Biomedical subjects

M Pugliese

Publications and source records attributed to M Pugliese.

At least 37 records · Page 2Linked to original sources

PubMed2000

Inactivation of human normal and tumour cells irradiated with low energy protons.

PURPOSE: To analyse the cell inactivation frequencies induced by low energy protons in human cells with different sensitivity to photon radiation. MATERIALS AND METHODS: Four human cell lines with various sensitivities to photon irradiation were used: the SCC25 and SQ20B derived from human epithelium tumours of the tongue and larynx, respectively, and the normal lines M/10, derived from human mammary epithelium, and HF19 derived from a lung fibroblast. The cells were irradiated with y-rays and proton beams with linear energy transfer (LET) from 7 to 33 keV/microm. Clonogenic survival was assessed. RESULTS: Survival curves are reported for each cell line following irradiation with gamma-rays and with various proton LETs. The surviving fraction after 2 Gy of gamma-rays was 0.72 for SQ20B cells, and 0.28-0.35 for the other cell lines. The maximum LET proton effectiveness was generally greater than that of gamma-rays. In particular there was a marked increase in beam effectiveness with increasing LET for the most resistant cells (SQ20B) whose 2 Gy-survival varied from 0.72 with gamma-radiation down to 0.37 with 30 keV/microm protons. The relative biological effectiveness (RBE(2 Gy gamma)) with the 30 keV/microm beam, evaluated as the ratio of 2 Gy to the proton dose producing the same inactivation level as that given by 2 Gy of gamma-rays, was 3.2, 1.8, 1.3 and 0.8 for SQ20B, M/10, SCC25, and HF19, respectively. CONCLUSIONS: RBE for inactivation with high-LET protons increased with the cellular radioresistance to gamma-rays. The cell line with the greatest resistance to gamma-rays was the most responsive to the highest LET proton beam. A similar trend has also been found in studies reported in the literature with He, C, N ions with LET in the range 20-125 keV/microm on human tumour cell lines.

Cell Line↗

PubMed2000

[Harmonic echocardiography of tissue in the diagnosis of aneurysms of the interatrial septum. Study of 550 consecutive ambulatory patients].

BACKGROUND: It has been assessed whether echocardiographic harmonic imaging improves the detection of atrial septal aneurysm (ASA) compared with fundamental imaging. METHODS: We studied consecutively, using fundamental and harmonic imaging, 550 patients (with or without cardiopathy; 300 females and 250 males) in an outpatients' department (age 23-76 years, mean 50 years). We used a multifrequency transthoracic probe transmitting at 2 Mhz and receiving at 4 Mhz. The ASA was classified in three types according to Hanley et al. Type 1A, protruding into the right atrium without oscillation; Type 1B protruding into the right atrium with oscillation, and Type 2, protruding into the left atrium with oscillation. We compared atrial septal aneurysm definition in fundamental and harmonic mode, and assessed the interobserver agreement in the diagnosis of ASA. The echocardiographic images were recorded on magneto-optical disk and analysed by two blinded observer. With Pearson test we assessed the interobserver concordance in the ASA study; so we quantified the advantage of harmonic imaging as reduction of the inter-observer variability. RESULTS: Among 550 consecutive subjects in the echocardiographic study population, ASA was diagnosed in 8 (1.45%) and 15 (2.72%) patients using fundamental and harmonic methods respectively. A significant reduction of the inter-observer variability in the ASA diagnosis was found with harmonic imaging (harmonic imaging: r = 0.96; fundamental imaging: r = 0.70). CONCLUSIONS: The harmonic methods drastically improves echocardiographic imaging of ASA, it may be used routinely and reduces the need for more invasive technique such as transesophageal echocardiography.

Adult↗

PubMed2000

[Psychosocial intervention model of neonatal intensive care in Modena].

