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1.
Appl Opt ; 61(31): 9256-9261, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36607061

RESUMEN

We demonstrate that a middle sized ring laser gyroscope (RLG) can be a very sensitive and robust instrument for rotational seismology, even if it operates in a quite noisy environment. The RLG has a square cavity, 1.60×1.60m 2, and it lies in a plane orthogonal to the Earth's rotational axis. The Fabry-Perot optical cavities along the diagonals of the square were accessed, and their lengths were locked to a reference laser. Through a quite simple locking circuit, we were able to keep the sensor fully operative for 14 days. We verified that the prototype properties are compatible with the seismic requirements. The obtained long term stability is of the order of 3 nanorad/s, and the short term sensitivity is close to 2n a n o r a d/s⋅H z -1/2. These results are limited only by the noisy environment; our laboratory is located in a building downtown.

2.
Rev Sci Instrum ; 90(9): 094501, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31575245

RESUMEN

We present the realization, installation, and first results of a three-axial Fiber Bragg Grating (FBG) strain sensor prototype. This sensor has been developed in the framework of the Mediterranean supersite volcanoes (http://www.med-suv.eu, 2013) project and, in particular, with the aim at contributing to the study and monitoring of Etna volcano. The FBG sensor was installed in the facilities of the Serra La Nave Astrophysical Observatory (Catania, Italy) about 7 km south-west from the summit craters, at an elevation of about 1740 m. The three-axial device showed a dynamic range of some hundreds of microstrains with microstrain resolution (submicrostrain concerning the vertical component). That is a good trade-off among performances, cost, and power consumption. The sensor structure and its read-out system are innovative in their assembly and offers practical advantages in comparison with traditional strain meters. As a demonstration of the performances of our device, the data of about 28 months of operation are presented together with the records of some local, regional, and teleseismic events. The sensor along the vertical axis showed to be the best performing one, having a power spectral density of about -90 dB re. 1ε2/Hz around one day period.

3.
Appl Opt ; 57(28): 8373, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30461791

RESUMEN

This publisher's note identifies a figure error in Appl. Opt.57, 5844 (2018)APOPAI0003-693510.1364/AO.57.005844.

4.
Appl Opt ; 57(20): 5844-5851, 2018 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-30118056

RESUMEN

Gyroscopes IN GEneral Relativity (GINGER) is a proposed experiment with the aim of measuring in a ground laboratory the gravitoelectric and gravitomagnetic effects foreseen by general relativity through an array of ring laser gyroscopes. GINGERINO is a square ring-laser prototype that has been built to investigate the level of noise inside the Gran Sasso underground laboratory. GINGERINO has shown the advantage of the underground location. Now it provides suitable data for geophysics and seismology. Since May 2017, it has continuously acquired data. The analysis of the first 90 days shows that the duty cycle is higher than 95%, and the quantum shot noise limit is of the order of 10-10(rad/s)/Hz. It is located in a seismically active area, and it recorded part of the central Italy earthquakes. Its high sensitivity in the frequency band of fraction of hertz makes it suitable for seismology studies. The main purpose of the present analysis is to investigate the long-term response of the apparatus. Simple and fast routines to suppress the disturbances coming from the laser have been developed. The Allan deviation of the raw data reaches some 10-6 after about 106 s of integration time, while the processed data show an improvement of 1 order of magnitude. Disturbances at the daily time scale are present in the processed data, and the expected signal induced by polar motion and solid Earth tides is covered by those disturbances.

5.
Rev Sci Instrum ; 86(2): 026106, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25725899

RESUMEN

The influence of fiber Bragg grating diameter when measuring strain is investigated and quantified. Two fiber Bragg gratings with bare cladding diameter of 125 µm and 80 µm are produced by excimer laser irradiation through a phase mask, and are used to simultaneously monitor the Bragg wavelength shift due to the strain produced by the solidification of a photo-curable resin during light exposure. It is found that the ratio of the measured strains in the two fiber Bragg gratings is close to the inverse ratio of the fiber's cladding diameter. These results represent a direct simultaneous comparison between 125 µm and 80 µm diameter fiber Bragg grating strain sensors, and demonstrate the feasibility of strain measurements in photo-curable resins using bare 80 µm cladding diameter fiber Bragg gratings with an increased sensitivity and spatial resolution compared with standard 125 µm diameter fiber Bragg gratings.

6.
Eur J Med Chem ; 45(10): 4490-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20702005

RESUMEN

Some differently substituted 3-aryl-4,5-dihydropyrazoles-1-carbothioamides have been synthesised with the aim to investigate their monoamine oxidase inhibitory activity. The chemical structures of the compounds have been characterized by means of their IR, (1)H NMR, (13)C NMR spectroscopic data and elemental analyses. All the active compounds showed a selective activity towards the B isoform of the enzyme, regardless of the substitution on the heterocyclic ring. The inhibition of the enzymatic activity was measured on human recombinant MAO isoforms, expressed in baculovirus infected BTI insect cells. Docking experiments were carried out with the aim to rationalize the mechanism of inhibition of the most active and selective compound.


