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Biomedical subjects

L Rossi

Publications and source records attributed to L Rossi.

At least 37 records · Page 2Linked to original sources

Dietary habits and nutritional biomarkers in Italian type 1 diabetes families: evidence of unhealthy diet and combined-vitamin-deficient intakes.

OBJECTIVE: Nutritional status and lifestyle can have profound effects on health. To analyse behaviour patterns in population subgroups of public health importance, we compared lifestyle, dietary intake of energy and selected nutrients, and nutritional biomarkers of type 1 diabetes (T1DM) patients and nondiabetic first-degree relatives against control subjects with no family history of T1DM. DESIGN: A cross-sectional study. SETTING: Department of Internal Medicine, University of Pisa, Italy. SUBJECTS: A total of 209 individuals including 38 type 1 patients, 76 relatives, and 95 healthy subjects. INTERVENTIONS: We used the European Prospective Investigation of Cancer and Nutrition questionnaires to assess dietary intake and lifestyle. Anthropometric indices and nutritional biomarkers (such as plasma levels of albumin, iron, lipids, homocysteine, vitamin B9 and vitamin B12 as well as urinary outputs of nitrogen, sodium and potassium) were evaluated. RESULTS: Emerging health issues: (1) In total, 45% of controls were overweight. Increasing age was associated with increasing body mass and decreasing activity in sport in front of an unchanged energy intake. (2) The distribution of energy sources was incorrect. The proportion of caloric intake derived from total fat and cholesterol did not match general guidelines. Total dietary fibre consumption was assessed to be adequate (25 g/day) in only 27% of all the participants. (3) Estimated daily intakes of water-soluble vitamin B9 and fat-soluble vitamin D and vitamin E were deficient in comparison with dietary reference intakes. (4) The prevalence of adoption and maintenance of healthful eating and physical activity habits was higher in women and T1DM patients (probably as a consequence of the medical educational intervention). On the contrary, supportiveness of the family in term of changing the undesirable behaviours at home seemed to fail. CONCLUSIONS: This study provides first evidence indicating unhealthy dietary behaviours, which could even predispose to the development of diabetes and cardiovascular complications, in subjects living in Pisa. The combination of vitamin B9 and vitamin E deprivation could be deleterious for endothelial function, since these antioxidants have been implicated in the modulation of nitric oxide and eicosanoid signalling.

Adult↗

Multiple returns for some regular and mixing maps.

We study the distributions of the number of visits for some noteworthy dynamical systems, considering whether limit laws exist by taking domains that shrink around points of the phase space. It is well known that for highly mixing systems such limit distributions exhibit a Poissonian behavior. We analyze instead a skew integrable map defined on a cylinder that models a shear flow. Since almost all fibers are given by irrational rotations, we at first investigate the distributions of the number of visits for irrational rotations on the circle. In this last case the numerical results strongly suggest the existence of limit laws when the shrinking domain is chosen in a descending chain of renormalization intervals. On the other hand, the numerical analysis performed for the skew map shows that limit distributions exist even if we take domains shrinking in an arbitrary way around a point, and these distributions appear to follow a power law decay of which we propose a theoretical explanation. It is interesting to note that we observe a similar behavior for domains wholly contained in the integrable region of the standard map. We also consider the case of two or more systems coupled together, proving that the distributions of the number of visits for domains intersecting the boundary between different regions are a linear superposition of the distributions characteristic of each region. Using this result we show that the real limit distributions can be hidden by some finite-size effects. In particular, when a chaotic and a regular region are glued together, the limit distributions follow a Poisson-like law, but as long as the measure of the shrinking domain is not zero, the polynomial behavior of the regular component dominates for large times. Such an analysis seems helpful to understand the dynamics in the regions where ergodic and regular motions are intertwined, as it may occur for the standard map. Finally, we study the distributions of the number of visits around generic and periodic points of the dissipative Henon map. Although this map is not uniformly hyperbolic, the distributions computed for generic points show a Poissonian behavior, as usually occurs for systems with highly mixing dynamics, whereas for periodic points the distributions follow a different law that is obtained from the statistics of first return times by assuming that subsequent returns are independent. These results are consistent with a possible rapid decay of the correlations for the Henon map.

Algorithms↗

The acceptability of isoflavones as a treatment of menopausal symptoms: a European survey among postmenopausal women.

