Hybrid SPECT-CT and PET-CT imaging of differentiated thyroid carcinoma.

Hybrid imaging modalities such as radioiodine single photon emission CT with integrated CT ((131)I SPECT-CT) and 2-(fluorine-18)-fluoro-2-deoxy-D-glucose positron emission tomography with integrated CT (FDG PET-CT) allow the rapid and efficient fusion of functional and anatomic images, and provide diagnostic information that may influence management decisions in patients with differentiated thyroid carcinoma (DTC). Diagnostic localisation and therapy of these tumours are dependent upon their capacity to concentrate radioiodine ((131)I) via uptake through the sodium-iodide symporter and retention within the tumour. The prognosis for most patients with DTC is favourable, although controversy exists regarding the role of post-operative (131)I therapy in patients at low-risk for disease. Accurate identification of functional thyroid tissue (benign or malignant) using diagnostic (131)I planar scintigraphy complemented by SPECT-CT imaging enables the completion of post-operative staging and patient risk stratification prior to (131)I therapy administration. In patients with non-iodine-avid tumours (negative (131)I scan but elevated thyroglobulin indicative of persistent or recurrent disease), FDG PET-CT is used to identify tumours with enhanced glucose metabolism and to localise the source of thyroglobulin production. The CT component of this hybrid technology provides anatomic localisation of activity and allows CT-based attenuation correction of PET images. Images from 15 patients illustrate the applications of (131)I SPECT-CT and FDG PET-CT.

Fibrovascular ingrowth in porous ocular implants: the effect of material composition, porosity, growth factors, and coatings.

PURPOSE: Fibrovascular ingrowth into various porous ocular implants as a function of implant material composition, porosity, growth factors, and coatings was investigated in a pilot study in an animal model. METHODS: Eighty-one New Zealand white rabbits underwent unilateral enucleation and implantation with ocular implants composed of the following materials: coralline hydroxyapatite (HA) with 200-microm pores (HA200) or 500-microm pores (HA500), synthetic HA (synHA), and high-density porous polyethylene (PP). The HA200, HA500, and PP implants were implanted untreated or after treatment with recombinant human basic fibroblast growth factor (Rh-bFGF). Nine HA500 implants were implanted after coating with calcium sulfate (plaster of Paris) to provide a smooth outer surface. Implants were harvested at 1-, 2-, 4-, or 8-week intervals and were examined histologically. RESULTS: A significant difference was found between untreated HA500 and PP, with PP showing better ingrowth. There was no significant difference between untreated HA and PP, nor between untreated HA500 and synHA. Significant increases in ingrowth were found in HA200 compared with HA500, and in Rh-bFGF-treated implants compared with untreated controls. The calcium sulfate-coated implants showed less vascularization compared with the uncoated implants, although the difference was not significant. CONCLUSIONS: Fibrovascular ingrowth occurred earlier in HA200 implants than in HA500 implants, and was enhanced when implants were treated with Rh-bFGF.

Effect of aflatoxin B1-8,9-epoxide-DNA adducts on transcription of a supF gene fragment.

A linearized template, obtained from the vector pGEM-3Zf(+) containing a supF gene fragment, was treated with aflatoxin B1-8,9-epoxide (AFB1 epoxide) and transcription in vitro was then studied. The template functions of both strands of the supF gene were similarly inhibited as shown by transcription with both T7 and SP6 RNA polymerases. This inhibition was dose-dependent and affected the elongation step more extensively than the initiation step. Gel electrophoretic analysis of RNA formed by T7 RNA polymerase indicated that template treated with different AFB1 epoxide doses yielded the same three major truncated RNA fragments. Sequence analysis showed that these major sites of RNA truncation occurred in the vicinity of adjacent guanine residues in the template.

Bail-out directional atherectomy for abrupt coronary artery occlusion following conventional angioplasty.

Abrupt coronary occlusion following conventional balloon angioplasty (PTCA) remains a serious complication afflicting up to 10% of patients. Although repeat PTCA for prolonged durations can restore blood flow in approximately 50% of patients, if this technique fails, the patient is generally referred for emergent coronary bypass surgery. In this report, we describe the use of directional coronary atherectomy (DCA) as a bail-out technique on 16 patients (17 lesions) undergoing angioplasty who demonstrated a flow limiting dissection and clinical evidence of ongoing ischemia following the procedure which could not be reversed with repeat dilatation (mean 3.5 inflations) at prolonged balloon inflations (mean 6.9 min). Ten of these patients presented to the hospital with a diagnosis of unstable angina and the remaining patients were admitted with acute myocardial infarction. The majority of the incidences of abrupt occlusion (83%) occurred while the patient was still in the cardiac catheterization laboratory. Successful rescue atherectomy was achieved in 15 of the target arteries (88%). In two patients, this technique failed to stabilize the artery and emergent coronary bypass surgery was performed. A complication related to the bail-out procedure developed in three of the successfully treated patients during the same hospitalization. Two patients experienced recurrent abrupt occlusion which was successfully treated with a repeat bail-out atherectomy procedure and one patient developed a non Q wave myocardial infarction. All patients were followed clinically for a mean interval of 9.93 months. Ten patients (71%) remained free of symptoms and cardiovascular events for this period. Stress electrocardiography was performed on eleven (79%) of the successfully treated patients and in no case was ischemia demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)

