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1.
Rev Neurol (Paris) ; 178(10): 1098-1104, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36180289

RESUMEN

BACKGROUND: In clinical practice, the diagnosis of secondary progressive multiple sclerosis (SPMS) is often delayed, retrospective and non-reproducible, as there are no consensus criteria that define the advent of SPMS. Early identification of SPMS is essential to improve patient care. METHODS: Eight regional board meetings in France involving 56 multiple sclerosis (MS) experts (neurologists) were convened to discuss diagnostic criteria for SPMS. Subsequently, a national board meeting of 13 neurologists (with an expert representing each geographical region) was held to review points of convergence or divergence between regions and to develop a national consensus document. RESULTS: Based on the discussions from the regional boards, the MS experts at the national board retained the worsening of the EDSS score, with compatible clinical features, as the only consensus criterion for the diagnosis of SPMS in clinical practice. The patient should have experienced during at least the previous 6 months and in the absence of any relapse, a worsening in the EDSS score of +1.0 point (if the previous EDSS was≤5.0) or of +0.5 point (if the previous EDSS was≥5.5), with a pyramidal or cerebellar functional system score≥2 and without setting a minimum EDSS score; or, in case of a stable EDSS score≥4.0, a worsening of a functional score. This worsening should be confirmed within 3 to 6 months. According to the MS experts, the patient's age, duration of illness and a minimal threshold EDSS score are only risk factors for transition to SPMS. Patient reports during consultation and cognitive impairment are important warning signs, which should trigger an objective assessment with specific tests or closer monitoring. Clinical relapse and/or MRI activities are non-discriminatory for making the diagnosis of SPMS. CONCLUSIONS: The experts defined precise diagnostic criteria adapted to clinical practice for earlier identification of SPMS, paving the way for better management of this stage of the disease.


Asunto(s)
Esclerosis Múltiple Crónica Progresiva , Esclerosis Múltiple , Humanos , Esclerosis Múltiple Crónica Progresiva/diagnóstico , Esclerosis Múltiple/diagnóstico , Estudios Retrospectivos , Progresión de la Enfermedad , Recurrencia
2.
BMC Med Res Methodol ; 22(1): 155, 2022 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-35637426

RESUMEN

BACKGROUND: Natalizumab and fingolimod are used as high-efficacy treatments in relapsing-remitting multiple sclerosis. Several observational studies comparing these two drugs have shown variable results, using different methods to control treatment indication bias and manage censoring. The objective of this empirical study was to elucidate the impact of methods of causal inference on the results of comparative effectiveness studies. METHODS: Data from three observational multiple sclerosis registries (MSBase, the Danish MS Registry and French OFSEP registry) were combined. Four clinical outcomes were studied. Propensity scores were used to match or weigh the compared groups, allowing for estimating average treatment effect for treated or average treatment effect for the entire population. Analyses were conducted both in intention-to-treat and per-protocol frameworks. The impact of the positivity assumption was also assessed. RESULTS: Overall, 5,148 relapsing-remitting multiple sclerosis patients were included. In this well-powered sample, the 95% confidence intervals of the estimates overlapped widely. Propensity scores weighting and propensity scores matching procedures led to consistent results. Some differences were observed between average treatment effect for the entire population and average treatment effect for treated estimates. Intention-to-treat analyses were more conservative than per-protocol analyses. The most pronounced irregularities in outcomes and propensity scores were introduced by violation of the positivity assumption. CONCLUSIONS: This applied study elucidates the influence of methodological decisions on the results of comparative effectiveness studies of treatments for multiple sclerosis. According to our results, there are no material differences between conclusions obtained with propensity scores matching or propensity scores weighting given that a study is sufficiently powered, models are correctly specified and positivity assumption is fulfilled.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Clorhidrato de Fingolimod/uso terapéutico , Humanos , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Natalizumab/uso terapéutico , Resultado del Tratamiento
3.
J Chromatogr A ; 1621: 461078, 2020 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-32312546

