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1.
Mol Pharm ; 12(3): 684-94, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25581526

RESUMO

Protein-based biopharmaceuticals are generally produced as aqueous solutions and stored refrigerated to obtain sufficient shelf life. Alternatively, proteins may be freeze-dried in the presence of sugars to allow storage stability at ambient conditions for prolonged periods. However, to act as a stabilizer, these sugars should remain in the glassy state during storage. This requires a sufficiently high glass transition temperature (Tg). Furthermore, the sugars should be able to replace the hydrogen bonds between the protein and water during drying. Frequently used disaccharides are characterized by a relatively low Tg, rendering them sensitive to plasticizing effects of residual water, which strongly reduces the Tg values of the formulation. Larger sugars generally have higher Tgs, but it is assumed that these sugars are limited in their ability to interact with the protein due to steric hindrance. In this paper, the size and molecular flexibility of sugars was related to their ability to stabilize proteins. Four diverse proteins varying in size from 6 kDa to 540 kDa were freeze-dried in the presence of different sugars varying in size and molecular flexibility. Subsequently, the different samples were subjected to an accelerated stability test. Using protein specific assays and intrinsic fluorescence, stability of the proteins was monitored. It was found that the smallest sugar (disaccharide trehalose) best preserved the proteins, but also that the Tg of the formulations was only just high enough to maintain sufficient vitrification. When trehalose-based formulations are exposed to high relative humidities, water uptake by the product reduces the Tgs too much. In that respect, sugars with higher Tgs are desired. Addition of polysaccharide dextran 70 kDa to trehalose greatly increased the Tg of the formulation. Moreover, this combination also improved the stability of the proteins compared to dextran only formulations. The molecularly flexible oligosaccharide inulin 4 kDa provided better stabilization than the similarly sized but molecularly rigid oligosaccharide dextran 6 kDa. In conclusion, the results of this study indicate that size and molecular flexibility of sugars affect their ability to stabilize proteins. As long as they maintain vitrified, smaller and molecularly more flexible sugars are less affected by steric hindrance and thus better capable at stabilizing proteins.


Assuntos
Carboidratos/química , Estabilidade de Medicamentos , Estabilidade Proteica , Proteínas/química , Biofarmácia , Química Farmacêutica , Armazenamento de Medicamentos , Liofilização , Humanos , Estrutura Molecular , Peso Molecular , Espectrometria de Fluorescência , Temperatura de Transição
3.
Neurology ; 63(12): 2396-8, 2004 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-15623710

RESUMO

Whether autoimmune mechanisms play a role in the pathogenesis of inclusion body myositis (IBM) is unknown. Human leukocyte antigen (HLA) analysis in 52 patients, including 17 with autoimmune disorders (AIDs), showed that patients were more likely to have antigens from the autoimmune-prone HLA-B8-DR3 ancestral haplotype than healthy control subjects, irrespective of the presence of AIDs. Patients lacked the apparently protective HLA-DR53 antigen. The results provide further support for an autoimmune basis in IBM.


Assuntos
Doenças Autoimunes/epidemiologia , Genes MHC da Classe II , Genes MHC Classe I , Antígenos HLA/análise , Antígenos HLA-D/análise , Miosite de Corpos de Inclusão/epidemiologia , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Comorbidade , Feminino , Frequência do Gene , Predisposição Genética para Doença , Antígenos HLA/genética , Antígenos HLA/imunologia , Antígenos HLA-D/genética , Antígenos HLA-D/imunologia , Antígenos HLA-DR/análise , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Cadeias HLA-DRB4 , Haplótipos/genética , Humanos , Masculino , Pessoa de Meia-Idade , Miosite de Corpos de Inclusão/genética , Miosite de Corpos de Inclusão/imunologia , Países Baixos/epidemiologia , Prevalência
4.
Artigo em Inglês | MEDLINE | ID: mdl-12535844

