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1.
Sci Rep ; 11(1): 14510, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267277

RESUMO

We present a 3D model of the main crustal boundaries beneath the Campanian region and the onshore and offshore surrounding areas, based on high-resolution potential field data. Our main objective is the definition of the main structural interfaces in the whole Campanian region from gravity and magnetic data, thanks to their ability to define them on a regional and continuous way. The complex morphology of the Mesozoic carbonate platform, which is fundamental to constrain the top of geothermal reservoir, was reconstructed by inverting the vertical gradient of gravity. We assumed local information from seismic models and boreholes to improve the model. We modeled the deep crustal structures by spectral analysis of Bouguer gravity and magnetic data. The inferred depth estimates indicate a shallow crystalline basement below the Tyrrhenian crust and the Apulian foreland and a significant depression beneath the Bradanic foredeep. The map of the Moho boundary shows a NE-SE verging trough below the Southern Apennine chain and two pronounced uplifts beneath the foreland and the Tyrrhenian crust. We also estimated the depth to the magnetic bottom, showing a thick magnetic crust below the mountain chain and shallow depths where the crustal heat flow is high. The models were compared with seismic sections along selected profiles; a good agreement was observed, despite of some inherent lower resolution for the gravity modelling from spectral methods. The regional covering and the continuity of our estimated crustal interfaces make it a new and valid reference for further geological, geophysical and geothermal studies, especially in areas such as northern and eastern Campania, where there is an incomplete geophysical and geological information.

2.
Eur Phys J Plus ; 136(4): 472, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968561

RESUMO

The LABEC laboratory, the INFN ion beam laboratory of nuclear techniques for environment and cultural heritage, located in the Scientific and Technological Campus of the University of Florence in Sesto Fiorentino, started its operational activities in 2004, after INFN decided in 2001 to provide our applied nuclear physics group with a large laboratory dedicated to applications of accelerator-related analytical techniques, based on a new 3 MV Tandetron accelerator. The new accelerator greatly improved the performance of existing Ion Beam Analysis (IBA) applications (for which we were using since the 1980s an old single-ended Van de Graaff accelerator) and in addition allowed to start a novel activity of Accelerator Mass Spectrometry (AMS), in particular for 14C dating. Switching between IBA and AMS operation became very easy and fast, which allowed us high flexibility in programming the activities, mainly focused on studies of cultural heritage and atmospheric aerosol composition, but including also applications to biology, geology, material science and forensics, ion implantation, tests of radiation damage to components, detector performance tests and low-energy nuclear physics. This paper describes the facilities presently available in the LABEC laboratory, their technical features and some success stories of recent applications.

3.
Sci Rep ; 10(1): 16019, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994504

RESUMO

We aim at modeling the main crustal and thermal interfaces of Sicily (Italy), a key area for understanding the geological complexity at the collisional boundary between the African and European plates. To this end, we analyze the gravity and magnetic fields, integrated with information from well logs, geology, heat flow, and seismic data. In order to make the most accurate description of the crustal structure of the area, we modeled with different methodologies the carbonate and crystalline top surfaces, as well as the Moho and the Curie isotherm surface. The reconstruction of the carbonate platform is achieved using a nonlinear 3D method constrained by the available seismic and borehole data. The crystalline top, the Curie, and the Moho are instead estimated by spectral analysis of both gravity and magnetic data. The results show a complex carbonate basement and a deep crystalline crust in central Sicily, with a prominent uplift beneath the Hyblean Plateau. Maps of the Moho and the Curie isotherm surface define a variable thermal and structural setting of Sicily, with very thin crust in the southern and eastern sectors, where high heat flow is found, and deep and cold crust below the Caltanissetta Basin.

