RESUMEN
Primary renal marginal zone B lymphoma is extremely rare. The renal involvement by the lymphoma is most often a manifestation of a disseminated disease. We report the case of a 53-year-old patient who presented lower back pain and kidney failure. The renal biopsy showed a marginal zone B lymphoma type MALT and the PET scan showed bilateral renal involvement. A treatment based on rituximab combined with chemotherapy (cyclophosphamide, prednisone and oncovin) was started with good outcome.
Le lymphome B de la zone marginale rénale comme lésion primitive est extrêmement rare car l'atteinte rénale est le plus souvent une manifestation de la maladie disséminée. Nous rapportons le cas d'un patient âgé de 53 ans présentant des lombalgies chroniques avec insuffisance rénale. La biopsie rénale était en faveur d'un lymphome B de la zone marginale type MALT et la tomographie par émission de positons a objectivé une atteinte rénale bilatérale. Un traitement à base de rituximab couplé à une chimiothérapie (cyclophosphamide, prednisone et oncovin) a été démarré avec une bonne évolution.
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Linfoma de Células B de la Zona Marginal , Humanos , Persona de Mediana Edad , Rituximab/uso terapéutico , Ciclofosfamida/uso terapéutico , Vincristina/uso terapéutico , Prednisona/uso terapéutico , Linfoma de Células B de la Zona Marginal/diagnóstico , Linfoma de Células B de la Zona Marginal/tratamiento farmacológico , Linfoma de Células B de la Zona Marginal/patología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéuticoRESUMEN
Bisphenols A (BPA) and S (BPS) are endocrine-disrupting chemicals that affect energy metabolism, leading to impairment of glucose and lipid homeostasis. We aimed at identifying metabolic pathways regulated by both compounds in human liver cells and rat pancreatic ß-cells that could impair energy homeostasis regulation. We assessed the effects on growth, proliferation, and viability of hepatocarcinoma (HepG2) and insulinoma (INS-1E) cells exposed to either BPA or BPS in a full range concentration between 0.001 and 100 µM. Both the dose and duration of exposure caused a differential response on growth and viability of both cells. Effects were more pronounced on HepG2, as these cells exhibited non-linear dose-responses following exposure to xenobiotics. For INS-1E, effect was observed only at the highest concentration. In addition, we profiled their intracellular state by untargeted metabolomics at 24, 48, and 72 h of exposure. This analysis revealed time- and dose-dependently molecular changes for HepG2 and INS-1E that were similar between BPA and BPS. Both increased levels of inflammatory mediators, such as metabolites pertaining to linolenic and linoleic acid metabolic pathway. In summary, this study shows that BPS also disrupts molecular functions in cells that regulate energy homeostasis, displaying similar but less pronounced responses than BPA.
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Disruptores Endocrinos , Plastificantes , Animales , Compuestos de Bencidrilo/química , Compuestos de Bencidrilo/toxicidad , Disruptores Endocrinos/química , Disruptores Endocrinos/toxicidad , Glucosa , Humanos , Metabolómica , Ratas , SulfonasRESUMEN
PURPOSE: New techniques are needed to speed-up the identification and antimicrobial susceptibility testing (AST) of bacteria associated with bloodstream infections. Alfred 60/AST (Alifax®, Polverara, Italy) performs AST by light scattering directly from positive blood cultures. METHODS: We evaluated Alfred 60/AST performances for 4 months. Each new episode of bacteraemia was included and AST were compared to either our rapid automated AST (Vitek® 2) or disk diffusion method. The discrepancies were investigated using Etest®. The time-to-result (TTR) was evaluated by comparing the blood volume inserted into Alfred 60/AST, i.e. 2 versus 7 blood drops. Taking into account the TTR, the workflow of positive blood cultures and the availability of AST results was studied in order to optimize the implementation of Alfred 60/AST. RESULTS: A total of 249 samples and 1108 antibiotics for AST were tested. After exclusion of unavailable results, 1008 antibiotics were analysed. 94.9% (n = 957/1008) of the antibiotics showed categorical agreement. There were 14 very major errors (VME), 24 major errors (ME) and 13 minor errors (mE). The VME were mostly related to clindamycin (64.3%) whereas meropenem and piperacillin-tazobactam constituted the major part (37.5% and 61.5%) of ME and mE respectively. Results were highly reliable for Enterobacterales and enterococci. The mean TTR ranged between 4.3 and 6.3 h and was statistically 20 min faster when applying the 7 blood drops protocol. We showed that Alfred 60/AST could give relievable results within working hours for positive blood culture which are flagged the same day between 12:00 am and 12:00 pm. CONCLUSION: Our study confirmed that Alfred 60/AST gives reliable AST results in a short period of time, especially for Enterobacterales and enterococci. AST could thus be easily obtained the same day of a positive blood culture. Clinical impact studies are mandatory to validate a 24/24 working.
