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Digital Image Analysis (digital + image_analysis)

Distribution by Scientific Domains

Medical Sciences	64%
Life Sciences	14%
Chemistry	14%
2 Other Domains	8%

Selected Abstracts

Assessment of Proliferating Cell Nuclear Antigen Activity Using Digital Image Analysis in Breast Carcinoma Following Magnetic Resonance-Guided Interstitial Laser Photocoagulation

THE BREAST JOURNAL, Issue 5 2003
Soheila Korourian MD
Abstract: This study examines proliferative activity in tumor cells of patients with histologically documented invasive breast carcinoma treated with magnetic resonance-guided interstitial laser photocoagulation (MR-GILP). Immunohistochemical marker for proliferating cell nuclear antigen (PCNA), a nuclear protein abundant in actively proliferating cells, is used. The study demonstrates the effectiveness of MR-GILP in ablating tumor cells of infiltrating breast cancer. The diagnosis of infiltrating breast carcinoma was confirmed by core needle biopsies. Using a specially designed magnetic resonance imaging (MRI) device, rotating delivery of excitation off-resonance (RODEO), tumors were measured ranging from 1.8 to 4.0 cm in greatest dimension. Seven formalin-fixed, paraffin-embedded archival tissues from seven patients with infiltrating carcinoma, status post-MR-GILP, were analyzed. Using PCNA immunoperoxidase (Biomeda Corp.), the proliferative capability of the remaining tumor cells around the focus of laser photocoagulation was determined. The lesions were digitally acquired using a Nikon Eclipse E800 microscope with an automated stage. Images were analyzed using Cool SNAP image editing software (version 1.0). Appropriate thresholds were set for positive staining and limited concentric radial measurements of equal area between all samples were compared at radial millimeter intervals from the center of laser ablation. The integrated area occupied by PCNA-positive cells per radial millimeter from the charcoal site (the center of the laser) increased as the distance from this site increased (a mean average at each radial measurement revealed: at the 1 mm radius the positive integrated area was 0.0024 mm2; at 2 mm, 0.0145 mm2; at 3 mm, 0.0351 mm2; at 4 mm, 0.0696 mm2; at 5 mm, 0.1025 mm2; and at 6 mm, 0.1263 mm2). MR-GILP is an effective mean of ablating breast carcinoma. This treatment option may represent an alternative to lumpectomy for a single lesion ,1 cm, or make patients with two separate lesions eligible for lumpectomy. [source]

Investigation into the hydrodynamics of gas,solid fluidized beds using particle image velocimetry coupled with digital image analysis

THE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2008
Jan Albert Laverman
Abstract The hydrodynamics of a freely bubbling, pseudo 2-D fluidized bed has been investigated experimentally for different bed aspect ratios at different superficial gas velocities by using Particle Image Velocimetry (PIV) combined with Digital Image Analysis (DIA). Coupling of both non-invasive measuring techniques allows us to obtain information on both the bubble behaviour and emulsion phase circulation patterns simultaneously. In particular, the combination of DIA with PIV allows to correct for the influence of particle raining through the roof of the bubbles on the time-averaged emulsion phase velocity profiles. On a étudié de façon expérimentale l'hydrodynamique d'un lit fluidisé pseudo 2-D en bouillonnement libre, pour différents rapports de forme de lits à différentes vitesses de gaz superficielles par vélocimétrie à images de particules (PIV) combinée à l'analyse d'images numériques (DIA). Le couplage de deux techniques de mesure non invasives nous permet d'obtenir de l'information sur le comportement des bulles et les schémas de circulation de la phase d'émulsion, simultanément. En particulier, la combinaison de DIA et de PIV permet de corriger l'influence de la pluie de particules s'écoulant du toit de bulles sur les profils de vitesse de la phase d'émulsion moyennés dans le temps. [source]

Digital image analysis of the flagellar beat of activated and hyperactivated suncus spermatozoa

MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 4 2007
Takane Kaneko
Abstract The flagellar beat of hyperactivated Suncus spermatozoa was analyzed by digital imaging and was compared to that of the nonhyperactivated (activated) spermatozoa in order to examine the function of the accessory fibers during the flagellar beat and the sliding filament mechanism inducing the motility of the hyperactivated spermatozoa. Unusual large and long characteristics of the accessory fibers were involved in generating the gently curved bends and a low beat frequency. Examination of the motility parameters of the flagellar beat of the activated and hyperactivated spermatozoa attached to a slide glass by their heads revealed that there were two beating modes: a frequency-curvature dependent mode in the activated flagellar beat and a nearly constant frequency mode in the hyperactivated flagellar beat. The hyperactivated flagellar beat was characterized by sharp bends in the proximal midpiece and a low beat frequency. The sharp bends in the proximal midpiece were induced by the increase in the total length of the microtubule sliding at the flagellar base. The rate of microtubule sliding (sliding velocity) in the axoneme remained almost constant in the flagellar beat of both the activated and hyperactivated spermatozoa. Comparison of the sliding velocity in Suncus, golden hamster, monkey, and sea urchin sperm flagella with their stiffness suggests that the sliding velocity is determined by the stiffness at the flagellar base and that the same sliding microtubule system functions in both mammalian and echinoderm spermatozoa. Mol. Reprod. Dev. 74: 478,485, 2007. © 2006 Wiley-Liss, Inc. [source]

