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1.
Metallomics ; 7(2): 267-76, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25561341

RESUMO

The use of platinum, palladium and rhodium (Platinum Group Elements - PGEs) and the possibility of exposure to their ultratrace levels is increasing. In fact, the exponential development of metallic PGE-based nanoparticles (<100 nm in size) opens extraordinary perspectives in the areas of electrocatalysts and catalytic converters, magnetic nanopowders, polymer membranes, cancer therapy, coatings, plastics, nanofibres and textiles. Like other metal-based nanoparticles, exposure to PGEs nanoparticles may result in a release of ultratrace amounts of Pt, Pd, Rh ions in the body whose metabolic fate and toxicity still need to be evaluated. Furthermore, PGEs can act as allergic sensitizers by acting as haptens and inducing both type I and IV allergic reactions. In this work we studied the in vivo metabolic patterns of ultratrace levels of potent allergens and sensitizers PGE halogenated salts. (191)Pt, (103)Pd and (101m)Rh radioisotopes were prepared via cyclotron irradiation and used for radiolabelling Na2(191)PtCl4, Na2(103)PdCl4 and Na2(101m)RhCl6 salts. These anionic chlorocomplexes were intraperitoneally injected into rats (114 ng Pt kg(-1) bodyweight; 24 ng Pd kg(-1) b.w.; 16 ng Rh kg(-1) b.w.). At 16 h post-exposure, PGEs were poorly but significantly retained in all tissues analysed. Kidneys, spleen, adrenal gland, liver, pancreas and small intestine were the organs with the highest Pt, Pd, Rh concentrations. In the blood 30-35% of (103)Pd and (191)Pt and 10% of (101m)Rh were recovered in the plasma, mainly bound to albumin and to a less extent to transferrin. The hepatic and renal intracellular distribution showed the highest recovery of (191)Pt, (103)Pd and (101m)Rh in the nuclear fraction (liver) and in the cytosol (kidney). Chromatographic separation and ultrafiltration experiments on kidney and liver cytosols showed the strong ability of biochemical macromolecules to bind (191)Pt, (103)Pd and (101m)Rh, and being responsible for the retention of the three elements in the body. The link to macromolecules is the basis for the sensitizing capacity of PGEs.


Assuntos
Paládio/metabolismo , Platina/metabolismo , Ródio/metabolismo , Animais , Ânions , Proteínas Sanguíneas/metabolismo , Fracionamento Celular , Cromatografia em Gel , Cromatografia por Troca Iônica , Citosol/metabolismo , Injeções Intraperitoneais , Espaço Intracelular/metabolismo , Rim/metabolismo , Fígado/metabolismo , Masculino , Paládio/sangue , Platina/sangue , Ratos , Ratos Sprague-Dawley , Ródio/sangue , Frações Subcelulares/metabolismo , Distribuição Tecidual , Ultrafiltração
2.
J Ultrasound ; 17(2): 79-87, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24883130

RESUMO

Ankle sonography is one of the most commonly ordered examinations in the field of osteoarticular imaging, and it requires intimate knowledge of the anatomic structures that make up the joint. For practical purposes, the examination can be divided into four compartments, which are analyzed in this pictorial essay: the anterior compartment, which includes the tibialis anterior, extensor hallucis longus, and extensor digitorum longus tendons; the accessory peroneus tertius tendon; and the extensor retinaculum; the medial compartment (tibialis posterior, flexor digitorum longus, and flexor hallucis longus tendons; the flexor retinaculum; the medial collateral-or deltoid-ligament, and the neurovascular bundle); the lateral compartment (peroneus longus, peroneus brevis, and peroneus quartus tendons; superior and inferior peroneal retinacula, lateral collateral ligament); and the posterior compartment (Achilles tendon, plantaris tendon, Kagar's triangle, superficial, and deep retrocalcaneal bursae). Scanning techniques are briefly described to ensure optimal visualization of the various anatomic structures.

