RESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: 'Ubtan' is a traditional herbal formulation in the Indian system of medicine being used in India and its subcontinent for a long time. Several commercial skin care formulations are marketed throughout this region as the name of Ubtan. Therefore, it is worthwhile to evaluate Ubtan in respect of its efficacy as skin care formulation. AIM OF THE STUDY: The present study was designed for the preparation of Ubtan and standardization through the chromatographic techniques by using suitable phyto-markers. Further, its antioxidant, sun protection factor (SPF) and anti-tyrosinase potential have been explored. MATERIALS AND METHODS: Four in-house formulations (UF-1, UF-2, UF-3 and UF-4) were prepared by mixing a varied quantity of each powdered plants, i.e. turmeric (Curcuma longa L.), Chickpea (Cicer arietinum L.) and sandalwood (Santalum album L.). Optimization of the formulations was made by evaluating its biological activity through in vitro assay. Evaluation of physicochemical properties of the optimized formulation (UF-1) has been carried out by analysis of pH, flow properties and stability. Moreover, RP-HPLC (reverse phase - high performance liquid chromatography) and HPTLC (high performance thin layer chromatography) standardization of UF-1 was performed for its quantitative and qualitative analysis. RESULTS: Ubtan formulations (UF-1to UF-4) showed free radical scavenging and ferric reducing potential. It may be due to its high phenolic and flavonoid content. Statistically, significant Pearson's correlation (r) was confirmed the positive correlation between phenolic content and SPF of the formulations. The tyrosinase inhibition study indicated that the formulations showed both diphenolase and monophenolase inhibitory activity. Among four formulations, UF-1 showed notable biological activity (p<0.05). The content of curcumin and ascorbic acid was found to be 1.6% and 2.1% w/w respectively in UF-1 through RP-HPLC estimation. Physiochemical properties of the UF-1 exhibited good flow rate and aqueous solubility. From the stability studies, it can be anticipated that the UF-1 was stable at 40°C for longer periods. Microbial load count and heavy metal content (lead-Pb, arsenic-As, mercury-Hg and cadmium-Cd) of the formulation was also within the permissible limit of a pharmacopeial standard. CONCLUSION: This scientific exploration helps to set the quality and safety standard of traditional cosmetic formulation, Ubtan and its further use as an herbal skin care product.
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Antioxidantes/farmacología , Curcumina/análogos & derivados , Fármacos Dermatológicos/farmacología , Inhibidores Enzimáticos/farmacología , Monofenol Monooxigenasa/antagonistas & inhibidores , Preparaciones de Plantas/farmacología , Cuidados de la Piel/métodos , Protectores Solares/farmacología , Antioxidantes/química , Antioxidantes/normas , Ácido Ascórbico/farmacología , Carga Bacteriana , Compuestos de Bifenilo/química , Cromatografía Líquida de Alta Presión , Cromatografía de Fase Inversa , Cromatografía en Capa Delgada , Cicer/química , Seguridad de Productos para el Consumidor , Curcuma/química , Curcumina/química , Curcumina/farmacología , Fármacos Dermatológicos/química , Fármacos Dermatológicos/normas , Relación Dosis-Respuesta a Droga , Composición de Medicamentos , Contaminación de Medicamentos , Estabilidad de Medicamentos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/normas , Ferricianuros/química , Concentración de Iones de Hidrógeno , India , Medicina Tradicional , Metales Pesados/análisis , Oxidación-Reducción , Fitoterapia , Picratos/química , Preparaciones de Plantas/química , Preparaciones de Plantas/normas , Plantas Medicinales , Polvos , Control de Calidad , Reología , Medición de Riesgo , Santalum/química , Cuidados de la Piel/normas , Solubilidad , Espectrofotometría Atómica , Espectrofotometría Ultravioleta , Protectores Solares/química , Protectores Solares/normasRESUMEN
OBJECTIVE: To evaluate use of cortisol concentration prior to ACTH stimulation (baseline) to monitor efficacy of twice-daily administration of trilostane to dogs with pituitary-dependent hyperadrenocorticism (PDH). DESIGN: Retrospective case series. ANIMALS: 22 dogs with PDH. PROCEDURES: The database of a veterinary hospital was searched to identify dogs with PDH that were treated with the FDA-approved veterinary formulation of trilostane twice daily between January 1, 2008, and December 31, 2012. For each dog, signalment and details regarding each hospital visit including comorbidities, electrolyte concentrations, and clinical signs were extracted from the record. For each ACTH stimulation test performed, the respective correlations between baseline cortisol concentration and the cortisol concentration after ACTH stimulation (ACTH-stimulated cortisol concentration) and resultant decision regarding trilostane dose adjustment were determined. Excessive suppression of cortisol production was defined as an ACTH-stimulated cortisol concentration < 2.0 µg/dL. The ability of various baseline cortisol concentrations to predict whether a dog had excessive suppression of cortisol production was determined. RESULTS: 109 ACTH stimulation tests were performed for the 22 dogs. A baseline cortisol concentration > 3.2 µg/dL predicted that ACTH-stimulated cortisol concentration would be ≥ 2.0 µg/dL with 100% certainty; however, 14 of 64 tests with a baseline cortisol concentration > 3.2 µg/dL had an ACTH-stimulated cortisol concentration ≤ 3.2 µg/dL, which was suggestive of inadequate adrenocortical cortisol reserves. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that baseline cortisol concentration should not be used as the sole monitoring tool for management of dogs with PDH treated with trilostane twice daily.