4.
Sci Rep ; 8(1): 13420, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30194356

RESUMO

Volcanic phenomena are currently monitored by the detection of physical and chemical observations. Generally, the ground deformation field is the most relevant shallow expression of the geometric and physical parameters variations in the magmatic reservoir. In this study, we propose a novel method for the direct estimation of the geometric parameters of sources responsible for volcanic ground deformation detected via the DInSAR technique. Starting with the biharmonic properties of the deformation field, we define an approach based on the Multiridge and ScalFun methods to achieve relevant information about both the positions and shapes of active sources, such as the Mogi source. Our methodology is definitely different from the methods currently used for modeling ground-deformation sources, mainly based on forward or inverse techniques. In fact, (i) it does not require any assumptions about the source type, and (ii) it is not influenced by the distribution of medium elastic parameters or (iii) the presence of high-frequency noise in the dataset. For synthetic cases, we accurately estimate the depth to the source within a 3% error. Finally, we study the real case of the Okmok volcano ground-deformation field and achieve results compatible with those in previous works.

5.
Sci Rep ; 8(1): 8229, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844430

RESUMO

We analyze a wide gravity low in the Campania Active Volcanic Area and interpret it by a large and deep source distribution of partially molten, low-density material from about 8 to 30 km depth. Given the complex spatial-temporal distribution of explosive volcanism in the area, we model the gravity data consistently with several volcanological and petrological constraints. We propose two possible models: one accounts for the coexistence, within the lower/intermediate crust, of large amounts of melts and cumulates besides country rocks. It implies a layered distribution of densities and, thus, a variation with depth of percentages of silicate liquids, cumulates and country rocks. The other reflects a fractal density distribution, based on the scaling exponent estimated from the gravity data. According to this model, the gravity low would be related to a distribution of melt pockets within solid rocks. Both density distributions account for the available volcanological and seismic constraints and can be considered as end-members of possible models compatible with gravity data. Such results agree with the general views about the roots of large areas of ignimbritic volcanism worldwide. Given the prolonged history of magmatism in the Campania area since Pliocene times, we interpret the detected low-density body as a developing batholith.

6.
Minerva Chir ; 68(3): 299-306, 2013 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-23774095

RESUMO

AIM: Self expandable metal stent (SEMS) can be used to relieve malignant colorectal obstruction. The stent serves as a palliative measure for high-risk patients or those with unresectable tumor on subsequent workup. For low-risk patients with resectable disease, SEMS serves as a safe and effective bridge to subsequent laparoscopic surgery. METHODS: From August 2009 to April 2012 we have treated with SEMS 39 patients, 20 of whom with palliative purpose; 19 patients are treated with SEMS for bridge to surgery, out of these patients, 8 were women, 11 men with median age of 61.4 years (range 36-81 years). Technical success, defined as a successful stent placement and deployment in the stricture site, was achieved for 39/40 patients (97.5%). The average duration of the procedure was about 60 minutes (range 15-120). RESULTS: Clinical success was achieved for all the 39 patients, 19 of these could be subjected to bowel preparation and colon resection after 25 days from the positioning. No colostomy was performed. Among patients undergoing the procedure, perforation occurred in 1 case. CONCLUSION: In summary, the colonic stent placement is a complex method that needs qualified medical-nursing team, able to solve any difficult situation, such as the severe, irregular and distal obstruction. SEMS positioning guarantees a high percentage of clinical and technical success; however it is necessary to pay attention to the risk of complications like bowel perforation.


Assuntos
Doenças do Colo/cirurgia , Obstrução Intestinal/cirurgia , Doenças Retais/cirurgia , Stents , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças do Colo/etiologia , Neoplasias Colorretais/complicações , Feminino , Humanos , Obstrução Intestinal/etiologia , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Doenças Retais/etiologia
7.
Anal Bioanal Chem ; 401(6): 2019-23, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21800128

RESUMO

Bones are potentially the best age indicators in a stratigraphic study, because they are closely related to the layer in which they are found. Collagen is the most suitable fraction and is the material normally used in radiocarbon dating. Bone contaminants can strongly alter the carbon isotopic fraction values of the samples, so chemical pretreatment for (14)C dating by accelerator mass spectrometry (AMS) is essential. The most widespread method for collagen extraction is based on the Longin procedure, which consists in HCl demineralization to dissolve the inorganic phase of the samples, followed by dissolution of collagen in a weak acid solution. In this work the possible side effects of this procedure on a modern bone are presented; the extracted collagen was analyzed by ATR-IR spectroscopy. An alternative procedure, based on use of HF instead of HCl, to minimize unwanted degradation of the organic fraction, is also given. A study by ATR-IR spectroscopic analysis of collagen collected after different demineralization times and with different acid volumes, and a study of an archaeological sample, are also presented.


