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1.
J Microbiol Biol Educ ; 24(3)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38108014

RESUMEN

This case study was designed to help students explore the molecular mechanisms of the spliceosome and how SARS-CoV-2 impacts host cell spliceosomal function while interpreting figures from primary literature (A. K. Banjeree, et al., Cell 183:1325-1339, e1-e10, 2020, https://doi.org/10.1016/j.cell.2020.10.004). "Pete and the Missing Scissors" was designed and implemented in the spring of 2022 and fall of 2022 in two large-enrollment (150+) introductory molecular biology courses at a large, public research institution. The case study was formatted in alignment with the National Center for Case Study Teaching in Science (NCCSTS) framework, which has been shown to be an effective, student-centered approach to teaching complex biological concepts at the undergraduate level. The case study had four student learning objectives (SLOs) that aligned with Bloom's Revised Taxonomy and required students to develop an understanding of the molecular mechanisms of splicing and analyze and interpret a figure from primary literature. Both formative and summative assessment questions are included in this activity, with each question mapping to one of the case study SLOs. Summative assessment questions were given in a pre-/post-manner, and a paired t-test was used to evaluate differences between students' pre- and post-assessment scores. Assessment results demonstrated that students in both courses mastered each of the SLOs of this case study, given the significant increase in post-assessment scores compared to the pre-assessment. These findings indicate that the "Pete and the Missing Scissors" case study is an effective approach to develop students' understanding of the spliceosome, as well as ability to interpret figures from primary literature.

2.
Front Microbiol ; 13: 966289, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36620056

RESUMEN

The gut microbiome and its physiological impacts on human and animal health is an area of research emphasis. Microbes themselves are invisible and may therefore be abstract and challenging to understand. It is therefore important to infuse this topic into undergraduate curricula, including Anatomy and Physiology courses, ideally through an active learning approach. To accomplish this, we developed a novel tactile teaching tool with guided-inquiry (TTT-GI) activity where students explored how the gut microbiome ferments carbohydrates to produce short chain fatty acids (SCFAs). This activity was implemented in two sections of a large-enrollment Human Anatomy and Physiology course at a research intensive (R1) university in the Spring of 2022 that was taught using a hyflex format. Students who attended class in person used commonly available building toys to assemble representative carbohydrates of varying structural complexity, whereas students who attended class virtually made these carbohydrate structures using a digital learning tool. Students then predicted how microbes within the gut would ferment different carbohydrates into SCFAs, as well as the physiological implications of the SCFAs. We assessed this activity to address three research questions, with 182 students comprising our sample. First, we evaluated if the activity learning objectives were achieved through implementation of a pre-and post-assessment schema. Our results revealed that all three learning objectives of this activity were attained. Next, we evaluated if the format in which this TTT-GI activity was implemented impacted student learning. While we found minimal and nonsignificant differences in student learning between those who attended in-person and those who attended remotely, we did find significant differences between the two course sections, which differed in length and spacing of the activity. Finally, we evaluated if this TTT-GI approach was impactful for diverse students. We observed modest and nonsignificant positive learning gains for some populations of students traditionally underrepresented in STEM (first-generation students and students with one or more disabilities). That said, we found that the greatest learning gains associated with this TTT-GI activity were observed in students who had taken previous upper-level biology coursework.

