Radiochemical technique for intensification of underexposed autoradiographs

A radiochemical technique has been used to recover images of underexposed and developed autoradiographs. The underexposed image was radioactivated in a solution of [35S]thiourea, air-dried, and reexposed to Kodak NMC film which was developed and processed in a Kodak X-Omat processor. Features which were not discernible in the underexposed autoradiographs were well distinguished in the intensified autoradiograph.     

A simple procedure for obtaining autoradiographs of G-banded chromosomes

Chromosomal preparations from cells flash-labeled with ³H-dT were Giemsa-banded following trypsin digestion, allowed to air-dry, and then were coated with a layer of 1% Formvar. The slides were subsequently coated with radiographic emulsion (NTB2) and processed for autoradiography. The resulting chromosomes had distinct G-banding and radiographic labeling patterns. Chemographic grain formation in the emulsion, normally caused by Giemsa stain, was prevented by the film of Formvar, allowing a very low background grain level.     

Quantitative analysis of DNA array autoradiographs

DNA arrays and chips are powerful new tools for gene expression profiling. Current arrays contain hundreds or thousands of probes and large scale sequencing and screening projects will likely lead to the creation of global genomic arrays. DNA arrays and chips will be key in understanding how genes respond to specific changes of environment and will also greatly assist in drug discovery and molecular diagnostics. To facilitate widespread realization of the quantitative potential of this approach, we have designed procedures and software which facilitate analysis of autoradiography films with accuracy comparable to phosphorimaging devices. Algorithms designed for analysis of DNA array autoradiographs incorporate 3-D peak fitting of features on films and estimation of local backgrounds. This software has a flexible grid geometry and can be applied to different types of DNA arrays, including custom arrays.     

Improved method for processing autoradiographs of cells grown on multiwell plates

A modification of an established procedure for autoradiographic processing of cultured cells is described. This method eliminates the need for pipetting each individual well and also for cutting and dismantling the multiwell plate for slide preparation. In this procedure the entire plate can be processed as a single unit and the cells can be analyzed in situ, thus eliminating the time consuming pipetting and cutting procedures. Furthermore, the entire experiment can be filed without use of additional slides or storage boxes. Hence, this is a simpler, time conserving, and economical way to process large numbers of cultures for thymidine labeling indices.     

Extensive odontogenic cysts of varying histological structure in an x-ray film

As of now, a dental surgeon and a maxillofacial surgeon face a problem in choosing the optimal treatment of extensive cavitary masses in the maxillary bones. A detailed study of the characteristic x-ray manifestations of large jaw bone cavities makes it possible to give an insight into the pattern and extension rate of a destructive process, to choose the most optimal surgical treatment, and to yield more predictable results. The aim of this investigation was to analyze the morphological characteristics of large odontogenic cysts in the jaw bones and to reveal the main specific features of their x-ray picture in relation to their histological structure. An x-ray study determines the location, sizes, shape, and structure of the shadow of a cavity, its relation to the adjacent anatomic masses, as well as bone swelling, and preserved cortical laminae and facilitates the most correct presumptive diagnosis.     

Improved method for processing autoradiographs of cells grown on multiwell plates

Summary A modification of an established procedure for autoradiographic processing of cultured cells is described. This method eliminates the need for pipetting each individual well and also for cutting and dismantling the multiwell plate for slide preparation In this procedure the entire plate can be processed as a single unit and the cells can be analyzed in situ, thus eliminating the time consuming pipetting and cutting procedures. Furthermore, the entire experiment can be filed without use of additional slides or storage boxes. Hence, this is a simpler, time conserving, and economical way to process large numbers of cultures for thymidine labeling indices. This study was supported in part through a grant from the J. Graham Brown Regional Cancer Center, Louisville, Kentucky 40292.