3.
J Ultrasound ; 15(3): 192-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23449849

RESUMO

Breast elastography is a new sonographic imaging technique which provides information on breast lesions in addition to conventional ultrasonography (US) and mammography. Elastography provides a noninvasive evaluation of the stiffness of a lesion. Today, two technical solutions are available for clinical use: strain elastography and shear wave elastography. Initial evaluations of these techniques in clinical trials suggest that they may substantially improve the possibility of differentiating benign from malignant breast lesions thereby limiting recourse to biopsy and considerably reducing the number of benign breast biopsy diagnoses. This article reviews the basics of this technique, how to perform the examination, image interpretation and the results of major clinical studies. Although elastography is easy to perform, training and technical knowledge are required in order to obtain images permitting a correct interpretation. This paper will highlight the technique and point out common pitfalls.Breast elastography is a new sonographic imaging technique which provides information on breast lesions in addition to conventional ultrasonography (US) and mammography. Elastography provides a noninvasive evaluation of the stiffness of a lesion. Today, two technical solutions are available for clinical use: strain elastography and shear wave elastography. Initial evaluations of these techniques in clinical trials suggest that they may substantially improve the possibility of differentiating benign from malignant breast lesions thereby limiting recourse to biopsy and considerably reducing the number of benign breast biopsy diagnoses. This article reviews the basics of this technique, how to perform the examination, image interpretation and the results of major clinical studies. Although elastography is easy to perform, training and technical knowledge are required in order to obtain images permitting a correct interpretation. This paper will highlight the technique and point out common pitfalls.

4.
J Ultrasound ; 15(3): 179-82, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23450671

RESUMO

The unroofed coronary sinus is a spectrum of cardiac anomalies in which part or all of the common wall between the coronary sinus and the left atrium is absent. Most cases are associated with anomalous systemic venous return, such as persistent left superior vena cava.The diagnosis of this lesion is important to the prognosis of the patient, but it is often difficult because of nonspecific clinical features.Here we report a case of a complete unroofed coronary sinus and persistent left superior vena cava discovered during a computed tomographic investigation for pulmonary hypertension.

5.
J Ultrasound ; 14(4): 196-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23396685

RESUMO

Scrotal trauma accounts for less than 1% of all trauma-related injuries. Traumatic injuries of the epididymis are extremely rare.Here we report a rare case of hematoma of the epididymis, diagnosed with US, in a 10-year-old boy after a sport injury.

6.
J Ultrasound ; 14(4): 182-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23396986

RESUMO

Breast biopsy consists in the collection of cells or tissue fragments from a breast lesion and their analysis by a pathologist. There are several types of breast biopsy defined on the basis of the type of needle used: fine-needle aspiration and biopsy performed with a spring-based needle. This article focuses on fine-needle aspiration performed under sonographic guidance.It is used mainly to assess cysts that appear to contain vegetations or blood or that are associated with symptoms; lesions and solid nodules that are not unequivocally benign; and axillary lymph nodes that appear suspicious on physical examination and/or sonography.In addition to distinguishing between benign and malignant lesions, ultrasound guided fine-needle aspiration also plays an important role in tumor grading and in immunocytochemical identifying specific tumor markers. This article describes the technique used and the possible causes of false negative and false positive findings. Despite its limitations, fine-needle aspiration has become a fundamental tool for the identification and preoperative management of malignant breast lesions.

7.
J Ultrasound ; 14(4): 205-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23396995

RESUMO

Testicular ischemia is a rare complication of inguinal hernia repair. It results from the injury to the vessels that course along the inguinal canal. Typically it is painful at the beginning and asymptomatic later. Ultrasonographic appearance and aspects of testicular ischemia result in diffusely hypoechoic and disomogeneous testis, with complete lack of intratesticular vascular signal on color-Doppler and cremasteric vessels hypertrophy in chronic cases.This report describes a testicular ischemia seen in a patient referred to because of hernia recurrence, without any sign or symptom of acute scrotum. Ultrasound examination showed the most frequent complications after inguinal hernia repair: both hernia recurrence and testicular ischemia.

8.
J Ultrasound ; 14(4): 216-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23397043

RESUMO

Down's syndrome is relatively common, and patients who are affected have an increased risk of developing acute leukemia, but not solid tumors. Studies performed in larger patient populations have shown that solid tumors, including lymphomas, are significantly less frequent in Down patients than in children and adults who are not Trisomy 21-affected.Testicular lymphomas are rare and extremely aggressive. Ultrasound (US) combined with color Doppler is essential in the diagnosis and evaluation of treatment results in these lesions. As they are very rare, it was decided to publish this mini-pictorial essay.

