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A Spano

Publications and source records attributed to A Spano.

At least 19 recordsLinked to original sources
PubMed2001

Polymorphisms in the promoter region and at codon 54 of the MBL2 gene are not associated with IgA nephropathy.

BACKGROUND: IgA nephropathy (IgAN) occurs sporadically in unrelated individuals. Several different polymorphic genes have been investigated in recent years in order to demonstrate their possible association with IgAN. Three recent, different studies with conflicting conclusions have discussed the role of the mannose binding lectin (MBL), a serum lectin involved in natural immunity, in the IgAN pathogenesis by examination of MBL deposits in biopsies. In the present study we investigated several polymorphisms of the MBL gene located in the promoter region and in the first exon. METHODS: MBL polymorphism detection was performed in 22 Italian patients with familial IgA nephropathy and in 138 Italian patients with the sporadic form of the disease. The polymorphisms in the MBL2 promoter region and in the exon 1 were investigated, respectively, by direct sequencing and by amplification refractory mutation system-polymerase chain reaction on genomic DNA collected from peripheral blood. Seventy-four unrelated healthy subjects matched for ethnic origin were used as controls. RESULTS: Allelic and genotypic frequencies of the polymorphisms at position -550, -328, -221 and at codon 54 did not show any differences between patients and controls. Similar frequency distributions of these polymorphisms were also found in the subgroups of IgAN patients subdivided according to the clinical manifestations and the progression of the disease. CONCLUSIONS: This study indicates that the analysed polymorphisms of the MBL gene do not appear to be primarily involved in the susceptibility and severity of IgAN.

Adolescent↗
PubMed2001

Aberrant localization of the neuronal class III beta-tubulin in astrocytomas.

BACKGROUND: The class III beta-tubulin isotype (betaIII) is widely regarded as a neuronal marker in development and neoplasia. In previous work, we have shown that the expression of betaIII in neuronal/neuroblastic tumors is differentiation dependent. In contrast, the aberrant localization of this isotype in certain nonneuronal neoplasms, such as epithelial neuroendocrine lung tumors, is associated with anaplastic potential. OBJECTIVE: To test the generality of this observation, we investigated the immunoreactivity profile of betaIII in astrocytomas. DESIGN: Sixty archival, surgically excised astrocytomas (8 pilocytic astrocytomas, WHO grade 1; 18 diffuse fibrillary astrocytomas, WHO grade 2; 4 anaplastic astrocytomas, WHO grade 3; and 30 glioblastomas, WHO grade 4), were studied by immunohistochemistry using anti-betaIII monoclonal (TuJ1) and polyclonal antibodies. A monoclonal antibody to Ki-67 nuclear antigen (NC-MM1) was used as a marker for cell proliferation. Antibodies to glial fibrillary acidic protein (GFAP) and BM89 synaptic vesicle antigen/synaptophysin were used as glial and neuronal markers, respectively. RESULTS: The betaIII immunoreactivity was significantly greater in high-grade astrocytomas (anaplastic astrocytomas and glioblastomas; median labeling index [MLI], 35%; interquartile range [IQR], 20%-47%) as compared with diffuse fibrillary astrocytomas (MLI, 4%; IQR, 0.2%-21%) (P <.0001) and was rarely detectable in pilocytic astrocytomas (MLI, 0%; IQR, 0%-0.5%) (P <.0001 vs high-grade astrocytomas; P <.01 vs diffuse fibrillary astrocytomas). A highly significant, grade-dependent relationship was observed between betaIII and Ki-67 labeling and malignancy, but this association was stronger for Ki-67 than for betaIII (betaIII, P <.006; Ki-67, P <.0001). There was co-localization of betaIII and GFAP in neoplastic astrocytes, but no BM89 synaptic vesicle antigen/synaptophysin staining was detected. CONCLUSIONS: In the context of astrocytic gliomas, betaIII immunoreactivity is associated with an ascending gradient of malignancy and thus may be a useful ancillary diagnostic marker. However, the significance of betaIII-positive phenotypes in diffuse fibrillary astrocytomas with respect to prognostic and predictive value requires further evaluation. Under certain neoplastic conditions, betaIII expression is not neuron specific, calling for a cautious interpretation of betaIII-positive phenotypes in brain tumors.

Adolescent↗
PubMed2001

Direct in situ PCR allows rapid and sensitive detection of high risk human papillomavirus in cytologic specimens and formalin-fixed paraffin tissues by fluorescent labelling.

