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Background: In light of recent developments in nanotechnologies, interest is growing to better comprehend the interaction of nanoparticles with body tissues, in particular within the cardiovascular system. Attention has recently focused on the link between environmental pollution and cardiovascular diseases. Nanoparticles <50 nm in size are known to pass the alveolar-pulmonary barrier, enter into bloodstream and induce inflammation, but the direct pathogenic mechanisms still need to be evaluated. We thus focused our attention on titanium dioxide (TiO₂) nanoparticles, the most diffuse nanomaterial in polluted environments and one generally considered inert for the human body., Methods: We conducted functional studies on isolated adult rat cardiomyocytes exposed acutely in vitro to TiO₂ and on healthy rats administered a single dose of 2 mg/Kg TiO₂ NPs via the trachea. Transmission electron microscopy was used to verify the actual presence of TiO₂ nanoparticles within cardiac tissue, toxicological assays were used to assess lipid peroxidation and DNA tissue damage, and an in silico method was used to model the effect on action potential., Results: Ventricular myocytes exposed in vitro to TiO₂ had significantly reduced action potential duration, impairment of sarcomere shortening and decreased stability of resting membrane potential. In vivo, a single intra-tracheal administration of saline solution containing TiO₂ nanoparticles increased cardiac conduction velocity and tissue excitability, resulting in an enhanced propensity for inducible arrhythmias. Computational modeling of ventricular action potential indicated that a membrane leakage could account for the nanoparticle-induced effects measured on real cardiomyocytes., Conclusions: Acute exposure to TiO₂ nanoparticles acutely alters cardiac excitability and increases the likelihood of arrhythmic events.

Unlabelled: Self-cleaning photocatalytic coatings for biocalcarenite stones, based on TiO2 nanoparticles obtained by sol-gel processes at different pH values and also adding gold particles, have been investigated. The selected test material is a biocalcarenite named "pietra di Lecce" (Lecce stone), outcropping in Southern Italy. Scanning electron microscopy with energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, and Raman investigations were carried out to characterize the TiO2 nanoparticles and coatings. Nanocrystalline anatase and, to a lesser extent, brookite phases are obtained. Photocatalytic activity of the TiO2 sols and of the coatings on "pietra di Lecce" was assessed under ultraviolet irradiation, monitoring methyl orange (MeO) dye degradation as a function of time. To evaluate the harmlessness of the treatment, colorimetric tests and water absorption by capillarity were performed. The results show good photodegradation rates for titania nanosols, particularly when putting in Au particles, whereas a satisfactory chromatic compatibility between the sol and the surface of the calcarenite is found only without Au addition., Highlights: Sols of nanocrystalline titania at different pH values and with Au particles were prepared and characterized. Satisfactory photodegradation of MeO by the sols in solution and on calcarenite-coated surfaces is obtained. The addition of Au particles improves the photodegradation activity but gives poor chromatic results on "pietra di Lecce."

