidly. Integration of these ontologies, while requiring considerable effort, is extremely desirable. However, heterogeneities in format and style pose serious obstacles to such integration. In particular, inconsistencies in naming conventions can impair the readability and navigability of ontology class hierarchies, and hinder their alignment and integration. While other sources of diversity are tremendously complex and challenging, agreeing a set of common naming conventions is an achievable goal, particularly if those conventions are based on lessons drawn from pooled practical
experience and surveys of community opinion. We summarize a review of existing naming conventions and highlight certain disadvantages with respect to general applicability in the biological domain. We also present the results of a survey carried out to establish which naming conventions are currently employed by OBO Foundry ontologies and to determine what their special requirements regarding the naming
of entities might be. Lastly, we propose an initial set of typographic, syntactic and semantic conventions for labelling classes in OBO Foundry ontologies. Adherence to common naming conventions is more than just a matter of aesthetics. Such conventions provide guidance to ontology creators, help developers avoid flaws and
inaccuracies when editing, and especially when interlinking, ontologies. Common naming conventions will also assist consumers of ontologies to more readily understand what meanings were intended by the authors of ontologies used in annotating bodies of data
Interference of the T cell and antigen-presenting cell costimulatory pathway using CTLA4-Ig (abatacept) prevents Staphylococcal enterotoxin B pathology
Abstract
Staphylococcal enterotoxin B (SEB) is a bacterial superantigen that binds the receptors in the APC/T cell synapse and causes increased proliferation of T cells and a cytokine storm syndrome in vivo. Exposure to the toxin can be lethal and cause significant pathology in humans. The lack of effective therapies for SEB exposure remains an area of concern, particularly in scenarios of acute mass casualties. We hypothesized that blockade of the T cell costimulatory signal by the CTLA4-Ig synthetic protein (abatacept) could prevent SEB-dependent pathology. In this article, we demonstrate mice treated with a single dose of abatacept 8 h post SEB exposure had reduced pathology compared with control SEB-exposed mice. SEB-exposed mice showed significant reductions in body weight between days 4 and 9, whereas mice exposed to SEB and also treated with abatacept showed no weight loss for the duration of the study, suggesting therapeutic mitigation of SEB-induced morbidity. Histopathology and magnetic resonance imaging demonstrated that SEB mediated lung damage and edema, which were absent after treatment with abatacept. Analysis of plasma and lung tissues from SEB-exposed mice treated with abatacept demonstrated significantly lower levels of IL-6 and IFN-γ (p &lt; 0.0001), which is likely to have resulted in less pathology. In addition, exposure of human and mouse PBMCs to SEB in vitro showed a significant reduction in levels of IL-2 (p &lt; 0.0001) after treatment with abatacept, indicating that T cell proliferation is the main target for intervention. Our findings demonstrate that abatacept is a robust and potentially credible drug to prevent toxic effects from SEB exposure.</jats:p
A Study of the Effectiveness of Water Resources Planning Groups A Final Report
Information and recommendations were developed pertaining to the organization of regional and river basin water planning studies, useful to river basin commissions and others responsible for such studies. The approach that was used included four basic components: (1) conceptualization of a planning model, based on an analysis of planning theory and organizational literature, (2) analysis and review of historical trends in water resources planned, (3) examination and comparative evaluation of 15 river basin planning studies, and (4) case studies of two planning efforts selected from the 15 examined in order to perform a more detailed analysis and to gain information about the informal aspects of the planning process that took place. In connection with the formulation of the planning model, a substantial amount of research effort was committed to the development of a computer simulation of decision-making in the planning or policy formulation process. This programmed simulation is designed to be a useful planning tool for gaining insights into the interrelationships among objectives, alternative courses of action, and political feasibility. A description of the simulation model and an analysis of tis application to the Willamette River Basin Comprehensive Study are presented
The Ursinus Weekly, January 10, 1944
