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1.
Inorg Chem ; 62(30): 12027-12037, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37466301

RESUMO

A new reduced phase derived from the excitonic insulator candidate Ta2NiSe5 has been synthesized via the intercalation of lithium. LiTa2NiSe5 crystallizes in the orthorhombic space group Pmnb (no. 62) with lattice parameters a = 3.50247(3) Å, b = 13.4053(4) Å, c = 15.7396(2) Å, and Z = 4, with an increase of the unit cell volume by 5.44(1)% compared with Ta2NiSe5. Significant rearrangement of the Ta-Ni-Se layers is observed, in particular a very significant relative displacement of the layers compared to the parent phase, similar to that which occurs under hydrostatic pressure. Neutron powder diffraction experiments and computational analysis confirm that Li occupies a distorted triangular prismatic site formed by Se atoms of adjacent Ta2NiSe5 layers with an average Li-Se bond length of 2.724(2) Å. Li-NMR experiments show a single Li environment at ambient temperature. Intercalation suppresses the distortion to monoclinic symmetry that occurs in Ta2NiSe5 at 328 K and that is believed to be driven by the formation of an excitonic insulating state. Magnetometry data show that the reduced phase has a smaller net diamagnetic susceptibility than Ta2NiSe5 due to the enhancement of the temperature-independent Pauli paramagnetism caused by the increased density of states at the Fermi level evident also from the calculations, consistent with the injection of electrons during intercalation and formation of a metallic phase.

2.
Eur J Prosthodont Restor Dent ; 25(4): 186-192, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29182214

RESUMO

OBJECTIVE: To assess the trueness and precision of copy denture templates produced using traditional methods and 3D printing. MATERIAL AND METHODS: Six copies of a denture were made using: 1. Conventional technique with silicone putty in an impression tray (CT). 2. Conventional technique with no impression tray (CNT). 3. 3D scanning and printing (3D). Scan trueness and precision was investigated by scanning a denture six times and comparing five scans to the sixth. Then the scans of the six CT, CNT and 3D dentures were compared by aligning, in turn, the copies of each denture to the scanned original. Outcome measures were the mean surface-to-surface distance, standard deviation of that distance and the maximum distance. Student's unpaired t-tests with Bonferroni correction were used to analyse the results. RESULTS: The repeated scans of the original denture showed a scan trueness of 0.013mm (SD 0.002) and precision of 0.013mm (SD 0.002). Trueness: CT templates, 0.168mm (0.047), CNT templates 0.195mm (0.034) and 3D 0.103mm (0.021). Precision: CT templates 0.158mm (0.037), CNT 0.233mm (0.073), 3D 0.090mm (0.017). For each outcome measure the 3D templates demonstrated an improvement which was statistically significant (p⟨0.05). CONCLUSIONS: 3D printed copy denture templates reproduced the original with greater trueness and precision than conventional techniques.


Assuntos
Técnica de Moldagem Odontológica , Prótese Total , Impressão Tridimensional , Desenho Assistido por Computador , Humanos , Imageamento Tridimensional , Reprodutibilidade dos Testes
3.
Br J Sports Med ; 51(8): 677-685, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27986761

RESUMO

OBJECTIVES: The primary purpose of this systematic review is to examine the extant resistance training (RT) cancer research to evaluate the proportion of RT interventions that: (1) implemented key RT training principles (specificity, progression, overload) and (2) explicitly reported relevant RT prescription components (frequency, intensity, sets, reps). DESIGN: A qualitative systematic review was performed by two reviewers (CMF and PNH) who inspected the titles and abstracts to determine eligibility for this systematic review. Identified papers were obtained in full and further reviewed. Data were extracted to evaluate the application of principles of training, along with specific RT components. DATA SOURCES: Electronic databases (PubMed, EMBASE, CINAHL, Cochrane, PEDro, PsychInfo, Cancer Lit, Sport Discus, AMED, Cochrane Central Register of Controlled Trials) and reference lists of included articles from inception to May 2016. RESULTS: 37 studies were included. The principle of specificity was used appropriately in all of the studies, progression in 65% and overload in 76% of the studies. The most common exercise prescription (∼50%) implemented in the studies included in this review were 2-3 days/week, focusing on large muscle groups, 60-70% 1 repetition maximum (RM), 1-3 sets of 8-12 repetitions. CONCLUSIONS: Reporting of RT principles in an oncology setting varies greatly, with often vague or non-existent references to the principles of training and how the RT prescription was designed.


