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1.
J Biol Chem ; 299(1): 102801, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36528065

RESUMO

Protein phase separation is thought to be a primary driving force for the formation of membrane-less organelles, which control a wide range of biological functions from stress response to ribosome biogenesis. Among phase-separating (PS) proteins, many have intrinsically disordered regions (IDRs) that are needed for phase separation to occur. Accurate identification of IDRs that drive phase separation is important for testing the underlying mechanisms of phase separation, identifying biological processes that rely on phase separation, and designing sequences that modulate phase separation. To identify IDRs that drive phase separation, we first curated datasets of folded, ID, and PS ID sequences. We then used these sequence sets to examine how broadly existing amino acid property scales can be used to distinguish between the three classes of protein regions. We found that there are robust property differences between the classes and, consequently, that numerous combinations of amino acid property scales can be used to make robust predictions of protein phase separation. This result indicates that multiple, redundant mechanisms contribute to the formation of phase-separated droplets from IDRs. The top-performing scales were used to further optimize our previously developed predictor of PS IDRs, ParSe. We then modified ParSe to account for interactions between amino acids and obtained reasonable predictive power for mutations that have been designed to test the role of amino acid interactions in driving protein phase separation. Collectively, our findings provide further insight into the classification of IDRs and the elements involved in protein phase separation.


Assuntos
Proteínas Intrinsicamente Desordenadas , Proteínas Intrinsicamente Desordenadas/química , Domínios Proteicos , Aminoácidos
2.
BMC Med Educ ; 23(1): 887, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990314

RESUMO

BACKGROUND: Faculty have traditionally taught the physical examination (PE) to novice medical students (pre-clerkship students.), despite recruiting and cost issues and problems standardizing their approach. ACTIVITY: We present a model using standardized patient instructor (SPI)-fourth year medical student (MS4) teams to teach PE to pre-clerkship students, leveraging the benefits of co-teaching and peer-assisted learning. RESULTS: Surveys of pre-clerkship students, MS4s and SPIs indicate positive perceptions of the program, including MS4s reporting significant growth in their professional identities as educators. Pre-clerkship students' performance on the spring clinical skills exams was equivalent to or better than their peer performance pre-program implementation. IMPLICATIONS: SPI-MS4 teams can effectively teach novice students the mechanics and clinical context of the beginners' physical exam.


Assuntos
Estágio Clínico , Pessoal de Educação , Estudantes de Medicina , Humanos , Exame Físico , Competência Clínica , Docentes , Ensino
3.
BMC Med Educ ; 22(1): 533, 2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35804336

RESUMO

BACKGROUND: Our goal was to improve pediatric residents' advanced communication skills in the setting of referral to address the entrustable professional activity of subspecialty referral identified by the American Board of Pediatrics. To accomplish this aim, we created a referral and consultation curriculum to teach and assess core communication skills in subspecialty referral involving an adolescent with syncope, an anxiety-provoking symptom that is rarely associated with serious pathology. METHODS: We utilized blended multimodal educational interventions to improve resident communication skills in referral of patients. Trainees participated in 1) an interactive online module on syncope focusing on "red-flag" symptoms that would warrant a subspecialty cardiology referral and 2) a 4-h intervention with Standardized Parents (SPs), focusing on the case-based application of communication skills. Communication skills were assessed by two pre- and post- Objective Structured Clinical Examination encounters of patients with syncope, with an SP evaluation using a 20-item checklist. Analysis was performed with Sign test and McNemar's test. Trainees provided feedback on a Critical Incident Questionnaire, which was analyzed qualitatively. RESULTS: Sixty-four residents participated. There was an overall improvement in communication skills based on SP scores (82.7 ± 10.9% to 91.7 ± 5.0%, p < 0.001), and 13/20 items demonstrated significant improvement post-intervention. Residents' improved performance enabled them to address patient/family emotions, explain referral logistics, and clarify concerns to agree on a plan. CONCLUSIONS: By participating in this curriculum, residents' communication skills improved immediately post-intervention. Further research is needed to assess if this intervention improves patient care by providing residents with enduring skills to judiciously manage the referral process.