RESUMEN

A new derivatization reagent, N-(naphthalen-1-yl)-2-oxopropanehydrazonoyl chloride (UOSA54), was prepared and coupled with four drugs, bearing primary amino, secondary amino or mercapto functional groups. Glucosamine sulfate (GLU), cysteine (CYS), captopril (CAP), and vildagliptin (VIL), were used as representative reactive analytes. The prepared reagent was successfully coupled with the targeted analytes in the presence of triethylamine (TEA) as hydrochloride acceptor and acetonitrile as solvent. The resulting reaction products were separated by high-performance liquid chromatography and monitored simultaneously by diode array and triple quad mass spectrometry detectors. Enhanced DAD and electrospray ionization-MS (ESI-MS) responses were observed for the derivatized products. Complete derivatization of VIL was achieved after heating at 65 ± 3 °C for 4 min, while other analytes were derivatized instantaneously at room temperature. Both, the ESI-ionization suppression, due to the excess reagent, and matrix effect, due to co-eluted biogenic plasma constituents, were negligible. The derivatized GLU, CYS, CAP, and VIL showed a maximum absorption wavelength at 376, 417, 340, and 376 nm, with MS-limit of quantification value of 250.0, 2.0, 2.5, and 3.0 pg/µL, respectively. The relative ESI-MS response of UOSA54 derivatization products was within the range of 0.6-4.1 compared with dansylated products. The method was optimized and validated for optimal reaction product stability, sensitivity, linearity, range, precision, and accuracy. The percentage recovery was exceeding 97.2%, with an RSD value of less than 4.0%. The limit of quantification of targeted analytes was ranged from 80.0 to 0.7 pg/µL.


Asunto(s)
Aminas/análisis , Cromatografía Liquida/métodos , Iminas/análisis , Espectrometría de Masas/métodos , Compuestos de Sulfhidrilo/análisis , Cromatografía Líquida de Alta Presión , Compuestos de Dansilo/química , Fluorenos/síntesis química , Fluorenos/química , Reproducibilidad de los Resultados , Compuestos de Sulfhidrilo/síntesis química , Compuestos de Sulfhidrilo/química
4.
Prog Urol ; 22(16): 1026-32, 2012 Dec.
Artículo en Francés | MEDLINE | ID: mdl-23178100

RESUMEN

INTRODUCTION: Urinary symptoms occur in 50 to 80% of patients with Multiple Sclerosis (MS). This study was conducted to determine prevalence of renal failure during MS follow-up and to investigate the correlation of these complications with disease characteristics and urodynamic findings. METHODS: One hundred and twenty-one consecutive patients have been followed for (MS) (61 men and 60 women) between 1995 and 2009 in our institution. The demographic findings of patients were documented. The history was obtained and a detailed neurological and urological physical examination was performed for all patients. Urological symptoms (urgency, frequency, urge incontinence, dysuria), urinary scores (UPS and International Consultation on Incontinence Questionnaire [ICIQ]) and renal failure were recorded. All patients underwent ultrasound imaging of the bladder during their follow-up and on the last evaluation. Expanded Disability Status Scale (EDSS) was evaluated during neurologic follow-up. For each patient mean onset age of disease, mean onset age of micturation disorders, mean illness duration and mean urological follow-up duration were recorded. Urodynamic investigation was performed for all patients. Urodynamic assessment was carried out according to the International Continence Society (ICS) standards (detrusor overactivity, detrusor/sphincteric dyssynergia and low bladder compliance). RESULTS: Mean illness duration was 13.8 years (1-50). According to the history and clinical findings, 21 patients had primary-progressive (PPMS), 59 relapsing-remitting (RRMS) and 41 secondary-progressive multiple sclerosis (SPMS). Four patients have shown renal failure during their follow-up (3.3% - three men and one woman). Renal failure was associated with disease characteristic (SPMS - EDSS score >6.5), mean illness duration (30 years [12-48]) and low bladder compliance (17 [7-23]) (P=0.03; P=0.02; P=0.049). CONCLUSION: Relationship between renal failure, disease characteristics and urodynamic findings was suggested in our study. More accurate follow-up might be used for SPMS (EDSS >6.5), longer mean illness duration (>30 years), and low bladder compliance (<30).


