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311.
Central processing of inertial sensory information about head attitude and motion in space is crucial for motor control. Vestibular signals are coded relative to a non-inertial system, the head, that is virtually continuously in motion. Evidence for transformation of vestibular signals from head-fixed sensory coordinates to gravity-centered coordinates have been provided by studies of the vestibulo-ocular reflex. The underlying central processing depends on otolith afferent information that needs to be resolved in terms of head translation related inertial forces and head attitude dependent pull of gravity. Theoretical solutions have been suggested, but experimental evidence is still scarce. It appears, along these lines, that gaze control systems are intimately linked to motor control of head attitude and posture. 相似文献
312.
Deuterostome phylogeny and the sister group of the chordates: evidence from molecules and morphology 总被引:13,自引:3,他引:10
Complete coding regions of the 18S rRNA gene of an enteropneust
hemichordate and an echinoid and ophiuroid echinoderm were obtained and
aligned with 18S rRNA gene sequences of all major chordate clades and four
outgroups. Gene sequences were analyzed to test morphological character
phylogenies and to assess the strength of the signal. Maximum- parsimony
analysis of the sequences fails to support a monophyletic Chordata; the
urochordates form the sister taxon to the hemichordates, and together this
clade plus the echinoderms forms the sister taxon to the cephalochordates
plus craniates. Decay, bootstrap, and tree-length distribution analyses
suggest that the signal for inference of dueterostome phylogeny is weak in
this molecule. Parsimony analysis of morphological plus molecular
characters supports both monophyly of echinoderms plus enteropneust
hemichordates and a sister group relationship of this clade to chordates.
Evolutionary parsimony does not support chordate monophyly.
Neighbor-joining, Fitch-Margoliash, and maximum-likelihood analyses support
a chordate lineage that is the sister group to an
echinoderm-plus-hemichordate lineage. The results illustrate both the
limitations of the 18S rRNA molecule alone for high- level phylogeny
inference and the importance of considering both molecular and
morphological data in phylogeny reconstruction.
相似文献
313.
314.
Philippe GAC Vanden Bergh Thomas Fett Laurent LM Zecchinon Anne VT Thomas Daniel JM Desmecht 《BMC veterinary research》2005,1(1):1-7
Background
Lymphocyte function-associated antigen-1 (LFA-1, CD11a/CD18, alphaLbeta2), the most abundant and widely expressed beta2-integrin, is required for many cellular adhesive interactions during the immune response. Many studies have shown that LFA-1 is centrally involved in the pathogenesis of several diseases caused by Repeats-in-toxin (RTX) -producing bacteria. 相似文献315.
Rieke Alten Hermann Gram Leo A Joosten Bvanden Wim Berg Joachim Sieper Siegfrid Wassenberg Gerd Burmester Piet van Riel Maria Diaz-Lorente Gerardus JM Bruin Thasia G Woodworth Christiane Rordorf Yannik Batard Andrew M Wright Thomas Jung 《Arthritis research & therapy》2008,10(3):1-9
Introduction
IL-1β is a proinflammatory cytokine driving joint inflammation as well as systemic signs of inflammation, such as fever and acute phase protein production.Methods
ACZ885, a fully human monoclonal antibody that neutralizes the bioactivity of human IL-1β, was generated to study the potent and long-lasting neutralization of IL-1β in mechanistic animal models as well as in a proof-of-concept study in patients with rheumatoid arthritis (RA).Results
The mouse IL-1 receptor cross-reacts with human IL-1β, and it was demonstrated that ACZ885 can completely suppress IL-1β-mediated joint inflammation and cartilage destruction in mice. This observation prompted us to study the safety, tolerability and pharmacodynamic activity of ACZ885 in RA patients in a small proof-of-concept study – the first to be conducted in humans. Patients with active RA despite treatment with stable doses of methotrexate were enrolled in this dose escalation study. The first 32 patients were split into four cohorts of eight patients each (six were randomly assigned to active treatment and two to placebo). ACZ885 doses were 0.3, 1, 3 and 10 mg/kg, administered intravenously on days 1 and 15. To explore efficacy within 6 weeks of treatment, an additional 21 patients were randomly assigned to the 10 mg/kg cohort, resulting in a total of 20 patients dosed with 10 mg/kg and 15 patients treated with placebo. There was clinical improvement (American College of Rheumatology 20% improvement criteria) at week 6 in the 10 mg/kg treatment group; however, this did not reach statistical significance (P = 0.085). A statistically significant reduction in disease activity score was observed after 4 weeks in the 10 mg/kg group. Onset of action was rapid, because most responders exhibited improvement in their symptoms within the first 3 weeks. C-reactive protein levels decreased in patients treated with ACZ885 within 1 week. ACZ885 was well tolerated. Three patients receiving ACZ885 developed infectious episodes that required treatment. No anti-ACZ885 antibodies were detected during the study.Conclusion
ACZ885 administration to methotrexate-refractory patients resulted in clinical improvement in a subset of patients. Additional studies to characterize efficacy in RA and to determine the optimal dose regimen appear warranted.Trial Registration
ClinicalTrials.gov identifier NCT00619905. 相似文献316.