During the last decades, Raman spectroscopy has grown to an established analytical technique in archaeometry, art analysis and conservation science. Mobile Raman instruments were designed to be used for in situ characterisation and identification of inorganic and organic materials in art and archaeometry. This research paper aims to point out several aspects that need to be considered when selecting a mobile Raman spectrometer for in situ archaeometrical studies. We describe an approach to evaluate these parameters and apply this to a dual laser portable Raman spectrometer. Twofold characterisation of mobile Raman instrumentation for art analysis: (i) investigation of spectroscopic characteristics such as (amongst others) spectral resolution, spectral window, signal to noise ratio and limit of detection; (ii) evaluation of specific properties that are useful for mobile studies in archaeometry. These include options for easy positioning and focussing, the ability to reduce laser power on the surface of the art object and the working distance between the probehead and the artefact. Finally, the research was completed with field tests by studying the pigments of a mediaeval wall painting., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Three bronze samples created by CNR-ISMN (National Research Council-Institute of Nanostructured Materials) to be similar to Punic and Roman coins found in Tharros (OR, Sardinia, Italy) were studied to identify the corrosion products on their surfaces and to evaluate the reliability of the reproduction process. Micro-Raman spectroscopy was chosen to investigate the corroded surfaces because it is a non-destructive technique, it has high spatial resolution, and it gives the opportunity to discriminate between polymorphs and to correlate colour and chemical composition. A significant amount of green copper hydroxychlorides (Cu(2)(OH)(3)Cl) was detected on all the coins. Their discrimination by Raman spectroscopy was challenging because the literature on the topic is currently confusing. Thus, it was necessary to determine the characteristic peaks of atacamite, clinoatacamite, and the recently discovered anatacamite by acquiring Raman spectra of comparable natural mineral samples. Clinoatacamite, with different degrees of order in its structure, was the major component identified on the three coins. The most widespread corrosion product, besides hydroxychlorides, was the red copper oxide cuprite (Cu(2)O). Other corrosion products of the elements of the alloy (laurionite, plumbonacrite, zinc carbonate) and those resulting from burial in the soil (anatase, calcite, hematite) were also found. This study shows that identification of corrosion products, including discrimination of copper hydroxychlorides, could be accomplished by micro-Raman on valuable objects, for example archaeological findings or works of art, avoiding any damage because of extraction of samples or the use of a destructive analytical technique.

Being nondestructive and requiring short measurement times, a low amount of material, and no sample preparation, Raman spectroscopy is used for routine investigation in the study of gemstone inclusions and treatments and for the characterization of mounted gems. In this work, a review of the use of laboratory Raman and micro-Raman spectrometers and of portable Raman systems in the gemology field is given, focusing on gem identification and on the evaluation of the composition, provenance, and genesis of gems. Many examples are shown of the use of Raman spectroscopy as a tool for the identification of imitations, synthetic gems, and enhancement treatments in natural gemstones. Some recent developments are described, with particular attention being given to the semiprecious stone jade and to two important organic materials used in jewelry, i.e., pearls and corals.

Raman spectroscopy represents a new way to obtain detailed comprehensive information on heavy-mineral assemblages. In this work are presented several examples from major Alpine (Po River) and Himalayan (Ganga and Brahmaputra Rivers) fluvio-deltaic sands. Our attention was focused on the chemical properties of garnet, which is a widespread mineral in orogenic sediments, easy to be identified, and relatively stable during both equatorial weathering and intrastratal dissolution. Garnet grains were studied in different samples representative of various depositional environments (fluvial bar, fluvial levee, shoreface, beach berm, eolian dune), in order to investigate specifically the hydraulic behaviour of grains with different density in different hydrodynamic conditions. Raman spectra and semi-quantitative analysis of Raman shifts allowed us to rapidly determine the distribution of garnet types in each sample in order to obtain chemical composition, to calculate the density of each garnet, and finally to infer their respective provenance. This manuscript presents one possible application of the "MIRAGEM" method described by Bersani et al. in this volume. References, data sets and details on the analytical routine are widely explained in the above mentioned work.

Green colored samples on wall paintings and green powder from a pigment pot found in Pompeii area are investigated by micro-Raman, FT-IR and, for one sample, SEM-EDX. To obtain the green color, green earths and malachite were used, together with mixture of Egyptian blue and yellow ochre. The mineralogical identification of the green earths has been attempted through the comparison of the vibrational features, discriminating between celadonite and glauconite spectra. Traces of a modern synthetic pigment containing copper phthalocyanine were found in a fresco fragment.

