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M Fadda

Publications and source records attributed to M Fadda.

36 records · Page 2Linked to original sources
PubMed1991

[Morphologic scanning electron microscopic study of quantitative variations in the endosseous diaphyseal surface in normal and osteoporotic rats].

An ultrastructure study (S.E.M.) was performed on adult albino rats of the age, sex, and weight in order to assess the qualitative and quantitative variations in the endosteal diaphyseal surface of limbs relieved of mechanical stresses by means of prolonged cast immobilization. The final results confirmed the primary role played by osteoclasts and vascular bone channels, the latter of which open into the diaphysis, during resorption of compact diaphyseal bone, which occurs to the detriment of the bone surfaces in deposition and at rest.

Animals↗
PubMed1991

[The mineralization process in osteochondroma. A scanning electron microscopic study].

Thirty patients affected by osteochondroma were divided in two groups: 15 patients were in the age of development, and 15 patients had ended their development. The patients' age ranged from 4 to 42 years; 18 of them were males. The mineralization process (M.P.) of the osteochondral tissue was studied following hypochlorite treatment of the specimens. M.P. was particularly evident in patients during development and was characterized by round calcific nodules (calcospherites) which were linked to crossed collagen fibers. M.P. was morphologically similar to what is usually observed in normal and pathological specimens. Except in two cases, at the end of development the intertrabecular spaces were free of calcific material. In those two cases we observed a resumption of M.P. Mineralization was of calcospheritic type and started from islands of metaplastic cartilage. It was interpreted as a sign of possible transformation to peripheral chondrosarcoma. In a third case, osteoclastic activity caused deep, wide subperiosteal and trabecular erosion resulting in osteocartilaginous neoplastic tissue involution.

Adolescent↗
PubMed1990

[A clinical contribution to the conservative surgical therapy of giant follicular cysts of the mandible].

Three clinical cases of mandibular giant follicular cyst were described. Personal experience with an initial conservative approach is described and some interesting conclusions about the short time of bone new generation of maxillary are presented. As soon as possible, the extraction of impacted tooth will be made without the risk of mandibular fracture or vascular-nervous lesions.

Adult↗
PubMed1990

Morphological aspects of the synovial membrane and the femoral epiphyseal nucleus in anemia induced experimentally (note 1).

The authors describe the macroscopic and ultra-structural changes in the synovial membrane and the growth nucleus consequent to anemia induced experimentally. In the anatomical region studied an early and a late response to the transitory anoxia is observed. The former is represented by the accentuation of the macrophagic activity of the A synoviocytes and by pictures of trabecular fragmentation. The latter is represented by hyperplasia of the synovial membrane, a reduction in the thickness of the joint cartilage, and by early and patchy calcification of the epiphyseal disc.

Anemia↗
PubMed1990

[Osteoid osteoma. A scanning electron microscopic study].

The mineralization process of the osteoid osteoma, after removal of the organic matrix from the specimens by treatment with 6% sodium hypochlorite, has been studied by SEM. The process was characterized by calcified nodules or calcospherites, variable in size from 0,1 to 2 microns, embedded among randomly oriented collagen bundles, which delimited trabeculae of sponge primary bone. Numerous osteocytic lacunae, in various degrees of development, in the mineralizing front were present. The ultrastructural feature of the mineralization in osteoid osteoma reflected a pattern of nodular and collagenous calcification, essentially similar to primary calcification, characteristic of rapidly developing woven bone.

Adolescent↗
PubMed1990

[Osteosis due to primary hyperparathyroidism. The SEM ultrastructural features of the periosteal and endosteal surfaces].

The study of four cases of osteosis caused by primary hyperparathyroidism, tree female and one male, which have undergone surgery for pathological fractures in met-epiphysis bone, allows to analyze with the help of scanning electron microscope modifications occurring in periosteal and endosteal bone matrix. The periosteal surface appears abundantly furrowed by large and deep canals, irregularly joined together. Areas of resorption, these at rest and these of osteodeposition are distributed in changeable but regular way. The bone turnover of endosteal side is particularly accentuated. This surface contains the bone trabeculae residuals and is widely marked by deep Howship's lacunae, which show intense osteoclastic activity. It seem that osteocytes cells participate actively in the process of osteolysis, widening the lacunae and small canals which appear to be surrounded by calcospherites arranged in irregular way. Osteogenetic activity, with large areas of deposition, is very intense, as a defence attempt against osteolytic resorption process.

