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Ferritic ductile iron (DI) GJS 400 and high-silicon strengthened ductile irons (HSSDIs) with 3.5 and 4.5 wt% of silicon contents were produced with different cooling rates, and the microstructures were analyzed to find the main microstructure parameters. The Y-blocks GJS 400 presented good nodularity, while the heavy section GJS 400 presented some graphite degeneracy with a lower nodularity. The 3.5 wt% HSSDI shown a good nodularity, while with increasing silicon content to 4.5 wt%, significant graphite degeneracy occurred with the appearance of chunky graphite. Samples were tensile tested and the tensile data were analyzed through the physical-based constitutive Voce equation, and the Voce parameters were plotted to produce a matrix assessment diagram (MAD). Y-blocks and heavy section GJS 400 data lied on two distinct lines in MAD, and they had, however, positive and negative intercepts which meant indeed two contradictory plastic behaviors. The intercept of the best fitting line of the GJS 400 Y-blocks data was positive and so consistent with the physical meaning of Voce equation, while the intercept of the best fitting line of the GJS 400 heavy section data was negative, which meant an unexpected opposite plastic behavior. Same behavior was reported for the investigated HSSDIs, resulting in positive intercept of the best fitting line in MAD for the 3.5 wt% HSSDI data and negative intercept for the 4.5 wt% HSSDI data. The uniform strain energy density (SEDU) that is the area below the tensile flow curve up to the uniform strain, i.e., the strain where necking begins, was also investigated. SEDUresulted to be almost constant for all the GJS 400 Y-blocks tensile flow curves and 3.5 wt% HSSDI, which was typical of a sound material, while in GJS 400 heavy section and 4.5 wt% HSSDI, SEDUchanged significantly in a systematic way, indicating that metallurgical defects had affected the plastic behavior. So it was concluded that in the MAD the best fitting line of the tensile data with positive intercept was a possible indication of the material soundness, while the negative intercept was indication of defected material. The results suggested that the MAD analysis produced from tensile Voce parameters can be a useful and easy tool for industry not only to classify the production routes of DIs (Si content mainly and heat treatments), but also to identify possible microstructure poorness within a single DI grade.

Two hundreds and sixty red foxes, eighteen badgers and eight stone martens from north-eastern Italy were examined for zoonotic parasites by SCT, with particular attention to Trichinella sp. and Echinococcus multilocularis. No adult worms of E. multilocularis were observed in the intestine of red foxes or mustelids. Out of 223 fox faecal samples analysed by a commercial CA-ELISA, 5.8 % was positive to Echinococcus coproantigens. Trichinella sp. was detected by digestion of muscle in 1.2 % of examined foxes (2/172), but not in mustelids (0/11). Toxocara canis, responsible for human toxocarosis, resulted to be common in fox population (48.5 %). This parasite was found both in young (53.3 % of cubs and 61.9 % of sub-adults) and in adult animals (42.7 %). Other zoonotic parasites as Uncinaria stenocephala (52.3 %) and Trichuris vulpis (0.4 %) were detected in fox populations.

Summary: Two hundreds and sixty red foxes, eighteen badgers and eight stone martens from north-eastern Italy were examined for zoonotic parasites by SCT, with particular attention to Trichinella sp. and Echinococcus multilocularis. No adult worms of E. multilocularis were observed in the intestine of red foxes or mustelids. Out of 223 fox faecal samples analysed by a commercial CA-ELISA, 5.8 % was positive to Echinococcus coproantigens. Trichinella sp. was detected by digestion of muscle in 1.2 % of examined foxes (2/172), but not in mustelids (0/11). Toxocara canis, responsible for human toxocarosis, resulted to be common in fox population (48.5 %). This parasite was found both in young (53.3 % of cubs and 61.9 % of sub-adults) and in adult animals (42.7 %). Other zoonotic parasites as Uncinaria stenocephala (52.3 %) and Trichuris vulpis (0.4 %) were detected in fox populations.

