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91.
Masters IB Eastburn MM Wootton R Ware RS Francis PW Zimmerman PV Chang AB 《Thorax》2005,60(8):652-658
BACKGROUND: Accurate measurements of airway and lesion dimensions are important to the developmental progress of paediatric bronchoscopy. The malacia disorders are an important cause of respiratory morbidity in children, but no methods are currently available to measure these lesions or the airway lumen accurately. A new measurement technique is described here. METHODS: The magnification power of a paediatric videobronchoscope was defined and a simple and user friendly computer based program (Image J) was used to develop an objective technique (colour histogram mode technique, CHMT) for measurement of the airway lumen. RESULTS: In vivo intra-observer and inter-observer repeatability coefficients for repeated area measurements from 28 images using the Bland-Altman method were 0.9 mm2 and 1.6 mm2, respectively. The average intraclass correlation coefficient for repeated measurements of area was 0.93. In vitro validation measurements using a 2 mm diameter tube resolved radii measurements to within 0.1 mm (coefficient of variability 8%). An "acceptable result" was defined in 92% of 734 images completed with the CHMT alone and 8% with its modification. The success rate for two of three images being within 10% of each other's area was 100%. Measurements of cricoid cross sectional areas from 116 patients compared with expected airway areas for age derived from endotracheal tube sizes were comparable. CONCLUSIONS: The CHMT method of identifying and measuring airway dimensions is objective, accurate, and versatile and, as such, is important to the future development of flexible videobronchoscopy. 相似文献
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The pathogenesis of hydrocephalus following reovirus type 1 inoculation of neonatal mice has been examined by light microscopy, radiology, immunofluorescence, and electron microscopy. The reovirus infection causes an acute ependymitis and leptomeningitis, followed by a fibrous arachnoiditis and arachnoid villitis. Hydrocephalus develops in proportion to the degree of inflammatory/fibrotic changes within the cerebrospinal fluid pathways. With the beginning of hydrocephalus there is radiographic evidence of basal cistern blockage. As the hydrocephalic state progresses, axial herniation and compression of the midbrain result in the appearance of aqueduct stenosis. We demonstrate that the stenosis of the aqueduct is a secondary phenomenon, not causally related to the pathogenesis of hydrocephalus, and discuss the significance of this finding to human aqueduct stenosis. 相似文献
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97.
Yarovaya N Schot R Fodero L McMahon M Mahoney A Williams R Verbeek E de Bondt A Hampson M van der Spek P Stubbs A Masters CL Verheijen FW Mancini GM Venter DJ 《Neurobiology of disease》2005,19(3):351-365
Sialin is a lysosomal membrane protein encoded by the SLC17A5 gene, which is mutated in patients with sialic acid storage diseases (SASD). To further understand the role of sialin in normal CNS development and in the progressive neuronal atrophy and dysmyelination seen in SASD, we investigated its normal cellular distribution in adult and developing mice. Overall, sialin showed granular immunoreactivity, consistent with a vesicular protein. Adult mice showed widespread sialin expression, including in the brain, heart, lung, and liver. High-level immunoreactivity was seen in the neuropil of the hippocampus, striatum, and cerebral cortex, as well as in the perikarya of cerebellar Purkinje cells, globus pallidus, and certain thalamic and brainstem nuclei. In mouse embryos, the highest levels of expression were observed in the nervous system. We discuss the possible role of sialin in normal development and in SASD pathogenesis, as a framework for further investigation of its function in these contexts. 相似文献
98.
Novakovic KE Villemagne VL Rowe CC Masters CL 《International psychogeriatrics / IPA》2005,17(Z1):S149-S194
Several genetic disorders, though rare, are associated or present with dementia. Developments in the field of genetics are contributing to clarify and expand our knowledge of the complex physiopathological mechanisms leading to neurodegeneration and cognitive decline. Disorders associated with misfolded and aggregated proteins and lipid, metal or energy metabolism are examples of the multifarious disease processes converging in the clinical features of dementia, either as its predominant feature, as in cases of Alzheimer's disease (AD) or frontotemporal dementia (FTD), or as part of a cohort of accompanying or late-developing symptoms, as in Parkinson's disease (PD) or amyotrophic lateral sclerosis with dementia (ALS-D). Awareness of these disorders, allied with recent advances in genetic, biochemical and neuroimaging techniques, may lead to early diagnosis, successful treatment and better prognosis. 相似文献
99.
Ruel M Masters RG Rubens FD Bédard PJ Pipe AL Goldstein WG Hendry PJ Mesana TG 《The Annals of thoracic surgery》2004,78(1):77-83
Background
Stroke is a devastating complication in patients with prosthetic valves, but characterization of its late occurrence from a large cohort is lacking.Methods
Three thousand one hundred eighty-nine adult patients who underwent a total of 3,576 operations for left-heart valve replacement were managed with contemporary anticoagulation guidelines and prospectively followed in a dedicated clinic. Total follow-up was 20,096 patient years. Bootstrapped survival analysis was used to determine the impact of patient and valve related factors on the incidence of stroke.Results
Most strokes were embolic. Linearized embolic stroke rates were 1.3% ± 0.2% per year for aortic bioprostheses, 1.4% ± 0.2% per year for aortic mechanical valves, 1.3% ± 0.3% per year for mitral bioprostheses, and 2.3% ± 0.4% per year for mitral mechanical valves (p = 0.002, vs other implant types). Age more than 75 years, female gender, and smoking were independent risk factors after aortic and mitral valve replacement. Atrial fibrillation, coronary disease, and tilting-disc mechanical prostheses were independent predictors of embolic stroke after aortic valve replacement. Preoperative left ventricular (LV) dysfunction was an independent risk factor in patients with mitral prostheses. Primary operative indication, diabetes, redo status, or the presence of two prosthetic valves were not associated with an increased hazard. The addition of acetyl salicylic or dipyridamole to warfarin anticoagulation did not significantly lower embolic stroke risk in patients with mechanical prostheses.Conclusions
Approximately 20% of patients with valve prostheses have an embolic stroke by 15 years after valve replacement. Some risk factors such as the avoidance of smoking, mitral mechanical prostheses, aortic tilting-disc valves, and proceeding to mitral surgery before LV dysfunction occurs are potentially modifiable. 相似文献100.
Masters KS Shah DN Walker G Leinwand LA Anseth KS 《Journal of biomedical materials research. Part A》2004,71(1):172-180
Valvular interstitial cells (VICs) possess many properties that make them attractive for use in the construction of a tissue-engineered valve; however, we have found that the surfaces to which VICs will adhere and spread are limited. For example, VICs adhere and spread on collagen and laminin-coated surfaces, but display altered morphology and do not proliferate. Interestingly, fibronectin (FN) was one adhesion protein that facilitated VIC adhesion and proliferation. Yet VICs did not spread on surfaces modified with RGD, a ubiquitous cell-adhesive peptide, nor with other FN-specific peptide sequences such as EILDV and PHSRN. Hyaluronic acid (HA) is a highly elastic polysaccharide that is involved in natural valve morphogenesis and possesses binding interactions with FN. Hyaluronic acid was modified to form photopolymerizable hydrogels, and VICs were found to spread and proliferate on HA-based gels, forming a confluent monolayer on the gels within 4 days. Modified HA retained its ability to specifically bind FN, allowing for the formation of gels containing both HA and FN. Valvular interstital cells cultured on HA surfaces displayed significantly increased production of extracellular matrix proteins, indicating that HA-based scaffolds may provide useful biological cues to stimulate heart valve tissue formation. 相似文献