955 resultados para Vocal Cord Paralysis


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Hemichordates were traditionally allied to the chordates, but recent molecular analyses have suggested that hemichordates are a sister group to the echinoderms, a relationship that has important consequences for the interpretation of the evolution of deuterostome body plans. However, the molecular phylogenetic analyses to date have not provided robust support for the hemichordate + echinoderm clade. We use a maximum likelihood framework, including the parametric bootstrap, to reanalyze DNA data from complete mitochondrial genomes and nuclear 18S rRNA. This approach provides the first statistically significant support for the hemichordate + echinoderm clade from molecular data. This grouping implies that the ancestral deuterostome had features that included an adult with a pharynx and a dorsal nerve cord and an indirectly developing dipleurula-like larva.

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Humpbacks have picked up a catchy tune sung by immigrants from a distant ocean. The song patterns of humpback whales (Megaptera novaeangliae) depend on where they live, with populations inhabiting different ocean basins normally singing quite distinct songs. Here we record a unique and radical song change in the song of humpback whales in the Pacific Ocean off the Australian east coast. Their song was replaced rapidly and completely by the song of the Australian west coast population from the Indian Ocean, apparently as a result of the introduction of only a small number of 'foreign' singers. Such a revolutionary change is unprecedented in animal cultural vocal traditions and suggests that novelty may stimulate change in humpback whale songs.

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I shall discuss the quantum and classical dynamics of a class of nonlinear Hamiltonian systems. The discussion will be restricted to systems with one degree of freedom. Such systems cannot exhibit chaos, unless the Hamiltonians are time dependent. Thus we shall consider systems with a potential function that has a higher than quadratic dependence on the position and, furthermore, we shall allow the potential function to be a periodic function of time. This is the simplest class of Hamiltonian system that can exhibit chaotic dynamics. I shall show how such systems can be realized in atom optics, where very cord atoms interact with optical dipole potentials of a far-off resonance laser. Such systems are ideal for quantum chaos studies as (i) the energy of the atom is small and action scales are of the order of Planck's constant, (ii) the systems are almost perfectly isolated from the decohering effects of the environment and (iii) optical methods enable exquisite time dependent control of the mechanical potentials seen by the atoms.

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Dendritic cells (DCs) are the most potent professional antigen-presenting cells (APCs), which play a vital role in primary immune responses. Introducing genes into DCs will allow constitutive expression of the encoded proteins and thus prolong the presentation of the antigens derived therefrom. In addition, multiple and unidentified epitopes encoded by the entire tumor-associated antigen (TAA) gene may enhance T cell activation. This study demonstrated that an HIV-1-based lentiviral vector conferred efficient gene transfer to DCs. The transgene, murine tyrosinase-related protein 2 (mTRP-2), encodes a clinically relevant melanoma-associated antigen (MAA), which has been found to be a tumor rejection antigen for B16 melanoma. The transfer and proper processing of mTRP-2 in DCs, in terms of RNA transcription activity and protein expression, were verified by RT-PCR and specific antibody, respectively. Administration of mTRP-2 gene-modified DCs (DC-HR'CmT2) to C57BL/6 mice evoked strong protection against tumor challenge, for which the presence of CD4(+) and CD8(+) cells during both the priming and challenge phase was essential. In a therapy model, our results showed that four of seven mice with preestablished tumor remained tumor free for 80 days after therapeutic vaccination. Given the results shown in this study, mTRP-2 gene transfer to DCs provides a potential therapeutic strategy for the management of melanoma, especially in the early stage of the disease.

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The phylogeny of the Australian legume genus Daviesia was estimated using sequences of the internal transcribed spacers of nuclear ribosomal DNA. Partial congruence was found with previous analyses using morphology, including strong support for monophyly of the genus and for a sister group relationship between the clade D. pachyloma and the rest of the genus. A previously unplaced bird-pollinated species, anceps + D. D. epiphyllum, was well supported as sister to the only other bird-pollinated species in the genus, D. speciosa, indicating a single origin of bird pollination in their common ancestor. Other morphological groups within Daviesia were not supported and require reassessment. A strong and previously unreported sister clade of Daviesia consists of the two monotypic genera Erichsenia and Viminaria. These share phyllode-like leaves and indehiscent fruits. The evolutionary history of cord roots, which have anomalous secondary thickening, was explored using parsimony. Cord roots are limited to three separate clades but have a complex history involving a small number of gains (most likely 0-3) and losses (0-5). The anomalous structure of cord roots ( adventitious vascular strands embedded in a parenchymatous matrix) may facilitate nutrient storage, and the roots may be contractile. Both functions may be related to a postfire resprouting adaptation. Alternatively, cord roots may be an adaptation to the low-nutrient lateritic soils of Western Australia. However, tests for association between root type, soil type, and growth habit were equivocal, depending on whether the variables were treated as phylogenetically dependent (insignificant) or independent ( significant).