Adult↗
PubMed1990

[The ultrastructural aspects of the synovial intima and subintima in arthrosis].

Synovial membrane removed surgically from patients during developing degenerative joint disease were studied under a scanning and transmission microscope. The results show that the synovial membrane is folding into villi of average dimensions (microvilli and macrovilli) which project into articular cavity. In regard to the villi, the morphology is locally changeable, with the atrophic-sclerotic areas alternated with hyperplastic areas, but topographically well defined. In the last ones, structural modifications of the intima layer, are characterized by hypertrophy of B synoviocytes, which are constituent and predominant cells in comparison with other cell-types. In the subintima around ectatic vessels, the linfomonocitary inflammatory infiltrations may be found. These alterations are the results of active biological process and because of this synovial membrane is of big importance in developing of osteoarthritis.

Aged↗
PubMed1990

Ultrastructural characteristics of the human synoviocytes.

The purpose of this study was to identify, by the scanning electron microscopy, the behaviour of the different cell types in the normal human synovial intima, in order to obtain information useful for interpreting pathological changes in the synovium. Our observations revealed that, in numerous areas of the synovial membrane (adipose or fibrous type), the synoviocytes were dispersed and the intercellular matrix, covered only by the cytoplasmic processes of cells deeply located, was in direct contact with the joint cavity. In the areolar type of the synovium the synoviocytes were more numerous; they tended to concentrate to give the appearance of a continuous tissue; but between the cells very large intercellular spaces were usually present. In this latter membrane type we identified the two main cellular types of the synoviocytes: A and B. B-synoviocytes were the predominant cell type of the synovium. These cells were characterized by long cytoplasmic processes, perpendicularly directed towards the joint cavity. Both the cellular body and the cytoplasmic processes were covered by small blebs and vesicles of various size. The A-synoviocytes were a small minority, rarely dispersed between the B-synoviocytes. They were characterized by numerous membrane infoldings which delimited intracellular canaliculi of various depth. Our ultrastructural observations demonstrated that, in normal conditions, the B-synoviocyte must be considered as a constitutive element which characterized the synovial intima, responsible for the specific structure of the interstitial tissue and for the regulation of the composition of the synovial fluid.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1988

A comparison between computerized tomography and myelography in radicular lumbar syndromes.

The clinical, tomographic and myelographic findings in 40 patients with radicular lumbar syndromes are analysed and discussed. The study shows that indications for surgical treatment must take into account errors in determining the level of the syndrome based on clinical examination (25%), false negatives (10%), and false positives (15%) resulting from CT scan and, finally, false negatives resulting from myelography (10%). It is emphasized that at present there is no real evidence to support preference for one or other of these instrumental tests. Only the clinical examination is capable of evaluating each case individually and thus providing the most reliable indications on which to base both diagnosis and treatment.

Adult↗
PubMed1985

Clinical and electrophysiological investigation of the results of operation for lumbar disc hernia. Preliminary results.

The long-term results of operations to remove disc hernias were assessed clinically and electrophysiologically in two groups of patients treated by different surgical techniques. The electrophysiological parameters determined were the motor conduction speed of the sciatic nerve, the H reflex, the minimum latency of the F wave and quantitative analysis of the EMG by the Willison method. The preliminary results reported in the present paper are related to two comparable samples of patients who underwent hemilaminoarthrectomy or hemilaminectomy for disc hernia at L5-S1. They show that the incidence of after effects was lower in the patients treated by simple hemilaminectomy.

Adult↗
PubMedDate not supplied

Outcome of cancer patients receiving home parenteral nutrition. Italian Society of Parenteral and Enteral Nutrition (S.I.N.P.E.).

