940 resultados para glottal closure
Resumo:
UNLABELLED Obstructive sleep apnea (OSA) is a frequent syndrome characterized by intermittent hypoxemia and increased prevalence of arterial hypertension and cardiovascular morbidity. In OSA, the presence of patent foramen ovale (PFO) is associated with increased number of apneas and more severe oxygen desaturation. We hypothesized that PFO closure improves sleep-disordered breathing and, in turn, has favorable effects on vascular function and arterial blood pressure. In 40 consecutive patients with newly diagnosed OSA, we searched for PFO. After initial cardiovascular assessment, the 14 patients with PFO underwent initial device closure and the 26 without PFO served as control group. Conventional treatment for OSA was postponed for 3 months in both groups, and polysomnographic and cardiovascular examinations were repeated at the end of the follow-up period. PFO closure significantly improved the apnea-hypopnea index (ΔAHI -7.9±10.4 versus +4.7±13.1 events/h, P=0.0009, PFO closure versus control), the oxygen desaturation index (ΔODI -7.6±16.6 versus +7.6±17.0 events/h, P=0.01), and the number of patients with severe OSA decreased significantly after PFO closure (79% versus 21%, P=0.007). The following cardiovascular parameters improved significantly in the PFO closure group, although remained unchanged in controls: brachial artery flow-mediated vasodilation, carotid artery stiffness, nocturnal systolic and diastolic blood pressure (-7 mm Hg, P=0.009 and -3 mm Hg, P=0.04, respectively), blood pressure dipping, and left ventricular diastolic function. In conclusion, PFO closure in OSA patients improves sleep-disordered breathing and nocturnal oxygenation. This translates into an improvement of endothelial function and vascular stiffening, a decrease of nighttime blood pressure, restoration of the dipping pattern, and improvement of left ventricular diastolic function. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01780207.
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OBJECTIVE The purpose of this study was to examine the recurrence rate of wound rupture in primary pilonidal sinus disease (PSD) after median closure. SUBJECTS AND METHODS A total of 583 patients from the German military cohort were interviewed. We compared the choice of surgical therapy, wound dehiscence (if present) and long-term recurrence-free survival for patients with primary open treatment, marsupialization and primary median treatment (closed vs. secondary open, respectively). Actuarial recurrence rate was determined using the Kaplan-Meier calculation with a follow-up of up to 20 years after primary PSD surgery. RESULTS Patients with excision followed by primary open wound treatment showed a significantly lower 5- than 10-year recurrence rate (8.3 vs. 11.2%) compared to the patients with primary midline closure (17.4 vs. 20.5%, p = 0.03). The 20-year recurrence rate was 28% in primary open wound treatment versus 44% in primary midline closure without wound rupture. In contrast to these findings, long-term recurrence rates following secondary open wound treatment (12.2% at 5 years vs. 17.1% at 10 years) tended to be higher (although not significantly, p = 0.57) compared to primary open treatment (8.3% at 5 years vs. 11.2% at 10 years). There was no statistical difference in long-term recurrence rates between secondary open and primary midline closure (p = 0.7). Hence, despite only a short wound closure time experienced before wound rupture, the patient does not fully benefit from an open wound treatment in terms of recurrence rate. CONCLUSION The postoperative pilonidal sinus wound rupture of primary midline closures did not significantly increase the 5- and 10-year long-term recurrence rates compared to uneventfully healing primary midline closures.
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Closure of the patent foramen ovale does not benefit from echocardiographic guidance in the majority of cases. Guiding these procedures with fluoroscopy only reduces procedure time, radiation exposure, and amount of contrast medium. There is a clear trend to abandon echocardiographic guidance for this procedure over time and with growing experience.