Many authors agree that psychosocial factors influence the psychophysical development of the infant. These factors must be taken into account in the neonatal care. At the neonatal intensive care unit (NICU) of the University Hospital of Modena, physicians, psychologist and nurses cooperate to take care of each newborn with a difficult psychosocial background. Together they individuate and select newborns with psychosocial difficulties, plan an integrated action and, eventually, address the family to the community services. We describe our experience with 106 cases from 1996 to 1999. The integrated action included observation of parental behavior within the NICU and psychological support for parents by means of psychological counselling. Many meetings among physicians, nurses, psychologist and the social worker were needed to achieve good results. The aim of the project was to define a method to provide individualized actions in order to favour psychophysical health of newborns and their families.

Humans↗

PubMed2000

[Neonatal cystic fibrosis: report of 2 cases].

Cystic fibrosis is the most common life-limiting recessive genetic disorder in Caucasian. It is caused by mutations of CFTR gene (cystic fibrosis transmembrane conductance regulator); at present over 500 mutations are known. Cystic fibrosis as a cause of respiratory distress in the neonate is quite rare. In neonatal period the most important clinical manifestations are meconium ileum and much rarely cholestatic jaundice. We present two cases of cystic fibrosis in newborns. In the first one, we point out the strict association between meconium ileum and cystic fibrosis. The patient underwent a surgical treatment for meconium ileum and the diagnosis was rapidly confirmed by genetic analysis and sweat test. The second one had intestinal obstruction from birth caused by meconium ileum associated with ileal atresia; besides, he developed cholestatic jaundice, severe and rapidly progressive respiratory disease. He died at 102 degrees day of age for cardiac failure. The diagnosis of cystic fibrosis, supported by typical clinical features and high level of serum trypsin, unfortunately wasn't confirmed by genetic analysis (lambda F508/neg), in addition, the sweat test wasn't reliable because an inadequate quantity of sweat was collected.

Cystic Fibrosis↗

PubMed1999

Chromosome aberrations induced by light ions: Monte Carlo simulations based on a mechanistic model.

PURPOSE: To investigate the mechanisms underlying the induction of chromosome aberrations by ionizing radiation, focusing attention on DNA damage severity, interphase chromosome geometry and the distribution of DNA strand breaks. METHODS: An ab initio biophysical model of aberration induction in human lymphocytes specific for light ions was developed, based on the assumption that 'complex lesions' (clustered DNA breaks) produce aberrations, whereas less severe breaks are repaired. It was assumed that interphase chromosomes are spatially localized and that chromosome break free-ends rejoin pairwise randomly; the unrejoining of a certain fraction of free-ends was assumed to be possible, and small fragments were neglected in order to reproduce experimental conditions. The yield of different aberrations was calculated and compared with some data obtained using Giemsa or FISH techniques. RESULTS: Dose-response curves for dicentrics and centric rings (Giemsa) and for reciprocal, complex and incomplete exchanges (FISH) were simulated; the ratio between complex and reciprocal exchanges was also calculated as a function of particle type and LET. The results showed agreement with data from lymphocyte irradiation with light ions. CONCLUSIONS: The results suggest that clustered DNA breaks are a critical damage type for aberration induction and that interphase chromosome localization plays an important role. Moreover, the effect of a given particle type is related both to the number of induced complex lesions and to their spatial distribution.

Alpha Particles↗

PubMed1998

Assessment of left ventricular dyssynergy by color kinesis.

