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1.
MedEdPORTAL ; 19: 11328, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560407

RESUMO

Introduction: Opioid pain management is complex and requires a collaborative approach. To prepare health professions students to care for patients who have chronic pain, we developed an interprofessional education (IPE) session for delivery using a virtual platform that featured a standardized patient (SP) interaction. Methods: The SP case highlighted a patient on opioids for chronic low back pain resulting from a car accident. Despite no improvement in pain or function, the patient continued taking opioids and developed behaviors that could represent opioid misuse. During the synchronous, online session, interprofessional teams of students interviewed an SP and collaborated to develop a holistic care plan to address the patient's pain and potential opioid misuse. The session evaluation included pre- and postsession surveys. Results: Over 750 students from medicine, pharmacy, nursing, and social work programs participated in the virtual IPE sessions during a single year. Students rated the session positively. Matched survey responses suggested improved confidence in knowledge and skills, and learning through Zoom was rated favorably. Discussion: We successfully implemented a synchronous online IPE session involving SP interactions that allowed students to practice team-based care of a patient with chronic pain who was taking opioids. Based on the success of this IPE session, including the success of the online delivery model, future IPE sessions will continue virtually.


Assuntos
Dor Crônica , Transtornos Relacionados ao Uso de Opioides , Humanos , Analgésicos Opioides/uso terapêutico , Educação Interprofissional , Dor Crônica/tratamento farmacológico , Relações Interprofissionais
2.
Pain Manag Nurs ; 24(5): 558-566, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37455185

RESUMO

BACKGROUND: Substance use disorders (SUDs) are highly prevalent among adults with persistent pain. Yet, standard competencies for integrating pain and SUD content are lacking across health science student curricula. Additionally, pharmacotherapies to treat SUDs are underutilized. AIM: To address these gaps, a team of health science faculty created an interprofessional simulation activity using a standardized patient and evaluated learner outcomes related to assessment and treatment of comorbid persistent pain and substance use. METHODS: A total of 304 health science students representing nursing, medicine, pharmacy, and social work programs attended virtual learning sessions. Interprofessional student teams developed a team-based care plan for an adult with musculoskeletal pain who takes prescribed opioids while using alcohol. Pre- and post-activity surveys assessing knowledge and confidence were matched for 198 students. Descriptive statistics summarized survey data with inferential analysis of paired data. RESULTS: The largest significant improvements between pre- and post-activity knowledge were observed in items specific to pharmacotherapy options for alcohol and opioid use disorders. Similar gains were noted in students' confidence regarding pharmacotherapies. No significant differences were noted on pre-post-activity knowledge scores between the three main profession groups (medicine, nursing, and pharmacy). CONCLUSIONS: Students attending this interprofessional simulation demonstrated improved knowledge and confidence, particularly in pharmacotherapies for alcohol and opioid use disorders. Replication of such programs can be used to provide consistent content across health science disciplines to heighten awareness and receptivity to medications available to treat SUDs in people treated for persistent pain. The curriculum is freely available from the corresponding author.


Assuntos
Educação Interprofissional , Transtornos Relacionados ao Uso de Opioides , Humanos , Adulto , Avaliação de Programas e Projetos de Saúde , Currículo , Dor
3.
Am J Pharm Educ ; 86(9): ajpe8842, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34893468

RESUMO

Objective. The aim of this mixed-methods study was to examine the effect of disabled backward navigation on computerized calculation examinations in multiple courses.Methods. Student performance on comprehensive pharmacy calculation examinations before and after implementation of disabled backward navigation were compared. Deidentified data from ExamSoft were used to determine median examination scores, passing rates, and time to completion for all three attempts given on comprehensive calculation exams held in a pharmacy calculations course (PharDSci 504) and in three applied patient care laboratory courses (Pharm 531, 541, and 551). An anonymous, voluntary student survey gathered student perceptions of disabled backward navigation. Qualitative data were evaluated for thematic findings.Results. The impact of disabled backward navigation on test scores and passing rates varied by course and test attempt. Students in Pharm 541 and 551 performed significantly worse on the initial test attempt after backward navigation was disabled compared to the previous year, with no significant differences in student performance seen on the retakes. Performance in PharDSci 504 and Pharm 531 followed the opposite pattern, with no significant difference in performance for the initial tests but significantly increased performance on the retakes. The amount of time spent on examinations either significantly decreased or remained the same. Student perceptions were generally consistent across all cohorts, with at least 74% agreeing that disabling backward navigation increased examination difficulty.Conclusion. Disabling backward navigation had a mixed effect on student examination performance. This may highlight how student behaviors change as backward navigation is disabled.


