Quasi-continuous distributions of T(1) and T(2) of 1H nuclei were analyzed in vitro at 20MHz on some twenty fresh bone samples of pig femur. Large numbers of data points allowed a detailed investigation. Relaxation data were inverted by UPEN (Uniform PENalty inversion). In all samples the widths of the distributions, covering more than two decades, are not even close to being compatible with single exponential components. Moreover, the T(1) and T(2) distributions show enough character to distinguish the samples. We observe a spatial variation of these characteristics and in particular a second peak centered at 500-600 ms appearing in some proximal femur samples. The quasi-continuous distribution allows one to correlate the water content of the sample with parts of the distributions in specific time ranges. The signal fraction with T(1) values longer than a cutoff time of about 170 ms is in very good agreement with the water content of the samples and is significantly larger in the group of samples cored from proximal femur. Also T(2) distributions differentiate the samples, and the signal fraction with T(2) shorter than about 30 ms is significantly larger in the group of distal femur samples.

Animals↗

PubMedDate not supplied

[Clinical study of dantrolene sodium in the treatment of spastic and dystonic syndromes].

Dantrolene sodium has been given to 45 patients suffering from dyskinetic syndromes: 33 were suffering from spastic syndromes, either secondary to cerebral lesions at birth, or to other cerebral lesions, or to cord lesions; 9 were affected by infantile dystonic syndromes; 1 by dystonia muscolorum deformans and the last 2 patients were suffering from parkinsonism. The best dosage schedule was individual and ranged from 50 mg to 300 mg a day. In this range, the majority of the spastic patients showed reduction of spasticity, unrelated with the site of pathology: a slight one in 12 patients, a moderate one in 9 and a marked one in 2. On the contrary, slight improvement has been noticed in only two of the patients suffering from dystonic syndromes. In no case side effects has been noticed. In all patients who underwent slight or moderate improvement only, we tried to obtain better results on spasticity by growing the dosage schedules; but we have always noticed side effects, that is weakness or drowsiness and, sometimes, urinary uncontinence. Moreover 2 patients showed evidence of transitory metabolic side effects. Therefore our experience shows that dantrolene sodium is an useful drug into the therapy of spasticity, even if often a slight of moderate improvement only is achieved. Slow increase in dosage schedule, repeated laboratory controls and alternate periods of treatment and suspended treatment should be observed.

Adolescent↗

PubMedDate not supplied

SV40 can be reproducibly detected in paraffin-embedded mesothelioma samples.

We studied tissue sections from 18 paraffin embedded mesothelioma specimens diagnosed by the Pathology Department of S. Chiara Hospital of Pisa. Using PCR analysis and Southern blot hybridization we examined the specimens for the DNA regulatory region of the virus. 10/18 (55.5%) of the samples tested contained SV40 DNA regulatory sequences, and of these positive samples, 80% were found to contain Tag sequences by PCR and Southern Blot hybridization. These results confirm that SV40 can be amplified and detected in paraffin embedded mesothelioma samples.

Adult↗

PubMedDate not supplied

Imaging in degenerative disease of the lumbar spine.

Degenerative disease involves all spinal components. Conventional radiology and digital radiology are the procedures of first choice in order to establish the diagnosis. CT and MRI should be considered of second choice, based on precise indications. The physiologic aspects of the spine during aging are differentiated from the degenerative alterations and relative complications specific of arthrosis with modern available imaging procedures.

Aging↗

PubMedDate not supplied

Degenerative disease of the lumbosacral spine: disk herniation and stenosis.

Degeneration of the intervertebral disk complex begins early in life and is a consequence of a variety of environmental factors as well as of normal aging. Degeneration of bone and soft tissue spinal elements is the most common cause of spinal stenosis. The term "degeneration" as commonly applied to the spine covers such a wide variety of clinical, radiological and pathological manifestations that the word is really only a symbol of our ignorance. Computed tomography and myelography have long been used for diagnosing the effects of degenerative diseases' of the lumbar spine. Despite the continuous improvement in magnetic resonance scanning for this purpose, computed tomography can provide excellent screening for disk herniation and spinal stenosis.