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Bacteriemia , Gammaproteobacteria , Antibacterianos/farmacología , Bacteriemia/microbiología , Cultivo de Sangre/métodos , Bacterias Gramnegativas , Humanos , Pruebas de Sensibilidad Microbiana , Flujo de TrabajoRESUMEN
According to the World Health Organization, medulloepithelioma belongs to the embryonal neoplasm entity. It is a very rare, highly malignant tumor typically affecting infants and young children. Usually, the tumor arises in the eye or in the central nervous system; a peripheral location has been rarely reported without an established treatment. The recognition and separation of this neoplasm from other differential tumors are mandatory for better understanding of its biology and determination of optimal treatment. This paper reports a case of an ectopic intrapelvic medulloepithelioma with liver metastasis in a 3-year-old girl.
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Treatment of acute myeloblastic leukemia in children, adolescents and young adults (AYA) is a challenge in low-income countries. To evaluate treatment outcomes of children (≤ 15 years) and AYA (15-30 years) diagnosed with novo AML and treated in a single center according to the AML-MA 2011 protocol. From January 2011 to December 2015, eligible patients (age ≤ 30 years) with novo AML had been enrolled on a uniform treatment protocol. The diagnosis was confirmed according to the FAB classification using the WHO 2008 criteria. Patients with WBC ≥ 50 G/L had pretreated 4 days of hydroxyurea followed by two inductions and two consolidations. Supportive care consisted of transfusion of labile blood products, antibiotics and antifungals, and patient and family education by the hygiene team. 155 patients were recruited, 41 were < 15 years old (22 boys, median age 7.8 years). Of the 114 AYA enrolled, (48 women, median age 23 years). Complete remission after two inductions was 28/41 (68.3%) of the children, including 100% of the children in the favorable group and 71/114 (62.3%) of the AYA, 22 of whom (68.7%) were in the favorable group. The number of deaths among children was 6 (14.6%). The evaluation of the AML-MA-2011 National Protocol in the age groups of children and AYA reveals that the objective of treatment is almost achieved in terms of complete remission in the two age groups.
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Assessment of the effectiveness of nature conservation measures is a crucial step to ensure that the actions undertaken have achieved the expected results. Depending on the results of such evaluations, managers may need to reframe or even change their approaches. In this analysis, the effectiveness of establishing strictly protected areas was assessed in three important Moroccan Atlantic sites, namely Ad-Dakhla bay, Khnifiss lagoon, and Souss estuary. In particular, we investigated whether protection of these sites was followed by significant changes in the direction and/or strength of change in waterbird species richness and density over time. Our results showed that during the pre-protection period, waterbird species richness has been declining over time, while total waterbird density and the diversity of wading and open-water birds had been maintained at low levels. However, shortly after site protection, a rapid increase in these measures was observed, while there was no significant change in waterfowl species richness and density. Overall, these results suggest that the protection of these wetlands has been a watershed in the recent history of their birds, reversing the trends of a continuing decline towards rapid regeneration. This is one obvious signs of the success of the programme undertaken by the Moroccan authorities to conserve the biodiversity of these wetlands. Further investigations of the effects of protection at all wetlands throughout Morocco are needed to more profoundly understand the role of such conservation measures on shaping wintering waterbird communities.
