Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
SLAS Technol ; 29(4): 100163, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39047813

RESUMEN

Over the last 5 years, IR-MALDESI-MS (Infrared Matrix-Assisted Laser Desorption Electrospray Ionization Mass Spectrometry) has been demonstrated for use in a range of high-throughput biochemical and cellular assays with remarkable sample acquisition rates up to 22 Hz for a single 384-well assay plate. With such high single plate acquisition rates, the rate limiting step becomes how fast subsequent plates can be presented to the MS for analysis. To make this transfer as fast as possible while maintaining safe operation in a laboratory environment, we developed a collaborative robotic plate transfer system (CRPTS) that combines a 6-axis robot with dual plate grippers, a 7th axis conveyor stage, and a 420-plate capacity sample loading window. As a demonstration of the throughput and flexibility of CRPTS, we performed a biochemical assay that monitored the oxidation of tris(2-carboxyethyl)phosphine (TCEP) to screen for nuisance compounds. Using continuous and step motion scan profiles, we analyzed 158,799 compounds contained in 448 assay plates over the course of 12.5 h (Z-Factor=0.87) and 17.5 h (Z-factor=0.99), respectively. Extrapolating these results enables the screening of a million compounds within 6-7 working days.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento , Robótica , Robótica/instrumentación , Robótica/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Ensayos Analíticos de Alto Rendimiento/instrumentación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
2.
J Am Geriatr Soc ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39051828

RESUMEN

BACKGROUND: Clinicians and patients often face a decision to continue or discontinue statins. We examined the impact of discontinuation of statins compared with continuation on clinical outcomes (all-cause mortality, cardiovascular [CV] mortality, CV events, and quality of life). METHODS: We conducted a systematic review. Randomized controlled trials (RCTs), cohort studies, case-control studies, and quasi-randomized studies among people ≥18 years were eligible. We searched MEDLINE, Embase, and Cochrane Central Registry (inception to August 2023). Two independent reviewers performed screening and extracted data. Quality assessment was performed by one author and verified by another. We summarized results narratively, performed meta-analysis for a subset of studies, and used GRADE to assess certainty of evidence. We summarized findings in the subgroup of persons ≥75 years. RESULTS: We retrieved 8369 titles/abstracts; 37 reports from 36 studies were eligible. This comprised 35 non-randomized studies (n = 1,708,684) and 1 RCT (n = 381). The 1 RCT was conducted among persons with life expectancy <1 year and showed there is probably no difference in 60-day mortality (risk difference = 3.5%, 90% CI -3.5 to 10.5) for statin discontinuation compared with continuation. Non-randomized studies varied in terms of population and setting, but consistently suggested that statin discontinuation might be associated with a relative increased risk of mortality (hazard ratio (HR) 1.92, 95% CI 1.52 to 2.44, nine studies), CV mortality (HR 1.63, 95% CI 1.27 to 2.10, five reports), and CV events (HR 1.31, 95% CI 1.23 to 1.39, eight reports). Findings in people ≥75 years were consistent with main results. There was a high degree of uncertainty in findings from non-randomized studies due to methodological limitations. CONCLUSIONS: Statin discontinuation does not appear to affect short-term mortality near end-of-life based on one RCT. Outside of this population, findings from non-randomized studies consistently suggested statin discontinuation may be associated with worse outcomes, though this is uncertain.