3.
Ethn Dis ; 30(4): 681-692, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32989368

RESUMEN

Objective: The biomedical/behavioral sciences lag in the recruitment and advancement of students from historically underrepresented backgrounds. In 2014 the NIH created the Diversity Program Consortium (DPC), a prospective, multi-site study comprising 10 Building Infrastructure Leading to Diversity (BUILD) institutional grantees, the National Research Mentoring Network (NRMN) and a Coordination and Evaluation Center (CEC). This article describes baseline characteristics of four incoming, first-year student cohorts at the primary BUILD institutions who completed the Higher Education Research Institute, The Freshmen Survey between 2015-2019. These freshmen are the primary student cohorts for longitudinal analyses comparing outcomes of BUILD program participants and non-participants. Design: Baseline description of first-year students entering college at BUILD institutions during 2015-2019. Setting: Ten colleges/universities that each received <$7.5mil/yr in NIH Research Project Grants and have high proportions of low-income students. Participants: First-year undergraduate students who participated in BUILD-sponsored activities and a sample of non-BUILD students at the same BUILD institutions. A total of 32,963 first-year students were enrolled in the project; 64% were female, 18% Hispanic/Latinx, 19% African American/Black, 2% American Indian/Alaska Native and Native Hawaiian/Pacific Islander, 17% Asian, and 29% White. Twenty-seven percent were from families with an income <$30,000/yr and 25% were their family's first generation in college. Planned Outcomes: Primary student outcomes to be evaluated over time include undergraduate biomedical degree completion, entry into/completion of a graduate biomedical degree program, and evidence of excelling in biomedical research and scholarship. Conclusions: The DPC national evaluation has identified a large, longitudinal cohort of students with many from groups historically underrepresented in the biomedical sciences that will inform institutional/national policy level initiatives to help diversify the biomedical workforce.


Asunto(s)
Investigación Biomédica/educación , Diversidad Cultural , Programas de Gobierno/estadística & datos numéricos , Estudiantes/estadística & datos numéricos , Universidades , Adolescente , Adulto , Negro o Afroamericano/estadística & datos numéricos , Asiático/estadística & datos numéricos , Escolaridad , Femenino , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Renta/estadística & datos numéricos , Masculino , Persona de Mediana Edad , National Institutes of Health (U.S.)/economía , Nativos de Hawái y Otras Islas del Pacífico/estadística & datos numéricos , Estudios Prospectivos , Encuestas y Cuestionarios , Estados Unidos , Población Blanca/estadística & datos numéricos , Recursos Humanos , Adulto Joven , Indio Americano o Nativo de Alaska/estadística & datos numéricos
4.
UI J ; 11(1)2020.
Artículo en Inglés | MEDLINE | ID: mdl-32766571

RESUMEN

The benefits of mentored undergraduate research to student success, retention, and persistence in science, technology, engineering, and mathematics (STEM) have long been identified. However, many students miss out on the opportunity to engage in research often due to unfamiliarity of various research opportunities or how to approach potential research mentors. To address this, we developed a scalable online badge, Introduction to Research, that draws on aspects of the Entering Research curriculum (Branchaw, Pfund, & Rediske, 2010) to help students explore and prepare for undergraduate research in the biomedical and behavioral sciences. Students in the BUILD Training Program, part of the larger STEM BUILD at UMBC Initiative, completed the badge in conjunction with a 3-week classroom-based undergraduate research experience (CURE) before the start of their second year of undergraduate study at the University of Maryland, Baltimore County (UMBC). We were interested in investigating how this intervention, online badge plus CURE, correlated to students engaging in undergraduate research before the end of their second year at UMBC. We did this through student self-report, comparing students who had participated in the online badge plus CURE (BTP) to those who participated in neither (Control). Our data demonstrate that students who participated in the Introduction to Research Badge and CURE entered into mentored research at a significantly higher rate than students who were exposed to neither. Further, previously validated instruments of students 'research self-efficacy and science identity were used to compare how the Introduction to Research Badge and CURE may impact these two psycho-social variables. Students who participated in the Introduction to Research Badge and CURE had significantly higher gains in research self-efficacy compared to the control group. However, no change was observed in science identity for either group. Collectively, our results suggest that students who engage in the Introduction to Research Badge in combination with a CURE engage in mentored research within a year of completion at higher levels than students who engage in neither.

5.
Artículo en Inglés | MEDLINE | ID: mdl-32313592

RESUMEN

Deaf undergraduates are eager to engage in research but often feel marginalized due to lack of appropriate accommodations to allow for effective communication within heterogeneous research teams consisting of hearing peers and/or mentors. In this case study, we interviewed four American Sign Language (ASL) interpreters who provided full-time accommodations to teams consisting of one deaf student and two hearing peers during a six-week internship. We queried the interpreters on their role and experiences in supporting the research teams. Our findings indicate that the interpreters can be a valuable asset to heterogeneous teams by supporting both deaf and hearing individuals and advocating for the deaf student. That said, interpreters also had to overcome challenges unique to interpreting in the research environment, such as deciding when and how to interpret. The insights provided by the interpreters interviewed here are valuable as undergraduate research programs evaluate how to provide appropriate accommodations to deaf students engaged in research. In addition, they also highlight the need for research experience coordinators and mentors to consider supporting diverse teams in developing effective communication strategies and applying universal design for learning to the research environment.