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Dihidrotestosterona/análogos & derivados , Enfermedades de los Perros/tratamiento farmacológico , Inhibidores Enzimáticos/administración & dosificación , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/veterinaria , Hormona Adrenocorticotrópica/administración & dosificación , Animales , Comorbilidad , Dihidrotestosterona/administración & dosificación , Dihidrotestosterona/normas , Enfermedades de los Perros/sangre , Enfermedades de los Perros/epidemiología , Perros , Inhibidores Enzimáticos/normas , Femenino , Hidrocortisona/sangre , Masculino , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/sangre , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/tratamiento farmacológico , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/epidemiología , Estudios RetrospectivosRESUMEN
Global cerebral ischemia and reperfusion (I/R) often result in high mortality. Free radicals play an important role in global cerebral I/R. Xanthine oxidoreductase (XOR) inhibitors, such as allopurinol, have been reported to protect tissues from damage caused by reactive oxygen species (ROS) by inhibiting its production through XOR inhibition. The recently introduced XOR inhibitor febuxostat, which is a more potent inhibitor than allopurinol, is expected to decrease free radical production more effectively. Here, we analyzed the effects of allopurinol and febuxostat in decreasing global severe cerebral I/R damage in mice. Mice were divided into three groups: a placebo group, an allopurinol group, and a febuxostat group. Pathological examinations, which were performed in each group in the CA1 and CA2 regions of the hippocampus 4 days after I/R surgery, revealed that there was a decrease in the number of neuronal cells in the 14-min occlusion model in both regions and that drugs that were administered to prevent this damage were not effective. The enzymatic activity was extremely low in the mouse brain, and XOR could not be detected in the nonischemic and ischemic mice brains with western blot analyses. Thus, one of the reasons for the decreased effectiveness of XOR inhibitors in controlling severe whole-brain ischemia in a mouse model was the low levels of expression of XOR in the mouse brain.
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Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/enzimología , Inhibidores Enzimáticos/farmacología , Fármacos Neuroprotectores/farmacología , Xantina Deshidrogenasa/metabolismo , Animales , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/normas , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
OBJECTIVES: To examine the use of supervised machine learning to identify biases in evidence selection and determine if citation information can predict favorable conclusions in reviews about neuraminidase inhibitors. STUDY DESIGN AND SETTING: Reviews of neuraminidase inhibitors published during January 2005 to May 2013 were identified by searching PubMed. In a blinded evaluation, the reviews were classified as favorable if investigators agreed that they supported the use of neuraminidase inhibitors for prophylaxis or treatment of influenza. Reference lists were used to identify all unique citations to primary articles. Three classification methods were tested for their ability to predict favorable conclusions using only citation information. RESULTS: Citations to 4,574 articles were identified in 152 reviews of neuraminidase inhibitors, and 93 (61%) of these reviews were graded as favorable. Primary articles describing drug resistance were among the citations that were underrepresented in favorable reviews. The most accurate classifier predicted favorable conclusions with 96.2% accuracy, using citations to only 24 of 4,574 articles. CONCLUSION: Favorable conclusions in reviews about neuraminidase inhibitors can be predicted using only information about the articles they cite. The approach highlights how evidence exclusion shapes conclusions in reviews and provides a method to evaluate citation practices in a corpus of reviews.