OBJECTIVE: To investigate determinants of the acceptability of isoflavone products among postmenopausal women with regard to social and lifestyle factors, dietary habits, health concerns, food beliefs, menopausal symptoms and therapies, and to elucidate preferences for specific products. METHODS: A consumer survey was conducted among postmenopausal women in four European countries (Germany, Denmark, Italy and the UK), including a total of 465 respondents. RESULTS: The declared acceptability of isoflavones was highest in Germany (80%), followed by Italy (75%), the UK (59%) and Denmark (55%; p < 0.001). Among other factors, prior information about isoflavones (odds ratio (OR) 2.64, 95% confidence interval (CI) 1.54-4.51, p < 0.001) and belief that foods can be used to treat medical conditions (OR 2.18, 95% CI 1.17-4.05, p = 0.014) were the strongest predictors of potential acceptability. The preferred forms in which isoflavones might be taken differed markedly between countries. CONCLUSIONS: Information about the health effects of isoflavones and health-diet links should be considered the most important factors in attempts to influence the potential acceptability of isoflavone products. Foods enriched with isoflavones need to be developed with regard to specific cultural demands in order to assure consumer acceptance on the marketplace.

Age Factors↗

Effect of morphine on cell-mediated immune responses of human lymphocytes against allogeneic malignant cells.

Opioid drugs, including morphine, are largely used as pain control in cancer patients at different stages of neoplastic growth and progression. Therefore, the possible influence of these drugs on host immunity appears to be of considerable interest. We have examined in vitro the effect of morphine on the generation of human cytotoxic T lymphocytes (CTL) against HTLV-I induced T-cell leukemia cells (MT-2 line). The results show that the drug, at graded concentrations (from 3 pg/ml to 32 microg/ml), that include those detectable in treated patients, enhances CTL activity whereas natural killer cell activity was unaffected. The enhancing effect is particularly evident when morphine was present at the onset of lymphocyte/MT-2 co-culture. On the contrary, the drug was ineffective when added on the last day of co-culture, thus indicating that morphine operates during the generation phase of CTL, but not on mature CTL. Flow cytometric analysis of intracellular cytokine expression showed that morphine increases the percentage of interferon gamma-producing CD8+ T cells in co-culture assay. Collectively, these results suggest that in our experimental model morphine enhances CTL responses by directly affecting the induction phase of T-dependent cell-mediated immunity.

Analgesics, Opioid↗

Diabetes mellitus in Tropical Chronic Pancreatitis Is Not Just a Secondary Type of Diabetes.

AIMS: In chronic calcific pancreatitis of the tropics, etiology and relationship to developing diabetes mellitus are unknown. Some consider these cases a straightforward secondary type of diabetes, while others suggest selective beta-cell impairment. Testing pancreatic function, we investigated whether selective beta-cell impairment triggers diabetes associated with tropical pancreatitis. METHODS: At a Bangladeshi research institute, 8 chronic tropical pancreatitis and no diabetes mellitus subjects, 14 fibrocalculous pancreatic diabetics and 27 matched healthy controls underwent arginine (endocrine pancreatic function) and secretin (exocrine pancreatic function assessment) stimulation tests. RESULTS: All patients with clinically-diagnosed, chronic pancreatitis demonstrated pronounced exocrine pancreatic dysfunction with beta-cell functioning differing significantly between the two groups. Compared to controls, patients having tropical pancreatitis and no diabetes showed normal plasma C-peptide values at baseline and after arginine stimulation, while fibrocalculous pancreatic diabetics demonstrated a typical diabetic pattern for plasma C-peptide levels. In contrast, pancreatic alpha-cell functioning (glucagon response to arginine) was preserved in both pancreatitis groups. CONCLUSION: A preserved pancreatic alpha-cell function in diabetics with advanced chronic pancreatitis of the tropics supports the concept of two different pathogenic mechanisms, one eliciting chronic pancreatitis and the other selective pancreatic beta-cell impairment and subsequent diabetes mellitus.

Adult↗

Effect of listeriolysin O-loaded erythrocytes on Mycobacterium avium replication within macrophages.

OBJECTIVE: To evaluate the efficacy of erythrocytes loaded with the haemolytic toxin listeriolysin O against Mycobacterium avium replication within human macrophages. METHODS: Recombinant listeriolysin O was loaded in human erythrocytes by a procedure of hypotonic dialysis and isotonic resealing. Loaded erythrocytes were modified to allow them to be recognized and taken up by human macrophages infected with M. avium. The antimycobacterial activity of the erythrocytes loaded with listeriolysin O was evaluated by supernatant and intracellular cfu counts on days 4 and 7 post-erythrocyte administration. RESULTS: Recombinant listeriolysin O was encapsulated in human erythrocytes to reach final concentrations ranging from 1 to 4 ng/mL of erythrocytes. Erythrocytes loaded with increasing quantities of recombinant protein were able to reduce (at most by 50%) M. avium replication in a dose-dependent fashion when administered to infected macrophages. CONCLUSIONS: Erythrocytes loaded with listeriolysin O are effective against M. avium replication within macrophages. We are confident that the strategy presented could be useful against mycobacteria other than M. avium (such as Mycobacterium tuberculosis and Mycobacterium leprae) by itself or as part of an antimycobacterial treatment.

Bacterial Toxins↗

Experience with laparoscopic adrenalectomy in children.

PURPOSE: The aim of this study was to review the authors' experience with laparoscopic adrenalectomy in the pediatric age group. METHODS: This is a retrospective analysis of laparoscopic adrenalectomies performed in children at King Faisal Specialist Hospital & Research Centre, between June 1997 and March 2003. Ten children had laparoscopic adrenalectomies during this period. They were between 3 weeks to 12 years of age and there was an equal number of boys and girls. Case selection was based mainly on the size of the lesion and its localized nature as seen on the imaging studies. The transperitoneal approach was used in all cases. RESULTS: Eleven laparoscopic adrenalectomies were performed in 10 children (1 was bilateral adrenalectomy). Presenting features were virilization (n = 3), Cushing's syndrome (n = 1), antenatally detected adrenal cyst (n = 1), hypertension (n = 1), hepatomegaly (n = 1), loin pain with hematuria (n = 1) and an incidental adrenal mass (n = 1). One was a child with stage IV adrenal neuroblastoma postchemotherapy for resection of the residual tumor. On imaging studies, the tumors were between 2.8 and 7 cm in their largest dimension. Operating time ranged from 118 to 180 minutes in the unilateral resections, whereas the bilateral laparoscopic adrenalectomy required 330 minutes. Two had to be converted to open procedures. Postoperative hospital stay was between 2 and 15 days. Pathologic diagnoses were as follows: adrenal cortical adenoma (n = 3), adrenal medullary hyperplasia (n = 2), adrenal cortical carcinoma (n = 1), ganglioneuroma (n = 1), and neuroblastoma (n = 3). There were no complications. Follow-up ranged from 3 months to 6 years. The only mortality in our study group was in the child with stage IV neuroblastoma who died of disseminated disease 9 months later. In the rest, there has been no local recurrence or metastases, and the biochemical and hormonal parameters have remained normal in the functional tumors. CONCLUSIONS: We believe that in a select group of pediatric adrenal lesions, laparoscopic adrenalectomy is a safe and effective procedure with the potential benefits of minimally invasive procedures.

Adrenal Gland Diseases↗

Albumin-containing sol-gel glasses: chemical and biological study.

Glasses incorporating increasing amounts of bovine serum albumin were prepared by sol-gel techniques from a tetra methoxy silane precursor. The surface of the glass samples was studied by X-ray photoelectron spectroscopy, revealing that the protein is present also in the superficial layer of the silica network. Moreover, the protein is distributed in a dose-dependent way, since the N/Si atomic ratio increases linearly with the albumin concentration in the reaction mixture. Angle-dependent measurements show that the protein distribution occurs homogeneously and is the same at different sampling depths. Protein incorporation in the bulk SiO2 network, with a uniform protein distribution between bulk and surface, is confirmed by infrared spectroscopy measurements, performed both in reflectance and transmittance mode. The reaction with a specific antibody and the adhesivity assay of osteoblastic cells show that embedded albumin present on the glass surface is able to interact with other proteins.

Adsorption↗

Statistics of Poincaré recurrences for maps with integrable and ergodic components.

Recurrence gives powerful tools to investigate the statistical properties of dynamical systems. We present in this paper some applications of the statistics of first return times to characterize the mixed behavior of dynamical systems in which chaotic and regular motion coexist. Our analysis is local: we take a neighborhood A of a point x and consider the conditional distribution of the points leaving A and for which the first return to A, suitably normalized, is bigger than t. When the measure of A shrinks to zero the distribution converges to the exponential e(-t) for almost any point x, if the system is mixing and the set A is a ball or a cylinder. We consider instead a system, a skew integrable map of the cylinder, which is not ergodic and has zero entropy. This map describes a shear flow and has a local mixing property. We rigorously prove that the statistics of first return is of polynomial type around the fixed points and we generalize around other points with numerical computations. The result could be extended to quasi-integrable area preserving maps such as the standard map for small coupling. We then analyze the distribution of return times in a region which is composed by two invariants subdomains: one with a mixing dynamics and the other with an integrable dynamics given by our shear flow. We show that the statistics of first return in this mixed region is asymptotically given by the exponential law, but this limit is attained by an intermediate regime where exponential and polynomial laws are linearly superposed and weighted by some factors which are proportional to the relative sizes of the chaotic and regular regions. The result on the statistics of first return times for mixed regions in the phase space can provide a basis to analyze such a property for area preserving maps in mixed regions even when a rigorous result is not available. To this end we present numerical investigations on the standard map which confirm the results of the model.