6.
Biochem Mol Biol Educ ; 48(4): 391-403, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32294307

RESUMEN

Metagenomics is a tool that enables researchers to study genetic material recovered directly from microbial communities or microbiomes. Fueled by advances in sequencing technologies, bioinformatics tools, and sample processing, metagenomics studies promise to expand our understanding of human health and the use of microorganisms for agriculture and industry. Therefore, teaching students about metagenomics is crucial to prepare them for modern careers in the life sciences. However, the increasing number of different approaches makes teaching metagenomics to students a challenge. This 8-week metagenomics laboratory course has the objective of introducing upper-level undergraduate and graduate students to strategies for designing, executing, and analyzing microbiome investigations. The laboratory component begins with sample processing, library preparation, and submission for high-throughput sequencing before transitioning to computer-based activities, which include an introduction to several fundamental computational metagenomics tools. Students analyze their sequencing results and deposit findings in sequence databases. The laboratory component is complemented by a weekly lecture, where active learning sessions promote retrieval practice and allow students to reflect on and diagram processes performed in the laboratory. Attainment of student learning outcomes was assessed through the completion of various course assignments: laboratory reports, presentations, and a cumulative final exam. Further, students' perceptions of their gains relevant to the learning outcomes were evaluated using pre- and postcourse surveys. Collectively, these data demonstrate that this course results in the attainment of the learning outcomes and that this approach provides an adaptable way to expose students to the cutting-edge field of metagenomics.


Asunto(s)
Bacterias/genética , Biología Computacional/métodos , Metagenómica/educación , Microbiota , Aprendizaje Basado en Problemas/métodos , ARN Bacteriano/análisis , ARN Ribosómico 16S/análisis , Bacterias/clasificación , Bacterias/aislamiento & purificación , Genoma Bacteriano , Humanos , Metagenómica/métodos , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Microbiología del Suelo , Estudiantes
7.
J Coll Sci Teach ; 47(4): 83-91, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29681667

RESUMEN

Using a cooperative learning framework in a quantitative reasoning laboratory course, students were assigned to static teams of four in which they adopted roles that rotated regularly. The roles included: team leader, protocol manager, data recorder, and researcher. Using a mixed-methods approach, we investigated students' perceptions of the team roles and specifically addressed students' understanding of the roles, students' beliefs in their ability to enact the roles, and whether working with assigned team roles supported the teams to work effectively and cohesively. Although students expressed confidence in their understanding of the team roles, their understanding differed from the initial descriptions. This suggests that students' understanding of team roles may be influenced by a variety of factors, including their experiences within their teams. Students also reported that some roles appeared to lack a purpose, implying that for roles to be successful, they must have a clear purpose. Finally, the fact that many students reported ignoring the team roles suggests that students do not perceive roles as a requirement for team productivity and cohesion. On the basis of these findings, we provide recommendations for instructors wishing to establish a classroom group laboratory environment.

8.
J Young Investig ; 35(6): 92-96, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31097926

RESUMEN

Etheostoma is a genus of North American darter fish whose species have similar habitats and breeding seasons, yet hybridization is rare. Behavioral barriers have been demonstrated to play a key role in maintaining species boundaries. Further, conspecific (same species) sperm precedence has also been observed when the gametes of two different species come into contact. In this study, we investigated if physical characteristics of sperm could be a mechanism for the lower fertilization success of heterospecific (different species) males when eggs are simultaneously exposed to conspecific and heterospecific sperm. We chose to examine the sperm of two closely related species, E. zonale and E. barrenense. Using toluidine blue and immunofluorescent labeling methods, we compared head diameter and tail length of sperm cells between the two species. We found that head diameter was significantly larger for E. barrenense sperm compared to E. zonale. This difference in cell morphology may point to a physical mechanism underlying conspecific sperm precedence in Etheostoma. Our results are the first to describe a morphological difference in sperm between species in this genus and provide initial evidence for the role of sperm morphology in prezygotic reproductive isolation.