La risonanza magnetica trova un campo di applicazione sempre maggiore a livello del sistema nervoso centrale e con l'affinarsi delle tecniche di aquisizione dell'immagine si dimostra sempre più precisa nello studio di trutture di piccole dimensioni quali sono i nervi cranici.Gli autori hanno preso in esame 20 casi per ciascun paio di nervi e per ciascun paio le sezioni in assiale, sagittale e coronale, al fine di ottenere un approfondimento delle conoscenze anatomiche in risonanza magnetica e soprattutto al fine di dare una quantificazione della visibilità di ogni nervo e di definire il piano di scansione più adeguato per la sua visualizzazione.Dai risultati emerge che la percentuale di visibilità è assoluta per i nervi di dimensioni più cospicue, quali sono i nervi ottico, trigemino, facciale ed acustico. La visibilità scende parzialmente per gli altri nervi, soprattutto per quanto riguarda il nervo ipoglosso.Il piano assiale risulta ottimale per lo studio del secondo, sesto, settimo, ottavo, nono, decimo, undicesimo e dodicesimo nervo cranico.Il nervo oculomotore risulta meglio valutabile sul piano sagittale mentre il piano coronale appare il più sensibile per una valutazione dei nervi trocleare e trigemino, nonostante quest'ultimo sia ottimamente rappresentato anche sul piano assiale.Secondo gli autori, una precisa conoscenza sulle possibilità ed al tempo stesso sui limiti della risonanza magnetica nella visualizzazione dei singoli nervi cranici consente di rendere più mirati gli esami a seconda delle situazioni cliniche che coinvolgono i nervi stessi; ciò può avere notevoli implicazioni dal punto di vista diagnostico e del bilancio anatomico.

The efficacy and safety of nonionic dimeric contrast media in subjects with impaired renal function is largely unknown. The present study was aimed at determining the risk of tubular nephrotoxicity in patients with mild to moderate renal insufficiency who underwent intravenous urography (IVU) with the nonionic dimeric contrast agent iodixanol (Visipaque, Nycomed Imaging, Oslo, Norway). In a double-blind protocol 64 patients (55 males; mean age 68.3 years) with serum creatinine between 135 and 265 μmol/l who were to undergo IVU were randomized to receive iodixanol (a nonionic dimer) or iopromide (a nonionic monomer), 600 mg I/kg b. w. Renal function was evaluated before and 1 h, 6 h, 24 h, 48 h and 7 days after IVU with analysis of serum creatinine, urinary enzymes alanylaminopeptidase and N-acetyl-β-glucosaminidase, and urinary microproteins α-1-microglobulin and albumin. Renal function remained stable in both contrast medium groups during the follow-up period. No statistically significant differences were observed between the monomer and the dimer in terms of urinary enzyme and microprotein excretion or serum creatinine. Transient radiocontrast-induced nephropathy developed in 1 patient who had received iodixanol. The administration of the nonionic dimeric contrast medium iodixanol, or of the nonionic monomer iopromide, entailed a low nephrotoxic potential in patients with mild to moderate renal insufficiency undergoing excretory urography.

Twenty-six patients with a clinical diagnosis of spondylodiscitis were examined with non-contrast and contrast-enhanced MRI in order to define the contribution of gadolinium-DTPA (Gd-DTPA) and different pulse sequences, including a fat suppression sequence (SPIR). Spin echo (SE) T1-weighted images before and after Gd-DTPA injection and SE T2-weighted images were obtained in all patients. Twelve patients were also examined using the SPIR sequence following Gd-DTPA injection. Signal intensity and morphological features of the disc and vertebral lesions were then evaluated. The SE T1-weighted sequence with Gd-DTPA was very effective in showing the pathological changes at the level of the disc as an area of low signal intensity surrounded by a peripheral rim of enhancement in 24 of 26 cases (92%). This feature was not visible on non-enhanced images. As regards contiguous vertebral lesions this sequence was less informative, since in 8 of 26 cases (31%) the vertebral lesions became isointense and therefore not detectable. In 12 cases there was extension into the surrounding structures (spinal canal and/or paravertebral tissues). An enhanced SE T1-weighted sequence provided good anatomical definition of the extension of the infection in the spinal canal in all cases with this type of involvement (7 of 12). Regarding the 7 cases with paravertebral extension, no extension was visible in 1 case due to the reduced contrast with the surrounding fat following Gd-DTPA injection. The enhanced SPIR sequence was very effective, particularly in detecting the lesions in the vertebral bodies, avoiding the limitation of the enhanced SE T1-weighted sequence. The SPIR sequence was also effective in showing the extension within the spinal canal and the paravertebral fat. On the basis of our results the combination of a SE T1-weighted sequence without contrast and SPIR sequence with Gd-DTPA seems to be the best approach in cases of spondylodiscitis.

