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Introduction: The analysis of saw mark characteristics on bones can provide useful information about the type of saw used to produce the injury/mark. This study aims at testing micro-computed tomography (micro-CT) analysis of false start saw marks produced on human bones by different types of saws in order to correlate the metrical characteristics of the saw with those of the mark. Material and Methods: This study was performed on 40 human defleshed metacarpal, metatarsal and phalanx bones, collected from individuals who donated their body to the University of Padua for research purposes. The saw marks examined in this study were generated using 5 new saws, including: 3 saws with alternating set and different teeth per inch (TPI; 5, 8 and 10, respectively) and 2 saws with wavy set and different TPI (18 and 24, respectively). All marks were inflicted manually by the same operator, holding the saw perpendicularly to the long axis of the bone, applying a single unidirectional stroke with an excursion of 15 cm in length, in order to simulate a false start. Each bone sample was scanned by a Skyscan 1172 HR micro-CT (Skyscan, Aartselaar, Belgium) with the following parameters: 14 μm isotropic voxel size, 51 Kv, 194 uA, exposition time 6050 ms, rotation step 0.7, frame averaging 2, 1280 x 1024 pixel Field of View. Reconstructions were performed by N-Recon Software (Skyscan, Aartslaar Belgium), subsequently, the bitmap files were converted in DICOM using the DICOM Converter® Software. Osirix (Open Source Software, Version 7.0.1) was used to perform all the measurements and elaborate the multiplanar (MPR) and 3D volumetric reconstructions. For each bone sample, on the MPR images, the following features were assessed: number of isolated marks on each bone, shape of the mark on the sagittal plane (rectangular or triangular), maximal depth and height measured on the sagittal plane and presence of metal residues. Results: All saw marks were detected by micro-CT. Marks produced by saws with 5, 8 and 10 TPI showed two incisions with different shapes and dimensions, which were in some cases in continuity one with the other. Saw marks produced by saws with 18 and 24 TPI showed a single mark with rectangular shape and different dimensions. Metallic residues were observed in several cases. Conclusions: The preliminary results of the study suggest that micro-CT could be a useful tool for the analysis of saw marks produced on human bones. The possibility to assess the morphometric features of each lesion indicates that this technique might provide accurate and precise information about the characteristics of the type of saw used. However, further studies including a wider number of samples and using a higher variety of cutting weapons need to be performed to fully assess the potentiality of the presented radiological technique.

Background. A review of the literature reveals many cases involving gunshot wounds altered by fire. The burning process can cause severe morphostructural changes (such as splits, shrinkage, crumbling) that are capable of altering or obscuring gunshot residue evidence and of producing post-mortem heat lesions on the skin, similar to gunshot wounds. Aim of the study. The present study is aimed at evaluating and comparing the amount and differential distribution of gunshot residue (GSR) through the analysis of unburned and burned gunshot wounds, performed with a microcomputed tomography (Micro-CT) technique. Materials and methods. Thirty-six experimental shootings at three different firing distances (5,15 and 30 cm) and 12 stab wounds, produced by a pointed instrument, were inflicted on human calves. Twenty-four specimens (6 for each tested distance and 6 for the stab wounds) were formalin-fixed, while the other were placed inside a wood-burning stove (4 minutes, 400°C), before formalin fixation. Each entrance and exit wound was sampled, cutting a parallelepiped specimen (1 x 1 x 2,5 cm) of epidermis, dermis and subcutaneous fat, surrounding and including the substance defect. All specimens were scanned using a Skyscan 1172 High Resolution Micro-CT, analyzing only particles with a density higher than 1000 HU, assumed to be GSR. Each sample was stained with hematoxylin–eosin and examined with a Leica DM-4000B optical microscope. Statistical analyses were performed using a two-way- and a one-way-ANOVA test. Results. As the unburned samples were easily recognizable, the visual and histological investigation on the burned samples cannot distinguish the entrance gunshot wounds from the stab wounds or the exit wounds. In the unburned specimens the Micro-CT analysis detected particles with a density higher than 1000 HU on the epidermis layer around the hole and on the dermis layer. In burned samples the GSR was detected only in the dermis layer. In burned and unburned samples GSR particles were not detected in either the stab wounds or in the exit holes. Statistical analysis reveals that GSR percentage was in inverse ratio to firing distance with a non-linear fashion and was abated after the burning process. Discussion and Conclusions. Micro-CT is a useful screening for the study of charred wounds, capable of distinguishing gunshot entrance wounds from the exit wounds or other similar lesions. Further examinations, even in different experimental conditions (temperature, time of exposure), are necessary in order to corroborate the correlation between firing distance and GSR percentage on samples damaged by fire.