Algorithms↗

Cytokine gene expression and production by human LPS-stimulated mononuclear cells are inhibited by sulfated heparin-like semi-synthetic derivatives.

BACKGROUND: The K5 polysaccharide obtained from Escherichia coli strain 010:K5:H4 is a polymer of the disaccharidic unit formed by D-glucuronic acid and N-acetylglucosamine. This structure is akin to N-acetylheparosan, the precursory polymer of heparin and of heparan sulfate. This structural affinity with N-acetylated heparin and with de-sulfated heparin makes the K5 polysaccharide extremely useful for the preparation of sulfated heparin-like semi-synthetic derivatives. It has been demonstrated that heparins are able to inhibit tissue factor and cytokine production and expression by human monocytes. OBJECTIVE: The aim of this study was to evaluate the effects of four different heparin-like semi-synthetic derivatives on inflammatory cytokine production and expression by human mononuclear cells. RESULTS: The simultaneous addition of lipopolysaccharide (LPS; 0.2 and 10 micro g mL(-1)) and the K5 polysaccharide did not inhibit interleukin (IL)-1beta, IL-6 or tumor necrosis factor (TNF)-alpha production by stimulated mononuclear cells. IL-1beta, IL-6 and TNF-alpha concentrations in supernatants of LPS-stimulated mononuclear cells were not influenced by the addition of N,O-sulfated K5 polysaccharide (K5-N, OS) and epimerized N-sulfated K5 polysaccharide (K5 NS epi) at 5 and 10 microg mL(-1), whereas the addition of epimerized N,O-sulfated K5 polysaccharide (K5-N, OS epi) (5 and 10 microg mL(-1)) and O-sulfated K5 polysaccharide (K5-OS) (5 and 10 microg mL(-1)) to LPS-stimulated cells caused a significant dose-dependent inhibition of IL-1beta, IL-6 and TNF-alpha. All sulfated heparin-like semi-synthetic derivatives did not influence the IL-10 production by LPS-stimulated mononuclear cells. In LPS-stimulated cells (0.2 and 10 microg mL(-1)), K5-OS or K5-N, OS epi at 5 and 10 microg mL(-1) markedly decreased TNF-alpha mRNA expression. CONCLUSIONS: These results indicate that the sulfated heparin-like semi-synthetic derivatives K5-OS and K5-N, OS epi are able to inhibit both expression and production of inflammatory cytokines, whereas they do not influence the anti-inflammatory cytokine IL-10, suggesting a potential role for these products as modulators of inflammatory reactions.

Bacterial Capsules↗

[Monitoring of canine leishmaniasis in northern Italy: an update from a scientific network].

