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S Marchese

Publications and source records attributed to S Marchese.

At least 19 recordsLinked to original sources
PubMed2006

Noninvasive positive-pressure ventilation in ALS: predictors of tolerance and survival.

OBJECTIVE: To identify factors associated with tolerance and survival after noninvasive positive-pressure ventilation (NIPPV) and to investigate the influence of NIPPV on lung function in patients with ALS. METHODS: NIPPV was offered to 71 patients with ALS in accordance with currently published guidelines. Effects of NIPPV on lung function and factors influencing tolerance and survival after NIPPV were studied. RESULTS: Forty-four patients (61.9%; 95% CI: 50.6 to 73.2) tolerated NIPPV (NIPPV use >or=4 h/day) and 27 (38.1%; 95% CI: 26.8 to 49.4) were intolerant (NIPPV use <4 h/day). Patients with mild or moderate bulbar symptoms were more likely to tolerate NIPPV than those with severe impairment (odds ratio = 6.09, 95% CI: 1.18 to 31.52, p = 0.031). After NIPPV introduction, a slower decline in forced vital capacity (FVC) was observed in tolerant vs intolerant patients (p = 0.002). The slope of FVC decline after NIPPV initiation (risk ratio [RR]: 0.78, 95% CI: 0.65 to 0.94, p = 0.01) together with NIPPV tolerance (RR: 0.32, 95% CI: 0.13 to 0.78, p = 0.013) were the only independent predictors of survival in the overall group of patients. In multivariate analysis, body mass index was the most powerful predictor of longer survival after NIPPV in tolerant patients (RR: 0.77, 95% CI: 0.61 to 0.96, p = 0.022). CONCLUSION: Survival after noninvasive ventilation was independently related to ventilatory use (>or=4 h/day) and to the modifications of forced vital capacity decline after treatment initiation. The severity of bulbar impairment and the nutritional status of the ALS patients at the introduction of ventilation may predict tolerance and survival.

Aged↗
PubMed2005

A chart of failure risk for noninvasive ventilation in patients with COPD exacerbation.

Knowing the likelihood of failure of noninvasive positive pressure ventilation (NPPV) in patients with exacerbation of chronic obstructive pulmonary disease (COPD) could indicate the best choice between NPPV and endotracheal intubation instituted earlier. For this purpose, two risk charts were designed (at admission and after 2 h of NPPV) that included all relevant measurable clinical prognostic indicators derived from a population representing the patients seen routinely in clinical practice. Risk stratification of NPPV failure was assessed in 1,033 consecutive patients admitted to experienced hospital units, including two intensive care units, six respiratory intermediate care units, and five general wards. NPPV was successful in 797 patients. Patients with a Glasgow Coma Score <11, acute physiology and chronic health evaluation (APACHE) II > or =29, respiratory rate > or =30 breaths x min(-1) and pH at admission <7.25 have a predicted risk of failure >70%. A pH <7.25 after 2 h greatly increases the risk (>90%). The risk charts were validated on an independent group of 145 consecutive COPD patients treated with NPPV due to an acute ventilatory failure episode. To identify patients with a probability of failure >50%, the sensitivity and specificity were 33% and 96.7% on admission and 52.9% and 94.1% after 2 h of NPPV, respectively. The prediction chart, based on data from the current study, can function as a simple tool to predict the risk of failure of noninvasive positive pressure ventilation and thus improve clinical management of patients tailoring medical intervention.

APACHE↗
PubMed2001

Development of a method based on accelerated solvent extraction and liquid chromatography/mass spectrometry for determination of arylphenoxypropionic herbicides in soil.