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The spastic (spa) and oscillator (ot) mouse have naturally occurring mutations in the inhibitory glycine receptor (GlyR) and exhibit severe motor disturbances when exposed to unexpected sensory stimuli. We examined the effects of the spa and ot mutations on GlyR- and GABA(A)R-mediated synaptic transmission in the superficial dorsal horn (SFDH), a spinal cord region where inhibition is important for nociceptive processing. Spontaneous mIPSCs were recorded from visually identified neurones in parasagittal spinal cord slices. Neurones received exclusively GABA(A)R-mediated mIPSCs, exclusively GlyR-mediated mIPSCs or both types of mIPSCs. In control mice (wild-type and spa/+) over 40 % of neurones received both types of mIPSCs, over 30 % received solely GABA(A)R-mediated mIPSCs and the remainder received solely GlyR-mediated mIPSCs. In spa/spa animals, 97 % of the neurones received exclusively GABA(A)ergic or both types of mIPSCs. In ot/ot animals, over 80 % of the neurones received exclusively GABA(A)R-mediated mIPSCs. GlyR-mediated mIPSC amplitude and charge were reduced in spa/spa and ot/ot animals. GABA,Rmediated mIPSC amplitude and charge were elevated in spa/spa but unaltered in ot/ot animals. GlyR- and GABA(A)R-mediated mIPSC decay times were similar for all genotypes, consistent with the mutations altering receptor numbers but not kinetics. These findings suggest the spastic and oscillator mutations, traditionally considered motor disturbances, also disrupt inhibition in a sensory region associated with nociceptive transmission. Furthermore, the spastic mutation results in a compensatory increase in GABA(A)ergic transmission in SFDH neurones, a form of inhibitory synaptic plasticity absent in the oscillator mouse.

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Colonial spiders evolved a differential prey-capture behaviour in concert with their venom chemistry, which may be a source of novel drugs. Some highly active tetrahydro-beta-carboline (TH beta C) toxins were recently isolated from the venom of the colonial spider Parawixia bistriata; the spiders use these toxins as part of their chemical arsenal to kill and/or paralyze preys. The major TH beta C compound isolated from this venom was identified as 6-hydroxytrypargine, also known as PwTX-I. Most natural compounds of animal origin occur in low abundance, and the natural abundance of PwTX-I is insufficient for complete functional characterization. Thus, PwTx-I was synthesized using a Pictet-Spengler condensation strategy, and the stereoisomers of the synthetic toxin were separated by chiral chromatography. The fraction of venom containing a mixture of three natural TH beta C toxins and enantiomers of PwTx-I were analyzed for inhibition of monoamine oxidase (MAO)-A and -B and for toxicity to insects. We reveal that the mixture of the natural TH beta C toxins, as well as the enantiomers of PwTx-I, were non-competitive inhibitors of MAO-A and MAO-B and caused potent paralysis of honeybees. The (-)-PwTX-I enantiomer is 2-fold more potent than the (+)-PwTX-I enantiomer in the assays performed. (C) 2009 Elsevier Ltd. All rights reserved.

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Although Bell`s palsy is the major cause of acute peripheral facial palsy, its pathogenesis remains unknown. Reactivation of the varicella zoster virus has been implicated as one of the main causes of Bell`s palsy, however, studies which investigate the varicella zoster virus reactivation in Bell`s palsy patients are mostly Japanese and, therefore, personal and geographic characteristics are quite different from our population. Aims: To determine varicella zoster virus frequency in saliva samples from patients with Bell`s palsy, using PCR. Material and Method: One hundred seventy one patients with acute peripheral facial palsy were prospectively enrolled in this study. One hundred twenty were clinically diagnosed with Bell`s palsy, within one week of onset of the disease and no previous anti-viral therapy. We had 20 healthy adults as controls. Three saliva samples were collected from patients and controls at initial examination and at one and two weeks later. The detection of the varicella zoster virus DNA was performed using PCR. Results: Varicella zoster virus was detected in two patients (1.7%). The virus was not identified in saliva samples from the controls. Conclusions: Varicella zoster virus was detected in 1.7% of saliva samples from patients with Bell`s palsy, using PCR.