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Biodiversidad , Aves/clasificación , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente/métodos , Animales , Marruecos , Estaciones del Año , HumedalesRESUMEN
INTRODUCTION: The goal of this study is to assess functional and aesthetic results of anterior lamellar resection with lid margin splitting of the upper lid in the treatment of cicatricial trachomatous entropion. PATIENTS AND METHODS: Descriptive cross-sectional study of a series of 26 consecutive patients treated between January 2014 and December 2015. All patients were operated for cicatricial trachomatous entropion in our tertiary center using the technique of the anterior lamellar resection with lid margin splitting of the upper eyelid. All patients were followed for 6 to 12 months after surgery. The anatomical, functional and aesthetic results were evaluated six months after surgery. They were considered good if there was no recurrence of the entropion, no lashes in contact with the cornea and no associated eyelid complications. RESULTS: The mean age of the patients was 68.5±10 years with a male predominance (sex ratio=1.8). The average initial corrected visual acuity was 0.65±0.35 LogMAR, ranging from counting fingers at 1m to 6/10. Involvement was bilateral in 34.6% of cases. Correction of the cicatricial entropion was achieved in 24 patients (92.3% of cases) and full correction of misdirected lashes without any contact with the ocular surface was obtained in 23 patients (88.4% of cases). The lid margin was regular in 88.4% of cases. A significant improvement of the tear film and corneal surface was observed in 84.6% of patients. During the follow-up period, no cases of recurrent entropion were reported. DISCUSSION: Among the various surgical techniques, anterior lamellar resection with lid margin splitting is one that most respects the anatomy of the upper eyelid and allows precise intraoperative control of eyelid rotation and eversion of the misdirected lashes. Therefore, it reduces significantly the risk of recurrence and significantly enhances the aesthetic results of surgery. CONCLUSION: Anterior lamellar resection with lid margin splitting of the upper eyelid is a simple and effective technique that significantly improves the aesthetic result of cicatricial trachomatous entropion.
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Entropión/cirugía , Enfermedades de los Párpados/cirugía , Procedimientos Quirúrgicos Oftalmológicos/métodos , Tracoma/cirugía , Anciano , Cicatriz/cirugía , Estudios Transversales , Entropión/complicaciones , Párpados/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tracoma/complicaciones , Agudeza VisualRESUMEN
PURPOSE: To evaluate the aesthetic and functional results of the Köllner-Hughes tarsoconjonctival flap technique for large defects of over three-quarter of the lower eyelid. PATIENTS AND METHODS: A retrospective descriptive study of a series of 15 patients treated between January 2013 and December 2015. We included all patients who underwent reconstructive surgery for a tumor involving more than three-quarter of the lower eyelid and sparing the canthi. Reconstruction of the lower eyelid defect was performed using Köllner-Hughes technique. RESULTS: The mean age of our patients was 65.7±8 years. The sex ratio was 1.5 with male predominance. All patients had well-differentiated basal cell carcinoma of the lower eyelid. The average size of the eyelid defect induced by the surgery was 18±4mm. Release of the tarsoconjonctival flap was performed after a period of 8 to 10 weeks after the reconstructive surgery. After a mean follow-up of 12±6 months, the aesthetic and functional results were satisfactory in 86.7% of cases especially in terms of eyelid closure and protection of the ocular surface. Complications included erythema of the newly formed free edge in 26.7% of cases, keratinization and hypertrophy of the free edge in 20% of cases, the deformation of the upper free edge with an associated entropion in 20% of cases and lower eyelid retraction in 6.67% of cases. Ocular surface disease such assuperficial punctate keratitis or dry eye was found in 13.4% of cases. DISCUSSION: Several authors have chosen the Köllner-Hughes technique to treat increasingly wide eyelid defects with very satisfactory results. Eyelid reconstruction with the Köllner and Hughes technique is a very attractive procedure because it offers several advantages. It is a quick and easy technique that covers wide defects over three-quarter of the lower eyelid well with very satisfactory cosmetic results and without significantly increasing morbidity at the donor site. In combination with additional procedures, this technique can totally reconstruct the lower eyelid. Despite all its benefits, the Köllner-Hughes tarsoconjonctival flap has some minor drawbacks, such as the need for two surgeries spaced a few weeks apart to open the palpebral fissure; therefore it is contraindicated for one-eyed patients and children because of the risk of amblyopia. CONCLUSION: The tarsoconjonctival flap as initially described by Köllner and Hughes was indicated in the reconstruction of moderate and medium-sized defects of the lower eyelid. In our practice, we can extend the indications of this technique to much larger defects than three-quarter of the lower eyelid, while ensuring satisfactory aesthetic results and minimal complications.