Assuntos
Terapia por Exercício/métodos , Neoplasias/terapia , Treinamento Resistido/métodos , Humanos , Prescrições , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Arch Dis Child ; 101(10): 929-34, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27449674

RESUMO

OBJECTIVE: Indicators for head CT scan defined by the 2007 National Institute for Health and Care Excellence (NICE) guidelines were analysed to identify CT uptake, influential variables and yield. DESIGN: Cross-sectional study. SETTING: Hospital inpatient units: England, Wales, Northern Ireland and the Channel Islands. PATIENTS: Children (<15 years) admitted to hospital for more than 4 h following a head injury (September 2009 to February 2010). INTERVENTIONS: CT scan. MAIN OUTCOME MEASURES: Number of children who had CT, extent to which NICE guidelines were followed and diagnostic yield. RESULTS: Data on 5700 children were returned by 90% of eligible hospitals, 84% of whom were admitted to a general hospital. CT scans were performed on 30.4% of children (1734), with a higher diagnostic yield in infants (56.5% (144/255)) than children aged 1 to 14 years (26.5% (391/1476)). Overall, only 40.4% (984 of 2437 children) fulfilling at least one of the four NICE criteria for CT actually underwent one. These children were much less likely to receive CT if admitted to a general hospital than to a specialist centre (OR 0.52 (95% CI 0.45 to 0.59)); there was considerable variation between healthcare regions. When indicated, children >3 years were much more likely to have CT than those <3 years (OR 2.35 (95% CI 2.08 to 2.65)). CONCLUSION: Compliance with guidelines and diagnostic yield was variable across age groups, the type of hospital and region where children were admitted. With this pattern of clinical practice the risks of both missing intracranial injury and overuse of CT are considerable.


Assuntos
Traumatismos Craniocerebrais/diagnóstico por imagem , Seleção de Pacientes , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Acidentes por Quedas/estatística & dados numéricos , Acidentes Domésticos , Acidentes de Trânsito/estatística & dados numéricos , Adolescente , Distribuição por Idade , Criança , Pré-Escolar , Traumatismos Craniocerebrais/epidemiologia , Traumatismos Craniocerebrais/etiologia , Procedimentos Clínicos , Estudos Transversais , Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Prevalência , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/epidemiologia , Tempo para o Tratamento , Resultado do Tratamento , Inconsciência/diagnóstico por imagem , Inconsciência/epidemiologia , Reino Unido/epidemiologia , Procedimentos Desnecessários/estatística & dados numéricos
5.
Proc Inst Mech Eng H ; 230(5): 481-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27160565

RESUMO

Metal-on-polyethylene total disc replacements have been an alternative to spinal fusion in the lumbar spine under certain indications for more than a decade. Recently, cervical total disc replacement has also become an alternative to cervical fusion. Knowledge acquired from years of in vitro simulator studies on other joint replacements has highlighted the risks associated with premature wear due to unforeseen adverse clinical conditions and the effect of particulate debris on surrounding natural tissues. Having no evidence of the type and composition of the lubricating fluid that will result after spinal arthroplasty, a study on the effects of lubricant serum concentration was undertaken. The wear rate was shown to be inversely proportional to protein content of the serum over a range of 50%-3% bovine serum to water concentration.