RESUMO

Meloxicam was quantified in human plasma after a single 15 mg oral dose of the drug was given to 26 healthy volunteers. An Applied Biosystems Sciex API 2000 triple quadrupole mass spectrometer in multiple reaction monitoring (MRM) mode, using TurboIonSpray (TIS) in the positive ion mode, was used. Protein precipitation with acetonitrile was followed by C(18) reverse phase liquid chromatography and tandem mass spectrometry. The mean recovery for meloxicam was 92% with a lower limit of quantification of 8.96 ng/ml. Piroxicam was used as the internal standard. This assay method makes use of the increased sensitivity and selectivity of tandem mass spectrometry (MS-MS) detection to allow for a more rapid (extraction and chromatography) and selective method for the determination of meloxicam in human plasma than has previously been described.


Assuntos
Anti-Inflamatórios não Esteroides/sangue , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Tiazinas/sangue , Tiazóis/sangue , Humanos , Meloxicam , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Artigo em Inglês | MEDLINE | ID: mdl-12031836

RESUMO

Following a single 10-mg oral dose of cetirizine dihydrochloride to 24 healthy volunteers, the analyte was quantified in human plasma. Protein precipitation using acetonitrile (ACN) was followed by reversed-phase liquid chromatography and tandem mass spectrometry. The MS/MS method was optimised using a PE Sciex API 2000 triple quadrupole mass spectrometer in selected reaction monitoring (SRM) mode, using electrospray with positive ionisation. Oxybutynin was used as the internal standard. The assay method represents a robust, high-throughput, highly specific and sensitive quantitative assay procedure, with 0.5 ng/ml being the lowest plasma concentration that could be reliably quantified. The procedure involves minimal sample preparation, and is well suited to clinical studies of the drug involving large numbers of generated samples. Pre-dose as well as post-dose samples up to and including 48 h were quantified, and the data generated were used to determine the pharmacokinetic profile of the drug.


Assuntos
Cetirizina/sangue , Cromatografia Líquida/métodos , Antagonistas dos Receptores Histamínicos H1/sangue , Espectrometria de Massas/métodos , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Artigo em Inglês | MEDLINE | ID: mdl-11890168

RESUMO

A sensitive method for the determination of clarithromycin in plasma is described, using high-performance liquid chromatographic separation with tandem mass spectrometric detection. Samples were prepared using liquid-liquid extraction and separated on a Supelco Discovery C18 column with a mobile phase consisting of acetonitrile, methanol and acetic acid. Detection was performed by a PE SCIEX API 2000 mass spectrometer in the multiple reaction monitoring (MRM) mode (LC-MS-MS) using TurbolonSpray ionization and monitoring the transition of the protonated molecular ion for clarithromycin at m/z 748.5 (M+1) to the predominant product ion of m/z 158.2. The mean recovery of clarithromycin was 87.3%, with a lower limit of quantification of 2.95 ng/ml when using 0.3-ml plasma. This high-throughput method was used to quantify 230 samples per day, and is sufficiently sensitive to be employed in pharmacokinetic studies.


Assuntos
Antibacterianos/sangue , Cromatografia Líquida/métodos , Claritromicina/sangue , Espectrometria de Massas/métodos , Antibacterianos/farmacocinética , Calibragem , Claritromicina/farmacocinética , Humanos , Sensibilidade e Especificidade
7.
J Neurol Neurosurg Psychiatry ; 71(5): 615-20, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11606672

RESUMO

OBJECTIVE: To describe the clinical, neurophysiological, and MRI findings in 10 patients with primary lateral sclerosis (PLS). RESULTS: The course of the disease was very slowly progressive. Spasticity due to upper motor neuron dysfunction was the most prominent sign, but EMG showed slight lower motor neuron signs, such as a mixed pattern on maximal voluntary contraction and enlarged motor unit potentials. One patient had clinically mild lower motor neuron involvement. Central motor conduction times (CMCT) were more prolonged in PLS than is the case in ALS. Minor sensory signs were found on neurophysiological examination, comparable with those in ALS. In four patients serum creatine kinase activity was raised. On MRI cortical atrophy was seen, most pronounced in the precentral gyrus and expanding into the parietal-occipital region. CONCLUSIONS: PLS is a distinct clinical syndrome, part of the range of motor neuron diseases. Besides pronounced upper motor neuron symptoms, mild lower motor neuron symptoms can also be found, as well as (subclinical) sensory symptoms. PLS can be distinguished from ALS by its slow clinical course, a severely prolonged MEP, and a more extensive focal cortical atrophy.