9.
Appl Radiat Isot ; 68(9): 1595-601, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20399107

RESUMO

Very high specific activity (A(S)) (186g)Re could be produced by either proton or deuteron cyclotron irradiation on highly enriched (186)W target in no-carrier-added (NCA) form, leading to a A(S) very close to the theoretical carrier free (CF) value of 6.88GBqmicrog(-1). Thick target yields (TTYs), obtained irradiating both thick metal W targets of natural isotopic composition and highly enriched pressed powdered (186)W targets, were measured at different particles energies taking into account high accuracy and precision on both yield and beam energy. The measurement of radionuclidic purity of (186g)Re obtained activating highly enriched (186)W by both p and d beams were also carried out and accurately compared. The excitation function as thin-target yields (tty, i.e. proportional to the reaction cross-sections) and the integrated TTYs for all Re (A=181, 182, 183, 184, 186 and their metastable levels), W and Ta co-produced radionuclides will be presented elsewhere in deep details.


Assuntos
Deutério/química , Deutério/efeitos da radiação , Marcação por Isótopo/métodos , Radioisótopos/química , Radioisótopos/efeitos da radiação , Rênio/química , Rênio/efeitos da radiação , Ciclotrons , Prótons , Doses de Radiação
10.
Med Phys ; 37(12): 6279-91, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21302784

RESUMO

PURPOSE: Computed tomography angiography (CTA) is increasingly used for the diagnosis of coronary artery disease (CAD). However, CTA is not commonly used for the assessment of ventricular and atrial function, although functional information extracted from CTA data is expected to improve the diagnostic value of the examination. In clinical practice, the extraction of ventricular and atrial functional information, such as stroke volume and ejection fraction, requires accurate delineation of cardiac chambers. In this paper, we investigated the accuracy and robustness of cardiac chamber delineation using a multiatlas based segmentation method on multicenter and multivendor CTA data. METHODS: A fully automatic multiatlas based method for segmenting the whole heart (i.e., the outer surface of the pericardium) and cardiac chambers from CTA data is presented and evaluated. In the segmentation approach, eight atlas images are registered to a new patient's CTA scan. The eight corresponding manually labeled images are then propagated and combined using a per voxel majority voting procedure, to obtain a cardiac segmentation. RESULTS: The method was evaluated on a multicenter/multivendor database, consisting of (1) a set of 1380 Siemens scans from 795 patients and (2) a set of 60 multivendor scans (Siemens, Philips, and GE) from different patients, acquired in six different institutions worldwide. A leave-one-out 3D quantitative validation was carried out on the eight atlas images; we obtained a mean surface-to-surface error of 0.94 +/- 1.12 mm and an average Dice coefficient of 0.93 was achieved. A 2D quantitative evaluation was performed on the 60 multivendor data sets. Here, we observed a mean surface-to-surface error of 1.26 +/- 1.25 mm and an average Dice coefficient of 0.91 was achieved. In addition to this quantitative evaluation, a large-scale 2D and 3D qualitative evaluation was performed on 1380 and 140 images, respectively. Experts evaluated that 49% of the 1380 images were very accurately segmented (below 1 mm error) and that 29% were accurately segmented (error between 1 and 3 mm), which demonstrates the robustness of the presented method. CONCLUSIONS: A fully automatic method for whole heart and cardiac chamber segmentation was presented and evaluated using multicenter/multivendor CTA data. The accuracy and robustness of the method were demonstrated by successfully applying the method to 1420 multicenter/ multivendor data sets.


Assuntos
Angiografia Coronária/métodos , Processamento de Imagem Assistida por Computador/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Humanos , Imageamento Tridimensional , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
11.
Appl Radiat Isot ; 64(9): 1001-5, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16500108

RESUMO

The short-lived (12.7h half-life) (64)Cu radioisotope is both a beta(+) and a beta(-) emitter. This property makes (64)Cu a promising candidate for novel medical applications, since it can be used simultaneously for therapeutic application of radiolabelled biomolecules and for diagnosis with PET. Following previous work on (64)Cu production by deuteron irradiation of natural zinc, we report here the production of this radioisotope by deuteron irradiation of enriched (64)Zn. In addition, yields of other radioisotopes such as (61)Cu, (67)Cu, (65)Zn, (69m)Zn, (66)Ga and (67)Ga, which were co-produced in this process, were also measured. The evaporation code ALICE-91 and the transport code SRIM 2003 were used to determine the excitation functions and the stopping power, respectively. All the nuclear reactions yielding the above-mentioned radioisotopes were taken into account in the calculations both for the natural and enriched Zn targets. The experimental and calculated yields were shown to be in reasonable agreement. The work was carried out at the Scanditronix MC-40 Cyclotron of the Institute for Health and Consumer Protection of the Joint Research Centre of the European Commission (Ispra site, Italy). The irradiations were carried out with 19.5 MeV deuterons, the maximum deuteron energy obtainable with the MC-40 cyclotron.