Assuntos
Educação em Farmácia , Farmácia , Humanos , Avaliação Educacional/métodos , Educação em Farmácia/métodos , Exame Físico , Estudantes
4.
Pharm Res ; 38(7): 1139-1156, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34254223

RESUMO

PURPOSE: A dataset of fraction excreted unchanged in the urine (fe) values was developed and used to evaluate the ability of preclinical animal species to predict high urinary excretion, and corresponding poor metabolism, in humans. METHODS: A literature review of fe values in rats, dogs, and monkeys was conducted for all Biopharmaceutics Drug Disposition Classification System (BDDCS) Class 3 and 4 drugs (n=352) and a set of Class 1 and 2 drugs (n=80). The final dataset consisted of 202 total fe values for 135 unique drugs. Human and animal data were compared through correlations, two-fold analysis, and binary classifications of high (fe ≥30%) versus low (<30%) urinary excretion in humans. Receiver Operating Characteristic curves were plotted to optimize animal fe thresholds. RESULTS: Significant correlations were found between fe values for each animal species and human fe (p<0.05). Sixty-five percent of all fe values were within two-fold of human fe with animals more likely to underpredict human urinary excretion as opposed to overpredict. Dogs were the most reliable predictors of human fe of the three animal species examined with 72% of fe values within two-fold of human fe and the greatest accuracy in predicting human fe ≥30%. ROC determined thresholds of ≥25% in rats, ≥19% in dogs, and ≥10% in monkeys had improved accuracies in predicting human fe of ≥30%. CONCLUSIONS: Drugs with high urinary excretion in animals are likely to have high urinary excretion in humans. Animal models tend to underpredict the urinary excretion of unchanged drug in humans.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Eliminação Renal/fisiologia , Animais , Conjuntos de Dados como Assunto , Cães , Haplorrinos , Humanos , Curva ROC , Ratos , Especificidade da Espécie
5.
Curr Pharm Teach Learn ; 13(4): 429-437, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33715807

RESUMO

BACKGROUND: An interprofessional education (IPE) activity was designed for health professional students in pharmacy, medicine, nursing, social work, and addiction studies. The goals were to practice team-based collaboration for patients who are prescribed opioids for chronic pain and to evaluate student responses to the activity. INTERPROFESSIONAL EDUCATION ACTIVITY: Student teams were guided through an unfolding patient case that included evaluating the patient's history, screening tool results, morphine equivalent dose, prescription monitoring program report, and videos of a patient-provider interaction. The two-hour, in-person IPE activity culminated in creation of a patient-centered treatment plan. Surveys were administered to compare pre- and post-course opioid knowledge and post-course IPE attitudes among the healthcare professions. DISCUSSION: Pharmacy students' baseline opioid knowledge scores were similar to nursing students, significantly lower than medical students, and significantly higher than social work students. Pharmacy students reported significantly higher gains in opioid knowledge than medical students. Nursing and social work students showed significantly higher levels of agreement that the course enhanced attitudes toward interprofessional collaboration compared to medicine and pharmacy students. Students most frequently noted working with other professions as the most valuable aspect of the IPE activity. IMPLICATIONS: Training gaps can be met using novel IPE activities specific to chronic pain and opioid use. Depending on profession, students demonstrated varied baseline knowledge regarding opioid use for chronic pain. Comparing knowledge gains and attitudes on IPE collaboration among professions can detect areas for program refinement to address each professions' unique needs.