9.
Artículo en Inglés | MEDLINE | ID: mdl-28861131

RESUMEN

Metagenomics is an important method for studying microbial life. However, undergraduate exposure to metagenomics is hindered by associated software, computing demands, and dataset access. In this inquiry-based activity designed for introductory life science majors and nonmajors, students perform an investigation of the bacterial communities inhabiting the human belly button and associated metagenomics data collected through a citizen science project and visualized using an open-access bioinformatics tool. The activity is designed for attainment of the following student learning outcomes: defining terms associated with metagenomics analyses, describing the biological impact of the microbiota on human health, formulating a hypothesis, analyzing and interpreting metagenomics data to compare microbiota, evaluating a specific hypothesis, and synthesizing a conceptual model as to why bacterial populations vary. This activity was implemented in six introductory biology and biotechnology courses across five institutions. Attainment of student learning outcomes was assessed through completion of a quiz and students' presentations of their findings. In presentations, students demonstrated their ability to develop novel hypotheses and analyze and interpret metagenomic data to evaluate their hypothesis. In quizzes, students demonstrated their ability to define key terms and describe the biological impact of the microbiota on human health. Student learning gains assessment also revealed that students perceived gains for all student learning outcomes. Collectively, our assessment demonstrates achievement of the learning outcomes and supports the utility of this inquiry-based activity to engage undergraduates in the scientific process via analyses of metagenomics datasets and associated exploration of a microbial community that lives on the human body.

10.
Sports Med ; 47(10): 2045-2068, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28386652

RESUMEN

BACKGROUND: Proficiency in fundamental movement skills (FMS) lays the foundation for being physically active and developing more complex motor skills. Improving these motor skills may provide enhanced opportunities for the development of a variety of perceptual, social, and cognitive skills. OBJECTIVE: The objective of this systematic review and meta-analysis was to assess the effects of FMS interventions on actual FMS, targeting typically developing young children. METHOD: Searches in seven databases (CINAHL, Embase, MEDLINE, PsycINFO, PubMed, Scopus, Web of Science) up to August 2015 were completed. Trials with children (aged 2-6 years) in childcare or kindergarten settings that applied FMS-enhancing intervention programs of at least 4 weeks and meeting the inclusion criteria were included. Standardized data extraction forms were used. Risk of bias was assessed using a standard scoring scheme (Effective Public Health Practice Project-Quality Assessment Tool for Quantitative Studies [EPHPP]). We calculated effects on overall FMS, object control and locomotor subscales (OCS and LMS) by weighted standardized mean differences (SMDbetween) using random-effects models. Certainty in training effects was evaluated using GRADE (Grading of Recommendations Assessment, Development, and Evaluation System). RESULTS: Thirty trials (15 randomized controlled trials and 15 controlled trials) involving 6126 preschoolers (aged 3.3-5.5 years) revealed significant differences among groups in favor of the intervention group (INT) with small-to-large effects on overall FMS (SMDbetween 0.46), OCS (SMDbetween 1.36), and LMS (SMDbetween 0.94). Our certainty in the treatment estimates based on GRADE is very low. CONCLUSIONS: Although there is relevant effectiveness of programs to improve FMS proficiency in healthy young children, they need to be interpreted with care as they are based on low-quality evidence and immediate post-intervention effects without long-term follow-up.