Asunto(s)
Inhibidores de la Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/farmacología , Monoaminooxidasa/metabolismo , Pirazoles/química , Pirazoles/farmacología , Tioamidas/química , Tioamidas/farmacología , Animales , Línea Celular , Humanos , Insectos , Modelos Moleculares , Inhibidores de la Monoaminooxidasa/síntesis química , Unión Proteica , Pirazoles/síntesis química , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/metabolismo , Relación Estructura-Actividad , Tioamidas/síntesis química
7.
Curr Med Chem ; 15(18): 1827-39, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18691041

RESUMEN

SSAO/VAP-1 is not only involved in the metabolism of biogenic and xenobiotic primary amines and in the production of metabolites with cytotoxic effects or certain physiological actions, but also plays a role, for example, as an adhesion molecule, in leukocyte trafficking, in regulating glucose uptake and in adipocyte homeostasis. Interest in the enzyme has been stimulated by the findings that the activities of the SSAOs are altered (mostly increased) in various human disorders, including diabetes, congestive heart failure, liver cirrhosis, Alzheimer's disease and several inflammatory diseases, although the underlying causes are often unknown. On the basis of their insulin-mimicking effect, SSAO substrates are possibly capable of ameliorating metabolic changes in diabetes, while SSAO inhibitors (somewhat of a contradiction) are of potential benefit in preventing diabetes complications, atherosclerosis and oxidative stress contributing to several disorders or modulating inflammation, and hence may be of substantial therapeutic value. Great efforts have been made to develop novel compounds which may lead to future drugs useful in therapy, based on their effects on SSAO/VAP-1, and some of the results relating to novel substrates and inhibitors are surveyed in the present review.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/antagonistas & inhibidores , Amina Oxidasa (conteniendo Cobre)/química , Monoaminooxidasa/química , Semicarbacidas/química , Enfermedad de Alzheimer/tratamiento farmacológico , Amina Oxidasa (conteniendo Cobre)/metabolismo , Aminas/química , Animales , Sangre/metabolismo , Bovinos , Moléculas de Adhesión Celular/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Humanos , Concentración 50 Inhibidora , Plasma/metabolismo , Ratas , Especificidad por Sustrato
8.
Eur J Cancer ; 44(13): 1829-34, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18640031

RESUMEN

BACKGROUND: The combination of a proteasome inhibitor with a taxane has potential clinical synergism that prompted a clinical test. PATIENTS AND METHODS: The maximum tolerated dose (MTD) and recommended dose (RD) of intravenous (i.v.) Bortezomib (B) (days 1, 4, 8, 11) and i.v. Paclitaxel (PTX) (days 1, 8) every 3 weeks was evaluated in patients with advanced solid tumours. The RD was tested in patients with breast, ovarian and prostate cancer. At the RD, microarray analysis of transcriptional profiles was carried out before and after the first dosing in peripheral blood mononuclear cells (PBMC). RESULTS: Thirty-one patients were enrolled and 22 were treated at the RD that corresponded to B 1.3mg/m(2) and PTX 100mg/m(2). The main toxicity was cumulative peripheral neuropathy (76% of patients; grade 3-4 in 9%) that required treatment discontinuation in six patients, followed by diarrhoea (55%) and fatigue (41%). Nine partial responses (30%) were observed (three breast cancer, four ovary, two prostate patients). Significant (p<0.05) and consistent changes (>70% of patients) in transcriptome were observed. CONCLUSIONS: The incidence of peripheral neuropathy and the anti-tumour activity comparable to that of single-agent PTX do not support further development of this regimen.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias de la Próstata/tratamiento farmacológico , Adulto , Anciano , Ácidos Borónicos/administración & dosificación , Ácidos Borónicos/efectos adversos , Bortezomib , Femenino , Humanos , Infusiones Intravenosas , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Pirazinas/administración & dosificación , Pirazinas/efectos adversos , Resultado del Tratamiento
9.
J Chromatogr A ; 1101(1-2): 198-203, 2006 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-16246349

