Same-day computed tomography during arterial portography and delayed high-dose iodine computed tomography: an efficient approach to imaging potentially resectable liver tumours

Preoperative imaging in patients with potentially resectable liver tumours has traditionally been performed in specialized hepatobiliary centres. To assess the feasibility and value of establishing a same-day, pre-resectional hepatic imaging service, computed tomography during arterial portography (CTAP) and delayed high-dose iodine computed tomography (DICT) were used to examine patients considered suitable for curative hepatic resection. The study group comprised 27 patients (14 from hospitals not affiliated with a university and 13 from two university-affiliated hospitals) for whom pre-referral imaging showed tumour distribution amenable to resection. Among the patients from centres not affiliated with a university, seven had undergone ultrasonography (US) and equilibrium-phase CT, four had undergone US and unenhanced CT, two had undergone equilibrium-phase CT only and one had undergone bolus dynamic incremented CT (BDCT) only. For 12 of the patients coming from the university-affiliated centres, the pre-referral imaging had consisted of US and BDCT; the other had undergone US only. After CTAP and DICT, 20 (74%) of the 27 patients were reclassified as having unresectable disease: 7 (54%) of the 13 patients who had undergone BDCT before CTAP and DICT and 12 (92%) of the 13 patients who had undergone unenhanced or equilibrium-phase CT, as well as the patient who had undergone US only. By averting laparotomy in 20 of the patients, CTAP and DICT resulted in short-term health care savings of about $160,000. These findings suggest that BDCT was underused in the hospitals not affiliated with university centres.(ABSTRACT TRUNCATED AT 250 WORDS)     

Freeze-fracture examination of the plasma membrane of the cellular slime mould Polysphondylium pallidum during microcyst formation and germination

Freeze-fracture observations of the plasma membrane of the amoebae of the cellular slime mould Polysphondylium pallidum during encystment showed a rapid increase in the density of intramembrane particles, especially in the EF face. This density remained high during the formation of the microcyst wall and then fell abruptly to the much lower values typical of the resting microcyst. During germination there was a corresponding increase in intramembrane particle density which continued to a level typical of vegetative amoebae. These results are discussed in the light of recent biochemical studies of microcyst formation, cellulose biosynthesis and microcyst germination.     

Seven-pinhole emission tomography with thallium-201 in patients with prior myocardial infarction

Thirty-six patients with prior myocardial infarction, and 14 patients without, had myocardial imaging at rest using both seven-pinhole emission tomography and planar imaging with thallium-201. The sensitivity and specificity of the two approaches for the detection of prior myocardial infarction were compared. Qualitatively, planar imaging yielded sensitivities of 69% (25 of 36) and 80% (29 of 36) with Polaroid and video display formats, respectively. A semiquantitative analysis gave a sensitivity of 75% (27 of 36). Specificities for these three planar approaches were, respectively, 100% (14 of 14), 93% (13 of 14), and 71% (10 of 14) for the Polaroid, video, and semiquantitative analyses. Seven-pinhole tomography had a sensitivity of 83% (30 of 36) by qualitative or visual inspection and 86% (31 of 36) by semiquantitative analysis. Specificities by these two techniques were 71% (10 of 14) and 57% (8 of 14). There were no statistically significant differences in either sensitivity or specificity between the planar and tomographic approaches. Repeat seven-pinhole images were identical in 95% (46 of 48) of patients, showing that reproducibility was satisfactory. We conclude that the seven-pinhole tomographic approach has no advantage over standard planar imaging in the detection of prior myocardial infarction.     

Evaluation of rapid polarographic method for determining tocopherols in vegetable oils and oil-based products

A polarographic procedure for the determination of the tocopherols in vegetable oils was compared to a conventional gas-liquid chromatographic procedure. The polarographic method is 2-3 times more precise and more rapid, which is an important advantage for monitoring the nutritional value of processing conditions of vegetable oil-based products. Attempts to establish the validity of apparently slightly higher values for alpha- and gamma-tocopherols obtained by polarography has implicated the gas chromatography or derivative formation rather than the extensive prior manipulation of the sample for chromatography as the source of error. Essentially the same results were obtained for alpha-tocopherol, regardless of the technique used. However, more variable results which were product dependent were obtained for gamma- and delta-tocopherols when gas-liquid chromatography was used.