Assuntos
Arqueologia/métodos , Osso e Ossos/química , Radioisótopos de Carbono/análise , Colágeno/isolamento & purificação , Animais , Bovinos , Ácido Clorídrico/química , Coelhos , Espectrofotometria Infravermelho
8.
J Eur Acad Dermatol Venereol ; 25(7): 808-10, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20946585

RESUMO

BACKGROUND: Several patients, especially women, seek advice because of hair loss. They may be diagnosed clinically as having telogen effluvium (TE) or androgenetic alopecia (AGA), but histopathology may reveal that a proportion of them have in fact alopecia areata incognita (AAI). OBJECTIVES: To detect dystrophic anagen hairs in such patients. METHODS: We studied 1932 patients with hair loss and no signs of classical alopecia areata. They were submitted to the modified wash test (which counts the total number of telogen hairs lost and the percentage of vellus hairs) and divided into patients having pure TE (403), patients with AGA+TE (1235) and patients with pure AGA (294). Dystrophic hairs were detected with a low magnification microscope. RESULTS: Dystrophic hairs were observed in 13 patients with TE (3.2%), in 54 with AGA+TE (4.4%) and in none with AGA. In addition, 7 patients with TE and 32 with AGA+TE developed small patches of alopecia areata in 6 to 9 weeks. No patches developed in patients with AGA. CONCLUSIONS: The presence of dystrophic hairs and the development of patches of alopecia areata (and their absence in pure AGA) provide a first evidence of the possibility that within the heterogenous condition named TE some patients have in fact AAI.


Assuntos
Alopecia em Áreas/diagnóstico , Cabelo , Adulto , Alopecia em Áreas/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Br J Radiol ; 82(979): e129-32, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19541939

RESUMO

We report cerebral cystic meningioangiomatosis in a patient with neurofibromatosis type 2. An 18-year-old woman presented with progressive hemiparesis secondary to a meningioma at the foramen magnum. Her MR examination also demonstrated three small cortical and subcortical cystic lesions. She underwent surgery for the meningioma, but died from brainstem infarction. Post-mortem histopathological examination of the cystic lesions showed enlarged subcortical perivascular spaces with overlying meningioangiomatosis. The unusual features and possible pathogenesis are discussed.


Assuntos
Cistos do Sistema Nervoso Central/patologia , Neoplasias Meníngeas/patologia , Meningioma/patologia , Neurofibromatose 2/complicações , Adolescente , Cistos do Sistema Nervoso Central/complicações , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Neoplasias Meníngeas/complicações , Meningioma/complicações , Paresia/etiologia , Paresia/patologia , Tomografia Computadorizada por Raios X
10.
Neurology ; 71(11): 795-8, 2008 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-18685138

RESUMO

BACKGROUND: Mutations of the neuronal nicotinic acetylcholine (nACh) receptor identified in patients with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) lead to increased sensitivity to ACh. As activation of presynaptic nicotinic receptors augments the release of dopamine in the striatum and the prefrontal regions, we tested the hypothesis that that the alpha4-Ser248Phe mutation affects dopaminergic transmission. METHODS: We measured D(1) receptor binding using [(11)C]-SCH23390 and PET in 12 subjects with the alpha4-Ser248Phe mutation (3 men, mean age 41 +/- 16 years) and 19 controls (8 men, mean age 36 +/- 13 years) matched for gender, smoking status, and age. Parametric images were produced using the simplified reference region method. Both MRI-based regions of interest and voxel based analyses were used. RESULTS: Reduced striatal [(11)C]-SCH23390 binding occurred with the mutation (controls 1.1 +/- 0.1; ADNFLE 0.97 +/- 0.2; p < 0.01). Statistical parametric mapping confirmed a region of reduced [(11)C]-SCH23390 binding in the right putamen in alpha4-Ser248Phe subjects compared to controls (309 voxels, local maxima 20 16 -2 mm; Z(score) 3.57, p < 0.05). CONCLUSIONS: Reduced D(1) receptor binding may represent increased extracellular dopamine levels or, more likely, receptor downregulation. Alterations in mesostriatal dopaminergic circuits may contribute to nocturnal paroxysmal motor activity in autosomal dominant nocturnal frontal lobe epilepsy.