Asunto(s)
Ejercicio Físico , Actividad Motora/fisiología , Destreza Motora/fisiología , Movimiento/fisiología , Niño , Preescolar , Humanos , Instituciones Académicas , Estudiantes
11.
BMC Proc ; 11(Suppl 12): 24, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29375665

RESUMEN

BACKGROUND: UMBC, a diverse public research university, "builds" upon its reputation in producing highly capable undergraduate scholars to create a comprehensive new model, STEM BUILD at UMBC. This program is designed to help more students develop the skills, experience and motivation to excel in science, technology, engineering, and mathematics (STEM). This article provides an in-depth description of STEM BUILD at UMBC and provides the context of this initiative within UMBC's vision and mission. KEY HIGHLIGHTS: The STEM BUILD model targets promising STEM students who enter as freshmen or transfer students and do not qualify for significant university or other scholarship support. Of primary importance to this initiative are capacity, scalability, and institutional sustainability, as we distill the advantages and opportunities of UMBC's successful scholars programs and expand their application to more students. The general approach is to infuse the mentoring and training process into the fabric of the undergraduate experience while fostering community, scientific identity, and resilience. At the heart of STEM BUILD at UMBC is the development of BUILD Group Research (BGR), a sequence of experiences designed to overcome the challenges that undergraduates without programmatic support often encounter (e.g., limited internship opportunities, mentorships, and research positions for which top STEM students are favored). BUILD Training Program (BTP) Trainees serve as pioneers in this initiative, which is potentially a national model for universities as they address the call to retain and graduate more students in STEM disciplines - especially those from underrepresented groups. As such, BTP is a research study using random assignment trial methodology that focuses on the scalability and eventual incorporation of successful measures into the traditional format of the academy. IMPLICATIONS: Critical measures to transform institutional culture include establishing an extensive STEM Living and Learning Community to increase undergraduate retention, expanding the adoption of "active learning" pedagogies to increase the efficiency of learning, and developing programs to train researchers to effectively mentor a greater portion of the student population. The overarching goal of STEM BUILD at UMBC is to retain students in STEM majors and better prepare them for post baccalaureate, graduate, or professional programs as well as careers in biomedical and behavioral research.

12.
J Microbiol Biol Educ ; 17(3): 451-457, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28101273

RESUMEN

This introductory laboratory exercise gives first-year life science majors or nonmajors an opportunity to gain knowledge and experience in basic bioinformatics and molecular biology laboratory techniques and analysis in the context of a mock crime scene investigation. In this laboratory, students determine if a human (Lady) or dog (Kona) committed the fictional crime of scaring a cat. Students begin by performing in silico PCR using provided dog- and human-specific PCR primers to determine the sequences to be amplified and predict PCR amplicon sizes. They then BLAST (Basic Local Alignment Search Tool) the in silico PCR results to confirm that the PCR primers are designed to amplify genomic fragments of the cardiac actin gene in both dogs and humans. Finally, they use DNA quantification techniques, PCR, and agarose gel electrophoresis to identify the culprit and they confirm results by analyzing Sanger sequencing. Student learning gains were demonstrated by successful execution of the lab and by analysis and interpretation of data in the completion of laboratory reports. The student learning gains were also demonstrated by increased performance on a post-laboratory assessment compared to the pre-assessment. A post-activity assessment also revealed that students perceived gains in the skills and conceptual knowledge associated with the student learning outcomes. Finally, assessment of this introductory molecular biology and bio-informatics activity reveals that it allows first-year students to develop higher-order data analysis and interpretation skills.

13.
Biomed Res Int ; 2015: 359392, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26504802

RESUMEN

BACKGROUND: In this study, we investigated the prognostic role of homotypic tumor cell cannibalism in different cancer types. METHODS: The phenomenon of one cell being internalized into another, which we refer to as "cell-in-cell event," was assessed in 416 cases from five head and neck cancer cohorts, as well as one anal and one rectal cancer cohort. The samples were processed into tissue microarrays and immunohistochemically stained for E-cadherin and cleaved caspase-3 to visualize cell membranes and apoptotic cell death. RESULTS: Cell-in-cell events were found in all of the cohorts. The frequency ranged from 0.7 to 17.3 cell-in-cell events per mm(2). Hardly any apoptotic cells were found within the cell-in-cell structures, although apoptotic cell rates were about 1.6 to two times as high as cell-in-cell rates of the same tissue sample. High numbers of cell-in-cell events showed adverse effects on patients' survival in the head and neck and in the rectal cancer cohorts. In multivariate analysis, high frequency was an adverse prognostic factor for overall survival in patients with head and neck cancer (p = 0.008). CONCLUSION: Cell-in-cell events were found to predict patient outcomes in various types of cancer better than apoptosis and proliferation and might therefore be used to guide treatment strategies.


