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Showing papers by "University of Siena published in 1986"


Journal ArticleDOI
TL;DR: It is shown that long-term salmon CT treatment may be of benefit in postmenopausal osteoporosis and that the effects of CT on bone mass may be due not only to the inhibition of bone resorption but also to the stimulation of bone formation.
Abstract: In this paper we present the results of a 12-month double-blind clinical multicenter study assessing the effects of synthetic salmon cacitonin (CT) administration in a group of white postmenopausal osteoporotic women. Treated patients were given 100 MRC units of synthetic salmon CT injected i.m. in the morning every other day. Control patients received a placebo injection. All patients received 500 mg of elementary calcium p.o., b.i.d. Bone mineral content (BMC) was measured at the extreme distal radius of the nondominant arm by a dual photon bone densitometer which utilizes two radionuclides,241Am and125I, with energies of about 60 keV and 30 keV respectively. Biochemical parameters of calcium-phosphorus metabolism were also measured. After 12 months of treatment a significant mean increment of BMC and nondialyzable OHPr/creatinine values and a significant decrease of total OHPr/creatinine values were observed in the treated group, while controls showed a significant decrease in BMC values. These results, together with the observation that in some patients the decrease in total OHPr/creatinine values was not accompanied by an increment of BMC, show that long-term salmon CT treatment may be of benefit in postmenopausal osteoporosis and that the effects of CT on bone mass may be due not only to the inhibition of bone resorption but also to the stimulation of bone formation.

196 citations


Journal ArticleDOI
TL;DR: The rate of 4-hydroxynonenal formation is highest during the very initial phase of its formation and the onset does not show a lag phase, suggesting a transient intermediate predominantly formed during the early phase of microsomal lipid peroxidation.

169 citations


Journal ArticleDOI
TL;DR: It is suggested that bile infection precedes rather than follows the formation of brown stones, and in patients having brown pigment bile stones, recurrent 18 and 36 months after cholecystectomy.

119 citations


Journal ArticleDOI
TL;DR: The cytoplasm of the vegetative cell of the ungerminated pollen grain of Endymton non-scriplus and other angiosperm species contains numerous fusiform bodies, which bind fluorescent-labelled phalloidin and are likely therefore toconstitute a storage form of actin.
Abstract: Dipartimento di Biologia Ambientale, Universita di Siena, Via P. A. Mattioli,53100 Siena, ItalySUMMARYThe cytoplasm of the vegetative cell of the ungerminated pollen grain of Endymton non-scriplusand other angiosperm species contains numerous fusiform bodies sometimes exceeding 15/lm inlength and 2-5 fim in width, which bind fluorescent-labelled phalloidin and are likely therefore toconstitute a storage form of actin. The bodies are dispersed during the activation of the pollen,being replaced by aggregates of slender phalloidin-binding fibrils, which converge towards thegermination apertures and are present in the emerging pollen tube. The storage bodies appear to behomologous with crystalline-fibrillar structures, shown in an earlier paper to be abundantlypresent in the vegetative cells of Nicotiana pollen. These are composed of massive aggregates oflinearly disposed units with individual widths of 4-7 nm, probably to be interpreted as actinmicrofilaments.Vegetative-cell protoplasts from mature but ungerminated pollen disrupted in osmoticallybalancing medium release extended phalloidin-binding fibrils of a kind not observed in the intactgrain. It is suggested that these are derived by the rapid dissociation of the compact actin storagebodies present in the vegetative cell at this stage of development.INTRODUCTION