Assuntos
Analgésicos Opioides , Estudantes de Medicina , Analgésicos Opioides/uso terapêutico , Humanos , Educação Interprofissional , Relações Interprofissionais , Dor
6.
Am J Pharm Educ ; 84(9): ajpe7749, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33012791

RESUMO

Objective. To examine the relationship between class attendance by Doctor of Pharmacy students and their performance on pharmacotherapy examinations within an active-learning classroom model. Methods. Second-year pharmacy students enrolled in a pharmacotherapy course series were included in the study (N=160). Class attendance was taken manually by members of the study team over a one-year study period (fall 2017 and spring 2018 semesters). Course attendance was not required and had no direct impact on student grades. Scores from the six competency-based examinations and overall course grades for each semester course, respectively, were then linked to class attendance records. Two additional examination attempts (retake and extended learning experience) were administered to students who did not receive a score of at least 80% on the initial exam or retake exam, respectively. Results. Class attendance was documented during 48 class sessions. Of the six examinations given each semester, students required an average of 1 retake of the examination during the fall semester and 1.5 retakes in the spring semester. A significant negative correlation was found in both courses between students missing more classes and receiving a lower final course grade. For each missed class session, there was a reduction in overall course grade of 0.18% and 0.14% in the fall and spring courses, respectively. Conclusion. Regular class attendance by pharmacy students enrolled in an active-learning pharmacotherapy curriculum was associated with higher scores on examinations. The results of this study illustrate the importance of attending active-learning sessions to attain higher examination scores. Further research is needed to determine whether class attendance is associated with students' improved ability to apply pharmacotherapy concepts.


Assuntos
Absenteísmo , Tratamento Farmacológico , Educação em Farmácia , Avaliação Educacional , Aprendizagem Baseada em Problemas , Estudantes de Farmácia , Currículo , Humanos
7.
Am J Pharm Educ ; 84(7): ajpe7695, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32773828

RESUMO

Objective. To identify the specific study behaviors that promoted student pharmacists' success in an active-learning pharmacy curriculum. Methods. The Washington State University College of Pharmacy and Pharmaceutical Sciences implemented an active-learning, flipped classroom model for instruction to equitably deliver course content to Doctor of Pharmacy students on both its main and extended campuses. Students' ability to adapt to the new model and its impact on their study behaviors were unknown. A qualitative descriptive design that included semi-structured interviews was applied to evaluate the study behaviors of high-performing students. The study sample included 13 third and fourth professional year pharmacy students in the top 20% of their respective classes. Results. Interview responses were unaffected by baseline demographics such as gender and year of graduation. Content analysis generated five primary themes related to the behavioral strategies used by high performers: preparing for class, preparing for testing, seeking help, knowing yourself, and building on strengths. These were mapped to the four tenants of Wenger's social learning theory in the representation of findings: learning as doing, learning as belonging, learning as becoming, and learning as experience. Conclusion. High-performing students demonstrated a refined ability to select and modify study behaviors that aided in their academic success, demonstrating a high degree of metacognition. The results of this research may assist pharmacy faculty members in identifying critical elements for success of students enrolled in pharmacy programs using an active learning model.


Assuntos
Comportamento/fisiologia , Farmacêuticos/psicologia , Estudantes de Farmácia/psicologia , Sucesso Acadêmico , Currículo , Educação em Farmácia/métodos , Avaliação Educacional/métodos , Humanos , Assistência Farmacêutica , Farmácia/métodos , Aprendizagem Baseada em Problemas/métodos , Washington
8.
Curr Pharm Teach Learn ; 12(5): 549-557, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32336452

RESUMO

INTRODUCTION: To better elucidate the impact of cooperative learning outside the classroom, a student-initiated research project was conducted to explore the effects of participating in peer-led study groups (PLSGs) on student examination scores and perceptions. METHODS: First-year pharmacy students were given the opportunity to participate in weekly PLSGs for a pharmacogenomics course during spring 2016 and spring 2017. Student exam performance was stratified by those who attended vs. those who did not. Optional pre- and post-course surveys examined student perceptions of PLSGs. RESULTS: No significant differences were seen between the attendance groups in spring 2016. In spring 2017, student attendees were significantly more likely to pass two of their six exams (p = .04, p = .0029) and to have higher exam scores on one exam (p = .02) in comparison to non-attendees. Overall exam score averages were significantly different between attendees and non-attendees during spring 2017 (p = .03) but not during spring 2016 (p = .38). Perception surveys indicated students believed participation helped them to demonstrate competency and build confidence. Additionally, students reported they felt more comfortable clarifying questions during the study groups vs. during class time. CONCLUSIONS: The impact of study group participation on student exam performance was minimal over the two years of data collection, but there were instances where exam scores were positively impacted. Students perceived value in study group participation even if it did not translate directly to improved exam performance on all exams.


