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http://www.webmedcentral.com/images/Header_Logo.giftext/html2011-03-21T20:42:53+01:00http://www.webmedcentral.com/Dr. Tak S ChingThe Accuracy of Commercial Blood Uric Acid Meters on Blood Uric Acid Level Measurement
http://www.webmedcentral.com/article_view/1778
High blood uric acid level is a risk factor for gout. To reduce the gout complications, patients need to measure their blood uric acid levels and take medication if necessary. Several commercial blood uric acid meters are available in the market. The aim of this study is to investigate the accuracy of two commercial blood uric acid meters, MultiSure and BeneCheck Pluse Meter, on blood uric acid level measurement. Eleven subjects participated in this study and their blood uric acid level is measured by the routine method in hospital and by the two commercial meters. Results showed that the two commercial meters always overestimates the situation of the user. Moreover, a fair correlation (r2 < 0.5) between the blood uric acid level obtained by the routine method and by the two commercial meters was observed. In conclusion, the accuracy of the two commercial meters to reflect a user’s blood uric acid level is still questionable.text/html2012-01-01T10:52:08+01:00http://www.webmedcentral.com/Dr. Charles J OsierCompression Failure Analysis of Porous Pmma - A Pilot Study
http://www.webmedcentral.com/article_view/1092
We hypothesized that porous PMMA could maintain structural strength at porosities high enough to increase elution characteristics. Porous PMMA cylinders were formed and tested to failure in compression. Compositions of 11.1%, 20%, 27.3% and 33.7% sucrose by mass were tested and failure load compared to non-porous PMMA. Testing demonstrated a 2.19 MPa linear decrease (p < 0.0005) in compression strength per gram of sucrose added. Analysis of strength as a function of time revealed an initial 7.9% decrease (p = 0.001) in compression strength followed by trend reversal and an ultimate 10.8% increase (p < 0.001) from minimum values over six weeks. Our failure analysis supports the hypothesis that adequate compression strength can be maintained while significantly increasing the porosity of PMMA to levels shown to improve elution characteristics. text/html2012-03-27T14:14:18+01:00http://www.webmedcentral.com/Dr. Arndt P SchulzChemical Characterization and Degradation behavior of a Polylactide Surgical Implant for the Fixation of osteochondral Fragments after activation with Ultrasound energy
http://www.webmedcentral.com/article_view/3199
The purpose of this study was to demonstrate that the ultrasonic energy used to melt the tip of an absorbable polylactide Pin (SonicPin) does not have a significant effect on the chemical characterization and associated degradation properties of the material. The results indicate that the polylactide Pin after ultrasound is chemically equivalent to the SonicPin prior to ultrasound with regard to chemical structure and risk of leachable compounds. The evidence gathered from literature and testing suggests that any potential toxicological risk to the patient is not amplified by the application of ultrasonic energy to melt the tip of the device.Keywords: SonicPin, Biocompatibility, Polylactide, Osteochondral fragment, Ultrasoundtext/html2012-07-17T16:55:01+01:00http://www.webmedcentral.com/Prof. Maurizio BaroniMultiscale Filtering and Neural Network Classification for Segmentation and Analysis of Retinal Vessels.
