Adriano Piffanelli

Brain single-photon emission tomography with 99mTc-HMPAO in neuropsychiatric systemic lupus erythematosus: relations with EEG and MRI findings and clinical manifestations.

Central nervous system (CNS) involvement in patients with systemic lupus erythematosus (SLE) is often difficult to evaluate because of protean neuropsychiatric (NP) manifestations and lack of reliable diagnostic markers. In the reported study the role of single-photon emission tomography (SPET) with technetium-99m hexamethylpropylene amine oxime (HMPAO) in the evaluation of CNS involvement in SLE was assessed and the relations between SPET perfusion defects, EEG examination, magnetic resonance imaging (MRI) findings and clinical presentation were examined. Twenty SLE patients with different NP manifestations were studied. Multiple areas of hypoperfusion, especially in the territory of the middle cerebral artery, were demonstrated by SPET analysis in all 20 patients. The number of hypoperfused areas and the degree of were more marked in patients with multiple NP manifestations. MRI and EEG evaluations were positive for 14 of 18 and for 12 of 20 patients, respectively. In the patients with positive SPET and MRI, 87 MRI focal lesions and 63 hypoperfused areas were found, and for 51 of these 63 at least one MRI lesion was found in the same anatomical region. SPET examination of patients with a normal EEG showed fewer hypoperfused areas and a lower degree of asymmetry compared to patients with an abnormal EEG. SPET of patients with focal EEG abnormalities showed more hypoperfused areas (difference not statistically significant) and a higher AI than did SPET of the patients with diffuse EEG abnormalities. Seven of 11 anatomical regions with focal EEG abnormalities. Seven of 11 anatomical regions with focal EEG abnormalities had co-localized hypoperfused areas and in two of these seven no detectable MRI lesions were found. The analysis of SPET and NP manifestations showed that 12 of 20 patients had at least one positive correlation, always involving the areas with the highest AI. In total, 51/88 (58%) hypoperfused areas correlated with the MRI findings and 31/88 (35%) with NP manifestations; for seven of the latter no concurrent MRI lesions were detected in the same anatomical region. It is concluded that SPET study of brain perfusion is a sensitive method for the evaluation of CNS involvement in SLE; furthermore, it is able to reveal disease progression and the lesions most relevant at the time of evaluation, and can objectify those NP manifestations without detectable MRI abnormalities. Nevertheless, because of the sensitivity of MRI in detecting morphological lesions, a complete evaluation of CNS involvement should be performed, combining SPET with MRI.

Detection and dynamic localisation of estradiol-receptor complexes in intact target cells by immunofluorescence technique

The total binding capacity of the cell receptors and not only the fraction required to elicit physiological response was detected and it is shown that specific receptors filled by endogenous estradiol were detected along with the unfilled sites. Changing the temperature of the incubation media altered intracellular distribution of bound estradiol. Late nucleolar retention of estradiol was shown after its release from nuclear protein. This unexpected finding may be a key event. Tumor tissues were obtained from 40 primary breast cancers, 2 endometrial carcinomas, and 1 lung and 1 gastric cancer; 2 normal human spleens, 2 mouse livers, and 1 breast from a 5-month pregnant women were processed. Tissue samples were transferred to a cold flask containing phosphate-buffered balanced salt solution. Further details of preparation are given to show typical estradiol-target cells containing variable amounts of specific estradiol-receptors. For immunofluorescence staining and indirect technique was used to show the in situ estradiol localization. The fluorescence staining showed 3 patterns. Cells incubated in the cold mostly displayed a bright, homogeneously diffuse fluorescence of the cytoplasm with the nuclear area unstained. There were some negative cells. The 2nd pattern of fluorescence was shown by those incubated at room temperature. Cytoplasmic staining was more marked and nuclear areas showed bright-fluorescent light stippling. A 3rd staining pattern was seen after slow postincubation warming up to 37 degrees C when increased nuclear staining occurred. Some cells did not show any nuclear labeling despite the clear cytoplasmic fluorescence. Preparations of human spleen, nontarget tumors, or mouse liver had no fluorescent cells. All fluorescent stainings were prevented by preincubation and washing in media containing Nafoxidine and N-ethylmaleimide. Control experiments confirmed the immune specificity of the detection of estradiol. Breast tissue cells from a pregnant women showed moderate cytoplasmic and faint nuclear fluorescence before incubation with estradiol, after which cytoplasmic staining was reinforced. Cells from the premenstrual beast cancers sometimes showed fluorescence without exposure to estradiol.