P300, probability, and introverted/extroverted personality types.

Extreme introverted and extroverted subject groups (n = 24 each) containing equal numbers of male and females were assessed with the P300 (P3) component of the event-related potential (ERP). A two-tone auditory discrimination task in which the probability of the target stimulus varied systematically in different conditions (.20, .40, .60, .80) was used to elicit the ERPs. The P3 amplitude demonstrated a significant interaction between personality type, probability, and subject gender and was generally smaller for introverts than for extroverts. Female subjects tended to have larger overall P3 components than male subjects. P3 latency was not affected by the personality variable. The results support previous findings for ERP differences between introverts and extroverts and suggest that personality type differentially influences target stimulus probability effects. The findings are discussed in terms of individual differences in cortical activity on P3 amplitude and personality measures.

The effect of predilatation on coronary angioplasty-induced vessel wall injury.

Fifty-four patients presenting with stenotic lesions in a major coronary artery visually estimated by diagnostic angiography to be greater than 90% but less than 100% were randomized to one of two angioplasty regimens, predilatation (group 1) or no predilatation (group 2). In group 1, the artery was initially dilated with a 2 mm balloon followed by a balloon that was considered by the operator to be the definitive size to fully dilate the target vessel. In group 2, the artery was dilated with a balloon deemed the definitive size to complete the angioplasty procedure. There were no statistical differences between groups with respect to age, sex, history of unstable angina, or prior acute myocardial infarction. There were also no significant differences in the angiographic characteristics of the coronary lesions including artery location, lesion length, concentric or eccentric morphology, tubular versus discrete stenosis, calcium in lesions, or lesions on a bend. Following angioplasty, luminal filling defects were present in 5% of the predilated group and in 9% of the nonpredilated group (p = NS). The incidence of luminal border haziness at the dilatation site did not differ between groups, seven (35%) in group 1 versus eight (24%) in group 2. Angiographic evidence of a linear dissection at the angioplasty site was also similar between groups, one (5%) in group 1 versus five (15%) in group 2. Occlusive complications were witnessed in 10% of the predilated group and 12% of the nonpredilated group (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Recanalization of chronically occluded aortocoronary saphenous vein bypass grafts by extended infusion of urokinase: initial results and short-term clinical follow-up.

Chronic occlusion of saphenous vein aortocoronary bypass grafts is a common problem. Although percutaneous transluminal angioplasty of a saphenous vein with a stenotic lesion is feasible, angioplasty alone of a totally occluded vein graft yields uniformly poor results. Patients with such occlusion are often subjected to repeat aortocoronary bypass surgery. Experience with a new technique that allows angioplasty to be performed in a totally occluded saphenous vein bypass graft is reported. This technique utilizes infusion of prolonged low dose urokinase directly into the proximal portion of the occluded graft. Forty-six consecutive patients with 47 totally occluded grafts were studied. Patients had undergone end to side saphenous vein bypass grafting 1 to 13 (mean 7) years previously. All patients presented with new or worsening angina pectoris with ST-T changes or non-Q wave acute myocardial infarction and all had a totally occluded saphenous vein bypass graft. The new technique entailed the positioning of an angiographic catheter into the stub of the occluded graft and the advancement of an infusion wire into the graft. Patients were returned to the coronary care unit, where urokinase was delivered at a dose of 100,000 to 250,000 U/h. The total dose of urokinase ranged from 0.7 to 9.8 million U over 7.5 to 77 h (mean 31). After therapy, recanalization was seen in 37 (79%) of the 47 grafts. In 20 successfully treated patients, angiography was performed 1 to 24 (mean 11) months after treatment; 13 (65%) of these grafts were patent.(ABSTRACT TRUNCATED AT 250 WORDS)

Relative bioavailability and DNA adduct formation of benzo[a]pyrene and metabolites in the diet of the winter flounder.