Assuntos
Encéfalo/patologia , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética , Doença dos Neurônios Motores/diagnóstico , Doença dos Neurônios Motores/fisiopatologia , Adulto , Atrofia/patologia , Creatina Quinase/sangue , Avaliação da Deficiência , Eletromiografia , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios Motores/fisiologia , Condução Nervosa/fisiologia , Lobo Occipital/patologia , Lobo Parietal/patologia , Índice de Gravidade de Doença , Fatores de Tempo
8.
J Agric Food Chem ; 49(8): 3606-13, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11513636

RESUMO

Consumers' increasing interest in the relationship between diet and health is a sign for food producers to pay more attention to potential health-protecting compounds in new product development and food processing. From a production chain perspective the choice of the raw material that is used is important for the health-protecting potential of the end product. Four apple cultivars (Jonagold, Golden Delicious, Cox's Orange, and Elstar), which can be used as fresh apples or in processed apple products, were compared with regard to flavonol, catechins, phloridzin, and chlorogenic acid concentrations and antioxidant activity. Jonagold apples possessed the highest flavonoid concentration and the highest antioxidant activity. To study seasonal differences, apples from three different harvest years were analyzed, but in three cultivars no effect on flavonoid concentration and antioxidant activity was observed. Long-term storage, both at refrigerator temperature and under controlled atmosphere conditions, was found not to influence flavonoid concentration or antioxidant activity.


Assuntos
Antioxidantes/farmacologia , Flavonoides , Malus/metabolismo , Fenóis/farmacologia , Polímeros/farmacologia , Manipulação de Alimentos , Malus/química , Polifenóis , Estações do Ano
9.
J Chromatogr A ; 914(1-2): 37-43, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11358228

RESUMO

A sensitive method for the simultaneous determination of loratadine and its major active metabolite descarboethoxyloratadine (DCL) in plasma was developed, using high-performance liquid chromatographic separation with tandem mass spectrometric detection. The samples were extracted from plasma with toluene followed by back-extraction into formic acid (2%) for DCL after which the toluene containing the loratadine was evaporated, the analyte reconstituted and combined with the DCL back-extract. Chromatography was performed on a Phenomenex Luna C18 (2) 5-microm, 150x2.1-mm column with a mobile phase consisting of acetonitrile-0.1% formic acid using gradient elution (10 to 90% acetonitrile in 2 min) at a flow-rate of 0.3 ml/min. Detection was achieved by a Perkin-Elmer API 2000 mass spectrometer (LC-MS-MS) set at unit resolution in the multiple reaction monitoring mode. TurbolonSpray ionisation was used for ion production. The mean recovery for loratadine and descarboethoxyloratadine was 61 and 100%, respectively, with a lower limit of quantification at 0.10 ng/ml for both the analyte and its metabolite. This is the first assay method described for the simultaneous determination of loratadine and descarboethoxyloratadine in plasma using one chromatographic run. The method is sensitive and reproducible enough to be used in pharmacokinetic studies.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Antagonistas dos Receptores Histamínicos H1/sangue , Loratadina/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Loratadina/análogos & derivados , Reprodutibilidade dos Testes
10.
J Chromatogr A ; 914(1-2): 45-51, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11358229