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Inteligencia Artificial , Inhibidores Enzimáticos/normas , Inhibidores Enzimáticos/uso terapéutico , Neuraminidasa/antagonistas & inhibidores , Publicaciones/estadística & datos numéricos , Sesgo de Selección , Humanos , Gripe Humana/tratamiento farmacológico , Proyectos de Investigación , Literatura de Revisión como AsuntoRESUMEN
BACKGROUND: Treating patients admitted to critical care with severe pneumonia requires timely intervention with an effective antibiotic. This reduces the risk of dying of pneumonia and minimises complications associated with a prolonged stay in critical care. OBJECTIVE: To compare the cost-effectiveness of meropenem 1 g/8 h with piperacillin/tazobactam 4.5 g/8 h for treating pneumonia in UK critical care. METHODS: A Markov model was built to estimate lifetime costs and quality-adjusted life years (QALYs) of using meropenem versus piperacillin/tazobactam to treat severe pneumonia. Estimates of effectiveness, utility weights and costs were obtained from published sources. Probabilistic sensitivity analysis was conducted to address uncertainty in the model results. RESULTS: Cost of treating a patient with severe pneumonia was estimated as £19,026 with meropenem and £19,978 with piperacillin/tazobactam, respectively. QALYs gained were 4.768 with meropenem and 4.654 with piperacillin/tazobactam. Probabilistic sensitivity analysis showed meropenem to be consistently less costly and more effective than piperacillin/tazobactam. CONCLUSION: The additional efficacy of meropenem translates into more patients surviving critical care and leaving this high-cost service more quickly than if they had been treated with piperacillin/tazobactam. As meropenem is more effective and less expensive than piperacillin/tazobactam at treating patients with severe pneumonia, it is the dominant treatment option.
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Antibacterianos/economía , Inhibidores Enzimáticos/economía , Ácido Penicilánico/análogos & derivados , Piperacilina/economía , Neumonía/tratamiento farmacológico , Neumonía/economía , Tienamicinas/economía , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Análisis Costo-Beneficio , Cuidados Críticos , Quimioterapia Combinada , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/normas , Femenino , Humanos , Masculino , Cadenas de Markov , Meropenem , Persona de Mediana Edad , Modelos Económicos , Ácido Penicilánico/administración & dosificación , Ácido Penicilánico/economía , Ácido Penicilánico/normas , Piperacilina/administración & dosificación , Piperacilina/normas , Años de Vida Ajustados por Calidad de Vida , Tazobactam , Tienamicinas/administración & dosificación , Tienamicinas/normas , Insuficiencia del Tratamiento , Reino UnidoRESUMEN
The aim of this study was to investigate the effectiveness of Photodynamic Therapy (PDT) using Methylene Blue (MB) as the photosensitizing compound and a Light-Emitting Diode (LED) in American cutaneous leishmaniasis (ACL). Hamsters were experimentally infected with Leishmania (Leishmania) amazonensis. After the development of the lesions in the footpad, the animals were treated with MB three times a week for 3 months. Ten minutes after each application of MB, the lesions were irradiated with LED for 1 h. The lesions were evaluated weekly by the measurement of the hamster footpad thickness. At the end of the treatment the parasitic load was quantified in the regional lymph node of the hamsters. The treatment promoted a decrease in the thickness of infected footpad (P=0.0001) and reduction in the parasitic load in the regional lymph node (P=0.0007) of the animals from group treated with MB+LED. PDT using MB+LED in ACL caused by L. amazonensis shows a strong photodynamic effect. This therapy is very promising, once it is an inexpensive system and the own patient can apply it in their wound and in their house without the need of technical assistance.
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Inhibidores Enzimáticos/uso terapéutico , Leishmania mexicana/efectos de los fármacos , Leishmaniasis Cutánea/tratamiento farmacológico , Azul de Metileno/uso terapéutico , Fotoquimioterapia/métodos , Animales , Cricetinae , Inhibidores Enzimáticos/normas , Ganglios Linfáticos/parasitología , Masculino , Mesocricetus , Azul de Metileno/normas , Fotoquimioterapia/normas , Bazo/parasitologíaRESUMEN
PURPOSE: Miglustat (Zavesca) is an orally-available substrate reduction therapy (SRT) for treatment of mild-to-moderate type 1 Gaucher disease (GD1) in adult patients unsuitable for enzyme replacement therapy (ERT). Miglustat has not been evaluated in children with GD1, and is not used during pregnancy and breast-feeding. A non-interventional, prospective, web-based safety surveillance programme was initiated at the time of the European launch of miglustat in 2003, and is ongoing. We report the first 5 years of collected data, focusing on neurological manifestations. METHODS: Data were collected on 122 GD1 patients between March 2003 and April 2008, representing 244 patient-years cumulative miglustat post-authorisation experience. The electronically-captured data collected from participating physicians includes patient demographics, prior and current therapies, baseline disease manifestations and concurrent conditions, disease severity, duration of miglustat exposure, and safety-relevant information. RESULTS: Mean (SD) age at baseline was 46.1 (16.5) years. At baseline, bone disease and neurological manifestations were reported in 55.6 and 28.6% of patients, respectively; the latter included peripheral neuropathy (7.2%) and a wide variety of neurological symptoms and signs. In addition, 23.2% had other health conditions relevant to neurological status. During the reporting period, new neurological manifestations were reported in 23 (18.9%) patients, principally tremor. Thirty-five (28.7%) patients discontinued treatment, predominantly for gastrointestinal (GI) disturbances (11.5%), two-thirds of which occurred during the first 6 months. CONCLUSION: The safety profile of miglustat in GD1 patients included in the safety surveillance programme is overall consistent with that reported in the registration and other clinical trials, and no new safety finding was identified.
