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Labelled leukocytes for diagnosis of infectious diseases. Our experience in labelling and clinical usefulness
No full textBackground: To review our experience in infectious diseases diagnosis, using a simple labelling technique. Methods: We made 101 scans in 91 patients with suspected infectious diseases confirmed by clinical, histologic or cultural specimens; a clinical or instrumental follow-up was available for every patient. Patients were divided into four subgroups: A: Inflammatory Bowel Diseases; B: Septic Syndromes; C: Bone diseases; D: Others. We used 99mTc-HMPAO in 80 scans and 111In in 21.In 20/80 frozen and stored HMPAO was used. Results: 99mTc-HMPAO frozen and stored labelling yield was: 60%(SD15%), 99mTcHMPAO: 62(12)(p n.s.), 111In 75%(10%), (p<0.05). Frozen-stored HMPAO was sterile and apyrogen. 27 had positive scan without leukocytosis or neutrophilia. No correlation between leukocytosis or neutrophilia and yield was observed. Transit lung times ranged between 14-16 min without differences among three radiopharmaceuticals. In each Group and in the sample as a whole True Positive, False Positive, True Negative, False Negative, Sensitivity, Specificity and Accuracy, were calculated. In Group B and in the sample as a whole Predictive Positive Value and Negative Predictive Value were also evaluated.
Conclusions: Labelling yields and ''viability'' were good using the three radiopharmaceuticals; labelling procedure was simple and safe. Accuracy PPV, NPV, cost-effectiveness were good; 111In is the choice for diagnosis of bone and joint infections. Frozen-stored HMPAO should be introduced as a cost-saving labelling procedure in practice
Evaluation of different counting methods for use in radiochemical purity testing procedures for (99m)Tc-labelled radiopharmaceuticals
Get PDFThe efficiency and accuracy of different methods for quality control of radiopharmaceutical preparations for diagnostic purpose were studied. The radiochemical purity of 99mTc Tetrafosmin, 99mTc Exametazime, 99mTc Sestamibi and 99mTc Oxidronate was evaluated by different thin layer chromatography systems, followed by cutting of the strips into two or three sections and by the measurement of radioactivity distribution by dose calibrator or gamma counter. In addition, to confirm the accuracy of these routine procedures, the strips were cut into a number of micro-sections (14–25) and each of them evaluated by the gamma counter.
The three tested procedures gave similar results and revealed a good and comparable accuracy. The radioactivity measurement with the dose calibrator remains the most practicable because of the rapidity of execution
Geometry and bone mass in primary hyperparatiroidism assessed by peripheral quantitative Computed Tomography (rQCT)
No full textPURPOSE: Non-invasive measurement by peripheral quantitative computed tomography (pQCT) of bone geometry, biomechanics, and mineral content in patients (pts) with primary hyperparathyroidism (PHPT). MATERIALS AND METHODS: Total, trabecular and cortical mineral density (totBMD, cortBMD, trab BMD), bone geometrical properties (total area, trabecular area, cortical area, cortical/total area) and cortical thickness as biomechanical parameters, were assessed by pQCT at distal radius in 38 (32 F; 6 M) consecutive patients with PHPT (mean age: 62 yrs; range: 30-77). In a subgroup of 12 patients, bone mineral density (BMD) was also measured by means of dual X-ray absorptiometry (DXA) at the lumbar spine (L2-L4). RESULTS: Serum biochemical characteristics were: iPTH (269+/-214 pg/ml; range: 107-1438, normal: 30-65), Calcium (11.4+/-1.1 mg/dl; range: 10.6-13.5, normal: 8.1-10.4) and Alkaline Phosphatase (398+/- 392 U/L; range:173-1174, normal: 98-279). Compa-red with 87 healthy age-matched subjects, total, trabecular and cortical bone densities were reduced in all patients (TotBMD: 216+/-92 mg/cm(3) vs ctr 342+/-94, -37%, p<0.05; TrabBMD: 93+/-51 mg/cm(3) vs ctr 140+/-54, -34%, p <0.01; CorBMD: 711+/-178 mg/cm(3) vs ctr 802+/-175, -11%, p<0.02), such as cortical thickness (0.143+/-0.02 cm vs ctr 0.157+/-0.03, -9%, p<0.02). Among geometrical parameters, only cortical/total area was significant different in the two groups (0,29 vs 0.31; p<0.04). A strong correlation was found between peripheral trabecular bone density assessed by pQCT and axial bone mineral density measured by DXA at L2-L4 (r=0.80; p<0.01). CONCLUSIONS: pQCT measurements in PHPT showed: 1) osteopoenia in all bone compartments partly related to age and menopause; 2) reduced cortical density and cortical thickness consistent with "cancellization" of the inner cortex and lower ability of bone to absorb loading forces. DXA measurements showed osteopoenia also at the lumbar spine, a site rich in trabecular bone. PQCT allowing selective assessment of true volumetric cortical and trabecular bone density such as bone geometry, is proposable in clinical practice, in order to evaluate presurgical bone "status" and to monitor the response to parathyroidectomy
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Nuclear cardiology and echocardiography for the assessment of myocardial viability
No full textThe review aims to make a comparative analysis of the nuclear cardiology and echocardiographic approaches for the assessment of myocardial viability on the basis of the most recent literature. Preliminarily the most extensively used methods are described: 1) metabolic tracers, especially as regards FDG-F18 (quantitative uptake; mismatch FDG uptake/perfusion); 2) sarcolemmal integrity tracers (201Tl- with stress-redistribution- reinjection or with rest-redistribution protocols; rest MIBI 99mTc); 3) low dose dobutamine stress echocardiography (LDDSE) for the detection of residual contractility reserve. Global sensitivity values of thallium studies are reported to be similar to those of LDDSE, but in selected patients populations with akinetic or severely hypokinetic segments the LDDSE sensitivity seems to be significantly lower, when metabolic viability assessed by FDG studies is assumed as gold standard. According to the Authors' opinion thallium study with a protocol including a rest injestion can be considered at the moment the first choice for myocardial viability assessment because of its convenience, reproducibility, possibility of technical and interpretative standardization, amount of clinical and experimental validations. Anyway further clinical trials with adequate follow-up are necessary in order to define the scintigraphic and echocardiographic patterns that provide the best accuracy in the prediction of the post-revascularization clinical outcome
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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