Asunto(s)
Neoplasias/patología , Fagocitos/patología , Anciano , Neoplasias del Ano/metabolismo , Neoplasias del Ano/mortalidad , Neoplasias del Ano/patología , Apoptosis , Cadherinas/metabolismo , Caspasa 3/metabolismo , Proliferación Celular , Estudios de Cohortes , Femenino , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Neoplasias/metabolismo , Neoplasias/mortalidad , Fagocitos/metabolismo , Fagocitosis , Pronóstico , Neoplasias del Recto/metabolismo , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología
14.
Biochem Mol Biol Educ ; 42(5): 382-97, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25051922

RESUMEN

Flow cytometry and enzyme-linked immunosorbent assay (ELISA) are commonly used techniques associated with clinical and research applications within the immunology and medical fields. The use of these techniques is becoming increasingly valuable in many life science and engineering disciplines as well. Herein, we report the development and evaluation of a novel half-semester course that focused on introducing undergraduate and graduate students to advance conceptual and technical skills associated with flow cytometry and ELISA, with emphasis on applications, experimental design, and data analysis. This course was offered in the North Carolina State University Biotechnology Program over three semesters and consisted of weekly lectures and laboratories. Students performed and/or analyzed flow cytometry and ELISA in three separate laboratory exercises: (1) identification of transgenic zebrafish hematopoietic cells, (2) analysis of transfection efficiency, and (3) analysis of cytokine production upon lipopolysaccharide stimulation. Student learning outcomes were achieved as demonstrated by multiple means of assessment, including three laboratory reports, a data analysis laboratory practicum, and a cumulative final exam. Further, anonymous student self-assessment revealed increased student confidence in the knowledge and skill sets defined in the learning outcomes.


Asunto(s)
Alergia e Inmunología/educación , Curriculum , Ensayo de Inmunoadsorción Enzimática/métodos , Citometría de Flujo/métodos , Alergia e Inmunología/instrumentación , Biotecnología/educación , Biotecnología/instrumentación , Educación de Postgrado , Humanos , Reproducibilidad de los Resultados , Programas de Autoevaluación , Estudiantes , Enseñanza/métodos , Materiales de Enseñanza , Universidades
15.
PLoS One ; 8(6): e66512, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23840497

RESUMEN

Myristoylated alanine-rich C-kinase substrate (MARCKS) is a ubiquitously expressed substrate of protein kinase C (PKC) that is involved in reorganization of the actin cytoskeleton. We hypothesized that MARCKS is involved in regulation of fibroblast migration and addressed this hypothesis by utilizing a unique reagent developed in this laboratory, the MANS peptide. The MANS peptide is a myristoylated cell permeable peptide corresponding to the first 24-amino acids of MARCKS that inhibits MARCKS function. Treatment of NIH-3T3 fibroblasts with the MANS peptide attenuated cell migration in scratch wounding assays, while a myristoylated, missense control peptide (RNS) had no effect. Neither MANS nor RNS peptide treatment altered NIH-3T3 cell proliferation within the parameters of the scratch assay. MANS peptide treatment also resulted in inhibited NIH-3T3 chemotaxis towards the chemoattractant platelet-derived growth factor-BB (PDGF-BB), with no effect observed with RNS treatment. Live cell imaging of PDGF-BB induced chemotaxis demonstrated that MANS peptide treatment resulted in weak chemotactic fidelity compared to RNS treated cells. MANS and RNS peptides did not affect PDGF-BB induced phosphorylation of MARCKS or phosphoinositide 3-kinase (PI3K) signaling, as measured by Akt phosphorylation. Further, no difference in cell migration was observed in NIH-3T3 fibroblasts that were transfected with MARCKS siRNAs with or without MANS peptide treatment. Genetic structure-function analysis revealed that MANS peptide-mediated attenuation of NIH-3T3 cell migration does not require the presence of the myristic acid moiety on the amino-terminus. Expression of either MANS or unmyristoylated MANS (UMANS) C-terminal EGFP fusion proteins resulted in similar levels of attenuated cell migration as observed with MANS peptide treatment. These data demonstrate that MARCKS regulates cell migration and suggests that MARCKS-mediated regulation of fibroblast migration involves the MARCKS amino-terminus. Further, this data demonstrates that MANS peptide treatment inhibits MARCKS function during fibroblast migration and that MANS mediated inhibition occurs independent of myristoylation.