A sensitive and specific analytical procedure for determining arylphenoxypropionic herbicides in soil samples, using Ionspray ionization (ISI) liquid chromatography/mass spectrometry (LC/MS), is presented. Arylphenoxypropionic acids are a new class of herbicides used for selective removal of most grass species from any non-grass crop, commercialized as herbicide esters. Previous studies have shown that the esters undergo fast hydrolysis in the presence of vegetable tissues and soil bacteria, yelding the corresponding free acid. The feasibility of rapidly extracting arylphenoxypropionic herbicides from soil by accelerated solvent extraction (ASE) techniques was evaluated. Four different soil samples were fortified with target compounds at levels of 5 and 20 ng/g by following a procedure able to mimic weathered soils. Herbicides were extracted by a methanol/water (80:20 v/v) solution (0.12 M) of NaCl at 90 degrees C. After clean-up using graphitized carbon black (GCB) as absorbent, the extract was analyzed by HPLC/ISI-MS. The effect of concentration of acid in the mobile phase on the response of ISI-MS was investigated. The effects of varying the orifice plate voltage on the production of diagnostic fragment ions, and on the response of the MS detector, were also investigated. The ISI-MS response was linearly related to the amounts of analytes injected between 1 and 200 ng. The limit of detection (signal-to-noise ratio = 3) of the method for the pesticides in soil samples was estimated to be less than 1 ng/g.

Acids↗
PubMed2001

Purification, cloning and characterisation of odorant- and pheromone-binding proteins from pig nasal epithelium.

Two distinct classes of lipocalin isoforms (OBP-IIs and OBP-IIIs) were purified and identified from porcine nasal mucosa of male and female individuals. Using primers designed on their N-terminal sequence, the complete primary structures of the mature polypeptides were determined. Mass spectrometry analysis confirmed the identity of the cDNA-derived sequences and provided information regarding their post-translational modifications. These species strongly resemble a lipocalin expressed by von Ebner's gland and salivary lipocalins carrying sex-specific pheromones secreted only by the boar's submaxillary glands. Both OBP-IIs and OBP-IIIs present two cysteines paired in a disulphide bond; the remaining residues occur in a reduced form. In addition, OBP-IIIs are heavily glycosylated and markedly different in their glycan moiety from the salivary lipocalins. A three-dimensional model is proposed based on protein species with known structure. Like salivary lipocalins, OBP-IIIs bind a number of odorant molecules, with highest affinity for the specific pheromone 5alpha-androst-16-en-3-one. The high similarity between OBPs from the nasal area and lipocalins from secretory glands suggests a common function in binding the same pheromonal ligands, the latter carrying chemical messages into the environment the former delivering them to specific receptors.

Amino Acid Sequence↗
PubMed2001

Bacterial expression and conformational analysis of a chemosensory protein from Schistocerca gregaria.

Chemosensory proteins (CSPs) are a class of small, soluble proteins present at high concentrations in chemosensory organs of different insect species. Several pieces of evidence suggest their involvement in carrying chemical messages from the environment to chemosensory receptors. However, a structural description of the mechanism of delivery has not been reported. In order to provide the first detailed conformational characterization of these molecules, we cloned a specific isoform (CSP-sg4) from Schistocerca gregaria and expressed it in Escherichia coli. The product was obtained with yields of more than 20 mg per L of culture, all in its soluble form. The recombinant protein was identical to the native one with respect to pairing of the disulfide bridges, aggregative state and secondary structure elements. Structural investigations revealed a significantly stable polypeptide with respect to variations in temperature and acidity. CD analysis, preliminary NMR data and secondary structure prediction pointed to a correctly folded structure where helical regions and loops are alternated in a similar fashion as that observed for other classes of odorant- and pheromone-binding proteins presenting no sequence similarity to CSPs.

Amino Acid Sequence↗
PubMed2000

Solid-phase extraction followed by high-performance liquid chromatography-ionspray interface-mass spectrometry for monitoring of herbicides in environmental water.

In this work we developed a sensitive and specific multiresidue method, based on reversed-phase liquid chromatography-mass spectrometry, with an ionspray interface (LC-ISI-MS), for determining 52 of most representative compounds of herbicides in water samples. The procedure used involved passing 0.5 l of surface water, 2 l of ground water and 4 l of drinking water samples, respectively, through a 0.5 g graphitized carbon black (GCB) extraction cartridge. Base-neutral and acid herbicides were differential eluted from GCB cartridge and follow analyzed by HPLC-ISI-MS apparatus. A conventional 4.6-mm-ID reversed-phase LC C18 column, operating with a mobile phase flow-rate of 1 ml/min, was used to chromatograph the analytes. A flow of 100 microl/min of the column effluent was diverted to the ISI source. The study demonstrates the sensitivity of the technique, with detection limit under 10 ng/l in drinking water samples. Performance data for the method such as recovery and precision are also reported.

Chromatography, High Pressure Liquid↗
PubMed2000

Soluble proteins from chemosensory organs of Eurycantha calcarata (Insects, Phasmatodea).

