Paolo Ferrario - Academia.edu (original) (raw)

Papers by Paolo Ferrario

Research paper thumbnail of Correlation between carotid intima-media thickness, ADMA and coronary flow reserve in rheumatoid arthtritis

Research paper thumbnail of Preliminary Observation on the Cytotoxic Activity of New Chlorophyllin Derivative RCD on Human Tumour Cell Lines In Vitro

Anticancer Research, 2019

Background: Chlorophyllin is used in traditional Chinese medicine because of its anticancer prope... more Background: Chlorophyllin is used in traditional Chinese medicine because of its anticancer properties. This article describes the preparation and cytotoxic activity of a reduced chlorophyllin derivative (RCD) on tumour cell lines. Materials and Methods: RCD was prepared by reducing chlorophyllin with lithium aluminium hydride, and its solubility in the alkaline and organic phases are different from that of the parent compound chlorophyllin. Results: RCD also has different chromatographic behaviour from chlorophyllin on thin-layer chromatography and highpressure liquid chromatography, and excitation and emission spectra. RCD has cytotoxic activity against ZR-75, MCF-7 and HT-29, human tumour cell lines. A clonogenic assay showed that the growth of tumour colonies on soft agar was reduced by RCD in a dose-dependent manner. Conclusion: RCD is a novel compound exhibiting anticancer activity.

Research paper thumbnail of Effects of interleukin-1� and interleukin-2 on amino acids levels in mouse cortex and hippocampus

Research paper thumbnail of Amino Acid Levelsin the Brain of Rats with Peripheral Nerve Constriction or Section

Pain Research and Management, 1997

BACKGROUND: Both excitatory and inhibitory amino acids modulate central neuronal activity followi... more BACKGROUND: Both excitatory and inhibitory amino acids modulate central neuronal activity following peripheral nerve tissue injury.OBJECTIVE: To establish whether mononeuropathy induced by chronic constriction injury or by sectioning of the sciatic nerve affects neurotransmitter amino acid levels in the rat brain areas.METHODS: Glutamine, glutamic acid, gamma-aminobutyric acid (GABA) and aspartic acid in the hindbrain, midbrain and hypothalamus of rats were measured by high performance liquid chromatography 14 days after surgery.RESULTS: After monolateral nerve ligation an increase in glutamine and a decrease in GABA levels in all brain areas were observed, with no side preference. The section of the sciatic nerve did not cause any modification in amino acid levels.CONCLUSIONS: The results allow one to differentiate more clearly classic models of mononeuropathy from a biochemical point of view. Moreover, results indicate that continuous neuronal stimulation induced by nerve constric...

Research paper thumbnail of Asymmetric dimethylarginine (ADMA): an endogenous inhibitor of nitric oxide synthase and a novel cardiovascular risk molecule

Medical science monitor : international medical journal of experimental and clinical research, 2009

Asymmetric dimethylarginine (ADMA), a methyl derivate of the amino acid arginine, is produced by ... more Asymmetric dimethylarginine (ADMA), a methyl derivate of the amino acid arginine, is produced by the physiological degradation of methylated proteins. ADMA is the major endogenous inhibitor of nitric oxide synthase (NOS), the enzyme which synthesizes nitric oxide (NO), a molecule endowed with important anti-atherosclerotic properties. Increased plasma ADMA concentrations cause impaired NO synthesis leading to endothelial dysfunction and atherosclerotic vascular disease. Increased plasma ADMA levels mainly occur following inhibition of the enzyme responsible for ADMA catabolism, dimethylarginine dimethylaminohydrolase (DDAH), by oxidative stress triggered by several cardiovascular risk factors. This paper reviews the effects on cardiovascular function produced by ADMA administration to experimental animals and humans. In addition, a number of clinical conditions associated with increased plasma ADMA concentrations are considered. Then the growing body of literature indicating that pl...

Research paper thumbnail of In vivo metabolism and kinetics of99mTc-HMPAO

European Journal of Nuclear Medicine, 1990

Under suitable conditions we prove the wellposedness of small time-varied delay equations and the... more Under suitable conditions we prove the wellposedness of small time-varied delay equations and then establish the robust stability for such systems on the phase space of continuous vector-valued functions.

Research paper thumbnail of Determination of diclofenac in plasma and synovial fluid by high-performance liquid chromatography with electrochemical detection

Journal of Chromatography B: Biomedical Sciences and Applications, 1989

sodium, sodmm o-(2,6-dlchlorophenyl )ammophenylacetate (Voltaren 1, 1s a potent non-steroidal ant... more sodium, sodmm o-(2,6-dlchlorophenyl )ammophenylacetate (Voltaren 1, 1s a potent non-steroidal anti-inflammatory and analgesic drug, which has been used successfully for several years m the treatment of rheumatic deseases [l-3] This compound 1s metabolized m animals and humans to the corresponding mono-and dlhydroxy and conjugated derlvatlves [4,5] Several methods have been described for its determmatlon m body flulds, includmg gas chromatography with electron-capture detection [ 6,7], gas chromatography-mass spectrometry and high-performance llquld chromatography (HPLC) with VV detection [lo-21