Assuntos
Grupo Associado , Estudantes de Farmácia/estatística & dados numéricos , Habilidades para Realização de Testes/métodos , Avaliação Educacional/métodos , Avaliação Educacional/estatística & dados numéricos , Humanos , Percepção , Estudantes de Farmácia/psicologia , Inquéritos e Questionários , Habilidades para Realização de Testes/normas , Habilidades para Realização de Testes/estatística & dados numéricos
9.
Am J Pharm Educ ; 81(1): 11, 2017 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-28289301

RESUMO

Objective. To design and implement a pharmacogenomics course that focuses on analysis and integration of pharmacogenomic data into clinical practice and to explore how participation in the course influences student self-confidence. Design. The Basic and Clinical Pharmacogenomics course content was divided into three modules: genetic-based didactic sessions, genomic techniques and self-genotype/phenotype laboratory exercise, and clinical-based case studies. Student learning assessment included knowledge- and application-based tests and performance on a group project. Assessment. Effectiveness of the course was evaluated using results of student performance on coded test questions, student perceptions on pre- and post-course self-assessments, performance on a group project, and course evaluation results. Student pharmacists successfully demonstrated competency in pharmacogenomics knowledge-based learning, demonstrated their abilities to apply learned skills in clinical-based scenarios, and reported improved confidence in analyzing patient-based genomic testing results. Conclusions. This course appears to have contributed to student learning and positively influenced student self-confidence in pharmacogenomics.


Assuntos
Currículo , Educação em Farmácia/organização & administração , Farmacogenética/educação , Competência Clínica , Avaliação Educacional , Feminino , Genótipo , Humanos , Masculino , Fenótipo , Autoavaliação (Psicologia) , Estudantes de Farmácia , Adulto Jovem
10.
J Pharm Pharm Sci ; 18(4): 713-27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26626255

RESUMO

PURPOSE: Delineate the selected pharmacodynamics of a naturally occurring stilbene 3'-Hydroxypterostilbene. OBJECTIVE: Characterize for the first time the pharmacodynamics bioactivity in several in-vitro assays with relevant roles in heart disease, inflammation, cancer, and diabetes etiology and pathophysiology. METHODS: 3'-Hydroxypterostilbene was studied in in-vitro assays to identify possible bioactivity. RESULTS: 3'-Hydroxypterostilbene demonstrated anti-oxidant, anti-inflammatory, cytotoxic, anti-adipogenic, histone deacetylase, and sirtuin-1 inhibitory activity. CONCLUSIONS: The importance of understanding individual stilbene pharmacologic activities were delineated. Small changes in chemical structure of stilbene compounds result in significant pharmacodynamic differences. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Estilbenos/farmacologia , Células 3T3-L1 , Adipogenia/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Histona Desacetilases/metabolismo , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Sirtuína 1/antagonistas & inibidores
11.
Phytother Res ; 29(8): 1168-79, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25939395

RESUMO

Studies were undertaken to evaluate the bioavailability in rats and content analysis of gnetol in Gnetum gnemon products reported to contain gnetol and to examine the pharmacological properties of gnetol in in vitro models including anti-inflammatory/analgesic, antidiabetic, anti-adipogenesis, and anticancer activity. Male Sprague-Dawley rats were cannulated and dosed either intravenously with gnetol (10 mg/kg) or orally (100 mg/kg). Various methanolic extractions of G. gnemon products were quantified. Gnetol's effect on cell viability in selected cell lines with or without inflammatory stimulus was assessed. α-Amylase and α-glucosidase inhibition was evaluated. Cyclooxygenase (COX)-1, COX-2, and histone deacetylase inhibition and adipogenesis inhibition were examined. After oral and intravenous administration, gnetol was detected in both serum and urine as the parent compound and as a glucuronidated metabolite. The bioavailability of gnetol was determined to be 6%. Gnetol is rapidly glucuronidated and is excreted in urine and via nonrenal routes. Gnetol was found to exist as an aglycone and as a glycoside in G. gnemon products. Gnetol showed concentration-dependent reductions in cell viability in cancer cell lines with greatest activity in colorectal cancer and potent COX-1, histone deacetylase, and weak COX-2 activities along with limited reduction in inflammation. Gnetol also possessed concentration-dependent alpha-amylase, alpha-glucosidase, and adipogenesis activities. Pretreatment of mice with gnetol was able to increase the latency period to response in analgesia models.