An integrated PET-SPECT small animal imager: preliminary results

The authors have successfully built and characterised a small animal PET based on 4 rotating detectors with a spatial resolution <2 mm over its field of view and a sensitivity of 640 cps//spl mu/Ci at the centre. The scanner is based on four matrices of 400 YAP:Ce finger crystals (2/spl times/2/spl times/30 mm/sup 3/ each) coupled to Position Sensitive PhotoMultipliers (Hamamatsu R2486-06.) The authors have now applied two high resolution collimators to two opposite detectors, hence realising an integrated PET-SPECT scanner for small animals. The collimators are made of lead with 20 mm long, 0.6 mm hexagonal holes with 0.15 mm septa. The read-out and data acquisition system are handled by NIM-CAMAC standard electronics. The Field Of View (FOV) of the tomograph has a diameter of 4 cm and an axial length of 4 cm in both PET and SPECT configuration which is appropriate for mice and rat studies.

Chemotherapy versus tamoxifen versus chemotherapy plus tamoxifen in node-positive, oestrogen-receptor positive breast cancer patients. An update at 7 years of the 1st GROCTA (breast cancer adjuvant chemo-hormone therapy cooperative group) trial

504 evaluable node positive oestrogen receptor (ER) positive breast cancer patients were randomly allocated to receive either 5 years tamoxifen treatment or chemotherapy [six courses of cyclophosphamide, methotrexate and 5-fluorouracil (CMF) followed by 4 courses of epirubicin] or a combination of both treatments. At a median follow-up of 5 years tamoxifen appeared to be more effective than chemotherapy, the difference being highly significant in postmenopausal women. The addition of chemotherapy to tamoxifen was not able to significantly improve the results achieved by tamoxifen alone, irrespective of menopausal status. Trends were similar even after stratification for the number of involved nodes. The protective effect of tamoxifen in terms of reduction of the odds of death increased with time and no rebound phenomena on recurrence or death has occurred so far after the completion of tamoxifen treatment. Overall, the prognostic value of number of involved nodes and of progesterone receptor (PgR) status was confirmed by multivariate analysis. However, the predictive value of PgR was lost in patients receiving tamoxifen alone. Similarly, the degree of ER positivity was not predictive of the response to tamoxifen. Tamoxifen treatment should still be regarded as the gold standard for postmenopausal ER positive patients. In younger women the antioestrogen proved to be safe and at least as effective as chemotherapy. However, the analysis of the annual risks suggests that the concurrent or the sequential use of chemotherapy and tamoxifen might represent a more appropriate treatment for this patient subset, particularly for those with four or more involved nodes. Different cut-offs of ER and PgR assays from those we have arbitrarily employed in the present analysis should probably be used to select more properly the patients who can benefit from endocrine therapy.

A class of asymmetrical nitrido 99mTc heterocomplexes as heart imaging agents with improved biological properties.

Asymmetrical heterocomplexes containing a terminal technetium-nitrogen multiple bond coordinated to one diphosphine ligand (PNP) and one dithiocarbamate ligand (DBODC), were obtained through a simple two-step procedure under controlled conditions. The resulting complexes [99mTc(N)(PNP)(DBODC)]+ are monocationic, and possess a distorted square-pyramidal geometry where the Tc≡N multiple bond occupies an apical position and the diphosphine and dithiocarbamate ligands span the residual four coordination positions on the basal plane through the two phosphorus atoms and the two sulfur atoms, respectively. Biodistribution data in rats demonstrated that these complexes were rapidly extracted by the myocardium, and retained in this region for a prolonged time. After a few minutes post-injection, lung uptake became negligible, and liver washout was extremely rapid and quantitative. Analysis of heart/liver uptake ratios for these complexes revealed that their values increased exponentially in time, and after 60 min post-injection liver activity was almost completely eliminated into the intestine. Comparison with heart/liver ratios determined for 99mTc sestamibi and 99mTc tetrfosmin showed that values for these latter compounds were approximately 10 times lower than those measured for [99mTc(N)(PNP)(DBODC)]+ complexes at 60 min post-injection. In conclusion, the monocationic tracers [99mTc(N)(PNP)(DBODC)]+ exhibit high myocardial uptake in rats and dramatically high heart/lung and heart/liver ratios, suggesting that this novel class of perfusion agents could be conveniently employed to obtain heart images with superior imaging quality.

