The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The use of two powerful classification techniques (boosting and SVM) is explored for the segmentation of white-matter lesions in the MRI scans of human brain. Simple features are generated from proton density (PD) scans. Radial basis function (RBF) based Adaboost technique and support vector machines (SVM) are employed for this task. The classifiers are trained on severe, moderate and mild cases....
In vivo small animal imaging provides a powerful tool for the study of a variety of diseases. Magnetic resonance imaging (MRI) has become an established technology for the assessment of therapies. In this study, we used high-resolution MRI to evaluate polycystic kidney disease (PKD) in transgenic mice. We used a customized mouse coil to acquire serial MR images from both wide-type and transgenic PKD...
This paper describes an approach to fine scale non-rigid registration for mapping patterns of tissue volume loss in serial MRI studies of the brain. Specifically it addresses the important confound of diffuse tissue contrast changes which can influence local sub-voxel estimates of volume change. Such changes can be induced by neurodegenerative or neurodevelopmental processes, which not only modify...
A new thermal system for tumor treatment was designed to enhance the curative effects while minimizing invasion to the surrounding healthy tissue. This system includes LN2 cryosurgery and RF ablation, which can be used separately or simultaneously. A heat transfer model describing the thermal field during treatments was established. The SAR distribution was assumed to be resulted from an infinite...
Hyperthermia is one of the modalities for cancer treatment, utilizing the difference of thermal sensitivity between tumor and normal tissue. The authors have developed a coaxial-slot antenna for microwave hyperthermia. In this paper, calculated results of temperature distributions around the coaxial-slot antenna for the treatment of brain tumor and bile duct carcinoma are described
Cryopreservation of human embryonic stem cells is an important and unsolved problem. A computer-controlled programmable cooler is used in the preservation of ES cells. Several effects have been experimentally studied, which include the cooling rate, the seeding temperature , the terminative temperature before the sample is plunged into liquid nitrogen. It is found that the constitution of cryoprotective...
A novel liquid nitrogen cryoprobe is developed in the present study. The inlet, handle, the vapor-liquid separator and the heat transfer segment of the cryoprobe are designed to be detachable. This flexible construction provides many distinct features, such as good maneuverability, high safety and low cost. A new vapor-liquid separator is made to ensure the free flow of the liquid nitrogen and increase...
For accurate predictions of the tissue temperature distribution during cryosurgery a thermal model should incorporate the individual impact of large blood vessels. In presence of large vessel, configuring cryoprobe becomes very important because misplacement of cryoprobes may result in either inadequate cooling temperatures in the target tissue due to the heating nature of large vessels or undesired...
Long-term storage of engineered bio-artificial tissues is required to ensure the off-the-shelf availability to clinicians due to their long production cycle. Cryopreservation is likely the choice for long-term preservation. This study investigated the effects of dimethyl sulfoxide (DMSO) concentrations, cooling rates, cryoprotectant medium treatment methods and seeding on the cell viability of a tissue-engineered...
The self-assembling of DNA and cationic polymers are of interest for their biological applications. In this paper, the interaction of DNA with PAMAM was studied by agarose gel electrophoresis, size and zeta-potential measurements and circular dichroism (CD) spectroscopy. DNA was shown to form stable complexes with PAMAM by gel electrophoresis. The mean particle size of the complexes was in the range...
Nano-structured four branched, blocked star vector (BSV) was molecularly designed by iniferter-based photo-living radical copolymerization method of N,N-dimethylaminopropylacrylamide and then N,N-dimethylacrylamide from four dithiocarbamate-derivatized benzene for a novel gene delivery non-viral vector. The conjugated pDNA complexes were satisfactorily stable in the condition of the electrophoresis...
When conjugated to CdSe/ZnS nanocrystals (quantum dots), the nucleobase adenine and the neurotransmitter dopamine quench fluorescence emission from in a manner strongly dependent upon the size of the quantum dot. The degree of quenching serves to predict the efficiency with which the conjugates are able to enter living cells. Along with quenching, the presence of specific receptors on the cells is...
Micro/nano-particle drug delivery systems are being developed for improving therapeutic effects. However, most studies can only evaluate the delivery properties by indirectly measuring the pharmacokinetic changes of the drugs. It had been difficult to directly assay the drug carrier status and distribution in vivo. We described here a method using intravital microscopy to visualize individual drug...
Nanostructures of lysozyme molecules and lysozyme-nanogold conjugates were generated by atomic force microscopy in contact-, tapping- and force-distance-mode on mica in aqueous solution. In contact mode at high ionic strength, adjusted lysozyme concentration and lower loading force a monolayer of defined structure and orientation of lysozyme can be formed by the scan process of the tip. A lateral...
There are great challenges of developing high-throughput analytic tools in the post-genomic era. The microarray technology, as one of the most powerful high-throughput tools, has a lot of opportunities in meeting increasing enormous demands in the discovery of the molecular mechanisms of life systems. A number of the new concept microarrays will be developed and used in fundamental and medical researches...
The clinical management of skeletal trauma and disease relies on radiographic imaging to infer bone quality. However, bone strength does not necessarily correlate well with image intensity. There is a need for a safe and convenient way to measure bone strength in situ. This paper presents a new technique to directly measure bone strength in situ at a microlevel scale through a microelectromechanical...
We developed a new electroporation system, including a microchip and a logic circuit, and combining with the function of electrophoresis, which can site-specific enhancement of the gene concentration. We have demonstrated that the electroporation microchip could enhance and target in vitro gene transfection for cell lines. In this micro-device, the outer electrodes could provide the electrophoresis...
A neural sensor with novel structure and capable of double side recordings has been designed and fabricated using surface micromachining technique. Dry-etch benzocyclobutene (BCB) was selected as the substrate and packaging material for its excellent electrical, mechanical and thermal properties. Positive photoresist (AZ4620) was used as the sacrificial layer during the formation of backside recording...
A droplet-based microfluidic system was developed for biochemical assays of triglycerides and methanol as potential applications in medical rapid diagnostics and food safety. We present a novel platform to manipulate biology reaction droplets with features of self-moving, self-mixing, and self-positioning toward the detection spot. The driving force comes from the gradient of surface tension force...
This paper describes the detection of vesicular stomatitis virus using a novel capacitive immunosensor technology, whereby the respective antibodies for the antigens were used as a means for chemical detection on separate sensors. Devices were fabricated using standard etching and metal plating techniques, followed by immobilization of antibodies. Detection of antigen was performed by measuring voltage...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.