http://www.webmedcentral.com/article_view/3588
The blood vessel segmentation method described in this paper aims at minimizing the false positive rate, while maintaining high accuracy. Though developed for color retinal images, it can be applied to other tree-like vascular images as well. A computer vision approach is devised that mimics the image reading by expert people, based on a two stage process, perception and interpretation. The first stage adopts multiscale filtering to detect objects of different sizes: a two scale Laplacian of Gaussian scheme is used with the related sigma values chosen according to the smallest and greatest vessel widths. An approximate segmentation is achieved simply by means of the Laplacian sign. The interpretation stage is application-specific and accomplishes classification and quantitative analysis. The skeleton of the binary structures is subdivided in vessel segments, their features (position, orientation, length and width) are fed into an artificial neural network, after back-propagation training. The segments classified as vessels are assembled into the vascular tree by rule-based tracking. Results are evaluated on STARE and DRIVE data bases. Accuracy is 95% and the false positive rate is decreased to about 1%. The application on fundus images of infants with retinopathy of prematurity is also described.text/html2013-02-25T07:30:57+01:00http://www.webmedcentral.com/Dr. Pratap V KompalliStem Cells -A Review
http://www.webmedcentral.com/article_view/4046
Stem cell research has the potential to affect the lives of millions of people around the world. This research is now recently front page news because of the controversy surrounding the derivation of stem cells from human embryos. Realizing the promise of stem cells for yielding new medical therapies will require to grapple with more than just scientific uncertainties. The stem cell debate has lead scientists and non scientists alike to contemplate profound issues, such as who we are and what makes us human beings. The excitement and the controversy surrounding stem cells leads to lots of workshops conduction all over the world with representatives from various fields like molecular biology, immunology, cardiology, hematology, Neuro sciences, developmental biology, cancer, dentistry etc, all addressed the following scientific questions like what are stem cells. What are their sources? What biological differences exist between cells of different origin? What is the potential of stem cells for regenerative medicine and what obstacles must be overcome to make them useful for medical practices etc. On the other hand questions related to ethical issues, philosophy, law and other issues relevant to public policy consideration were considered. Hence an attempt has been made in this review to give a brief idea of the past, present and future of regenerative medicine.text/html2013-08-21T14:35:38+01:00http://www.webmedcentral.com/Ms. Raquel O RodriguesRed Blood Cells deformability index assessment in a hyperbolic microchannel: the diamide and glutaraldehyde effect
http://www.webmedcentral.com/article_view/4375
Red blood cells (RBCs) deformability can be defined as the ability of the cells to deform when subjected to certain flow conditions. In this work, a microfluidic system composed of a microchannel with a hyperbolic-shaped contraction was used to investigate the effect of both diamide and glutaraldehyde on the cell deformation index (DI) of human and ovine RBCs. An adequate image analysis technique was used to measure the DIs of the RBCs travelling in the regions of interest. The results show that the RBCs exposed to diamide and glutaraldehyde decrease their DIs and become more rigid. text/html2013-08-21T14:35:17+01:00http://www.webmedcentral.com/Mr. Elmano PintoCell-Free Layer (CFL) Analysis in a Polydimethysiloxane (PDMS) Microchannel: a Global Approach
http://www.webmedcentral.com/article_view/4374
The cell-free layer (CFL) is a hemodynamic phenomenon that has an important contribution to the rheological properties of blood flowing in microvessels. The present work aims to find the closest function describing RBCs flowing around the cell depleted layer in a polydimethysiloxane (PDMS) microchannel with a diverging and a converging bifurcation. The flow behavior of the CFL was investigated by using a high-speed video microscopy system where special attention was devoted to its behavior before the bifurcation and after the confluence of the microcahnnel. The numerical data was first obtained by using a manual tracking plugin and then analysed by an optimization technique using the genetic algorithm approach. The results show that for the majority of the cases the function that more closely resembles the CFL boundary is the trigonometric function.text/html2015-10-24T13:37:10+01:00http://www.webmedcentral.com/Prof. Maurizio BaroniSignificant changes detection in the follow-up of Retinal Pathologies through computer analysis of Optical Coherence Tomgraphy
http://www.webmedcentral.com/article_view/4995
Recently, Optical Coherence Tomograhy (OCT) is widely used to investigate retinal pathologies.Quantitative methods are needed to support qualitative evaluation carried on by medical specialists. Besides retinal thickness measurement, tomographic imaging allows to study macula morphology and tissue structure of retinal cellular layers. Pathological conditions are expected to alter this tissue appearance. Therefore, in the present work, image texture analysis is used to differenziate normal retinas from pathological ones as well as to detect significant changes in follow-up studies. Classical second order statistics, i.e. co-occurrence matrices, and a recent method, known as Local Binary Pattern (LBP), are applied to 25 normal subjects and to 34 patients, affected by vitreo-retinal interface traction syndrome or by retinal edema with various etiology. Both methods have shown a good capability to discriminate between normal and pathoplogical images: a few measured features exhibit signficant differences (p< 0.05) in inner retina, with a strong stability on varying method parameters. Then, a follow-up study was performed: 16 pairs of OCT images of pathological eyes, captured at different times, were selected out of a wider database of consecutive clinical examinations so that they were centered on the fovea, well aligned horizontally and without acquisition artifacts. Details of methods are discussed in the text. Results show a good agreement between clinical findings and the outcomes of co-occurrence, LBP and thickness analysis. Of particular interest is the analysis of critical pixels based on LBP, that allows to follow the pahology evolution in a simple, quantitative way.