Fluid inclusions in the quartz crystals present in gold-rich veins from central Honduras have been studied by means of micro-thermometry and micro-Raman spectroscopy in order to provide information on the physico-chemical conditions and chemical composition of the mineralizing fluids. The use of a confocal micro-Raman apparatus allowed to obtain information on the fluid composition, in particular on the gas phase, minimizing the contributions of the host matrix to the Raman signal. The samples studied were collected from an area (Lepaguare mining district, Northern-Central Honduras) rich in ore deposits due to the Cenozoic magmatic activity, where the gold and sulphide mineralization is connected with a system of quartz veins (few decimetres thick) occurring in low-grade metamorphic rocks and produced by hydrothermal fluids. The quartz crystals present in the gold-rich veins often contain fluid inclusions. Four types of fluid inclusions have been observed, but their assemblage in the same clusters and fracture systems, as well as their comparable salinity and homogenization data, suggest that they have the same origin. Micro-thermometry and Raman spectroscopy provide a composition of the mineralizing fluids attributable to the system H(2)O-NaCl-KCl-CO(2)-CH(4), with temperature and pressure intervals of 210-413 degrees C and 1050-3850 bar, respectively. These data agree with an epigenetic origin of the gold deposit (depth < 6 km) related to granitoid or granodiorite intrusions associated to orogenic environments.

Two holy water fonts (dated at the beginning of the XVII century) in the Santa Maria della Steccata Church in Parma (Italy) have recently been restored. Before the intervention, a detailed investigation on their degradation products was carried out to understand the mechanisms of alteration of the materials and to suggest appropriate restoration procedures. The analyses were performed by means of powder X-ray diffraction (XRD), micro-Fourier transform infrared (FTIR) and micro-Raman spectroscopies. Calcite, iron oxides, silicates and sodium chloride (from salted holy water) were found in the red coloured calcarenite. On and under the lead coverings, different lead oxides (mainly massicot), other lead salts (lead basic carbonate, cerussite, plumbonacrite Pb10O(OH)6(CO3)6 and lead-chlorine compounds as laurionite PbOHCl and phosgenite Pb2CO3Cl2) were identified by Raman spectroscopy and XRD. Haematite alpha-Fe2O3, goethite alpha-FeO(OH) and lepidocrocite gamma-FeO(OH) were found on and around the iron hinges. Lead compounds and sodium chloride, through crystallization and solubilization cycles, were responsible for the stone's degradation, whereas the iron corrosion materials on the hinges produced mechanical stress and cracks in the stone. Various suggestions have been given on how to restore these fonts and to remove the causes of damage.

Purpose: Thoracic outlet syndrome includes arterial, venous or neurological symptoms. Frequently difficult to diagnose clinically, confirmatory imaging studies are usually required. The purpose of this study is to review the diagnostic work-up during management of patients with thoracic outlet syndrome and demonstrate the value of angiography in the sitting position., Materials and Methods: Retrospective study of 81 surgical procedures for thoracic outlet syndrome, between 1997 and 2005, in 56 patients aged 17-57 years. Surgery was bilateral in 26 cases, with bilateral surgery in a single setting for 1 patient. All patients presented clinical symptoms confirmed on US, angiography, venogram or EMG. Angiography, from a transfemoral approach, was initially performed in the supine position, without and with dynamic maneuver, and in the sitting position with dynamic maneuver when needed., Results: In 48 patients, supine rest angiography showed stenosis in 6% of cases and supine dynamic angiography showed stenosis in 81% of cases, with severe stenosis in only 35% of cases (stenosis>80% or arterial occlusion). Angiography in the sitting position was performed in 33 patients, showing worsening of stenosis in 91% of cases, with severe stenosis in 87%., Conclusion: Angiography in the sitting position with dynamic maneuver improves the sensitivity for detection of thoraci coutlet syndrome. This procedure may be considered in addition to other imaging modalities routinely used including Doppler US, CT and MRI.