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Some patients are no longer able to communicate effectively or even interact with the outside world in ways that most of us take for granted. In the most severe cases, tetraplegic or post-stroke patients are literally `locked in` their bodies, unable to exert any motor control after, for example, a spinal cord injury or a brainstem stroke, requiring alternative methods of communication and control. But we suggest that, in the near future, their brains may offer them a way out. Non-invasive electroencephalogram (EEG)-based brain-computer interfaces (BCD can be characterized by the technique used to measure brain activity and by the way that different brain signals are translated into commands that control an effector (e.g., controlling a computer cursor for word processing and accessing the internet). This review focuses on the basic concepts of EEG-based BC!, the main advances in communication, motor control restoration and the down-regulation of cortical activity, and the mirror neuron system (MNS) in the context of BCI. The latter appears to be relevant for clinical applications in the coming years, particularly for severely limited patients. Hypothetically, MNS could provide a robust way to map neural activity to behavior, representing the high-level information about goals and intentions of these patients. Non-invasive EEG-based BCIs allow brain-derived communication in patients with amyotrophic lateral sclerosis and motor control restoration in patients after spinal cord injury and stroke. Epilepsy and attention deficit and hyperactive disorder patients were able to down-regulate their cortical activity. Given the rapid progression of EEG-based BCI research over the last few years and the swift ascent of computer processing speeds and signal analysis techniques, we suggest that emerging ideas (e.g., MNS in the context of BC!) related to clinical neuro-rehabilitation of severely limited patients will generate viable clinical applications in the near future.

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OBJECTIVE: Phrenic nerve transfer has been used for treating lesions of the brachial plexus since 1970. Although, today, surgeons are more experienced with the technique, there are still widespread concerns about its effects on pulmonary function. This study was undertaken to evaluate the effectiveness and safety of this procedure. METHODS: Fourteen patients with complete palsy of the upper limb were submitted to phrenic nerve transfer as part of a strategy for surgical reconstruction of their plexuses. Two patients were lost to follow-up, and 2 patients were followed for less than 2 years. Of the remaining 10 patients, 9 (90%) were male. The lesions affected both sides equally. The mean age of the patients was 24.8 years (range, 14-43 years), and the mean interval from injury to surgery was 6 months (range, 3-9 months). The phrenic nerve was always transferred to the musculocutaneous nerve, and a nerve graft (mean length, 8 cm; range, 4.5-12 cm) was necessary in all cases. RESULTS: There was no major complication related to the surgery. Seven patients (70%) recovered functional level biceps strength (Medical Research Council grade >= 3). All of the patients exhibited a transient decrease in pulmonary function tests, but without clinical respiratory problems. CONCLUSION: On the basis of our small series and data from the literature, we conclude that phrenic nerve transfer in well-selected patients is a safe and effective procedure for recovering biceps function.

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OBJECTIVE: Hypoglossal-facial neurorrhaphy has been widely used for reanimation of paralyzed facial muscles after irreversible proximal injury of the facial nerve. However, complete section of the hypoglossal nerve occasionally results in hemiglossal dysfunction and interferes with swallowing and speech. To reduce this morbidity, a modified technique with partial section of the hypoglossal nerve after mastoid dissection of the facial nerve (HFM) has been used. We report our experience with the HFM technique, retrospectively comparing the outcome with results of the classic hypoglossal-facial neurorrhaphy. METHODS: A retrospective review was performed in 36 patients who underwent hypoglossal-facial neurorrhaphy with the classic (n = 12) or variant technique (n = 24) between 2000 and 2006. Facial Outcome was evaluated with the House-Brackmann grading system, and tongue function was evaluated with a new scale proposed to quantify Postoperative tongue alteration. The results were compared, and age and time between nerve injury and surgery were correlated with the outcome. RESULTS: There was no significant difference between the two techniques concerning facial reanimation. A worse outcome of tongue function, however, was associated with the classic technique (Mann-Whitney U test; P < 0.05). When HFM was used, significant correlations defined by the Spearman test were identified between preoperative delay (p = 0.59; P = 0.002) or age (p = 0.42; P = 0.031) and results of facial reanimation evaluated with the House-Brackmann grading system. CONCLUSION: HFM is as effective as classic hypoglossal-facial neurorrhaphy for facial reanimation, and it has a much lower morbidity related to tongue function. Better results are obtained in younger patients and with a shorter interval between facial nerve injury and surgery.