Assuntos
Internato e Residência , Adolescente , Criança , Competência Clínica , Comunicação , Currículo , Humanos , Encaminhamento e Consulta , Síncope
4.
RNA Biol ; 18(2): 178-193, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-31752575

RESUMO

The La-related proteins (LaRPs) are an ancient superfamily of RNA-binding proteins orchestrating the major fates of RNA, from processing and maturation to regulation of mRNA translation. LaRPs are instrumental in modulating complex assemblies where the RNA is bound, folded, processed, escorted and presented to the functional effectors often through recruitment of protein partners. This intricate web of protein-RNA and protein-protein interactions is enabled by the modular nature of the LaRPs, comprising several structured domains connected by flexible linkers, and other sequences lacking recognizable folded motifs. Recent structures, together with biochemical and biophysical studies, have provided insights into how each LaRP family has evolved unique mechanisms of RNA recognition, not only through the conserved RNA-binding unit, the La-module, but also mediated by other family-specific motifs. Furthermore, in a series of unexpected twists and turns, they have revealed that the dynamic and conformational interplay of multi-structured domains and disordered regions operate in unison to achieve RNA substrate discrimination. This review proposes a perspective of our current knowledge of the structure-function relationship of the LaRP superfamily.


Assuntos
Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas/química , Ribonucleoproteínas/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Humanos , Família Multigênica , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , RNA/química , RNA/metabolismo , Clivagem do RNA , Proteínas de Ligação a RNA/genética , Ribonucleoproteínas/genética , Ribonucleosídeo Difosfato Redutase/química , Ribonucleosídeo Difosfato Redutase/metabolismo , Relação Estrutura-Atividade , Especificidade por Substrato
5.
Molecules ; 26(3)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530506

RESUMO

The α and polyproline II (PPII) basins are the two most populated regions of the Ramachandran map when constructed from the protein coil library, a widely used denatured state model built from the segments of irregular structure found in the Protein Data Bank. This indicates the α and PPII conformations are dominant components of the ensembles of denatured structures that exist in solution for biological proteins, an observation supported in part by structural studies of short, and thus unfolded, peptides. Although intrinsic conformational propensities have been determined experimentally for the common amino acids in short peptides, and estimated from surveys of the protein coil library, the ability of these intrinsic conformational propensities to quantitatively reproduce structural behavior in intrinsically disordered proteins (IDPs), an increasingly important class of proteins in cell function, has thus far proven elusive to establish. Recently, we demonstrated that the sequence dependence of the mean hydrodynamic size of IDPs in water and the impact of heat on the coil dimensions, provide access to both the sequence dependence and thermodynamic energies that are associated with biases for the α and PPII backbone conformations. Here, we compare results from peptide-based studies of intrinsic conformational propensities and surveys of the protein coil library to those of the sequence-based analysis of heat effects on IDP hydrodynamic size, showing that a common structural and thermodynamic description of the protein denatured state is obtained.


Assuntos
Proteínas Intrinsicamente Desordenadas/química , Peptídeos/química , Sequência de Aminoácidos , Proteínas Intrinsicamente Desordenadas/genética , Modelos Moleculares , Peptídeos/genética , Conformação Proteica , Desnaturação Proteica , Termodinâmica , Água/química
6.
Protein Expr Purif ; 134: 147-153, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28400296

RESUMO

The RNA-binding proteins that comprise the La-related protein (LARP) superfamily have been implicated in a wide range of cellular functions, from tRNA maturation to regulation of protein synthesis. To more expansively characterize the biological function of the LARP6 subfamily, we have recombinantly expressed the full-length LARP6 proteins from two teleost fish, platyfish (Xiphophorus maculatus) and zebrafish (Danio rerio). The yields of the recombinant proteins were enhanced to >2 mg/L using a tandem approach of an N-terminal His6-SUMO tag and an iterative solubility screening assay to identify structurally stabilizing buffer components. The domain topologies of the purified fish proteins were probed with limited proteolysis. The fish proteins contain an internal, protease-resistant 40 kDa domain, which is considerably more stable than the comparable domain from the human LARP6 protein. The fish proteins are therefore a lucrative model system in which to study both the evolutionary divergence of this family of La-related proteins and the structure and conformational dynamics of the domains that comprise the LARP6 protein.