Background: Stroke is the most common cause of permanent disability in Europe and is a major public health problem. A recent significant therapeutic advance is the administration of recombinant tissue plasminogen activator (rtPA) for cerebral infarcts within three hours of symptom onset. French guidelines limit its use to patients in specialized stroke units. There is only one stroke unit in the region of Aquitaine, in Bordeaux, 200 km from Pau and too far to transfer patients within the necessary time. With the collaboration of our colleagues in Bordeaux we decided to assess whether stroke thrombolysis could be feasibly and safely administered in our district general hospital., Design: From September 2004 through August 2005, eligible patients received rtPA treatment in the emergency department. The National Institutes of Health Stroke Scale (NIHSS) was administered at admission, immediately after treatment, and 24 hours later. In January 2006, a prospective follow-up assessed the NIHSS, Modified Rankin Scale (MRS) and Barthel Index Score (BIS) for all subjects still alive and collected data about those who had died., Results: In all, 553 patients were admitted for stroke: 306 had cerebral infarcts and 25 (8.1%) were treated by intravenous thrombolysis. The mean age of the patients who received thrombolysis was 67 years (range: 33-80), and the sex ratio was 4/1 (20 men and 5 women). Mean delay from symptom onset to treatment was 150 min (range 105-180). The median NIHSS score was 13 (range 8-22) at admission, 10 (range 0-22) after treatment, and 7 the next day (range 0-22). Two patients (8%) died during the acute phase. On January 2006, after a median follow-up of 11.6 months (range: 6-16), 18 (72%) patients were still alive: 13 (52%) with good outcomes (MRS, 0-1) and 3 severely disabled and institutionalized (BIS, 0-50)., Conclusion: Our results show that thrombolysis is possible in Pau. The population in our catchment area has a good proportion of stroke patients eligible for thrombolytic treatment. Outcomes and mortality rate are consistent with experience elsewhere. The creation of a stroke unit should help improve prognosis while complying with management guidelines.

Polarization holographic gratings in sp configuration are written at 488 nm in photorefractive organic-inorganic films based on SiO2. The films, prepared by a solgel technique, contain Disperse Red 1, carbazole units, and 2,4,7-trinitro-9-fluorenone. The gratings are characterized by their diffraction efficiency for a 632.8-nm probe. The polarization gratings act as a half-wave plate, and the diffraction efficiency is independent of the polarization direction of the probe.

Micro-Raman spectroscopy, combined with gas chromatography and ultra-violet fluorescence photography, was used to study some wall paintings in the S. Giovanni Evangelista Abbey in Parma, Italy. The restoration of some painted chapels enabled a comparison between two painters of the 16th century: Parmigianino (Girolamo Francesco Maria Mazzola, 1503-1540) and Michelangelo Anselmi (1492?-1556?). Micro-Raman spectroscopy determined the palette used by the artists, leading to the identification of different white, yellow, red, brown, green, blue and black pigments. Some pigments are evidence of later restorations. Gas chromatography combined with mass spectroscopy revealed the presence of organic binding media and enabled to distinguish between fresco and secco paintings.

Objective: This study evaluated the diagnostic accuracy of high-spatial-resolution sonography in the diagnosis of occult fractures of the waist of the scaphoid., Subjects and Methods: Sonography of the scaphoid bone with a 12-MHz transducer was performed in 54 patients with clinically suspected scaphoid fracture and normal findings on initial radiographs, including specific scaphoid images. Three levels of clinical suspicion were considered: high (20%), moderate (30%), and low (50%). Attention was paid to the continuity of the scaphoid cortex and to the surrounding soft tissues (i.e., hemarthrosis or hematoma). Data from early sonograms were then compared with the results of radiography repeated 10-14 days after the initial trauma. In cases of persistent suspicion despite normal findings on follow-up radiographs, the presence of fracture was evaluated on CT (four patients), MR imaging (one patient), or bone scanning (one patient)., Results: Follow-up examinations proved fracture of the scaphoid waist in five patients. In all patients, diagnosis of fracture was suspected on initial sonograms showing cortical disruption associated with soft-tissue abnormalities. There was one false-positive finding and no false-negative results. Using cortical disruption as a diagnostic criterion, we found the sensitivity, specificity, and accuracy of high-resolution sonography for the depiction of scaphoid fracture to be 100%, 98%, and 98%, respectively. Using soft-tissue abnormalities alone as a criterion, we found the sensitivity, specificity, and accuracy of high-resolution sonography to be 100%, 65%, and 68%, respectively. The overall prevalence of occult fracture was 9%, ranging from 3.7% for low suspicion to 27% for high suspicion of fracture., Conclusion: High-resolution sonography is a reliable and accurate method of evaluating occult fractures of the scaphoid waist. Cortical disruption is the diagnostic key. Soft-tissue abnormalities alone lack specificity.