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Blefaroplastia/métodos , Enfermedades de los Párpados/cirugía , Procedimientos de Cirugía Plástica/métodos , Trasplante de Piel/métodos , Colgajos Quirúrgicos/fisiología , Anciano , Carcinoma Basocelular/patología , Carcinoma Basocelular/cirugía , Conjuntiva/patología , Neoplasias de los Párpados/patología , Neoplasias de los Párpados/cirugía , Párpados/patología , Párpados/cirugía , Párpados/trasplante , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
INTRODUCTION: The prevalence of pseudoexfoliation syndrome is estimated at 8 % of all cataracts operated within our institution. The goal of our study was to describe the frequency of intraoperative and postoperative complications and long-term anatomical and functional results of phacoemulsification in pseudoexfoliation syndrome. PATIENTS AND METHODS: A retrospective observational study of a series including 103 patients (107 eyes) with cataract associated with pseudoexfoliation syndrome admitted between January 2010 and September 2014. All patients underwent phacoemulsification. RESULTS: The average age of our patients was 72.5±6 years. The average initial corrected visual acuity was 0.52±0.14LogMAR. The cataract was grade C3N3 in 58 % of cases. The pseudoexfoliation syndrome was bilateral in 69 % of cases. Pupillary dilatation was≤6mm in 54 % of cases. Among intraoperative complications, zonular dialysis was found in 1.8 % of cases. Posterior capsular rupture and vitreous loss was noted at 5.4 % of patients. The incidence of secondary cataract was 31.7 % at 12 months. The mean postoperative best corrected visual acuity was 0.13±0.15 LogMAR. DISCUSSION: The small pupil associated with high grade of the cataracts in our series explains the slightly higher frequency of intraoperative zonular dialysis. Cataract surgery by phacoemulsification allows for a statistically significant improvement in visual acuity (P<0.001). The incidence of secondary cataract, the main postoperative complication, is higher in our series compared to data in the literature. CONCLUSION: Pseudoexfoliation syndrome is common in our country. Functional results of phacoemulsification are very satisfactory, and secondary cataract is the main complication. A meticulous search for pseudoexfoliation is mandatory during the initial examination in order to reduce intraoperative complications. Careful removal of the cortex and systematic polishing of the lens capsule should limit the incidence of secondary cataracts.
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Síndrome de Exfoliación/cirugía , Complicaciones Intraoperatorias/epidemiología , Facoemulsificación/efectos adversos , Complicaciones Posoperatorias/epidemiología , Anciano , Catarata/complicaciones , Catarata/epidemiología , Extracción de Catarata/efectos adversos , Extracción de Catarata/estadística & datos numéricos , Síndrome de Exfoliación/complicaciones , Síndrome de Exfoliación/epidemiología , Femenino , Humanos , Incidencia , Masculino , Facoemulsificación/estadística & datos numéricos , Estudios Retrospectivos , Agudeza VisualRESUMEN
Prompt epinephrine administration is crucial in managing anaphylaxis, but epinephrine auto-injectors (EAIs) are underutilized by patients and their families. Children with peanut allergy were recruited from the Allergy Clinics at the Montreal Children's Hospital, food allergy advocacy organizations and organizations providing products to allergic individuals. Parents of children who had been prescribed an EAI were queried on whether they were fearful of using it and on factors that may contribute to fear. A majority of parents (672/1209 = 56%) expressed fear regarding the use of the EAI. Parents attributed the fear to hurting the child, using the EAI incorrectly or a bad outcome. Parents whose child had longer disease duration or a severe reaction and parents who were satisfied with the EAI training or found it easy to use were less likely to be afraid. Families may benefit from simulation training and more education on the recognition and management of anaphylaxis.