Digital image analysis of plus disease in retinopathy of prematurity

ACTA OPHTHALMOLOGICA, Issue 4 2009
Tariq Aslam
Abstract. An accurate assessment of retinopathy of prematurity (ROP) is essential in ensuring correct and timely treatment of this potentially blinding condition. Current modes of assessment are based upon clinical grading by expert examination of retinal changes. However, this may be subjective, unreliable and difficult and there has been significant interest in alternative means of measurement. These have been made possible through technological advancements in image capture and analysis as well as progress in clinical research, highlighting the specific importance of plus disease in ROP. Progress in these two fields has highlighted the potential for digital image analysis of plus disease to be used as an objective, reliable and valid measurement of ROP. The potential for clinical and scientific advancement through this method is argued and demonstrated in this article. Along with the potential benefits, there are significant challenges such as in image capture, segmentation, measurement of vessel width and tortuosity; these are also addressed. After discussing and explaining the challenges involved, the research articles addressing digital image analysis of ROP are critically reviewed. Benefits and limitations of the currently published techniques for digital ROP assessment are discussed with particular reference to the validity and reliability of outcome measures. Finally, the general limitations of current methods of analysis are discussed and more diverse potential areas of development are discussed. [source]

Bacterial diversity in maize rhizospheres: conclusions on the use of genetic profiles based on PCR-amplified partial small subunit rRNA genes in ecological studies

MOLECULAR ECOLOGY, Issue 1 2003
Achim Schmalenberger
Abstract A cultivation-independent approach based on polymerase chain reaction (PCR)-amplified partial small subunit rRNA genes and genetic profiling by single-strand conformation polymorphism (SSCP) was used to characterize the bacterial diversity inhabiting the rhizosphere of maize plants grown on an agricultural field. The community structures of two cultivars, a genetically engineered and a nonengineered variety, different herbicide regimes and soil tillage were compared with each other at two sampling dates. SSCP-profiles were generated with DNA from bacterial cell consortia with primers hybridizing to evolutionarily highly conserved rRNA gene regions. On silver-stained gels, each profile consisted of approx. 50 distinguishable bands. Similarity analyses of patterns recorded by digital image analyses could not detect any difference between cultivars or treatments that was greater than the variability between replicates. A total of 54 sequences recovered from different bands were identified and grouped into operational taxonomical units (OTUs). Surprisingly, only five of 40 OTUs contained sequences of both samplings. Three different bands from a profile were selected to test whether this small overlap was due to an incomplete recovery of sequences. From a faint band, two different OTUs were found when 12 clones were analysed, and from two strong bands 24 and 22 OTUs were detected from a total of 26 and 36 clones, respectively. The OTUs belonged to phylogenetically different groups of bacteria. Gene probes that were developed to target different bands of the profiles, however, indicated in Southern blot analyses that patterns between treatments, replicates and samplings, and even from two different growing seasons were highly conserved. Our study demonstrates that community profiles can consist of more sequences than detectable by staining and that gene probes in Southern blot can be a useful control to investigate the composition of microbial communities by genetic profiles. [source]

A comparative evaluation of digital imaging, retinal photography and optometrist examination in screening for diabetic retinopathy

DIABETIC MEDICINE, Issue 7 2003
J. A. Olson
Abstract Aims To compare the respective performances of digital retinal imaging, fundus photography and slit-lamp biomicroscopy performed by trained optometrists, in screening for diabetic retinopathy. To assess the potential contribution of automated digital image analysis to a screening programme. Methods A group of 586 patients recruited from a diabetic clinic underwent three or four mydriatic screening methods for retinal examination. The respective performances of digital imaging (n = 586; graded manually), colour slides (n = 586; graded manually), and slit-lamp examination by specially trained optometrists (n = 485), were evaluated against a reference standard of slit-lamp biomicroscopy by ophthalmologists with a special interest in medical retina. The performance of automated grading of the digital images by computer was also assessed. Results Slit-lamp examination by optometrists for referable diabetic retinopathy achieved a sensitivity of 73% (52,88) and a specificity of 90% (87,93). Using two-field imaging, manual grading of red-free digital images achieved a sensitivity of 93% (82,98) and a specificity of 87% (84,90), and for colour slides, a sensitivity of 96% (87,100) and a specificity of 89% (86,91). Almost identical results were achieved for both methods with single macular field imaging. Digital imaging had a lower technical failure rate (4.4% of patients) than colour slide photography (11.9%). Applying an automated grading protocol to the digital images detected any retinopathy, with a sensitivity of 83% (77,89) and a specificity of 71% (66,75) and diabetic macular oedema with a sensitivity of 76% (53,92) and a specificity of 85% (82,88). Conclusions Both manual grading methods produced similar results whether using a one- or two-field protocol. Technical failures rates, and hence need for recall, were lower with digital imaging. One-field grading of fundus photographs appeared to be as effective as two-field. The optometrists achieved the lowest sensitivities but reported no technical failures. Automated grading of retinal images can improve efficiency of resource utilization in diabetic retinopathy screening. Diabet. Med. 20, 528,534 (2003) [source]

Digital Analysis of Myocardial Contrast Echocardiography: A Clinical Study Using an Air-Filled Agent in Normal Subjects

