Radiation Therapy Oncology Group. Research Plan 2002-2006. Patient Advocacy Committee.
Explore the source record for details and available documents.
Forecasting↗
Biomedical subjects
P Kim
Publications and source records attributed to P Kim.
Unstable angina and non-ST-segment elevation myocardial infarction: perspectives on combination therapy.
We reviewed recent clinical data on the management of unstable angina and non-ST segment elevation myocardial infarction. We concentrated on the use of new therapies, particularly in combination with both older agents and other new methods, in order to present health care providers with an overview of available treatment options. The clinical trials reviewed herein provide strong evidence and proof of principle that combination therapies targeting 1) platelet function (aspirin, thienopyridines, and GP IIb/IIIa antagonists), 2) the coagulation cascade (unfractionated heparin and low-molecular-weight heparin), and 3) the physical characteristics of the active lesion (percutaneous intervention) reduce the risk of death or ischemic complications after thrombotic progression of coronary atherosclerosis.
Adenosine Diphosphate↗
Meeting highlights : highlights of the 49th scientific sessions of the american college of cardiology
Explore the source record for details and available documents.
Journal Article↗
Intramolecular Diels-Alder Reactions of Decatrienoates: Remote Stereocontrol and Conformational Activation(1).
The intramolecular Diels-Alder (IMDA) reactions of C(8)-substituted decatrienoates have been studied. The stereospecific formation of 11 via an endo-boat-9 transition state attests to the powerful directing influence of a C(8) substituent in the IMDA of decatrienoate. In addition, the contrasting observations that stereospecific 9 --> 11 occurs at room temperature while the nor-tert-butyl substrate (4a) requires 125 degrees C/5 h reaction conditions and produces a 60:40 mixture of diastereomers provide clear evidence that a bulky C(8) substituent is a powerful conformational activator of the IMDA.
Journal Article↗
Search for free fractional electric charge elementary particles using an automated millikan oil drop technique
We have carried out a direct search in bulk matter for free fractional electric charge elementary particles using the largest mass single sample ever studied-about 17.4 mg of silicone oil. The search used an improved and highly automated Millikan oil drop technique. No evidence for fractional charge particles was found. The concentration of particles with fractional charge more than 0. 16e ( e being the magnitude of the electron charge) from the nearest integer charge is less than 4.71x10(-22) particles per nucleon with 95% confidence.
Journal Article↗
Dendritic cells genetically engineered to express Fas ligand induce donor-specific hyporesponsiveness and prolong allograft survival.
Polarization of an immune response toward tolerance or immunity is dictated by the interactions between T cells and dendritic cells (DC), which in turn are modulated by the expression of distinct cell surface molecules, and the cytokine milieu in which these interactions are taking place. Genetic modification of DC with genes coding for specific immunoregulatory cell surface molecules and cytokines offers the potential of inhibiting immune responses by selectively targeting Ag-specific T cells. In this study, the immunomodulatory effects of transfecting murine bone marrow-derived DC with Fas ligand (FasL) were investigated. In this study, we show that FasL transfection of DC markedly augmented their capacity to induce apoptosis of Fas+ cells. FasL-transfected DC inhibited allogeneic MLR in vitro, and induced hyporesponsiveness to alloantigen in vivo. The induction of hyporesponsiveness was Ag specific and was dependent on the interaction between FasL on DC and Fas on T cells. Finally, we show that transfusion of FasL-DC significantly prolonged the survival of fully MHC-mismatched vascularized cardiac allografts. Our findings suggest that DC transduced with FasL may facilitate the development of Ag-specific unresponsiveness for the prevention of organ rejection. Moreover, they highlight the potential of genetically engineering DC to express other genes that affect immune responses.
Animals↗
Improved right ventricular function after intracoronary administration of a C1 esterase inhibitor in a right heart transplantation model.
OBJECTIVE: Myocardial injury from ischemia can be augmented after reperfusion due to proinflammatory events including complement activation, leukocyte adhesion, and release of various chemical mediators. It has been shown that intracoronary administration of a C1 esterase inhibitor (C1 INH) significantly reduces myocardial necrosis in an experimental model of ischemia. Our study addresses the question whether the most susceptible region of the heart for ischemic injury, the right ventricle (RV), can benefit from the protective effects of C1 esterase inhibition after transplantation. METHODS: To precisely control RV volume in vivo an isovolumic model was used in which the RV volume was regulated using an intracavity high compliance balloon inserted into donor hearts of domestic pigs (34+/-4 kg). After 4 h of ischemia, donor hearts were transplanted into recipient pigs (44+/-4 kg). Treatment groups, each with six animals, consisted of C1 INH treatment or control. After opening the cross clamp, the C1 INH group animals received 20 IU/kg body weight of C1 INH intracoronary over a 5 min period. The control animals received no drug therapy. The hearts were reperfused for 60 min, and thereafter the RV balloon volume was increased in 10 ml increments until RV failure occurred. These measurements were repeated after 120 min of reperfusion. RESULTS: There was no significant difference in maximal RV developed pressure between the two groups (after 1 h, 35.7+/-5.9 vs. 40.6+/-12.7 mm Hg; after 2 h, 41.5+/-10.7 vs. 46.3+/-15.2 mm Hg; for C1 INH and control animals, respectively). However, the RV could be loaded with a significantly higher volume after both 1 h (60.0+/-20.0 ml (C1 INH) vs. 46.7+/-13.7 ml (control) balloon volume, P<0.05), and 2 h of reperfusion (70.0+/-8.9 ml vs. 60.0+/-6.3 ml; C1 INH and control animals, respectively; P<0.05). CONCLUSIONS: Intracoronary administration of a C1 INH significantly improves right ventricular function in an experimental transplant model. Thus, inhibition of the classic complement cascade may be a promising therapeutic approach for effective protection of myocardium from reperfusion injury after transplantation.
Animals↗
Biological modification of the fatty acid group in an emulsan by supplementing fatty acids under conditions inhibiting fatty acid biosynthesis.
When the concentration of the antibiotic cerulenin was increased up to 3.0 mg/l in medium containing ethanol as a carbon source, the specific growth rate of Acinetobacter calcoaceticus and the fatty acid content of the emulsan decreased from 0.179 h(-1) and 13.9% to 0.015 h(-1) and 3.4%, respectively. The emulsifying activity in medium containing cerulenin decreased with increasing cerulenin concentration. In the culture containing 3.0 mg/l cerulenin, fatty acid biosynthesis was inhibited. Various fatty acids were added to this inhibitory culture as a second carbon source to modify the fatty acid group in the emulsan. When an odd-numbered fatty acid was added, the resulting emulsan was found to have other odd-numbered fatty acids that were not present originally. Among the emulsan produced from even-numbered fatty acids, the emulsan produced from myristic acid (C14) contained the greatest amount of the same-numbered fatty acids. When the amount of supplemental myristic acid was increased, the myristic acid content in the emulsan increased, but its emulsifying activity decreased.
Journal Article↗
Bioconversion of D-galactose into D-tagatose by expression of L-arabinose isomerase.
D-Tagatose is a potential bulking agent in food as a non-calorific sweetener. To produce D-tagatose from cheaper resources, plasmids harbouring the L-arabinose isomerase gene (araA) from Escherichia coli, Bacillus subtilis and Salmonella typhimurium were constructed because L-arabinose isomerase was suggested previously as an enzyme that mediates the bioconversion of galactose into tagatose as well as that of arabinose to ribulose. The constructed plasmids were named pTC101, pTC105 and pTC106, containing araA from E. coli, B. subtilis and S. typhimurium respectively. In the cultures of recombinant E. coli with pTC101, pTC105 and pTC106, tagatose was produced from galactose in 9.9, 7.1 and 6.9% yields respectively. The enzyme extract of E. coli with the plasmid pTC101 also converted galactose into tagatose with a 96.4% yield.
Aldose-Ketose Isomerases↗
Low-potassium dextran solution ameliorates reperfusion injury of the lung and protects surfactant function.
OBJECTIVE: This study was designed to compare the effect of lung preservation with low-potassium dextran solution and Euro-Collins solution on reperfusion injury and surfactant function by using an in situ model of warm ischemia. METHODS: The left lungs of 6 minipigs were selectively perfused with Euro-Collins solution. In an additional 6 animals low-potassium dextran solution was used for flush perfusion. After 90 minutes of warm ischemia, the lungs were reperfused, and the contralateral pulmonary artery and bronchus were clamped. Hemodynamic and respiratory measurements were obtained for 7 hours of reperfusion. Surface tension of bronchoalveolar lavage and surfactant small and large aggregates were determined before perfusion (right lung) and after 2 hours of reperfusion (left lung). RESULTS: In the group receiving Euro-Collins solution, right heart failure developed within 215 +/- 39 minutes of reperfusion. An increase in minimal surface tension (P =.03), surfactant small aggregates/large aggregates ratio (P =.003), and bronchoalveolar lavage protein content (P =.012) were found after 2 hours of reperfusion. In the group receiving low-potassium dextran solution, all minipigs survived (P =.0001). Dynamic lung compliance (P =.034) and oxygen tension/inspired oxygen fraction ratios were higher (P =. 0001). Lung water content was lower (P =.049). The increase of minimal surface tension (P =.02) and bronchoalveolar lavage protein concentration (P =.015) were significantly less. CONCLUSION: Preservation of the lung with Euro-Collins solution leads to a reduction of physical surfactant function during reperfusion. Low-potassium dextran solution protects surfactant function and metabolism, thereby reducing reperfusion injury of the lung.
Animals↗
Use of a surgical ruler intraoperatively to stabilize the everted upper lid.
Explore the source record for details and available documents.
Eyelids↗
[Spinal tumor, extradural tumor, intradural extramedullary and intramedullary tumor].
Explore the source record for details and available documents.
Dura Mater↗
Nanotube nanotweezers
Nanoscale electromechanical systems-nanotweezers-based on carbon nanotubes have been developed for manipulation and interrogation of nanostructures. Electrically conducting and mechanically robust carbon nanotubes were attached to independent electrodes fabricated on pulled glass micropipettes. Voltages applied to the electrodes closed and opened the free ends of the nanotubes, and this electromechanical response was simulated quantitatively using known nanotweezer structure and nanotube properties. The mechanical capabilities of the nanotweezers were demonstrated by grabbing and manipulating submicron clusters and nanowires. The conducting nanotube arms of the tweezers were also used for measuring the electrical properties of silicon carbide nanoclusters and gallium arsenide nanowires.
Journal Article↗
Published criteria for evaluating health related web sites: review.
OBJECTIVE: To review published criteria for specifically evaluating health related information on the world wide web, and to identify areas of consensus. DESIGN: Search of world wide web sites and peer reviewed medical journals for explicit criteria for evaluating health related information on the web, using Medline and Lexis-Nexis databases, and the following internet search engines: Yahoo!, Excite, Altavista, Webcrawler, HotBot, Infoseek, Magellan Internet Guide, and Lycos. Criteria were extracted and grouped into categories. RESULTS: 29 published rating tools and journal articles were identified that had explicit criteria for assessing health related web sites. Of the 165 criteria extracted from these tools and articles, 132 (80%) were grouped under one of 12 specific categories and 33 (20%) were grouped as miscellaneous because they lacked specificity or were unique. The most frequently cited criteria were those dealing with content, design and aesthetics of site, disclosure of authors, sponsors, or developers, currency of information (includes frequency of update, freshness, maintenance of site), authority of source, ease of use, and accessibility and availability. CONCLUSIONS: Results suggest that many authors agree on key criteria for evaluating health related web sites, and that efforts to develop consensus criteria may be helpful. The next step is to identify and assess a clear, simple set of consensus criteria that the general public can understand and use.
Evaluation Studies as Topic↗
Crosslinking characteristics of an injectable poly(propylene fumarate)/beta-tricalcium phosphate paste and mechanical properties of the crosslinked composite for use as a biodegradable bone cement.
We investigated the crosslinking characteristics of an injectable composite paste of poly(propylene fumarate) (PPF), N-vinyl pyrrolidinone (N-VP), benzoyl peroxide (BP), sodium chloride (NaCl), and beta-tricalcium phosphate (beta-TCP). We examined the effects of PPF molecular weight, N-VP/PPF ratio, BP/PPF ratio, and NaCl weight percent on the crosslinking temperature, heat release upon crosslinking, gel point, and the composite compressive strength and modulus. The maximum crosslinking temperature did not vary widely among formulations, with the absolute values falling between 38 degrees and 48 degrees C, which was much lower than that of 94 degrees C for poly(methyl methacrylate) bone cement controls tested under the same conditions. The total heat released upon crosslinking was decreased by an increase in PPF molecular weight and a decrease in N-VP/PPF ratio. The gel point was affected strongly by the PPF molecular weight, with a decrease in PPF molecular weight more rapidly leading to a gel point. An increase in initiator concentration had the same effect to a lesser degree. The time frame for curing was varied from 1-121 min, allowing the composite to be tailored to specific applications. The compressive strength and compressive modulus values increased with decreasing N-VP/PPF, increasing NaCl content, and increasing BP/PPF ratio. For all formulations, the compressive strength values fell between 1 and 12 MPa, and the compressive modulus values fell between 23 and 265 MPa. These data suggest that injectable PPF/beta-TCP pastes can be prepared with handling characteristics appropriate for clinical orthopedic applications and that the mechanical properties of the cured composites are suitable for trabecular bone replacement.
Biodegradation, Environmental↗
Early angiographic results after revascularization by minimally invasive direct coronary artery bypass (MIDCAB).
OBJECTIVE: Anastomosing the left anterior descending artery (LAD) by use of the internal mammary artery (IMA) via an anterior minithoracotomy represents the most commonly performed minimally invasive direct coronary artery bypass (MIDCAB). However, little is known about angiographic results beyond patency rates. METHODS: Therefore, a retrospective analysis of 205 consecutive control angiographies was performed evaluating anastomototic patency as well as the angiographic morphology of the left IMA and the LAD. RESULTS: The overall anastomotic patency rate was 98.0%. As a result of incomplete IMA preparation (6-15 cm) large side branches (n = 4), or an IMA course under tension (n = 6) were occasionally observed. Despite a tension-free course, the IMA appeared fixed to the chest wall without functional compromise in 21 cases. A restrictive thrombus formation occurred once, IMA dissection was not seen. Two of the grafts developed spasms. A distal IMA stenosis >50% was seen in five cases. Stenosis of the anastomosis (>50%) itself was found once, as well as unexpected malinsertation to diagonal branches (n = 4). Compared with preoperative angiograms, de novo stenoses of the LAD were assessed proximal (14< or =50%, 2>50%) and distal (15< or =50%, 2>50%) to the anastomosis. Elevation of the LAD out of the vascular bed was an additional finding (n = 12) in a few cases. CONCLUSIONS: The overall patency of MIDCAB-LAD-grafting appears to be equivalent to conventional IMA grafting to the LAD. Particular angiographic findings, however, may be directly associated to the applied surgical technique.
Adult↗
Quality of life of stroke survivors.
Adaptation to stroke requires complex, long-term change in stroke survivors' lives. This study aimed at identifying those factors that influence quality of life (QOL) of geriatric stroke survivors 1-3 years post-discharge. The objectives were: to describe the overall quality of life of stroke survivors; to examine the relationships between sociodemographic variables, neurological variables, functional status, social support, perceived health status, depression, and overall QOL; and to determine the best predictors of QOL. Data were collected on 50 stroke survivors using a cross-sectional design and standardized questionnaires, including the Quality of Life Index, the Functional Independence Measure, the Social Support Inventory for Stroke Survivors and the Centre for Epidemiologic Studies Depression Scale. The overall quality of life of the study participants was low. The most important predictors of QOL were depression, marital status, quality of social support, and functional status. Depression was the strongest predictor of QOL. By employing a multi-dimensional perspective, this study confirmed that adaptation to stroke involves much more than physical function. Thus, rehabilitation programs for this group would be more effective if they are based upon a holistic approach.
Activities of Daily Living↗
D1 dopamine receptor-induced cyclic AMP-dependent protein kinase phosphorylation and potentiation of striatal glutamate receptors.
Dopamine receptor activation regulates cyclic AMP levels and is critically involved in modulating neurotransmission in the striatum. Others have shown that alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA)-type glutamate receptor-mediated current is potentiated by cyclic AMP-dependent protein kinase (PKA) activation. We made whole-cell patch clamp recordings from cultured striatal neurons and tested whether D1-type dopamine receptor activation affected AMPA receptor-mediated currents. After a 5-min exposure to the D1 agonist SKF 81297 (1 microM), kainate-evoked current amplitude was enhanced in approximately 75% of cells to 121+/-2.5% of that recorded prior to addition of drug. This response was inhibited by the D1 antagonist SCH 23390 and mimicked by activators of PKA. Moreover, by western blot analysis using an antibody specific for the phosphorylated PKA site Ser845 of GluR1, we observed a marked increase in phosphorylated GluR1 following a 10-min exposure of striatal neurons to 1 microM SKF 81297. Our data demonstrate that activation of D1-type dopamine receptors on striatal neurons promotes phosphorylation of AMPA receptors by PKA as well as potentiation of current amplitude. These results elucidate one mechanism by which dopamine can modulate neurotransmission in the striatum.
Action Potentials↗