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Biomedical subjects

P Orlando

Publications and source records attributed to P Orlando.

At least 19 recordsLinked to original sources
PubMed2006

Fungal contamination in hospital environments.

OBJECTIVES: To assess the degree of fungal contamination in hospital environments and to evaluate the ability of air conditioning systems to reduce such contamination. METHODS: We monitored airborne microbial concentrations in various environments in 10 hospitals equipped with air conditioning. Sampling was performed with a portable Surface Air System impactor with replicate organism detection and counting plates containing a fungus-selective medium. The total fungal concentration was determined 72-120 hours after sampling. The genera most involved in infection were identified by macroscopic and microscopic observation. RESULTS: The mean concentration of airborne fungi in the set of environments examined was 19 +/- 19 colony-forming units (cfu) per cubic meter. Analysis of the fungal concentration in the different types of environments revealed different levels of contamination: the lowest mean values (12 +/- 14 cfu/m(3)) were recorded in operating theaters, and the highest (45 +/- 37 cfu/m(3)) were recorded in kitchens. Analyses revealed statistically significant differences between median values for the various environments. The fungal genus most commonly encountered was Penicillium, which, in kitchens, displayed the highest mean airborne concentration (8 +/- 2.4 cfu/m(3)). The percentage (35%) of Aspergillus documented in the wards was higher than that in any of the other environments monitored. CONCLUSIONS: The fungal concentrations recorded in the present study are comparable to those recorded in other studies conducted in hospital environments and are considerably lower than those seen in other indoor environments that are not air conditioned. These findings demonstrate the effectiveness of air-handling systems in reducing fungal contamination.

Air Conditioning↗
PubMed2004

A study about remedial measures to reduce 222Rn concentration in an experimental building.

Radon gas emanating from underground can spread to adjoining closed areas. It can concentrate and reach levels which represent a risk to people's health. It is well known that radon presence in most areas depends mainly on the area's geological features. Indoor radon concentrations further depend on the type of structure, construction materials and the technology used for the building. Therefore, indoor radon monitoring is of primary importance for deciding whether remedial measures are to be adopted for reducing harmful concentrations. This approach has been tried by measuring radon concentration in an experimental building situated in Milan (Italy). This building situated in a geological area that is considered at low radon risk. The results were obtained after analysing radon concentration in indoor rooms, crawl spaces, soil gas and in the atmosphere outside and by measuring before and after adoption of remedial measures. The study shows that improper building design can give rise to higher indoor radon accumulation even in an area of poor radon exhalation. Furthermore, the results enable quantification of the effectiveness of the remedial measures.

Air Pollution, Indoor↗
PubMed2003

Factors influencing hospital infection control policies in Italian hospitals.

A study was undertaken to determine the resources available in Italian hospitals for the control of nosocomial infections and the factors favouring a successful approach. During January-May 2000 a questionnaire about infection control was sent to the hospital health director of all Italian National Health System hospitals treating acute patients and with more than 3500 admissions in 1999. An active programme was defined as a hospital infection control committee (HICC) meeting at least four times in 1999, the presence of a doctor with infection control responsibilities, a nurse employed in infection control and at least one surveillance activity and one infection control guideline issued or updated in the past two years. There was a response rate of 87.5% (463/529). Almost fifteen percent (69/463) of hospitals had an active programme for Infection Control and 76.2% (353/463) had a HICC. Seventy-one percent (330/463) of the hospitals had a hospital infection control physician and 53% (250/463) had infection control nurses. Fifty-two percent (242/463) reported at least one surveillance activity and 70.8% (328/463) had issued or updated at least one guidance document in the last two years. The presence of regional policies [odds ratio (OR) 8.7], operative groups (OR 4.2), at least one full-time nurse (OR 4.6) and a hospital annual plan which specified infection control (OR 2.1) were statistically associated with an active programme in the multivariate analysis.

Cross Infection↗
PubMed2002

Factors affecting individual exposure to NO2 in Genoa (northern Italy).

The individual exposure to nitrogen dioxide (NO2) of 89 volunteers living in Genoa, a large port city of northern Italy, was investigated with personal passive diffusion tubes in February-March 2000. The data were related to NO2 concentration in the kitchen and bedroom as measured by static samplers. Volunteers included students, workers and housewives living in three areas of Genoa differing by street traffic and industrial plant location. The kitchen samples showed higher (47.00+/-16.5 microg/m3) NO2 concentrations than those from the bedroom (24.78+/-9.8 microg/m3); overall indoor NO2 concentrations were lower in the Eastern area of Genoa, where outdoor pollution is lower. Students were the volunteer group with the lowest exposure rate (24.9+/-7.8 microg/m3 vs. 44.3+/-10.1 microg/m3 for workers and 40.0+/-13.4 microg/m3 for housewives). This difference is related to the fact that students spend more time indoors, where pollution levels are lower. The main household characteristics which were shown to affect personal NO2 exposure were (a) the presence of a chimney equipped with an active aspiration device in the kitchen and (b) the heating system.