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1-Desoxinojirimicina/análogos & derivados , Inhibidores Enzimáticos/uso terapéutico , Enfermedad de Gaucher/tratamiento farmacológico , 1-Desoxinojirimicina/efectos adversos , 1-Desoxinojirimicina/normas , 1-Desoxinojirimicina/uso terapéutico , Adolescente , Adulto , Anciano , Niño , Preescolar , Inhibidores Enzimáticos/efectos adversos , Inhibidores Enzimáticos/normas , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/inducido químicamente , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
Nitric oxide (NO) is one of the most important mediators and neurotransmitters and its levels change under pathological conditions. NO production may be regulated by endogenous nitric oxide synthase (NOS) inhibitors, in particular asymmetric dimethylarginine (ADMA). Most of the interest is focused on ADMA, since this compound is present in plasma and urine and accumulation of ADMA has been described in many disease states but little is known about cerebrospinal fluid (CSF) concentrations of this compound and of its structural isomer symmetric dimethylarginine (SDMA). To determine the levels of methylarginines, we here present a new hydrophilic interaction chromatography (HILIC)-MS/MS method for the precise determination of these substances in CSF from microdialysis samples of rat prefrontal cortex (PFC). The method requires only minimal sample preparation and features isotope-labelled internal standards.
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Arginina/análogos & derivados , Cromatografía Liquida/métodos , Microdiálisis/métodos , Espectrometría de Masas en Tándem/métodos , Animales , Arginina/líquido cefalorraquídeo , Arginina/normas , Inhibidores Enzimáticos/líquido cefalorraquídeo , Inhibidores Enzimáticos/normas , Óxido Nítrico Sintasa/antagonistas & inhibidores , Corteza Prefrontal/química , Ratas , Ratas Wistar , Estándares de ReferenciaRESUMEN
The quality of the data generated in a high throughput screening (HTS) run is fundamental for selecting bona fide inhibitors and for ensuring the capture of the full richness of inhibitors present in a chemical library. For this purpose a quality control filter based on three one dimensional (1D) proton NMR experiments is proposed. The approach called SPAM (Solubility, Purity and Aggregation of the Molecule) Filter requires the acquisition of a 1D reference spectrum, a WaterLOGSY spectrum and/or a selective longitudinal relaxation filter spectrum for the identified hits dissolved in aqueous solution and in the presence of a water soluble reference molecule. This palette of experiments permits the rapid characterization of the identity, purity, solubility and aggregation state of the active compound. This knowledge is crucial for deriving accurate IC(50) and K(1) values of the inhibitors, for identifying false negatives and for detecting promiscuous inhibitors. Only compounds that pass through the SPAM Filter can be considered as starting points for medicinal chemistry efforts directed toward lead optimization. Examples of this approach in the identification of false positives in a screening run against the enzyme thymidine phosphorylase (TP) and the rescue of a false negative in a screening run against the Ser/Thr kinase AKT1 are presented.