Asunto(s)
Esclerosis Múltiple/complicaciones , Insuficiencia Renal/complicaciones , Edad de Inicio , Anciano , Estudios de Cohortes , Evaluación de la Discapacidad , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Francia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/epidemiología , Esclerosis Múltiple Crónica Progresiva/complicaciones , Prevalencia , Pronóstico , Estudios Prospectivos , Calidad de Vida , Insuficiencia Renal/diagnóstico , Insuficiencia Renal/epidemiología , Insuficiencia Renal/etiología , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Incontinencia Urinaria de Urgencia/etiología , Urodinámica
6.
J Neurol Neurosurg Psychiatry ; 76(12): 1624-9, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16291883

RESUMEN

BACKGROUND: Data from epidemiological studies and animal models imply that disturbances in cholesterol metabolism are linked to Alzheimer's disease susceptibility. Lipid lowering agents (LLAs) may have implications for the prevention of Alzheimer's disease. OBJECTIVE: To investigate whether LLAs are associated with a slower cognitive decline in Alzheimer's disease. METHODS: An observational study in 342 Alzheimer patients followed in a memory clinic for 34.8 months (mean age 73.5 years, mini-mental state examination score (MMSE) 21.3 at entry); 129 were dyslipaemic treated with LLAs (47% with statins), 105 were untreated dyslipaemic, and 108 were normolipaemic. The rate of cognitive decline was calculated as the difference between the first and last MMSE score, divided by the time between the measurements, expressed by year. Patients were divided into slow and fast decliners according to their annual rate of decline (lower or higher than the median annual rate of decline in the total population). RESULTS: Patients treated with LLAs had a slower decline on the MMSE (1.5 point/year, p = 0.0102) than patients with untreated dyslipaemia (2.4 points/year), or normolipaemic patients (2.6 points/year). Patients with a slower decline were more likely to be treated with LLAs. Logistic regression analysis, with low annual cognitive decline as the dependent variable, showed that the independent variable LLA (treated with or not) was positively associated with the probability of lower cognitive decline (odds ratio = 0.45, p = 0.002). CONCLUSIONS: LLAs may slow cognitive decline in Alzheimer's disease and have a neuroprotective effect. This should be confirmed by placebo controlled randomised trials in patients with Alzheimer's disease and no dyslipaemia.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/etiología , Hipolipemiantes/farmacología , Hipolipemiantes/uso terapéutico , Anciano , Enfermedad de Alzheimer/fisiopatología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Trastornos de la Memoria/tratamiento farmacológico , Trastornos de la Memoria/etiología , Escala del Estado Mental , Resultado del Tratamiento
7.
Rev Neurol (Paris) ; 160(11): 1048-58, 2004 Nov.
Artículo en Francés | MEDLINE | ID: mdl-15602347

RESUMEN

INTRODUCTION: Serological confirmation of an infectious acute myelitis injury is difficult to confirm as it is sometimes due to a post-infectious etiology. OBJECTIVES: The aim of this study was to define the clinical, biological and prognostic patterns of infectious myelitis. PATIENTS AND METHODS: This retrospective study included 153 subjects hospitalized in the department of neurology between 1993 and 2002 for treatment of a noncompressive acute myelopathy. Biological confirmation of recent infection was obtained in 12 patients (8 p. 100). RESULTS: An infectious syndrome, beginning prior to the neurological symptoms, was found in 67 percent of patients. The clinical symptoms were severe with loss of sensoromotor and sphincter functions and ascending spinal cord dysfunction (acute transverse myelopathy). Spinal cord MRI showed extended centromedullar high intensity signals with rapid and complete regression. CSF analysis cell count was above 30/mm3 with hyperproteinorachia, in 75 percent and 58 percent of patients respectively. CSF electrophoresis did not detect oligoclonal bands. Clinical outcome was good in all patients except one, however sphincter disorders recovered slowly. DISCUSSION: Our study illustrates a stereotypical clinical, biological and prognostic pattern for infectious acute myelitis. These findings contribute significantly to therapeutic decision making and establishing prognosis at the initial phase of acute myelopathy.


