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M Tassinari

Publications and source records attributed to M Tassinari.

16 recordsLinked to original sources
PubMed2006

EFNS guidelines on the diagnosis and management of orthostatic hypotension.

Orthostatic (postural) hypotension (OH) is a common, yet under diagnosed disorder. It may contribute to disability and even death. It can be the initial sign, and lead to incapacitating symptoms in primary and secondary autonomic disorders. These range from visual disturbances and dizziness to loss of consciousness (syncope) after postural change. Evidence based guidelines for the diagnostic workup and the therapeutic management (non-pharmacological and pharmacological) are provided based on the EFNS guidance regulations. The final literature research was performed in March 2005. For diagnosis of OH, a structured history taking and measurement of blood pressure (BP) and heart rate in supine and upright position are necessary. OH is defined as fall in systolic BP below 20 mmHg and diastolic BP below 10 mmHg of baseline within 3 min in upright position. Passive head-up tilt testing is recommended if the active standing test is negative, especially if the history is suggestive of OH, or in patients with motor impairment. The management initially consists of education, advice and training on various factors that influence blood pressure. Increased water and salt ingestion effectively improves OH. Physical measures include leg crossing, squatting, elastic abdominal binders and stockings, and careful exercise. Fludrocortisone is a valuable starter drug. Second line drugs include sympathomimetics, such as midodrine, ephedrine, or dihydroxyphenylserine. Supine hypertension has to be considered.

Diagnosis, Differential↗
PubMed1997

Accretion rates of meteorites and cosmic dust in the Early Ordovician.

Abundant fossil meteorites in marine, condensed Lower Ordovician limestones from Kinnekulle, Sweden, indicate that accretion rates of meteorites were one to two orders of magnitude higher during an interval of the Early Ordovician than at present. Osmium isotope and iridium analyses of whole-rock limestone indicate a coeval enhancement of one order of magnitude in the influx rate of cosmic dust. Enhanced accretion of cosmic matter may be related to the disruption of the L chondrite parent body around 500 million years ago.

Calcium Carbonate↗
PubMed1994

2,3,7,8-Tetrachlorodibenzo-p-dioxin inhibits differentiation of normal diploid rat osteoblasts in vitro.

The influence of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent halogenated aromatic hydrocarbon, on the development of bone tissue-like organization in primary cultures of normal diploid calvarial-derived rat osteoblasts was examined. Initially, when placed in culture, these cells actively proliferate while expressing genes associated with biosynthesis of the bone extracellular matrix. Then, post-proliferatively, genes are expressed that render the osteoblast competent for extracellular matrix mineralization and maintenance of structural as well as functional properties of the mature bone-cell phenotype. Our results indicate that, in the presence of TCDD, proliferation of osteoblasts was not inhibited but post-confluent formation of multicellular nodules that develop bone tissue-like organization was dramatically suppressed. Consistent with TCDD-mediated abrogation of bone nodule formation, expression of alkaline phosphatase and osteocalcin was not upregulated post-proliferatively. These findings are discussed within the context of TCDD effects on estrogens and vitamin D-responsive developmental gene expression during osteoblast differentiation and, from a broader biological perspective, on steroid hormone control of differentiation.

Animals↗
PubMed1992

Glucocorticoids promote development of the osteoblast phenotype by selectively modulating expression of cell growth and differentiation associated genes.