3.
JAMA ; 331(14): 1215-1224, 2024 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-38592385

RESUMEN

Importance: The accuracy of screening tests for alcohol use disorder (defined as a problematic pattern of alcohol use leading to clinically significant impairment or distress) requires reassessment to align with the latest definition in the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) (DSM-5). Objective: To assess the diagnostic accuracy of screening tools in identifying individuals with alcohol use disorder as defined in the DSM-5. Data Sources and Study Selection: The databases of MEDLINE and Embase were searched (January 2013-February 2023) for original studies on the diagnostic accuracy of brief screening tools to identify alcohol use disorder according to the DSM-5 definition. Because diagnosis of alcohol use disorder does not include excessive alcohol use as a criterion, studies of screening tools that identify excessive or high-risk drinking among younger (aged 9-18 years), older (aged ≥65 years), and pregnant persons also were retained. Data Extraction and Synthesis: Sensitivity, specificity, and likelihood ratios (LRs) were calculated. When appropriate, a meta-analysis was performed to calculate a summary LR. Results: Of 4303 identified studies, 35 were retained (N = 79 633). There were 11 691 individuals with alcohol use disorder or a history of excessive drinking. Across all age categories, a score of 8 or greater on the Alcohol Use Disorders Identification Test (AUDIT) increased the likelihood of alcohol use disorder (LR, 6.5 [95% CI, 3.9-11]). A positive screening result using AUDIT identified alcohol use disorder better among females (LR, 6.9 [95% CI, 3.9-12]) than among males (LR, 3.8 [95% CI, 2.6-5.5]) (P = .003). An AUDIT score of less than 8 reduced the likelihood of alcohol use disorder similarly for both males and females (LR, 0.33 [95% CI, 0.20-0.52]). The abbreviated AUDIT-Consumption (AUDIT-C) has sex-specific cutoff scores of 4 or greater for males and 3 or greater for females, but was less useful for identifying alcohol use disorder (males: LR, 1.8 [95% CI, 1.5-2.2]; females: LR, 2.0 [95% CI, 1.8-2.3]). The AUDIT-C appeared useful for identifying measures of excessive alcohol use in younger people (aged 9-18 years) and in those older than 60 years of age. For those younger than 18 years of age, the National Institute on Alcohol Abuse and Alcoholism age-specific drinking thresholds were helpful for assessing the likelihood of alcohol use disorder at the lowest risk threshold (LR, 0.15 [95% CI, 0.11-0.21]), at the moderate risk threshold (LR, 3.4 [95% CI, 2.8-4.1]), and at the highest risk threshold (LR, 15 [95% CI, 12-19]). Among persons who were pregnant and screened within 48 hours after delivery, an AUDIT score of 4 or greater identified those more likely to have alcohol use disorder (LR, 6.4 [95% CI, 5.1-8.0]), whereas scores of less than 2 for the Tolerance, Worried, Eye-Opener, Amnesia and Cut-Down screening tool and the Tolerance, Annoyed, Cut-Down and Eye-Opener screening tool identified alcohol use disorder similarly (LR, 0.05 [95% CI, 0.01-0.20]). Conclusions and Relevance: The AUDIT screening tool is useful to identify alcohol use disorder in adults and in individuals within 48 hours postpartum. The National Institute on Alcohol Abuse and Alcoholism youth screening tool is helpful to identify children and adolescents with alcohol use disorder. The AUDIT-C appears useful for identifying various measures of excessive alcohol use in young people and in older adults.


Asunto(s)
Alcoholismo , Tamizaje Masivo , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Embarazo , Adulto Joven , Alcoholismo/diagnóstico , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Tamizaje Masivo/métodos
4.
Can Geriatr J ; 26(4): 517-523, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38045883

RESUMEN

Background: Three landmark trials on the use of acetylsalicylic acid (ASA) for primary prevention of cardiovascular disease (CVD) were published in 2018. Since then, major clinical practice guidelines have been updated with recommendations against the routine use of ASA for primary CVD prevention, particularly in older adults. However, little is known about the uptake of this evidence into real world practice. The purpose of this study was to assess the change in ASA usage for primary prevention of CVD in older adults between 2017 and 2021. Methods: A retrospective cross-sectional study of ASA use for primary prevention in ambulatory older adults without known CVD in an urban Canadian city was conducted. Results: Seven hundred and fifty-six participants were included. The mean age was 78.9 years (standard deviation 7.9) and 64.8% were female. One hundred and thirty (17.2%) participants used ASA for primary prevention, including 20.3% in 2017, 17.0% in 2018, 21.8% in 2019, 16.3% in 2020, and 11.0% in 2021 (p = .061). Female sex was associated with lower ASA use (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.29-0.68) and hypertension was associated with higher ASA use (OR 2.72, 95% CI 1.73-4.29). Conclusions: Use of ASA for primary CVD prevention in older Canadians decreased between 2017 and 2021, suggesting an uptake of clinical trial data and practice guideline recommendations. Focusing on deprescribing of ASA for primary CVD prevention continues to be warranted, given the risks associated with ASA in this population.