Research paper thumbnail of Synthesis and biodistribution of an 123I labelled flunitrazepam derivative: a potential in vivo tracer for benzodiazepine receptors

International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1988

A method for the synthesis of no-carrier-added of 7-[t23I]iodo-l,3-dihydro-5-(2-fluorophenyl)-l-m... more A method for the synthesis of no-carrier-added of 7-[t23I]iodo-l,3-dihydro-5-(2-fluorophenyl)-l-methyl-2H-1,4-. benzodiazepine-2-one with a radiochemical yield of 25-30% has been developed. This benzodiazepine was prepared by reaction of [123I]iodide with the corresponding piperidyltriazene in acid medium and the reaction has been optimized for solvent, time and temperature. The triazene was synthesized by reduction of flunitrazepam to the amine, diazotisation and coupling with piperidine. Biodistribution studies of this radioligand in rats showed a maximum brain uptake of 0.35% of the injected dose at 15min, which decline to 0.02% at 120 min.

Research paper thumbnail of Toxicological and teratological studies in rats after exposure to pulsed magnetic fields

Bioelectrochemistry and Bioenergetics, 1985

The risk effects of low-intensity pulsed magnetic fields on rat fetal development and on the adul... more The risk effects of low-intensity pulsed magnetic fields on rat fetal development and on the adult rat were examined. Pregnant female rats were exposed daily to the field (50 Hz and 58 G) during organogenesis. Fetuses were tested for number, size, weight and malformations. Adult rats (150-185 g) were exposed daily for 28 days to the field, then sacrificed. General conditions, behaviour and increase in weight were observed. Furthermore, hematological, hematochemical and urine determinations were carried out. The main organs were weighed and evaluated histologically. No significant differences were noted in both experiments. These results may suggest that the effects of low-intensity pulsed magnetic fields are not detectable under the conditions used here.

Research paper thumbnail of The effect of alternating magnetic fields on experimental inflammation in the rat

Bioelectrochemistry and Bioenergetics, 1985

There is a large interest in the use of pulsed electromagnetic fields in inflammatory pathologies... more There is a large interest in the use of pulsed electromagnetic fields in inflammatory pathologies . The anti-inflammatory activity of a pulsed magnetic field has been tested in rats . As experimental models, the carragenin acute inflammation and chronic adjuvant arthritis were applied . A significant decrease of edema volume was noted in the acute model. On the contrary, no changes in inflammation rate were observed in the chronic model, even if a significant improvement of performance was shown .

Research paper thumbnail of Determination of diclofenac and its metabolites in plasma and cerebrospinal fluid by high-performance liquid chromatography with electrochemical detection

Journal of Chromatography B: Biomedical Sciences and Applications, 1991

A reversed-phase high-performance liquid chromatographic method with electrochemical detection fo... more A reversed-phase high-performance liquid chromatographic method with electrochemical detection for the quantitation of diclofenac and metabolites in plasma and cerebrospinal fluid has been developed. Pirprofen is employed as internal standard. Samples are extracted with C18 solid-phase extraction columns and eluted with methanol. Oxidation potentials for detection were established by constructing voltammograms for each compound. In the concentration range found in human studies, the intra-day coefficients of variation were always less than 6%. The procedure allows the simultaneous determination of diclofenac and its four major metabolites with very low detection limits (less than 1 ng/ml), which were sufficient even for kinetic studies in cerebrospinal fluid.

Research paper thumbnail of In vivo and in vitro Effects of Bromelain on PGE<sub>2</sub> and SP Concentrations in the Inflammatory Exudate in Rats

Pharmacology, 2002

The effects of bromelain were examined in rats with subcutaneous carrageenin-induced inflammation... more The effects of bromelain were examined in rats with subcutaneous carrageenin-induced inflammation. After oral in vivo administration, bromelain (10 and 20 mg/kg p.o.) induced a significant decrease of both PGE(2) and substance P concentrations in the exudate. When added to the inflammatory exudate in vitro, the drug (25, 50, 100 microg/ml) did not affect PGE(2) concentrations and induced an increase in the substance P levels. Our data indicate that bromelain reduces the production of two key mediators of inflammation. This effect does not seem to be related to a direct action of the drug on PGE(2) and SP released in the exudate in response to the inflammatory stimulus.

Research paper thumbnail of GM-CSF affects hypothalamic neurotransmitter levels in mice

NeuroReport, 1997

We studied the effects of granulocyte-macrophage colony stimulating factor (GM-CSF) on the brain ... more We studied the effects of granulocyte-macrophage colony stimulating factor (GM-CSF) on the brain levels of several neurotransmitters in mice. Administration of GM-CSF (5.0 and 10 microg, i.p.) significantly reduced the hypothalamic levels of glutamine, glutamic acid, GABA and aspartic acid. GM-CSF (5.0 microg, i.p.) also induced a significant reduction of norepinephrine and serotonin levels in the hypothalamus, without affecting dopamine levels. The hippocampal levels of neurotransmitters were not modified by GM-CSF administration. The peripheral administration of a specific interleukin-1 receptor antagonist (IL-1ra, 50 microg, i.p.) blocked the effects of GM-CSF. These results confirm our previous behavioural data suggesting that GM-CSF is able to exert neuromodulatory actions.