Assuntos
Corpo Estriado/metabolismo , Epilepsia do Lobo Frontal/genética , Epilepsia do Lobo Frontal/metabolismo , Receptores de Dopamina D1/metabolismo , Adulto , Feminino , Genes Dominantes/genética , Humanos , Masculino , Pessoa de Meia-Idade , Distonia Paroxística Noturna/genética , Distonia Paroxística Noturna/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Ligação Proteica/fisiologia , Receptores de Dopamina D1/antagonistas & inibidores
11.
Phys Rev Lett ; 92(20): 207204, 2004 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-15169379

RESUMO

The problem of finite-size effects in s=1/2 Ising systems showing slow dynamics of the magnetization is investigated introducing diamagnetic impurities in a Co2+-radical chain. The static magnetic properties have been measured and analyzed considering the peculiarities induced by the ferrimagnetic character of the compound. The dynamic susceptibility shows that an Arrhenius law is observed with the same energy barrier for the pure and the doped compounds while the prefactor decreases, as theoretically predicted. Multiple spin reversal has also been investigated.

12.
Neurology ; 60(5): 756-61, 2003 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-12629229

RESUMO

OBJECTIVE: To determine whether metabolism in the brain serotonergic system, including the kynurenine pathway, is involved in temporal lobe epilepsy (TLE). METHODS: The authors studied 14 patients with intractable TLE by PET using alpha-[11C] methyl-L-tryptophan (alpha-MTrp) and 2-[18F]-fluoro-deoxy-glucose (FDG) and compared results with 21 healthy control subjects who had alpha-MTrp PET studies. Seven patients had unilateral hippocampal atrophy (HA), and seven had normal hippocampal volumes (NV). The regional uptake constant (K*) for alpha-MTrp and regional FDG uptake were calculated in regions with high serotonergic innervation, including the hippocampus, amygdala, lateral temporal lobe, frontal lobe, thalamus, lenticular nucleus, and cingulate cortex. RESULTS: A significant increase of alpha-MTrp uptake was observed in the hippocampus ipsilateral to the seizure focus in seven TLE patients with NV compared to seven patients with HA as well as to healthy controls. In patients with TLE, glucose utilization in the lateral temporal lobe ipsilateral to the seizure focus was correlated negatively with K* for alpha-MTrp in the ipsilateral hippocampus and positively with K* in the ipsilateral lenticular nucleus and cingulate cortex. Glucose utilization in the frontal lobe ipsilateral to the seizure shows a reduction in the glucose utilization which relates to the increase in the alpha-MTrp uptake in the ipsilateral lateral temporal lobe. CONCLUSION: This study demonstrates dysfunction of the serotonergic system, which could include metabolism through the kynurenine pathway in TLE patients with normal hippocampal volumes. alpha-MTrp PET studies might be useful for lateralizing the epileptic focus in TLE patients with normal hippocampal volumes.


Assuntos
Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/metabolismo , Glucose/metabolismo , Triptofano/análogos & derivados , Triptofano/metabolismo , Adolescente , Adulto , Idoso , Tonsila do Cerebelo/metabolismo , Atrofia/diagnóstico , Córtex Cerebral/metabolismo , Feminino , Glucose/farmacocinética , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Cinurenina/metabolismo , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão
13.
Neurology ; 57(9): 1629-36, 2001 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-11706103