317.
Opstelten W Van Wijck AJ Van Essen GA Buskens E Bak AA Kalkman CJ Verheij TJ Moons KG 《BMC anesthesiology》2004,4(1):2-7
BACKGROUND: Postherpetic neuralgia (PHN) is by far the most common complication of herpes zoster (HZ) and one of the most intractable pain disorders. Since PHN is seen most often in the elderly, the number of patients with this disorder is expected to increase in our ageing society. PHN may last for months to years and has a high impact on the quality of life. The results of PHN treatment are rather disappointing. Epidural injection of local anaesthetics and steroids in the acute phase of HZ is a promising therapy for the prevention of PHN. Since randomised trials on the effectiveness of this intervention are lacking, the PINE (Prevention by epidural Injection of postherpetic Neuralgia in the Elderly) study was set up. The PINE study compares the effectiveness and cost-effectiveness of a single epidural injection of local anaesthetics and steroids during the acute phase of HZ with that of care-as-usual (i.e. antivirals and analgesics) in preventing PHN in elderly patients. METHODS / DESIGN: The PINE study is an open, multicenter clinical trial in which 550 elderly (age >/= 50 yr.) patients who consult their general practitioner in the acute phase of HZ (rash < 7 days) are randomised to one of the treatment groups. The primary clinical endpoint is the presence of HZ-related pain one month after the onset of the rash. Secondary endpoints include duration and severity of pain, re-interventions aiming to treat the existing pain, side effects, quality of life, and cost-effectiveness. CONCLUSION: The PINE study is aimed to quantify the (cost-) effectiveness of a single epidural injection during the acute phase of HZ on the prevention of PHN. 相似文献
318.
Lall AB Ventura DS Bechara EJ de Souza JM Colepicolo-Neto P Viviani VR 《Journal of insect physiology》2000,46(7):1137-1141
The presence of two spectral mechanisms, near-ultraviolet and green (lambda(max)=545nm), is strongly suggested by electroretinographic visual spectral sensitivity curves obtained under dark and red chromatic adaptation conditions in the compound eyes of the click beetle Pyrophorus punctatissimus. The bioluminescence emission of the dorsal prothoracic lanterns is deep green (lambda(max)=543nm) and that of the ventral abdominal lantern is lime green (lambda(max)=556nm) in colour in P. punctatissimus. A broad green visual receptor would detect both deep green and lime green bioluminescent optical signals. 相似文献
319.
Hendrikus JM Lemmens Mohammad I El-Orbany James Berry Jovino Ben Morte Jr Gavin Martin 《BMC anesthesiology》2010,10(1):1-10
Background
The perioperative period is characterized by an intense inflammatory response. Perioperative inflammation promotes postoperative morbidity and increases mortality. Blunting the inflammatory response to surgical trauma might thus improve perioperative outcomes. We are studying three interventions that potentially modulate perioperative inflammation: corticosteroids, tight glucose control, and light anesthesia.Methods/Design
The DeLiT Trial is a factorial randomized single-center trial of dexamethasone vs placebo, intraoperative tight vs. conventional glucose control, and light vs deep anesthesia in patients undergoing major non-cardiac surgery. Anesthetic depth will be estimated with Bispectral Index (BIS) monitoring (Aspect medical, Newton, MA). The primary outcome is a composite of major postoperative morbidity including myocardial infarction, stroke, sepsis, and 30-day mortality. C-reactive protein, a measure of the inflammatory response, will be evaluated as a secondary outcome. One-year all-cause mortality as well as post-operative delirium will be additional secondary outcomes. We will enroll up to 970 patients which will provide 90% power to detect a 40% reduction in the primary outcome, including interim analyses for efficacy and futility at 25%, 50% and 75% enrollment.Discussion
The DeLiT trial started in February 2007. We expect to reach our second interim analysis point in 2010. This large randomized controlled trial will provide a reliable assessment of the effects of corticosteroids, glucose control, and depth-of-anesthesia on perioperative inflammation and morbidity from major non-cardiac surgery. The factorial design will enable us to simultaneously study the effects of the three interventions in the same population, both individually and in different combinations. Such a design is an economically efficient way to study the three interventions in one clinical trial vs three.Trial registration
This trial is registered at Clinicaltrials.gov #: NTC00433251 相似文献320.
Manon JM van Oosten Radboud JEM Dolhain Jan W Koper Elisabeth FC van Rossum Marieke Emonts Khik H Han Jacques MGW Wouters Johanne MW Hazes Steven WJ Lamberts Richard A Feelders 《Arthritis research & therapy》2010,12(4):R159