[en] D-ribose is cytotoxic for quiescent human lymphocytes and severely inhibits their PHA-induced proliferation at concentrations (25-50 mM) at which other simple sugars are ineffective. In order to explain these effects, DNA repair synthesis was evaluated in PHA-stimulated human lymphocytes treated with hydroxyurea and irradiated. D-ribose, in contrast to other reducing sugars, did not induce repair synthesis and therefore did not apparently damage DNA in a direct way, although it markedly inhibited gamma ray-induced repair. Taking into account that lymphocytes must rejoin physiologically-formed DNA strand breaks in order to enter the cell cycle, we suggest that D-ribose exerts its cytotoxic activity by interfering with metabolic pathways critical for the repair of DNA breaks

No abstract available

[en] We have reviewed our experience in diseases involving massive hemoptysis, systematizing the most common causes which include tuberculosis, bronchiectasis and cancer of the lung. Other less frequent causes, such as arteriovenous fistula, Aspergilloma, aneurysm, etc.; are also evaluated, and the most demonstrative images of each produced by the most precise imaging methods for their assessment are presented

[en] Super-hydrophobicity is a well-known and studied phenomenon in the field of surface sciences. In this review we report a novel approach that exploits micro-fabricated super-hydrophobic surfaces for the oriented and self-organized deposition and suspension of DNA filaments and other macromolecules of biological interest. The self-assembled structures obtained with this approach can be used for the characterization of the biological compounds with several methods such as electron microscopy, X-ray diffraction, Raman and SERS spectroscopies. Besides imaging, the described method has been applied in several fields such as the sensing of few molecules in diluted solutions and innovative templating growth. We will focus in particular on the direct imaging of DNA molecules by Transmission Electron Microscopy with the capability to resolve structural details of the double helix down to a resolution of 1.5Å. The review starts with a brief historical note on the discovery of the DNA structure and continues with the results obtained by our group along the last 10 years of activity.

[en] The aim of this study was to define a system for scoring hemophilic arthropathy (HA) based on MR findings, providing for objective evaluation of the degree of joint involvement and evolution after on-demand administration of FVIII substitutional therapy or prophylactic treatment. A total of 133 MR examinations (89 basal and 44 during follow-up) were performed in 25 patients. Patients were divided in two groups depending on the therapy received and the length of time that the disease had been evolving at the start of the study. Group I was composed of 10 patients with secondary prophylaxis and group II was composed by 15 treated on demand. T1-weighted and T2*-weighted images performed on a 0.5-T unit were prospectively evaluated. The joint involvement was established on a scale of 0 (no abnormalities), I (minimal amount of hemosiderin), II (large amount of hemosiderin and isolated cartilaginous erosion), III (cartilage destruction, bone erosions, and subchondral cysts) to IV (large internal joint derangement, secondary osteoarthritis and/or ankylosis). At basal MR examination, patients of group I showed no abnormalities (n=28, 75.6%), grade I (n=3), and grade II (n=6) of HA. Patients of group II corresponded to MR grades III (n=21) and IV (n=11) of HA. The MR follow-up showed improvement in three joints of group I and worsening in 5 joints in group I and 2 joints in group II. Early signs of HA were detected in 10 joints with MR imaging but were underestimated on plain radiographs. Advanced degrees of HA were classified as severe under both imaging techniques. Magnetic resonance is the preferred imaging technique to assess HA. The earliest signs of joint damage, detected by MR, are overlooked by plain radiography. The MR scoring system can be used for evaluating HA. Follow-up MR should be performed to evaluate regression or worsening of the abnormalities, primarily in the case of patients with prophylaxis who usually suffer normal or early joint involvement not detected by other means. (orig.)