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Epinefrina/administración & dosificación , Miedo , Hipersensibilidad al Cacahuete/tratamiento farmacológico , Hipersensibilidad al Cacahuete/psicología , Adolescente , Anafilaxia/prevención & control , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Inyecciones Intramusculares , Masculino , Hipersensibilidad al Cacahuete/epidemiología , Factores de RiesgoRESUMEN
Due to their high specificity and efficiency, antibodies are ideal ligands for target-specific ultrasound contrast agents. The present study focuses on the chemical stability of antibodies during functionalisation with sulfosuccinimidyl-pyridyldithiopropionamidohexanoate (SPDP), a heterobifunctional linker, which exposes free thiol groups upon treatment with a reducing agent. Thiolated antibodies can then react with thiol-reactive group, such as maleimide present on the microbubble surface to form stable covalent complexes. The immunoglobulin structure relies on several intra- and inter-chain disulfide bridges which might be affected by reducing agents. A capillary electrophoresis-sodium dodecyl sulfate (CE-SDS) method with UV detection was applied to address the effect of the functionalisation process on the structural integrity of the antibodies and revealed that antibody disulfide bonds are prone to reduction as function of the reducing agents. Depending on the coupling conditions, various IgG fragments were identified reflecting different combinations between the light and heavy chains. Furthermore, two commonly used reducing agents, namely triscarboxyethylphosphine (TCEP) and 1,4-dithiothreitol (DTT) were compared under various preparation conditions. Results showed that reduction conditions based on DTT as a reducing agent under acidic pH were more appropriate to preserve intra- and inter-disulfide bridges of SPDP-modified antibodies.
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Anticuerpos/química , Sistemas de Liberación de Medicamentos/métodos , Electroforesis Capilar/métodos , Fragmentos de Inmunoglobulinas/química , Microburbujas , Medios de Contraste/química , Ditiotreitol/química , Inmunoglobulina G/análisis , Maleimidas/química , Oxidación-Reducción , Fosfinas/química , Succinimidas/químicaRESUMEN
The transition of a targeted ultrasound contrast agent from animal imaging to testing in clinical studies requires considerable chemical development. The nature of the construct changes from an agent that is chemically attached to microbubbles to one where the targeting group is coupled to a phospholipid, for direct incorporation to the bubble surface. We provide an efficient method to attach a heterodimeric peptide to a pegylated phospholipid and show that the resulting construct retains nanomolar affinity for its target, vascular endothelial growth factor receptor 2 (VEGFR2), for both the human (kinase insert domain-containing receptor - KDR) and the mouse (fetal liver kinase 1 - Flk-1) receptors. The purified phospholipid-PEG-peptide isolated from TFA-based eluents is not stable with respect to hydrolysis of the fatty ester moieties. This leads to the time-dependent formation of the lysophospholipid and the phosphoglycerylamide derived from the degradation of the product. Purification of the product using neutral eluent systems provides a stable product. Methods to prepare the lysophospholipid (hydrolysis product) are also included. Biacore binding data demonstrated the retention of binding of the lipopeptide to the KDR receptor. The phospholipid-PEG2000-peptide is smoothly incorporated into gas-filled microbubbles and provides imaging of angiogenesis in a rat tumor model.