5.
Eur Geriatr Med ; 14(4): 747-760, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37393587

RESUMEN

PURPOSE: Advancing age, declining health status, and a shift in benefit/risk balance warrant judicious use of preventive medications in older persons, including consideration of deprescribing. Lack of guidance on deprescribing is a major barrier for prescribers to consider deprescribing in daily practice. The aim of this review was to evaluate to what extent osteoporosis guidelines include bisphosphonate deprescribing recommendations. METHODOLOGY: We conducted a systematic review, searching PubMed, Embase, and grey literature. We included guidelines on treatment of osteoporosis with bisphosphonates. Two independent reviewers screened titles, abstracts, and full texts. Recommendations for deprescribing were extracted, and quality of guidelines were assessed. RESULTS: Among 9345 references, 42 guidelines were included. A total of 32 (76%) guidelines included deprescribing recommendations: 29 (69%) guidelines included non-specific deprescribing recommendations framed as a drug holiday, of which 2 (5%) also included specific deprescribing recommendations based on individual health context (e.g. life expectancy, frailty, function, preferences/goals). Twenty-four (57%) guidelines included practical deprescribing recommendations, and 27 (64%) guidelines included recommendations for when deprescribing should not be considered. CONCLUSION: Bisphosphonate deprescribing recommendations in osteoporosis guidelines were primarily framed as drug holidays, with limited guidance on how to make individualized deprescribing decisions based on individual health context. This suggests a need for additional focus on deprescribing in osteoporosis guidelines.


Asunto(s)
Deprescripciones , Osteoporosis , Humanos , Anciano , Anciano de 80 o más Años , Difosfonatos/uso terapéutico , Osteoporosis/tratamiento farmacológico , Estado de Salud , Esperanza de Vida
7.
Int J Pharm ; 636: 122842, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36925024

RESUMEN

Intravenous (IV) administration of poorly water-soluble small molecule therapeutics can lead to precipitation during mixing with blood. This can limit characterization of pharmacological and safety endpoints in preclinical models. Most often, tests of kinetic and thermodynamic solubility are used to optimize the formulation for solubility prior to infusion in animals, but these do not capture the dynamic precipitation processes that take place during in-vivo administration. To better capture the fluid dynamic processes that occur during IV administration, we developed the Optical Spatial PREcipitation analYzer (OSPREY) as a method to quantify the amount and size of compound precipitates in whole blood using a flow-through system that mimics IV administration. Here, we describe the OSPREY device and its underlying imaging processing methods. We then validate the ability to accurately segment particles according to their size using monodisperse suspensions of microspheres (diameter 50 to 425 µm). Next, we use a tool compound, ABT-737, to study the effects of compound concentration, vessel flow rate, compound infusion rate and vessel diameter on precipitation. Finally, we use the physiological diameter and flow rate of rat femoral vein and dog saphenous vein to demonstrate the potential of OSPREY to model in-vivo precipitation in a controlled, dynamic in-vitro assay.


Asunto(s)
Agua , Ratas , Animales , Perros , Inyecciones , Solubilidad , Precipitación Química
8.
Anal Chem ; 94(12): 4913-4918, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-35290016

RESUMEN

Infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) mass spectrometry is an ambient-direct sampling method that is being developed for high-throughput, label-free, biochemical screening of large-scale compound libraries. Here, we report the development of an ultra-high-throughput continuous motion IR-MALDESI sampling approach capable of acquiring data at rates up to 22.7 samples per second in a 384-well microtiter plate. At top speed, less than 1% analyte carryover is observed from well-to-well, and signal intensity relative standard deviations (RSD) of 11.5% and 20.9% for 3 µM 1-hydroxymidazolam and 12 µM dextrorphan, respectively, are achieved. The ability to perform parallel kinetics studies on 384 samples with a ∼30 s time resolution using an isocitrate dehydrogenase 1 (IDH1) enzyme assay is shown. Finally, we demonstrate the repeatability and throughput of our approach by measuring 115200 samples from 300 microtiter plate reads consecutively over 5.54 h with RSDs under 8.14% for each freshly introduced plate. Taken together, these results demonstrate the use of IR-MALDESI at sample acquisition rates that surpass other currently reported direct sampling mass spectrometry approaches used for high-throughput compound screening.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento , Espectrometría de Masa por Ionización de Electrospray , Pruebas de Enzimas , Rayos Láser , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
9.
SLAS Technol ; 26(1): 113-116, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32508230