104 citations


Journal ArticleDOI
TL;DR: In this article, an analysis of the Triassic Verrucano metasediments of the Northern Apennines has been carried out and the authors have reported that the Si content of muscovite and geological arguments, pressures of between 3 and 5 kbar are estimated, with temperatures ranging from 300°C to about 450°C.
Abstract: Mineralogical and petrological studies of Triassic Verrucano metasediments of the Northern Apennines are reported. The widespread occurrence of Al-silicates allows the delineation of four metamorphic zones with increasing metamorphic grade: (1) kaolinite zone (well Perugia 2, Umbria); (2) kaolinite-pyro-phyllite zone (Monte Argentario and part of the Verrucano of the Monticiano-Roccastrada area and Monti Leoni); (3) pyrophyllite zone (Monti Pisani, Iano, Monti Leoni, the Monticiano-Roccastrada area and some wells in the Larderello region); (4) kyanite zone (Massa area and some wells in the Larderello area). The four metamorphic zones correspond to temperatures ranging from 300°C to about 450°C. On the basis of the Si content of muscovite and geological arguments, pressures of between 3 and 5 kbar are estimated. The metamorphic zones are located more or less parallel to the bent north-west-south-east trending structural zonation of the Northern Apennines, with the concave side towards the Tyhrrenian Sea. During the Alpine orogeny, the Verrucano metasediments underwent three folding phases each of which has produced an axial plane schistosity (S1, S2, S3). During the first folding phase the Verrucano sediments were buried increasingly deeply within the crust from east to west. The climax of Alpine metamorphism was attained prior to the second folding phase with crystallization of porphyroblasts of kyanite and chloritoid in a central area located between Massa and Larderello. The inferred paleo-temperature distribution pattern resembles an asymmetric thermal high defined by the kyanite zone, and surrounded by the pyrophyllite zone. A similar pattern is still present in the Tuscan crust, as indicated by a series of geothermal anomalies passing through the Northern Apennines.

94 citations


Journal ArticleDOI
01 Dec 1986-Cancer
TL;DR: The results show the essential prognostic value of morphometry in this set of patients with Stage I renal cell carcinoma, where none of the 24 short‐term survivors are below that threshold and three of the long-term survivors exceed that value.
Abstract: Although 60% of Stage I renal carcinoma patients die from tumor within 5 years postoperatively, a considerable percentage survive that period. Nuclear grading can help to predict the outcome, but many of the patients are Grade 2, and the prognosis of this subclass is uncertain. Therefore, nuclear morphometry was carried out in 41 patients with Stage I renal cell carcinoma. Of these, 24 died within 5 years and 17 have survived that period. Using a mean nuclear area of 32 micron 2 as the decision threshold, none of the 24 short-term survivors are below that threshold and three of the long-term survivors exceed that value (18% false-positives) (99% confidence limit). Separate analysis with sets for learning and testing and Grade 2 patients gave similar results. The results show the essential prognostic value of morphometry in this set of patients with Stage I renal cell carcinoma.

81 citations


Journal ArticleDOI
TL;DR: In this article, the concentrations of some chlorinated hydrocarbon residues (HCB, HCH isomers, p,p'DDT and DDE, PCB congeners) in lichen and moss samples from the Antarctic Peninsula are reported and compared with available data from other parts of the world.

77 citations


Journal ArticleDOI
TL;DR: The aim of the present study has been to elucidate further the cytology of the glandular stigma of Nicotiana tabacum, the mechanism of the secretory process during stigma development and the biochemical composition of the exudate.
Abstract: The aim of the present study has been to elucidate further the cytology of the glandular stigma of Nicotiana tabacum, the mechanism of the secretory process during stigma development and the biochemical composition of the exudate. The stigma consists oftwo distinct zones: a glandular zone formed by the papillae and 2-3 layers of cells (basal cells) immediately below them, and a non-glandular region formed by vacuolated cells which are in continuity with the transmitting tissue. The stigmatic exudate is a complex mixture of different chemical compounds such as proteins, saccharides, fatty acids and phenols. The role of stigma secretion is discussed in relation to pollen activation, recognition and pollen tube growth. THE ANGIOSPERM STIGMA is generally considered a glandular structure whose secretion is important in the pollen-stigma interaction

75 citations


Journal ArticleDOI
TL;DR: One hundred forty-three patients irradiated for locoregional recurrences after curative surgery for cancer of the rectum and sigmoid were studied retrospectively and symptom-free period was calculated as percent of the overall survival.
Abstract: One hundred forty-three patients irradiated for locoregional recurrences after curative surgery for cancer of the rectum and sigmoid were studied retrospectively. An analysis was made of the symptomatic response and survival in the total series and in three subgroups treated with different dose levels (40 Gy or lower, between 40 and 50 Gy, 50 Gy or higher). The symptom-free period was calculated as percent of the overall survival. Symptomatic control was obtained in 80.4 percent of the cases, and the crude patient survival rate was 17.5 percent at two years. No significant difference was found in the three subgroups treated with different dose levels. The cumulative time/patient asymptomatic periods in the total series and in the three subgroups were 31.5, 30.2, 31.8, and 31.9 percent respectively, of the survival period.