Assuntos
Radioisótopos de Cobre/química , Deutério , Zinco/efeitos da radiação , Ciclotrons
12.
Radiat Prot Dosimetry ; 115(1-4): 441-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16381763

RESUMO

Many regulatory agencies require that all building materials and industrial waste be tested for their naturally occurring radioactive material (NORM) concentrations before they can be used or thrown away. Usually the NORM concentrations of 40K, 232Th and 238U are measured by gamma-ray spectrometry using high-purity germanium or NaI(Tl) detectors. 40K is measured through its 1460.8 keV gamma line, which is mixed with 1459.2 keV line of 228Ac from the chain of 232Th. This fact ignored till now, requires a correction in the computation of 40K concentration. Although in many cases the error is <1%, there are cases where there have been higher errors. It should be emphasised that even if the correction in 40K concentration is large, the correction of the external dose index is negligible owing to the weighing factor being higher for 232Th than for 40K (by at least a factor of 10).


Assuntos
Manufaturas/análise , Radioisótopos de Potássio/análise , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Espectrometria gama/métodos , Raios gama , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Appl Radiat Isot ; 63(5-6): 621-31, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16055338

RESUMO

The production of no-carrier-added (NCA) alpha-emitter (211)At/(211g)Po radionuclides for high-LET targeted radiotherapy and immunoradiotherapy, through the (209)Bi(alpha,2n) reaction, together with the required wet radiochemistry and radioanalytical quality controls carried out at LASA is described, through dedicated irradiation experiments at the MC-40 cyclotron of JRC-Ispra. The amount of both the gamma-emitter (210)At and its long half-lived alpha-emitting daughter (210)Po is optimised and minimised by appropriate choice of energy and energy loss of alpha particle beam. The measured excitation functions for production of the main radioisotopic impurity (210)At-->(210)Po are compared with theoretical predictions from model calculations performed at ENEA.


Assuntos
Astato/química , Ciclotrons , Polônio/química , Astato/isolamento & purificação , Polônio/isolamento & purificação , Radioterapia , Espectrometria gama
14.
Appl Radiat Isot ; 60(1): 7-13, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14687630

RESUMO

The radioisotopes of ruthenium (103Ru and 106Ru) are abundant fission products and represent a radiological risk for the population in case of nuclear accidents. Few biokinetic studies have been performed on humans up to now and consequently the current model recommended by ICRP for ruthenium is derived mainly by extrapolation from animal data. The stable isotope 101Ru and proton activation analysis have been used to study the biokinetics of Ru in blood plasma samples taken during 8 studies in three healthy volunteers. The results obtained demonstrated that complexed Ru (in the form of citrate Ru(IV) complexes) is cleared from blood plasma very rapidly (characteristic half time of 17+/-2 min), while inorganic Ru remains longer in the systemic circulation, and is transferred to other organs and/or excreted with a biological half time of 23+/-2h. Good reproducibility of the clearance curves indicated no evidence of inter- or intra-individual variability when the same Ru solution was injected in repeated experiments to different subjects.


Assuntos
Rutênio/sangue , Rutênio/farmacocinética , Adulto , Humanos , Injeções Intravenosas , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Compostos Organometálicos/sangue , Compostos Organometálicos/farmacocinética , Compostos de Rutênio/sangue , Compostos de Rutênio/farmacocinética
15.
Radiat Prot Dosimetry ; 105(1-4): 209-12, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14526957

RESUMO

The interest in the biokinetics of ruthenium and zirconium in humans is justified by the potential radiological risk represented by their radionuclides. Only a few data related to the biokinetics of ruthenium and zirconium in humans are available and, accordingly, the biokinetic models currently recommended by the ICRP for these elements are mainly based on data from animal experiments. The use of stable isotopes as tracers, coupled with a proper analytical technique (nuclear activation analysis with protons) for their determination in biological samples, represents an ethically acceptable methodology for biokinetic investigations, being free from any radiation risk for the volunteer subjects. In this work, the results obtained in eight biokinetic investigations for ruthenium, conducted on a total of three healthy volunteers, and six for zirconium, performed on a total of three subjects, are presented and compared to the predictions of the ICRP models.