Research paper thumbnail of Effects of the bisphosphonate ibandronate on hyperalgesia, substance P, and cytokine levels in a rat model of persistent inflammatory pain

European Journal of Pain, 2008

The anti-inflammatory and analgesic properties of different bisphosphonates have been demonstrate... more The anti-inflammatory and analgesic properties of different bisphosphonates have been demonstrated in both animal and human studies. Ibandronate is a third-generation bisphosphonate effective in managing different types of bone pain. In this study we investigated its effects in a standard pre-clinical model of inflammatory pain. We evaluated the effects of a single injection of different doses (0.5, 1.0, and 2.0 mg/kg i.p.) of ibandronate on inflammatory oedema and cutaneous hyperalgesia produced by the intraplantar injection of complete Freund’s adjuvant (CFA) in the rat hind-paw. In addition, we measured the effects of this drug (1.0 mg/kg i.p.) on hind-paw levels of different pro-inflammatory mediators (PGE-2, SP, TNF-α, and IL-1β). We also measured the levels of SP protein and of its mRNA in the ipsilateral dorsal root ganglia (DRG). Ibandronate proved able to reduce the inflammatory oedema, the hyperalgesia to mechanical stimulation, and the levels of SP in the inflamed tissue as measured 3 and 7 days following CFA-injection. This drug significantly reduced the levels of TNF-α and IL-1β only on day 7. On the other hand, the levels of PGE-2 in the inflamed hind-paw were unaffected by the administration of this bisphosphonate. Finally, ibandronate blocked the overexpression of SP mRNA in DRG induced by CFA-injection in the hind-paw.These data help to complete the pharmacodynamic profile of ibandronate, while also suggesting an involvement of several inflammatory mediators, with special reference to substance P, in the analgesic action of this bisphosphonate.

Research paper thumbnail of Effects of tramadol on synovial fluid concentrations of substance P and interleukin-6 in patients with knee osteoarthritis: comparison with paracetamol

International Immunopharmacology, 2003

Both the analgesic drugs tramadol and paracetamol are widely used for the symptomatic therapy of ... more Both the analgesic drugs tramadol and paracetamol are widely used for the symptomatic therapy of osteoarthritis (OA). The aim of this double-blind, randomised study in patients with knee OA was to compare their effects on synovial fluid concentrations of interleukin (IL)-6 and substance P (SP). Moreover, we evaluated plasma and synovial fluid concentrations of tramadol and its active metabolite (O-desmethyl-tramadol, M1) after oral treatment with this drug. Twenty patients were enrolled. A group of 10 patients received tramadol (50 mg three times a day), and another group of 10 patients were treated with paracetamol (500 mg three times a day) for 7 days. Both drugs significantly reduced the intensity of joint pain. The synovial fluid concentrations of SP were significantly reduced only by the treatment with tramadol. In this group of patients, IL-6 synovial fluid concentrations were slightly, but not significantly, decreased. Paracetamol did not significantly change the synovial fluid concentrations of SP and IL-6. After oral administration, a considerable amount of tramadol was measurable in synovial fluid. Both in plasma and synovial fluid the concentrations of M1 were markedly lower than those of tramadol, with a T/M1 ratio of 14.7±4.6 and 9.3±3.9, respectively. These data demonstrate that the activity of tramadol may involve the modulation of inflammatory mediators. Moreover, they indicate that after oral treatment with tramadol, both the parent drug and its active metabolite can penetrate into synovial fluid.

Research paper thumbnail of L-arginine, asymmetric dimethylarginine, and symmetric dimethylarginine in plasma and synovial fluid of patients with knee osteoarthritis

Medical Science Monitor, 2013

The aim of this study was to investigate the involvement of the nitric oxide (NO) pathway in oste... more The aim of this study was to investigate the involvement of the nitric oxide (NO) pathway in osteoarthritis (OA).

Research paper thumbnail of Interleukin6 affects scopolamine-induced amnesia, but not brain amino acid levels in mice

Neuroreport, 1997

We have previously shown that, after peripheral administration, different cytokines affect cognit... more We have previously shown that, after peripheral administration, different cytokines affect cognitive functions in mice. In this study, we evaluated the effects of mouse interleukin-6 (IL-6) on the classical behavioural test of scopolamine-induced amnesia for a passive avoidance response in the mouse. Pretraining i.p. administration of this cytokine (0.125 and 0.5 microgram/mouse) significantly reduced the amnesic action of the muscarinic receptor antagonist. As it is well known that brain amino acids are deeply involved in the modulation of cognitive processes we measured the levels of glutamine, aspartic acid, glutamic acid and GABA in the hippocampus and hypothalamus of mice treated with IL-6. At both doses which affected the cognitive functions, this cytokine had no effect on brain levels of measured amino acids. Neither nociceptive thresholds to a thermal stimulus, nor spontaneous locomotor activity were modified by the acute administration of IL-6 (0.5 microgram/mouse). Our data confirm previous observations indicating that peripheral administration of cytokines affects some, but not other brain functions and suggest the involvement of IL-6 in the central modifications induced by the immune activation.