70 citations


Journal ArticleDOI
TL;DR: The biological implications of the finding of 4-hydroxynonenal and other carbonyls in vivo in an experimental model of hepatotoxicity are discussed.

62 citations




Journal ArticleDOI
TL;DR: The use of paramagnetic ions, bound to macromolecules and trapped in liposomes, as MRI contrast agents is suggested and the system of Mn2+ bound to serum proteins was tested, finding that the binding of the metal ions to the macromolescules enhances their relaxation and at the same time decreases their rate of diffusion out of the liposome.
Abstract: The use of paramagnetic ions, bound to macromolecules and trapped in liposomes, as MRI contrast agents is suggested. As an example, the system of Mn2+ bound to serum proteins was tested. The binding of the metal ions to the macromolecules enhances their relaxation and at the same time decreases their rate of diffusion out of the liposomes. The use of liposomes is expected to reduce the potential toxicity of the paramagnetic ions and allows their targeting toward specific tissues. © 1986 Academic Press, Inc.

Journal ArticleDOI
A. Caniggia1, R. Nuti1, M. Galli1, F. Lore1, V. Turchetti1, G. Righi1 
TL;DR: Serum bone Gla-protein (BGP or osteocalcin) was measured in 25 women with histologically confirmed postmenopausal osteoporosis before and during long-term treatment with 1 μg/day of 1,25-dihydroxyvitamin D3(1,25(OH)2D3) to determine a specific marker of bone formation.
Abstract: Serum bone Gla-protein (BGP or osteocalcin) was measured in 25 women with histologically confirmed postmenopausal osteoporosis before and during long-term treatment with 1 microgram/day of 1,25-dihydroxyvitamin D3(1,25(OH)2D3). Basal serum BGP was significantly lower in osteoporotic women (3.8 +/- 1.4 ng/ml) than in age-matched controls (6.8 +/- 2.0 ng/ml). During 1,25(OH)2D3 therapy serum BGP increased so that the mean of the values observed on treatment (4.8 +/- 1.5) was significantly higher than the mean basal value. It is known that BGP synthesis is stimulated by 1,25(OH)2D3 and that serum BGP is a specific marker of bone formation; therefore, it is possible that the low basal levels of osteocalcin we observed were related to the low serum 1,25(OH)2D concentrations reported in osteoporotic women and that the increase in BGP levels observed under 1,25(OH)2D3 treatment was a consequence of osteoblast stimulation.

Journal ArticleDOI
TL;DR: In this paper, the paramagnetic species [Co 6 (μ 3 -S) 8 (PEt 3 ) 6 ] (Y ) (Y = BPh 4, (1), PF 6, (2 )).

Journal ArticleDOI
TL;DR: The influence of the foraging area on the intake of trace elements was evaluated in tissues of two species of gull: the black-headed gull and the herring gull.

Journal ArticleDOI
TL;DR: In this article, the mercury concentrations in Pinus nigra, Cedrus atlantica and Cytisus scoparius were determined in the area of Mount Amiata.

Journal ArticleDOI
TL;DR: In this paper, the time dependence of dissolved Hg concentration in rain is discussed to clarify the efficiency of the washout mechanism and anthropogenic Hg emission and the vaporization from cinnabar deposits seem to influence Hg levels in the atmosphere only on a local scale.

Journal ArticleDOI
TL;DR: The presence of a true acrosome in the Homosclerophorida demosponge Oscarella lobularis is described, the first finding of this organelle in Porifera, and the general concepts of the acrosomal evolution are reviewed.