ECHOCARDIOGRAPHY, Issue 3 2000
EDWARD A. GEISER M.D., F.A.C.C.
The purpose of the present study was to determine whether direct digital image analysis would allow improved detection of myocardial contrast. Eighteen normal subjects were recruited and separated into two groups. In group 1, the time-brightness curves of the left ventricular cavity and three myocardial perfusion beds were formed from digitized video tape, with output power and imaging time as secondary variables. In group 2, curves constructed from direct polar digital data were compared, with fundamental and second harmonic image formation as variables. In group 1 subjects, using fundamental imaging, the area under the curve in the left ventricular cavity increased slightly with intermittent imaging. No consistent myocardial opacification was identified. In group 2 subjects, using intermittent imaging, the area under the myocardial curve and peak intensity increased with high output second harmonic imaging in the left anterior descending and right coronary artery regions. Intermittent, second harmonic imaging and digital processing can demonstrate myocardial contrast even with an air-filled agent. [source]

The Characterization of Local Deformation and Fracture Properties , a Tool for Advanced Materials Design,

ADVANCED ENGINEERING MATERIALS, Issue 11 2006
O. Kolednik
Novel experimental techniques have been recently developed to measure local deformation and fracture properties. The techniques comprise quantitative fracture surface analysis and in-situ loading experiments in combination with digital image analysis. Examples are presented, demonstrating how these methods can be used to investigate the damage evolution in materials, to improve tools for the numerical simulation, and for the design of more fracture resistant materials and components. [source]

Measurement of stain on extracted teeth using spectrophotometry and digital image analysis

INTERNATIONAL JOURNAL OF DENTAL HYGIENE, Issue 3 2007
DL Lath
Abstract:, Aim:, The aim of this study was to assess the reliability and validate a customized image analysis system, designed for use within clinical trials of general dental hygiene and whitening products, for the measurement of stain levels on extracted teeth and to compare it with reflectance spectrophotometry. Method:, Twenty non-carious extracted teeth were soaked in an artificial saliva, brushed for 1 min using an electric toothbrush and a standard toothpaste, bleached using a 5.3% hydrogen peroxide solution and cycled for 6 h daily through a tea solution. CIE L* values were obtained after each treatment step using the customized image analysis system and a reflectance spectrophotometer. A statistical analysis was carried out in SPSS. Results:, Fleiss' coefficient of reliability for intra-operator repeatability of the image analysis system and spectrophotometry was 0.996 and 0.946 respectively. CIE L* values were consistently higher using the image analysis compared with spectrophotometry, and t -tests for each treatment step showed significant differences (P < 0.05) for the two methods. Limits of agreement between the methods were ,27.95 to +2.07, with a 95% confidence of the difference calculated as ,14.26 to ,11.84. The combined results for all treatment steps showed a significant difference between the methods for the CIE L* values (P < 0.05). Conclusion:, The image analysis system has proven to be a reliable method for assessment of changes in stain level on extracted teeth. The method has been validated against reflectance spectrophotometry. This method may be used for pilot in vitro studies/trials of oral hygiene and whitening products, before expensive in vivo tests are carried out. [source]

Retinal vascular image analysis as a potential screening tool for cerebrovascular disease: a rationale based on homology between cerebral and retinal microvasculatures

JOURNAL OF ANATOMY, Issue 4 2005
Niall Patton
Abstract The retinal and cerebral microvasculatures share many morphological and physiological properties. Assessment of the cerebral microvasculature requires highly specialized and expensive techniques. The potential for using non-invasive clinical assessment of the retinal microvasculature as a marker of the state of the cerebrovasculature offers clear advantages, owing to the ease with which the retinal vasculature can be directly visualized in vivo and photographed due to its essential two-dimensional nature. The use of retinal digital image analysis is becoming increasingly common, and offers new techniques to analyse different aspects of retinal vascular topography, including retinal vascular widths, geometrical attributes at vessel bifurcations and vessel tracking. Being predominantly automated and objective, these techniques offer an exciting opportunity to study the potential to identify retinal microvascular abnormalities as markers of cerebrovascular pathology. In this review, we describe the anatomical and physiological homology between the retinal and cerebral microvasculatures. We review the evidence that retinal microvascular changes occur in cerebrovascular disease and review current retinal image analysis tools that may allow us to use different aspects of the retinal microvasculature as potential markers for the state of the cerebral microvasculature. [source]

Tissue alterations after tooth extraction with and without surgical trauma: a volumetric study in the beagle dog

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2008
Stefan Fickl
Abstract Objectives: The aim of this study is to evaluate whether tooth extraction without the elevation of a muco-periosteal flap has advantageous effects on the resorption rate after tooth extraction. Material and Methods: In five beagle dogs polyether impressions were taken before the surgery. The roots of the first and second pre-molars (P1 and P2) were extracted and the sites were assigned to one of the following treatments: treatment group (Tx) 1, no treatment; Tx 2, surgical trauma (flap elevation and repositioning); Tx 3, the extraction socket was filled with BioOss Collagen® and closed with a free soft-tissue graft; Tx 4, after flap elevation and repositioning, the extraction socket was treated with BioOss Collagen® and a free soft-tissue graft. Impressions were taken 2 and 4 months after surgery. The casts were scanned, matched together with baseline casts and evaluated with digital image analysis. Results: The "flapless groups" demonstrated significant lower resorption rates both when using socket-preservation techniques and without. Furthermore, socket-preservation techniques yielded better results compared with not treating the socket. Conclusion: The results demonstrate that leaving the periosteum in place decreases the resorption rate of the extraction socket. Furthermore, the treatment of the extraction socket with BioOss Collagen® and a free gingival graft seems beneficial in limiting the resorption process after tooth extraction. [source]