Use of a YAP:Ce matrix coupled to a position-sensitive photomultiplier for high resolution positron emission tomography

A new scintillation detector system has been designed for application in high resolution Positron Emission Tomography (PET). The detector is a bundle of small YAlO/sub 3/:Ce (YAP) crystals closely packed (0.2/spl times/0.2/spl times/3.0 cm/sup 3/), coupled to a position sensitive photomultiplier tube (PSPMT). The preliminary results obtained for spatial resolution, time resolution, energy resolution and efficiency of two such detectors working in coincidence are presented. These are 1.2 mm for the FWHM spatial resolution, 2.0 ns for the FWHM time resolution and 20% for the FWHM energy resolution at 511 keV. The measured efficiency is (44/spl plusmn/3)% with a 150 keV threshold and (20/spl plusmn/2)% with a 300 keV threshold.

Brain perfusion SPET and proton magnetic resonance spectroscopy in the evaluation of two systemic lupus erythematosus patients with mild neuropsychiatric manifestations

The diagnosis of central nervous system (CNS) involvement appears to be a major problem in systemic lupus erythematosus (SLE), especially when the clinical signs are non-specific or neuroimaging is unremarkable. Two SLE patients with mild neuropsychiatric manifestations were studied with magnetic resonance imaging (MRI), single photon emission tomography (SPET) and localized proton magnetic resonance spectroscopy (H-1 MRS). MRI was normal in both patients. SPET revealed areas of hypoperfusion in both patients. H-1 MRS demonstrated metabolic abnormalities in the regions corresponding to the hypoperfused areas. A correlation between H-1 MRS and SPET was noted: patients with mild neuropsychiatric SLE may have disturbances evident on SPET and H-1 MRS in the presence of normal anatomy on MRI, suggesting that CNS involvement in SLE has very strong physiological and neurometabolic components in individual patients.

Characterization of laboratory working standard for quality control of immunometric and radiometric estrogen receptor assays. Clinical evaluation on breast cancer biopsies. Italian Committee for Hormone Receptor Assays Standardization.

The objective of the study was to characterize a low-cost and reliable working standard material for quality control of estrogen receptor (ER) determination with dextran-coated charcoal (DCC) and enzyme immunoassay (EIA) methods. Human fibromatous uterine lyophilized cytosol demonstrated good characteristics of stability and applicability for this purpose. Eleven laboratories participated in the intralaboratory and interlaboratory quality control study, and they achieved slightly higher coefficients of variation for ER-EIA (interlaboratory, 37.7 %; intralaboratory, 22.9 %) than for ER-DCC (Interlaboratory, 24.2 %; intralaboratory, 15.7 %). There was an excellent correlation between ER results with ER-EIA and ER-DCC for 268 breast cancer biopsies. Quality assurance for ER assays using DCC techniques and immunometric methods with monoclonal antibodies (ER-EIA) can be set up with this available material of human origin to satisfy the characteristics of both techniques and the species specificity of monoclonal antibodies.

In vivo and in vitro immunofluorescent approach to the physiopathology of estradiol kinetics in target cells

Abstract A fluorescent antibody has been employed for investigating the estradiol intracellular kinetics in target cells. In vivo observations showed that in the very immature rats (5-day-old) the translocation in the nucleus of the cytoplasmic bound estradiol, seems impaired at the level of the nuclear membrane; while in older animals (30-day-old) a normal, predominantly nuclear localization of the estradiol was observed. In vitro studies allowed the demonstration of the specific binding of the estradiol to the cytoplasm, nuclear chromatin, chromosomes and nucleolus, in various experimental conditions. Some defects of the cytoplasmie uptake, translocation and nuclear binding of the estradiol, which might be relevant to the hormone-dependence, have been demonstrated in cells from human breast cancers.

Technetium-99m sestamibi leg scintigraphy for non-invasive assessment of propionyl-l-carnitine induced changes in skeletal muscle metabolism

Carnitine derivatives, such as propionyl-l-carnitine (PLC), have been shown to improve walking distance in patients with obstructive peripheral artery disease (PAOD). The aim of this study was to ascertain whether technetium-99m sestamibi leg scintigraphy may be a useful tool in the evaluation of changes in skeletal muscle metabolism induced by chronic therapy with PLC. Twenty patients with clinical and instrumental evidence of PAOD were randomly assigned to a 3-month period of therapy with either PLC or placebo. Rest99mTc-sestamibi leg scintigraphy and echo-Doppler sonography were performed on all subjects immediately before and upon completion of the treatment period. At the end of the protocol the following results were observed in patients who underwent PLC administration: (a) a significant increase in both thigh and calf99mTc-sestamibi uptake, in comparison with baseline values (P<0.001); (b) the absence of statistically significant modifications of Doppler blood flow indices of the lower limbs. In conclusion, after chronic administration of PLC, a significant increment in skeletal muscle uptake of99mTc-sestamibi was demonstrated without any apparent change in regional blood flow. This fact, if proven in further studies, may suggest a role for this tracer as a non-invasive probe of tissue bioenergetics.