Journal ArticleDOI
TL;DR: An attempt to outline the evolutionary history and detect the starting points for the adaptive radiations of the Acarida is made on the basis of the known elements.
Abstract: In this paper, the present classification and ideas on the evolutionary history of the Acarida are examined. Besides the more usual characteristics relative to the body segmentation, tagmata, tracheae and stigmata, setal birefringency, post‐embryonal development, podocephalic canal and sperm morphology, the fossil remains and the geographic distribution of Acarida are also considered. These data do not give a definite answer to the fundamental question of the acarid phylogeny, namely, whether this group is mono‐or polyphyletic. However, an attempt to outline the evolutionary history and detect the starting points for the adaptive radiations of the Acarida is made on the basis of the known elements. Presumably the early actinotrichid lineages passed onto the land with the terrestrial plant invasion, behaving first either as phytophages on plants, fungal mycelia and bacteria (Actinedida and Oribatida) or as saprophages, probably forming intimate relationships with fungi (Actinedida and Oribatida), ...

Journal ArticleDOI
TL;DR: In economics we commonly have models in search of facts as discussed by the authors, by contrast, long waves appear to be facts-in-search of a model, which makes it more or less impossible to determine any constant system parameters.
Abstract: In economics we commonly have models in search of facts — by contrast, long waves appear to be facts in search of a model. I would like to offer a prospective model. Generally, the shorter the period, the easier it is to explain why a cycle may exist: the best theory is that of the pig cycles, with a period of two lags. Then there is the stocks cycle, the best understood of all generalized economic oscillators. The longer waves of 5–15 years are less evident and have a less agreed-on explanation. Cycles of 40–50 years are difficult to establish and more difficult to explain. To begin with, the 200 or so years of industrial capitalism are too short a time to establish the existence of a cycle from highly disturbed statistical series, so that we do not even know whether there is anything to explain. Second, if a cycle does exist, it is difficult to find a mechanism that remains unchanged for that long a time to produce a cycle. The pronounced turbulence of modern capitalism makes it more or less impossible to determine any constant system parameters.

Book ChapterDOI
01 Jan 1986
TL;DR: The Mediterranean is a semi-enclosed basin with only limited water exchange with the Atlantic ocean through the Straits of Gibraltar as mentioned in this paper, and the Mediterranean is the most important water source in the world.
Abstract: The Mediterranean is a semi-enclosed basin with only limited water exchange with the Atlantic ocean through the Straits of Gibraltar.

Book ChapterDOI
01 Jan 1986
TL;DR: In this article, the authors use truncations to investigate universal covers of geometries with non-spherical minimal circuit diagrams, and show how truncations can be used to study covers.
Abstract: In this paper we want to show how truncations can be used to study covers. In particular, we use trucations to investigate universal covers of geometries with non-spherical minimal circuit diagram.

Journal ArticleDOI
TL;DR: The results of a long term monitoring of mercury, cadmium, lead and selenium and their interactions in tissues of the Black-necked grebe wintering in the lagoon of Marano (NE Italy), an environment moderately polluted by mercury are reported.
Abstract: Recent papers have demonstrated that water birds collected in the Mediterranean area accumulate remarkable amounts of mercury, usually greater than in the same species obtained from other areas. The critical exposure to the pollutant could negatively influence the survival of some species of birds, particularly those high in the food chain. Nevertheless animals belonging to various phyla have the ability to adapt themselves to environmental-pollutant damage. Of the various defense mechanisms employed by birds and mammals, the retention of selenium as an antagonist to mercury toxicity is the best known. In the present paper the authors report the results of a long term monitoring of mercury, cadmium, lead and selenium and their interactions in tissues of the Black-necked grebe (Podiceps nigricollis) wintering in the lagoon of Marano (NE Italy), an environment moderately polluted by mercury.

Journal ArticleDOI
TL;DR: In this article, the electrochemical behavior of a series of mono-nuclear, homo-and hetero-dinuclear complexes of dioxouranium(VI), nickel(II) and copper (II) ions with acyclic and cyclic compartmental ligands, derived from the condensation of 2,6-diformyl-4-chlorophenol and polyamines of the type NH 2 (XNH, S), is reported.