Three related nucleotide sequences, encoding mature proteins of 108-113 amino acids, have been obtained from antennal cDNA of the Phasmid Eurycantha calcarata. Among these, one is also expressed in the tarsi as demonstrated by N-terminal sequence and mass spectrometric analyses of protein samples isolated from both organs. PCR experiments performed with specific primers, showed that this species is also expressed in the mouth organs and in the cuticle, while the other two are antennal specific. All three isoforms are similar to Drosophila OS-D and other proteins reported in several insect orders, but one of them is significantly different from the other two. The best conserved elements are the N-terminal region and the four cysteine residues. Accurate ESMS measurements indicated that all cysteines are involved in two disulphide bonds and ruled out the occurrence of additional post-translational modifications. Polyclonal antibodies, raised against the purified protein, did not react with proteins of the same class expressed in another Phasmid species, Carausius morosus, and in the orthopteran Schistocerca gregaria, nor did antibodies against these proteins recognise those of E. calcarata.

Amino Acid Sequence↗
PubMed1998

Determination of arylphenoxypropionic herbicides in water by liquid chromatography-electrospray mass spectrometry.

A very sensitive and specific analytical procedure for determining arylphenoxypropionic herbicides in aqueous environmental samples, using pneumatically assisted electrospray (ESI) liquid chromatography-mass spectrometry (LC-MS) is presented. Arylphenoxypropionic acids are a new class of herbicides used for the selective removal of most grass species from any nongrass crop. These herbicides are commercialized as herbicide esters. It has been shown that the ester derivatives undergo fast hydrolysis in the presence of vegetable tissues and soil bacteria, yielding the corresponding free acid. The analytical procedure involves passing 1l of surface or ground water and 2l of drinking-water samples, through a 0.5-g graphitized carbon black (GCB) extraction cartridge. A conventional 4.6-mm I.D. reversed-phase LC C18, operating with a 1 ml/min mobile phase flow-rate, was used for chromatographing the analytes. A flow of 200 microliters/min of the column effluent was diverted to the ESI source. The ESI source was operated in positive-ion mode for neutral pesticides and in negative-ion mode for acid pesticides. For ion-signal optimization, the effect of the concentration of the acid in the mobile phase on the response of the ESI-MS detector was investigated. By evaluating the specificity and sensitivity of the method, the effects of varying the orifice plate voltage on the production of the diagnostic fragment and the response of the MS detector were also investigated. For the analyte considered, the response of the mass detector was linearly related to the amount of the analyte injected between 1 and 200 ng. In all cases, recoveries of the analytes were better than 91%. The limit of detection (signal-to-noise ratio = 3) of the method for the pesticides considered in drinking water samples was estimated to be about 3-10 ng/l.

Chromatography, High Pressure Liquid↗
PubMed1998

Subtypes of odorant-binding proteins--heterologous expression and ligand binding.

Odorant-binding proteins (OBP) in the mucus of the olfactory epithelium are thought to transfer the hydrophobic odorous compounds through the aqueous barrier towards the chemo-sensory cells. To evaluate their binding properties, two distinct OBP subtypes of the rat were expressed as N-terminal His-tagged fusion proteins in Escherichia coli, thus allowing an efficient purification. Based on gel chromatography and CD spectroscopy analysis the recombinant OBP subtypes seem to share several structural features with other members of the lipocalin family. Approaches to elucidate whether heterologous expressed OBPs interact with odorous compounds revealed that OBP1 specifically binds 2-[3H]-isobutyl-3-methoxypyrazine whereas OBP2 did not shown any specific binding to this compound. In contrast, the chromophore 1-anilinonaphthalene 8-sulfonic acid (1,8-ANS) specifically interacted with OBP2 but not with OBP1. Displacement experiments monitored by the relative fluorescence intensity revealed that fatty acids with appropriate chain length act as efficient competitors. Some odorous compounds, notably lilial (p-tert-butyl-alpha-methyl dihydrocinnamic aldehyde) and citralva (3,7-dimethyl-2,6-octadienenitrile), also displaced efficiently the chromophore, whereas pyrazine derivatives including 2-isobutyl-3-methoxypyrazine and other odorants did not. These results indicate that rat OBPs have distinct ligand specificities.