Activities of Daily Living↗
PubMed2001

Control by the endogenous cannabinoid system of ras oncogene-dependent tumor growth.

We investigated the effect of 2-methyl-arachidonyl-2'-fluoro-ethylamide (Met-F-AEA), a stable analog of the endocannabinoid anandamide, on a rat thyroid epithelial cell line (FRTL-5) transformed by the K-ras oncogene, and on epithelial tumors derived from these cells. Met-F-AEA effect in vivo was evaluated in a nude mouse xenograft model, where K-ras-transformed (KiMol) cells were implanted subcutaneously. Met-F-AEA (0.5 mg/kg/dose) induced a drastic reduction in tumor volume. This effect was inhibited by the CB1 receptor antagonist SR141716A (0.7 mg/kg/dose) and was accompanied by a strong reduction of K-ras activity. Accordingly, KiMol cells and tumors express CB1 receptors. Met-F-AEA inhibited (IC50 ~5 mM) the proliferation in vitro and the transition to the S phase of KiMol cells and it reduced K-ras activity; these effects were antagonized by SR141716A. Met-F-AEA cytostatic action was significantly smaller in nontransformed FRTL-5 cells than in KiMol cells. Met-F-AEA treatment exerted opposite effects on the expression of CB1 receptors in KiMol and FRTL-5 cells, with a strong up-regulation in the former case and a suppression in nontransformed cells. The data suggest that: 1) Met-F-AEA inhibits ras oncogene-dependent tumor growth in vivo through CB1 cannabinoid receptors; and 2) responsiveness of FRTL-5 cells to endocannabinoids depends on whether or not they are transformed by K-ras.

Animals↗
PubMed2001

Palmitoylethanolamide inhibits the expression of fatty acid amide hydrolase and enhances the anti-proliferative effect of anandamide in human breast cancer cells.

Palmitoylethanolamide (PEA) has been shown to act in synergy with anandamide (arachidonoylethanolamide; AEA), an endogenous agonist of cannabinoid receptor type 1 (CB(1)). This synergistic effect was reduced by the CB(2) cannabinoid receptor antagonist SR144528, although PEA does not activate either CB(1) or CB(2) receptors. Here we show that PEA potently enhances the anti-proliferative effects of AEA on human breast cancer cells (HBCCs), in part by inhibiting the expression of fatty acid amide hydrolase (FAAH), the major enzyme catalysing AEA degradation. PEA (1-10 microM) enhanced in a dose-related manner the inhibitory effect of AEA on both basal and nerve growth factor (NGF)-induced HBCC proliferation, without inducing any cytostatic effect by itself. PEA (5 microM) decreased the IC(50) values for AEA inhibitory effects by 3-6-fold. This effect was not blocked by the CB(2) receptor antagonist SR144528, and was not mimicked by a selective agonist of CB(2) receptors. PEA enhanced AEA-evoked inhibition of the expression of NGF Trk receptors, which underlies the anti-proliferative effect of the endocannabinoid on NGF-stimulated MCF-7 cells. The effect of PEA was due in part to inhibition of AEA degradation, since treatment of MCF-7 cells with 5 microM PEA caused a approximately 30-40% down-regulation of FAAH expression and activity. However, PEA also enhanced the cytostatic effect of the cannabinoid receptor agonist HU-210, although less potently than with AEA. PEA did not modify the affinity of ligands for CB(1) or CB(2) receptors, and neither did it alter the CB(1)/CB(2)-mediated inhibitory effect of AEA on adenylate cyclase type V, nor the expression of CB(1) and CB(2) receptors in MCF-7 cells. We suggest that long-term PEA treatment of cells may positively affect the pharmacological activity of AEA, in part by inhibiting FAAH expression.

Amides↗
PubMed2001

Synthesis and applications of chitosan mercaptanes as heavy metal retention agent.