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Neoplasias Mamarias Animales/irrigación sanguínea , Neovascularización Patológica/diagnóstico por imagen , Péptidos , Fosfolípidos , Polietilenglicoles , Ultrasonografía , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Neoplasias Mamarias Animales/metabolismo , Ratones , Estructura Molecular , Neovascularización Patológica/patología , Péptidos/química , Fosfolípidos/química , Polietilenglicoles/química , Ratas , Ratas Endogámicas F344RESUMEN
Dextromethorphan (DEM) is a widely used probe drug for human cytochrome P450 2D6 isozyme activity assessment by measuring the ratio between DEM and its N-demethylated metabolite dextrorphan (DOR). DOR is excreted in urine mainly conjugated to glucuronic acid. Prior to quantification, DOR must be deconjugated to avoid variability caused by the polymorphic glucuronosyltransferase enzyme. A chemical hydrolysis method was optimized using a chemometric approach. Three factors (acid concentration, hydrolysis time and temperature) were selected and simultaneously varied to study their effect on conjugated DOR hydrolysis. Hydrolysis conditions that maximize DOR release without significant degradation of both DEM and DOR were chosen and results were compared to those obtained by enzymatic method using beta-glucuronidase. An HPLC method with fluorescence detection was developed for the simultaneous quantitation of DEM, DOR and levallorphan, used as an internal standard. Separation was performed on a phenyl analytical column (150 mmx4.6 mm i.d., 5 microm) with a mobile phase consisting of 18% acetonitrile and 50 mM phosphoric acid (pH 3). The overall analytical procedure was validated and showed good performances in terms of selectivity, linearity, sensitivity, precision and accuracy. Finally, this assay was used to determine DEM/DOR molar ratios in fibromyalgia patients for the purpose of determining phenotype status for the CYP2D6.
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Citocromo P-450 CYP2D6/metabolismo , Dextrometorfano/orina , Dextrorfano/orina , Fibromialgia/orina , Dextrometorfano/química , Dextrometorfano/metabolismo , Dextrorfano/química , Dextrorfano/metabolismo , Fibromialgia/metabolismo , Humanos , Hidrólisis , Reproducibilidad de los ResultadosRESUMEN
Willebrand's disease is the most frequent inborn coagulopathy and type 3 is its most severe form. Pregnancy and delivery are critical events in women with Willebrand's disease of type 3. Prophylactic treatment for delivery and early postpartum period is recommended. We report the management of pregnancy and successful delivery of a 32-year-old woman with type 3. Prophylactic treatment with 2000 IU of Willebrand's disease factor (WdF) was given twice a day during the delivery day and the day after, and 1000 IU per day during the next three days. The patient did not show any spontaneous metrorrhagia but anemia. No bleeding was observed in the newborn.
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Pérdida de Sangre Quirúrgica/prevención & control , Hemorragia Posparto/prevención & control , Complicaciones Hematológicas del Embarazo/tratamiento farmacológico , Hemorragia Uterina/prevención & control , Enfermedades de von Willebrand/tratamiento farmacológico , Factor de von Willebrand/uso terapéutico , Adulto , Cesárea , Consanguinidad , Desamino Arginina Vasopresina/uso terapéutico , Femenino , Humanos , Recién Nacido , Placenta Previa/cirugía , Agregación Plaquetaria , Embarazo , Complicaciones Hematológicas del Embarazo/genética , Enfermedades de von Willebrand/complicaciones , Factor de von Willebrand/administración & dosificaciónRESUMEN
A rapid and sensitive method was developed for the simultaneous determination of fluoxetine and its primary metabolite, norfluoxetine, in plasma. It was based on a column-switching approach with a precolumn packed with large size particles coupled with a liquid chromatography-electrospray ionisation-mass spectrometry (LC-ESI-MS). After a simple centrifugation, plasma samples were directly injected onto the precolumn. The endogenous material was excluded thanks to a high flow rate while analytes were retained by hydrophobic interactions. Afterwards, the target compounds were eluted in back flush mode to an octadecyl analytical column and detected by ESI-MS. The overall analysis time per sample, from plasma sample preparation to data acquisition, was achieved in less than 4 min. Method performances were evaluated. The method showed good linearity in the range of 25-1000 ng mL(-1) with a determination coefficient higher than 0.99. Limits of quantification were estimated at 25 ng mL(-1) for fluoxetine and norfluoxetine. Moreover, method precision was better than 6% in the studied concentration range. These results demonstrated that the method could be used to quantify target compounds. Finally, the developed assay proved to be suitable for the simultaneous analysis of fluoxetine and its metabolite in real plasma samples.
