Biomedical subjects
Publications and source records attributed to T V Bell.
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PURPOSE: To identify imaging features at unenhanced helical computed tomography (CT) that help differentiate distal ureteral calculi from pelvic phleboliths. MATERIALS AND METHODS: Retrospective analysis was performed of 184 pelvic calcifications identified at unenhanced helical CT in 113 patients. The size, shape, and attenuation of each calcification were recorded in addition to the presence of a central lucency and the appearance of the adjacent soft tissues. With profile analysis, a graphic representation was generated of attenuation in each pixel along a line drawn through each calcification. RESULTS: Geometric configuration was seen in eight (21%) calculi but not in any phleboliths. Differences were significant (P < .0001) between the mean attenuation of calculi and that of phleboliths. Among phleboliths, none had a mean attenuation greater than 278 HU, 13 (9%) had a visible central lucency, 31 (21%) had a bifid peak at profile analysis, 30 (21%) had the "comet sign" (adjacent eccentric, tapering soft-tissue mass corresponding to the noncalcified portion of a pelvic vein), and three (2%) had the soft-tissue rim sign (edema of the ureteral wall). Among calculi, none had a central lucency, bifid peak, or comet sign, but 29 (76%) had the soft-tissue rim sign. CONCLUSION: Analysis of pelvic calcifications at unenhanced helical CT can help differentiate calculi from phleboliths.
Virtual cystoscopy was performed in 13 patients with hematuria and abnormal findings at conventional cystoscopy. Perspective volume-rendering algorithms were applied to helical computed tomographic data to generate interactive, intraluminal views of the bladder mucosa after insufflation of room air. At conventional cystoscopy, 29 masses appeared to arise from the bladder mucosa and two were hypertrophied median lobes of the prostate. At virtual cystoscopy, 30 masses arose from the bladder (one prostate mass was misinterpreted as an intrinsic bladder mass). Results at virtual cystoscopy were comparable to those at conventional cystoscopy but were obtained without the associated risks.
Epidermal cells produce an interleukin 1 (IL-1)-related molecule known as epidermal cell-derived thymocyte activating factor (ETAF). Given their similar physical and biologic properties, it was presumed that ETAF would share homology to known IL-1 sequences. A murine IL-1 alpha complimentary DNA (cDNA) probe hybridized with a 2.1 kb RNA from the murine keratinocyte cell line PAMM 212. Further, a 24-base synthetic IL-1 beta probe complementary to a region 700 bases from the putative 5'-end of human IL-1 beta hybridized with 2.7- and 1.6-kb RNAs in human keratinocytes, monocytes, and promyelocytic leukemia cells. Reverse transcripts primed with the IL-1 beta oligonucleotide revealed major first-strand cDNAs from human keratinocyte COLO-16 cell mRNA and human monocyte mRNA of about 700 bases, consistent with the expected cDNA from IL-1 beta. A partial library constructed from this cDNA contained clones that hybridized with the IL-1 beta oligonucleotide. The 750 bp-IL-1 beta-like cDNA clones were not identical to IL-1 beta as judged by restriction mapping and Northern analysis. These cDNA clones hybridized with the 1.6-kb keratinocyte mRNA but not to the 1.6-kb monocyte nor to the 2.7-kb mRNA. The 1.6-kb keratinocyte mRNA may encode a new IL-1-like species.