Chitosan, poly-beta(1-->4)-2 amino-2-deoxy-D-Glucopyranose is a biopolymer obtained by extensive deacetylation of chitin [poly-beta(1-->4)-2-acetamide-2-deoxy-D-Glucopyranose], main constituent of crustacean shells. The present study was carried out using crab shells from nylon shrimps (Heterocarpus reedi). Despite the abundance of raw material in our environment, little work has been published in this field using derivatives. The main goal of this work is to develop a good method to prepare chitosan mercaptanes derivatives using mercaptoacetic acid and 1-chloro-2,3-epoxy propane propionic acid. The evaluation of the retention capacities using several concentrations of copper and mercury solutions with concentrations ranging from 10 to 104 ppm at pH 2.5 and 4.5 are tested. A comparison of the absorption isotherms with Langmuir isotherms is also reported. Full characterization of the derivatives was carried out using FTIR, elemental analysis and TGA. The morphology of chitosan and derivatives is compared before and after treating polymers with mercury and copper ions.

Adsorption↗
PubMed2001

[Autoantibodies in chronic hepatitis C. Markers of autoimmunity or non-specific events?].

In the light of the high prevalence of non organ-specific autoantibodies in chronic hepatitis C, the possibility that such a finding may represent the consequence of a viral, autoimmune or overlapping disease should be considered, which may in turn require a different therapeutical approach. It is known, anyway, that the diagnosis of autoimmune hepatitis is based on a set of epidemiological, clinical, biochemical, histological criteria and autoantibody pattern. In 113 cases of chronic hepatitis with HCV infection, we determined the presence of non organ-specific autoantibodies [anti-nuclear (ANA), anti-smooth muscle (SMA), anti-liver-kidney microsomal antibodies (LKM), anti-mithocondrial antibodies (AMA)] and described the epidemiological, clinical, biochemical, histological characteristics and therapeutic response to interferon. 40 patients (35%) exhibited non organ-specific autoantibodies: 25 patients were SMA positive (Vasal pattern), 4 ANA positive (Speckled pattern), 7 ANA (Speckled pattern) + SMA (Vasal pattern) positive and 4 LKM positive. All subjects with HCV infection and autoantibodies did not display additional criterias of autoimmunity, including the same outcome to interferon therapy when compared to HCV positive patients without autoantibodies. The failure to determine clinical features, associated to autoimmunity in HCV positive patients with autoantibodies, suggests that autoantibody occurrence may represent a fortuitous event during the course of HCV infection.

Autoantibodies↗
PubMed2000

Suppression of nerve growth factor Trk receptors and prolactin receptors by endocannabinoids leads to inhibition of human breast and prostate cancer cell proliferation.

Anandamide and 2-arachidonoylglycerol (2-AG), two endogenous ligands of the CB1 and CB2 cannabinoid receptor subtypes, inhibit the proliferation of PRL-responsive human breast cancer cells (HBCCs) through down-regulation of the long form of the PRL receptor (PRLr). Here we report that 1) anandamide and 2-AG inhibit the nerve growth factor (NGF)-induced proliferation of HBCCs through suppression of the levels of NGF Trk receptors; 2) inhibition of PRLr levels results in inhibition of the proliferation of other PRL-responsive cells, the prostate cancer DU-145 cell line; and 3) CB1-like cannabinoid receptors are expressed in HBCCs and DU-145 cells and mediate the inhibition of cell proliferation and Trk/PRLr expression. Beta-NGF-induced HBCC proliferation was potently inhibited (IC50 = 50-600 nM) by the synthetic cannabinoid HU-210, 2-AG, anandamide, and its metabolically stable analogs, but not by the anandamide congener, palmitoylethanolamide, or the selective agonist of CB2 cannabinoid receptors, BML-190. The effect of anandamide was blocked by the CB1 receptor antagonist, SR141716A, but not by the CB2 receptor antagonist, SR144528. Anandamide and HU-210 exerted a strong inhibition of the levels of NGF Trk receptors as detected by Western immunoblotting; this effect was reversed by SR141716A. When induced by exogenous PRL, the proliferation of prostate DU-145 cells was potently inhibited (IC50 = 100-300 nM) by anandamide, 2-AG, and HU-210. Anandamide also down-regulated the levels of PRLr in DU-145 cells. SR141716A attenuated these two effects of anandamide. HBCCs and DU-145 cells were shown to contain 1) transcripts for CB1 and, to a lesser extent, CB2 cannabinoid receptors, 2) specific binding sites for [3H]SR141716A that could be displaced by anandamide, and 3) a CB1 receptor-immunoreactive protein. These findings suggest that endogenous cannabinoids and CB1 receptor agonists are potential negative effectors of PRL- and NGF-induced biological responses, at least in some cancer cells.

Arachidonic Acids↗
PubMed2000

sICAM-1, sCD95 and sCD95L levels in chronic liver diseases of different etiology.