Assuntos
Análise de Falha de Equipamento/métodos , Lubrificantes/química , Metais Pesados/química , Polietileno/química , Substituição Total de Disco/instrumentação , Animais , Bovinos , Vértebras Cervicais/cirurgia , Simulação por Computador , Próteses e Implantes , Soro/química
6.
Arch Dis Child ; 101(6): 527-532, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26998632

RESUMO

BACKGROUND: The National Confidential Enquiry describes the epidemiology of children admitted to hospital with head injury. METHOD: Children (<15 years old) who died or were admitted for >4 h with head injury were identified from 216 UK hospitals (1 September 2009 to 28 February 2010). Data were collected using standard proformas and entered on to a database. A descriptive analysis of the causal mechanisms, child demographics, neurological impairment, CT findings, and outcome at 72 h are provided. RESULTS: Details of 5700 children, median age 4 years (range 0-14.9 years), were analysed; 1093 (19.2%) were <1 year old, 3500 (61.4%) were boys. There was a significant association of head injury with social deprivation 39.7/100 000 (95% CI 37.0 to 42.6) in the least deprived first quintile vs. 55.1 (95% CI 52.1 to 58.2) in the most deprived fifth quintile (p<0.01). Twenty-four children died (0.4%). Most children were admitted for one night or less; 4522 (79%) had a Glasgow Coma Scale score of 15 or were Alert (on AVPU (Alert, Voice, Pain, Unresponsive)). The most common causes of head injury were falls (3537 (62.1%); children <5 years), sports-related incidents (783 (13.7%); median age 12.4 years), or motor vehicle accidents (MVAs) (401 (7.1%); primary-school-aged children). CT scans were performed in 1734 (30.4%) children; 536 (30.9%) were abnormal (skull fracture and/or intracranial injury or abnormality): 269 (7.6%) were falls, 82 (10.5%) sports related and 100 (25%). A total of 357 (6.2%) children were referred to social care because of child protection concerns (median age 9 months (range 0-14.9 years)). CONCLUSIONS: The data described highlight priorities for targeted age-specific head injury prevention and have the potential to provide a baseline to evaluate the effects of regional trauma networks (2012) and National Institute of Health and Care Excellence (NICE) head injury guidelines (2014), which were revised after the study was completed.


Assuntos
Traumatismos Craniocerebrais/epidemiologia , Acidentes por Quedas/estatística & dados numéricos , Acidentes de Trânsito/estatística & dados numéricos , Adolescente , Distribuição por Idade , Traumatismos em Atletas/epidemiologia , Criança , Serviços de Proteção Infantil/estatística & dados numéricos , Pré-Escolar , Traumatismos Craniocerebrais/diagnóstico por imagem , Traumatismos Craniocerebrais/mortalidade , Feminino , Escala de Coma de Glasgow , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Tempo de Internação/estatística & dados numéricos , Masculino , Prevalência , Estudos Prospectivos , Índice de Gravidade de Doença , Distribuição por Sexo , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/epidemiologia , Fraturas Cranianas/mortalidade , Fatores Socioeconômicos , Tomografia Computadorizada por Raios X , Reino Unido/epidemiologia
7.
Arch Dis Child ; 100(11): 1032-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26297697

