Intraindividual comparison of 99mTc-labelled anti-SSEA-1 antigranulocyte antibody and 99mTc-HMPAO labelled white blood cells for the imaging of infection

Technetium-99m labelled antigranulocyte antibodies are ready to use and are sensitive and specific in the diagnosis of infectious diseases. ^99mTc-SSEA antigranulocyte antibodies have a very high affinity constant (K _d 10^–12 M) for human neutrophils (PMNs), and excellent imaging qualities with high target/background ratios. The aim of this study was to compare the diagnostic accuracy of the ^99mTc-anti-SSEA-1 monoclonal antibody (Mab) with that of ^99mTc-hexamethylpropylene amine oxime (HMPAO)-labelled white blood cells (WBCs). To this end, 17 patients with 23 proven infectious foci were examined with 555 MBq ^99mTc-anti-SSEA-1 MAb and with 370 MBq ^99mTc-HMPAO labelled autologous leucocytes within a period of 7 days. All the infections were confirmed by culture, biopsy, surgery and follow-up. Whole-body images and planar spot views with the antibody were performed at 1-h, 4-h and 24-h post injection; the biodistribution of the antibody was quantified, absorbed radiation doses were calculated and the diagnostic results were compared with the ^99mTc-HMPAO WBC images. Human anti-mouse antibody (HAMA) evaluation was performed in all patients before and 3 months after antibody injection. Blood was drawn at different times after ^99mTc-anti-SSEA-1 MAb injection to determine the amount of granulocyte-associated radioactivity and to calculate recovery. ^99mTc-anti-SSEA-1 MAb scintigraphy detected all 23 lesions, while 21 were detected with ^99mTc-HMPAO WBC scan. In this small group of patients, the sensitivity and specificity of ^99mTc-anti-SSEA-1 MAb scintigraphy were 95% and 96% respectively, as compared with 91% and 82% respectively for ^99mTc-HMPAO WBC scan. An increasing uptake of the injected activity in the lesion at different time points was indicative of high affinity and of specific PMN binding.There was no HAMA formation. In four of five patients investigated, a transient mild leukopenia was found at 15 min p.i.. There was increased uptake of the antibody in liver and spleen and normal uptake in kidneys and bone marrow.The estimated radiation doses for the whole body and the red bone marrow were 1.1×10^–2 cGy/37 MBq and 5.3×10^–2 cGy/37 MBq, respectively. The activity associated to the PMNs in vivo was 33.5%, 30.6%, 21.3% and 9% at 5, 15, 30 and 45 min. post-injection, respectively. It is councluded that use of ^99mTc-anti-SSEA-1 antigranulocyte antibodies demonstrates promising results comparable to those obtained with ^99mTc-labelled autologous WBCs. The ^99mTc-labelled MAb is ready to use, has excellent image qualities and a high target/background ratio. Received 16 October and in revised form 17 December 1997     

Hemorrhagic adrenal adenoma simulating myelolipoma: CT evaluation.

We present a hemorrhagic adrenal adenoma surrounding and encompassing adjacent retroperitoneal fat to simulate the appearance of a myelolipoma by CT. A well-defined fibrous capsule, punctate calcification, and several macroscopic foci of fat within the mass led to an erroneous preoperative diagnosis. Lesions displaying large amounts of soft tissue attenuation material in addition to fat preclude a confident diagnosis of myelolipoma and should undergo directed percutaneous needle biopsy or surgery.     

Neuropsychological dysfunction in patients with end-stage pulmonary disease: lung transplant evaluation.

There has been a relative absence of studies that have examined the neuropsychological profiles of potential lung transplant candidates. Neuropsychological data are presented for 134 patients with end-stage pulmonary disease who were being evaluated as potential candidates for lung transplantation. Neuropsychological test results indicated that a significantly greater proportion of the patients exhibited impaired performances on a number of Selective Reminding Test (SRT) tasks as compared to the expected population frequency distributions for these measures. The highest frequencies of impairment were observed on the SRT's Immediate Free Recall (46.43%), Long-term Retrieval (41.67%), and Consistent Long-term Retrieval (51.19%) variables. On the Minnesota Multiphasic Personality Inventory-2 (MMPI-2)/Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A), patients' mean clinical profile revealed elevations on Scales 1 (Hypochondriasis) and 3 (Conversion Hysteria). This profile indicated that they were experiencing an array of symptomatology ranging from somatic complaints to lethargy and fatigue, and that they may have been functioning at a reduced level of efficiency. Findings are discussed in light of patients' end-stage pulmonary disease and factors possibly contributing to their neuropsychological test performances. Implications for clinical practice and future research are also provided.     