RESUMO

A sensitive method for the simultaneous determination of fluoxetine and its major active metabolite norfluoxetine in plasma was developed, using high-performance liquid chromatographic separation with tandem mass spectrometric detection. The samples were extracted from alkalised plasma with hexane-isoamyl alcohol (98:2, v/v) followed by back-extraction into formic acid (2%). Chromatography was performed on a Phenomenex Luna C18 (2) 5 microm, 150x2 mm column with a mobile phase consisting of acetonitrile-0.02% formic acid (340:660, v/v) at a flow-rate of 0.35 ml/min. Detection was achieved by a Perkin-Elmer Sciex API 2000 mass spectrometer (LC-MS-MS) set at unit resolution in the multiple reaction monitoring mode. TurbolonSpray ionisation was used for ion production. The mean recoveries for fluoxetine and norfluoxetine were 98 and 97%, respectively, with a lower limit of quantification set at 0.15 ng/ml for the analyte and its metabolite. This assay method makes use of the increased sensitivity and selectivity of mass spectrometric (MS-MS) detection to allow for a more rapid (extraction and chromatography) and sensitive method for the simultaneous determination of fluoxetine and norfluoxetine in human plasma than has previously been described.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fluoxetina/sangue , Espectrometria de Massas/métodos , Inibidores Seletivos de Recaptação de Serotonina/sangue , Fluoxetina/análogos & derivados , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Neurology ; 56(2): 228-33, 2001 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-11160960

RESUMO

BACKGROUND: In polyneuropathy associated with immunoglobulin M (IgM) monoclonal gammopathy, antibodies to myelin-associated glycoprotein (MAG), sulfoglucuronyl paragloboside (SGPG), and sulfatide have been associated with specific clinical and electrophysiologic features. However, it is not known whether the results of antibody tests provide additional information for the individual patient (and the neurologist) in terms of future neurologic deficit or outcome. OBJECTIVE: To study the independent contribution of potential prognostic factors to the prediction of outcome of neuropathy associated with IgM monoclonal gammopathy. METHODS: In accordance with the chronology in which prognostic factors are available in clinical practice, the association between prognostic factors and outcome was evaluated by univariate and multivariate logistic regression analysis in 65 patients with polyneuropathy and IgM monoclonal gammopathy. RESULTS: In univariate analysis, the initial symptoms, the IgM light chain type, electrophysiologic and pathologic studies, the presence of sural nerve IgM deposition, and anti-MAG or anti-SGPG antibodies were significantly associated with outcome. However, multivariate analysis showed that only initial symptoms and electrophysiologic studies are independent prognostic factors: initial sensory symptoms of the feet are prognostic for a slowly progressive disease course and less disability at 4 years, and evidence for demyelination on electrophysiologic examination is prognostic for development of weakness and symptoms of the upper extremities at 4 years. Addition of anti-MAG or anti-SGPG antibody tests did not yield any additional prediction of outcome. CONCLUSION: These results indicate that in clinical practice, antibody tests in polyneuropathy associated with IgM monoclonal gammopathy do not have a prognostic value in terms of future neurologic deficit or outcome.


Assuntos
Globosídeos/imunologia , Imunoglobulina M/imunologia , Glicoproteína Associada a Mielina/imunologia , Doenças do Sistema Nervoso/imunologia , Paraproteinemias/imunologia , Sulfoglicoesfingolipídeos/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
12.
J Neurol Sci ; 181(1-2): 104-10, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11099719

RESUMO

Temporal changes in serum S-100 protein levels were compared between patients with ischemic stroke, transient ischemic attack (TIA) and traumatic brain injury (TBI). In addition, S-100 levels were correlated with clinical severity and outcome. Measurements were done with a LIA-mat((R)) Sangtec((R)) 100 using an automated immunoluminometric assay. Serum S-100 was measured in 21 stroke patients, 18 TIA patients and ten TBI patients on days 1 (0-24 h), 2, 3, 4, 5 or 6 and 8 or 9. In a control group of 28 healthy volunteers one measurement was done. For the stroke and TIA patients, National Institutes of Health Stroke Scale (NIHSS) scores were obtained on admission and on day 10. For the TBI patients, Glasgow Coma Scale (GCS) scores were obtained on admission and Glasgow Outcome Scale (GOS) scores were obtained after 6 months. Changes in serum S-100 levels over the first 3 days were significantly different between stroke and TBI patients (P=0.014) and between stroke and TIA patients (P=0.006). Peak concentrations of S-100 were most often observed on day 3 or 4 after stroke and on day 1 or 2 after TBI. In the stroke patients individual S-100 peak levels correlated well with the NIHSS score on admission (r=0.58 P=0.014) and the change in NIHSS score between day 10 and day 1 (r=0.65, P=0. 005). In the TBI patients a good correlation between individual peak levels of S-100 and the GCS score on admission (r=-0.81, P=0.010) and the GOS score 6 months after the trauma was found (r=-0.87, P=0. 004). We conclude that there is a significant difference in temporal changes of S-100 levels between ischemic stroke and TBI patients. This suggests different pathophysiological mechanisms. The results of this study further confirm that peak levels of serum S-100 correlate with neurological deficit resulting from either stroke or TBI.