We developed a rapid, sensitive and robust high risk human papillomavirus (HR HPV) detection protocol based on direct in situ PCR technology and fluorochrome-modified nucleotides on cytologic specimens (cell smears) and on HPV infected tissues (CIN III). Reproducible results on both cytologic specimens and paraffin-embedded tissues were obtained, providing a powerful tool for clinical investigation on HR HPV infection. Quantitative PCR performed on the same tissue sections adjacent to those used for in situ techniques allowed us to establish the sensitivity of our methods, able to detect rare copies (about 15 in our paraffin-embedded tissues) of HPV.

Female↗
PubMed2000

Relationship between actin microfilaments and plasma membrane changes during apoptosis of neoplastic cell lines in different culture conditions.

In this study we investigated the relationship between the reorganisation of actin cytoskeleton and the changes at cell surface level (i.e. PS exposure and blebbing) in two neoplastic cell lines during apoptosis: Chang liver cells (adherent culture) and promyelocytic HL-60 cells (suspension culture), treated with the podophyllotoxin derivative VP16. The morphological analysis, performed by means of conventional fluorescence microscopy and confocal laser scanning microscopy, on Chang cells showed that onset and progress of the two processes are synchronised. The initial disassembly of stress fibers was associated with the early PS exposure on the cell surface. Moreover, the accumulation of actin at cortical level appeared strongly associated with an intense labelling for Annexin V and, in some cases, especially in the areas of membrane blebbing. The double staining for actin and PS exposure, quantitatively analysed by flow cytometry in HL-60 cells after different treatment times, demonstrated that the decrease of Annexin V binding in the late stages of apoptosis is associated with the strong reduction of actin labelling probably also due to a proteolytic cleavage. These events were also partially related to variations of the functional state of mitochondria, by analysing cytofluorometrically the dissipation of the inner membrane potential (delta psi m).

Actin Cytoskeleton↗
PubMed2000

Cytoskeleton actin changes in IL-2 activated cells.

In the present study we analysed the changes in cytoskeleton actin in lymphoid cells following IL-2 activation and during cell interactions by means of light and electron microscopy, immunofluorescence and molecular analysis. By morphological analysis we observed a higher fluorescence in the activated cells than in the quiescent ones with no modifications in the cytoskeleton pattern comparing activated to resting cells. The results of molecular analysis indicate that, after IL-2 activation, there is a reorganisation of the actin component of the cell cytoskeleton accompanied by the differential expression of the corresponding genes. A future study will be extended to the analysis of others components of the cytoskeleton network.

Actins↗
PubMed1999

Influence of microgravity on mitogen binding and cytoskeleton in Jurkat cells.

The effects of microgravity on Jurkat cells--a T-lymphoid cell line--was studied on a sounding rocket flight. An automated pre-programmed instrument permitted the injection of fluorescent labelled concanavalin A (Con A), culture medium and/or fixative at given times. An in-flight 1 g centrifuge allowed the comparison of the data obtained in microgravity with a 1 g control having the same history related to launch and re-entry. After flight, the cells fixed either at the onset of microgravity or after a or 12 minute incubation time with fluorescent concanavalin A were labelled for vimentin and actin and analysed by fluorescence microscopy. Binding of Con A to Jurkat cells is not influenced by microgravity, whereas patching of the Con A receptors is significantly lower. A significant higher number of cells show changes in the structure of vimentin in microgravity. Most evident is the appearance of large bundles, significantly increased in the microgravity samples. No changes are found in the structure of actin and in the colocalisation of actin on the inner side of the cell membrane with the Con A receptors after binding of the mitogen.

Actins↗
PubMed1999

Dependence of fibroblast autofluorescence properties on normal and transformed conditions. Role of the metabolic activity.

The dependence of autofluorescence properties on the metabolic and functional engagement and on the transformation condition was studied on single cells. Normal Galliera rat fibroblasts at low subculture passage (cell strain), at high subculture passage (stabilized cell line), and transformed cell line derived from a rat sarcoma were used as a cell model. The study was performed by microspectrofluorometric and fluorescence imaging technique. The autofluorescence properties of cells were studied by excitation at two wavelengths, namely 366 nm and 436 nm, that are known to favor the emission of different fluorophores. Spectral shape analysis indicated that under excitation at 366 nm autofluorescence is ascribable mainly to coenzyme molecules, particularly to reduced pyridine nucleotides, while under excitation at 436 nm, flavin and lipopigment emission is favored. The energetic metabolic engagement of the different cell lines was analyzed in terms both of parameters related to anaerobic-aerobic pathways (biochemical assay) and of mitochondrial features (supravital cytometry). The results showed that the cell strain and the stabilized and transformed cell lines can be distinguished from one another on the basis of both overall fluorescence intensity and the relative contributions of spectral components. These findings indicated a relationship between autofluorescence properties and energetic metabolism engagement of the cells that, in turn, is dependent on the proliferative activity and the transformed condition of the cells. In that it is a direct expression of the energetic metabolic engagement, autofluorescence can be assumed as an intrinsic parameter of the cell biological condition, suitable for diagnostic purposes.

Animals↗
PubMed1996

Movements and interactions of leukocytes in microgravity.

The mitogenic activation of human lymphocytes resuspended in vitro is dramatically reduced in microgravity. As cell-cell contacts are one of the elements essential for activation, the behaviour of human leukocytes (mainly lymphocytes and monocytes as accessory cells) in the presence of the mitogen concanavalin A was studied in the centrifuge microscope NIZEMI at 0 x g. Aggregates (formed by intercellular bindings of membrane glycoproteins via the tetravalent alpha-glucoside ligand concanavalin A) were found at 0 x g as well as at 1 x g already 12 h after the addition of the mitogen. In general, the aggregates observed at 0 x g after an incubation time of 46 and 78 h were smaller than the corresponding aggregates in the ground control. The findings are of primary importance since they confirm the indirect evidence we had from earlier Spacelab experiments and demonstrate that cell-cell contacts are occurring also in microgravity. In addition, single cells in 0 x g show a significant higher locomotion velocity than the cells at 1 x g. The fact that the locomotion capability is not decreased during the 78-h incubation with concanavalin A provides further evidence that the cells are not proceeding through the cell cycle.

Biotechnology↗
PubMed1996

Activation signals of T lymphocytes in microgravity.

Human peripheral blood lymphocytes and monocytes were activated with concanavalin A with or without exogenous recombinant interleukin 1 (IL-1) alone or IL-1 + interleukin 2 (IL-2) under microgravity conditions to test the hypothesis that lack of production of IL-1 by monocytes is the cause of the near total loss of activation observed earlier on several Spacelab flights. The 60 min failure of the on-board 1 x g reference centrifuge at the time of the addition of the activator renders the in-flight data at 1 x g unreliable. However, the data from a previous experiment on SLS-1 show that there is no difference between the results from the in-flight 1 x g centrifuge and 1 x g on ground. The comparison between the data of the cultures at 0 x g in space and of the synchronous control at 1 x g on ground show that exogenous IL-1 and IL-2 do not prevent the loss of activity (measured as the mitotic index) at 0 x g; production of interferon-gamma, however, is partially restored. In contrast to a previous experiment in space, the production of IL-1 is not inhibited.

Biotechnology↗
PubMed1996

Static cytofluorometry and fluorescence morphology of mitochondria and DNA in proliferating fibroblasts.

The shape, distribution, and content of mitochondria in individual cells were examined during the cell cycle phases (G(0)/G(1), S, G(2) mitosis) in living human fibroblasts by static cytofluorometry and fluorescence microscopy. The morphocytochemical evaluations were performed in cell cultures submitted to double supravital fluorochrome staining with Hoechst 33342 and DiOC(6) to label DNA and mitochondria, respectively. The staining modalities were based on the stability of mitochondrial labeling. The G(1) to early S phases were characterized by the presence of filamentous mitochondria, except during the early postmitotic period. During late S, G(2), and mitotic phases, mitochondrial mass reached its highest value and mitochondria became short and numerous. During the last stage of mitosis, mitochondria were distributed among daughter cells through a cytoplasmic bridge.

Benzimidazoles↗
PubMed1994

Use of pooled residual laboratory sera to assess human immunodeficiency virus prevalence among patients in Italy. The Italian Study Group on Occupational Risk of HIV infection.

An anonymous unlinked seroprevalence study of human immunodeficiency virus (HIV) infection was performed by testing pools of ten sera remaining from specimens submitted consecutively to clinical pathology laboratories at 18 Italian public hospitals during four consecutive days in April 1991. Sera from positive pools were retested individually by three different enzyme immunoassays (EIAs) and considered positive if reactive by all three assays. Only the sera with discordant EIA results were retested by Western blot. Of a total of 22,590 sera, 278 were HIV positive (1.2%). The highest rates were seen in hospitals located in metropolitan areas (1.5%), in infectious disease departments (28%) and in drug addiction treatment units (28%); among men aged 21-30 (4.6%) and 31-40 years (4%); and among women aged 21-30 years (1.6%). The distribution of seropositive patients by gender and age group suggests an increasing role of heterosexual transmissions of the infection. The presence of anti-HIV antibodies in sera from patients of both sexes, in all age groups, and from all clinical settings reinforces the need for health care workers to adhere to universal precautions issued to prevent occupational bloodborne infections.

Adolescent↗
PubMed1993

[Various nuclear and cytoplasmic parameters in relation to the evolution of an in vitro culture of rat fibroblasts].

A cytokinetic study was performed on progressive subcultures of a cellular strain represented by fibroblasts (FG: Fibroblasts Galliera). Our previous studies on these cells showed morphofunctional changes in relation to cell ageing, indicating the stabilization of a cell line with high proliferative capacity. Furthermore, in the present work, we carried out a comparative analysis with a neoplastic strain (SGS/3A cells), characterized by a low state of cell differentiation. The morphological (fluorescence microscopy) and quantitative (flow cytometry) analysis, examined the relative DNA/protein and DNA/RNA ratios. Moreover, the replicative and mitotic activity and the apoptotic degeneration was determined. The results obtained indicated the existence in this biological model of a different relation between cell growth and cell proliferation. The analysis of our results allowed us to hypothesize that the cellular subpopulation selected during the culture progression of FG cells constitutes a cell line highly able of survival in vitro. In these cells the high proliferative activity is opposite to a reduced metabolism.

Animals↗
PubMed1991

[Estrogen receptor levels in the liver of intact and gonadectomized rats and in cultured hepatocytes].

The concentrations of hepatic estrogen receptor were determined in intact and gonadectomized male and female rats. The hydroxylapatite assay demonstrated that the ablation of gonads induces, in the liver, an increase of estrogen receptors. The data obtained suggests that the synthesis of these receptors in the liver might be estrogen- and androgen-dependent. The same analysis performed on hepatocyte cytosol, derived from ovariectomized females, and cultured for 24, 48 and 72 hours, showed that time of culture is an important factor in determining a decrease of estrogen receptor concentrations in the cells. The results obtained allowed us to conclude that in the maintenance of the normal levels of the hepatic estrogen receptors, either sexual and non-sexual hormones are involved.

Animals↗
PubMed1991

[Peptidase activity and toxicity of strains of Pseudomonas aeruginosa].

Pseudomonas aeruginosa is a microorganism of the terrestrial and aquatic environment which may cause pulmonary, urinary and corneal infections. The pathogenesis of Pseudomonas-induced diseases seems to be linked to the production of extracellular substances such as exotoxins, hemolysins, leukocidins and hydrolytic enzymes, including various peptidases. Anyway there is not a clear view on the role other proteases have in the mechanism of pathogenesis, and even if their activity may always be associated to the toxicity of the microorganism. We have therefore determined the activity of a number of eso- and endopeptidases in 17 strains of P. aeruginosa isolated from patients with urinary pathologies. Four of these peptidase activities, namely elastase, neutral protease, aminopeptidase I and leucine aminopeptidase show a positive correlation with three parameters selected as indices of toxicity, i.e. the mucoid appearance, the gentamicin resistance and the adhesivity of colonies.

Aminopeptidases↗
PubMed1989

[Dietary habits of school children: breakfast].

An investigation on the dietary habits of 944 secondary school children from Alghero, with reference to breakfast consumption and composition, has shown that the percentage of students who eat nothing for breakfast is higher than that reported by other authors. Furthermore it has been noted that consumption decreases among grown up students. Milk and coffee is the most common type of nutriment and also bread and biscuits are well represented. Other types of food, such as jam, yogurt or butter, are instead rarely consumed. Therefore the average caloric intake is of about 400 Kcal.

Adolescent↗
PubMedDate not supplied

[An anthropometric study of Sassari population 3 to 36 months of age: females].

The average values (+ SD) for height and weight and head circumference of 666 females 3 and 36 months of ages from the city of Sassari (Sardinia) have been determined. Numerical values and smooth curves from the 3rd to the 97th percentile for height and weight and head-circumference have also been calculated. The results were compared with those published by E. De Toni et Al. 20 years ago. The data show a significant increase in height and weight among Sardinian children during the past 20 years. The availability of these new curves will permit a more correct evaluation of growth in Sardinian children.

Age Factors↗
PubMedDate not supplied

[An anthropometric study of the population of Sassari from 3 to 36 months old: males].

The average values (+/- SD) for height and weight and head circumference of 745 males 3 and 36 months of ages from the city of Sassari (Sardinia) have been determined. Numerical values and smooth curves from the 3rd to the 97th percentile for height and weight and head-circumference have also been calculated. The results were compared with those published by E. De Toni ed al. 20 years ago. The data show a significant increase in height and weight among sardinian children during the past 20 years. The availability of these new curves will permit a more correct evaluation of growth in Sardinian children.

Anthropometry↗