RESUMO

UNLABELLED: The risk of serious head injury (HI) from a fall in a young child is ill defined. The relationship between the object fallen from and prevalence of intracranial injury (ICI) or skull fracture is described. METHOD: Cross-sectional study of HIs from falls in children (<6 years) admitted to UK hospitals, analysed according to the object fallen from and associated Glasgow Coma Score (GCS) or alert, voice, pain, unresponsive (AVPU) and CT scan results. RESULTS: Of 1775 cases ascertained (median age 18 months, 54.7% boys), 87% (1552) had a GCS=15/AVPU=alert. 19.3% (342) had a CT scan: 32% (110/342) were abnormal; equivalent to 5.9% of the overall population, 16.9% (58) had isolated skull fractures and 13.7% (47) had ICI (49% (23/47) had an associated skull fracture). The prevalence of ICI increased with neurological compromise; however, 12% of children with a GCS=15/AVPU=alert had ICI. When compared to falls from standing, falls from a person's arms (233 children (mean age 1 year)) had a significant relative OR for a skull fracture/ICI of 6.94 (95% CI 3.54 to 13.6), falls from a building (eg, window or attic) (mean age 3 years) OR 6.84 (95% CI 2.65 to 17.6) and from an infant or child product (mean age 21 months) OR 2.75 (95% CI 1.36 to 5.65). CONCLUSIONS: Most HIs from a fall in these children admitted to hospital were minor. Infants, dropped from a carer's arms, those who fell from infant products, a window, wall or from an attic had the greatest chance of ICI or skull fracture. These data inform prevention and the assessment of the likelihood of serious injury when the object fallen from is known.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Traumatismos Craniocerebrais/epidemiologia , Distribuição por Idade , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/epidemiologia , Lesões Encefálicas/etiologia , Pré-Escolar , Traumatismos Craniocerebrais/diagnóstico por imagem , Traumatismos Craniocerebrais/etiologia , Estudos Transversais , Feminino , Escala de Coma de Glasgow , Humanos , Lactente , Masculino , Índice de Gravidade de Doença , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/epidemiologia , Fraturas Cranianas/etiologia , Tomografia Computadorizada por Raios X , Reino Unido/epidemiologia
8.
J Mech Behav Biomed Mater ; 44: 43-52, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25598071

RESUMO

Development of pre-clinical testing methodologies is an important goal for improving prediction of artificial replacement joint performance and for guiding future device design. Total disc replacement wear and the potential for osteolysis is a growing concern, therefore a parametric study on the effects on wear of altered kinematics and loading was undertaken. A standard ISO testing protocol was modified in order to study the wear behaviour of lumbar total disc replacements when subject to low cross shear input kinematics, reduced axial loading and smaller flexion-extension magnitude. Volumetric wear, bearing surface topography, and wear debris biological reactivity were assessed. The ISO standard results were expected, however, the very low cross shear test produced a level of wear approximately two orders of magnitude higher than that reported for zero cross shear motions on UHMWPE bearings. When the osteolytic potential of the wear particles was calculated, all total disc replacement simulations had lower predicted osteolytic potential compared to total hip replacements, as a consequence of the generally lower wear rates found.


Assuntos
Teste de Materiais/normas , Fenômenos Mecânicos , Substituição Total de Disco , Movimento (Física) , Tamanho da Partícula , Padrões de Referência , Suporte de Carga
9.
J Perinatol ; 34(11): 873-4, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25359413

RESUMO

Intrauterine infection with herpes simplex virus, although very rare, has devastating effects on multiple organ systems in the fetus and can lead to in utero fetal demise. Neonates born following intrauterine herpes simplex virus infection commonly manifest with cutaneous lesions, ocular damage and/or brain abnormalities. We describe the case of a dichorionic, diamniotic twin gestation complicated by intrauterine herpes simplex virus infection. This infection led to the fetal demise of twin A and a very uncommon presentation of limb hypoplasia in twin B.


Assuntos
Braço/anormalidades , Doenças em Gêmeos/congênito , Herpes Simples/complicações , Herpesvirus Humano 2 , Complicações Infecciosas na Gravidez , Deformidades Congênitas das Extremidades Superiores/virologia , Corioamnionite/virologia , Doenças em Gêmeos/virologia , Feminino , Morte Fetal , Retardo do Crescimento Fetal , Humanos , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Lactente Extremamente Prematuro , Recém-Nascido , Gravidez , Resultado da Gravidez , Adulto Jovem
10.
Phys Rev Lett ; 111(21): 217602, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313526