Assuntos
Lesões Encefálicas/sangue , Proteínas S100/sangue , Acidente Vascular Cerebral/sangue , Adulto , Idoso , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/fisiopatologia , Isquemia Encefálica/sangue , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/fisiopatologia , Progressão da Doença , Feminino , Humanos , Ataque Isquêmico Transitório/sangue , Ataque Isquêmico Transitório/diagnóstico por imagem , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Tomografia Computadorizada por Raios X/estatística & dados numéricos
13.
Neurology ; 55(9): 1385-7, 2000 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-11087787

RESUMO

Epidemiologic data on inclusion body myositis (IBM) are scarce, and possibly biased, because they are derived from larger neuromuscular centers. The present nationwide collaborative cross-sectional study, which culminated on July 1, 1999, resulted in identification of 76 patients with IBM and the establishment of a prevalence of 4.9 patients with IBM per million inhabitants in the Netherlands. Several discrepancies suggest that this may be an underestimation. The most frequently identified pitfall in diagnosing IBM was an erroneous diagnosis of polymyositis or motor neuron disease.


Assuntos
Miosite de Corpos de Inclusão/epidemiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Prevalência
14.
Amyloid ; 7(3): 218-21, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11019863

RESUMO

A Dutch family with familial amyloidotic polyneuropathy associated with the transthyretin mutation Val71Ala is described. This is the third reported family with this mutation, causing at the protein level an unstable TTR monomer and at the clinical level progressive wasting, polyneuropathy, autonomic dysfunction and vitreous opacities.


Assuntos
Substituição de Aminoácidos , Neuropatias Amiloides/genética , Mutação Puntual , Pré-Albumina/genética , Adulto , Idoso , Neuropatias Amiloides/patologia , Eletroforese das Proteínas Sanguíneas , Evolução Fatal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos
15.
J Chromatogr B Biomed Sci Appl ; 742(1): 91-8, 2000 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-10892587

RESUMO

A sensitive method for the simultaneous determination of doxepin and its active metabolite desmethyldoxepin in plasma was established, using high-performance liquid chromatographic separation with tandem mass spectrometric detection. The samples were extracted with hexane-isoamyl alcohol, separated on a Phenomenex Luna C18 5 microm, 150x2.1 mm column with a mobile phase consisting of methanol-water-formic acid (600:400:0.5, v/v) at a flow-rate of 0.25 ml/min. Detection was achieved by a Perkin-Elmer API 2000 mass spectrometer at unit resolution in multiple reaction monitoring mode monitoring the transition of the protonated molecular ions m/z 280.2, 266.2 and 250.1 to the product ions m/z 107.1, 107.1 and 191.0 for analyte, metabolite and internal standard (benzoctamine-HCl), respectively. TurbolonSpray ionisation was used for ion production. The mean recovery for doxepin and desmethyldoxepin was 90% and 75%, respectively, with a lower limit of quantification at 0.320 ng/ml and 0.178 ng/ml for the analyte and its metabolite, respectively, using 0.5 ml plasma for extraction. This is the first assay method described for the simultaneous determination of doxepin and desmethyldoxepin in plasma using LC-MS-MS. The method is sensitive enough to be used in drug bioavailability studies with doxepin.