Assuntos
Inibidores Enzimáticos/farmacocinética , Análise de Alimentos , Gnetum/química , Estilbenos/farmacocinética , Animais , Antioxidantes/farmacologia , Disponibilidade Biológica , Linhagem Celular Tumoral , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2/farmacocinética , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Masculino , Proteínas de Membrana/antagonistas & inibidores , Camundongos , Dor/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Estilbenos/sangue , Estilbenos/urina , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases
12.
J Pharm Sci ; 101(10): 3787-98, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22806441

RESUMO

The histone deacetylase inhibitor suberoylanilide hydroxamic acid, known as vorinostat, is a promising anticancer drug with a unique mode of action; however, it is plagued by low water solubility, low permeability, and suboptimal pharmacokinetics. In this study, poly(ethylene glycol)-b-poly(DL-lactic acid) (PEG-b-PLA) micelles of vorinostat were developed. Vorinostat's pharmacokinetics in rats was investigated after intravenous (i.v.) (10 mg/kg) and oral (p.o.) (50 mg/kg) micellar administrations and compared with a conventional polyethylene glycol 400 solution and methylcellulose suspension. The micelles increased the aqueous solubility of vorinostat from 0.2 to 8.15 ± 0.60 and 10.24 ± 0.92 mg/mL at drug to nanocarrier ratios of 1:10 and 1:15, respectively. Micelles had nanoscopic mean diameters of 75.67 ± 7.57 and 87.33 ± 8.62 nm for 1:10 and 1:15 micelles, respectively, with drug loading capacities of 9.93 ± 0.21% and 6.91 ± 1.19%, and encapsulation efficiencies of 42.74 ± 1.67% and 73.29 ± 4.78%, respectively. The micelles provided sustained exposure and improved pharmacokinetics characterized by a significant increase in serum half-life, area under curve, and mean residence time. The micelles reduced vorinostat clearance particularly after i.v. dosing. Thus, PEG-b-PLA micelles significantly improved the p.o. and i.v. pharmacokinetics and bioavailability of vorinostat, which warrants further investigation.


Assuntos
Ácidos Hidroxâmicos/química , Ácidos Hidroxâmicos/farmacocinética , Lactatos/química , Nanopartículas/química , Polietilenoglicóis/química , Animais , Disponibilidade Biológica , Preparações de Ação Retardada , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Meia-Vida , Ácidos Hidroxâmicos/sangue , Ácidos Hidroxâmicos/urina , Lactatos/administração & dosagem , Masculino , Metilcelulose/administração & dosagem , Metilcelulose/química , Micelas , Nanopartículas/administração & dosagem , Tamanho da Partícula , Polietilenoglicóis/administração & dosagem , Ratos , Ratos Sprague-Dawley , Solubilidade , Suspensões/administração & dosagem , Suspensões/química , Suspensões/farmacocinética , Vorinostat
13.
Biomed Chromatogr ; 26(5): 606-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21898475

RESUMO

A method for analysis of lacosamide [(R)-2-acetamido-N-benzyl-3-methoxypropionamide] is needed for both human and veterinary pharmacokinetic investigations. While lacosamide is currently used to manage partial-onset seizures in humans suffering from epilepsy, it is also presently being investigated for use in the treatment of canine epilepsy in veterinary medicine. Currently, no dosing regimen for the drug exists in dogs. A novel and simple high-performance liquid chromatography method was developed for determination of lacosamide in dog serum. Serum proteins (0.1 mL) were precipitated with -20.0°C acetonitrile after addition of the internal standard, daidzein. Separation was achieved with a Phenomenex® Luna® C18 (2) (5 µm, 250 × 4.60 mm) column with ultraviolet detection at 210 nm. The calibration curves were linear ranging from 0.5 to 25 µg/mL. Precision of the assay was <13% (RSD) and was within 12% for all points in the calibration curve. The limit of quantitation for this method was 0.5 µg/mL. The assay was applied successfully to a pre-clinical study of lacosamide pharmacokinetics in dogs.