Fine cast chosen for coming play, Jupiter Laughs • Ensign Miriam Waltemyer to speak on Navy waves • Senator Ball will speak at Ursinus this Wednesday on post-war world • Ursinus honor grad to speak tonight • Dorothy Waltz engaged • Intersorority dance postponed • Students joyful at belated banquet • Rosicrucians elect girls to fill coveted offices • Memorial marks site of girls\u27 seminary • Post-war employment ideas solicited in Pabst contest • Dr. Hartzell holds office on Collegeville council • Combined Y\u27s will sponsor amateur night on Friday • Rev. Shaffer addresses student body at vespers • Ursinus students speak • Publishers offer awards to writers in services • German Club features sing • James Boswell to teach mathematics at Illinois • Leona Miller to give make-up demonstration • Captain Fury presented • Loraine Walton to review Taps for Private Tussie • The librarian\u27s angle • Courtmen lose close tilt to F. & M. when Mackin scores in last minute • Garnet crushes Ursinus grapplers • Carney beats Shope in intramural games • Men\u27s varsity defeats Valley Forge hospital • Five girls return from 1943 varsity • Freshman receives rating in 1943 tennis lineup • Basketball five downs Superior Tube team • War cannot stop Russian colleges • Ursinus students flock to Thompson-Gay gymhttps://digitalcommons.ursinus.edu/weekly/1722/thumbnail.jp
Systematic Modification of Zingerone Reveals Structural Requirements for Attraction of Jarvis’s Fruit Fly
Tephritid fruit flies are amongst the most significant horticultural pests globally and male chemical lures are important for monitoring and control. Zingerone has emerged as a unique male fruit fly lure that can attract dacine fruit flies that are weakly or non-responsive to methyl eugenol and cuelure. However, the key features of zingerone that mediate this attraction are unknown. As Jarvis’s fruit fly, Bactrocera jarvisi (Tryon), is strongly attracted to zingerone, we evaluated the response of B. jarvisi to 37 zingerone analogues in a series of field trials to elucidate the functional groups involved in attraction. The most attractive analogues were alkoxy derivatives, with isopropoxy being the most attractive, followed by ethoxy and trifluoromethoxy analogues. All of the phenolic esters tested were also attractive with the response typically decreasing with increasing size of the ester. Results indicate that the carbonyl group, methoxy group, and phenol of zingerone are key sites for the attraction of B. jarvisi and identify some constraints on the range of structural modifications that can be made to zingerone without compromising attraction. These findings are important for future work in developing and optimising novel male chemical lures for fruit flies
The contribution of TRPC1, TRPC3, TRPC5 and TRPC6 to touch and hearing
Transient receptor potential channels have diverse roles in mechanosensation. Evidence is accumulating that members of the canonical subfamily of TRP channels (TRPC) are involved in touch and hearing. Characteristic features of TRP channels include their high structural homology and their propensity to form heteromeric complexes which suggests potential functional redundancy. We previously showed that TRPC3 and TRPC6 double knockout animals have deficits in light touch and hearing whilst single knockouts were apparently normal. We have extended these studies to analyse deficits in global quadruple TRPC1, 3, 5 and 6 null mutant mice. We examined both touch and hearing in behavioural and electrophysiological assays, and provide evidence that the quadruple knockout mice have larger deficits than the TRPC3 TRPC6 double knockouts. Mechano-electrical transducer currents of cochlear outer hair cells were however normal. This suggests that TRPC1, TRPC3, TRPC5 and TRPC6 channels contribute to cutaneous and auditory mechanosensation in a combinatorial manner, but have no direct role in cochlear mechanotransduction
Survey-based naming conventions for use in OBO Foundry ontology development
<p>Abstract</p> <p>Background</p> <p>A wide variety of ontologies relevant to the biological and medical domains are available through the OBO Foundry portal, and their number is growing rapidly. Integration of these ontologies, while requiring considerable effort, is extremely desirable. However, heterogeneities in format and style pose serious obstacles to such integration. In particular, inconsistencies in naming conventions can impair the readability and navigability of ontology class hierarchies, and hinder their alignment and integration. While other sources of diversity are tremendously complex and challenging, agreeing a set of common naming conventions is an achievable goal, particularly if those conventions are based on lessons drawn from pooled practical experience and surveys of community opinion.</p> <p>Results</p> <p>We summarize a review of existing naming conventions and highlight certain disadvantages with respect to general applicability in the biological domain. We also present the results of a survey carried out to establish which naming conventions are currently employed by OBO Foundry ontologies and to determine what their special requirements regarding the naming of entities might be. Lastly, we propose an initial set of typographic, syntactic and semantic conventions for labelling classes in OBO Foundry ontologies.</p> <p>Conclusion</p> <p>Adherence to common naming conventions is more than just a matter of aesthetics. Such conventions provide guidance to ontology creators, help developers avoid flaws and inaccuracies when editing, and especially when interlinking, ontologies. Common naming conventions will also assist consumers of ontologies to more readily understand what meanings were intended by the authors of ontologies used in annotating bodies of data.</p
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