RESUMO

We develop a method for universally resolving the important issue of separating spin pumping from spin rectification signals in bilayer spintronics devices. This method is based on the characteristic distinction of spin pumping and spin rectification, as revealed in their different angular and field symmetries. It applies generally for analyzing charge voltages in bilayers induced by the ferromagnetic resonance (FMR), independent of FMR line shape. Hence, it solves the outstanding problem that device-specific microwave properties restrict the universal quantification of the spin Hall angle in bilayer devices via FMR experiments. Furthermore, it paves the way for directly measuring the nonlinear evolution of spin current generated by spin pumping. The spin Hall angle in a Py/Pt bilayer is thereby directly measured as 0.021±0.015 up to a large precession cone angle of about 20°.

11.
Environ Pollut ; 163: 62-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22325432

RESUMO

Deterministic photochemical air quality models are commonly used for regulatory management and planning of urban airsheds. These models are complex, computer intensive, and hence are prohibitively expensive for routine air quality predictions. Stochastic methods are becoming increasingly popular as an alternative, which relegate decision making to artificial intelligence based on Neural Networks that are made of artificial neurons or 'nodes' capable of 'learning through training' via historic data. A Neural Network was used to predict particulate matter concentration at a regulatory monitoring site in Phoenix, Arizona; its development, efficacy as a predictive tool and performance vis-à-vis a commonly used regulatory photochemical model are described in this paper. It is concluded that Neural Networks are much easier, quicker and economical to implement without compromising the accuracy of predictions. Neural Networks can be used to develop rapid air quality warning systems based on a network of automated monitoring stations.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Modelos Químicos , Redes Neurais de Computação , Material Particulado/análise , Atmosfera/química , Cidades , Previsões , Tamanho da Partícula , Estatística como Assunto
12.
Eur Spine J ; 19(8): 1356-62, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20401672

RESUMO

The current wear-testing standard (ISO18192-1) for total disc replacement (TDR) requires only four degrees of freedom (DOF) inputs: axial load, flexion-extension, lateral bending and axial rotation. The study aim was to assess the effect of an additional DOF, anterior-posterior (AP) shear on the wear of the ProDisc-L TDR. A 5DOF simulator was used to test ProDisc-L implants under 4DOF and 5DOF conditions. The 4DOF conditions were defined by ISO18192-1 whilst the 5DOF used ISO18192-1 conditions with the addition of an AP load of +175 and -140 N (anterior and posterior, respectively), extrapolated from in vivo data. The implants were mounted such that the polyethylene insert could be removed for gravimetric measurements. Tests were run using bovine serum (15 g/l protein concentration) as a lubricant for five million cycles (MC), with measurements repeated every 1 MC. The mean wear rate in the 4DOF test was 12.7 +/- 2.1 mg/MC compared to 11.6 +/- 1.2 mg/MC in the 5DOF test. There were marked differences in the wear scars between 4DOF and 5DOF simulations. With 4DOF, wear scars were centralised on the dome of the insert, whilst 5DOF scars were larger, breaching the anterior rim of the dome causing deformation at the edge. The 4DOF wear test showed similar gravimetric wear rates to previously published ISO-tested TDRs. The addition of AP load was found to have no significant effect on the overall wear rate. However, there were pronounced differences in the respective wear scars, which highlights the need for more research in order to understand the factors that influence wear of TDR.


Assuntos
Disco Intervertebral/cirurgia , Teste de Materiais , Próteses e Implantes , Desenho de Prótese , Análise de Variância , Polietileno , Amplitude de Movimento Articular , Suporte de Carga
13.
Psychiatr Serv ; 52(12): 1591-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11726748

RESUMO

The authors describe the policy and administrative-practice implications of implementing evidence-based services, particularly in public-sector settings. They review the observations of the contributors to the evidence-based practices series published throughout 2001 in Psychiatric Services. Quality and accountability have become the watchwords of health and mental health services; evidence-based practices are a means to both ends. If the objective of accountable, high-quality services is to be achieved by implementing evidence-based practices, the right incentives must be put in place, and systemic barriers must be overcome. The authors use the framework from the U.S. Surgeon General's 1999 report on mental health to describe eight courses of action for addressing the gap between science and practice: continue to build the science base; overcome stigma; improve public awareness of effective treatments; ensure the supply of mental health services and providers; ensure delivery of state-of-the-art treatments; tailor treatment to age, sex, race, and culture; facilitate entry into treatment; and reduce financial barriers to treatment.