Anilino Naphthalenesulfonates↗
PubMed1998

Development of a method based on liquid chromatography-electrospray mass spectrometry for analyzing imidazolinone herbicides in environmental water at part-per-trillion levels.

An evaluation was made of the feasibility of using reversed-phase liquid chromatography-mass spectrometry with an electrospray interface (LC-ESI-MS) to measure traces of imidazolinone herbicides in different natural water samples. The imidazolinones are a significant new class of low-use-rate, reduced-environmental-risk herbicides for the protection of a wide variety of agricultural commodities. The procedure used involved passing 0.5, 1, 2 1 of river, ground and drinking water samples, respectively, through a 0.5 g graphitized carbon black (GCB) extraction cartridge. Analytes were eluted from the GCB surface by 8 ml of a methylene chloride-methanol (80:20, v/v) solution acidified with formic acid, 25 mM. Recovery was higher than 89% irrespective of the aqueous matrix in which the analytes were dissolved. A conventional 4.6 mm I.D. reversed-phase LC C18 column operating with a mobile phase flow-rate of 1 ml/min was used to chromatograph the analytes. A flow of 50 microliters/min of the column effluent was diverted to the ESI source. The effects of acid concentration on ESI-MS detector response in the mobile phase were investigated. The effects on the production of diagnostic fragments produced by varying the orifice plate voltage and the response of the MS detector were also evaluated. For the analyte considered, the response of the mass detector was linearly related to the amount of analyte injected between 1 and 50 ng. The limit of detection (signal-to-noise ratio = 3) of the method for the pesticides considered in drinking water samples was estimated to be about 2-5 ng/l.

Chromatography, Liquid↗
PubMed1998

Lipocalins of boar salivary glands binding odours and pheromones.

Large amounts of an odorant-binding protein have been isolated from submaxillary glands of mature male pig. This polypeptide molecule is sex-specific, being absent in females. On electrophoretic gels under denaturing conditions it migrated as a broad band with an apparent molecular mass of around 20 kDa. Electrospray mass spectrometry revealed the presence of three main components, whose mass differences are not interpretable as result of any common post-translational modifications, indicating the presence of distinct polypeptide chains. N-terminal Edman degradation yielded a single sequence of 29 amino acids. It includes the lipocalin signature (-G-X-W-) and shows clear homology with a subclass of odorant-binding proteins present in mouse saliva, nasal mucus and urine. The purified protein still retained small ligands tightly bound; among them 5alpha-androst-16-en-3-one and 5alpha-androst-16-en-3alpha-ol, both known sex pheromones for the pig, were identified. The protein also binds 2-isobutyl-3-methoxypyrazine, a good ligand for most odorant-binding proteins, with a dissociation constant of 5 microM.

Amino Acid Sequence↗
PubMed1998

Amino acid sequence, post-translational modifications, binding and labelling of porcine odorant-binding protein.

An odorant-binding protein, migrating in SDS-PAGE with an apparent molecular weight of 22 kDa and an isoelectric point of 4.2, has been purified from pig nasal mucosa. Its complete amino acid sequence was determined by a combination of mass spectrometry and Edman degradation procedures. The protein consists of a single polypeptide chain of 157 amino acids, presenting at the N-terminus a pyroglutamic acid residue. The two cysteine residues, occurring in the primary structure at positions 63 and 155, are involved in an intramolecular disulphide bridge. Sequence comparison with other lipocalins revealed a good similarity with bovine odorant-binding protein, the only member of this class which does not contain disulphide bonds and of which the three-dimensional structure recently has been resolved. Nine out of the 1 6 residues lining the binding pocket in bovine OBP are conserved in the porcine protein, suggesting structural similarities in this region of the molecule. The synthesis of a fluorescent photoaffinity labelling agent and of two tin-containing thymol analogues is also described. These compounds together with other ligands were able to bind the protein as revealed by competitive binding experiments.

Amino Acid Sequence↗
PubMed1997

Identification of HHV-8 DNA in the skin lesions of Kaposi's sarcoma in an immunosuppressed patient with bullous pemphigoid.