The biometry of gills of 0-group European flounder

JOURNAL OF FISH BIOLOGY, Issue 4 2000
M. G. J. Hartl
The gill surface area of 0-group, post-metamorphic Pleuronectes flesus L. was examined using digital image analysis software and expressed in relation to body mass according to the equation log Y=loga+c logW (a=239·02; c=0·723). The components that constitute gill area, total filament length, interlamellar space and unilateral lamellar area were measured. The measurement of the length of every filament on all eight arches showed that commonly used methods of calculation can lead to an under-estimation of up to 24% of total filament length. Direct measurements of unilateral lamellar area with digital image analysis showed that previously reported gill area data for the same species was over-estimated by as much as 58%. In addition, in this species the neglect of gill pouch asymmetry after metamorphosis, can bring about a 14% over-estimation of total gill area. [source]

Tumor interstitial fluid pressure may regulate angiogenic factors in osteosarcoma

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 11 2008
Saminathan S. Nathan
Abstract We have previously shown that osteosarcomas (OS) have states of increased interstitial fluid pressure (IFP), which correlate with increased proliferation and chemosensitivity. In this study, we hypothesized that constitutively raised IFP in OS regulates angiogenesis. Sixteen patients with the clinical diagnosis of OS underwent blood flow and IFP readings by the wick-in-needle method at the time and location of open biopsy. Vascularity was determined by capillary density in the biopsy specimens. We performed digital image analysis of immunohistochemical staining for CD31, VEGF-A, VEGF-C, and TPA on paraffin-embedded tissue blocks of the biopsy samples. Clinical results were validated in a pressurized cell culture system. Interstitial fluid pressures in the tumors (mean 33.5,±,SD 17.2 mmHg) were significantly higher (p,=,0.00001) than that in normal tissue (2.9,±,5.7 mmHg). Pressure readings were significantly higher in low vascularity tumors compared to high vascularity tumors (p,<,0.001). In the OS cell lines, growth in a pressurized environment was associated with VEGF-A downregulation, VEGF-C upregulation, and TPA upregulation. The reverse was seen in the OB cell line. Growth in the HUVEC cell line was not significantly inhibited in a pressurized environment. Immunohistochemical assessment for VEGF-A (p,=,0.01), VEGF-C (p,=,0.008), and TPA (p,=,0.0001) translation were consistent with the findings on PCR. Our data suggests that some molecules in angiogenesis are regulated by changes in IFP. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1520,1525, 2008 [source]

Interfragmentary surface area as an index of comminution severity in cortical bone impact

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2005
Christina L. Beardsley
Abstract A monotonic relationship is expected between energy absorption and fracture surface area generation for brittle solids, based on fracture mechanics principles. It was hypothesized that this relationship is demonstrable in bone, to the point that on a continuous scale, comminuted fractures created with specific levels of energy delivery could be discriminated from one another. Using bovine cortical bone segments in conjunction with digital image analysis of CT fracture data, the surface area freed by controlled impact fracture events was measured. The results demonstrated a statistically significant (p < 0.0001) difference in measured de novo surface area between three specimen groups, over a range of input energies from 0.423 to 0.702 J/g. Local material properties were also incorporated into these measurements via CT Hounsfield intensities. This study confirms that comminution severity of bone fractures can indeed be measured on a continuous scale, based on energy absorption. This lays a foundation for similar assessments in human injuries. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]

The effects of irrigation, nitrogen fertilizer and grain size on Hagberg falling number, specific weight and blackpoint of winter wheat

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2004
Matthew P Clarke
Abstract The effects of irrigation and nitrogen (N) fertilizer on Hagberg falling number (HFN), specific weight (SW) and blackpoint (BP) of winter wheat (Triticum aestivum L) were investigated. Mains water (+50 and +100 mm month,1, containing 44 mg NO3, litre,1 and 28 mg SO42, litre,1) was applied with trickle irrigation during winter (17 January,17 March), spring (21 March,20 May) or summer (24 May,23 July). In 1999/2000 these treatments were factorially combined with three N levels (0, 200, 400 kg N ha,1), applied to cv Hereward. In 2000/01 the 400 kg N ha,1 treatment was replaced with cv Malacca given 200 kg N ha,1. Irrigation increased grain yield, mostly by increasing grain numbers when applied in winter and spring, and by increasing mean grain weight when applied in summer. Nitrogen increased grain numbers and SW, and reduced BP in both years. Nitrogen increased HFN in 1999/2000 and reduced HFN in 2000/01. Effects of irrigation on HFN, SW and BP were smaller and inconsistent over year and nitrogen level. Irrigation interacted with N on mean grain weight: negatively for winter and spring irrigation, and positively for summer irrigation. Ten variables derived from digital image analysis of harvested grain were included with mean grain weight in a principal components analysis. The first principal component (,size') was negatively related to HFN (in two years) and BP (one year), and positively related to SW (two years). Treatment effects on dimensions of harvested grain could not explain all of the effects on HFN, BP and SW but the results were consistent with the hypothesis that water and nutrient availability, even when they were affected early in the season, could influence final grain quality if they influenced grain numbers and size. Copyright © 2004 Society of Chemical Industry [source]