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Three groups of Atlantic salmon were kept at a constant temperature of 4, 10 and 14 °C. The adipose fins were removed; six fish/group were sampled at 11 subsequent time points post-clipping. Samples were prepared for histopathological examination to study the course of re-epithelization. A score sheet was developed to assess the regeneration of epidermal and dermal cell types. Wounds were covered by a thin epidermal layer between 4 and 6 h post-clipping at 10 and 14 °C. In contrast, wound closure was completed between 6 and 12 h in fish held at a constant temperature of 4 °C. By 18 h post-clipping, superficial cells, cuboidal cells, prismatic basal cells and mucous cells were discernible in all temperature groups, rapidly progressing towards normal epidermal structure and thickness. Within the observation period, only minor regeneration was found in the dermal layers. A positive correlation between water temperature and healing rates was established for the epidermis. The rapid wound closure rate, epidermal normalization and the absence of inflammatory reaction signs suggest that adipose fin clipping under anaesthesia constitutes a minimally invasive method that may be used to mark large numbers of salmon presmolts without compromising fish welfare.
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Histone acetylation plays an essential role in many DNA-related processes such as transcriptional regulation via modulation of chromatin structure. Many histone acetytransferases have been discovered and studied in the past few years, but the roles of different histone acetyltransferases (HAT) during mammalian development are not well defined at present. Gcn5 histone acetyltransferase is highly expressed until E16.5 during development. Previous studies in our lab using a constitutive null allele demonstrated that Gcn5 knock out mice are embryonic lethal, precluding the study of Gcn5 functions at later developmental stages. The creation of a conditional Gcn5 null allele, Gcn5flox allele, bypasses the early lethality. Mice homozygous for this allele are viable and appear healthy. In contrast, mice homozygous for a Gcn5 Δex3-18 allele created by Cre-loxP mediated deletion display a phenotype identical to our original Gcn5 null mice. Strikingly, a Gcn5flox(neo) allele, which contain a neomycin cassette in the second intron of Gcn5 is only partially functional and gives rise to a hypomorphic phenotype. Initiation of cranial neural tube closure at forebrain/midbrain boundary fails, resulting in an exencephaly in some Gcn5flox(neo)/flox(neo) embryos. These defects were found at an even greater penetrance in Gcn5flox(neo)/Δ embryos and become completely penetrant in the 129Sv genetic background, suggesting that Gcn5 controls mouse neural tube closure in a dose dependent manner. Furthermore, both Gcn5flox(neo)/flox(neo) and Gcn5 flox(neo)/Δ embryos exhibit anterior homeotic transformations in lower thoracic and lumbar vertebrae. These defects are accompanied by decreased expression levels and a shift in anterior expression boundary of Hoxc8 and Hoxc9. This study provides the first evidence that Gcn5 regulates Hox gene expression and is required for normal axial skeletal patterning in mice. ^
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Injury is an inevitable part of life, making wound healing essential for survival. In postembryonic skin, wound closure requires that epidermal cells recognize the presence of a gap and change their behavior to migrate across it. In Drosophila larvae, wound closure requires two signaling pathways (the Jun N-terminal kinase (JNK) pathway and the Pvr receptor tyrosine kinase signaling pathway) and regulation of the actin cytoskeleton. In this and other systems, it remains unclear how the signaling pathways that initiate wound closure connect to the actin regulators that help execute wound- induced cell migrations. Here we show that chickadee, which encodes the Drosophila Profilin, a protein important for actin filament recycling and cell migration during development, is required for the physiological process of larval epidermal wound closure. After injury, chickadee is transcriptionally upregulated in cells proximal to the wound. We found that JNK, but not Pvr, mediates the increase in chic transcription through the Jun and Fos transcription factors. Finally, we show that chic deficient larvae fail to form a robust actin cable along the wound edge and also fail to form normal filopodial and lamellipodial extensions into the wound gap. Our results thus connect a factor that regulates actin monomer recycling to the JNK signaling pathway during wound closure. They also reveal a physiological function for an important developmental regulator of actin and begin to tease out the logic of how the wound repair response is organized.