RESUMEN

The direct HPLC enantioseparation of five pairs of new chiral pyrazole derivatives on coated cellulose- and amylose-based chiral stationary phases (Chiralpak AD, Chiralcel OJ and Chiralcel OJ-RH) and new immobilised amylose-based Chiralpak IA CSP was performed. Very high enantioselectivity factor (alpha) values were achieved in polar organic and reversed-phase conditions by using OJ-RH as CSP. Chiralpak IA exhibited an excellent chiral resolving ability in normal-phase mode and it allowed the enantioseparation of analytes investigated with resolution factors (Rs) >20. Due to its bonded nature, it was successfully employed at analytical and semipreparative scale in combination with normal-phase eluents containing "non-standards" solvents such as acetone.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Pirazoles/aislamiento & purificación , Amilosa/análogos & derivados , Benzoatos , Celulosa/análogos & derivados , Cromatografía Líquida de Alta Presión/instrumentación , Fenilcarbamatos , Solventes , Estereoisomerismo
10.
Opt Lett ; 30(1): 32-4, 2005 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-15648628

RESUMEN

We demonstrate the possibility of using a femtosecond laser to measure with high accuracy the frequency of a far-infrared (FIR) monochromatic source, such as an optically pumped molecular laser, by generating in a suitable mixer a signal in the radio-frequency region at the frequency difference between n steps of a femtosecond comb and the FIR source. All the couples of modes lying a distance of n steps from one another contribute coherently to the heterodyne signal. The technique has been tested up to 670 GHz.

11.
Farmaco ; 59(12): 945-52, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15598429

RESUMEN

The synthesis of some aroylisothiosemicarbazides was accomplished and their biological activity against bacteria, fungi, and mycobacteria was investigated. Different synthetic pathways were followed according to the kind of substituents that were introduced on both the aroyl ring and the sulfur atom. Anti-bacterial activity was measured against Staphylococcus aureus, S. epidermidis, Streptococcus agalactiae and S. faecalis, Escherichia coli, and Salmonella typhi, while antifungal activity was evaluated against C. albicans. Two species, Mycobacterium tuberculosis H37RV and Mycobacterium avium ATCC19421, were employed to evaluate antimycobacterial activity.


Asunto(s)
Antibacterianos/síntesis química , Antibacterianos/farmacología , Semicarbacidas/síntesis química , Semicarbacidas/farmacología , Evaluación Preclínica de Medicamentos/métodos , Pruebas de Sensibilidad Microbiana/métodos
12.
Farmaco ; 58(9): 951-9, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-13679191

RESUMEN

Several arylideneisothiosemicarbazones and arylidenehydrazothiazoles have been synthesised to obtain new antimicrobial agents. Their activity against both bacteria and fungi has been tested and some interesting informations about their biological activity have been obtained.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Tiosemicarbazonas/farmacología , Antibacterianos/química , Antifúngicos/química , Diseño de Fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad , Tiosemicarbazonas/química , Levaduras/efectos de los fármacos
13.
Farmaco ; 57(10): 809-17, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12420876

RESUMEN

It is known that some derivatives of both thiourea and thiosemicarbazide exhibit potent anti-microbial activity. In order to investigate the effects on the biological properties of structural modifications of such structures, we have synthesised and studied some arylidenisothiosemicarbazones. In this paper we report on the synthesis and structure-activity relationships of some isothiosemicarbazones, where the arylidene group has been replaced with a cycloalkyl group and the sulfur atom has been either differently substituted or enclosed in a thiazole ring.


Asunto(s)
Antiinfecciosos/farmacología , Tiosemicarbazonas/química , Tiosemicarbazonas/farmacología , Animales , Antibacterianos , Antiinfecciosos/síntesis química , Chlorocebus aethiops , Hongos/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Pruebas de Sensibilidad Microbiana , Espectrometría de Masa por Ionización de Electrospray , Relación Estructura-Actividad , Células Vero/efectos de los fármacos
14.
Farmaco ; 56(8): 549-54, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11601639

RESUMEN

9,10-Anthracenedione derivatives are known to exhibit a quite potent anticancer activity. It has also been reported that these compounds can be effectively employed in both antibacterial and antitrypanosomal therapy. Anthraquinones also exhibit some undesirable side effects, like cardiotoxicity. So many interactions seem to demonstrate that 9,10-anthracenediones strongly interact with a number of biological sites. In this paper we wish to report on the synthesis and the pharmaceutical activity of some newly synthesised derivatives containing the anthraquinone pharmacophore.


Asunto(s)
Antraquinonas/síntesis química , Antiinfecciosos/síntesis química , Antraquinonas/farmacología , Antiinfecciosos/farmacología , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad
15.
Rapid Commun Mass Spectrom ; 15(12): 1000-10, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11400210

RESUMEN

A set of aminoalkoxy-substituted, differently annullated furocoumarins, differing in the position of the aminoalkoxy chain and in the unsaturation level of the fused ring, has been subjected to electron impact and electrospray ionisation (ESI) experiments. In order to achieve a distinct characterisation of isomeric compounds, which partially failed under electron impact conditions, collision-induced dissociation experiments were performed on protonated molecules. The breakdown curves obtained by varying the tickle voltage on an ion trap ESI instrument led to the desired characterisation.