Assuntos
Ciprinodontiformes/genética , Expressão Gênica , Proteínas de Ligação a RNA , Proteínas de Peixe-Zebra , Peixe-Zebra/genética , Animais , Ciprinodontiformes/metabolismo , Humanos , Domínios Proteicos , Proteínas de Ligação a RNA/biossíntese , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/biossíntese , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/isolamento & purificação
7.
Anal Biochem ; 511: 36-41, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27495142

RESUMO

Interactions between proteins and nucleic acids are frequently analyzed using electrophoretic mobility shift assays (EMSAs). This technique separates bound protein:nucleic acid complexes from free nucleic acids by electrophoresis, most commonly using polyacrylamide gels. The current study utilizes recent advances in agarose gel electrophoresis technology to develop a new EMSA protocol that is simpler and faster than traditional polyacrylamide methods. Agarose gels are normally run at low voltages (∼10 V/cm) to minimize heating and gel artifacts. In this study we demonstrate that EMSAs performed using agarose gels can be run at high voltages (≥20 V/cm) with 0.5 × TB (Tris-borate) buffer, allowing for short run times while simultaneously yielding high band resolution. Several parameters affecting band and image quality were optimized for the procedure, including gel thickness, agarose percentage, and applied voltage. Association of the siRNA-binding protein p19 with its target RNA was investigated using the new system. The agarose gel and conventional polyacrylamide gel methods generated similar apparent binding constants in side-by-side experiments. A particular advantage of the new approach described here is that the short run times (5-10 min) reduce opportunities for dissociation of bound complexes, an important concern in non-equilibrium nucleic acid binding experiments.


Assuntos
Ensaio de Desvio de Mobilidade Eletroforética/métodos , Proteínas de Ligação a RNA/química , RNA/química , Eletroforese em Gel de Ágar/métodos , RNA/metabolismo , Proteínas de Ligação a RNA/metabolismo
8.
Nucleic Acids Res ; 42(1): 475-84, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24057216

RESUMO

Cdc13, the telomere end-binding protein from Saccharomyces cerevisiae, is a multidomain protein that specifically binds telomeric single-stranded DNA (ssDNA) with exquisitely high affinity to coordinate telomere maintenance. Recent structural and genetic data have led to the proposal that Cdc13 is the paralog of RPA70 within a telomere-specific RPA complex. Our understanding of Cdc13 structure and biochemistry has been largely restricted to studies of individual domains, precluding analysis of how each domain influences the activity of the others. To better facilitate a comparison to RPA70, we evaluated the ssDNA binding of full-length S. cerevisiae Cdc13 to its minimal substrate, Tel11. We found that, unlike RPA70 and the other known telomere end-binding proteins, the core Cdc13 ssDNA-binding activity is wholly contained within a single tight-binding oligosaccharide/oligonucleotide/oligopeptide binding (OB)-fold. Because two OB-folds are implicated in dimerization, we also evaluated the relationship between dimerization and ssDNA-binding activity and found that the two activities are independent. We also find that Cdc13 binding exhibits positive cooperativity that is independent of dimerization. This study reveals that, while Cdc13 and RPA70 share similar domain topologies, the corresponding domains have evolved different and specialized functions.


Assuntos
DNA de Cadeia Simples/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Ligação a Telômeros/metabolismo , Telômero/metabolismo , Ligação Proteica , Multimerização Proteica , Estrutura Terciária de Proteína , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Ligação a Telômeros/química
9.
Teach Learn Med ; 28(4): 395-405, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27152446

RESUMO

Construct: Traditionally, standardized patients (SPs) assess students' clinical skills principally through numerical rating forms-an approach that may not fully capture SPs' concerns. SPs are students' closest approximation to real patients. To maximally benefit students' clinical training and evaluation it is important to find ways to give voice to the totality of SPs' perspectives. BACKGROUND: SPs have been shown to be a reliable and valid means to assess medical students' clinical skills in clinical skills examinations. We noticed, however, that SPs often express "off the record" concerns about students, which they do not include on traditional assessment forms. APPROACH: To explore these "off the record" concerns, we designed a Concerns item and added it to the traditional assessment form for an end-of-3rd-year clinical skills examination shared by three medical schools. We asked SPs to use this Concerns item to identify students about whom they had any "gut-level" concerns and provided them with a narrative opportunity to explain why. SPs were informed that the purpose of the item was to help students with difficulties and was not part of the student's grade. RESULTS: We analyzed the concerns data using quantitative and qualitative methods. Of 551 students at three schools, 223 (∼40%) had concerns recorded. Seventy students received two or more concerns. Qualitative analysis of SPs' comments revealed 3 major categories of concern: communication and interpersonal skills, history taking, and physical exam. Grouped under each were several subcategories. More than half of the written comments from the SPs related to the communication/interpersonal skills category and included subcategories commonly addressed in communications courses: lack of empathy, good listening skills, and lack of connection to the patient. They also included subcategories that in our experience are less commonly addressed: odd or off-putting mannerisms, lack of confidence, unprofessional behavior, domineering behavior, and biased behavior. Another 47% of concerns identified deficiencies in history taking and physical examination. Of the students with concerns noted by two or more SPs, SPs' narrative comments on 84%, 42%, and 48% of the students in the domains of communications, history, and physical exam respectively indicated potential problems not identified by scores on the traditional assessment form. CONCLUSION: The Concerns item is a narrative assessment method that may add value to traditional quantitative scoring by identifying and characterizing problematic student performance not captured by the traditional assessment form. It may thus contribute to giving fuller voice to the totality of SPs' perspective.