Assuntos
Medicina Baseada em Evidências , Política de Saúde , Serviços de Saúde Mental/normas , Política Pública , Qualidade da Assistência à Saúde , Etnicidade/psicologia , Humanos , Transtornos Mentais/terapia
14.
J Neurosci ; 21(21): 8586-93, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11606646

RESUMO

Maps of auditory space in the midbrain of the barn owl (Tyto alba) are calibrated by visual experience. When owls are raised wearing prismatic spectacles that displace the visual field in azimuth, the auditory receptive fields of neurons in the optic tectum shift to compensate for the optical displacement of the visual field. This shift results primarily from a shift in the tuning of tectal neurons for interaural time difference. The visually based instructive signal that guides this plasticity could be based on a topographic, point-by-point comparison between auditory and visual space maps or on a foveation-dependent visual assessment of the accuracy of auditory orienting responses. To distinguish between these two possibilities, we subjected owls to optical conditions that differed in the center of gaze and the visual periphery. A topographic signal would cause the portions of the space map representing the central and peripheral regions of visual space to adjust differently, according to the optical conditions that exist in each region. In contrast, a foveation-based signal would cause both portions of the map to adjust similarly, according to the optical conditions that exist at the center of gaze. In six of seven experiments, adaptive changes were as predicted by a topographic instructive signal. Although the results do not rule out the possible contribution of a foveation-based signal, they demonstrate that a topographic instructive signal is, indeed, involved in the calibration of the auditory space map in the barn owl optic tectum.


Assuntos
Vias Auditivas/fisiologia , Plasticidade Neuronal/fisiologia , Localização de Som/fisiologia , Percepção Espacial/fisiologia , Colículos Superiores/fisiologia , Adaptação Fisiológica/fisiologia , Animais , Vias Auditivas/citologia , Mapeamento Encefálico/métodos , Óculos , Fixação Ocular/fisiologia , Aprendizagem/fisiologia , Estimulação Luminosa/métodos , Privação Sensorial/fisiologia , Estrigiformes , Colículos Superiores/citologia , Visão Binocular/fisiologia , Campos Visuais/fisiologia
15.
Psychiatr Serv ; 52(9): 1198-205, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11533393

RESUMO

Outpatient commitment, although often viewed as merely an extension of inpatient commitment, is only one of a growing array of legal tools used to mandate treatment adherence. The authors describe various forms of mandated community treatment. People with severe and chronic mental disorders often depend on goods and services provided by the social welfare system. Benefits disbursed by representative payees and the provision of subsidized housing have both been used as leverage to ensure treatment adherence. Many discharged patients are arrested for criminal offenses. Favorable disposition of their cases by a mental health court may be tied to participation in treatment. Under outpatient commitment statutes, judges can order committed patients to comply with prescribed treatment. Patients may attempt to maximize their control over treatment in the event of later deterioration by executing an advance directive. The ideological posturing that currently characterizes the field must be replaced by an evidence-based approach.


Assuntos
Assistência Ambulatorial/organização & administração , Internação Compulsória de Doente Mental/legislação & jurisprudência , Serviços Comunitários de Saúde Mental/legislação & jurisprudência , Cooperação do Paciente , Diretivas Antecipadas , Serviços Comunitários de Saúde Mental/organização & administração , Humanos , Motivação , Avaliação de Resultados em Cuidados de Saúde , Assistência Pública , Estados Unidos
16.
Sleep Breath ; 5(2): 71-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11868144

RESUMO

The objective of this study was to assess whether cervical positioning could improve mild to moderate cases of the obstructive sleep apnea syndrome (OSAS). Eighteen subjects recruited from a tertiary sleep disorders clinic population with mild to moderate cases of OSAS were evaluated using a custom-fitted cervical pillow designed to increase upper airway caliber by promoting head extension. The subjects used their usual pillows during two consecutive recorded baseline nights in our laboratory. They then used the cervical pillow for 5 days at home and returned for 2 consecutive recorded nights at our laboratory to use the cervical pillow. During the nights in our laboratory, the subjects completed questionnaires, were videotaped to record head and body position, and had full polysomnography. The subjects had a significant trend toward improvement in their respiratory disturbance indices with use of the cervical pillow, despite spending more time in the supine position and having similar amounts of REM sleep in the baseline and experimental conditions. They also had nonsignificant trends toward improvements in their sleep efficiency and subjective depth of their sleep as well as significantly fewer arousals and awakenings in the experimental compared with the baseline condition. We propose that cervical positioning (i.e., head extension) with a custom-fitted cervical pillow provides a simple, noninvasive, and comfortable means of reducing sleep-disordered breathing in patients with mild to moderate OSAS.


Assuntos
Pescoço , Postura , Síndromes da Apneia do Sono/prevenção & controle , Apneia Obstrutiva do Sono/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Síndromes da Apneia do Sono/complicações , Síndromes da Apneia do Sono/diagnóstico , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico , Fases do Sono/fisiologia
17.
Glycobiology ; 10(11): 1183-92, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11087710

RESUMO

The interaction of heparan sulfate (HS) (and the closely related molecule heparin) with FGF-1 is a requirement for enabling the growth factor to activate its cell surface tyrosine kinase receptor. However, little is known about the regulatory role of naturally occurring cell surface HS in FGF-1 activation. We have addressed this issue by utilizing a library of HS oligosaccharides, which are defined in both length and sulfate content. Mitogenic activation assays using these oligosaccharides showed that HS contained both FGF-1 activatory and inhibitory sugar sequences. Further analysis of these oligosaccharides showed a clear correlation between FGF-1 promoting activity and their 6-O-sulfate content. The results, in particular with the dodecasaccharide sequences, suggested that specific positioning of 6-O-sulfate groups may be required for the promotion of FGF-1 mitogenic activity. This may also be true for 2-O-sulfate groups though the evidence was not as conclusive. Differential activation of FGF-1 and FGF-2 was also observed and found to be mediated by both oligosaccharide length and sulfation pattern, with different specific O-sulfate positioning being implicated for the promotion of different growth factors. These results suggest that variation and tight control of the fine structure of HS may allow cells to not only control their positive/negative responses to individual FGFs but also to change specificity towards promotion of different members of the FGF family.


Assuntos
Fator 2 de Crescimento de Fibroblastos/farmacologia , Fatores de Crescimento de Fibroblastos/farmacologia , Heparitina Sulfato/química , Heparitina Sulfato/farmacologia , Mitógenos/farmacologia , Oligossacarídeos/química , Oligossacarídeos/farmacologia , Animais , Sequência de Carboidratos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Fator 1 de Crescimento de Fibroblastos , Camundongos , Dados de Sequência Molecular , Relação Estrutura-Atividade
18.
J Comp Neurol ; 421(2): 146-60, 2000 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-10813778