Meningeal cysts (MC) are rare extensions of the meninges and are diverticula of the spinal meningeal sac, nerve root sheath or arachnoid that contain cerebrospinal fluid (CSF). They communicate with the subarachnoid space (SAS). The aim of this study was to demonstrate the MRI findings and to emphasise the contribution of MRI to the diagnosis of this rare pathology. MRI findings were evaluated according to a new classification that divides MCs into extradural cysts without (type 1) or with (type 2) spinal nerve root fibres and intradural cysts (type 3). Because of its high contrast resolution MRI can distinguish the three types of MC. The use of the different levels of signal intensity of the cyst and CSF in T2-weighted images to distinguish communicating from non-communicating MCs is illustrated. This diagnostic sign exploitats the signal loss due to flow phenomena of CSF pulsations on ungated sequences to reveal the communication of the MC with the SAS. We recommend MRI as the most sensitive and specific modality for the study of MCs.

Computed tomography (CT) and magnetic resonance (MR) findings in two patients with Fahr disease are presented. The CT scan showed extensive high attenuation foci with an almost symmetrical distribution in the dentate nuclei of the cerebellum, pons, basal ganglia and white matter. MR signals of the high attenuation CT foci ranged from hyperintensity to hypointensity. A hypothetical model for CT and MR signals is proposed, based upon the chemical composition of the deposits in Fahr disease. In the authors opinion the term mineralisation is more appropriate for this disease. A pattern of the location and distribution of the mineral ions that participate in this disease is proposed and a functional evaluation of the brain tissue has been estimated. A predictive pattern for the further evolution of the disease is proposed.

Non-ionic dimers induce less diuresis than non-ionic monomers, resulting in increased opacification of the urinary tract in intravenous (i.v.) urography. This double blind, comparative, randomized, parallel trial compared the efficacy of iodixanol (non-ionic dimer) and iopromide (non-ionic monomer) in 100 patients with mild to moderate renal insufficiency (serum creatinine of 135 to 265 mumol l-1) who underwent i.v. urography. A total dose of 600 mgI kg-1 bw of iodixanol (320 mgI ml-1) or iopromide (300 mgI ml-1) was injected. Radiographs were blindly evaluated by three radiologists who analysed different parameters (renal border visualization, nephrogram density, calyceal filling and density, papillary blush detection, delineation of collecting ducts, renal pelvis opacification, visualization of ureters, bladder density, bladder distention). Densitometric evaluation on the renal pelvis and bladder was also performed. Iodixanol showed better filling and density of the calyces (p = 0.004), more frequent detection of papillary blush (p = 0.003) and better opacification of the renal pelvis (p = 0.006). No significant differences between the two contrast media were found in regard to other parameters. In conclusion, the results confirmed theoretical expectations. The non-ionic dimer iodixanol is to be preferred to a non-ionic monomer such as iopromide in i.v. urography on patients with impaired renal function.

Abstract.: The aims of this study were (a) to compare the MR appearance of normal articular cartilage in ex vivo MR imaging (MRI) and MR microscopy (MRM) images of disarticulated human femoral heads, (b) to evaluate by MRM the topographic variations in articular cartilage of disarticulated human femoral heads, and subsequently, (c) to compare MRM images with histology. Ten disarticulated femoral heads were examined. Magnetic resonance images were obtained using spin-echo (SE) and gradient-echo (GE) sequences. Microimages were acquired on cartilage–bone cylindrical plugs excised from four regions (superior, inferior, anterior, posterior) of one femoral head, using a modified SE sequence. Both MRI and MRM images were obtained before and after a 90 rotation of the specimen, around the axis perpendicular to the examined cartilage surface. Finally, MRM images were correlated with histology. A trilaminar appearance of articular cartilage was observed with MRI and with a greater detail with MRM. A good correlation between MRI and MRM features was demonstrated. Both MRI and MRM showed a loss of the trilaminar cartilage appearance after specimen rotation, with greater evidence on MRM images. Cartilage excised from the four regions of the femoral head showed a different thickness, being thickest in the samples excised from the superior site. The MRM technique confirms the trilaminar MRI appearance of human articular cartilage, showing good correlation with histology. The loss of the trilaminar appearance of articular cartilage induced by specimen rotation suggests that this feature is partially related to the collagen-fiber orientation within the different layers. The MRM technique also shows topographic variations in thickness of human articular cartilage.