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Introduction. Spontaneous spinal epidural hematoma (SEH) represents 0.3-0.9% of spinal epidural space-occupying lesions, and most surgeons advocate aggressive and early surgical intervention. In. this paper we describe a patient with SEH with sudden paraplegia. Case report. This 30-year-old man had experienced one prior episode of sudden dorsal pain two days before the current admission and while he waited medical attendance, his legs suddenly became weak, and immediately afterwards, he became completely paraplegic in minutes. The patient had complete paraplegia, analgesia below the T4 level and urinary retention. He had no anticoagulant agent and no coagulopathic disease. He was submitted to computerized tomography that demonstrated a dorsally located epidural hematoma extending from the T3 to the T6 level with spinal cord compression. A laminectomy from T3 to T7 was performed four hours after the onset of the symptom. In postoperative time the patient presented the partial sensorial recovery and motor force grade II. The patient was directed to a neurorehabilitation program and in the last medical evaluation he presented recovery for motor grade III-IV without pain. Conclusion. The SHE is rare, with severe neurological consequences for patients and early surgical treatment persist as essential for motor recovery.

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Aims: We evaluated the effect of botulinum toxin type A (BTX-A) injections in the trigone on the antireflux mechanism and evaluated its short-term efficacy. Materials and Methods: Between April and December 2006, 21 patients (10 men and 11 women) were prospectively evaluated. All were incontinent due to refractory NDO and underwent detrusor injection of 300 units of BTX-A, including 50 units into the trigone. Baseline and postoperative evaluation after eight weeks included cystogram, urinary tract ultrasound and urodynamics. Results: At baseline, 20 patients had no vesicoureteral (VUR) and one had grade II unilateral VUR. Postoperative evaluation revealed no cases of de novo VUR and the patient with preinjection VUR had complete resolution of the reflux. Ultrasound showed 5 (23.8%) patients with hydronephrosis before BTX-A injection and only one (4.8%) at the followup evaluation (p=0.066). After treatment, 9 (42.8%) patients became dry, 11 (52.4%) were improved and one (4.8%) had no improvement. Improved patients received antimuscarinic treatment and 8 (38.1%) became dry, with a final total continence rate of 80.1%. Cystometric capacity increased from 271 +/- 92 to 390 +/- 1189 ml (p = 0.002), reflex volume varied from 241 +/- 96 to 323 +/- 201 ml (p = 0.020) and maximum detrusor pressure reduced from 66 +/- 39 to 38 +/- 37 cm H2O (p < 0.001). Conclusions: Our results confirm the safety of trigone injections of BTX-A in terms of development of VUR and upper urinary tract damage. Whether they are beneficial for patients with NDO or other causes of voiding dysfunction will need further studies.

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Objectives/Hypothesis: To analyze clinical and epidemiological features of neck nerve schwannomas, with emphasis on the neurologic outcome after surgical excision sparing as much of nerve fibers as possible with enucleation technique. Study Design: Retrospective study. Methods: Review of medical records from 1987 to 2006 of patients with neck nerve schwannomas, treated in a single institution. Results: Twenty-two patients were identified. Gender distribution was equal and age ranged from 15 to 61 years (mean: 38.6 years). Seven vagal, four brachial plexus, four sympathetic trunk, three cervical plexus, and two lesions on other sites could be identified. Most common symptom was neck mass. Local or irradiated pain also occurred in five cases. Median growing rate of tumors was 3 mm per year. Nerve paralysis was noted twice (a vagal schwannoma and a hypoglossal paralysis compressed by a vagal schwannoma). Different techniques were employed, and seven out of nine patients kept their nerve function (78%) after enucleation. No recurrence was observed in follow-up. Conclusions: Schwannomas should be treated surgically because of its growing potential, leading to local and neural compression symptoms. When possible, enucleation, which was employed in 10 patients of this series, is the recommended surgical option, allowing neural function preservation or restoration in most instances. This is especially important in the head and neck, where denervation may have a significant impact on the quality of life.