Color kinesis is a new echocardiographic technique based on acoustic quantification. It has been developed to facilitate the ability to identify contraction abnormalities and has been incorporated into a commercially available ultrasound imaging system. The potential of this technique to improve the qualitative and quantitative assessment of wall motion abnormalities is described. Evaluation of color-encoded images allows detection of decreased amplitude of endocardial motion in abnormally contracting segments as well as a shorter time of endocardial excursion in segments with severely decreased motion. Compared with off-line quantitative studies, color kinesis has the advantage to be used on-line, without time-consuming manual tracing of endocardial boundaries. In addition, a single end-systolic color image contains the entire picture of spatial and temporal contraction and can be digitally stored and retrieved. In patients with proven coronary artery disease, color kinesis had a sensitivity of 88%, a specificity of 77%, and an overall accuracy of 86% in identifying the presence of segmental dysfunction. The practical application of color kinesis might be to improve our ability to distinguish normal from hypokinesis, something that has always been difficult in clinical echocardiography. Segmental analysis of color kinesis images allows objective detection of dobutamine-induced regional wall motion abnormalities in agreement with conventional visual interpretation of the corresponding 2-dimensional views. A method for objective assessment of wall dynamics during dobutamine stress echocardiography would be of particular clinical value, because these images are even more difficult to interpret than conventional echocardiograms. Quantitative assessment of diastolic function may allow objective evaluation of segmental relaxation abnormalities, especially under conditions of pharmacologic stress testing. Acquisition of color kinesis images during dobutamine stress echocardiography, both transthoracic and transesophageal, may facilitate the assessment of hybernating but viable myocardium and enhance the sensitivity in the detection of coronary artery disease.

Echocardiography, Doppler, Color↗

PubMed1998

Effects of melanin on high- and low- linear energy transfer (LET) radiation response of human epithelial cells.

The search for effective radioprotectors is of major concern in the medical, military, environmental, and space sciences. Conventional radioprotectors are generally effective only during a single irradiation and display their radioprotective properties only at high, toxic concentrations. In addition, they reduce somatic radiation effects but are poorly efficient in protecting from hereditary stochastic radiation effects. In this respect, the pigment melanin merits attention. Experiments referring to potential melanin effects on the ionising radiation response have been carried out with different biological systems, both in vivo and in vitro. In this paper, we present results on the response to high- and low-linear energy transfer (LET) radiation of a human mammary epithelial cell line, H184B5 F5-1 M/10, supplemented by melanin. The incorporation of auto-oxidative (L-dopa) melanin was linear for concentrations from 3 to 10 micrograms/ml in the growth medium. Concentrations of up to 250 micrograms/ml did not significantly impair the cells proliferative ability. No significant protective effect of melanin on the survival of cultured cells after exposure to alpha-particles (130 keV/micron) or x-rays was observed.

Alpha Particles↗

PubMed1998

Role of the central endogenous opiate system in patients with syndrome X.

BACKGROUND: To evaluate the role of the endogenous opioid system (EOS) in abnormal pain perception in patients with syndrome X, we used a neuroendocrine approach, evaluating plasmatic luteinizing hormone (LH) changes after naloxone, a competitive antagonist of opioid receptors able to unblock tonic EOS inhibition on gonadotropin release. Thus LH response to naloxone test indicates the central EOS activity on hypothalamic luteinizing hormone-releasing hormone (LH-RH) inhibitory opioid receptors. METHODS: Ten patients with syndrome X, 10 age-matched male patients with coronary artery disease (CAD), and 10 normal subjects were analyzed. Naloxone tests were performed between 8 and 9 am. Basal beta-endorphin and LH levels were determined on 4 blood samples at 20-minute intervals; after naloxone (0.1 mg/kg intravenously in 4 minutes), LH was measured on 8 samples at 15-minute intervals. In all patients the test was also performed after LH-RH administration. Anginal pain on exercise testing was subjectively scored on a 1 to 10 analogic scale and wall motion abnormalities were quantified by a wall motion score index. RESULTS: Significant differences were found in LH release after naloxone (CAD 260.3 +/- 42.6 vs syndrome X 151.6 +/- 48.5 mIU/mL, P <.05), angina score (CAD 5.5 +/- 1.3 vs syndrome X 7.2 +/- 1.7, P <.05), and wall motion abnormalities (CAD 3.6 +/- 1. 2 vs syndrome X 2.8 +/- 1.9, P <.05). CONCLUSIONS: The reduced LH release after naloxone in syndrome X, with a normal LH-RH response, suggests a lower central EOS activity, which may be related to the higher anginal pain perception.

Humans↗

PubMed1998

The effect of track structure on the induction of chromosomal aberrations in murine cells.

