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Biomedical subjects

S Zecchi

Publications and source records attributed to S Zecchi.

18 recordsLinked to original sources
PubMed1997

Heterogeneity of binding sites and bioeffects of raloxifene on the human leukemic cell line FLG 29.1.

The benzothiophene divarative raloxifene is known to mimic estrogen in human bone remodeling. To investigate the "in vitro" properties of raloxifene on osteoclast precursors, the human leukemic cell line FLG 29.1, which differentiates toward the osteoclastic phenotype, was examined for raloxifene binding and for evidence of its bioeffects. Scatchard and Hill analysis of binding data with the tritiated raloxifene demonstrated the presence of two classes of binding sites in both nuclear and cytosol fractions with Kd values of approximately 1 nM and approximately 5 nM, respectively. In addition, analysis of binding data using tritiated 17 beta E2 as ligand at high concentrations (10-40 nM) and either unlabeled 17 beta E2 or raloxifene as competitors gave similar results demonstrating the presence of type II EBS in these cells. Picomolar concentrations of raloxifene significantly (p < 0.05) inhibited cell proliferation. Moreover, the compound at nanomolar concentrations induced a significant dose- and time-dependent increase of progesterone receptor, and activated apoptotic cell death. These findings clearly demonstrate that raloxifene acts as an estrogen agonist in FLG 29.1 cells, acting through the estrogen receptor and, possibly, via multiple cooperative binding component(s).

Apoptosis↗
PubMed1997

HPE cells: a clonal endothelial cell line established from human parathyroid tissue (human parathyroid cell line).

We report the culture and cloning of human endothelial cells derived from parathyroid tissue surgically removed from a patient affected by Multiple Endocrine Neoplasia Type 1 syndrome. These cells, known as HPE, have been isolated and maintained in culture by serial passages for more than 15 months. The clonal cell line grows in a medium containing serum substitutes which favour endothelial cell growth. HPE cells replicate with a mean doubling time of 120 h, showing typical functional and morphological features of endothelial cells, such as uptake of acetylated low density lipoprotein and positive reaction for Factor VIII-Related Antigen. Basic fibroblast growth factor, vascular endothelial growth factor, insulin-like growth factor type I and ascorbic acid stimulate cell proliferation, whereas transforming growth factor beta and heparin act as inhibitory factors. Prostaglandin E2, secretin and epinephrine increased cAMP production, while human parathyroid hormone, histamine and glucagon were inert. Cells were found to express pro-collagen alpha 1 (type I) mRNA. In HPE cells Restriction Fragments Length Polymorphism and PCR analysis did not show allelic loss at chromosome 11q12-13, known to be a typical feature of MEN 1 parathyroid tumors. These cells are the first example of an established normal human clonal cell line with an endothelial phenotype.

Cell Division↗
PubMed1995

[Role of slime in the pathogenesis of pulmonary infections].

Microorganisms have proved to produce an amorphous substance that adheres to surfaces of several medical devices like intravenous catheters and endotracheal tubes. We investigated the presence of slime in endotracheal tubes in our Intensive Care Unit (ICU) in 12 patients. We found in this study no correlation between the strain of bacteria on the surface of endotracheal devices and those responsible for pneumonia.

Adult↗
PubMed1983

[Statistical findings on scalp hair as observed by scanning electron microscopy].

The scalp hair of hundred, 20-year-old, healthy human blond and dark volunteers (50 males and 50 females) have been studied by means of scanning electron microscopy. On the photographs, taken at right angles to the length of the hair and always at the same magnification, some measurements have been performed: 1) the hair diameter, 2) the mean scale height, 3) the mean scale number, 4) the scale index and 5) the mean scale width. The obtained data were submitted to a statistical elaboration which gave the following results: a) the hair diameter and the cuticular scale patterns do not show statistically significant differences between males and females and blond and dark subjects; b) an inverse correlation exists between the height and the number of the scales; c) the hair diameter is correlated inversely with the mean scale height and directly with the mean scale number and width.

Adult↗
PubMed1983

[Statistical study of the anatomo-radiologic characteristics of the sphenoid sinus and sella turcica].

On 300 human cranial radiograms (150 males and 150 females) the three dimensions and the volume of the sphenoidal sinus and sella turcica as well as the cranial diameters have been measured. The male/female differences in the mean values for each diameter and for the volumes, assayed by Student's t test, indicate a male preponderance in the case of the sphenoidal sinus. No significant correlation seems to relate the sizes of the sphenoidal sinus and sella turcica with the Cranial Index and the cranial diameters. Furthermore, no significant correlation has been found relating the size of the sphenoidal sinus with that of the sella turcica.

Adolescent↗
PubMed1982

The behaviour of some human arteries as regards the corrected circumference: a statistical research.