Assuntos
Acetamidas/sangue , Anticonvulsivantes/sangue , Cromatografia Líquida de Alta Pressão/métodos , Cães/sangue , Espectrofotometria Ultravioleta/métodos , Acetamidas/farmacocinética , Animais , Anticonvulsivantes/farmacocinética , Cromatografia de Fase Reversa , Estabilidade de Medicamentos , Lacosamida , Modelos Lineares
14.
Pharmaceutics ; 5(1): 81-93, 2012 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24300398

RESUMO

The rapamycin analog, ridaforolimus, has demonstrated potent anti-proliferative effects in cancer treatment, and it currently is being evaluated in a range of clinical cancer studies. Ridaforolimus is an extremely lipophilic compound with limited aqueous solubility, which may benefit from formulation with polymeric micelles. Herein, we report the encapsulation of ridaforolimus in 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy-poly(ethylene glycol 2000) (DSPE-PEG2000) via a solvent extraction technique. Micelle loading greatly improved the solubility of ridaforolimus by approximately 40 times from 200 µg/mL to 8.9 mg/mL. The diameters of the drug-loaded micelles were 33 ± 15 nm indicating they are of appropriate size to accumulate within the tumor site via the enhanced permeability and retention (EPR) effect. The DSPE-PEG2000 micelle formulation was dosed intravenously to rats at 10 mg/kg and compared to a control of ridaforolimus in ethanol/PEG 400. The micelle significantly increased the half-life of ridaforolimus by 170% and decreased the clearance by 58%, which is consistent with improved retention of the drug in the plasma by the micelle formulation.

15.
Ther Deliv ; 2(5): 643-72, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21837267

RESUMO

Flip-flop pharmacokinetics is a phenomenon often encountered with extravascularly administered drugs. Occurrence of flip-flop spans preclinical to human studies. The purpose of this article is to analyze both the pharmacokinetic interpretation errors and opportunities underlying the presence of flip-flop pharmacokinetics during drug development. Flip-flop occurs when the rate of absorption is slower than the rate of elimination. If it is not recognized, it can create difficulties in the acquisition and interpretation of pharmacokinetic parameters. When flip-flop is expected or discovered, a longer duration of sampling may be necessary in order to avoid overestimation of fraction of dose absorbed. Common culprits of flip-flop disposition are modified dosage formulations; however, formulation characteristics such as the drug chemical entities themselves or the incorporated excipients can also cause the phenomenon. Yet another contributing factor is the physiological makeup of the extravascular site of administration. In this article, these causes of flip-flop pharmacokinetics are discussed with incorporation of relevant examples and the implications for drug development outlined.


Assuntos
Descoberta de Drogas , Farmacocinética , Humanos
16.
Chirality ; 23(4): 339-48, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21384439

RESUMO

The chirality of flavonoids has been overlooked in the majority of pharmacokinetic studies of homoeriodictyol, isosakuranetin, and taxifolin. The stereospecific pharmacokinetic disposition of these xenobiotics in male Sprague-Dawley rats is described for the first time. Validated HPLC methods were used to analyze serum and urine samples of rats following intravenous administration of each flavonoid via jugular vein cannulation and to determine their content in selected fruits. The characterization and interpretation of the pharmacokinetic disposition profiles of homoeriodictyol, isosakuranetin, and taxifolin are described. A discrepancy exists between half-lives in serum and urine which may be attributed to low assay sensitivity in serum for the three compounds; thus, a more accurate estimation of the pharmacokinetic parameters was obtained from urine. The pharmacokinetics of homoeriodictyol, isosakuranetin, and taxifolin revealed distribution, metabolism, and elimination that were dependent on the stereochemistry of the stereoisomers. The (-)-(S)-enantiomers of homoeriodictyol and isosakuranetin and the (+)-(2S; 3R)-stereoisomer of taxifolin were predominant in lemon, grapefruit, and tomato. These findings were achieved using chiral methods of analysis; the utility and necessity of developing chiral methods of analysis for chiral xenobiotics are discussed.