Transplantation for hilar cholangiocarcinoma

LIVER TRANSPLANTATION, Issue S10 2004
Julie K. Heimbach
Key Points 1Patients with primary sclerosing cholangitis (PSC) have a 8 to 12% risk of developing cholangiocarcinoma (CCA). 2Cytologic techniques for aneuploidy such as digital image analysis and fluorescence in situ hybridization increase the detection rate for CCA. 3Survival following resection for CCA is 20% to 40% at 5 years. 4Survival following liver transplantation for unresectable, perihilar CCAs, mass lesion if present <3 cm, is greater than 80% at 5 years. 5Patients with intrahepatic CCAs are not eligible for liver transplantation. (Liver Transpl 2004;10:S65,S68.) [source]

Fluorescein leakage of the optic disc: time course in primary open-angle glaucoma

OPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2010
Niklas Plange
Abstract Purpose:, To identify and quantify the time course of fluorescein leakage of the optic nerve head in primary open-angle glaucoma (POAG) and controls. Methods:, Twenty patients with POAG (aged 58 ± 10 years) and 14 controls (aged 51 ± 12 years, p = 0.07) were included in a prospective study. Fluorescein leakage of the optic disc was quantified using digital image analysis. A new leakage ratio (fluorescence of the optic disc divided by fluorescence of the surrounding retina) was defined and fluorescein leakage was quantified at 7,8, 9,10, 11,12, and 13,14 min after injection of 2.5 cc sodium fluorescein (10%). Results:, The fluorescein leakage exhibited a significantly different time course with higher leakage ratio values in POAG compared to controls (7,8 min: 1.24 ± 0.32 vs 1.16 ± 0.12; 9,10 min: 1.37 ± 0.37 vs 1.19 ± 0.1; 11,12 min: 1.38 ± 0.36 vs 1.24 ± 0.13; 13,14 min: 1.44 ± 0.36 vs 1.27 ± 0.13; p = 0.004). The change in optic disc fluorescence from 7,8 min to 9,10 min was significantly higher in POAG compared to controls (0.13 ± 0.09 vs 0.03 ± 0.07; p = 0.002). Conclusion:, The time course of fluorescein leakage is significantly different in POAG compared to controls. This might reflect damage of the optic disc vasculature related to increased vascular permeability. [source]

Continuous recording of accommodation and pupil size using the Shin-Nippon SRW-5000 autorefractor

OPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 2 2001
J. S. Wolffsohn
Summary A newly released commercial autorefractor, the Shin-Nippon SRW-5000 (Japan), has been found to be valid compared to subjective refraction and repeatable over a wide prescription range. Its binocular open field-of-view allows the accommodative state to be monitored while a natural environment is viewed. In conventional static mode, the device can take up to 45 readings in 1 min using digital image analysis of the reflected retinal image of a measurement ring. Continuous on-line analysis of the ring provides high (up to 60 Hz) temporal resolution of the refractive state to an accuracy of <0.001 D. Pupil size can also be analysed to a resolution of <0.001 mm. The measurement of accommodation and pupil size was relatively unaffected by eccentricity of viewing up to ±10° and instrument focusing inaccuracies of ±5 mm. The resolution properties of the analysis are shown to be ideal for measurement of dynamic accommodation and pupil responses. [source]

Investigation into the hydrodynamics of gas,solid fluidized beds using particle image velocimetry coupled with digital image analysis

The Mechanism of Hearing Loss in Paget's Disease of Bone,

THE LARYNGOSCOPE, Issue 4 2004
Edwin M. Monsell MD
Abstract Objectives/Hypothesis The mechanism of hearing loss (HL) in Paget's disease of bone was investigated. The present study was a systematic, prospective, controlled set of clinical investigations to test the hypothesis that there is a general underlying mechanism of HL in Paget's disease of bone and to gain additional insights into the auditory and otologic dynamics of this disease. Specific questions were 1) whether the mechanism is cochlear or retrocochlear and 2) whether the bone mineral density of the cochlear capsule is related to hearing levels. Study Design Several double-blinded, cross-sectional, prospective, correlational studies were conducted in a population of elderly human subjects with skull involvement with Paget's disease versus a control population of elderly subjects free of Paget's disease. Demographic and clinical data were recorded. Longitudinal observations were made in subjects under treatment. Methods Subjects were recruited from a Paget's disease clinic. Pure-tone auditory thresholds, word recognition, and auditory brainstem responses (ABRs) were recorded. The dimensions of the internal auditory canals were measured using computed tomographic (CT) images and digital image analysis. The precision, accuracy, and temporal stability of methods to measure the bone mineral density of the cochlear capsule and an adjacent area of nonotic capsule bone were validated and applied. Correlations were sought between hearing levels and cochlear capsule bone mineral density. Results ABRs were recorded in 64 ears with radiographically confirmed Paget's disease involving the skull. Responses were absent in eight ears, all of which had elevated high pure-tone thresholds. ABRs were interpreted as normal in 56 ears; none were abnormal. The mid-length diameter and minimum diameter of the internal auditory canal of 68 temporal bones from subjects with Paget's disease were found to have no statistically significant relationship to hearing thresholds. The Pearson product-moment correlation coefficients (age- and sex-adjusted) in the group with Paget's disease involving the temporal bone were ,0.63 for left ears and ,0.73 for right ears for high-frequency air conduction pure-tone thresholds (mean of 1, 2, and 4 kHz) versus cochlear capsule density. Correlation coefficients (age- and sex-adjusted) between cochlear capsule density and air-bone gap (mean at 0.5 and 1 kHz) for the affected group were ,0.67 for left ears and ,0.63 for right ears. All correlations between hearing thresholds and cochlear capsule density in pagetic subjects were significant at P < .001. The regressions were consistent throughout the ranges of hearing level. There were no significant correlations between cochlear capsule mean density and hearing level in the volunteer subjects. Conclusions The evidence supports the existence of a general, underlying, cochlear mechanism of pagetic HL that is closely related to loss of bone mineral density in the cochlear capsule. This mechanism accounts well for both the high-frequency sensorineural HL and the air-bone gap. Early identification, radiographic diagnosis of temporal bone involvement, and vigorous treatment with third-generation bisphosponates are important to limit the development and progression of pagetic HL. [source]