Assuntos
Antidepressivos Tricíclicos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Doxepina/análogos & derivados , Doxepina/sangue , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray
16.
J Chromatogr B Biomed Sci Appl ; 740(2): 247-51, 2000 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-10821411

RESUMO

Following oral administration of the prodrug nabumetone, the major metabolite 6-methoxy-2-naphthylacetic acid (6-MNA) was determined in human plasma. Minimal sample preparation was followed by reversed-phase liquid chromatography and UV detection, affording high sample throughput. The lower limit of quantification (LLOQ) was 70 ng/ml, at a signal-to-noise ratio of 8:1. The assay method displayed good correlation (r=0.997), and can be readily employed in pharmacokinetic and bioequivalence studies.


Assuntos
Anti-Inflamatórios não Esteroides/sangue , Butanonas/sangue , Ácidos Naftalenoacéticos/sangue , Adulto , Anti-Inflamatórios não Esteroides/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Butanonas/farmacocinética , Calibragem , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Feminino , Meia-Vida , Humanos , Indicadores e Reagentes , Masculino , Nabumetona , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta
17.
J Pharm Biomed Anal ; 22(3): 461-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10766363

RESUMO

A sensitive method for the determination of linsidomine in plasma was developed, using high-performance liquid chromatographic (HPLC) separation with tandem mass spectrometric detection. Linsidomine was derivatised with propyl chloroformate and extracted with tert-butyl methyl ether/1,2-dichloroethane (55:45, v/v), back-extracted into HCl (0.01 M) followed by alkalinisation and back-extraction into ether; the final ether extract evaporated, reconstituted in mobile phase and then separated on a Phenomenex Luna C18 (2) 5 micron 2.1 x 150 mm column with a mobile phase consisting of methanol water formic acid (98/100%) (400:600:0.05, v/v/v) at a flow-rate of 0.4 ml min(-1). Detection was achieved by a Finnigan MAT mass spectrometer (LCQ) at unit resolution in the selected reaction monitoring (SRM) mode monitoring the transition of the protonated molecular ion m/z 257.0 to the product ion m/z 86.0. The mean recovery for linsidomine was 51% with a lower limit of quantification of 0.70 ng/ml using 1 ml plasma for extraction. This LC-MS/MS method for the determination of linsidomine in human plasma allows for better specificity and a higher sample throughput than the traditional LC-UV methods. It also demonstrates the profound effect that the composition of acidic modifiers and matrix constituents can have on the electrospray ionisation (ESI) of the analyte.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Molsidomina/análogos & derivados , Vasodilatadores/sangue , Humanos , Troca Iônica , Molsidomina/sangue , Controle de Qualidade , Reprodutibilidade dos Testes
19.
Neurology ; 53(2): 409-10, 1999 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-10430437

RESUMO

Three to six years after onset of Guillain-Barré syndrome, 63% of 122 patients showed one or more changes in their lifestyle, work, or leisure activities, or in the life of their partners. The changes were influenced by an impaired final functional outcome, along with loss of power and poor condition, although physically recovered patients showed these changes as well.


Assuntos
Polirradiculoneuropatia/fisiopatologia , Atividades Cotidianas , Humanos , Prognóstico , Fatores de Tempo
20.
J Chromatogr B Biomed Sci Appl ; 729(1-2): 183-9, 1999 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-10410941

RESUMO

After repeated topical application of a piroxicam gel preparation to the knee, piroxicam was quantified in plasma, subcutaneous tissue, synovial capsule and synovial fluid, using specimens obtained during knee surgery. Electrochemical detection was used and the limit of quantification (LOQ) was 0.72 ng/ml in plasma at a signal-to-noise ratio of 10:1. The chromatographic method was optimised to determine piroxicam in all four matrices, and the analyte was quantified using a calibration line constructed from plasma calibration standards. Levels in subcutaneous tissue, synovial capsule and synovial fluid were compared to plasma steady-state levels and expressed as a ratio, in order to ascertain bioavailability.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Cromatografia Líquida de Alta Pressão/métodos , Piroxicam/análise , Anti-Inflamatórios não Esteroides/sangue , Eletroquímica , Humanos , Piroxicam/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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