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J E Terrell

Publications and source records attributed to J E Terrell.

24 records · Page 2Linked to original sources
PubMed1997

Comparison of sinus computed tomography staging systems.

In an attempt to establish a standardized rating system for CT of the paranasal sinuses, the Committee on Rhinology and Paranasal Sinus Disease of the American Academy of Otolaryngology-Head and Neck Surgery instituted a protocol for the review of sinus CT scans at six international sites. Fifty identical scans were rated by four otolaryngologists at each site according to five established sinus CT staging systems. Twenty of 24 reviewers repeated the rating session at least 1 week later to determine intrarater variability. The number of CT scans that could not be classified by a particular rating system ranged from 1.3% to 5.5%. The range of intrarater agreement (kappa = 0.39 to 0.74) exceeded that of interrater agreement (kappa = 0.18 to 0.49). A skewed distribution of CT scans resulted in a system with high rater agreement but poor ability to differentiate among disease states. The use of a numeric rating system to assign a score to each scan produced a comprehensive and disease-sensitive system, but one with low rater agreement. A precise definition of mucosal thickening in terms of millimeters appeared to enhance the raters' ability to assign stage and improve a system's comprehensiveness and reproducibility. On the basis of these findings, recommendations are made for the use of CT rating systems to study clinical outcomes in patients with chronic sinusitis.

Humans↗
PubMed1996

Parotid gland sparing in patients undergoing bilateral head and neck irradiation: techniques and early results.

PURPOSE: To minimize xerostomia in patients receiving bilateral head and neck irradiation (RT) by using conformal RT planning to spare a significant volume of one parotid gland from radiation. METHODS AND MATERIALS: The study involved 15 patients with head and neck tumors in whom bilateral neck radiation was indicated. The major salivary glands and the targets (tumor, surgical bed, metastases to lymph nodes, and the locations of lymph nodes at risk for metastases) were outlined on axial computed tomography images. Beam's-eye view (BEV) displays were used to construct conformal beams that delivered the prescribed doses to the targets while sparing from direct radiation most of one parotid gland. The gland that was planned to be spared resided in the neck side that was judged in each patient to be at a lesser risk of metastatic disease. Major salivary gland flow rates and the responses to a subjective xerostomia questionnaire were assessed before, during, and after radiation. RESULTS: Radiation planning for patients with central oropharyngeal tumors required the generation of multiple axial nonopposed beams. The resulting isodoses encompassed the targets, including the retropharyngeal nodes and the jugular nodes up to the base of skull bilaterally, while limiting the dose to the oral cavity, spinal cord, and one parotid gland. For patients with lateralized tumors, the ipsilateral neck side was treated up to the base of the skull; in the contralateral neck side, the treatment included the subdigastric nodes but excluded the jugular nodes at the base of the skull and most of the parotid gland. This was accomplished by a moderate gantry angle that was chosen using the BEV displays. Three months following the completion of radiation, the spared parotid glands retained on average 50% of their unstimulated and stimulated flows. In contrast, no saliva flow was measured from the unspared glands in any of the patients. Subjective xerostomia was absent, mild, or not different from that reported before radiation in 10 of 15 patients (67%). CONCLUSION: Partial parotid gland sparing is feasible by using three-dimensional planning in patients undergoing bilateral head and neck radiation. Approximately 50% of the saliva flow from the spared glands may be retained, and most patients thus treated have no or mild xerostomia in the early period after the completion of radiation. Whether tumor control and late complications are comparable to standard radiation will be assessed as more experience is gained.

Aged↗
PubMed1986

Insulin-like growth factor carrier proteins in neonatal and adult rat serum are immunologically different: demonstration using a new radioimmunoassay for the carrier protein from BRL-3A rat liver cells.

A carrier protein for insulin-like growth factors (IGFs) has been purified from serum-free medium conditioned by the Buffalo rat liver (BRL)-3A cell line and used to immunize rabbits. Purified carrier protein was 125I labeled and affinity purified on IGF-Sepharose. The major labeled protein had a mol wt of about 33,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (appropriate for the IGF carrier protein subunit) and gave a single predominant peak of radioactivity on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and acid-urea gel electrophoresis that was immunoprecipitated by immune serum and comigrated with unlabeled proteins that bind [125I] IGF. A RIA was developed using affinity purified [125I]carrier protein and immune serum. Tracer binding was inhibited only by preparations containing IGF carrier proteins, but not by unrelated proteins or by the IGFs themselves. Carrier proteins from BRL-3A cells gave equivalent strong reactivity either after dissociation of endogenous IGF or as an IGF-carrier protein complex. The antiserum effectively recognized the approximately 40,000 mol wt (Mr approximately 40,000) carrier protein from neonatal rat serum, both as a native complex and after acid stripping. It did not effectively recognize the Mr approximately 150,000 carrier protein from adult rat serum either as endogenous complex or after acid stripping. These results suggest that the Mr approximately 40,000 carrier protein of neonatal rat serum and the Mr approximately 40,000 binding subunit of the Mr approximately 150,000 carrier protein in adult rat serum are immunologically distinct. These antisera to the BRL-3A carrier protein should be useful tools with which to dissect the relationships between different carrier protein species and to study the regulation of IGF carrier protein gene expression.

Aging↗
PubMedDate not supplied

Isolation of a cDNA clone encoding rat insulin-like growth factor-II precursor.

Insulin-like growth factor-I (IGF-I) and IGF-II are mitogenic polypeptides of relative molecular mass (Mr) approximately 7,500 isolated from human plasma each containing four peptide domains in a single chain and identical at more than 60% of their amino acid loci. The B- and A-domains of the IGFs are approximately 40% identical to the B- and A-chains of human insulin. IGF-I and IGF-II have similar in vitro biological activities and receptor reactivity, but are immunologically distinct. IGF-I appears to mediate the effects of growth hormone on cartilage to promote skeletal growth whereas IGF-II may have a special role in fetal development and in the central nervous system. To investigate the in vivo role of IGF-II, we have studied IGF-II biosynthesis in the BRL-3A rat liver cell line. BRL-3A cells synthesize and secrete a 7,484 Mr protein 93% identical to human IGF-II and representing rat IGF-II (rIGF-II). Rat IGF-II is synthesized as a approximately 22,000 Mr prepro-rIGF-II (ref. 12) from 12 S poly(A)+mRNA. In addition, approximately 20,000 Mr pro-rIGF-II has been identified in lysates of biosynthetically labelled intact BRL-3A cells. We report here the isolation of an almost complete cDNA clone for rIGF-II. Our results indicate that pro-rIGF-II is synthesized as a 156 amino acid peptide precursor (17,619 Mr) containing mature rIGF-II 1-67 at its amino-terminus and an 89-residue carboxy-terminal peptide extension.

Amino Acid Sequence↗