1. Radiolabeled metabolites of the carcinogenic polycyclic aromatic hydrocarbon benzo[a]pyrene (BaP) were shown to be absorbed through the diet of the winter flounder, Pseudopleuronectes americanus. 2. Oral bioavailability of a mixture of naturally produced metabolites was significantly less than that of the parent BaP. 3. Oral bioavailability of a pure metabolite, BaP-7,8-dihydrodiol (7,8-D) was found to be similar to that of BaP. 4. Both metabolites and BaP formed DNA adducts in liver.

Pretesting a childbirth handbook.

The development of health education materials for pregnant women involves the work of knowledgeable and experienced health professionals, writers, editors, and artists. Frequently, these materials are also extensively reviewed by various experts and organizations prior to publication. Even with all this expert input and review, however, they can miss the mark if they are not deemed appropriate and acceptable by the audience for whom they were created. In developing a new booklet on childbirth, the New York State Department of Health wanted to ensure that the material would be read and used by pregnant women from various income and educational levels and racial and ethnic groups. Research was conducted by the department to pretest the booklet for its appropriateness for and acceptance by the target audience. Based on the reactions and suggestions from 89 women in eight focus groups, the booklet was revised extensively before being made available to the general public.

Structure of the human CR1 gene. Molecular basis of the structural and quantitative polymorphisms and identification of a new CR1-like allele.

Structural and quantitative polymorphisms have been described in human CR1. In the former, the S allotype is larger than the F allotype by 40-50 kD, the size of a long homologous repeat (LHR). In the latter, homozygotes for a 7.4-kb Hind III fragment express fourfold more CR1 per erythrocyte than do homozygotes for the allelic 6.9-kb restriction fragment. The basis for these genomic polymorphisms has been determined by restriction mapping the entire S allele and part of the F allele. The S allele is 158 kb and contains 5 LHRs of 20-30 kb, designated -A, -B/A, -B, -C, and -D, respectively, 5' to 3'. Extensive homology was found among the LHRs in their restriction maps, exon organization, and the coding and noncoding sequences. The presence of LHR-B/A in the S allele but not in the F allele accounts for the longer transcripts and polypeptide associated with the former allotype. At least 42 exons are present in the S allele, with distinct exons for the leader sequence, the transmembrane and cytoplasmic regions and most of the SCRs comprising the extracellular portion of CR1. Consistent with the mapping of the ligand binding site to the first two SCRs in each LHR, the second SCRs in LHR-A, -B/A, -B, and -C are encoded by two exons, reflecting a specialized function for this unit. The allelic 7.4/6.9-kb Hind III fragments extend from the 3' region of LHR-C to LHR-D. The 6.9-kb restriction fragment is the result of a new Hind III site generated by a single base change in the intron between the exons encoding the second SCR of LHR-D. A second cluster of genomic clones has been identified by hybridization to CR1 probes. Although they contain regions of hybridization to the cDNA and genomic probes derived from CR1, these cannot be overlapped with the structural gene owing to their distinct restriction maps. Three genomic polymorphisms previously identified by CR1 cDNA probes map to this region. These additional clones may represent part of a duplicated allele located nearby within the CR1 locus.

Immunoregulation by macrophages II. Separation of mouse peritoneal macrophages having tumoricidal and bactericidal activities and those secreting PGE and interleukin I.

Macrophage subpopulations having bactericidal or tumoricidal activities and secreting interleukin I (IL1) or prostaglandin E (PGE) were identified through primary or secondary infection with Salmonella enteritidis and separated by sedimentation velocity. Bactericidal activity was measured by [3H]-thymidine release from Listeria monocytogenes and tumoricidal activity by 51Cr-release from C-4 fibrosarcoma or P815 mastocytoma cells. Macrophages with bactericidal activity were distinguished from those with tumoricidal activity a) during secondary infection when cytolytic activity occurred only at days 1-4 post injection and bactericidal activity remained high throughout and b) after sedimentation velocity separation. Cytolysis was consistently greatest among adherent cells of low sedimentation velocity, whereas cells with bactericidal activity increased in size during the infection. Tumour cytostasis (inhibition and promotion of [3H]-thymidine uptake) differed from cytolysis in that the former was more prolonged during infection and was also detected among large cells. Secretion of immunoregulatory molecules PGE and IL1 occurred maximally among different macrophage subpopulations separated by sedimentation velocity and depending on the type of stimulus used in vitro. There was an inverse correlation between IL1 production and PGE production after stimulation with C3-zymosan or lipopolysaccharide (LPS). The development of immunity during infection may therefore be dependent upon the relative proportions of effector and regulatory macrophage subpopulations and the selective effects of environmental stimuli on these functions.