Showing papers by "University of Siena published in 1995"

The modified papilla preservation technique. A new surgical approach for interproximal regenerative procedures.

Abstract: A modification of the papilla preservation technique has been applied to achieve primary closure of the interproximal tissue over barrier membranes placed coronal to the alveolar crest. Fifteen patients with deep intrabony interproximal defects were treated. Defects had a probing attachment level loss of 9.9 +/- 3.2 mm and a recession of the gingival margin of 1.7 +/- 1.6 mm. The depth of the intrabony component was 5.5 +/- 2.9 mm; while the suprabony component was 5.9 +/- 2.0 mm. Titanium-reinforced teflon membranes were placed 1.3 +/- 0.7 mm from the cemento-enamel junction, 4.5 +/- 1.6 mm coronal to the interproximal alveolar bone crest. Primary closure over the interproximal portion of the membrane was obtained in 93% of cases. In 73% of the cases complete coverage of the membrane was maintained until its removal at 6 weeks. These data indicate that the modified papilla preservation technique can be successfully applied to obtain primary closure of the interdental space in regenerative procedures with barrier membranes.

Cloning of the gene for ocular albinism type 1 from the distal short arm of the X chromosome

Abstract: Ocular albinism type 1 (OA1) is an X–linked disorder characterized by severe impairment of visual acuity, retinal hypopigmentation and the presence of macromelanosomes. We isolated a novel transcript from the OA1 critical region in Xp22.3–22.2 which is expressed at high levels in RNA samples from retina, including the retinal pigment epithelium, and from melanoma. This gene encodes a protein of 424 amino acids displaying several putative transmembrane domains and sharing no similarities with previously identified molecules. Five intragenic deletions and a 2 bp insertion resulting in a premature stop codon were identified from DMA analysis of patients with OA1, indicating that we have identified the OA1 gene.

Relationships between the Tertiary structural evolution of the Sardinia-Corsica-Provençal Domain and the Northern Apennines

Abstract: Based on a revision of stratigraphic and structural data relative to the Balearic basin, the Corsica-Sardinia massif, the Northern Tyrrhenian Sea and the Northern Apennines the following new hypothesis is proposed for the area located between the Sardinian-Corsican-Provencal and Northern Apennines regions: (a) convergence with subduction of oceanic crust under the Iberian plate beginning in the Late Cretaceous; (b) continental collision in the Oligocene-Aquitanian, with development of the Northern Apennines belt and transpressive deformation in a hinterland that consisted of the Corsica-Sardinia massif (still attached to the Iberian plate); (c) in the Burdigalian the tectonic regime changed from compressive to extensional. During this period the Corsica-Sardinia massif migrated contemporaneously with opening of the Balearic basin, the Sardinian rift, and the Northern Tyrrhenian sea; (d) from the Burdigalian to the present, there was contemporaneous compression at the front and extension at the back of the Northern Apennines chain; both these features progressively migrated toward the east. The coeval extension and compression is attributed to lithospheric delamination toward the external part of the belt.

Periodontal regeneration of human intrabony defects with titanium reinforced membranes. A controlled clinical trial.

Abstract: The purpose of this controlled clinical trial was to compare the clinical efficacy of 3 treatment modalities in the treatment of deep interproximal intrabony defects. Forty-five (45) defects in 45 patients were randomly assigned to 1 of 3 treatment groups by blocking to prognostic variables. The test group was treated with titanium reinforced membranes positioned just apical to the cemento-enamel junction and the modified papilla preservation technique; the second group received conventional expanded polytetrafluoroethylene (ePTFE) barrier membranes applied at the alveolar crest; the third group was treated with an access flap procedure. The groups were well balanced with respect to all prognostic variables. During the 1-year observation period, patients were subjected to a stringent infection control program including: professional tooth cleaning every week for the first 6 weeks (all groups) and in the 4 weeks following membrane removal (guided tissue regeneration groups), then at monthly intervals (all groups). The results indicated that: 1) all treatment modalities resulted in clinical and statistically significant improvements in clinical attachment level (CAL) and probing depths (PD) at 1 year; 2) a significantly greater amount of CAL gain (P = 0.0003, analysis of variance) was observed in the test group (5.3 +/- 2.2 mm) with respect to both the ePTFE group (4.1 +/- 1.8 mm) and the flap control group 2.5 +/- 0.8; 3) in the test group the 1 year CAL (4.7 +/- 1.8 mm) was located more coronally than the baseline position of the interproximal alveolar crest (5.9 +/- 2 mm; P = 0.003, t test).(ABSTRACT TRUNCATED AT 250 WORDS)

Recurrence of Bleeding in Patients With Primary Intracerebral Hemorrhage

Abstract: Background and Purpose Rebleeding in patients with primary intracerebral hemorrhage is considered uncommon, but there are no precise data to support this opinion The purpose of this study was to assess the incidence and predictors of recurrent bleeding in survivors of primary intracerebral hemorrhage Methods As part of a prospective study, 112 survivors of a first primary intracerebral hemorrhage were followed up for a mean period of 841 months after their discharge To ascertain risk factors that may influence rebleeding, several demographic, medical history, clinical, and laboratory variables were collected and analyzed Results Twenty-four percent (27/112) of survivors experienced one or more rebleedings during the follow-up period, in 8 cases (30%) in the first year of follow-up; in the others recurrence occurred later, up to 115 years Rebleeding had a high mortality rate: 70% of patients died as a consequence of their second or third hemorrhage Univariate and multivariate analyses showed that l

Wood dust and sino-nasal cancer: pooled reanalysis of twelve case-control studies

Abstract: In order to examine the relationship between wood dust and sino-nasal cancer, data from 12 case-control studies conducted in seven countries were pooled and reanalyzed. The relative risks associated with wood-related jobs and with exposure to wood dust, measured using a job exposure matrix based on occupation and industry titles, were examined using logistic regression. The combined data set consisted of 680 male cases, 2,349 male controls, 250 female cases, and 787 female controls. A high risk of adenocarcinoma among men was associated with employment in wood-related occupations (odds ratio [OR] = 13.5, 95% confidence interval [CI] = 9.0-20.0) and the risk was greatest among men who had been employed in jobs with the highest wood dust exposure (OR = 45.5, 95% CI = 28.3-72.9) and increased with duration of exposure. The risk of adenocarcinoma also appeared elevated among women employed in wood-related jobs (OR = 2.5, 95% CI = 0.5-12.3), but the small number of exposed cases precluded detailed analysis. Women in wood dust-exposed jobs appeared to have an excess of squamous cell carcinoma (OR = 2.1, 95% CI = 0.8-5.5) which increased with duration of exposure. An increased risk of squamous cell carcinoma in men was seen only among those employed for 30 or more years in jobs with exposure to fresh wood (OR = 2.4, 95% CI = 1.1-5.0). The results of this analysis provide strong support to the association between exposure to wood dust in a variety of occupations and the risk of sino-nasal adenocarcinoma and are consistent with the results of individual participating studies, although the magnitude of the excess risk varied. The evidence in regard to squamous cell carcinomas was ambiguous and there was a great deal of heterogeneity observed in individual study results. This may be due to differences in risk associated with exposure to hardwoods and softwoods or with other, as yet to be identified, aspects of exposure.

Neuropeptides in skin

Abstract: Neuropeptides are a heterogeneous group of more than 50 molecules that play a role in various cutaneous functions and diseases; they act as neuromodulators, neurotransmitters, neurohormones, and hormones In the skin, neuropeptides are synthesized locally (ie, in keratinocytes and in endothelial cells) and are transported by nerve fibers or immune cells (ie, lymphocytes, monocytes, and polymorphonuclear cells) Specific receptors and binding sites for neuropeptides have been described in different cell lines in the skin (keratinocytes, endothelial cells, immune cells, fibroblasts) Many different biologic actions of neuropeptides have been demonstrated Depletion of cutaneous neuropeptides (ie, with capsaicin cream) or therapeutic use of neuropeptide agonists and/or antagonists may aid in the treatment of skin diseases

Immunogold localization of arabinogalactan proteins, unesterified and esterified pectins in pollen grains and pollen tubes ofNicotiana tabacum L.

Abstract: The monoclonal antibodies JIM 5 (against unesterified pectin), JIM 7 (against methyl esterified pectin), MAC 207 (against arabinogalactan proteins, AGPs), and JIM 8 (against a subset of AGPs) were utilized singly or in combinations for immunogold labelling of germinated pollen grains and pollen tubes ofNicotiana tabacum. Pectins were localized in the inline of pollen grain, unesterified pectin being more abundant than the esterified one. AGPs were co-localized with pectin in the inline, but were present preferably close to the plasma membrane. In pollen tubes, AGPs, unesterified and esterified pectins were co-localized in the outer and middle layers of the cell wall. The density of the epitopes was not uniform along the length of the pollen tube, but showed alterations. In the pollen tube tip wall esterified pectin was abundantly present, but not AGPs. In the cytoplasm esterified pectin and AGPs were detected in Golgi derived vesicles, indicating their role in the pathway of the cell wall precursors. In the “cell wall” of generative cell only AGPs, but no pectins were localized. The co-localization of pectins and AGPs in the cell wall of pollen grain and pollen tube might play an important role, not only in maintenance of the cell shape, but also in cell-cell interaction during pollen tube growth and development.

Periodontal regeneration of intrabony defects: an evidence-based treatment approach.

Abstract: A task force of periodontists established clinical and histologic outcomes (goals) for the treatment of intrabony defects and researched the literature for techniques that would most predictably achieve these goals. The group also identified factors that could influence predictability. The treatment outcomes selected by the task force included regeneration of a true attachment apparatus; gain in bone and probing attachment levels; reduction in probing pocket depth; minimal gingival recession; increased patient comfort; esthetic appearance and state of wellness; and maintenance of health, comfort, and function over time. Based on evidence, it was concluded that guided tissue regeneration, guided tissue regeneration combined with the use of decalcified freeze dried bone allografts and freeze-dried bone allografts alone are the most predictable regenerative procedures for achieving selected treatment outcomes. Various factors, such as patient characteristics, the morphology of the defect, and the surgical technique can influence the healing response of intrabony defects. Patient factors, such as plaque control, compliance, and cigarette smoking, can directly affect predictability of periodontal regeneration. Defect selection is critical, and deep and narrow defects are the most predictable response to regenerative procedures. The number of remaining bony walls is important in grafting procedures, but their influence is questionable in guided tissue regeneration. Various technical procedures, such as flap design, defect debridement, and wound protection, may influence the predictability of regeneration.

Habitat use and ranging behaviour of the red fox (Vulpes vulpes) in a Mediterranean rural area: is shelter availability a key factor?

Abstract: Factors affecting activity, habitat use, and home-range size of the red fox were analysed in a highly heterogeneous rural environment. Individual differences in behaviour were used to test our hypotheses. Food habits tended to depend on food availability, which, in turn, was mainly influenced by temperature. Diet was highly heterogeneous. Insects, e.g. grasshoppers and beetles, and cultivated fruits were the staple of the diet, but no diet component stood out clearly from all others. For an opportunistic species such as the fox, habitat heterogeneity may be the main factor underlying a wide trophic niche. All foxes selected the vineyard as part of their home ranges, whereas they preferred for activity the abandoned olive-yard among the habitats of their home ranges. Human intolerance of foxes affects their pattern of activity, habitat selection, and ranging behaviour. Foxes were strongly nocturnal. Cover-rich habitats were preferred for resting and for movements in daylight. Areas under human management were mainly used at night. Selectivity was higher for resting than for activity sites. Variation in home-range size and shape can be influenced not only by the dispersion of the main food patches, but also by the location of shelters

Helicobacter pylori-specific CD4+ T-cell clones from peripheral blood and gastric biopsies.

Abstract: Colonization of human gastric mucosa with cytotoxic strains of the bacterium Helicobacter pylori is associated with peptic ulcer and with chronic gastritis. Since little is known about the T-cell response to H. pylori, we investigated the CD4+ T-cell response both in peripheral blood mononuclear cells (PBMCs) and at the site of infection. First, we compared the bulk PBMC proliferative response to the bacterium in individuals with and without symptoms of gastroduodenal disease. We found that the PBMCs from virtually all individuals proliferate in response to heat-inactivated bacteria. Second, we cloned H. pylori-specific CD4+ T lymphocytes from the PBMCs of three patients and from both the gastric mucosa and PBMCs of a fourth patient. We have found that CD4+ T-cell clones specific for H. pylori from peripheral blood samples and gastric mucosae of infected patients are major histocompatibility complex class II restricted and discriminate between several cytotoxic and noncytotoxic bacterial strains. Moreover, they are polyclonal in terms of T-cell receptor usage and major histocompatibility complex restriction. Our results demonstrate that the T-cell response to the whole bacterium in PBMCs does not correlate with antibody response, infection, or disease. However, H. pylori-specific CD4+ T cells are detectable, at the clonal level, in both the periphery and gastric mucosa of infected patients. Localization of these cells at the site of disease suggests they are effectors of the immune response to the bacteria.

Molecular cloning and characterization of profilin from tobacco (Nicotiana tabacum): increased profilin expression during pollen maturation.

Abstract: Profilin has recently been identified as an actin-binding protein in higher plants. A cDNA coding for tobacco profilin, which shared an average sequence identity of 75% with other plant profilins, was isolated from a tobacco pollen cDNA library by antibody screening. Tobacco profilin was expressed in Escherichia coli and purified by affinity to poly-(L-proline) Sepharose. A rabbit antiserum was raised against recombinant tobacco profilin and used to estimate the amount of profilin expressed in different tobacco tissues. Profilin can be detected in different somatic tissues, but the expression is 50–100 fold higher in mature pollen. Immunofluorescence and confocal laser scanning microscopy showed a homogeneous distribution of profilin in the cytoplasm of in vitro cultured pollen grains and pollen tubes of tobacco whereas some growing pollen tubes were stained more intensively a their tip. A possible role of pollen profilin as a developmentally upregulated microfilament precursor in mature pollen is discussed.

A Petri Net Semantics for pi-Calculus

Abstract: A distributed semantics for π-calculus, based on P/T Petri nets with inhibitor arcs, is presented. This net semantics is sound w.r.t. the original early transition system semantics: the interleaving semantics of an agent p is retrievable from the net by considering the interleaving marking graph for the associated marking dec(p). Furthermore, π-calculus is equipped with a multistep and a causal semantics. The latter is compared with recent proposals appeared in the literature.

Hypertension and primary hyperparathyroidism : the role of adrenergic and renin-angiotensin-aldosterone systems

Abstract: Primary hyperparathyroidism (HPTH) is frequently associated with hypertension. To date, the relationship between these two conditions is still not clear. We have studied 34 consecutive patients with primary HPTH due to a parathyroid adenoma. The diagnosis was later surgically confirmed in 32 cases. Ten of thirty-four HPTH patients were hypertensive. Before adenomectomy (PTHX) and 1-2 months after PTHX, we measured the following parameters in all patients: circulating levels of total and ionized Ca, intact immunoreactive parathormone (iPTH) (1-84), plasma renin activity (PRA), aldosterone, and daily total urinary catecholamine excretion. Moreover, 10 hypertensive HPTH patients, 10 normotensive HPTH patients, compared to 10 to 10 sex- and age-matched healthy normotensive subjects, underwent an acute norepinephrine test to assess vascular reactivity to a pressor agent. Before PTHX, no significant difference was observed between normotensive and hypertensive patients in all the above-mentioned variables, except for PRA and plasma aldosterone levels which were higher in hypertensive patients. Furthermore, the pressor response to the norepinephrine test was significantly greater in hypertensive HPTH patients than in the other 2 groups. After PTXH, serum Ca and intact iPHT (1-84) levels were reduced to normal values in all patients, while blood pressure, PRA and plasma aldosterone levels became normal in 8 of 10 hypertensive patients. The pressor response to the norepinephrine test was similar in the 2 groups. These results are consistent with the hypothesis of a direct effect of PTH on renin secretion which could contribute to the pathogenesis of hypertension and to the vessels sensitization to pressor agents.

Diagnostic value of ultrasound analysis and bone densitometry as predictors of vertebral deformity in postmenopausal women.

Abstract: Bone fractures depend not only on bone density, but also on bone quality. Ultrasound (US) has been proposed as a technique for evaluating skeletal status. Speed of sound (SOS) and broadband ultrasound attenuation (BUA) are the US properties currently used to assess bone strength and fragility. In 304 postmenopausal women (age 58.8±5.5 years) we measured: bone mineral density (BMD) of the lumbar spine (by dual-energy X-ray absorptiometry), SOS, BUA and Stiffness in the os calcis (using an Achilles machine). In all subjects we performed lateral lumbar and thoracic radiographs. Morphometric parameters were derived by measuring the anterior, middle and posterior height of each vertebral body, to obtain a semiquantitative grading of vertebral fractures as follows: 0, no vertebral deformity; 1, any vertebral height reduced between 20% and 25%; 2, any vertebral height reduced between 25% and 40%; 3, any vertebral height reduced more than 40%. On the basis of the number and severity of vertebral deformities the women were divided into: group 1 (n=79), normal; group 2(n=80), mild; group 3 (n=85), moderate; and group 4 (n=60), severe. Mean values of SOS, BUA, Stiffness and BMD were significantly lower (p<0.001) in women with vertebral deformity than in normals. In the whole population SOS, BUA and Stiffness values were significantly correlated with BMD. SOS, BUA and Stiffness values were significantly decreased (p<0.001) with vertebral deformity, as was BMD. Receiver operating characteristic (ROC) curve analysis showed BMD to be slightly better than Stiffness in discriminating among groups. Logistic regression analysis showed that BMD, BUA, SOS and Stiffness were independent predictors of vertebral fracture risk. Ultrasound parameters were still significant independent predictors of vertebral fracture even after adjusting for BMD.

Hypersingular boundary integral equations have an additional free term

Abstract: In this paper it is shown that hypersingular boundary integral equations may have an additional free term which has been erroneously omitted in former analyses.

Notulae seminologicae. 5. Mathematical evaluation of interdependent submicroscopic sperm alterations.

Abstract: This paper concerns the mathematical evaluation of sperm quality as examined by electron microscopy. Proceeding with a Bayesian technique, we have developed a formula considering all statistical possibilities for defects of the examined sperm to be present in a sperm cell, the total number of affected spermatozoa, and, as consequence, that of sperm devoid of defects, also considering the probability of association characteristics of some of them. The formula has been studied in three applications. The first concerns the number of healthy spermatozoa present in ejaculates of fertile men. We have found an enormous variability, but we have observed that the minimal number of spermatozoa free of defects assuring a normal fertility seems to be a little higher than 2 x 10(6). The second and third examples concern varicocele and assisted fertilization. In both cases the formula allows a precise simultaneous evaluation of the totality of studied characters and a determination of the number of spermatozoa free from defects. This comparative analysis shows that the formula is sufficiently sensitive to distinguish the different degrees of the varicocele condition and the various possibilities of fertility power in cases of natural or artificial insemination. In this way we will easily control the level of improvement of sperm quality in cases of varicocele treated pharmacologically or surgically, or we will better predict the success of artificial insemination.

Novel, potent, and selective 5-HT3 receptor antagonists based on the arylpiperazine skeleton: synthesis, structure, biological activity, and comparative molecular field analysis studies.

Abstract: Synthesis and pharmacological evaluation of a series of condensed quinoline derivatives bearing a basic nitrogen on piperazine or [(dimethylamino)ethyl]thio moieties attached at the 2-position of the quinoline nucleus are described. 5-HT receptor binding studies revealed, for most of the compounds studied, nanomolar affinity for the 5-HT3 receptor subtype. The most active compound, benzopyrano[3,4-c]quinoline derivative 5f, displayed a Ki value very similar to that reported for quipazine along with an improved selectivity. Functional and in vivo testing carried out on three selected compounds showed that 5f,j,n are potent 5-HT3 receptor antagonists with potencies in the same range as the best known 5-HT3 receptor antagonists ondansetron, tropisetron, and zacopride. The crystal and molecular structures of compounds 5f,j,n were determined by single-crystal X-ray diffraction and used as starting structures for molecular modeling studies. Comparative molecular field analysis (CoMFA) was applied to binding constants of compounds 5a-p and 6a-h. The cross-validated r2, derived from partial least-squares calculations, indicated a good predictive capacity for affinity values in the series of compounds investigated. Evidence for the prediction capacity is provided in the form of plots of actual vs predicted pKi values. The steric and electrostatic features of the CoMFA-derived model are presented as standard coefficient contour maps of steric and electrostatic fields.

The arterial blood supply of the pancreas: a review. I. The superior pancreaticoduodenal and the anterior superior pancreaticoduodenal arteries. An anatomical and radiological study.

Abstract: The gross anatomy of the pancreatic blood supply has been subjected to numerous studies. The results of such studies, however, have never been summarized in detail, even in the most important textbooks. For this reason, a certain confusion was generated, especially regarding the interpretation of the nomenclature used to identify pancreatic arteries. This review summarizes more than two centuries of studies of the gross anatomy of the pancreatic blood supply, clarifies the arterial nomenclature, and underlines the aspects about which anatomists are not in agreement. Moreover, it supplies, as far as possible, documentary evidence for numerous observations previously reported only verbally. For this purpose, more than 200 references were directly consulted to provide the anatomical background of the topic, and more than 1000 angiograms were studied to support the review with original figures. The present paper, on the superior pancreaticoduodenal and anterior superior pancreaticoduodenal arteries, is the first of a series of articles dealing with the pancreatic blood supply.