Aging↗

PubMedDate not supplied

The lumbar spine: imaging in rheumatic disease.

Seronegative inflammatory spondyloarthropathies include ankylosing spondylitis, psoriatic arthritis, Reiter syndrome, juvenile chronic arthritis and colitic arthritis. These diseases share some characteristics among which the most important is the presence of the histocompatibility antigen HLA B27; moreover the frequent overlapping of the various inflammation patterns have accounted for their classification in a single group. Diagnostic imaging can differentiate among the different forms only if the diagnostic algorithm, based on clinical history and laboratory findings is followed, considering the advantages and limitations of each method. In this respect, it should be kept in mind that the findings relative to the spine and sacroiliac joints allow to establish a definitive diagnosis.

Arthritis↗

PubMedDate not supplied

Imaging of sacroiliac joints.

The early diagnosis of inflammatory and degenerative disease of sacroiliac joints is markedly difficult because the clinical pattern is not dissimilar from that of diseases involving the lumbar spine and sciatic nerve. Furthermore as in inflammations in general, when only structural changes in the synovial membrane and cartilage are involved, the findings of conventional radiology are often nondiagnostic. CT is now considered the gold standard procedure because in spite of its nonnegligible limitations, single lesions in the synovial and ligamentous compartments can be distinctively evidenced. MRI, unlike other procedures, affords the early nonspecific documentation of intrinsic and/or reactive alterations in the subchondral bone, therefore it appears to fill the gap between the onset of symptoms and the imaging visualization of sacroiliitis.

Arthritis↗

PubMedDate not supplied

Combined imaging in spondylodiscitis.

At present, in spite of the advancement in antibiotic therapy no significant decrease in the incidence of spinal infections is observed: most likely, this is correlated to the increased immigration flows, high risk behaviors (drug addiction, alcoholism), immunosuppressive diseases (AIDS, leukemia, lymphoma), interventional procedures (iatrogenic causes). Early diagnosis, at times difficult and often misunderstood, is facilitated by the use of a correct diagnostic algorithm, supported by blood culture, needle aspiration and biopsy. Aim of this report was to evaluate the role of the different imaging procedures, CT and MRI in particular, for prompt correct therapeutic management.

Diagnosis, Differential↗

PubMedDate not supplied

Primary bone tumors and pseudotumors of the lumbosacral spine.

Primary tumors of the spine are relatively infrequent lesions compared with metastatic disease, multiple myeloma, and lymphoma which are the more frequent neoplasms of the spine and usually manifest with multifocal lesions and thus pose little diagnostic dilemma. However, in the presence of a solitary spinal lesion, the more uncommon primary tumors of the spine represent an important group of entities for diagnostic consideration. The most common benign and malignant primary tumors of the spine are enostosis, osteoid osteoma, osteoblastoma, giant cell tumor, aneurysmal bone cyst, osteochondroma, chordoma, chondrosarcoma, Ewing sarcoma, primitive neuroectodermal tumor, and osteosarcoma. The imaging features of these lesions are often characteristic. Radiologists should be aware of the appearance of these unusual tumors in order to provide a complete differential diagnosis.

Diagnosis, Differential↗

PubMedDate not supplied

Osteo-articular, mammographic and thoracic films: clinical evaluation of digital view box versus conventional view box.