RESUMEN

Centralized high-throughput purification laboratories routinely produce large numbers of test tubes with fractions containing the purified compounds of interest interspersed with test tubes containing fractions collected from undesired peaks. Because the next step after purification entails the removal of the solvent in a centrifugal evaporator with multiple sample positions per rotor, select test tubes must be labeled prior to dry-down to track the identity of each compound. The diversity of test tube sizes and tray configurations from different chromatography system vendors complicates this labeling task. Therefore, the development of an automated tube labeler that can accommodate a multitude of test tube and tray sizes can reduce the chances of error as well as reduce the hands-on labor required to complete this tedious but essential task. Custom hardware and software have been implemented to inform and to enable the Pick-n-Place arm of a commercially available Tecan EVO robotic system to pick up and present select tubes, filled with purified chromatography fractions from a multitude of vendor trays, to a custom label application station integrated with a commercially available Zebra label printer. Particular challenges existed with accurately positioning tubes in Agilent G1364-84544 trays onto the deck of the instrument. The resulting instrument reduces hands-on time for labeling fractions by approximately 60%.


Asunto(s)
Cromatografía , Laboratorios , Automatización , Programas Informáticos
10.
Artículo en Inglés | MEDLINE | ID: mdl-33092990

RESUMEN

INTRODUCTION: Academic medical centers (AMCs) and community physicians seeking to establish a clinically integrated network (CIN) may benefit from a road map to navigate the opportunities and challenges of such an organizational structure. Creating and participating in a CIN requires careful consideration, investment of time, financial resources, alignment of a new quality infrastructure, shared governance, and vision. POTENTIAL BENEFITS, CHALLENGES, AND REGULATORY CONSIDERATIONS: Potential AMC benefits include geographic clinical expansion, the ability to provide care for a broader population of patients, a mechanism to collaborate with regional physician graduates, and an expansion of available teaching sites for trainees. Potential benefits to community practices include propagation of high-value care, enhanced access to evidence-based protocols and priority measures, preparation for value-based reimbursement structures, and connection to an institution that produces future health care practitioners. Challenges to CIN creation include goal alignment, trust between AMC and community partners, acceptance of common quality measures and benchmarks, access to shared data, and local adoption of quality improvement activities. QUALITY AND INFORMATION TECHNOLOGY CONSIDERATIONS: At inception the mission was to create an innovative academic-community alliance delivering high-quality, high-value, personalized care. Defining the clinical quality goals, measurement, governance, and improvement strategy, as well as information technology structure and decision making, are described. FUTURE DIRECTIONS: The network continues to grow and now includes more than 350 physicians, in 16 different specialties across 50 different independent medical practices throughout Southern California. We believe this builds a firm foundation for value-based health care.

11.
ACS Med Chem Lett ; 10(5): 703-707, 2019 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-31097986

RESUMEN

Automation of chemistry at a pharmaceutical company commonly entails bringing commercial solutions in-house, reproducing manual processes with a robot, or integrating multiple instruments to eliminate human intervention. A strategy of industrializing proven approaches, while financially justifiable, however, does not encourage innovation. On the other hand, trying to automate unproven or difficult processes may seem to be risky but can actually accelerate the adoption, modification, or rejection of novel technologies. Having chemists and engineers work together to develop automation that accelerates the development and evaluation of innovative concepts is one blueprint for delivering a competitive advantage to an organization.

12.
Org Biomol Chem ; 14(27): 6591-5, 2016 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-27314279

RESUMEN

The efficient synthesis of cyclopropyl boronic esters in library format using a diazomethane flow reactor has been achieved. A pivotal component of the system is a fully automated tube-in-tube reactor allowing for safe handling of hazardous diazomethane on repeated small scale and for the generation of larger quantities of product. The setup enables the repeated execution of Pd-catalyzed cyclopropanation reactions without compromising its operation over time.

13.
BMC Immunol ; 15: 46, 2014 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-25311344

RESUMEN

BACKGROUND: Innate immunity and tissue proliferation play important roles in otitis media (OM), the most common disease of childhood. CJUN terminal kinase (JNK) is potentially involved in both processes. RESULTS: Genes involved in both innate immune and growth factor activation of JNK are upregulated during OM, while expression of both positive and negative JNK regulatory genes is altered. When compared to wildtypes (WTs), C57BL/6 mice deficient in JNK1 exhibit enhanced mucosal thickening, with delayed recovery, enhanced neutrophil recruitment early in OM, and delayed bacterial clearance. In contrast, JNK2-/- mice exhibit delayed mucosal hyperplasia that eventually exceeds that of WTs and is slow to recover, delayed recruitment of neutrophils, and failure of bacterial clearance. CONCLUSIONS: The results suggest that JNK1 and JNK2 play primarily opposing roles in mucosal hyperplasia and neutrophil recruitment early in OM. However, both isoforms are required for the normal resolution of middle ear infection.


