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1.
Appl Opt ; 61(31): 9256-9261, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36607061

RESUMO

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.
Appl Opt ; 57(20): 5844-5851, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30118056

RESUMO

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.

3.
Appl Opt ; 57(28): 8373, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30461791

RESUMO

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

4.
Rev Sci Instrum ; 90(9): 094501, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31575245

RESUMO

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.

5.
Curr Med Chem ; 15(18): 1827-39, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18691041

RESUMO

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.


Assuntos
Amina Oxidase (contendo Cobre)/antagonistas & inibidores , Amina Oxidase (contendo Cobre)/química , Monoaminoxidase/química , Semicarbazidas/química , Doença de Alzheimer/tratamento farmacológico , Amina Oxidase (contendo Cobre)/metabolismo , Aminas/química , Animais , Sangue/metabolismo , Bovinos , Moléculas de Adesão Celular/metabolismo , Diabetes Mellitus/tratamento farmacológico , Humanos , Concentração Inibidora 50 , Plasma/metabolismo , Ratos , Especificidade por Substrato
6.
J Chromatogr A ; 1101(1-2): 198-203, 2006 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-16246349

RESUMO

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.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Pirazóis/isolamento & purificação , Amilose/análogos & derivados , Benzoatos , Celulose/análogos & derivados , Cromatografia Líquida de Alta Pressão/instrumentação , Fenilcarbamatos , Solventes , Estereoisomerismo
7.
Rev Sci Instrum ; 86(2): 026106, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25725899

RESUMO

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.

8.
Farmaco ; 59(12): 945-52, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15598429

RESUMO

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.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Semicarbazidas/síntese química , Semicarbazidas/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Testes de Sensibilidade Microbiana/métodos
9.
Farmaco ; 47(1): 99-110, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1616581

RESUMO

This paper reports the synthesis of a novel class of macrocyclic tetraesters containing 1,3-butandiol sub-units by reacting the stannolan derivative of the diol with diacyl chloride. The structure of the possible isomers was assigned by spectroscopic data and comparison with samples otherwise prepared. Preliminary screening revealed that these compounds have low antimicrobial activity, although it is higher than that of the starting diol.


Assuntos
Anti-Infecciosos/síntese química , Butileno Glicóis/síntese química , Antibacterianos , Antifúngicos/síntese química , Antifúngicos/farmacologia , Butileno Glicóis/farmacologia , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos
10.
Farmaco ; 55(2): 93-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10782378

RESUMO

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.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Tiossemicarbazonas/síntese química , Tiossemicarbazonas/farmacologia , Anti-Infecciosos/química , Química Farmacêutica , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Tiossemicarbazonas/química
11.
Farmaco ; 56(8): 549-54, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11601639

RESUMO

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.


Assuntos
Antraquinonas/síntese química , Anti-Infecciosos/síntese química , Antraquinonas/farmacologia , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
12.
Farmaco ; 58(9): 951-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-13679191

RESUMO

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.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Tiossemicarbazonas/farmacologia , Antibacterianos/química , Antifúngicos/química , Desenho de Fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Tiossemicarbazonas/química , Leveduras/efeitos dos fármacos
13.
Farmaco ; 52(1): 55-9, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9181683

RESUMO

This paper reports the synthesis and the study of a few new diastereomeric arylmethylcycloalkylamines, tested as potential dopamine receptor active agents. New procedures for the stereospecific synthesis of the arylmethylcycloalkylamines were successfully experimented. All the considered compounds did not show any appreciable dopamine receptor activity.


Assuntos
Aminas/síntese química , Cicloparafinas/síntese química , Dopaminérgicos/síntese química , Aminas/farmacologia , Animais , Cicloparafinas/farmacologia , Dopaminérgicos/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Ratos , Receptores Dopaminérgicos/efeitos dos fármacos , Espectrofotometria Infravermelho
14.
Farmaco ; 53(10-11): 698-708, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10205857

RESUMO

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.


Assuntos
Inibidores de Ciclo-Oxigenase/síntese química , Pirazóis/síntese química , Inibidores de Ciclo-Oxigenase/química , Humanos , Espectroscopia de Ressonância Magnética , Pirazóis/química , Estereoisomerismo
15.
Farmaco ; 57(10): 809-17, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12420876

RESUMO

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.


Assuntos
Anti-Infecciosos/farmacologia , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologia , Animais , Antibacterianos , Anti-Infecciosos/síntese química , Chlorocebus aethiops , Fungos/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade , Células Vero/efeitos dos fármacos
16.
Eur J Med Chem ; 45(10): 4490-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20702005

RESUMO

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.


Assuntos
Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacologia , Monoaminoxidase/metabolismo , Pirazóis/química , Pirazóis/farmacologia , Tioamidas/química , Tioamidas/farmacologia , Animais , Linhagem Celular , Humanos , Insetos , Modelos Moleculares , Inibidores da Monoaminoxidase/síntese química , Ligação Proteica , Pirazóis/síntese química , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Tioamidas/síntese química
17.
Eur J Cancer ; 44(13): 1829-34, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18640031

RESUMO

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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Adulto , Idoso , Ácidos Borônicos/administração & dosagem , Ácidos Borônicos/efeitos adversos , Bortezomib , Feminino , Humanos , Infusões Intravenosas , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Pirazinas/administração & dosagem , Pirazinas/efeitos adversos , Resultado do Tratamento
18.
Opt Lett ; 30(1): 32-4, 2005 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-15648628

RESUMO

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.

19.
Rapid Commun Mass Spectrom ; 12(20): 1569-73, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9796539

RESUMO

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.


Assuntos
Queijo/análise , Indústria de Laticínios , Contaminação de Alimentos/análise , Proteínas do Leite/análise , Animais , Calibragem , Bovinos , Feminino , Ovinos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
20.
Mol Biol Rep ; 25(2): 73-86, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9540068

RESUMO

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.


Assuntos
Cromatina/química , Difração de Raios X/métodos , Animais , Bovinos , Cromatina/isolamento & purificação , Simulação por Computador , Modelos Biológicos , Espalhamento de Radiação , Cloreto de Sódio , Timo
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