Intramedullary metastases from a non neurogenic cancer are relatively rare, representing approximately 1-2,1% of metastatic sites according to published autopsy reports. Their association with syrinx is extremely rare. Four cases have been described in the last 30 years. We report the case of a 60 year old female with past medical history of Peutz-Jeghers disease, who presented with clinical signs suggestive of medullary lesions of the cervical spine. MR imaging showed tumoral lesions at different levels associated with syrinx. Surgical biopsy confirmed the intramedullary lesions which, by pathology, were found to be of metastatic origin.

We report one case of traumatic rupture of the inferior vena cava. CT was performed during the acute phase and showed retroperitoneal hematoma near the inferior vena cava with extravasation of contrast agent. After stabilization angiography showed pseudo-aneurysmal picture of inferior vena cava.

The authors recall the anatomy of the deep neck spaces and report the case of a 3-year-old girl with a parapharyngeal abscess followed by a pseudo-aneurism of the carotide artery. Ultrasonography, CT scan and angiography findings are described. This case puts in mind of the seriousness of neck abscesses. Each specific anatomical location must be definite for a better therapeutic approach on account of hemorrhagic risks of parapharyngeal abscesses.

The authors report a case of a gastric involvement by a multiple myeloma, suspected on ultrasonography although the gastric endoscopy was normal. The barium examination and the CT scan agreed with the ultrasound hypothesis confirmed by histology.

The sonographic pattern of an intussusception in a 21 months old child is reported. The value and the meaning of this pattern is discussed according clinical and anatomical presentation of intussusception.

The authors describe the different imaging techniques and their interest. They discuss their etiology. The association with stenosis of the coeliac axis incites to think at a hemodynamic theory.

Carcinoid tumors of the rectum are rare and their radiologic visualization is exceptional. In the series we report about an incidental finding during double contrast enema which takes the form of an expanding tumor developing inside the intestinal lumen and showing no signs of malignity. Standard investigation in the follow up of rectal carcinoid tumors showed no hepatic mestastisis, no other foci in the digestive tract and no biologic anomalies. The patient did not complain of carcinoid syndrome. Double contrast enema is the only process enabling the discovery of rectal masses so small with non negligible frequency (2% of our explorations). Whatever the radiologic aspect and localization, fibroscopic and histologic examinations are necessary in order to make an accurate diagnosis of their nature.

The authors describe two personnel observations of ileal carcinoid tumors, demonstrated by double contrast small bowel examination. Confirmation came from operation and histology. Small bowel examination can demonstrate limited carcinoid tumors giving no angiographic traduction.

The authors study a case of nodular lymphoid hyperplasia, extending from the duodenal bulb to the rectum, associated to an agammaglobulinemia; they observe the variations of the roentgenology appearance and the distribution of the elementary pictures; they discuss the meaning of the disease, the association or the evolution to a lymphoid carcinoma.

Fifty seven patients (51 women and 6 men) undergoing cholecystectomy had ultra-sound evaluation on the 3rd, 5th, 7th and 9th post-operative days. In all the cases, the right upper quadrant has been observed correctly with a phased array 3.5 MHg transducer. Eleven of the fifty seven patients (19%) were found to have fluid collection in the gallbladder fossa. The collection has a rounded or an oval configuration, in the proportion of 11 and 55 mm, surrounded by an echogenic area. These fluid collections were of no clinical and biological significance and disappeared in 2 or 4 days time. The authors discuss the relationship between the presence of fluid and the use of drains or different surgical techniques.

Osteolysis of the distal clavicular shaft is an uncommon sequel to trauma. The clinical and radiological aspects are described. The pathogenesis and the early manifestations of osteolysis are discussed.