Canine leishmaniasis (CanL) due to Leishmania infantum is a disease of great veterinary importance and a serious public health problem. In humans, L. infantum causes visceral (VL) and cutaneous leishmaniasis (CL) and the distribution of VL overlaps that of CanL. Currently, VL is considered by WHO as an emerging zoonosis in southern Europe. The dog is the only domestic reservoir of the infection and phlebotomine sandflies are the only proven vectors of leishmaniasis for dogs and humans. CanL is endemic in Italy, particularly in central and southern regions, including islands. Until 1983, all regions of northern Italy but Liguria and some territories of Emilia Romagna were considered free from CanL. From early '90s new stable foci of CanL have appeared, most of them located within classical endemic areas including territories of Emilia Romagna, Tuscany, Umbria, Marche, and Abruzzi regions. But the most relevant aspect, from an epidemiological point of view, has been the appearance of stable CanL foci in northern Italy, namely in Veneto and Piedmont regions. In these two foci, entomological surveys showed the presence of P. perniciosus and of a second phlebotomine vector, P. neglectus, which may have played a role in the CanL diffusion in some parts of northern Italy. Furthermore, in these areas, autochthonous human VL cases have occurred. There is therefore a realistic risk that CanL infection could rapidly spread through northern latitudes and a surveillance activity is strongly needed. For this reason, in October 2002, thanks to the collaboration and support of Intervet Italia, the network "LeishMap" was created, with the main purpose of monitoring the spread of CanL and vectors in northern Italy. LeishMap consists of scientific and sanitary institutions with proven experience both in field surveys and diagnostic methodologies on CanL and phlebotomine vector. It is organised in 4 Operational Units (OU), represented by researchers of the Veterinary Faculties of the University of Bologna, Padua, Milan and Turin, under the scientific coordination of the MIPI Department, ISS of Rome and with the collaboration of private and public veterinarians operating in the regions under study. During the first year of activity, each OU was involved in the serological and entomological surveillance of several territories in the respective regions, where recent autochthonous CanL cases were registered. The studies have involved five regions, namely Valle D'Aosta, Piedmont, Lombardia, Veneto, Trentino-Alto Adige and Emilia Romagna. In the Symposium 6 of this Congress we report detailed results of a retrospective analysis of data concerning CanL and vectors in northern Italy till 2002 and the preliminary results of 2003 on the seroprevalence rates observed in foci studied and on the entomological surveys carried out. In summary, the results outlined that already known foci of CanL are expanding from the original sites. Several new foci have been identified and many others are at high risk of evolving toward a stable endemicity. P. perniciosus has been found in all but one the suspected new foci. In Emilia Romagna region P. perfiliewi was identified in 2 areas and in one was the only species present. The occurrence of P. neglectus was confirmed in three regions, Veneto, Lombardia and Piedmont. In conclusion, from the 2002-2003 LeishMap activities it appears that further monitoring activities are necessary to identify new endemic foci of CanL, this representing the prerequisite for the implementation of programs for leishmaniasis control in northern Italy.

Animals↗

Prolonged copper depletion induces expression of antioxidants and triggers apoptosis in SH-SY5Y neuroblastoma cells.

SH-SY5Y neuroblastoma cells were cultured for up to three serial passages in the presence of the copper chelator triethylene tetramine (Trien). The copper-depleted neuroblastoma cell line obtained showed decreased activities of the copper enzymes Cu, Zn super-oxide dismutase and cytochrome c oxidase with concomitant increases in reactive oxygen species. Mitochondrial antioxidants (Mn superoxide dismutase and Bcl-2)were up-regulated. Overexpression and activation of p53 were early responses, leading to an increase in p21. Eventually, copper-depleted cells detached from the monolayer and underwent apoptosis. Activation of upstream caspase-9, but not caspase-8, suggested that apoptosis proceeds via a mitochondrial pathway, followed by caspase-3 activation. The addition of copper sulfate to the copper-depleted cells restored copper enzymes, normalized antioxidant levels and improved cell viability. We conclude that prolonged copper starvation in these replicating cells leads to mitochondrial damage and oxidative stress and ultimately, apoptosis.

Antioxidants↗

Suprathreshold 0.3 Hz repetitive TMS prolongs the cortical silent period: potential implications for therapeutic trials in epilepsy.

OBJECTIVE: To investigate the after-effects of 0.3 Hz repetitive transcranial magnetic stimulation (rTMS) on excitatory and inhibitory mechanisms at the primary motor cortex level, as tested by single-pulse TMS variables. METHODS: In 9 healthy subjects, we studied a wide set of neurophysiological and behavioral variables from the first dorsal interosseous before (Baseline), immediately after (Post 1), and 90 min after (Post 2) the end of a 30 min long train of 0.3 Hz rTMS delivered at an intensity of 115% resting motor threshold (RMT). Variables under investigation were: maximal M wave, F wave, and peripheral silent period after ulnar nerve stimulation; RMT, amplitude and stimulus-response curve of the motor evoked potential (MEP), and cortical silent period (CSP) following TMS; finger-tapping speed. RESULTS: The CSP was consistently lengthened at both Post 1 and Post 2 compared with Baseline. The other variables did not change significantly. CONCLUSIONS: These findings suggest that suprathreshold 0.3 Hz rTMS produces a relatively long-lasting enhancement of the inhibitory mechanisms responsible for the CSP. These effects differ from those, previously reported, of 0.9-1 Hz rTMS, which reduces the excitability of the circuits underlying the MEP and does not affect the CSP. This provides rationale for sham-controlled trials aiming to assess the therapeutic potential of 0.3 Hz rTMS in epilepsy.

Adult↗