Accuracy of diagnosis of benign skin lesions in hospital practice: a comparison of clinical and histological findings

Demand for surgical removal of presumed benign skin lesions is increasing. Our aim was to see whether the practice of sending every skin specimen for histological review is necessary in a hospital-based dermatology department. We first reviewed the histological findings of 1000 lesion removed between 1990 and 1992 where a firm clinical diagnosis of a benign melanocytic naevus (BM; n = 250). seborrhoeic keratosis (SK: n = 250). viral wan (VW; n =250) or skin tag ( n = 250) had been made. Next, we perused the original clinical diagnosis made for all histologically proven malignant melanomas (MM) between 1968 and 1993, to see whether they had been misdiagnosed as one of the above four common benign lesions. Histology confirmed the clinical diagnosis in 89% of presumed BM. 89% of presumed SK, 83% of presumed VW and 81% of presumed skin tags. Common causes of misdiagnosis were other benign lesions: 52% of incorrectly diagnosed BM were SK and 30% of incorrectly diagnosed SK were BM, while 38% of incorrectly diagnosed VW were SK. A total of seven malignant tumours (six basal cell carcinomas, one squamous, cell carcinoma) were misdiagnosed clinically, one as BM, three as VW, and two as SK, but no malignant lesions were mistakenly diagnosed as skin lags. Review of 238 histologically proven malignant melanomas revealed a prior clinical diagnosis of BM in 9% and SK in 0.8%, but none were clinically misdiagnosed us skin tags or VW. Hence, in a hospital setting, a firm clinical diagnosis of u skin tag did not lead to missed malignancy, and routine histological confirmation of these lesions appears unnecessary. However, in the case of BM and SK. and where clinical doubt exists, histological review remains essential.     

Prenatal ethanol exposure reduces phosphoinositide hydrolysis stimulated by quisqualate in rat cerebellar granule cell cultures

Prenatal ethanol exposure-induced alteration in poly-phosphoinositide (PPI) hydrolysis stimulated by excitatory amino acids (EAA) was studied in rat cerebellar granule cells previously labeled with [³H]myoinositol. The prenatal exposure to ethanol was achieved via maternal consumption of a Sustacal (chocolate flavored) liquid diet containing either 5% ethanol (w/v, 35% of calories) or isocaloric sucrose (pair-fed) substituted for ethanol from gestation d 11 until the day of parturition. The ionotropic glutamate receptor agonists,N-methyl-d-aspartate, kainate or (±)-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) (100 μM each) induced a two- to four-fold increase in PPI hydrolysis over the basal level, regardless of the liquid dietary treatment. Stimulation with quisqualate (QA), an agonist activating both metabotropic and ionotropic glutamate receptors, resulted in a much stronger and dose-dependent response in PPI hydrolysis and exposurein utero to ethanol significantly reduced this response. Tetrodotoxin, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), or (±)-3-(2-carboxypiperazine-4-yl)-propyl-1-phosphonic acid (CPP) had no effect on QA-stimulated PPI hydrolysis nor on the suppression of this hydrolysis by ethanol. Exposurein utero to ethanol did not affect PPI hydrolysis stimulated by a selective metabotropic glutamate receptor agonist, trans-(±)-1-amino-1,3-cyclopentanedicarboxylic acid (t-ACPD). Although the PPI hydrolysis stimulated byt-ACPD could be blocked by (RS)-α-methyl-4-carboxyphenylglycine (MCPG), an antagonist of the metabotropic glutamate receptor, MCPG was incapable of affecting QA-induced PPI hydrolysis and the suppressive effects of prenatal ethanol exposure on this hydrolysis. Taken together, the data suggest that the long-lasting suppressive effects of prenatal ethanol exposure on QA-stimulated PPI hydrolysis in cerebellar granule cell cultures is through a metabotropic QA receptor pathway that may be different from the one activated byt-ACPD.     

Self-replicating Semliki Forest virus RNA as recombinant vaccine

Recombinant RNA based on the Semliki Forest virus (SFV) replicon was used to express the nucleoprotein of influenza virus in mice. Two strategies were employed to deliver the RNA. In the first, recombinant RNA was packaged into infectious suicide SFV particles which were used directly for immunization. The second approach involved injection of in vitro-synthesized RNA directly into the quadriceps muscle. Both approaches resulted in the generation of humoral responses with high antibody titres. Immunization with suicide particles showed that a strong, class I-restricted cytotoxic T-cell response can be obtained using only 100 infectious units. We conclude that the self-replicative recombinant SFV RNA may be quite useful as a nucleic acid vaccine.