RESUMO

BACKGROUND: [(11)C] alpha-methyl-L-tryptophan (alpha-MTrp) has been developed as a tracer for the study of the synthesis of serotonin in the brain with PET. However, it has been shown that in pathologic conditions the tracer may reflect the activation of kynurenine metabolism. Increased levels of serotonin and quinolinic acid have been described in resected epileptogenic cortex, raising the possibility that alpha-MTrp can localize seizure foci in patients with intractable partial epilepsy. The authors assessed the uptake of alpha-MTrp in 18 patients (11 men, mean +/- SD age 27.1 +/- 10.1 years, range 13 to 54) with intractable partial epilepsy to correlate the PET findings with the epileptogenic area defined by electroclinical and neuroimaging data. METHOD: Seven patients with cortical dysplasia (CD) and 11 with partial epilepsy in which conventional MRI and fluorine-18-deoxyglucose ((18)FDG)-PET studies failed to detect any abnormality were studied. All underwent scalp EEG monitoring during the PET scan to exclude ictal events and estimate the interictal epileptic activity. RESULTS: In seven patients (39%; CD four and cryptogenic partial epilepsy three), PET showed focal increased uptake of alpha-MTrp corresponding to the epileptogenic area. alpha-MTrp uptake in the epileptic focus correlated with the frequency of interictal spikes (r = 0.7, p < 0.05). CONCLUSIONS: alpha-MTrp-PET may be of value in the localization of the epileptogenic area not only in patients with visible dysplastic lesions, but also in those with cryptogenic partial epilepsy.


Assuntos
Epilepsias Parciais/diagnóstico por imagem , Epilepsias Parciais/patologia , Neocórtex/patologia , Tomografia Computadorizada de Emissão , Triptofano/análogos & derivados , Adolescente , Adulto , Radioisótopos de Carbono , Eletroencefalografia , Epilepsias Parciais/cirurgia , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Neocórtex/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único
14.
Arch Neurol ; 58(5): 781-6, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11346373

RESUMO

BACKGROUND: Piracetam has been proven to be effective and well tolerated in the treatment of myoclonus in short-term studies. OBJECTIVE: To assess its long-term clinical efficacy, 11 patients with disabling myoclonus due to progressive myoclonus epilepsy were treated with piracetam in an open-label study. METHODS: Neurologic outcome (at the 1st, 6th, 12th, and 18th month of treatment) was assessed by an adjusted sum score of the following 3 indices: motor impairment, functional disability, and global assessment of disability due to myoclonus. Severity of other neurologic symptoms (seizure frequency and severity, dysarthria, and gait ataxia) also was assessed. Treatment with piracetam was initiated at a dose of 3.2 g/d that was gradually increased until stable benefit was noted (maximal dose in the trial was 20 g/d). Concomitant antiepileptic drugs were maintained at their previous dose. RESULTS: Statistically significant improvement in the total rating score was observed after introduction of piracetam at the 1st, 6th, and 12th month of treatment. Severity of other neurologic symptom scores did not improve significantly. Two patients reported drowsiness during the first 2 weeks of treatment. CONCLUSIONS: Piracetam given as add-on therapy seems to be an effective, sustained, and well-tolerated treatment of myoclonus. In patients with progressive myoclonus epilepsy, the efficacy of the drug increased during the first 12 months of treatment and then stabilized.


Assuntos
Epilepsias Mioclônicas/tratamento farmacológico , Nootrópicos/efeitos adversos , Nootrópicos/uso terapêutico , Piracetam/efeitos adversos , Piracetam/uso terapêutico , Adolescente , Adulto , Anticonvulsivantes/uso terapêutico , Avaliação da Deficiência , Progressão da Doença , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Epilepsias Mioclônicas/fisiopatologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Nootrópicos/administração & dosagem , Piracetam/administração & dosagem , Segurança , Resultado do Tratamento
15.
Epileptic Disord ; 1(4): 229-32, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10937158

RESUMO

To our knowledge, petit mal status lasting longer than 2-3 days has been documented only once [1]. We report a 66 year-old man with well-documented, idiopathic generalized epilepsy who developed petit mal status lasting 6 weeks. Valproate levels remained low because of interactions with phenytoin. When phenytoin was discontinued, valproate levels increased, and he progressively improved. Chronic ischemic changes in the white matter may have been an additional factor in the causation and, most likely, in the duration of his status. Exceptionally long status and stupor increase the risk of medical complications. Valproate remains the medication of choice for the treatment of petit mal status. Despite the extraordinary course in this patient, complete recovery took place, confirming the benign nature of even such a prolonged episode.