Asunto(s)
Mielitis/diagnóstico , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mielitis/sangre , Mielitis/tratamiento farmacológico , Pronóstico , Estudios Retrospectivos
8.
J Chromatogr Sci ; 38(4): 151-6, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10766481

RESUMEN

An accurate, reproducible, and sensitive method for the determination of buspirone HCl and its potential impurities is developed and validated. The validated liquid chromaography method is conducted to meet the Food and Drug Administration/ International Conference on Harmonization requirements for the analysis of buspirone HCI in the presence of its impurities. Five buspirone HCI potential impurities, including 1-(2-pyrimidinyl)-piperazine (I), propargyl chloride (II), 3,3'-tetramethylene glutarimide (III), propargyl glutarimide (IV), and the Mannich base-condensate of I-IV fumarate (V), are separated using a microBondapack C18 column by gradient elution with a flow rate 2.0 mL/min. The initial mobile phase composition is 90:10 (v/v) 10mM KH2PO4 (pH 6.1)-acetonitrile. After a 1-min initial hold, a linear gradient is performed in 26 min to 35:65 (v/v) 10mM KH2PO4 (pH 6.1)-acetonitrile. The samples are detected at 210 and 240 nm using a photo-diode array detector. The linear range of detection for buspirone HCI was between 1.25 ng/microL and 500 ng/microL, with a limit of quantification of 1.25 ng/microL. The linearity, range, peak purity, selectivity, system performance parameters, precision, accuracy, and robustness for all of the impurities were also shown to have acceptable values.


Asunto(s)
Buspirona/análisis , Contaminación de Medicamentos , Cromatografía de Gases y Espectrometría de Masas/métodos , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
J Chromatogr Sci ; 37(12): 462-8, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10615593

RESUMEN

The United States Pharmacopoeia high-performance liquid chromatographic (HPLC) assay method of buspirone is not able to discriminate buspirone from its degradation products. The purpose of this work is to develop a sensitive, selective, and validated stability-indicating HPLC assay for the analysis of a buspirone hydrochloride in a bulk drug. Buspirone HCI and its potential impurities and degradation products are analyzed on an Ultrasphere C18 column heated to 40 degrees C using a gradient program that contains monobasic potassium phosphate buffer solution (pH 6.9) and acetonitrile-methanol mixture (13:17) of 35% for 5 minutes, then increased to 54% in 5.5 minutes. The samples are monitored using a photo-diode array detector and integrated at 244 and 210 nm. The stress testing of buspirone HCI shows that buspirone acid hydrochloride is the major degradation product. The developed method shows a separation of buspirone degradation product and its potential impurities in one run. The stability of buspirone HCI is studied under accelerated conditions in order to provide a rapid indication of differences that might result from a change in the manufacturing process or source of the sample. The forced degradation conditions include the effect of heat, moisture, light, acid-base hydrolysis, sonication, and oxidation. The compatibility of buspirone HCI with some pharmaceutical excipients is studied under stress conditions. The linear range of buspirone HCI is between 5 and 200 ng/microL with a limit of quantitation of 2.5 ng/microL. The intraassay percentage deviation is not more than 0.38%, and the day-to-day variation was not more than 0.80%. The selectivity, repeatability, linearity, range, accuracy, sample solution stability, ruggedness, and robustness show acceptable values.