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Inhibidores Enzimáticos/química , Espectroscopía de Resonancia Magnética/métodos , Tecnología Farmacéutica/métodos , Algoritmos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/normas , Humanos , Concentración 50 Inhibidora , Isoquinolinas/química , Isoquinolinas/farmacología , Estructura Molecular , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Control de Calidad , Quercetina/química , Quercetina/farmacología , Solubilidad , Relación Estructura-Actividad , Sulfonamidas/química , Sulfonamidas/farmacología , Tecnología Farmacéutica/tendencias , Timidina Fosforilasa/antagonistas & inhibidores , Timidina Fosforilasa/metabolismoRESUMEN
The design of studies to evaluate the efficacy of acid-lowering drugs in children differs significantly from study designs in adult populations. Efficacy measurements may be less extensive than those used in adult studies because of limitations that exist secondary to concerns for patient safety, parental and institutional review board acceptance of efficacy end points, and existing standards of care within the pediatric gastroenterology community. Study designs involving patients who would routinely receive acid-lowering therapy have been successfully used to characterize the pharmacokinetics and pharmacodynamics of acid-lowering therapies (H2 receptor antagonists) and have led to pediatric labeling for these drugs. This approach may likewise be used in the study of newer acid-lowering agents, such as proton pump inhibitors.
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Inhibidores Enzimáticos/uso terapéutico , Determinación de la Acidez Gástrica , Inhibidores de la Bomba de Protones , Adolescente , Antiulcerosos/farmacocinética , Antiulcerosos/normas , Antiulcerosos/uso terapéutico , Niño , Preescolar , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/normas , Antagonistas de los Receptores H2 de la Histamina/farmacocinética , Antagonistas de los Receptores H2 de la Histamina/normas , Antagonistas de los Receptores H2 de la Histamina/uso terapéutico , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Seguridad , Resultado del TratamientoRESUMEN
This article compares the Swedish Medical Products Agency's (MPA) decision to switch omeprazole from prescription (Rx) to over-the-counter (OTC) status with the US Food and Drug Administration (FDA) advisory panel's decision not to authorize the switch. The agencies' differing perspectives on efficacy, safety, labeling, and clinical trial requirements are evaluated with regard to the Rx-to-OTC switch process in general and omeprazole's case in particular. The FDA and MPA regulatory policies on switches are substantially divergent. The FDA maintains a stricter set of switch guidelines and requirements than the MPA. One could infer from this that the FDA is more risk-averse than the MPA. Nevertheless, the omeprazole switch in Sweden appears to be an exception in that it contrasts with the MPA's historical reluctance to switch the Rx status of medications. Cost considerations appear to have triggered the omeprazole switch, making it a special case. The lessons to be drawn from this case study are both specific and general. At the specific level, this case study suggests the MPA's decision to switch omeprazole was prompted by economic considerations, whereas the FDA's mandate did not allow cost to affect its decision on omeprazole. At a general level, this case study indicates that the differences between the FDA and MPA with respect to their regulatory policies on switches and their mandates apply not only to omeprazole but also to the dozens of switches currently under consideration by the respective regulatory agencies.
Asunto(s)
Antiulcerosos , Aprobación de Drogas/organización & administración , Costos de los Medicamentos/normas , Inhibidores Enzimáticos , Medicamentos sin Prescripción , Omeprazol , Antiulcerosos/economía , Antiulcerosos/normas , Antiulcerosos/uso terapéutico , Toma de Decisiones en la Organización , Prescripciones de Medicamentos/economía , Inhibidores Enzimáticos/economía , Inhibidores Enzimáticos/normas , Inhibidores Enzimáticos/uso terapéutico , Humanos , Medicamentos sin Prescripción/economía , Medicamentos sin Prescripción/normas , Medicamentos sin Prescripción/uso terapéutico , Omeprazol/economía , Omeprazol/normas , Omeprazol/uso terapéutico , Garantía de la Calidad de Atención de Salud , Suecia , Estados Unidos , United States Food and Drug Administration/normasRESUMEN
Patients with malignant glioma continue to have a dismal outcome. Those with glioblastoma multiforme, the most common type of malignant glioma, have a median survival of 40 to 60 weeks following diagnosis and only 16 to 24 weeks after recurrence. While standard therapy is surgery and external-beam radiotherapy, data indicate that chemotherapy improves the clinical outcome of some patients. Irinotecan (CPT-11, Camptosar) possesses significant activity against malignant glioma, and potentiation of this activity with combination partners, including the alkylator 1,2-bis(2-chloroethyl)-1-nitrosourea (carmustine, BCNU), is being evaluated in an ongoing phase II study. Also, the combination of irinotecan plus temozolomide (Temodar) has produced synergism in preclinical studies as well as encouraging responses in ongoing clinical trials. Other investigative directions include studies of irinotecan plus temozolomide and O6-benzylguanine (O6-BG) to assess the ability of O6-BG to maximize the therapeutic benefits of irinotecan combined with temozolomide.