First Evidence of Genetic Imbalances in Angiofibromas

THE LARYNGOSCOPE, Issue 2 2002
Bernhard Schick MD
Abstract Objective/Hypothesis Angiofibromas are clinically well characterized by their origin at the posterior lateral nasal wall close to the sphenopalatine foramen, their occurrence in male adolescent patients, and the histological findings of a benign fibrovascular neoplasm with irregular, endothelium-lined vascular spaces in a fibrous stroma. However, their etiology and genetic causes remain unknown. The present study addresses genetic imbalances in angiofibromas. Study Design The present pilot study compared genomic hybridization in three angiofibromas to search for chromosomal abnormalities in this rare tumor. Methods Fluorescence-marked normal DNA and angiofibroma DNA were compared using genomic hybridization screening to detect chromosomal abnormalities. Their binding ratio to metaphase chromosomes were analyzed by special digital image analysis. Results Chromosomal gains and losses showing a high level of agreement were detected in all three angiofibromas. Specifically, DNA gains were observed on chromosomes 3q, 4q, 5q, 6q, 7q, 8q, 12p, 12q, 13q, 14q, 18q, 21q, and X, and DNA losses were screened on chromosomes 17, 19p, 22q, and Y. Finding chromosomal abnormalities at the sex chromosomes X and Y of this rare tumor is remarkable. Concurrent chromosomal gain on 8q12q22 was noted in all three tumor specimens. Conclusions Comparative genomic hybridization is suitable for screening angiofibromas on a genetic level. The results on these screens indicate that further genetic investigations of this rare benign tumor may provide more details about the tumor's genetic abnormalities and perhaps clarify the etiology of angiofibromas. [source]

Cardiovascular disease in patients with inflammatory rheumatic disease is associated with up-regulation of markers of inflammation in cardiac microvessels and cardiomyocytes

ARTHRITIS & RHEUMATISM, Issue 3 2010
Cecilia Grundtman
Objective Various inflammatory rheumatic diseases (IRDs) are associated with increased mortality due to cardiovascular disease. The aim of this study was to investigate heart biopsy specimens obtained from patients undergoing coronary artery bypass grafting and compare markers of inflammation and endothelial cell activation in the cardiac and skeletal muscle of patients with and those without IRD. Methods Paired biopsy specimens of cardiac and skeletal muscle were obtained from 22 consecutive patients with IRD and 8 patients without IRD, all of whom were undergoing coronary artery bypass grafting. The biopsy specimens were evaluated in a blinded manner by conventional microscopy and digital image analysis for cell markers (CD3, CD4, CD8, CD68, CD163, and CD31), HLA (HLA,ABC, HLA,DR, and HLA,DQ), adhesion molecules (intercellular adhesion molecule 1 and vascular cell adhesion molecule 1), and proinflammatory cytokines (interleukin-1,, interleukin-1,, and tumor necrosis factor). Results Patients with IRD had significantly higher expression of adhesion molecules, proinflammatory cytokines, and all classes of HLA on cardiomyocytes and endothelial cells but no increase on mononuclear cells in the myocardium compared with patients without IRD. Furthermore, cardiac muscle from patients with IRD displayed significantly higher local expression of inflammation and activation of cardiac microvessels compared with skeletal muscle from the same patients. Conclusion Patients with cardiovascular disease had increased expression of adhesion molecules, HLA, and proinflammatory cytokines in heart tissue, indicating local inflammation involving microvessels and cardiomyocytes that could play a role in the pathogenesis of cardiovascular disease. The more pronounced changes in patients with IRD compared with patients without IRD might contribute to the increased risk of cardiovascular disease and premature death in patients with IRD. [source]

Involvement of breast cancer resistance protein expression on rheumatoid arthritis synovial tissue macrophages in resistance to methotrexate and leflunomide