To understand the mechanisms by which glucocorticoids promote differentiation of fetal rat calvaria derived osteoblasts to produce bone-like mineralized nodules in vitro, a panel of osteoblast growth and differentiation related genes that characterize development of the osteoblast phenotype has been quantitated in glucocorticoid-treated cultures. We compared the mRNA levels of osteoblast expressed genes in control cultures of subcultivated cells where nodule formation is diminished, to cells continuously (35 days) exposed to 10(-7) M dexamethasone, a synthetic glucocorticoid, which promotes nodule formation to levels usually the extent observed in primary cultures. Tritiated thymidine labelling revealed a selective inhibition of internodule cell proliferation and promotion of proliferation and differentiation of cells forming bone nodules. Fibronectin, osteopontin, and c-fos expression were increased in the nodule forming period. Alkaline phosphatase and type I collagen expression were initially inhibited in proliferating cells, then increased after nodule formation to support further growth and mineralization of the nodule. Expression of osteocalcin was 1,000-fold elevated in glucocorticoid-differentiated cultures in relation to nodule formation. Collagenase gene expression was also greater than controls (fivefold) with the highest levels observed in mature cultures (day 35). At this time, a rise in collagen and TGF beta was also observed suggesting turnover of the matrix. Short term (48 h) effects of glucocorticoid on histone H4 (reflecting cell proliferation), alkaline phosphatase, osteopontin, and osteocalcin mRNA levels reveal both up or down regulation as a function of the developmental stage of the osteoblast phenotype. A comparison of transcriptional levels of these genes by nuclear run-on assays to mRNA levels indicates that glucocorticoids exert both transcriptional and post-transcriptional effects. Further, the presence of glucocorticoids enhances the vitamin D3 effect on gene expression. Those genes which are upregulated by 1,25(OH)2D3 are transcribed at an increased rate by dexamethasone, while those genes which are inhibited by vitamin D3 remain inhibited in the presence of dexamethasone and D3. We propose that the glucocorticoids promote changes in gene expression involved in cell-cell and cell-extracellular matrix signaling mechanisms that support the growth and differentiation of cells capable of osteoblast phenotype development and bone tissue-like organization, while inhibiting the growth of cells that cannot progress to the mature osteoblast phenotype in fetal rat calvarial cultures.

Alkaline Phosphatase↗
PubMed1992

Hepatocellular carcinoma. Prognostic factors and survival analysis in 135 Italian patients.

This is a retrospective study to evaluate the history of hepatocellular carcinoma and find the relationship between clinical, biochemical and ultrasonographic features and survival in Italian patients. In 135 consecutive patients median follow-up was 16 months (range 1-66 months) and median survival from the time of diagnosis was 12 months. Univariate analysis showed that individual variables associated with significantly decreased survival included: absence of therapy, Okuda's Stage III, Child-Pugh's Class C, alpha-fetoprotein greater than 400 ng/ml, presence of symptoms, moderate or severe ascites, tumor involving both lobes, mixed internal echo pattern, and multinodular or massive type. Multiple regression analysis (Cox model) revealed that the mixed internal echo pattern of hepatocellular carcinoma, the presence of moderate or severe ascites and Okuda's Stage III were independent predictors of high risk of death. These data can help in selecting patients whose probability of survival is considered high enough to undergo treatment and may be useful for stratifying patients in randomized controlled trials.

Adult↗
PubMed1989

[Madrepore as a bone filler].

The authors studied the behaviour of the porite type coral which has been previously implanted in man in order to get a reparation of osseous and parodontal defects. The histomorfological exam (at the optical microscope, SEM and X-Ray microscope) of a non decalcified bioptic piece, which had been obtained with an appropriate instrument, shows a deposition of neoformed bone around the coral. Six months after the implantation the tissue was stable without any osteoclasts in activity; even the implanted coral grains had not been attached by them. The Authors agree with most of the statements made by Souyris et Al., but they do not believe in the total substitution of the coral with the bone, at least not in short terms: therefore further scientific works will be necessary to clear this point.

Adult↗
PubMed1984

Resorption of implanted bone prepared from normal and warfarin-treated rats.

Bone that was virtually depleted of the vitamin K-dependent protein, osteocalcin, and 93% reduced in the concentration of its characteristic amino acid, gamma-carboxyglutamic acid, was obtained from rats treated with warfarin for 6 wk. Osteocalcin-deficient bone particles were resistant to resorption when implanted subcutaneously in normal rats. The relative resorption was 60% of control bone, as measured by histomorphometry as percent of bone particles in the field. Additionally, the number of multinucleated cells around the bone particles was reduced by 54%. These data suggest that osteocalcin is an essential component for bone matrix to elicit progenitor-cell recruitment and differentiation necessary for bone resorption.

Animals↗
PubMedDate not supplied

[Hemimandibular reconstruction via an autologous transplant of vascularized fibula. A report of a clinical case].

The authors illustrate the advantage of vascularised as opposed to conventional edges in the reconstruction of the jaw, focusing in particular on the use of a fibular autologous transplant. After a rapid description of the surgical technique used to remove the graft, they report a case of mandibular reconstruction in a young patient who had been involved in a shooting accident which had led to the loss of the left of this jaw.

Adult↗