Assuntos
Competência Clínica , Comunicação , Estudantes de Medicina , Empatia , Humanos , Simulação de Paciente , Relações Médico-Paciente
10.
J Genet Couns ; 23(4): 522-30, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24306140

RESUMO

There is tremendous excitement about the promise of new genomic technologies to transform medical practice and improve patient care. Although the full power of genetic diagnosis has not yet been realized, paradigms of clinical decision-making are changing. In fact, recent policy level changes to promote genetic counseling by certified genetics professionals (GP) such as genetic counselors and clinical geneticists, are occurring at both the payer and state level. However, there remain opportunities to develop policies within the United States to: 1) enhance the access to the limited workforce of GPs; 2) revise reimbursement schemes such that costs to deliver these services may be recouped by institutions with GPs; and 3) protect against the potential for discrimination based on genetic information. Although many of these issues predate advances in genomic technologies, they are exacerbated by them, with increasing access and awareness as costs of testing decrease. Consequently, evolving shifts in national policies poise GPs to serve as a hub of information and may be instrumental in facilitating new models to deliver genetics-based care through promoting academic-community partnerships and interfacing with non-GPs. As we acknowledge the potential for genomics to revolutionize medical practice, the expertise of GPs may be leveraged to facilitate incorporation of this information into mainstream medicine.


Assuntos
Aconselhamento Genético , Predisposição Genética para Doença , Neoplasias/genética , Papel Profissional , Humanos , Medição de Risco
11.
Res Sq ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38496572

RESUMO

Titin is the largest protein produced by living cells and its function as a molecular spring in striated muscle is well characterized (1, 2). Here we demonstrate that titin isoforms in the same size range as found in muscle are prominent neuronal proteins in both the central and peripheral nervous systems, including motor neurons in the spinal cord and brain. Within these neurons, titin localizes to the dense fibrillar component of the nucleolus, the site of ribosomal RNA biogenesis and modification, and a critical site of dysfunction in neurodegenerative disease (3-5). Additionally, we show that the levels of both titin mRNA and protein are altered in the spinal cord of SOD1G93A mice, a commonly used model of amyotrophic lateral sclerosis, indicating that titin mediated nucleolar events may in fact contribute to the pathobiology of disease.

12.
Protein Sci ; 32(9): e4756, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37574757

RESUMO

We have developed an algorithm, ParSe, which accurately identifies from the primary sequence those protein regions likely to exhibit physiological phase separation behavior. Originally, ParSe was designed to test the hypothesis that, for flexible proteins, phase separation potential is correlated to hydrodynamic size. While our results were consistent with that idea, we also found that many different descriptors could successfully differentiate between three classes of protein regions: folded, intrinsically disordered, and phase-separating intrinsically disordered. Consequently, numerous combinations of amino acid property scales can be used to make robust predictions of protein phase separation. Built from that finding, ParSe 2.0 uses an optimal set of property scales to predict domain-level organization and compute a sequence-based prediction of phase separation potential. The algorithm is fast enough to scan the whole of the human proteome in minutes on a single computer and is equally or more accurate than other published predictors in identifying proteins and regions within proteins that drive phase separation. Here, we describe a web application for ParSe 2.0 that may be accessed through a browser by visiting https://stevewhitten.github.io/Parse_v2_FASTA to quickly identify phase-separating proteins within large sequence sets, or by visiting https://stevewhitten.github.io/Parse_v2_web to evaluate individual protein sequences.