Asunto(s)
Buspirona/análisis , Buspirona/efectos de la radiación , Calibración , Cromatografía Líquida de Alta Presión , Contaminación de Medicamentos , Estabilidad de Medicamentos , Excipientes , Calor , Hidrólisis , Oxidación-Reducción , Soluciones Farmacéuticas , Reproducibilidad de los Resultados , Luz Solar , Ultrasonido
10.
Biomed Chromatogr ; 12(2): 57-60, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9568270

RESUMEN

3-Bromomethyl-propyphenazone (BMP) was used as a derivatization reagent for the detection and quantification of captopril (CAP) and hydrochlorothiazide (HCT) by high performance liquid chromatography using Zorbax C8 column, and 0.05M sodium acetate, acetonitrile, methanol (14:17:4; pH 6.5) as mobile phase system with UV-detection at 254 nm. The cited reagent reacts with the mercapto and amino groups of CAP and HCT in acetone using anhydrous potassium carbonate as hydrobromide acceptor. The reaction was completed within 30 min for CAP and 60 min for HCT with heating at 105 +/- 5 degrees C in mini-reaction vial. The linear concentration ranges for both CAP and HCT were 8 to 160 and 6 to 140 ng per injection, respectively. The derivatized captopril was synthesized and confirmed with spectral analysis. This method was applied for determination of spiked captopril in human urine after extraction with Extrelut-20 column using ethyl acetate:isopropanol (85:15 v/v) as eluant.


Asunto(s)
Antihipertensivos/orina , Antipirina/análogos & derivados , Captopril/orina , Cromatografía Líquida de Alta Presión/métodos , Hidroclorotiazida/orina , Indicadores y Reactivos/química , Inhibidores de los Simportadores del Cloruro de Sodio/orina , Antihipertensivos/administración & dosificación , Antihipertensivos/química , Antipirina/química , Captopril/administración & dosificación , Captopril/química , Diuréticos , Combinación de Medicamentos , Humanos , Hidroclorotiazida/administración & dosificación , Estructura Molecular , Inhibidores de los Simportadores del Cloruro de Sodio/administración & dosificación , Análisis Espectral
11.
Biomed Chromatogr ; 11(6): 356-61, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9413615

RESUMEN

Famprofazone (1) metabolites were studied in human urine after medication by 50 mg oral dose. The human urine was collected over 48 h from six volunteers at time intervals of 6, 12, 24 and 48 h. The amount of famprofazone metabolites were recovered from the urine samples by application of Extrelut extraction method. The resultant extracts were derivatized using N-methyl-N-trimethylsilytrifluoroacetamide (MSTFA) for trimethylsilylation followed by N-methyl-bis-trifluoroacetamide (MBTFA) for trifluoroacetylation. Methamphetamine (2) and 3-hydroxymethyl-propyphenazone (3), excreted in human urine, were identified as famprofazone metabolites by gas chromatography-mass spectrometry (GC-MS). The quantitative results revealed that the average amounts of 2 and 3, excreted in human urine were equal to 2.6 and 4 mg, respectively, through 48 h. However, 3 was analysed after enzymatic hydrolysis of the urine samples using beta-glucuronidase/arylsulphatase. The excreted methamphetamine enantiomers could be separated by application of indirect GC-technique using S-(-)-N-trifluoroacetylprolyl chloride (TPC) as a chiral derivatizing agent. The average amount of (-)-methamphetamine isomer excreted in the urine was found to be three fold those of the (+)-isomer.