[en] The authors compare the results obtained by CT with clinics and conventional radiography in the staging of nasopharyngeal tumors. The accurate evaluation of tumor size, localization, and spread, helps optimize treatment planning and fit radiation boosts on small fields. Twenty-six patients underwent clinical examination, radiography of the skull and neck, lateral stratigraphy of epipharinx, and CT of head and neck. We compared the results obtained in the study of: nasopharyngeal walls, parapharyngeal space, paranasal sinuses, nasal cavity, bone erosion of the base of the skull, and continuous invasion without bone erosions. Our results point to conventional radiology as the examination of choice for the study of upper nasopharyngeal wall, while CT allows a better evaluation of the lateral wall, and is clearly superior in demonstrating parapharyngeal space, contiguous intracranial invasion, and neck nodes involvement

[en] The aim of this retrospective study was to establish whether the distinctive intestinal fold pattern of celiac disease (CD), known by barium studies as jejunoileal fold pattern reversal (JFPR) may be recognized at CT. The number of intestinal folds per 2.5 cm, seen at CT, were counted in the jejunum and in the ileum of 22 adult patients with CD and compared with the folds of 30 consecutive subjects in whom an intestinal disease had been excluded. The results were submitted to statistical analysis by Student's t-test. In the control group the number of folds per 2.5 cm were 4.88 (SD ± 0.78) in the jejunum and 2.84 (± 0.62) in the ileum; in the CD group the number of folds were 2.42 (± 1.61) in the jejunum and 5.11 (± 1.24) in the ileum. There was a statistically significant difference in the number of jejunal and ileal folds between the CD patients and the control group (in both cases p < 0.001). The JFPR was seen in 15 patients with CD (68.2 %) but in none of the controls. Our study shows that JFPR is not a normal finding and can be demonstrated by CT in the majority of patients with CD. (orig.)

[en] Scintimammography shows strong potential in detecting and differentiating breast cancer. This scintigraphic technique, using a standard gamma camera, allows high sensitivity and specificity values (>95%) for detected tumors more than 1 cm size. However, the sensitivity of scintimammography using conventional gamma cameras is considerably less (40-50%) for tumors with smaller size. Recently, the authors demonstrated how the use of a small FOV dedicated gamma camera (Single Photon Emission Mammography, or SPEM camera), with very high intrinsic spatial resolution (1.7 mm FWHM), working with breast moderately compressed and positioned close to the breast tumor (i.e., analogously to X-ray mammography) increased sensitivity up to 80% for tumors sized between 0.5 and 1 cm (T1b). The aim of this paper is to demonstrate how the reduced breast thickness can play a primary role in small cancer detection. Five different methods were taken into account: clinical measurements, comparing tumor SNR values obtained from the same patients in prone scintimammography and in SPEM, comparing SNR values between compressed and uncompressed breast in craniocaudal projection, breast phantom measurements, Monte Carlo simulations and simplified theoretical model. Results confirm that the mechanism for the improvement in visualizing sub-centimeter lesions due to compression is a reduction of lesion-detector distance. As a result of this reduced distance there is a less reabsorption of signal by interposed breast tissue, and improved detector intrinsic spatial resolution

[en] 111 radiographic findings of the chest of 58 patients with chronic renal insufficiency who underwent hemodyalisis are taken into consideration. The results show that the pulmonary congestion with 1 to 1 distribution and the increase of the heart volume are more frequently found. Also interstitial edema, calcification and pleura involvements are present in few cases

[en] Technetium-99m-labelled, non-specific, polyclonal, human immunoglobulin G (^99mTc-hig) has been used to quantify synovial inflammation in rheumatoid arthritis. A comparison was carried out between the scintigraphic results obtained with this tracer, ^99mTc-hexamethyl-propylene amine oxime-labelled white blood cells (^99mTc-WBC) and ^99mTc-albumin nanocolloids (^99mTc-Nc). Twenty patients affected by rheumatoid arthritis and suffering from clinically active synovitis were studied with ^99mTc-hig. The number and sites of the involved joints had been previously assessed on the basis of the presence of pain and/or swelling. A radiological examination had already been carried out on all the joints. Two days after the ^99mTc-hig scan, 10 patients (group 1) underwent ^99mTc-WBC scintigraphy and the other 10 (group 2) underwent a ^99mTc-NC scan. The results show that the results of ^99mTc-hig and ^99mTc-NC scans are in agreement with clinical examinations in the majority of cases. However, a certain number of positive joint scans corresponding to negative clinical examinations was found. The numerical distribution of these results according to the radiological stages seems to show that ^99mTc-hig is more useful than ^99mTc-NC in the initial phases of the disease. The ^99mTc-WBC scan was negative in a consistent percentage of the joints previously assessed as clinically and ^99mTc-hig scan positive. (orig.)