ARTHRITIS & RHEUMATISM, Issue 3 2009
Joost W. van der Heijden
Objective To determine whether multidrug-resistance efflux transporters are expressed on immune effector cells in synovial tissue from patients with rheumatoid arthritis (RA) and compromise the efficacy of methotrexate (MTX) and leflunomide (LEF). Methods Synovial tissue biopsy samples obtained from RA patients before treatment and 4 months after starting treatment with MTX (n = 17) or LEF (n = 13) were examined by immunohistochemical staining and digital image analysis for the expression of the drug efflux transporters P-glycoprotein, multidrug resistance,associated protein 1 (MRP-1) through MRP-5, MRP-8, MRP-9, and breast cancer resistance protein (BCRP), and the relationship to clinical efficacy of MTX and LEF was assessed. Results BCRP expression was observed in all RA synovial biopsy samples, both pretreatment and posttreatment, but not in control noninflammatory synovial tissue samples from orthopedic patients. BCRP expression was found both in the intimal lining layer and on macrophages and endothelial cells in the synovial sublining. Total numbers of macrophages in RA patients decreased upon treatment; in biopsy samples with persistently high macrophage counts, 2-fold higher BCRP expression was observed. Furthermore, median BCRP expression was significantly increased (3-fold) in nonresponders to disease-modifying antirheumatic drugs (DMARDs) compared with responders to DMARDs (P = 0.048). Low expression of MRP-1 was found on synovial macrophages, along with moderate expression in T cell areas of synovial biopsy specimens from one-third of the RA patients. Conclusion These findings show that the drug resistance,related proteins BCRP and MRP-1 are expressed on inflammatory cells in RA synovial tissue. Since MTX is a substrate for both BCRP and MRP-1, and LEF is a high-affinity substrate for BCRP, these transporters may contribute to reduced therapeutic efficacy of these DMARDs. [source]

Long-term effects of chondroitins 4 and 6 sulfate on knee osteoarthritis: The study on osteoarthritis progression prevention, a two-year, randomized, double-blind, placebo-controlled trial

ARTHRITIS & RHEUMATISM, Issue 2 2009
André Kahan
Objective To assess the long-term effects of chondroitins 4 and 6 sulfate (CS) on the radiographic progression of, and symptom changes associated with, knee osteoarthritis (OA). Methods We performed an international, randomized, double-blind, placebo-controlled trial in which 622 patients with knee OA were randomly assigned to receive either 800 mg CS (n = 309 patients) or placebo (n = 313 patients) once daily for 2 years. Radiographs of the target knee, using the Lyon schuss view, were obtained at the time of enrollment and at 12, 18, and 24 months. The minimum joint space width (JSW) of the medial compartment of the tibiofemoral joint was assessed by digital image analysis. The primary outcome was the loss in minimum JSW over 2 years. Results The intent-to-treat analysis demonstrated a significant reduction (P < 0.0001) in minimum JSW loss in the CS group (mean ± SEM ,0.07 ± 0.03 mm) as compared with the placebo group (,0.31 ± 0.04 mm). The percentage of patients with radiographic progression ,0.25 mm was significantly reduced in the CS group compared with the placebo group (28% versus 41% [P < 0.0005]; relative risk reduction 33% [95% confidence interval 16,46%]). The number of patients needed to treat was 8 (95% confidence interval 5,17). Pain improved significantly faster in the CS group than in the placebo group (P < 0.01). There were no differences in safety between groups. Conclusion The long-term combined structure-modifying and symptom-modifying effects of CS suggest that it could be a disease-modifying agent in patients with knee OA. [source]

Comparison of synovial tissues from the knee joints and the small joints of rheumatoid arthritis patients: Implications for pathogenesis and evaluation of treatment

ARTHRITIS & RHEUMATISM, Issue 8 2002
Maarten C. Kraan
Objective Serial synovial biopsy samples are increasingly being used for the evaluation of novel therapies for rheumatoid arthritis (RA). Most studies have used tissues from knee biopsies, but technical improvements have made serial small joint arthroscopy feasible as well. Theoretically, there could be differences in the features of synovial inflammation between various joints as a result of mechanical factors, differences in innervation, and other factors. We therefore undertook this study to compare the cell infiltrate in paired synovial biopsy samples from inflamed knee joints and paired inflamed small joints of patients with RA. Methods Nine RA patients with both an inflamed knee joint and an inflamed small joint (wrist or metacarpophalangeal joint) underwent an arthroscopic synovial biopsy of both joints on the same day. Multiple biopsy specimens were collected and stained for macrophages, T cells, plasma cells, fibroblast-like synoviocytes, and interleukin-6 (IL-6) by immunohistochemistry. Sections were evaluated by digital image analysis. Results There were no significant differences in mean cell numbers for all markers investigated in samples from the knee joint compared with samples from the small joints. We detected statistically significant correlations for the numbers of sublining macrophages, T cells, and plasma cells, as well as for IL-6 expression, between the knee joint and the small joints. However, there was no significant correlation between different joints for the numbers of intimal macrophages or fibroblast-like synoviocytes. Conclusion The results of this study show that the inflammation in one inflamed joint is generally representative of that in other inflamed joints. Therefore, it is possible to use serial samples from the same joint, selecting either large or small joints, for the evaluation of antirheumatic therapies. [source]

Combined Wear Behavior and Long-Term Implant-Bone Fixation of Total Knee Replacement: A Novel In Vitro Set-up