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Antidepresivos de Segunda Generación/sangre , Cromatografía Líquida de Alta Presión/métodos , Fluoxetina/análogos & derivados , Fluoxetina/sangre , Espectrometría de Masa por Ionización de Electrospray/métodos , Administración Oral , Antidepresivos de Segunda Generación/administración & dosificación , Antidepresivos de Segunda Generación/metabolismo , Fluoxetina/administración & dosificación , Fluoxetina/metabolismo , Humanos , Factores de TiempoRESUMEN
Analytical procedures, including capillary isoelectric focusing (CIEF), high-performance anion-exchange chromatography coupled to amperometric detection (HPAEC-PAD) and normal-phase chromatography with fluorescence detection are presented for the characterization of a highly O-glycosylated caseinomacropeptide (CGMP) and the detection of subtle glycosylation differences between CGMP Batches obtained with two different preparation procedures. Modified two-step CIEF allowed monitoring of glycopeptide heterogeneity and determination of the isoelectric points of acidic glycoforms. The mixture of wide and narrow pH range ampholytes was optimized to improve glycoform resolution. The pI of the different CGMP glycoforms was evaluated with pI internal standards and found to range between 3.08 and 3.58, which indicates a very acidic glycopeptide. Moreover, the monosaccharide composition was determined with HPAEC-PAD after neutral and amino sugars release by using adequate acidic hydrolysis of CGMP. Results indicated a similar composition for Batches I and II, but the monosaccharide percentages were 3-4 fold higher in Batch I, particularly for galactose and glucose. This likely reflects a higher content in lactose in the case of Batch I. Finally, O-linked oligosaccharides were released with an automated hydrazinolysis and derivatized with a sensitive labelling reagent, 2-aminobenzamide. The derivatives were then analyzed by normal-phase HPLC coupled with fluorescence detection, and separated on the basis of hydrophilic interaction, which allowed oligosaccharide mapping of the two CGMP. It appeared that the two CGMP preparations had an almost identical O-glycan population, but CGMP Batch I was more glycosylated than Batch II. Additionally, the sizes of the separated glycans, expressed as the number of glucose units, were tentatively assigned using calibration with a partial hydrolysate of dextran. In conclusion, a combination of electrophoretic and chromatographic techniques was found powerful in studying glycoprotein heterogeneity and assessing batch-to-batch consistency.
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Caseínas/química , Suplementos Dietéticos/análisis , Polisacáridos/química , Animales , Carbohidratos/análisis , Bovinos , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Glicosilación , Resinas de Intercambio IónicoRESUMEN
The on-line combination of partial-filling capillary electrophoresis and electrospray ionization mass spectrometry was demonstrated for the enantioseparation of pharmaceutical drugs and metabolites, namely amphetamines, methadone, venlafaxine and selected tropane alkaloids. The partial-filling technique proved to be a suitable and efficient approach to avoid mass spectrometry (MS) source contamination, as well as signal suppression due to nonvolatile additives. To achieve chiral separation, various chiral selectors were applied, including neutral and particularly negatively charged cyclodextrins. Because of the countercurrent contribution, charged cyclodextrins were found more suitable for the on-line MS detection of separated enantiomers. Hyphenation of capillary electrophoresis (CE) with mass spectrometry was found appropriate for the stereoselective analysis of methadone in real serum samples. Moreover, the use of MS in the selected ion monitoring mode resulted in a very high selectivity, as well as improved sensitivity compared to UV detection. Finally, with atropine as a model compound, the quantitative performances of the method were evaluated and showed high sensitivity, as well as good repeatability in terms of migration time and peak area ratio.