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OBJECTIVES We sought to assess the safety and efficacy of percutaneous closure of atrial septal defects (ASDs) under fluoroscopic guidance only, without periprocedural echocardiographic guidance. BACKGROUND Percutaneous closure of ASDs is usually performed using simultaneous fluoroscopic and transthoracic, transesophageal (TEE), or intracardiac echocardiographic (ICE) guidance. However, TEE requires deep sedation or general anesthesia, which considerably lengthens the procedure. TEE and ICE increase costs. METHODS Between 1997 and 2008, a total of 217 consecutive patients (age, 38 ± 22 years; 155 females and 62 males), of whom 44 were children ≤16 years, underwent percutaneous ASD closure with an Amplatzer ASD occluder (AASDO). TEE guidance and general anesthesia were restricted to the children, while devices were implanted under fluoroscopic guidance only in the adults. For comparison of technical safety and feasibility of the procedure without echocardiographic guidance, the children served as a control group. RESULTS The implantation procedure was successful in all but 3 patients (1 child and 2 adults; 1.4%). Mean device size was 23 ± 8 mm (range, 4-40 mm). There was 1 postprocedural complication (0.5%; transient perimyocarditis in an adult patient). At last echocardiographic follow-up, 13 ± 23 months after the procedure, 90% of patients had no residual shunt, whereas a minimal, moderate, or large shunt persisted in 7%, 1%, and 2%, respectively. Four adult patients (2%) underwent implantation of a second device for a residual shunt. During a mean follow-up period of 3 ± 2 years, 2 deaths and 1 ischemic stroke occurred. CONCLUSION According to these results, percutaneous ASD closure using the AASDO without periprocedural echocardiographic guidance seems safe and feasible.
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We provide explicit families of tame automorphisms of the complex affine three-space which degenerate to wild automorphisms. This shows that the tame subgroup of the group of polynomial automorphisms of C3 is not closed, when the latter is seen as an infinite-dimensional algebraic group.
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Voice biometry is classically based on the parameterization and patterning of speech features mainly. The present approach is based on the characterization of phonation features instead (glottal features). The intention is to reduce intra-speaker variability due to the `text'. Through the study of larynx biomechanics it may be seen that the glottal correlates constitute a family of 2-nd order gaussian wavelets. The methodology relies in the extraction of glottal correlates (the glottal source) which are parameterized using wavelet techniques. Classification and pattern matching was carried out using Gaussian Mixture Models. Data of speakers from a balanced database and NIST SRE HASR2 were used in verification experiments. Preliminary results are given and discussed.
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In order to obtain more human like sounding humanmachine interfaces we must first be able to give them expressive capabilities in the way of emotional and stylistic features so as to closely adequate them to the intended task. If we want to replicate those features it is not enough to merely replicate the prosodic information of fundamental frequency and speaking rhythm. The proposed additional layer is the modification of the glottal model, for which we make use of the GlottHMM parameters. This paper analyzes the viability of such an approach by verifying that the expressive nuances are captured by the aforementioned features, obtaining 95% recognition rates on styled speaking and 82% on emotional speech. Then we evaluate the effect of speaker bias and recording environment on the source modeling in order to quantify possible problems when analyzing multi-speaker databases. Finally we propose a speaking styles separation for Spanish based on prosodic features and check its perceptual significance.
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This paper presents a description of our system for the Albayzin 2012 LRE competition. One of the main characteristics of this evaluation was the reduced number of available files for training the system, especially for the empty condition where no training data set was provided but only a development set. In addition, the whole database was created from online videos and around one third of the training data was labeled as noisy files. Our primary system was the fusion of three different i-vector based systems: one acoustic system based on MFCCs, a phonotactic system using trigrams of phone-posteriorgram counts, and another acoustic system based on RPLPs that improved robustness against noise. A contrastive system that included new features based on the glottal source was also presented. Official and postevaluation results for all the conditions using the proposed metrics for the evaluation and the Cavg metric are presented in the paper.