The release of soluble circulating molecules represents a prominent feature during the course of immune-mediated clinical conditions. To further assess the relationship between serum concentrations of adhesion or apoptotic-related soluble structures and liver diseases, we evaluated the levels of intercellular adhesion molecule-1 (sICAM-1), Fas receptor (CD95) and Fas ligand (sCD95L) in a group of patients affected by Hepatitis C Virus (HCV)-induced chronic hepatitis (CH-C), HCV-positive liver cirrhosis with superimposed hepatocellular carcinoma (HCC), autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and alcoholic liver cirrhosis (ALC). Results show that sICAM-1 values were in all instances significantly elevated when compared to those seen in healthy donors. Similar findings were noted in subjects with liver diseases in terms of sCD95 concentrations, even if to a different degree of statistical significance. Finally, sCD95L amounts were augmented in AIH, PBC, ALC and CH-C in comparison to controls, while in the HCC counterpart sCD95L levels fell within normal range. All together, these findings emphasize the occurrence of circulating soluble molecules in patients with various chronic liver diseases, likely reflecting the involvement of several pathogenetic mechanisms.

Adult↗
PubMed1999

Biosynthesis and inactivation of the endocannabinoid 2-arachidonoylglycerol in circulating and tumoral macrophages.

The stimulus-induced biosynthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG) in intact mouse J774 macrophages and the inactivation of 2-AG by the same cells or by rat circulating macrophages was studied. By using gas chromatography-mass spectrometry, we found that ionomycin (5 microM) and lipopolysaccharide (LPS, 200 microg x mL-1) cause a 24-fold and 2.5-fold stimulation of 2-AG levels in J774 cells, respectively, thus providing unprecedented evidence that this cannabimimetic metabolite can be synthesized by macrophages. In J774 cells, LPS also induced a 7.8-fold increase of the levels of the other endocannabinoid, anandamide, and, in rat circulating macrophages, an almost twofold increase of 2-AG levels. Extracellular [3H]2-AG was cleared from the medium of intact J774 macrophages (t1/2 = 19-28 min) and esterified to phospholipids, diacylglycerols and triglycerides or hydrolyzed to [3H]arachidonic acid and glycerol. These catabolic processes were attenuated differentially by various enzyme inhibitors. Rat circulating macrophages were shown to contain enzymatic activities for the hydrolysis of 2-AG, including: (a) fatty acid amide hydrolase (FAAH), the enzyme responsible for anandamide breakdown and previously shown to catalyse also 2-AG hydrolysis, and (b) a 2-AG hydrolase activity different from FAAH and down-regulated by LPS. High levels of FAAH mRNA were found in circulating macrophages but not platelets, which, however, contain a 2-AG hydrolase. Both platelets and macrophages were shown to express the mRNA for the CB1 cannabinoid receptor. A macrophage 2-AG hydrolase with apparent Km = 110 microM and Vmax = 7.9 nmol x min-1 x (mg protein)-1 was partially characterized in J774 cells and found to exhibit an optimal pH of 6-7 and little or no sensitivity to typical FAAH inhibitors. These findings demonstrate for the first time that macrophages participate in the homeostasis of the hypotensive and immunomodulatory endocannabinoid 2-AG through metabolic mechanisms that are subject to regulation.

Animals↗
PubMed1999

Kelletinin A, from the marine mollusc Buccinulum corneum, promotes differentiation in Hydra vulgaris.

The effects of kelletinin A [ribityl pentakis (p-hydroxybenzoate)] (KA), a natural compound isolated from the marine gastropod Buccinulum corneum, were studied in vivo in Hydra vulgaris during regeneration. KA caused a marked increase of regenerated tentacle numbers (ATN) and promoted transdifferentiation of epithelial cells into battery cells, and nematocyte differentiation. Morphological data were correlated to changes in acid and alkaline phosphatase levels, enzymes that have been described as regeneration markers.

Acid Phosphatase↗
PubMed1998

Multiple forms of DNA polymerase from the thermo-acidophilic eubacterium Bacillus acidocaldarius: purification, biochemical characterization and possible biological role.