ARTIFICIAL ORGANS, Issue 5 2010
Michele Spinelli
Abstract The success of a total knee replacement (TKR) strongly depends on the prosthetic design; this includes on one hand the best choice of the bearing materials to minimize wear, on the other hand a good orientation of the prosthetic components with respect to the loading directions. The aim of this study was to investigate the feasibility of a new experimental setup combining two fundamental aspects for the long-term success of knee implants: wear and micromotions. A novel procedure was used to simulate working conditions as close as possible to in vivo ones and to measure implant-bone micromotion, by means of fixing the femoral component of the prosthesis to the distal part of a synthetic femur to be tested through a knee simulator. Gravimetric wear of the tibial specimens was assessed at regular intervals. Implant-bone inducible micromotions and permanent migrations were measured at three locations throughout the test. Wear patterns on tibial specimens were characterized through a standardized protocol based on digital image analysis; fatigue damage in the cement was quantified. Some initial conditioning was noticed both in the wear process and microcracking distribution within the cement mantle. Similarity in wear tracks observed on tibial inserts and other retrieval studies, coupled with clinically consistent migration patterns for TKR, supports the efficacy of the new in vitro method presented. [source]

Yield prediction from digital image analysis: A technique with potential for vineyard assessments prior to harvest

AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2004
GREGORY M. DUNN
Abstract Digital photographs were taken of four 1 m × 1 m portions of canopy of Cabernet Sauvignon grapevines, as they were being progressively de-fruited close to harvest. The program EasyAccess version 6.3 was used to select ,fruit' pixels by visually setting red, green and blue threshold values and tolerances for the first image and applying these to all other images. The program was then used to automatically count ,fruit' pixels and the total number of pixels for each image. Even though two hours separated the first and last photographs, the ratio of ,fruit' pixels to total image pixels explained 85% of the variation in yield (kg per linear m of fruiting wire) for all 16 vine × de-fruiting combinations. This improved to between 94 and 99% for individual portions of canopy. Implications from our present digital image analysis for future development of both automated and spatially aware methods to predict vineyard yield are discussed. [source]

Association between intraplaque haemorrhage in the carotid atherosclerotic lesion, the degree of internal carotid artery stenosis and timing of ischaemic neurological events

BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 4 2001
R. Mofidi
Background: Expansion of carotid atherosclerotic plaques as a result of intraplaque haemorrhage has been implicated in the development of ischaemic neurological events. The relationship between the quantity of haemorrhage in the dominant atherosclerotic lesion, the degree of internal carotid artery (ICA) stenosis and the chronology of patients' symptoms was examined. Methods: Consecutive patients undergoing carotid endarterectomy were included. The nature and timing of symptoms were recorded. Aortic arch injection digital subtraction angiography was performed before operation. Carotid endarterectomy specimens were serially sectioned and examined histologically. The amount of intraplaque haemorrhage was measured with digital image analysis. The influence of timing of symptoms on the quantity of intraplaque haemorrhage was compared with Kaplan,Meier analysis. Correlation between degree of ICA stenosis and quantity of intraplaque haemorrhage was assessed by means of regression analysis. Results: Seventy-four patients (20 asymptomatic, 54 symptomatic) were included. The median latency of symptoms was 28 (1,600) days. Intraplaque haemorrhage was common: 54 (73 per cent) of 74 patients. Mean(s.e.m.) cumulative symptom-free survival before operation for patients with no intraplaque haemorrhage was 0·71(0·11), compared with 0·58(0·11) in those exhibiting haemorrhage in less than 50 per cent of the plaque area, and 0·20(0·07) in lesions with over 50 per cent (P = 0·002). A close correlation was observed between the degree of ICA stenosis and haemorrhagic content of the dominant atherosclerotic lesion (r2 = 0·433, P < 0·001). Conclusion: These results confirm the association between intraplaque haemorrhage and the degree of ICA stenosis. They further demonstrate an association between the size of haemorrhage and timing of neurological events, suggesting a causative role for intraplaque haemorrhage in the development of ischaemic neurological events. © 2001 British Journal of Surgery Society Ltd [source]

Visual fields and optic disc morphology in very low birthweight adolescents examined with magnetic resonance imaging of the brain

ACTA OPHTHALMOLOGICA, Issue 8 2009
Kerstin Hellgren
Abstract. Purpose:, We aimed to evaluate visual fields (VFs) and optic disc morphology in very low birthweight (VLBW) adolescents compared with age- and gender-matched controls, and to relate the findings to magnetic resonance imaging (MRI) results. Methods:, Fifty-nine VLBW adolescents and 55 age- and gender-matched controls with normal birthweight were examined. Visual fields were tested using computerized rarebit perimetry (RB). Optic nerve and retinal vessel morphology were evaluated by digital image analysis of fundus photographs. Brain MRI was conducted in the VLBW subjects. Results:, Ten of the 57 VLBW subjects (p = 0.022) had subnormal VF results defined as a mean hit rate below the fifth percentile of the controls (i.e. < 89%). All of these also had significantly lower mean hit rates (p = 0.039) in the inferior hemifield. Sixteen of 57 (28%) VLBW subjects had white matter damage of immaturity (WMDI) on MRI. Six of 15 subjects with WMDI (who underwent VF testing) also had subnormal RB results, compared with four of 39 with normal MRI findings (p = 0.02). The mean neural retinal rim area was 9% smaller (p = 0.018) in the VLBW group than in the control group. The VLBW adolescents had a significantly higher index for tortuosity of arterioles than the controls (p < 0.001). Conclusions:, In the present study, 18% of all VLBW adolescents and 40% of those with WMDI had subnormal RB VF findings. The VLBW group had increased arterial tortuosity and a somewhat smaller (9%) mean neural retinal rim area than the control group. Thus sequels to VLBW appear to persist in adolescence. [source]