Research paper thumbnail of Analysis of pirprofen in cerebrospinal fluid, plasma, and synovial fluid by high-performance liquid chromatography with electrochemical detection

Journal of Pharmaceutical Sciences, 1989

We describe a high-performance liquid chromatographic method, using electrochemical detection, fo... more We describe a high-performance liquid chromatographic method, using electrochemical detection, for the determination of pirprofen in cerebrospinal fluid (CSF), plasma, and synovial fluid (SF). A C-18 column with a mobile phase containing acetonitrile acetate:phosphate buffer (pH 3.0) was employed. Samples were added with phosphoric acid, then extracted into dichloromethane, evaporated, and injected into the chromatograph. A detection potential of +0.85 V was applied on the basis of current-potential curves. Good linearity was found for each fluid in the expected range of therapeutic concentrations. The detection limit was 0.1 ng/mL for CSF, and 1 ng/mL for plasma and SF, with a recovery >96% and intraday coefficient of variation <5% in all cases. The main advantages of this method include high specificity and sensitivity which allow the analysis of CSF and the use of small volumes of plasma and SF. The application of the method for the analysis of plasma and SFsamples and the kinetic profile in CSF are shown.

Research paper thumbnail of Simultaneous determination of nimesulide and hydroxynimesulide in rat plasma, cerebrospinal fluid and brain by liquid chromatography using solid-phase extraction

Journal of Chromatography B, 2003

A liquid chromatographic method with UV detection for the quantification of nimesulide (N) and hy... more A liquid chromatographic method with UV detection for the quantification of nimesulide (N) and hydroxynimesulide (M1) in rat plasma, cerebrospinal fluid (CSF) and brain tissue is reported. Plasma samples (250 microl) and brain homogenates added with the right amount of the internal standard (I.S., 2&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-(cyclohexyloxy)-4&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-nitrophenyl methanesulphonanilide, NS398) are extracted on C(18) disposable cartridges by solid-phase extraction (SPE), while CSF samples are analyzed without any extraction. The separation is performed at room temperature on a Waters Symmetry C(18) 3.5 microm (150x4.6 mm I.D.) column with acetonitrile-sodium citrate buffer pH 3.00 (53:47, v/v) as mobile phase, at a flow-rate of 1.1 ml/min and detection at 240 nm. The retention times are 3.3, 6.0 and 9.9 min for M1, N and I.S., respectively. The lower limits of quantitation for either nimesulide and M1 are 25 ng/ml for plasma, 20 ng/ml for CSF and 25 ng/g for brain tissue. The calibration curves are linear up to 10,000 ng/ml for plasma, 5000 ng/ml for CSF and 5000 ng/g for brain tissue. This new assay can be applied to the study of the role of nimesulide in the modulation of neuroinflammatory processes.

Research paper thumbnail of Asymmetric dimethylarginine (ADMA) induces vascular endothelium impairment and aggravates post-ischemic ventricular dysfunction in rats

European Journal of Pharmacology, 2007

Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide (NO) inhibitor recognized as an ... more Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide (NO) inhibitor recognized as an independent risk factor for endothelial dysfunction and coronary heart diseases. This study investigated whether ADMA (10 mg/kg day for 14 days) affected endothelial function and aggravated post-ischemic ventricular dysfunction in the perfused rat heart. Systolic blood pressure and heart rate, plasma levels of ADMA and nitrite/nitrate were measured in vehicle-and ADMA-treated rats. Perfused hearts were submitted to global ischemia-reperfusion and vascular endothelial dysfunction was examined with angiotensin II in coronary vessels and aortic rings. Endothelial NO synthase (eNOS) and angiotensinconverting enzyme (ACE) mRNA expression in aortic and cardiac tissues were measured. ADMA-treated rats had higher systolic blood pressure (1.3-fold, P b 0.01) and slower heart rate (16%, P b 0.05) than controls. Plasma ADMA rose (1.9-fold, P b 0.01) and nitrite/nitrate concentration decreased 59% (P b 0.001). Ventricular contraction (stiffness) increased significantly, with worsening of post-ischemic ventricular dysfunction. In preparations from ADMA-treated rats the coronary vasculature's response to angiotensin II was almost doubled (P b 0.01) and the maximal vasorelaxant effect of acetylcholine in aortic rings was significantly lower than in preparations from vehicle-treated rats. In cardiac and aortic tissues eNOS mRNA and ACE mRNA levels were similar in controls and ADMA-treated rats. The increased plasma levels of ADMA presumably cause endothelial dysfunction because of a deficiency in NO production, which also appears involved in the aggravation of myocardial ischemiareperfusion injury.