Two DNA polymerase isoenzymes, called DpA and DpB on the basis of their elution order from DEAE cellulose, were purified to homogeneity from the thermo-acidophilic eubacterium Bacillus acidocaldarius. The enzymes are weakly acidophilic proteins constituted by a single subunit of 117 and 103 kDa respectively. DpA and DpB differ in thermostability, in thermophilicity, in sensitivity to assay conditions and in resistance to sulphydryl-group blocking agents such as N-ethylmaleimide and p-hydroxymercuriobenzoate. They differ also in synthetic template-primer utilization, in the apparent Km for dNTPs and in processivity. In particular, DpA utilizes more effic iently synthetic templates-primers such as poly(dA).poly(dT), poly(dT). (rA)12-18 and poly(rA).(dT)12-18 and presents a greater tendency to accept dNTP analogues modified in the sugar or in the base ring, such as cytosine beta-d-arabinofuranoside 5'-triphosphate, 2',3'-dideoxyribonucleosides 5'-triphosphate, butylphenyl-dGTP and digoxigenin-conjugated dUTP. In addition, DpA presents an exonuclease activity that preferentially hydrolyses DNA in the 5'-3' direction, whereas DpB lacks this activity. The possible biological role of the enzymes is discussed.

Bacillus↗
PubMed1996

Novel diterpenoid diacylglycerols from marine molluscs: potent morphogens and protein kinase C activators.

Five novel 1,2-sn-diacylglycerols with diterpenoid acyl moieties in the sn-1 position were isolated and characterized, together with the corresponding 1,3-sn-diacylglycerols, from three species of dorid nudibranchs molluscs. Their potent activity as morphogens in vivo in the Hydra tentacle regeneration assay and their parallel activity as activators of rat brain protein kinase C (PKC) in vitro are reported here. Our findings promote the use of these compounds as useful molecular probes for both in vivo and in vitro studies on the participation of PKC in cell development.

Animals↗
PubMed1996

Inhibition mechanisms of HIV-1, Mo-MuLV and AMV reverse transcriptases by Kelletinin A from Buccinulum corneum.

Kelletinin A [ribity pentakis (p-hydroxybenzoate)] (KA), an inhibitor of HTLV-1 replication isolated from Buccinulum corneum, showed a noncompetitive inhibitory activity with respect to the template primer and to dTTP in the poly(rA).oligo(dT)12-18-directed reaction of HIV-1, Mo-MuLV and AMV reverse transcriptases (RT). Analysis of natural and synthetic KA-related compounds showed that the inhibitory activity was strictly related to the structural peculiarities of the molecule. In the presence of DNA as template primer the inhibition mechanism was drastically modified: HIV-1 RT activity was stimulated by low concentrations of KA and was inhibited by increasing the concentration of the compound, while Mo-MuLV and AMV activities were irreversibly inhibited by the formation of a non-reactive complex. The RNase H activities of these RTs were not affected by KA. The results of this study suggest a different mechanism of interaction of Kelletinins with HIV-1 RT compared with other non-nucleoside inhibitors. A possible use of these drugs in combination therapy and in the design of structure-based reverse transcriptase inhibitors is discussed.

Animals↗
PubMed1996

An experimental set-up to study carbon, water, and nitrate uptake rates by hydroponically grown plants.

The experimental system described allows concomitant hourly measurements of CO2, H2O, and NO3 uptake rates by plants grown hydroponically in a greenhouse. Plants are enclosed in an airtight chamber through which air flows at a controlled speed. Carbon dioxide exchange and transpiration rates are determined from respective differences of concentrations of CO2 and water vapor of the air at the system inlet and outlet. This set-up is based on the "open-system" principle with improvements made on existing systems. For instance, propeller anemometers are used to monitor air flow rates in the chamber. From their signal it is possible to continuously adjust air speed to changing environmental conditions and plant activity. The air temperature inside the system therefore never rises above that outside. Water and NO3 uptake rates are calculated at time intervals from changes in the volume and the NO3 concentration of the nutrient solution in contact with the roots. The precise measurement of the volume of solution is achieved using a balance which has a higher precision than any liquid level sensors. Nitrate concentration is determined in the laboratory from aliquots of solution sampled at time intervals. A number of test runs are reported which validate the measurements and confirm undisturbed conditions within the system. Results of typical diurnal changes in CO2, H2O, and NO3 uptake rates by fruiting tomato plants are also presented.

Air Conditioning↗
PubMed1995

Antimitotic and antiviral activities of Kelletinin A in HTLV-1 infected MT2 cells.

Kelletinin A [ribityl-pentakis (p-hydroxybenzoate)] (KA), a natural compound isolated from the marine gastropod Buccinulum corneum, showed antiviral activity on the human T-cell leukemia virus type-1 (HTLV-1) and antimitotic activity on HTLV-1-infected MT2 cells. KA inhibited cellular DNA and RNA synthesis, without influencing protein synthesis, and interfered with viral transcription by reducing the levels of high molecular weight transcripts. Finally, the compound inhibited HTLV-1 reverse transcriptase in vitro.

Antineoplastic Agents↗