Book ChapterDOI
01 Jan 1986
TL;DR: The structure of the peritoneum has been studied by scanning and transmission electron microscopy and by light microscopy in 38 biopsies of 22 patients undergoing CAPD and after recovery the mesothelium is replaced by thick fibrous connective tissue.
Abstract: The structure of the peritoneum has been studied by scanning and transmission electron microscopy and by light microscopy in 38 biopsies of 22 patients undergoing CAPD. Before CAPD the mesothelium was characterized by flattened cells with protruding nuclei, numerous microvilli and many pinocytotic vesicles. After prolonged CAPD there is a reduction and subsequent disappearance of microvilli and a vacuolar separation of cells from the basement membrane, accompanied by widening of intercellular junctions. Neither ultrafiltration rate nor small solute clearance change with these structural alterations. During peritonitis there is extensive cellular necrosis with denuding of the basement membrane. After recovery the mesothelium is replaced by thick fibrous connective tissue.

Journal ArticleDOI
TL;DR: It is concluded that a direct action of gossypol on epididymal spermatozoa is superimposed on the action earlier exerted on the spermatids.
Abstract: Adult male Sprague-Dawley rats were fed daily with 25 mg/kg of gossypol acetic acid for 55 days. The examination of the testis revealed the constant integrity of the blood-testis barrier. The earliest damage to the germinal cells appeared on the 14th day of treatment in spermatids in stage 18-19, and consisted of mitochondrial swelling and cristae disorganization, which was manifested in an altered assembly of the mitochondrial helix and possible axonemal alterations. It appeared that the target cell was a 30–37-day-old spermatid that showed the first alterations 6–14 days later, when it reached stage 18. The mitochondrial and eventual axonemal damage was conserved after the migration into the epididymis, affecting 6% of the total sperm population on the 14th day of treatment and reaching the maximum (100%) on the 25th day of treatment. On the 5th day of treatment, epididymal spermatozoa revealed, moreover, the presence of other tail alterations: lack of half of the axonemal components (also in sperm with unaffected mitochondria), loss of midpiece plasma membrane, and breaking of the outer accessory fibers. The conclusion is that a direct action of gossypol on epididymal spermatozoa is superimposed on the action earlier exerted on the spermatids.

Journal ArticleDOI
TL;DR: The alterations observed in the peripheral nervous system are probably secondary to a lesion of the posterior root ganglion and the anterior horn cell in the spinal cord.
Abstract: We report the findings of an electrophysiological study in 9 patients affected by olivopontocerebellar atrophy, 4 with a dominant form and 5 with a sporadic form. Superficial peroneal nerve biopsy was obtained from 2 patients. The electrophysiological alterations were signs of collateral reinnervation and loss of motor units, decrease in sensory potential amplitude and increase in distal motor latency. Only a slight reduction in motor and sensory conduction velocity was observed in some cases. Nerve biopsy showed slight reduction of the number of myelinated fibres. In the first case, fibre diameter distribution was unimodal, due to reduction of myelinated fibres of large diameter, in the second case there was no significant alteration of the fibre distribution. In both cases short internodes were present with no signs of segmental demyelination, remyelination or axonal degenaration. The alterations observed in the peripheral nervous system are probably secondary to a lesion of the posterior root ganglion and the anterior horn cell in the spinal cord.

Journal ArticleDOI
TL;DR: The result suggests that when ovulation occurs, plasma beta-EP levels show a relevant rise, the physiologic significance of which remains to be elucidated.

Book ChapterDOI
TL;DR: Type II tyrosinaemia in Italy has no regional preponderance and treatment with a low tyrosine diet has been successful when accepted, but since in many patients the diagnosis was made rather late, it is not possible to evaluate the results of the diet for the prevention of neuromotor retardation.
Abstract: Hereditary type II tyrosinaemia (McKusick 27660) is an autosomal recessive disorder characterized by hypertyrosinaemia and tyrosyluria, without signs of hepatic and renal damage. The patients have a dendritic keratopathy, painful hyperkeratosis of the palms and soles and sometimes mental retardation. Hypertyrosinaemia with values ranging from 14 to 62mgdl−1, tyrosinuria and tyrosyluria are found. A defect of hepatic tyrosine aminotransferase (EC 2.6.1.5) in the cytosol is considered to be the molecular abnormality (Kennaway and Buist, 1971; Goldsmith et al., 1979).