PURPOSE: To measure chromosome aberrations in C3H 10T1/2 mouse fibroblasts using FISH painting at the first mitosis following exposure to 30 keV/microm hydrogen or neon ions. MATERIALS AND METHODS: Cells in plateau-phase were irradiated with 0.86 MeV protons at the TTT-3 Tandem accelerator in Naples (Italy), or with 400 MeV/n Ne ions at the HIMAC accelerator in Chiba (Japan). Colcemid-blocked cells were harvested at the first mitosis following exposure, and chromosome spreads were hybridized in situ with a fluorescein-labelled composite mouse DNA probe specific for chromosomes 2 and 8. RESULTS: Protons were more efficient than neon ions at the same LET in the induction of chromosome interchanges and breaks. Yields of complex exchanges were similar for both particles at the same dose, but protons produced mostly insertions, while with Ne exposure non-reciprocal exchanges were the most frequent complex-type exchange. CONCLUSIONS: Charged particles with the same LET produce different yields of chromosome aberrations, and some observed differences can be explained based on the available track-structure models.

Animals↗

PubMed1998

Rejoining and misrejoining of radiation-induced chromatin breaks. IV. Charged particles.

We have recently reported the kinetics of chromosome rejoining and exchange formation in human lymphocytes exposed to gamma rays using the techniques of fluorescence in situ hybridization (FISH) and premature chromosome condensation (PCC). In this paper, we have extended previous measurements to cells exposed to charged particles. Our goal was to determine differences in chromatin break rejoining and misrejoining after exposure to low- and high-linear energy transfer (LET) radiation. Cells were irradiated with hydrogen, neon, carbon or iron ions in the LET range 0.3-140 keV/microm and were incubated at 37 degrees C for various times after exposure. Little difference was observed in the yield of early prematurely condensed chromosome breaks for the different ions. The kinetics of break rejoining was exponential for all ions and had similar time constants, but the residual level of unrejoined breaks after prolonged incubation was higher for high-LET radiation. The kinetics of exchange formation was also similar for the different ions, but the yield of chromosome interchanges measured soon after exposure was higher for high-LET particles, suggesting that a higher fraction of DNA breaks are misrejoined quickly. On the other hand, the rate of formation of complete exchanges was slightly lower for densely ionizing radiation. The ratios between the yields of different types of aberrations observed at 10 h postirradiation in prematurely condensed chromosome preparations were dependent on LET. We found significant differences between the yields of aberrations measured in interphase (after repair) and metaphase for densely ionizing radiation. This difference might be caused by prolonged mitotic delay and/or interphase death. Overall, the results point out significant differences between low- and high-LET radiation for the formation of chromosome aberrations.

Animals↗

PubMed1997

Phenotype expression of human bone cells cultured on implant substrates.

Bone cells derived from the human jaw were cultured on titanium, titanium coated with hydroxyapatite (THA) or with plasma spray (TPS) to study the behaviour of the cells anchored to implant substrates. Bone cells were cultured in MEM with the addition of [3H]-thymidine to evaluate cellular proliferation, and [3H]-glucosamine to evaluate GAG synthesis and accumulation in the extra-cellular matrix (ECM). Moreover, to study the degradation of GAG bone cells were cultured in the presence of NH4Cl, an amine known to inhibit lysosomal activity. Our results show that TPS is the substrate that favours both cellular proliferation and the accumulation of GAG in the ECM.

Ammonium Chloride↗

PubMed1997

Inactivation of individual mammalian cells by single alpha-particles.

PURPOSE: To measure clonogenic death of Chinese hamster V79 cells following exposure to a defined number of 4.3 MeV alpha-particles (track-averaged LET = 105 keV/micron). MATERIALS AND METHODS: Cells were irradiated at the radiobiological facility installed at the TTT-3 Tandem accelerator in Naples by using a 'Biostack' approach, which allows the positions of incident tracks relative to cells to be carefully determined. Subcellular structure was identified by fluorescence microscopy, while tracks were visualized by LR-115 solid state nuclear track detectors. RESULTS: Particle hits in the cytoplasm did not significantly affect cell survival, yet survival probability decreased exponentially as a function of the number of nuclear traversals. Measured probability of surviving to exactly one 4.3 MeV alpha-particle traversal in the cell nucleus was 0.67 +/- 0.10. Inactivation cross-section was substantially higher than expected from conventional survival curves. However, folding of the data with Poisson statistics showed that survival level expected if a mean of one alpha-particle goes through a nucleus is higher than the measured value after exactly one particle traversal. CONCLUSIONS: V79 cells have about 67% probability to survive a single alpha-particle traversal in the cell nucleus. Single-particle survival curves are consistent with conventional dose-survival relationships, once Poisson distribution of traversals is taken into account.