Assuntos
Modelos Biológicos , Radiometria/métodos , Radioisótopos de Rutênio/sangue , Radioisótopos de Rutênio/farmacocinética , Zircônio/sangue , Zircônio/farmacocinética , Administração Oral , Adulto , Simulação por Computador , Feminino , Humanos , Injeções Intravenosas , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Doses de Radiação , Técnica de Diluição de Radioisótopos , Radioisótopos/administração & dosagem , Radioisótopos/sangue , Radioisótopos/farmacocinética , Radioisótopos de Rutênio/administração & dosagem
18.
Pathologica ; 91(6): 453-8, 1999 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-10783641

RESUMO

OBJECTIVE: This experience shows the effectiveness of the cytological examination in the diagnosis of biliary and pancreatic neoplasm on samples obtained from Vater's papilla through endoscopic intestinal brushing. STUDY DESIGN: From June 1997 to October 1998, 28 patients, suffering from suspicious neoplasm of Vater's papilla or biliary system, were studied. Each sample was obtained through intestinal brushing during an Endoscopic Retrograde Colangio-Pancreatography (ERCP) and processed with the technique of direct smear stained with Papanicolaou's method. The sample was followed by the corresponding biopsy in 16 cases and by surgical specimens in 8 cases. RESULTS: 27 patients out of 28 were correctly classified by the intestinal brushing. The method carried out a positive predictive value of 100% and a sensitivity of 93%. The sensitivity of biopsy turned out to be 80%. CONCLUSIONS: The intestinal brushing is an effective method of diagnosis, which turned out to be relevant as a support and, in several cases, as a substitute of the biopsy. We think, therefore, that the brushing should be carried out whenever a lesion of the Vater's papilla or of the biliary system is suspected during an ERCP.


Assuntos
Ampola Hepatopancreática/patologia , Neoplasias dos Ductos Biliares/patologia , Neoplasias Pancreáticas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Colangiopancreatografia Retrógrada Endoscópica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade
19.
Biol Trace Elem Res ; 71-72: 209-22, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10676495

RESUMO

The concentrations (ng/m3) of more than 30 trace elements have been determined in the total air particulate matter and in the size-segregated fractions collected in urban, industrialized, and rural residential areas in northern Italy by means of a multistage inertial impactor with the PM10 inlet. All measurements have been carried out by instrumental neutron activation analysis, except for Pb and Cd, which have been determined by electrothermal atomic absorption spectroscopy. Analytical quality assurance procedures have been developed with special regard to blanks, reagents, and sampling. Total concentrations and the granulometric distribution found in the different locations are reported and compared.


Assuntos
Poluentes Atmosféricos/análise , Saúde da População Rural , Oligoelementos/análise , Saúde da População Urbana , Monitoramento Ambiental , Análise de Ativação de Nêutrons , Tamanho da Partícula , Respiração , Espectrofotometria Atômica
20.
J Pharmacol Exp Ther ; 285(1): 193-200, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9536010

RESUMO

Taking advantage of a standard assay on mouse LM cells (murine fibroblast-like cells), we found that several diaminic carbonates, a new class of organic compounds synthesized in our laboratories, were able to inhibit human tumor necrosis factor alpha (huTNFalpha)-induced cytotoxicity in a dose-dependent manner. Structure-function relationship studies indicated precise structural requirements for compounds being active as huTNFalpha inhibitors. ITF1779, one of the most active compounds in inhibiting huTNFalpha-induced cytotoxicity, was selected for further studies. In vitro experiments showed that ITF1779 inhibited not only huTNFalpha-induced cytotoxicity on LM cells but also another response of the same cells, interleukin-1-induced interleukin-6 production. Receptor-binding studies performed under nonequilibrium conditions and morphologic evidence of vacuole formation in cells treated with high concentrations of ITF1779 showed that the effects were strikingly similar to those of chloroquine, a lysosomotropic agent. Consistent with a mechanism of action of diaminic carbonates closely matching that of chloroquine are some structural similarities between the two classes of compounds, in particular their both being diprotic weak bases. Moreover, ITF1779 was shown to be active in vivo because it afforded protection against lipopolysaccharide-induced shock in mice, a systemic inflammatory response crucially dependent on tumor necrosis factoralpha production.


Assuntos
Anti-Inflamatórios/farmacologia , Butilaminas/farmacologia , Carbonatos/farmacologia , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Animais , Células Cultivadas/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Humanos , Interleucina-1/farmacologia , Interleucina-6/biossíntese , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos BALB C , Choque Séptico/induzido quimicamente , Choque Séptico/prevenção & controle , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
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