Assuntos
Flavonas/análise , Flavonas/farmacocinética , Flavonoides/análise , Flavonoides/farmacocinética , Frutas/química , Quercetina/análogos & derivados , Animais , Área Sob a Curva , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Meia-Vida , Masculino , Estrutura Molecular , Quercetina/análise , Quercetina/farmacocinética , Ratos , Ratos Sprague-Dawley , Soro/química , Estereoisomerismo , Urina/química
17.
J Pharm Biomed Anal ; 54(4): 878-81, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21126844

RESUMO

A method of analysis of gnetol (2,3',5',6-tetrahydroxy-trans-stilbene) in biological fluids is necessary for the study of its kinetics and disposition in plants. A simple high-performance liquid chromatography (HPLC) method was developed for the determination of gnetol in rat serum using a reverse-phase, isocratic system. Separation was achieved using a Phenomenex® Luna C18(2) column with ultraviolet detection at 305 nm. The standard curves were linear ranging from 0.5 to 100 µg/ml. The mean extraction efficiency was >90.5%. Precision of the assay was <14% (R.S.D.), and was within 14% at the limit of quantitation (0.5 µg/ml). Bias of the assay was lower than 15%, and was within 15% at the limit of quantitation. The assay was applied successfully to the study of serum disposition of gnetol in rats.


Assuntos
Anti-Inflamatórios não Esteroides/sangue , Anti-Inflamatórios não Esteroides/farmacocinética , Estilbenos/sangue , Estilbenos/farmacocinética , Animais , Calibragem , Cromatografia Líquida de Alta Pressão , Meia-Vida , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
18.
Biomed Chromatogr ; 24(5): 516-21, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19739255

RESUMO

A high-performance liquid chromatographic (HPLC) method was developed for the analysis of the stilbene, oxyresveratrol. This method involves the use of a Luna C(18) column with ultraviolet detection at 320 nm. The mobile phase consisted of acetonitrile, water and formic acid (30 : 70 : 0.04 v/v) with a flow rate of 0.6 mL/min. The calibration curves were linear over the range of 0.5-100.0 microg/mL. The mean extraction efficiency was between 98.9 and 109%. The precision of the assay was 0.069-18.4% (RSD%), and within 20% at the limit of quantitation (0.5 microg/mL). The bias of the assay was <15% and within 15% at the limit of quantitation. This assay was successfully applied to pre-clinical pharmacokinetic samples from rat urine and to nutraceutical product analysis.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Extratos Vegetais/análise , Extratos Vegetais/urina , Estilbenos/análise , Estilbenos/urina , Animais , Limite de Detecção , Masculino , Ratos , Ratos Sprague-Dawley
19.
Biomed Chromatogr ; 24(5): 556-61, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19795393

RESUMO

To study the intracellular metabolism of the prodrug 5-fluorocytosine (5FC), we developed a novel reverse-phase high-performance liquid chromatography method to simultaneously detect 5FC and its four major anabolic metabolites: 5-fluorouracil, 5-fluorouridine, 5-fluorouridine-monophosphate and 5-fluoro-2'deoxyuridine-5'-monophosphate. Separation of each compound was accomplished under isocratic conditions using a C(18) column and mobile phase of formic acid-water (1 : 99 v/v). The method was validated for both accuracy and reproducibility in cell culture media. Additionally, metabolites were assessed for stability at ambient temperatures and following freeze-thaw cycles. Calibration curves were linear over a range of 1-200 microg/mL. Limit of quantification for four of the five compounds was 1 microg/mL in cell culture media (RSD < 11%). This method was successfully used to monitor intracellular conversion of 5FC to its metabolic products over a 24h period.


Assuntos
Antimetabólitos Antineoplásicos/análise , Antimetabólitos Antineoplásicos/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Flucitosina/análise , Flucitosina/metabolismo , Animais , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/economia , Ratos , Sensibilidade e Especificidade , Fatores de Tempo
20.
Pharmaceutics ; 2(1): 50-60, 2010 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-27721342

RESUMO

Label claims of vitamin E succinate and polyphenolic nutraceuticals are assessed. A validated HPLC method was utilized to assess vitamin E succinate products. Three novel LC/MS methods were used to assess the polyphenols, pterostilbene, phloretin, and myricetin, in dietary supplements. The amount of vitamin E succinate varied from 0-130% of the stated label content with two products containing vitamin E acetate rather than vitamin E succinate. Expected polyphenols were found in 7 of the 8 supplement products. None of the polyphenol supplements contained content within 100-120% of label claims. The present study indicates a lack of uniformity in nutraceutical products.

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