Asunto(s)
Quimiotaxis/fisiología , Fibroblastos/citología , Péptidos y Proteínas de Señalización Intracelular/fisiología , Proteínas de la Membrana/fisiología , Células 3T3 , Animales , Becaplermina , Quimiotaxis/efectos de los fármacos , Colágeno/metabolismo , Fibronectinas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Ratones , Sustrato de la Proteína Quinasa C Rico en Alanina Miristoilada , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-sis/farmacología
16.
J Immunol ; 189(4): 1765-72, 2012 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-22778391

RESUMEN

Graft-versus-host disease (GVHD) remains the most significant complication after allogeneic stem cell transplantation. Previously, acute GVHD had been considered to be mediated predominantly by Th1-polarized T cells. Recently, investigators have identified a second proinflammatory lineage of T cells termed Th17 that is critically dependent on the transcription factor retinoic acid-related orphan receptor (ROR)γt. In this study, we have evaluated the role of Th17 cells in murine acute GVHD by infusing donor T cells lacking RORC and as a consequence the isoform RORγt. Recipients given donor CD4(+) and CD8(+) T cells lacking RORC had significantly attenuated acute GVHD and markedly decreased tissue pathology in the colon, liver, and lung. Using a clinically relevant haploidentical murine transplantation model, we showed that RORC(-/-) CD4(+) T cells alone diminished the severity and lethality of acute GVHD. This was not found when CD4(+) T cells from RORC(-/-) mice were given to completely mismatched BALB/c mice, and it was correlated with absolute differences in the generation of TNF in the colon after transplant. Thus, CD4(+) T cell expression of RORC is important in the pathogenesis of acute GVHD.


Asunto(s)
Enfermedad Injerto contra Huésped/inmunología , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/inmunología , Células Th17/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Enfermedad Injerto contra Huésped/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
17.
J Drug Deliv ; 2012: 962101, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22363842

RESUMEN

A sustained-release DepoFoam injection formulation of bupivacaine (EXPAREL, 15 mg/mL) is currently being investigated for postsurgical analgesia via peripheral nerve block (PNB). Single-dose toxicology studies of EXPAREL (9, 18, and 30 mg/kg), bupivacaine solution (Bsol, 9 mg/kg), and saline injected around the brachial plexus nerve bundle were performed in rabbits and dogs. The endpoints included clinical pathology, pharmacokinetics, and histopathology evaluation on Day 3 and Day 15 (2/sex/group/period). EXPAREL resulted in a nearly 4-fold lower C(max) versus Bsol at the same dose. EXPAREL was well tolerated at doses up to 30 mg/kg. The only EXPAREL-related effect seen was minimal to mild granulomatous inflammation of adipose tissue around nerve roots (8 of 24 rabbits and 7 of 24 dogs) in the brachial plexus sites. The results indicate that EXPAREL was well tolerated in these models and did not produce nerve damage after PNB in rabbits and dogs.