It is unclear whether revascularization of renal artery stenosis (RAS) by means of percutaneous renal angioplasty and stenting (PTRAS) is advantageous over optimal medical therapy. Hence, we designed a randomized clinical trial based on an optimized patient selection strategy and hard experimental endpoints. Primary objective of this study is to determine whether PTRAS is superior or equivalent to optimal medical treatment for preserving glomerular filtration rate (GFR) in the ischemic kidney as assessed by 99mTcDTPA sequential renal scintiscan. Secondary objectives of this study are to establish whether the two treatments are equivalent in lowering blood pressure, preserving overall renal function and regressing target organ damage, preventing cardiovascular events and improving quality of life. The study is designed as a prospective multicentre randomized, un-blinded two-arm study. Eligible patients will have clinical and angio-CT evidence of RAS. Inclusion criteria is RAS affecting the main renal artery or its major branches either >70% or, if

Great attention has been placed on the possibility of distinguishing Th1 from Th2 cells on the basis of differential expression of surface receptors. We have recently shown that the differential expression of the IL-12Rβ2 chain in Th1 and Th2 cells, as measured at the mRNA level, accounts for an important regulatory mechanism in the differentiation of the two cell subsets. In this study, we identify IL-12R expression at the protein level. We have generated an anti-IL-12Rβ2-specific mAb and analyzed IL-12Rβ2 expression on polarized Th cell populations generated in vitro and on T cells derived from patients with Th1- or Th2-mediated inflammatory conditions. Although IL-12Rβ2 was absent in freshly isolated PBMC and in cord blood cells, we were able to detect IL-12Rβ2 expression selectively in differentiated Th1 and T cytotoxic 1, but not Th2 or T cytotoxic 2 cells. In the presence of IL-12, cell surface expression of the IL-12Rβ2 subunit was readily detected on T cells after 24 h, reached the maximum at day 5, and declined thereafter. Most importantly, the anti-IL-12Rβ2 mAb recognizes lung T cells from patients with sarcoidosis, a disease characterized by a typical cell-mediated, Th1-type inflammatory response. In contrast, IL-12Rβ2 was absent in lung T cells from patients with allergic asthma, a disease characterized by a Th2-type inflammatory response. The mAb reported in this study should represent a powerful tool to investigate the role of Th1 and Th2 cells in inflammatory conditions and to monitor therapies aimed at altering the balance of Th cell subsets.

Endoleak (EL) represents the most common complication following endovascular abdominal aortic aneurysm repair (EVAR). Unfortunately, the long-term results of EVAR and its durability have been questioned, and EL are variably associated with a risk of late failure. The aim of this retrospective study was to identify risk factors for this complication of aneurysm-endograft complex in patients who underwent EVAR. A group of 104 consecutive patients (99 men, 5 women; median age, 74 years; range, 50-89 years) were enrolled in the study. Both preoperative and follow-up imaging studies were obtained using helical computed tomography scanning at 1, 6, 12, 24, 36 months after EVAR and blindly reviewed by a surgeon and a radiologist. Twenty-seven (25.9%) patients developed EL during follow-up, of which 10 (37%) were primary (30 days from EVAR), and 17 (63%) were secondary EL. Age and smoking did not affect the EL onset, while a body mass index25 and a history or presence of arterial hypertension represented significant (p0.05) risk factors. Moreover, both greatest diameter and maximum length of the aneurysm were significantly higher (p0.01) in patients who developed EL. No relationship was found with the anatomical features of the aortic neck (i.e. length and diameter), and between the initial size of the aneurysm and the dimension at the time of EL. In conclusion, in our study, being overweight, arterial hypertension and the initial size of the aneurysm represent risk factors for EL development.

Data from 30 consecutive excluded abdominal aortic aneurysms (AAA) have been analysed, to verify whether important morphological changes take place after exclusion, and whether these can be considered as risk factors for functional (leaks, flow alterations) and clinical complications (rupture, obstruction). All AAAs have been initially successfully excluded and patients have been followed up by clinical examinations and ct scan controls post-operatively, at the third and sixth month, then yearly. At a mean follow-up of 17 months, dimension of the proximal neck increased significantly (2 mm in diameter) in five pts and graft was distally dislodged in two. Maximum aneurysm diameter reduced significantly (at east 10% than originally) in half of the case and more than 25% in 10% of cases. Four AAAs presented an initial increase, that reduced only in two. Calculation of length of the AAA was unreliable due to tortuosity. Two secondary type II leaks and one secondary type III leak were observed associated to stable or slightly increased AAA diameter (the latter patient suddenly died probably for miocardial infarction, but a rupture could not be formally excluded). Marked tortuosity of the graft was seen in five patients, all associated with frank shrinkage of the aneurysmal sac. Parietal thrombosis without explanation was observed in five, and in one progressed to obstruction of an iliac branch. Two pts needed anticoagulation. These data indicate that endoluminal aneurysm exclusion can not be considered as a definitive solution, for long-term outcome is unforeseeable in a number of patients.