In 500 human fresh cadavers (250 males and 250 females) the corrected circumference has been measured of the following arteries: aorta, coronary arteries, branches of the aortic arch, arteries of the base of the brain, iliac arteries. Elaborating these data by a computer, the following age power function, expressing the arterial circumference, has been found: y = Kxn less than 1, being y the corrected circumference, x the age and K and n constants, specific for each artery. By means of this equation the inconstancy of the measured data has been suppressed. The statistical elaboration has given the following results: 1. No evidence has been found on a statistically significant difference between male and female arteries, even if the male sex has generally vessels a little larger than the female sex. 2. No evidence has been found on a statistically significant difference between right and left arteries, even if, generally, the right vessels are a little larger than the left ones. On the other hand, for the coronary arteries and for the vertebral arteries, the left side is prevalent. 3. As a general statement, there is evidence that the arterial circumference of considered vessels increases with ageing.

Adult↗
PubMed1981

Statistical research on the corrected circumference variations of some human arteries related to sex, side and age.

The corrected circumference of the common and internal carotid arteries, the subclavian arteries, the common, external and internal iliac arteries has been measured in 500 human fresh cadavers. The collected data have been statistically elaborated and the age power function (y = k x n less than 1) has been found. Generally no significant difference has been noticed between the right and the left side as well as between the two sexes. As a general statement, there is some evidence that the arterial circumference of considered vessels increases progressively with ageing.

Adult↗
PubMed1981

On the granulosa cells of ovarian follicles. I. Morphometric research on the relationship between granulosa and theca interna in evolutive follicles.

In the aim of detecting some morphological relationship between granulosa and theca interna layers in evolutive follicles of different mammalian species, a morphometric research has been carried out. In the follicles, classified according to their size, the thickness of the thecal layer has been measured at the pole of the follicle corresponding to cumulus oophorus and at the opposite side. The obtained results have been statistically analyzed. At the level of the cumulus oophorus the thickness of the theca interna layer results to be higher than in the opposite side during all the life-span of the evolutive follicles.

Animals↗
PubMed1981

On the granulosa cells of ovarian follicles. II. Identification of different morphological patterns of granulosa cells in evolutive follicles.

An attempt has been made for identifying different types of granulosa cells in the wall of cavitary ovarian follicles. Human, porcine and rat ovaries have been examined at the light and electron microscopes. Some smears of granulosa cells as well as human foetal ovaries have been also studied. These preliminary results seem to confirm that in the granulosa layer of evolutive follicles the cells may present some different morphological and histochemical features.

Animals↗
PubMed1981

On the structural changes of granulosa cells cultured in vitro. Histochemical, ultrastructural and stereological observations.

Granulosa cells from porcine ovarian follicles were cultured in vitro in standard medium and in medium supplemented with HCG. After culture the cellular 3 beta HSD enzymatic activity was evaluated and the cells were studied by TEM and SEM. A stereological evaluation of the smooth and rough endoplasmic reticulum was carried out. The results indicate that the cultured cells undergo a luteinization process which is more evident in the presence of HCG. In fact, in comparison with the controls, in these cells the enzymatic activity is higher, the rough endoplasmic reticulum decreases and the smooth endoplasmic reticulum increases, the cytoplasm shows lipid droplets and vesicular mitochondria. The cell surface develops a number of microvillus-like evaginations.

Animals↗
PubMed1978

[Action of HCG on isolated and cultivated sow ovarian granulosa cells].

Granulosa cells harvested from cavitary follicles of varying diameters have been cultivated in vitro in basic conditions and in presence of HCG, and then tested for the activity of steroid-3 beta-ol-dehydrogenase and observed with a scanning electron microscope. As concerns the enzymatic activity, the cells of the smaller follicles (5--6 mm) show a very low reactivity which increases in presence of HCG. In the cells of the larger antral follicles (8--9 mm) the reactivity is remarkably higher, particularly when HCG is added to the medium. With the scanning electron microscope the appearance of the granulosa cells of the larger follicles cultivated with HCG is very peculiar because of the presence on the cell surface of many cytoplasmic evaginations. These are more numerous and thinner than those normally found on the uncultured cells and on the cells cultivated in basic conditions.

3-Hydroxysteroid Dehydrogenases↗
PubMedDate not supplied

Vas deferens and seminal vesicles epithelium after castration: a SEM study.

The effects of orchiectomy have been observed, with SEM, on the vas deferens and seminal vesicles epithelium of 20 adult albino rats. The inner surface of castrated rat vas deferens shows a reduction in height and thickness of the mucosal folds and, at the cellular apex, a remarkable decrease of the microvilli as well as the disappearance of the secretory blebs. At the level of the seminal vesicles also, castration affects both the mucosal folds, which are flattened, and the cellular apical features, with the reduction of the microvilli and the disappearance of the secretory granules. Such changes give evidence in favour of a decrease in the absorptive capacity and a suppression of the secretory activity of these epithelia, as a consequence of the fall of androgen levels.

Animals↗