RESUMO

In the barn owl (Tyto alba), the external nucleus of the inferior colliculus (ICX) contains a map of auditory space that is calibrated by visual experience. The source of the visually based instructive signal to the ICX is unknown. Injections of biotinylated dextran amine and Fluoro-Gold in the ICX retrogradely labelled neurons in layers 8-15 of the ipsilateral optic tectum (OT) that could carry this instructive signal. This projection was point-to-point and in register with the feed-forward, auditory projection from the ICX to the OT. Most labelled neurons were in layers 10-11, and most were bipolar. Tripolar, multipolar, and unipolar neurons were also observed. Multipolar neurons had dendrites that were oriented parallel to the tectal laminae. In contrast, most labelled bipolar and tripolar neurons had dendrites oriented perpendicular to the tectal laminae, extending superficially into the retino-recipient laminae and deep into the auditory recipient laminae. Therefore, these neurons were positioned to receive both visual and auditory information from particular locations in space. Biocytin injected into the superficial layers of the OT labelled bouton-laden axons in the ICX. These axons were generally finer than, but had similar bouton densities as, feed-forward auditory fibers in the ICX, labelled by injections of biocytin into the central nucleus of the inferior colliculus (ICC). These data demonstrate a point-to-point projection from the OT to the ICX that could provide a spatial template for calibrating the auditory space map in the ICX.


Assuntos
Vias Auditivas/fisiologia , Colículos Inferiores/fisiologia , Neurônios/fisiologia , Estrigiformes/anatomia & histologia , Colículos Superiores/fisiologia , Animais , Biotina/análogos & derivados , Dextranos , Corantes Fluorescentes , Vias Neurais/fisiologia
19.
J Rheumatol ; 27(2): 504-6, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10685821

RESUMO

We describe a preadolescent girl with intense ankle synovitis and pitting edema that obscured the subcutaneous origin of the inflammation. Typical nodular disease emerged after corticosteroid tapering when regional atrophy developed.


Assuntos
Artrite/diagnóstico , Paniculite/diagnóstico , Tecido Adiposo/patologia , Artrite/fisiopatologia , Atrofia , Criança , Diagnóstico Diferencial , Edema , Feminino , Humanos , Paniculite/patologia , Paniculite/fisiopatologia
20.
J Invest Dermatol ; 114(2): 381-7, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10652002

RESUMO

Epidermolysis bullosa (EB) with late-onset muscular dystrophy (EB-MD) is a hemidesmosomal variant of EB due to mutations in the plectin gene (PLEC1). The age of onset of muscle involvement has been noted to vary from infancy to the fourth decade of life. Immunofluorescence of the patients' skin and muscle biopsies is usually negative for staining with antibodies recognizing plectin, a large cytoskeleton-associated anchorage protein. In this study we report novel plectin mutations in two families with EB. In both families, the proband was a newborn with neonatal blistering with no evidence for muscle weakness as yet. Peripheral blood DNA was isolated and examined by heteroduplex scanning strategy, protein truncation test (PTT), and/or direct sequencing of the plectin gene. One of the probands was compound heterozygote for nonsense mutations E2005X/K4460X, and the proband in the second family was compound heterozygote for deletion mutations 5083delG/2745-9del21, the latter mutation extending from -9 to +12 at the intron 22/exon 23 border. The mutations K4460X and 5083delG were not present in either one of the parents, thus being de novo events. In both cases, nonpaternity was excluded by microsatellite marker analysis. The stop codon mutations are predicted to result in the synthesis of a truncated protein lacking the carboxy-terminal globular domain of the protein and possibly causing nonsense-mediated decay of the corresponding mRNA. The 2745-9del21 deletion mutation abolishes the splice site at the intron 22/exon 23 junction, predicting abnormal splicing events. Because plectin deficiency is associated with muscular dystrophy, molecular diagnostics of the plectin gene provides prognostic value in evaluation of these patients who appear to be at risk to develop muscular dystrophy.


Assuntos
Epidermólise Bolhosa , Adulto , Criança , Pré-Escolar , Códon , Epidermólise Bolhosa/genética , Saúde da Família , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Lactente , Proteínas de Filamentos Intermediários/genética , Masculino , Pessoa de Meia-Idade , Distrofias Musculares/genética , Plectina , Mutação Puntual
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