Assuntos
Anticonvulsivantes/efeitos adversos , Isquemia Encefálica/complicações , Epilepsia Generalizada/tratamento farmacológico , Fenitoína/efeitos adversos , Estado Epiléptico/etiologia , Ácido Valproico/efeitos adversos , Idoso , Anticonvulsivantes/uso terapêutico , Isquemia Encefálica/diagnóstico , Demência Vascular/complicações , Demência Vascular/diagnóstico , Interações Medicamentosas , Hérnia Inguinal/cirurgia , Humanos , Masculino , Fenitoína/uso terapêutico , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/etiologia , Estado Epiléptico/diagnóstico , Estado Epiléptico/tratamento farmacológico , Ácido Valproico/uso terapêutico
17.
Mondo Ortod ; 16(4): 483-6, 1991.
Artigo em Italiano | MEDLINE | ID: mdl-1784286

RESUMO

The Authors evaluate the most common techniques to close the bite in patients with no overjet, then they suggest a method (anterior cross-bite elastics) that can obviate some of the disadvantages experienced using those techniques.


Assuntos
Má Oclusão/terapia , Ortodontia Corretiva/métodos , Humanos , Aparelhos Ortodônticos
18.
Arzneimittelforschung ; 40(10): 1089-92, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1705424

RESUMO

Physico-chemical properties, i.e. elemental analysis, spectra (NMR, MS, IR, UV), X-ray crystal structure, solubilities, partition coefficient, melting point, HPLC, GC, and data about purity and stability of 1,3-dimethyl-7-isobutyl xanthine (isbufylline, TE/06, CAS 90162-60-0), a new drug with antibronchospastic properties, are reported.


Assuntos
1-Metil-3-Isobutilxantina/análogos & derivados , Broncodilatadores/química , 1-Metil-3-Isobutilxantina/síntese química , 1-Metil-3-Isobutilxantina/química , 1-Metil-3-Isobutilxantina/farmacologia , Broncodilatadores/síntese química , Fenômenos Químicos , Físico-Química , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Pós , Solubilidade , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Difração de Raios X
19.
J Chromatogr ; 487(2): 331-40, 1989 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-2723000

RESUMO

In connection with pharmacokinetic studies on the antihypertensive drug 1-[2-ethoxy-2-(3'-pyridyl)ethyl]-4-(2'-methoxyphenyl)piperazine (IP/66) (I), appropriate high-performance liquid chromatographic (HPLC) and gas chromatographic-mass spectrometric isotope dilution (GC-MS-ID) methods for its determination in rat and human plasma, respectively, were developed. In both techniques, deproteinized and basified plasma samples were extracted and purified by adsorption on an Extrelut-1 column, then the drug was eluted with dichloromethane. Quantitative HPLC analysis was performed on a C8 reversed-phase column. The mobile phase was phosphate buffer (0.02 M, pH 2.8)-acetonitrile (65:35), with UV detection at 208 nm. The internal standard was 1-[2-butoxy-2-(3'-pyridyl)ethyl]-4-(2'-methoxyphenyl)piperazine, a homologue of I. The inter-assay coefficient of variation (C.V.) was 9.9% for a drug level of 2 micrograms/ml. Quantitative GC-MS-ID analysis was performed with a DB-17 fused-silica capillary column using the selected-ion monitoring technique. The deuterated form of I, 1-[2-ethoxy-2-(3'-pyridyl)ethyl]-4-2'-trideuteromethoxyphenyl)pipe razine, utilized as internal standard, was synthesized. The inter-assay C.V. was 7.36% for a drug level of 1 ng/ml.


Assuntos
Anti-Hipertensivos/sangue , Piperazinas/sangue , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Espectrometria de Massas , Ratos , Ratos Endogâmicos , Comprimidos
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