PURPOSE: To compare in a clinical setting a conventional view box with a digital view box (Smart Light 2000 Digital Film Viewer System, Smart Light, Israel) in the identification of osteo-articular, mammographic and thoracic lesions. MATERIALS AND METHODS: Six radiologists (two for each imaging procedure), experts in osteo-articular, mammographic and thoracic diseases, independently, compared 600 plain films (100 patient with two projections for each imaging procedure). The radiologists evaluated the films by filling-out a multiple choice questionnaire containing questions concerning the type of pathology seen and the technical quality of the radiography in terms of exposure along with specific questions concerning each of the imaging procedures. RESULTS: We observed a higher sensitivity of the digital view box for lesion identification (p<0.05); furthermore, we analyzed a greater number of radiographs, recovering technically unsuitable films, because of over or under-exposure (high or low optical density). The interreader agreement was also good (> 0.75). The better lesion perception derived from the increase luminance of the digital view box in the evaluation of higher film densities, such as in overexposed films. DISCUSSION. The technical characteristics of the digital view box reduce or eliminate negative factors that reduce perceptional performance, and often permit the recovery of films that would have otherwise been considered technically unreadable.

Arthrography↗

PubMedDate not supplied

[SV40: a possible co-carcinogen of asbestos in the pathogenesis of mesothelioma?].

BACKGROUND: The etiopathogenic role of asbestos in causing malignant mesothelioma of the pleura is clearly supported by an impressive amount of data. Despite the frequent association with previous exposure to asbestos, only a relatively small fraction of those exposed develop malignant mesothelioma. The long latency period between initial exposure and onset of the tumor suggests that human mesothelioma, like many other tumors, has a multi-stage evolution with the occurrence of many mutating events involving various tumorigenic agents, probably in part initiating and in part promoting development. Recently this has raised great interest in the scientific world, in an attempt to identify possible factors which together with asbestos may have a role in developing this rare malignant tumor. Ionizing radiations and genetic susceptibility have occasionally been identified as the culprits. A virus called SV40 has been gaining increasing scientific credibility since the mid 1990's as a potential co-carcinogen of asbestos. OBJECTIVES: The aim of this article was to examine the supposed interaction between asbestos and SV40 in the pathogenesis of mesothelioma and the way this simian virus has become a human virus. METHODS: All biomolecular and epidemiological data available from medical literature along with the results of the experiments performed during the last 7 years in our department laboratories were reviewed and compared. RESULTS: The first two pieces of experimental evidence of the presence of SV40-like DNA sequences in mesothelioma samples were obtained in 1994 in the United States, and one year later in our laboratories. After these two studies many research groups started carrying out similar experiments, obtaining comparable results in most cases. Moreover, beyond the mere detection of viral DNA sequences large amount of biomolecular data has recently been added in favour of its role in the pathogenesis of mesothelioma. Epidemiological studies published to date were unable to provide similar unanimous results. Data regarding the source of human infection are still debatable, even if the inadvertent administration of contaminated poliovaccines to millions of people in Europe and the United States between 1955 and 1963 remains one of the most reasonable hypotheses. CONCLUSIONS: On the basis of all the biomolecular data reviewed and partially on the basis of epidemiological studies, SV40 seems to be the best candidate as a cofactor with asbestos in the development of human mesothelioma.

Animals↗

PubMedDate not supplied

[Quantitative bone ultrasonography: state of the art and perspectives].

Quantitative Ultrasound (QUS) is a relatively new method of bone assessment that measures the velocity of sound and the broadband ultrasound attenuation at different skeletal sites: heel and phalanges. This is a mobile, inexpensive, easy to perform and radiation-free technique, capable of assessing not only bone density, commonly measured by means of Single Energy X-ray Absorptiometry, SXA, Dual Energy X-ray Absorptiometry, DXA and Quantitative Computed Tomography, QCT, but also its elasticity and structure. QUS has been validated for diagnosis of osteoporosis and prevention of hip fractures. Very recently, QUS was also been applied to the study of uremic osteodistrophy, of female premenopausal osteoporosis, male osteoporosis and in paediatric population. Moreover, many studies in the dialysis population has also shown the effectiveness of QUS at the phalanges site in evaluating bone turn-over and bone osteopenia. QUS may be an useful tool for the nephrologist in the day by day monitoring of uremic osteodistrophy and secondary hyperparathyroidism.

Bone Density↗