Asunto(s)
Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Otitis Media/enzimología , Animales , Oído Medio/enzimología , Oído Medio/microbiología , Oído Medio/patología , Regulación Enzimológica de la Expresión Génica , Haemophilus influenzae/fisiología , Hiperplasia , Isoenzimas/genética , Isoenzimas/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Leucocitos/patología , Sistema de Señalización de MAP Quinasas/genética , Ratones Endogámicos C57BL , Membrana Mucosa/patología , Otitis Media/microbiología , Otitis Media/patología
14.
J Lab Autom ; 19(2): 176-82, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24352687

RESUMEN

A flexible and integrated flow-chemistry-synthesis-purification compound-generation and sample-management platform has been developed to accelerate the production of small-molecule organic-compound drug candidates in pharmaceutical research. Central to the integrated system is a Mitsubishi robot, which hands off samples throughout the process to the next station, including synthesis and purification, sample dispensing for purity and quantification analysis, dry-down, and aliquot generation.


Asunto(s)
Técnicas Químicas Combinatorias/métodos , Descubrimiento de Drogas/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Compuestos Orgánicos/aislamiento & purificación , Compuestos Orgánicos/farmacología , Manejo de Especímenes/métodos , Compuestos Orgánicos/síntesis química
15.
IEEE Trans Pattern Anal Mach Intell ; 34(3): 587-600, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21844623

RESUMEN

Recent years have witnessed the growing popularity of sensor and sensor-network technologies, supporting important practical applications. One of the fundamental issues is how to accurately locate a user with few labeled data in a wireless sensor network, where a major difficulty arises from the need to label large quantities of user location data, which in turn requires knowledge about the locations of signal transmitters or access points. To solve this problem, we have developed a novel machine learning-based approach that combines collaborative filtering with graph-based semi-supervised learning to learn both mobile users' locations and the locations of access points. Our framework exploits both labeled and unlabeled data from mobile devices and access points. In our two-phase solution, we first build a manifold-based model from a batch of labeled and unlabeled data in an offline training phase and then use a weighted k-nearest-neighbor method to localize a mobile client in an online localization phase. We extend the two-phase colocalization to an online and incremental model that can deal with labeled and unlabeled data that come sequentially and adapt to environmental changes. Finally, we embed an action model to the framework such that additional kinds of sensor signals can be utilized to further boost the performance of mobile tracking. Compared to other state-of-the-art systems, our framework has been shown to be more accurate while requiring less calibration effort in our experiments performed on three different testbeds.

16.
J Chromatogr A ; 1216(34): 6162-9, 2009 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-19589529

RESUMEN

Experiments were performed to demonstrate the potential of counter-current chromatography (CCC) for the isolation of drugs and their metabolites from biological matrices relevant to the metabolism studies of pharmaceutical research. Examples of typical drugs are spiked into biological media ex vivo to provide test samples for analysis. A mass spectrometer hyphenated to a CCC allows for the detection of small molecule drugs within the matrix through selected ion monitoring, and fraction collection can provide material for further structural elucidation by NMR.


Asunto(s)
Líquidos Corporales/química , Distribución en Contracorriente/métodos , Preparaciones Farmacéuticas/aislamiento & purificación , Métodos Analíticos de la Preparación de la Muestra , Animales , Bilis/química , Análisis Químico de la Sangre , Distribución en Contracorriente/instrumentación , Perros , Humanos , Espectrometría de Masas , Preparaciones Farmacéuticas/sangre , Solventes
17.
J Chromatogr A ; 1216(19): 4154-60, 2009 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-19108843

RESUMEN

Experiments were performed to evaluate whether counter-current chromatography (CCC) could function as an alternative purification method to reversed-phase high-performance liquid chromatography (RP-HPLC) and normal-phase supercritical fluid chromatography (SFC). RP-HPLC and SFC are the routine methods currently used in our high-throughput purification (HTP) facility for the purification of high-throughput organic synthesis (HTOS) libraries and medicinal chemistry reaction mixtures. Pre-equilibration of the solvent mixture layers was not mandatory for effective chromatography when hexanes-ethyl acetate-methanol-water (HEMW) solvent mixtures were used. Key to the use of CCC for high-throughput applications is the ability to effectively select a solvent system appropriate to each library member. Pilot-scale CCC elution time was used to estimate a starting solvent ratio and RP-HPLC retention time was then used to adjust solvent ratios within a particular library. It was also found that dimethyl sulfoxide (DMSO) and DMSO-methanol were suitable as sample injection solvents when using the HEMW solvent systems.