Alpha Particles↗

PubMed1997

Phenotype expression of gingival fibroblasts cultured on membranes used in guided tissue regeneration.

Human gingival fibroblasts were cultured in vitro using as substrates an extracellular matrix (matrix) and polytetrafluoride (PTFE) membranes, which are used in guided tissue regeneration. To test the degree of biocompatibility of these membranes, the cellular proliferation and the accumulation of extracellular matrix (ECM) macromolecules were considered as parameters. The fibroblasts were cultured in vitro for 24 and 48 hours without serum on plastic, matrix, and PTFE membranes in the presence of 3H-thymidine, 3H-glucosamine, and 3H-proline to study the neo-synthesis of DNA, glycosaminoglycans (GAG), and collagen proteins, respectively. Studies on cell proliferation showed that fibroblasts grown on matrix membrane significantly increased 3H-thymidine incorporation, while fibroblasts grown on PTFE membrane decreased 3H-thymidine incorporation, compared to plastic used as a control. Moreover, the PTFE membrane induced a marked decrease of collagen and GAG accumulation both in the cellular and extracellular pool, while the matrix membrane provoked a decrease of the two macromolecules in the cellular pool and an increase in the extracellular one, compared to the control. The data we obtained demonstrate that matrix membranes are the most suitable to stimulate both cellular proliferation and ECM macromolecule accumulation.

Adult↗

PubMed1996

Helicobacter pylori and proteolytic activity.

Protease activity of 10 different H. pylori strains, purified marker proteases and protease-positive reference bacteria (Klebsiella ozaenae, Serratia marcescens) were tested against bovine haemoglobin, porcine mucin, bovine serum albumin, gelatin and casein as substrates. After incubation in development buffer and subsequent staining with Coomassie blue, protease activity bands were demonstrated as transparent spots after polyacrylamide gel electrophoresis (PAGE) on gels with incorporated substrate. Presence of protease activity was investigated in a wide pH range (pH 2.0-9.0). Although marker proteases (0.15-0.2 microgram per slot) as well as protease-positive bacteria (2-30 micrograms per slot) clearly showed proteolytic activity in gels containing 0.1-0.2% protein mL-1, no proteolytic activity was demonstrated in any of the H. pylori strains tested. This finding indicates that H. pylori does not possess significant protease activity, as this would have been detected by this sensitive method.

Biopsy↗

PubMed1996

Metal substrates influence the release of glycosaminoglycan and transforming growth factor beta by human bone cells.

Bone cells derived from human jaw were isolated from explants and grown in vitro. Subcultures were cultured on plastic (control) and metal substrates for 24 and 48 hours in medium containing 3H-glucosamine and labeled glycosaminoglycan (GAG) accumulation was measured. In bone cells cultured on metal substrates there was an evident reduction in the synthesis and secretion of radiolabeled macromolecules compared to bone cells cultured on plastic. Moreover, the accumulation of single GAG classes was specific for each substrate tested. The results showed that titanium was the only metal substrate studied in which the percentage of individual GAG classes remained the same as control cultures. GAG reduction was due to a decreased synthesis and not to an increased degradation as shown by the decrement of exoglycosidase activity. The metals also reduced the activity of transforming growth factor beta (TGF beta), measured using interleukin-1 assay method, a factor involved in the various phases of bone remodeling; in this case, too, cells grown on titanium showed the highest TGF beta activity compared to the other metal substrates studied. The results indicate that the substrate to which the cells adhere do exhibit specific differences in GAG composition and TGF beta activity. The differences observed may be important during in vivo events such as guided tissue regeneration and bone deposition.

Acetylglucosaminidase↗

PubMed1995

Effects of alpha-particles on survival and chromosomal aberrations in human mammary epithelial cells.

We have studied the radiation responses of a human mammary epithelial cell line, H184B5 F5-1 M/10. This cell line was derived from primary mammary cells after treatment with chemicals and heavy ions. The F5-1 M/10 cells are immortal, density-inhibited in growth, and non-tumorigenic in athymic nude mice and represent an in vitro model of the human epithelium for radiation studies. Because epithelial cells are the target of alpha-particles emitted from radon daughters, we concentrated our studies on the efficiency of alpha-particles. Confluent cultures of M/10 cells were exposed to accelerated alpha-particles [beam energy incident at the cell monolayer = 3.85 MeV, incident linear energy transfer (LET) in cell = 109 keV/microns] and, for comparison, to 80 kVp x-rays. The following endpoints were studied: (1) survival, (2) chromosome aberrations at the first postirradiation mitosis, and (3) chromosome alterations at later passages following irradiation. The survival curve was exponential for alpha-particles (D0 = 0.73 +/- 0.04 Gy), while a shoulder was observed for x-rays (alpha/beta = 2.9 Gy; D0 = 2.5 Gy, extrapolation number 1.6). The relative biological effectiveness (RBE) of high-LET alpha-particles for human epithelial cell killing was 3.3 at 37% survival. Dose-response curves for the induction of chromosome aberrations were linear for alpha-particles and linearquadratic for x-rays. The RBE for the induction of chromosome aberrations varied with the type of aberration scored and was high (about 5) for chromosome breaks and low (about 2) for chromosome exchanges.(ABSTRACT TRUNCATED AT 250 WORDS)

Alpha Particles↗

PubMed1994

The effect of space location on neglect depends on the nature of the task.

It has been often reported that in patients with visual neglect line bisection is more accurate in the right than in the left hemispace. However, no data are available on the effect of hemispace on reading errors associated with neglect. We examined a 62-year-old man who presented with severe left neglect following a large infarction in the right cerebral hemisphere. The patient was asked to read 180 words aloud and to bisect 90 lines. Stimuli were presented in three different spatial locations: across the centre, to the right or to the left of the body midline. Line bisection was significantly more accurate in the right hemispace compared with the centre, or the left hemispace. In contrast, reading was significantly more accurate with words presented on the left side than on the centre or right side. This is the first time that such dissociation has been reported. We hypothesize that the dissociation depends on the nature of the stimuli and on the different cognitive demands of the tasks.

Cerebrovascular Disorders↗

PubMed1994

The induction of Robertsonian translocations by X-rays and mitomycin C in mouse cells.

The induction of Robertsonian translocations in murine C3H 10T1/2 embryo fibroblasts after exposure to X-rays and mitomycin C has been investigated. Cells were irradiated in log-phase and harvested at different times for chromosome analysis. The stage of the cell cycle of individual cells at the time of irradiation could be determined by differential replication staining. A dose-dependent delay in the progression through S- and G2-phase has been observed. X-rays produced an increase in the frequency of Robertsonian translocations when cells were exposed in G1- or S-phase, but not in G2. The dose-response curve for the induction of Robertsonian translocations both in G1 and S peaked at 2 Gy and slightly declined at higher doses. For G2 cells, an increase compared to the control level was observed only after 1 Gy. Mitomycin C induced chromosomal aberrations and Robertsonian translocations in 10T1/2 cells, but no significant interaction between ionizing radiation and the alkylating agent was observed for these two endpoints. However, the combined exposure caused satellite associations of chromosomes. Both the number of satellite associations/metaphase (five times the frequency observed after mitomycin C alone) and the number of chromosomes/satellite (up to 10 chromosomes were observed in satellite associations) were greatly enhanced compared to X-rays and mitomycin C alone.

Animals↗