18.
J Drug Deliv ; 2011: 467429, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22013534

RESUMEN

EXPAREL (bupivacaine extended-release liposome injection), DepoFoam bupivacaine, is in development for prolonged postsurgical analgesia. Repeat-dose toxicity studies were conducted in rabbits and dogs to compare the potential local and systemic toxicities of EXPAREL and bupivacaine HCl (Bsol), and the reversibility of any effects. Dogs tolerated much larger doses than rabbits. EXPAREL-related minimal-to-moderate granulomatous inflammation was noted at the injection sites. In recovery animals, the granulomatous inflammation was observed less frequently and was characterized by an increased number of multinucleated giant cells. These effects were considered a normal response to liposomes and nonadverse. Rabbits are more sensitive than dogs. In rabbits, convulsions were noted with EXPAREL and more frequently with Bsol; a NOAEL was not identified. In dogs, EXPAREL was well tolerated (NOAEL > 30 mg/kg/dose). The cumulative exposure of EXPAREL in these studies is well in excess of the proposed maximum single-dose exposure that is intended in humans.

19.
Expert Opin Investig Drugs ; 20(10): 1327-41, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21867476

RESUMEN

OBJECTIVE: DepoFoam bupivacaine (DB) is in development for prolonged postoperative analgesia. Studies were conducted to evaluate the potential local and systemic toxicity and any effect on wound healing after wound infiltration. METHODS: The model simulates an inguinal hernia (skin incision ∼2.5 and 5.5 cm). Animals (four/sex/group of each species) received DB 9, 18 or either 25 or 30 mg/kg, bupivacaine solution (B(sol); 7.5 mg/ml, 9 mg/kg) or saline. DB was given at 0.6, 1.2 and 1.0 or 1.2 ml/kg, respectively, and B(sol) or saline at 1.2 ml/kg. Each dose was infiltrated in small fractions on Day 1. End points included histology on Days 3 and 15. Wound healing was recorded on Day 2 through Day 15. RESULTS: There was no adverse effect in either species. Notably, granulomatous inflammation was noted in surgical sites from 8 of 24 rabbits in the DB groups only. Based on the minimal to mild severity on Day 15, this was considered a normal reaction against the liposomes. Except for granulomatous inflammation, there were no differences in overall incidence or severity of histologic changes in the sites dosed to DB, saline or B(sol). CONCLUSIONS: The data reported here are the first demonstration of the safety of DB in toxicology species.


Asunto(s)
Anestésicos Locales/farmacología , Bupivacaína/farmacología , Dolor Postoperatorio/tratamiento farmacológico , Anestésicos Locales/administración & dosificación , Anestésicos Locales/farmacocinética , Anestésicos Locales/uso terapéutico , Animales , Bupivacaína/administración & dosificación , Bupivacaína/farmacocinética , Bupivacaína/uso terapéutico , Preparaciones de Acción Retardada , Modelos Animales de Enfermedad , Perros , Evaluación Preclínica de Medicamentos , Femenino , Hernia Inguinal/cirugía , Inyecciones , Liposomas , Masculino , Conejos , Distribución Aleatoria , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología
20.
Anat Rec (Hoboken) ; 294(9): 1511-24, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21809467

RESUMEN

Myristoylated alanine-rich C-kinase substrate (MARCKS) is an actin binding protein substrate of protein kinase C (PKC) and critical for mouse and Xenopus development. Herein two MARCKS paralogs, marcksa and marcksb, are identified in zebrafish and the role of these genes in zebrafish development is evaluated. Morpholino-based targeting of either MARCKS protein resulted in increased mortality and a range of gross phenotypic abnormalities. Phenotypic abnormalities were classified as mild, moderate or severe, which is characterized by a slight curve of a full-length tail, a severe curve or twist of a full-length tail and a truncated tail, respectively. All three phenotypes displayed abnormal neural architecture. Histopathology of Marcks targeted embryos revealed abnormalities in retinal layering, gill formation and skeletal muscle morphology. These results demonstrate that Marcksa and Marcksb are required for normal zebrafish development and suggest that zebrafish are a suitable model to further study MARCKS function.


Asunto(s)
Embrión no Mamífero/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Morfolinos/farmacología , Pez Cebra/crecimiento & desarrollo , Secuencia de Aminoácidos , Animales , Embrión no Mamífero/citología , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Familia de Multigenes , Sustrato de la Proteína Quinasa C Rico en Alanina Miristoilada , Fenotipo , Filogenia , Homología de Secuencia de Aminoácido , Pez Cebra/genética
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