BACKGROUND: Indication for home parenteral nutrition (HPN) in cancer patients is controversial because intestinal failure and malnutrition are often only two of the many problems found in such patients that may deserve priority of treatment. METHODS: This was a retrospective study of 75 cancer patients from nine institutions included in the Italian HPN Registry. The patients had a mean weight loss of 12.5%, serum albumin of 3.1 g/dL, lymphocyte count of 1150/mm3, and serum total iron-binding capacity of 190 micrograms/dL. The main indication for HPN was intestinal obstruction (66%); 72% of the patients had metastatic disease. A series of demographic, oncologic, and nutritional characteristics were analyzed in an attempt to predict a possible benefit of HPN. RESULTS: A total of 9897 days of HPN were delivered to 75 cancer patients, for a median of 4 months (range 1 to 15 months) per patient. Sixty-nine patients died while receiving HPN, five had a remission of their intestinal failure, and one chose to stop the treatment. Complications related to parenteral nutrition were as follows: 19 cases of sepsis, 6 catheter occlusions, 4 catheter dislocations, and 2 metabolic imbalances. HPN preserved nutritional status and slightly improved weight, lymphocyte count, serum albumin, and Karnofsky performance status in patients who survived > 3 months. Quality of life during HPN was judged by the clinicians to have improved in only 9% of those who survived < 3 months, but in 68% of the patients who survived for > 3 months. Karnofsky performance status > 50 at the start of HPN was correlated with longer survival (p = .02). CONCLUSIONS: Our study demonstrated a positive effect of HPN on nutritional status and quality of life in patients who survived > 3 months and suggests that HPN should be avoided when Karnofsky performance status is < 50.

Adult↗
PubMedDate not supplied

Improving accuracy of bone resections using robotics tool holder and a high speed milling cutting tool.

The use of non-cemented prosthetic components in implant surgery is demanding a high quality of bone beds in order to allow for a good level of osseointegration. Two parameters are significant in the evaluation of the quality of the host bone: roughness, which reports on the presence of gaps and peeks, and flatness, which reports on the total percentage of bone which lies in a given interval from the prosthesis. Robot assisted cutting of 32 pig femours and tibiae was performed using various techniques and options. This paper demonstrates roughness and flatness can be taken of the order of the limits necessary for osseointegration, by using a milling cutting tool mounted on a strong support, in this case a robot arm, improving on the results obtained by similar studies referred to hand sawed bones by 10 times.

Analysis of Variance↗
PubMedDate not supplied

[3-dimensional characterization of the synoviocytes of the human synovial intima].

The intimal synovial surface in normal conditions, using a scanning electron microscope, has been studied. The three synovial membrane types are clearly recognizable: fibrous (Fig. 8), adipose (Figs. 9 and 10) and areolar (Figs. 1 and 2); but only in the areolar type, the characterization of the main two cellular types: synoviocytes B and A, is possible. Synoviocyte B represents the constitutive element which characterizes the synovial intima; it has a cellular body of irregular shape and long cytoplasmic processes directed towards the joint cavity (Figs. 3, 4 and 5). The cellular body and the cytoplasmic processes are covered by small blebs (Fig. 6). and similar vesicles, probably of the same cellular origin, are scattered throughout the extracellular matrix. These cells are likely responsible for the specific structure of the interstitial tissue adapted to the exchanges and to the regulation of the composition of the synovial fluid (Okada et. al. 1981; Linck and Porte, 1978, 1981). Synoviocyte A is a small minority; it has many long and irregular membrane infoldings which define a complicated system of intracellular canaliculi of various depth (Fig. 7). The ultrastructural characteristics of their surface and the peculiarity of their organelle apparatus, described by other AA. (Fell et. al., 1976), demonstrate that these elements carry out a macrophagic function. The clear majority of the synoviocytes B in the intimal surface suggests that in normal conditions, the synthesizing processes prevail over the phagocytosis ones.

Adult↗
PubMedDate not supplied

[The role of early protein restriction in patients with initial renal insufficiency].

The effect of early protein restriction (0.6 g:kg/p.i./die) in patients suffering from initial kidney failure for a period of two years has been studied. The hypoprotein diet proved effective in slowing development of kidney damage in so far as a stabilization was observed in renal function parameters during the hypoprotein diet period compared to the non-diet period.

Adult↗
PubMedDate not supplied

Human articular cartilage during osteoarthrosis: a study under the scanning electron microscope.

The present study has been carried out with the aim of contributing, by means of the Scanning Electron Microscope (SEM), to the understanding of morphological changes in human articular cartilage during osteoarthrosis. Fragments from the femoral head of 10 patients subjected to total hip joint prosthesis were cryofractured and then studied by SEM after treatment with current procedures. The images obtained were considered observing the division of cartilage into superficial, medium and deep layers. The superficial layer is the one which suffers most seriously during osteoarthrosis, but collagen alterations, as fibrillation, involve all the layers together. Moreover, the observation of deformed cellular lacunae in the deep layer suggests that a precocious functional collapse involves the whole thickness of the cartilage, probably due to a metabolic suffering.

Aged↗