Asunto(s)
Furocumarinas/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Benceno/química , Furocumarinas/química , Isomerismo
16.
Farmaco ; 55(2): 93-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10782378

RESUMEN

Arylidenimidazoles bearing a thioethereal function in the position 2 of the imidazole ring show good antimicrobial activity. We now report on the synthesis and the biological properties of some novel arylidenisothiosemicarbazones, structurally related to the arylideneiminoimidazoles of which they can be considered the linear precursors. Particular attention has been put on the influence of structural modifications on the biological activity.


Asunto(s)
Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Antifúngicos/síntesis química , Antifúngicos/farmacología , Tiosemicarbazonas/síntesis química , Tiosemicarbazonas/farmacología , Antiinfecciosos/química , Química Farmacéutica , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad , Tiosemicarbazonas/química
17.
Rapid Commun Mass Spectrom ; 12(20): 1569-73, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9796539

RESUMEN

Ewe milk and ewe cheese samples were analysed by matrix-assisted laser desorption/ionization mass spectrometry and their protein profiles were compared with those obtained from bovine milk and bovine cheeses. Various mixtures of bovine and ewe cheeses in different weight ratios were analysed, leading to a reproducible calibration curve, which has been successfully employed in determining the percentage of bovine milk fraudulently added to ewe milk in the production of marketed ewe cheese.


Asunto(s)
Queso/análisis , Industria Lechera , Contaminación de Alimentos/análisis , Proteínas de la Leche/análisis , Animales , Calibración , Bovinos , Femenino , Ovinos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
18.
Mol Biol Rep ; 25(2): 73-86, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9540068

RESUMEN

This work investigates the structure of native calf thymus chromatin as a function of fiber length and isolation procedures by using X-ray small angle scattering technique. Two methods of chromatin isolation have been compared in order to better understand the differences reported by various authors in terms of chromatin high order structure. In addition to these experimental results the effects of shearing have also been studied. In order to explain the differences among these chromatin preparations we built several models of chromatin fibers (represented as a chain of spherical subunits) assuming increasing level of condensation at increasing salt concentrations. For all these fiber models the corresponding theoretical X-ray scattering curves have been calculated and these results have been used to explain the influence of fiber length on the scattering profiles of chromatin. The comparison between experimental and theoretical curves confirms that the high molecular weight chromatin-DNA prepared by hypotonic swelling of nuclei (without enzymatic digestion) displays a partially folded structure even at low ionic strength, whereas the low molecular weight chromatin-DNA prepared by a brief nuclease digestion appears very weakly folded at the same ionic conditions.


Asunto(s)
Cromatina/química , Difracción de Rayos X/métodos , Animales , Bovinos , Cromatina/aislamiento & purificación , Simulación por Computador , Modelos Biológicos , Dispersión de Radiación , Cloruro de Sodio , Timo
19.
J Agric Food Chem ; 46(2): 762-765, 1998 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-10554311

RESUMEN

The influence of epicuticular waxes extracted from different fruits on the photodegradation of pirimicarb (I) in the solid phase was studied. Waxes were extracted with CHCl(3) and CHCl(3)/CH(3)OH from nectarines (N), oranges (O(R)), and mandarin oranges (M). All of the waxes affect the qualitative behavior of the photodegradation of I: the formation of photoproducts N-formylpirimicarb (II) and demethylpirimicarb (III) was hindered. This influence was found to be independent of the light sources (sunlight or lamp > 290 nm) and of the solvents employed in the extraction of the waxes. The photodegradation rate (K(obs)) of I was reduced to a different extent by the presence of waxes, from N and O, and was increased from M (irrespective of the extraction solvent). The photodegradation rates of II and III were both reduced by all waxes, M included. The waxes extracted with CHCl(3)/CH(3)OH show a higher inhibition effect on K(obs) than those with CHCl(3). The scales of rate reduction were similar under sunlight and artificial light. Inhibition of the photodegradation rate does not correlate with UV absorbance of waxes or with their content on the surface of the fruits.

20.
Farmaco ; 53(10-11): 698-708, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-10205857

RESUMEN

In this study some cycloalkyl-3-(N-substituted carbamoyl)-1-phenylpyrazoles have been synthesized in order to screen their capability to inhibit human cyclooxygenase. The synthetic pathway is based on the well known property of nitrilimines to undergo 1,3-dipolar cycloaddition reactions. The structures of all the synthesized compounds have been elucidated by means of both analytical and spectroscopic methods.


Asunto(s)
Inhibidores de la Ciclooxigenasa/síntesis química , Pirazoles/síntesis química , Inhibidores de la Ciclooxigenasa/química , Humanos , Espectroscopía de Resonancia Magnética , Pirazoles/química , Estereoisomerismo
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