Kaposi's sarcoma rarely occurs as an opportunistic tumor in iatrogenically immunosuppressed patients. We describe the clinical presentation, treatment of Kaposi's sarcoma skin lesions in an immunosuppressed patient with bullous pemphigoid. Using the polymerase chain reaction, HHV-8 DNA was detected in two separate Kaposi's sarcoma lesions but not in control tissues. The amplified DNA fragments derived from our patient's Kaposi's sarcoma skin lesions contained unique point mutations that distinguished the virus isolated from Kaposi's sarcoma lesions derived from other patients. This is the first demonstration that HHV-8 DNA is associated with Kaposi's sarcoma skin lesions in an HIV-negative, immunosuppressed patient with bullous pemphigoid. HHV-8 is probably a common latent herpesvirus that is activated by immunosuppressive therapy in genetically predisposed patients and may be involved in the pathogenesis of Kaposi's sarcoma.

Aged↗
PubMed1997

Neuropeptide Y release from cultured hippocampal neurons: stimulation by glutamate acting at N-methyl-D-aspartate and AMPA receptors.

L-Glutamate, N-methyl-D-aspartate, DL-alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) and kainate increased the release of neuropeptide Y-like immunoreactivity from primary cultures of rat hippocampal neurons incubated in Mg2+(1.2 mM)-containing medium. The neuropeptide Y-like immunoreactivity released by 100 microM glutamate was mainly accounted for by neuropeptide Y (1-36), but consisted in part (about 20%) of peptide YY. The effect of 100 microM glutamate on neuropeptide Y-like immunoreactivity release was largely (about 70%) prevented by the N-methyl-D-aspartate receptor antagonist dizocilpine maleate (10 microM), while the remainder (about 30%) was sensitive to the AMPA/ kainate receptor antagonist 6-nitro-7-sulphamoylbenzo(f)quinoxaline-2-3-dione (10 microM). The AMPA(100 microM)-evoked release of neuropeptide Y-like immunoreactivity was strongly antagonized by 6-nitro-7-sulphamoylbenzo(f)quinoxaline-2-3-dione and by 1-aminophenyl-4-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine, but it was in part (15-20%) sensitive to dizocilpine. The releases of neuropeptide Y-like immunoreactivity elicited by glutamate, N-methyl-D-aspartate, AMPA and kainate were all strongly Ca(2+)-dependent. Tetrodotoxin (1 microM) abrogated the N-methyl-D-aspartate-evoked release and partly inhibited the release caused by glutamate, but did not modify significantly AMPA- or kainate-evoked release. Removal of Mg2+ from the medium caused increase of neuropeptide Y-like immunoreactivity release, an effect prevented by dizocilpine maleate or 7-Cl-kynurenate. Cyclothiazide (10 microM), a drug known to prevent AMPA receptor desensitization, enhanced the neuropeptide Y-like immunoreactivity release elicited by 100 microM AMPA, but not that caused by 100 microM kainate. However, when used at a lower concentration (50 microM), kainate elicited a response that was potentiated significantly by cyclothiazide. It is concluded that glutamate can stimulate Ca(2+)-dependent release of neuropeptide Y from hippocampal neurons mainly through N-methyl-D-aspartate receptors and, less so, by activating cyclothiazide-sensitive receptors of the AMPA-preferring type.

Animals↗
PubMed1997

Treatment of acute respiratory failure secondary to pulmonary oedema with bi-level positive airway pressure by nasal mask.

We report the successful outcome of first-line intervention of noninvasive positive pressure ventilation (NPPV) in four patients, three of whom had hypercapnic acute respiratory failure (ARF) and one hypoxaemic ARF, secondary to pulmonary oedema. The clinical condition showed rapid improvement and the NPPV, performed together with aggressive medical treatment, was effective in decreasing the respiratory frequency, and in correcting gas exchange abnormalities within the first 3 h. The average duration of nasal mask ventilation was 11 h (range 6-15 h). The patients were weaned, following ARF, by removing the ventilator whenever inspiratory positive airway pressure (IPAP) was 5 cmH2O. NPPV was applied, by nasal mask, using a bi-level positive airway pressure (BiPAP) delivering pressure support ventilation (PSV). We conclude that application of noninvasive positive pressure ventilation may be effective in correcting gas exchange abnormalities, in relieving respiratory distress and, perhaps, in avoiding endotracheal intubation in selected patients with acute respiratory failure secondary to reversible medical condition such as pulmonary oedema.

Aged↗