Research paper thumbnail of Correlation between carotid intima-media thickness, ADMA and coronary flow reserve in rheumatoid arthtritis

Research paper thumbnail of Preliminary Observation on the Cytotoxic Activity of New Chlorophyllin Derivative RCD on Human Tumour Cell Lines In Vitro

Anticancer Research, 2019

Background: Chlorophyllin is used in traditional Chinese medicine because of its anticancer prope... more Background: Chlorophyllin is used in traditional Chinese medicine because of its anticancer properties. This article describes the preparation and cytotoxic activity of a reduced chlorophyllin derivative (RCD) on tumour cell lines. Materials and Methods: RCD was prepared by reducing chlorophyllin with lithium aluminium hydride, and its solubility in the alkaline and organic phases are different from that of the parent compound chlorophyllin. Results: RCD also has different chromatographic behaviour from chlorophyllin on thin-layer chromatography and highpressure liquid chromatography, and excitation and emission spectra. RCD has cytotoxic activity against ZR-75, MCF-7 and HT-29, human tumour cell lines. A clonogenic assay showed that the growth of tumour colonies on soft agar was reduced by RCD in a dose-dependent manner. Conclusion: RCD is a novel compound exhibiting anticancer activity.

Research paper thumbnail of Effects of interleukin-1� and interleukin-2 on amino acids levels in mouse cortex and hippocampus

Research paper thumbnail of Amino Acid Levelsin the Brain of Rats with Peripheral Nerve Constriction or Section

Pain Research and Management, 1997

BACKGROUND: Both excitatory and inhibitory amino acids modulate central neuronal activity followi... more BACKGROUND: Both excitatory and inhibitory amino acids modulate central neuronal activity following peripheral nerve tissue injury.OBJECTIVE: To establish whether mononeuropathy induced by chronic constriction injury or by sectioning of the sciatic nerve affects neurotransmitter amino acid levels in the rat brain areas.METHODS: Glutamine, glutamic acid, gamma-aminobutyric acid (GABA) and aspartic acid in the hindbrain, midbrain and hypothalamus of rats were measured by high performance liquid chromatography 14 days after surgery.RESULTS: After monolateral nerve ligation an increase in glutamine and a decrease in GABA levels in all brain areas were observed, with no side preference. The section of the sciatic nerve did not cause any modification in amino acid levels.CONCLUSIONS: The results allow one to differentiate more clearly classic models of mononeuropathy from a biochemical point of view. Moreover, results indicate that continuous neuronal stimulation induced by nerve constric...

Research paper thumbnail of Asymmetric dimethylarginine (ADMA): an endogenous inhibitor of nitric oxide synthase and a novel cardiovascular risk molecule

Medical science monitor : international medical journal of experimental and clinical research, 2009

Asymmetric dimethylarginine (ADMA), a methyl derivate of the amino acid arginine, is produced by ... more Asymmetric dimethylarginine (ADMA), a methyl derivate of the amino acid arginine, is produced by the physiological degradation of methylated proteins. ADMA is the major endogenous inhibitor of nitric oxide synthase (NOS), the enzyme which synthesizes nitric oxide (NO), a molecule endowed with important anti-atherosclerotic properties. Increased plasma ADMA concentrations cause impaired NO synthesis leading to endothelial dysfunction and atherosclerotic vascular disease. Increased plasma ADMA levels mainly occur following inhibition of the enzyme responsible for ADMA catabolism, dimethylarginine dimethylaminohydrolase (DDAH), by oxidative stress triggered by several cardiovascular risk factors. This paper reviews the effects on cardiovascular function produced by ADMA administration to experimental animals and humans. In addition, a number of clinical conditions associated with increased plasma ADMA concentrations are considered. Then the growing body of literature indicating that pl...

Research paper thumbnail of In vivo metabolism and kinetics of99mTc-HMPAO

European Journal of Nuclear Medicine, 1990

Under suitable conditions we prove the wellposedness of small time-varied delay equations and the... more Under suitable conditions we prove the wellposedness of small time-varied delay equations and then establish the robust stability for such systems on the phase space of continuous vector-valued functions.

Research paper thumbnail of Determination of diclofenac in plasma and synovial fluid by high-performance liquid chromatography with electrochemical detection

Journal of Chromatography B: Biomedical Sciences and Applications, 1989

sodium, sodmm o-(2,6-dlchlorophenyl )ammophenylacetate (Voltaren 1, 1s a potent non-steroidal ant... more sodium, sodmm o-(2,6-dlchlorophenyl )ammophenylacetate (Voltaren 1, 1s a potent non-steroidal anti-inflammatory and analgesic drug, which has been used successfully for several years m the treatment of rheumatic deseases [l-3] This compound 1s metabolized m animals and humans to the corresponding mono-and dlhydroxy and conjugated derlvatlves [4,5] Several methods have been described for its determmatlon m body flulds, includmg gas chromatography with electron-capture detection [ 6,7], gas chromatography-mass spectrometry and high-performance llquld chromatography (HPLC) with VV detection [lo-21

Research paper thumbnail of Synthesis and biodistribution of an 123I labelled flunitrazepam derivative: a potential in vivo tracer for benzodiazepine receptors

International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1988

A method for the synthesis of no-carrier-added of 7-[t23I]iodo-l,3-dihydro-5-(2-fluorophenyl)-l-m... more A method for the synthesis of no-carrier-added of 7-[t23I]iodo-l,3-dihydro-5-(2-fluorophenyl)-l-methyl-2H-1,4-. benzodiazepine-2-one with a radiochemical yield of 25-30% has been developed. This benzodiazepine was prepared by reaction of [123I]iodide with the corresponding piperidyltriazene in acid medium and the reaction has been optimized for solvent, time and temperature. The triazene was synthesized by reduction of flunitrazepam to the amine, diazotisation and coupling with piperidine. Biodistribution studies of this radioligand in rats showed a maximum brain uptake of 0.35% of the injected dose at 15min, which decline to 0.02% at 120 min.

Research paper thumbnail of Toxicological and teratological studies in rats after exposure to pulsed magnetic fields

Bioelectrochemistry and Bioenergetics, 1985

The risk effects of low-intensity pulsed magnetic fields on rat fetal development and on the adul... more The risk effects of low-intensity pulsed magnetic fields on rat fetal development and on the adult rat were examined. Pregnant female rats were exposed daily to the field (50 Hz and 58 G) during organogenesis. Fetuses were tested for number, size, weight and malformations. Adult rats (150-185 g) were exposed daily for 28 days to the field, then sacrificed. General conditions, behaviour and increase in weight were observed. Furthermore, hematological, hematochemical and urine determinations were carried out. The main organs were weighed and evaluated histologically. No significant differences were noted in both experiments. These results may suggest that the effects of low-intensity pulsed magnetic fields are not detectable under the conditions used here.

Research paper thumbnail of The effect of alternating magnetic fields on experimental inflammation in the rat

Bioelectrochemistry and Bioenergetics, 1985

There is a large interest in the use of pulsed electromagnetic fields in inflammatory pathologies... more There is a large interest in the use of pulsed electromagnetic fields in inflammatory pathologies . The anti-inflammatory activity of a pulsed magnetic field has been tested in rats . As experimental models, the carragenin acute inflammation and chronic adjuvant arthritis were applied . A significant decrease of edema volume was noted in the acute model. On the contrary, no changes in inflammation rate were observed in the chronic model, even if a significant improvement of performance was shown .

Research paper thumbnail of Determination of diclofenac and its metabolites in plasma and cerebrospinal fluid by high-performance liquid chromatography with electrochemical detection

Journal of Chromatography B: Biomedical Sciences and Applications, 1991

A reversed-phase high-performance liquid chromatographic method with electrochemical detection fo... more A reversed-phase high-performance liquid chromatographic method with electrochemical detection for the quantitation of diclofenac and metabolites in plasma and cerebrospinal fluid has been developed. Pirprofen is employed as internal standard. Samples are extracted with C18 solid-phase extraction columns and eluted with methanol. Oxidation potentials for detection were established by constructing voltammograms for each compound. In the concentration range found in human studies, the intra-day coefficients of variation were always less than 6%. The procedure allows the simultaneous determination of diclofenac and its four major metabolites with very low detection limits (less than 1 ng/ml), which were sufficient even for kinetic studies in cerebrospinal fluid.

Research paper thumbnail of In vivo and in vitro Effects of Bromelain on PGE<sub>2</sub> and SP Concentrations in the Inflammatory Exudate in Rats

Pharmacology, 2002

The effects of bromelain were examined in rats with subcutaneous carrageenin-induced inflammation... more The effects of bromelain were examined in rats with subcutaneous carrageenin-induced inflammation. After oral in vivo administration, bromelain (10 and 20 mg/kg p.o.) induced a significant decrease of both PGE(2) and substance P concentrations in the exudate. When added to the inflammatory exudate in vitro, the drug (25, 50, 100 microg/ml) did not affect PGE(2) concentrations and induced an increase in the substance P levels. Our data indicate that bromelain reduces the production of two key mediators of inflammation. This effect does not seem to be related to a direct action of the drug on PGE(2) and SP released in the exudate in response to the inflammatory stimulus.

Research paper thumbnail of GM-CSF affects hypothalamic neurotransmitter levels in mice

NeuroReport, 1997

We studied the effects of granulocyte-macrophage colony stimulating factor (GM-CSF) on the brain ... more We studied the effects of granulocyte-macrophage colony stimulating factor (GM-CSF) on the brain levels of several neurotransmitters in mice. Administration of GM-CSF (5.0 and 10 microg, i.p.) significantly reduced the hypothalamic levels of glutamine, glutamic acid, GABA and aspartic acid. GM-CSF (5.0 microg, i.p.) also induced a significant reduction of norepinephrine and serotonin levels in the hypothalamus, without affecting dopamine levels. The hippocampal levels of neurotransmitters were not modified by GM-CSF administration. The peripheral administration of a specific interleukin-1 receptor antagonist (IL-1ra, 50 microg, i.p.) blocked the effects of GM-CSF. These results confirm our previous behavioural data suggesting that GM-CSF is able to exert neuromodulatory actions.

Research paper thumbnail of Effects of the bisphosphonate ibandronate on hyperalgesia, substance P, and cytokine levels in a rat model of persistent inflammatory pain

European Journal of Pain, 2008

The anti-inflammatory and analgesic properties of different bisphosphonates have been demonstrate... more The anti-inflammatory and analgesic properties of different bisphosphonates have been demonstrated in both animal and human studies. Ibandronate is a third-generation bisphosphonate effective in managing different types of bone pain. In this study we investigated its effects in a standard pre-clinical model of inflammatory pain. We evaluated the effects of a single injection of different doses (0.5, 1.0, and 2.0 mg/kg i.p.) of ibandronate on inflammatory oedema and cutaneous hyperalgesia produced by the intraplantar injection of complete Freund’s adjuvant (CFA) in the rat hind-paw. In addition, we measured the effects of this drug (1.0 mg/kg i.p.) on hind-paw levels of different pro-inflammatory mediators (PGE-2, SP, TNF-α, and IL-1β). We also measured the levels of SP protein and of its mRNA in the ipsilateral dorsal root ganglia (DRG). Ibandronate proved able to reduce the inflammatory oedema, the hyperalgesia to mechanical stimulation, and the levels of SP in the inflamed tissue as measured 3 and 7 days following CFA-injection. This drug significantly reduced the levels of TNF-α and IL-1β only on day 7. On the other hand, the levels of PGE-2 in the inflamed hind-paw were unaffected by the administration of this bisphosphonate. Finally, ibandronate blocked the overexpression of SP mRNA in DRG induced by CFA-injection in the hind-paw.These data help to complete the pharmacodynamic profile of ibandronate, while also suggesting an involvement of several inflammatory mediators, with special reference to substance P, in the analgesic action of this bisphosphonate.

Research paper thumbnail of Effects of tramadol on synovial fluid concentrations of substance P and interleukin-6 in patients with knee osteoarthritis: comparison with paracetamol

International Immunopharmacology, 2003

Both the analgesic drugs tramadol and paracetamol are widely used for the symptomatic therapy of ... more Both the analgesic drugs tramadol and paracetamol are widely used for the symptomatic therapy of osteoarthritis (OA). The aim of this double-blind, randomised study in patients with knee OA was to compare their effects on synovial fluid concentrations of interleukin (IL)-6 and substance P (SP). Moreover, we evaluated plasma and synovial fluid concentrations of tramadol and its active metabolite (O-desmethyl-tramadol, M1) after oral treatment with this drug. Twenty patients were enrolled. A group of 10 patients received tramadol (50 mg three times a day), and another group of 10 patients were treated with paracetamol (500 mg three times a day) for 7 days. Both drugs significantly reduced the intensity of joint pain. The synovial fluid concentrations of SP were significantly reduced only by the treatment with tramadol. In this group of patients, IL-6 synovial fluid concentrations were slightly, but not significantly, decreased. Paracetamol did not significantly change the synovial fluid concentrations of SP and IL-6. After oral administration, a considerable amount of tramadol was measurable in synovial fluid. Both in plasma and synovial fluid the concentrations of M1 were markedly lower than those of tramadol, with a T/M1 ratio of 14.7±4.6 and 9.3±3.9, respectively. These data demonstrate that the activity of tramadol may involve the modulation of inflammatory mediators. Moreover, they indicate that after oral treatment with tramadol, both the parent drug and its active metabolite can penetrate into synovial fluid.

Research paper thumbnail of L-arginine, asymmetric dimethylarginine, and symmetric dimethylarginine in plasma and synovial fluid of patients with knee osteoarthritis

Medical Science Monitor, 2013

The aim of this study was to investigate the involvement of the nitric oxide (NO) pathway in oste... more The aim of this study was to investigate the involvement of the nitric oxide (NO) pathway in osteoarthritis (OA).

Research paper thumbnail of Interleukin6 affects scopolamine-induced amnesia, but not brain amino acid levels in mice

Neuroreport, 1997

We have previously shown that, after peripheral administration, different cytokines affect cognit... more We have previously shown that, after peripheral administration, different cytokines affect cognitive functions in mice. In this study, we evaluated the effects of mouse interleukin-6 (IL-6) on the classical behavioural test of scopolamine-induced amnesia for a passive avoidance response in the mouse. Pretraining i.p. administration of this cytokine (0.125 and 0.5 microgram/mouse) significantly reduced the amnesic action of the muscarinic receptor antagonist. As it is well known that brain amino acids are deeply involved in the modulation of cognitive processes we measured the levels of glutamine, aspartic acid, glutamic acid and GABA in the hippocampus and hypothalamus of mice treated with IL-6. At both doses which affected the cognitive functions, this cytokine had no effect on brain levels of measured amino acids. Neither nociceptive thresholds to a thermal stimulus, nor spontaneous locomotor activity were modified by the acute administration of IL-6 (0.5 microgram/mouse). Our data confirm previous observations indicating that peripheral administration of cytokines affects some, but not other brain functions and suggest the involvement of IL-6 in the central modifications induced by the immune activation.

Research paper thumbnail of Analysis of pirprofen in cerebrospinal fluid, plasma, and synovial fluid by high-performance liquid chromatography with electrochemical detection

Journal of Pharmaceutical Sciences, 1989

We describe a high-performance liquid chromatographic method, using electrochemical detection, fo... more We describe a high-performance liquid chromatographic method, using electrochemical detection, for the determination of pirprofen in cerebrospinal fluid (CSF), plasma, and synovial fluid (SF). A C-18 column with a mobile phase containing acetonitrile acetate:phosphate buffer (pH 3.0) was employed. Samples were added with phosphoric acid, then extracted into dichloromethane, evaporated, and injected into the chromatograph. A detection potential of +0.85 V was applied on the basis of current-potential curves. Good linearity was found for each fluid in the expected range of therapeutic concentrations. The detection limit was 0.1 ng/mL for CSF, and 1 ng/mL for plasma and SF, with a recovery >96% and intraday coefficient of variation <5% in all cases. The main advantages of this method include high specificity and sensitivity which allow the analysis of CSF and the use of small volumes of plasma and SF. The application of the method for the analysis of plasma and SFsamples and the kinetic profile in CSF are shown.

Research paper thumbnail of Simultaneous determination of nimesulide and hydroxynimesulide in rat plasma, cerebrospinal fluid and brain by liquid chromatography using solid-phase extraction

Journal of Chromatography B, 2003

A liquid chromatographic method with UV detection for the quantification of nimesulide (N) and hy... more A liquid chromatographic method with UV detection for the quantification of nimesulide (N) and hydroxynimesulide (M1) in rat plasma, cerebrospinal fluid (CSF) and brain tissue is reported. Plasma samples (250 microl) and brain homogenates added with the right amount of the internal standard (I.S., 2&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-(cyclohexyloxy)-4&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-nitrophenyl methanesulphonanilide, NS398) are extracted on C(18) disposable cartridges by solid-phase extraction (SPE), while CSF samples are analyzed without any extraction. The separation is performed at room temperature on a Waters Symmetry C(18) 3.5 microm (150x4.6 mm I.D.) column with acetonitrile-sodium citrate buffer pH 3.00 (53:47, v/v) as mobile phase, at a flow-rate of 1.1 ml/min and detection at 240 nm. The retention times are 3.3, 6.0 and 9.9 min for M1, N and I.S., respectively. The lower limits of quantitation for either nimesulide and M1 are 25 ng/ml for plasma, 20 ng/ml for CSF and 25 ng/g for brain tissue. The calibration curves are linear up to 10,000 ng/ml for plasma, 5000 ng/ml for CSF and 5000 ng/g for brain tissue. This new assay can be applied to the study of the role of nimesulide in the modulation of neuroinflammatory processes.

Research paper thumbnail of Asymmetric dimethylarginine (ADMA) induces vascular endothelium impairment and aggravates post-ischemic ventricular dysfunction in rats

European Journal of Pharmacology, 2007

Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide (NO) inhibitor recognized as an ... more Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide (NO) inhibitor recognized as an independent risk factor for endothelial dysfunction and coronary heart diseases. This study investigated whether ADMA (10 mg/kg day for 14 days) affected endothelial function and aggravated post-ischemic ventricular dysfunction in the perfused rat heart. Systolic blood pressure and heart rate, plasma levels of ADMA and nitrite/nitrate were measured in vehicle-and ADMA-treated rats. Perfused hearts were submitted to global ischemia-reperfusion and vascular endothelial dysfunction was examined with angiotensin II in coronary vessels and aortic rings. Endothelial NO synthase (eNOS) and angiotensinconverting enzyme (ACE) mRNA expression in aortic and cardiac tissues were measured. ADMA-treated rats had higher systolic blood pressure (1.3-fold, P b 0.01) and slower heart rate (16%, P b 0.05) than controls. Plasma ADMA rose (1.9-fold, P b 0.01) and nitrite/nitrate concentration decreased 59% (P b 0.001). Ventricular contraction (stiffness) increased significantly, with worsening of post-ischemic ventricular dysfunction. In preparations from ADMA-treated rats the coronary vasculature's response to angiotensin II was almost doubled (P b 0.01) and the maximal vasorelaxant effect of acetylcholine in aortic rings was significantly lower than in preparations from vehicle-treated rats. In cardiac and aortic tissues eNOS mRNA and ACE mRNA levels were similar in controls and ADMA-treated rats. The increased plasma levels of ADMA presumably cause endothelial dysfunction because of a deficiency in NO production, which also appears involved in the aggravation of myocardial ischemiareperfusion injury.