Asunto(s)
Antiinflamatorios no Esteroideos/orina , Metanfetamina/análogos & derivados , Pirazoles/orina , Pirazolonas , Administración Oral , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/farmacocinética , Biotransformación , Cromatografía de Gases y Espectrometría de Masas , Humanos , Concentración de Iones de Hidrógeno , Metanfetamina/administración & dosificación , Metanfetamina/farmacocinética , Metanfetamina/orina , Pirazoles/administración & dosificación , Pirazoles/farmacocinética , Valores de Referencia , Estereoisomerismo
12.
Biomed Chromatogr ; 11(1): 42-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9051216

RESUMEN

A high-performance liquid chromatographic method involving on-line precolumn oxidative cleavage and fluorimetric detection was developed for the determination of methotrexate in plasma. Plasma samples were subjected to protein precipitation followed by solvent purification and then injection into the chromatographic system. Cerium (IV) trihydroxyhydroperoxide (CTH) was introduced as a packed oxidant before analytical column for the conversion of methotrexate into highly fluorescent 2,4-diaminopteridine derivatives. The oxidative cleavage of methotrexate occurs during the flow of 0.04 M phosphate buffer (pH 3.5) containing the drug through CTH column with a flow-rate of 0.2 mL/min at 40 degrees C. The separation was performed on a reversed-phase column (ODS/TM) using a mobile phase consisting of phosphate buffer (0.05 M, pH 6.6) and acetonitrile (90:10 v/v). The fluorescent products were monitored fluorimetrically at emission and excitation wavelengths of 463 and 367 nm, respectively. Validation of accuracy and precision were satisfactory for both within- and between-run assays. All coefficients of variance were less than 4% and mean relative errors were within 1.11% to 7.83%. The average recovery was found to be 93.74% to 98.11%. The proposed method is highly sensitive, specific and applicable to biological fluids.


Asunto(s)
Antimetabolitos Antineoplásicos/sangre , Cromatografía Líquida de Alta Presión/métodos , Metotrexato/sangre , Oxidantes , Peróxidos , Acetonitrilos , Proteínas Sanguíneas , Tampones (Química) , Precipitación Química , Estabilidad de Medicamentos , Humanos , Fosfatos , Sensibilidad y Especificidad
13.
Arch Mal Coeur Vaiss ; 89(10): 1317-21, 1996 Oct.
Artículo en Francés | MEDLINE | ID: mdl-8952832

RESUMEN

The authors report the case of a 34-year old woman with no previous cardiovascular disease who was admitted to hospital for acute ischaemia of the right arm due to embolism, preceded by two episodes of pain and tingling of the left arm related to subacute ischaemia. After right embolectomy, with no possibility of controlateral disobliteration an effective anticoagulation, no cardiac source of embolism could be found; However, transoesophageal echography showed a large mobile thrombus in the aortic arch implanted just before the origin of the left subclavian artery. The only explanation for embolism to the right arm was a retro-oesophageal subclavian artery which was confirmed by scanner. Doppler and arteriography. These investigations, however, did not allow visualisation of the aortic thrombus. In view of the risk of recurrent embolism, a thrombectomy was performed without cardiopulmonary bypass, associated with correction of the vascular abnormality with no complications. This case shows that oesophageal echography is a useful investigation in the work up of acute arterial obstruction in young patients with no cardiac disease.


Asunto(s)
Enfermedades de la Aorta/complicaciones , Arteriopatías Oclusivas/etiología , Ecocardiografía Transesofágica , Isquemia/diagnóstico por imagen , Arteria Subclavia , Tromboembolia/complicaciones , Enfermedad Aguda , Adulto , Angiografía de Substracción Digital , Aorta Torácica , Enfermedades de la Aorta/diagnóstico por imagen , Brazo/irrigación sanguínea , Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/cirugía , Prótesis Vascular , Femenino , Estudios de Seguimiento , Humanos , Isquemia/etiología , Isquemia/cirugía , Arteria Subclavia/anomalías , Arteria Subclavia/cirugía , Trombectomía , Tromboembolia/diagnóstico por imagen
14.
Biomed Chromatogr ; 10(4): 167-71, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8831960

RESUMEN

Parameters affecting the separation of amino acids on different RP-HPLC columns were studied. Six amino acids were separated on Zorbax TMS, Zorbax CN, Zorbax ODS and Zorbax C8, using 1.8 x 10(-3) M copper sulphate at pH 4.1 as aqueous mobile phase. The best separation was shown by Zorbax TMS followed by Zorbax CN. The column performance was maintained by serial washing after 6 h continuous work with aqueous 10(-4) M disodium edetate, 10(-4) N sulphuric acid, water and gradient elution with aqueous methanol. The separation mechanism was interpreted. The method was applied for separation and quantification of aztreonam and L-arginine in Azactam vials.


Asunto(s)
Aminoácidos/análisis , Arginina/análisis , Aztreonam/análisis , Sulfato de Cobre/química , Monobactamas/análisis , Aminoácidos/química , Arginina/química , Aztreonam/química , Cromatografía Líquida de Alta Presión , Ácido Glutámico/análisis , Ácido Glutámico/química , Histidina/análisis , Histidina/química , Concentración de Iones de Hidrógeno , Modelos Lineales , Monobactamas/química , Ornitina/análisis , Ornitina/química , Fenilalanina/análisis , Fenilalanina/química , Espectrofotometría Ultravioleta , Treonina/análisis , Treonina/química , Agua/química
15.
Biomed Chromatogr ; 10(3): 131-4, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8792864

RESUMEN

A rapid and specific HPLC assay for quantiative determination of bupivacaine in human serum is described. The technique incorporates an on-line sample clean-up system followed by reversed-phase chromatography with UV detection. The proposed method uses a column-switching technique and protein-coated Lichrosorb RP-8 as a precolumn together with Lichrosorb RP-18 as an analytical column. The total run time for an injection of serum sample was 10 min. This procedure offers a sensitive assay without the need for time-consuming extractions. The average bupivacaine recoveries over a concentration range of 150-600 ng/mL ranged from 99.12 to 101.02%, and relative standard deviations ranged from 1.15 to 1.78%.


Asunto(s)
Anestésicos Locales/sangre , Bupivacaína/sangre , Cromatografía Líquida de Alta Presión/instrumentación , Adsorción , Análisis de Varianza , Anestésicos Locales/metabolismo , Proteínas Sanguíneas/metabolismo , Bupivacaína/metabolismo , Calibración , Cromatografía Líquida de Alta Presión/economía , Humanos , Modelos Lineales , Sistemas en Línea , Unión Proteica , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta , Factores de Tiempo
16.
J Assoc Off Anal Chem ; 73(4): 516-20, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2170322

RESUMEN

A rapid spectrophotometric procedure for the determination of isoprenaline salts, levodopa, dopamine hydrochloride, and dobutamine hydrochloride, either in the drug substances or in pharmaceutical formulations, is described. The method is based on the development of orange, red, or violet products with sodium metaperiodate in an aqueous alcoholic medium. The reaction is suggested to proceed via oxidative cyclization of the catecholamine to form an aminochrome. The wavelengths of maximum absorption range from 465 to 520 nm. The structure of the cyclization product was confirmed by ultraviolet, infrared, and nuclear magnetic resonance spectroscopy and microanalysis data.


Asunto(s)
Catecolaminas/análisis , Epinefrina/análisis , Concentración de Iones de Hidrógeno , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Ácido Peryódico , Polvos , Soluciones , Solventes , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Comprimidos
17.
Talanta ; 37(6): 625-7, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18964989

RESUMEN

A simple and accurate spectrophotometric method is described for the determination of epinephrine (EP), norepinephrine (NE) and their bitartrate salts. The method is based on the development of a red colour (lambda(max) 490 nm) with sodium periodate in aqueous alcoholic medium. The colour is stable for at least 1 hr. The molar reacting ratio of EP or NE to periodate is 1:2. The proposed method is particularly suitable for routine analysis of EP and NE injections. The interference due to the sodium metabisulphite normally used as antioxidant can be overcome by addition of acetone. Results for analysis of bulk drugs and injections agree well with those of official methods.

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