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Antineoplásicos Fitogénicos/uso terapéutico , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Animales , Antimetabolitos Antineoplásicos/uso terapéutico , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/normas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Camptotecina/administración & dosificación , Camptotecina/normas , Neoplasias Colorrectales/tratamiento farmacológico , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/normas , Fluorouracilo/uso terapéutico , Glioma/tratamiento farmacológico , Humanos , Irinotecán , Estados UnidosAsunto(s)
Neoplasias/tratamiento farmacológico , Neoplasias/fisiopatología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Antineoplásicos/normas , Antineoplásicos/uso terapéutico , Ensayos Clínicos como Asunto , Inhibidores Enzimáticos/normas , Inhibidores Enzimáticos/uso terapéutico , Receptores ErbB/efectos de los fármacos , Gefitinib , Conocimientos, Actitudes y Práctica en Salud , Humanos , Quinazolinas/normas , Quinazolinas/uso terapéutico , Estados Unidos , Receptor 2 de Factores de Crecimiento Endotelial Vascular/efectos de los fármacosRESUMEN
Alcoholic extracts from the herb "St. John's wort" (Hypericum perforatum L.) are widely used to counteract depressive situations, where the question on the mainly active principle is still under discussion. Thus, standardization of the drug on the basis of dry matter has been chosen instead of the popular leading component, hypericin. Inhibition of myeloperoxidase-catalyzed dimerization of enkephalins by Hypericum extracts has recently been reported. This method is based on the separation and quantification of enkephalin dimers by HPLC. In order to simplify this assay myeloperoxidase could be substituted by the cheaper horseradish peroxidase and the enkephalins by the amino acid tyrosine without loss of significance. In this communication we represent a more rapid photometric method based on peroxidase-catalyzed indole acetic acid oxidation suitable for quick, simple and economic drug standardization.
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Inhibidores Enzimáticos/farmacología , Ericales/química , Peroxidasa/antagonistas & inhibidores , Cromatografía Líquida de Alta Presión , Dimerización , Inhibidores Enzimáticos/normas , Ericales/crecimiento & desarrollo , Fertilizantes , Peroxidasa de Rábano Silvestre/metabolismo , Peróxido de Hidrógeno , Ácidos Indolacéticos/química , Oxidantes , Oxidación-Reducción , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/normas , Tirosina/químicaRESUMEN
Marketing of medicinal plants and phytotherapeutic products is spreading all over the world. In order to assess the commercialization of medicinal plants and phytotherapeutic products in the State of Minas Gerais, we identified and tested for the presence of adulterants and active ingredients in 27 samples of chamomile. All the samples consisted of Matricaria recutita flowers, but they were badly fragmented, a result of excessive handling and poor preservation. All samples contained contaminants, and insects were observed in 63% of the samples sold in drugstores. Only 50% of the samples in each group had the essential oils needed to produce antiinflammatory activity. Flavonoids and other phenolic constituents with a spasmolytic effect were detected in only 20% of the samples from each group. Results with chamomile indicated the poor quality with which medicinal plants and phytotherapeutic products are marketed and confirm the need for surveillance of such products in Brazil.
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Anticarcinógenos/normas , Inhibidores Enzimáticos/normas , Flavonoides/normas , Hialuronoglucosaminidasa/antagonistas & inhibidores , Aceites Volátiles/normas , Fitoterapia , Brasil , Manzanilla , Contaminación de Medicamentos/prevención & control , Plantas Medicinales , Vigilancia de Productos ComercializadosRESUMEN
Pyrimethamine is an antiparasitic agent currently used for therapy of central nervous system toxoplasmosis, a disease seen with increasing frequency in association with the AIDS epidemic. Monitoring of pyrimethamine levels may be particularly important because patients may be treated with high doses of the drug for extended periods of time. The authors have developed and validated both a new enzyme inhibition assay that can be run on an automated analyzer and an improved high performance liquid chromatography (HPLC) method. The calibration range of both methods is 100 to 3,000 micrograms/L. Both demonstrate good linearity, specificity, and precision, and correlate well with one another (r = 0.99). The CVs of the enzyme inhibition assay were < or = 8.6% and those of the HPLC method were < or = 5.4%. No interference was noted for a variety of drugs likely to be used concomitantly with or in lieu of pyrimethamine with the exception of a minor interference from trimethoprim in the enzyme inhibition assay. The major advantage of the enzyme inhibition assay is its ease of automation. The major advantages of the HPLC assay are its precision and relative simplicity. These methods should facilitate therapeutic monitoring of pyrimethamine.