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Electroforesis Capilar/métodos , Preparaciones Farmacéuticas/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray/métodos , Anfetaminas/aislamiento & purificación , Ciclodextrinas/química , Ciclohexanoles/aislamiento & purificación , Indicadores y Reactivos , Metadona/aislamiento & purificación , Preparaciones Farmacéuticas/análisis , Sensibilidad y Especificidad , Tropanos/aislamiento & purificación , Clorhidrato de VenlafaxinaRESUMEN
An experimental design approach is described to evaluate the main electrophoretic parameters involved in the enantioseparation of pharmaceuticals by capillary electrophoresis (CE) coupled to electrospray ionization-mass spectrometry (ESI-MS). For all experiments, the partial-filling technique was applied to avoid the chiral selector entering in the mass spectrometer ion source with a negative effect on the electrospray performance. To carry out enantioseparation, a volatile buffer constituted of 20 mM ammonium acetate at pH 4.0, and a polyvinyl alcohol-coated capillary were used. Methadone was employed as the model compound and three different cyclodextrins (CDs), namely sulfobutyl ether-beta-CD, carboxymethylated-beta-CD and hydroxypropyl-beta-CD, were selected in order to study the countercurrent process. Two different experimental designs were chosen: (i) a full-factorial design to examine the effects and significance of the investigated factors, and (ii) a central composite face-centered design to establish the mathematical model of the selected responses in function of experimental factors. The chiral selector concentration, percentage of the capillary filled with the chiral selector, and drying gas nebulization pressure were three relevant factors taken into consideration. For each CD, the methadone enantiomeric resolution, apparent selectivity, and migration time of the second enantiomer were established as responses. The latter were systematically related to experimental parameters with the help of multiple linear regression. It is noteworthy that the behaviour was different in function of the chiral selector charge. Results revealed that the nebulization pressure involved in the electrospray process and the CD concentration had a significant effect on the enantiomeric resolution, while the effect of the separation zone length was less pronounced. Finally, response surfaces were drawn from the mathematical model and experimental conditions were selected to allow a robust determination of methadone enantiomers by CE-MS.
Asunto(s)
Electroforesis Capilar/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , beta-Ciclodextrinas , Tampones (Química) , Ciclodextrinas , Concentración de Iones de Hidrógeno , Indicadores y Reactivos , Matemática , Metadona/aislamiento & purificación , Modelos Químicos , Análisis de Regresión , EstereoisomerismoRESUMEN
The distribution of eight calystegines (A(3), A(5), B(1), B(2), B(3), B(4), C(1) and N(1)) and their content was investigated by gas chromatography coupled to mass spectrometry (GC-MS) in Datura metel, Atropa belladonna, Hyoscyamus albus, Mandragora autumnalis, Solanum sodomaeum, Withania somnifera, Withania frutescens and Brunfelsia nitida. The most frequently encountered calystegines were A(3), B(1), B(2) and B(3), while distribution of N(1) and C(1) was more limited. In all the investigated samples, calystegines A(5) and B(4) were never detected. This report focuses for the first time on calystegines in Withania and Brunfelsia genera and in Mandragora autumnalis and Solanum sodomaeum species.
Asunto(s)
Alcaloides/análisis , Solanaceae/química , Calibración , Cromatografía de Gases y Espectrometría de Masas , Especificidad de la Especie , TropanosRESUMEN
Nonaqueous capillary electrophoresis coupled to UV detection is described for the separation and determination of steroidal alkaloids. After optimization of electrophoretic parameters, including the electrolyte nature and the organic solvent composition, a reliable separation of solasodine and solanidine was achieved in a methanol-acetonitrile (20:80, v/v) mixture containing 25 mM ammonium acetate and 1 M acetic acid. For quantitative purposes, a fused-silica capillary with a bubble cell was used and detection was performed at low wavelength (195 nm). Method performances, including migration time and peak area reproducibility, linearity, sensitivity and accuracy, were also evaluated. The method was applied to determine solasodine in Solanum elaeagnifolium berries and Solanum sodomaeum leaves and seeds. To further improve sensitivity in the analysis of solasodine-related compounds, solanidine, demissidine and tomatidine, the developed method was interfaced with electrospray ionization mass spectrometry. In the case of solasodine, the detection limit was estimated at 3 microg/ml for NACE-UV and at 0.05 microg/ml for NACE-MS, in the selected ion-monitoring mode.