Asunto(s)
Distribución en Contracorriente/métodos , Compuestos Orgánicos/química , Bibliotecas de Moléculas Pequeñas , Acilación , Cromatografía Líquida de Alta Presión , Dimetilsulfóxido/química , Diseño de Equipo , Ibuprofeno/aislamiento & purificación , Cetoprofeno/aislamiento & purificación , Metanol/química , Solubilidad , Solventes/química
18.
J Comb Chem ; 10(1): 88-93, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18095655

RESUMEN

This manuscript details the construction of a fully automated flow hydrogenation apparatus for use in high-throughput organic synthesis. The instrument comprises of a Bohdan robot platform coupled with a ThalesNano H-cube hydrogenator and a series of solvent valves and pumping mechanisms. Using this instrument, we have been able to fully automate a number of key transformations that could not otherwise be conveniently undertaken in a high-throughput manner.


Asunto(s)
Química Orgánica/instrumentación , Técnicas Químicas Combinatorias/instrumentación , Diseño de Fármacos , Robótica , Catálisis , Química Orgánica/métodos , Técnicas Químicas Combinatorias/métodos , Diseño de Equipo , Hidrogenación , Reproducibilidad de los Resultados , Bibliotecas de Moléculas Pequeñas/química
19.
Assay Drug Dev Technol ; 2(1): 63-9, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15090211

RESUMEN

The modulation of fatty acid metabolism and especially the stimulation of fatty acid oxidation in liver or skeletal muscle are attractive therapeutic approaches for the treatment of obesity and the associated insulin resistance. However, current beta-oxidation assays are run in very low throughput, which represents an obstacle for drug discovery in this area. Here we describe results for a 48-well beta-oxidation assay using a new instrument design. A connecting chamber links two adjacent wells to form an experimental unit, in which one well contains the beta-oxidation reaction and the other captures CO(2). The experimental units are sealed from each other and from the outside to prevent release of radioactivity from the labeled substrate. CO(2) capture in this instrument is linear with time and over the relevant experimental range of substrate concentration. Cellular viability is maintained in the sealed environment, and cells show the expected responses to modulators of beta-oxidation, such as the AMP kinase activator 5-aminoimidazole carboxamide riboside. Data are presented for different lipid substrates and cell lines. The increased throughput of this procedure compared with previously described methods should facilitate the evaluation of compounds that modulate fatty acid metabolism.


Asunto(s)
Bioensayo/instrumentación , Ácidos Grasos/metabolismo , Animales , Caprilatos/metabolismo , Dióxido de Carbono/metabolismo , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Separación Celular , Supervivencia Celular/efectos de los fármacos , Glucosa/metabolismo , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Técnicas In Vitro , Neoplasias Hepáticas/metabolismo , Oxidación-Reducción , Palmitatos/metabolismo , Ratas , Ratas Sprague-Dawley
20.
Recept Channels ; 9(1): 19-28, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12825295

RESUMEN

The drug discovery process centers around finding and optimizing novel compounds active at therapeutic targets. This process involves direct and indirect measures of how compounds affect the behavior of the target in question. The sheer number of compounds that must be tested poses problems for classes of ion channel targets for which direct functional measurements (e.g., traditional patch-clamping) are too cumbersome and indirect measurements (e.g., Ca(2+)-sensitive dyes) lack sufficient sensitivity or require unacceptable compromises. We present an optimized process for obtaining large numbers of direct electrophysiological measurements (two-electrode voltage-clamp) from Xenopus oocytes using a combination of automated oocyte handling, efficient and flexible liquid delivery, parallel operation, and powerful integrated data analysis. These improvements have had a marked impact, increasing the contribution electrophysiology makes in optimizing lead compound series and the discovery of new ones. The design of the system is detailed along with examples of data generated in support of lead optimization and discovery.


Asunto(s)
Bioquímica/métodos , Electrofisiología/instrumentación , Electrofisiología/métodos , Animales , Automatización , Electrodos , Canales Iónicos/metabolismo , Canales Iónicos/fisiología , Oocitos/metabolismo , Xenopus laevis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA