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J V Sullivan

Publications and source records attributed to J V Sullivan.

8 recordsLinked to original sources
PubMed1989

Toward a steady-state pore limit electrophoresis dimension for native proteins in two-dimensional polyacrylamide gel electrophoresis.

Polyacrylamide gel electrophoresis in linear pore gradients (4.8 to 48% T, 5% CBis) provides for migration arrest, in a practical sense, after about 5000 Vh for proteins of 290 and 450 kDa, but not for smaller proteins over 20,000 Vh. The arrest is not due to inadequate field strength nor is it caused by water redistribution within pore gradient gels. The possibility is being discussed that exponential pore gradients, and a higher or a lower degree of crosslinking suggested by the literature may be remedies for the present failure to arrest the migration of smaller proteins.

Acrylic Resins↗
PubMed1989

A thin-layer multistrip polyacrylamide gel electrophoresis apparatus for Ferguson plot analysis at the submicrogram load level.

A procedure was developed for casting thin-layer multistrip polyacrylamide gels and using them for the simultaneous gel electrophoresis at several gel (Ferguson plot analysis) at the sub-microgram load level, using silver staining, autoradiography and, potentially, blotting for detection. The lower viscosity of polymerization mixtures, compared to agarose gelation mixtures, required the redesign of the multistrip cassette with separation of channels by rubber gaskets and the application of a cassette press. The lowered viscosity also required addition of 35% sucrose and an increased rate of polymerization in application to multistrip gels formed on a common NetFix backing. The present design allows one to obtain Ferguson plots exemplified by those of 32P-labeled DNA followed by autoradiographic detection.

DNA↗
PubMed1989

A thin-layer multistrip agarose gel electrophoresis apparatus for Ferguson plot analysis at the sub-microgram load level.

A method for the simultaneous horizontal agarose gel electrophoresis on thin-layer strips of different gel concentrations was developed for the purpose of generating Ferguson plots at the sub-microgram load level. Seven independent gel strips on a common GelBond support were formed by filling channels created by a comb-shaped spacer (polycarbonate) in a vertical multistrip cassette. Electrophoresis on a horizontal Peltier-cooled surface employed commercial apparatus (E-C Apparatus Corp.) with a modified cover which is airtight and holds anodic and cathodic voltage measurement probes for each strip. The application of the apparatus to Ferguson plot analysis in a single experiment was exemplified on the RNA-containing turnip crinkle virus (TCV) at a load of 50 ng/gel strip, using an optimized silver staining method (a modification of a procedure of FMC Corp. BioProducts) for detection. Within the range of 3.5 to 12.5 V/cm, the plot was found to be independent of field strength. Mobility is also independent of the concentration of detergent (CHAPS) up to 10 mM.

Electrophoresis↗
PubMed1988

A motor-driven syringe-type gradient maker for forming immobilized pH gradient gels.

A motor driven gradient maker based on the commercial model (Jule Inc., Trumbull, CT) was designed for immobilized pH gradient gels to provide small volumes, rapid stirring and delivery, strict volume and temperature control and air exclusion. The device was constructed and by a convenient procedure yields highly reproducible gradients either in solution or on polyacrylamide gels.

Acrylic Resins↗
PubMed1986

Jet-directed catheter for interventional radiology.

A new catheter of dual lumen construction, suitable for clinical use, is capable of navigating acute vessel branches by selective retrojet fluid thrusts issuing from cowlings built into its distal sidewalls. Conventional radiopaque liquids can be used both to drive the system and to fluoroscopically locate its position relative to the vascular network. In vitro studies have shown the catheter to traverse straight vessels and negotiate difficult lateral turns over short radii in the process of entering progressively smaller branches. In vivo studies have verified these capabilities and suggest a means for embolizing tumors and arteriovenous malformations located at otherwise inaccessible regions. For arterial infusion of drugs to treat tumors, the turbulent jet action is utilized to enhance mixing within the blood stream to overcome the streaming phenomenon common to other catheters. The result is better distribution of the agent and increased opportunity for the drug to reach more of the tumor. The catheter system is undergoing clinical trials.

Angiography↗