Assuntos
Transição de Fase , Proteínas , Software , Algoritmos , Proteínas/química , Proteoma
13.
Ethn Dis ; 33(4): 163-169, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38854412

RESUMO

Objectives: Black youth are disproportionately affected by the US obesity epidemic. Early-age obesity often continues into adulthood and is associated with a higher risk of diabetes, cardiovascular disease, and premature death. Few studies have incorporated community-based participatory research (CBPR) facilitated by youth to provide frank discussions among teens living in inner cities about challenges and facilitators in maintaining a healthy weight and to design teen-identified interventions. Design: Black youth (n=10) were recruited from a Baltimore City high school during the 2019 to 2020 academic year and were trained by seasoned investigators and mentored by graduate and undergraduate students on qualitative methods using CBPR. These youth then implemented focus groups with their peers aged 15 to 18 years (10 focus groups of 10 teens each). Topics included healthy lifestyle knowledge, behaviors, attitudes, and suggested interventions. Content analyses were conducted using dual-rater techniques. Results: Focus group themes yielded strengths and challenges of weight maintenance for Black youth at various levels, including in their personal lives, families, school, and community. Themes also suggested several technology-based possibilities using social media to reach Black youth about healthy living practices. Conclusions: Engagement of Black youth in CBPR projects can yield valuable data to design more culturally responsive and developmentally appropriate interventions. Youth are competent collectors of information to identify needed changes in their schools/communities and about the use of technology/social media to facilitate improved health practices among their peers and should be involved early in the process of developing targeted obesity prevention interventions and/or programs.


Assuntos
Negro ou Afro-Americano , Pesquisa Participativa Baseada na Comunidade , Grupos Focais , Estilo de Vida Saudável , Grupo Associado , Humanos , Adolescente , Baltimore , Negro ou Afro-Americano/psicologia , Feminino , Masculino , Conhecimentos, Atitudes e Prática em Saúde/etnologia
14.
J Biol Chem ; 285(21): 16239-47, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20228065

RESUMO

Transforming growth factor beta (TGF-beta) stimulates reactive oxygen species (ROS) production in various cell types, which mediates many of the effects of TGF-beta. The molecular mechanisms whereby TGF-beta increases ROS production and ROS modulate the signaling processes of TGF-beta, however, remain poorly defined. In this study, we show that TGF-beta1 stimulates NADPH oxidase 4 (Nox4) expression and ROS generation in the nucleus of murine embryo fibroblasts (NIH3T3 cells). This is associated with an increase in protein thiol modification and inactivation of MAPK phosphatase 1 (MKP-1), a nuclear phosphatase. Furthermore, knockdown of MKP-1 using small interfering RNA enhances TGF-beta1-induced phosphorylation of JNK and p38 as well as the expression of plasminogen activator inhibitor 1 (PAI-1), a TGF-beta-responsive gene involved in the pathogenesis of many diseases. Knockdown of Nox4 with Nox4 small interfering RNA, on the other hand, reduces TGF-beta1-stimulated ROS production, p38 phosphorylation, and PAI-1 expression. TGF-beta also increased the nuclear level of Nox4 protein as well as PAI-1 expression in human lung fibroblasts (CCL-210 cells), suggesting that TGF-beta may induce PAI-1 expression by a similar mechanism in human lung fibroblasts. In summary, in this study we have identified nuclear MAPK phosphatase MKP-1 as a novel molecular target of ROS in TGF-beta signaling pathways. Our data suggest that increased generation of ROS by Nox4 mediates TGF-beta1-induced PAI-1 gene expression at least in part through oxidative modification and inhibition of MKP-1 leading to a sustained activation of JNK and p38 MAPKs.


Assuntos
Fosfatase 1 de Especificidade Dupla/metabolismo , Fibroblastos/metabolismo , Regulação da Expressão Gênica/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Nucleares/metabolismo , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Fator de Crescimento Transformador beta1/metabolismo , Animais , Fosfatase 1 de Especificidade Dupla/genética , Fibroblastos/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , NADPH Oxidase 4 , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Células NIH 3T3 , Proteínas Nucleares/genética , Oxirredução/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Inibidor 1 de Ativador de Plasminogênio/genética , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Am J Pathol ; 177(6): 3037-50, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21056999

RESUMO

The pathological hallmark of Parkinson's disease and diffuse Lewy body disease (DLBD) is the aggregation of α-synuclein (α-syn) in the form of Lewy bodies and Lewy neurites. Patients with both Alzheimer's disease (AD) and cortical Lewy pathology represent the Lewy body variant of AD (LBV) and constitute 25% of AD cases. C-terminally truncated forms of α-syn enhance the aggregation of α-syn in vitro. To investigate the presence of C-terminally truncated α-syn in DLBD, AD, and LBV, we generated and validated polyclonal antibodies to truncated α-syn ending at residues 110 (α-syn110) and 119 (α-syn119), two products of 20S proteosome-mediated endoproteolytic cleavage. Double immunofluorescence staining of the cingulate cortex showed that α-syn110 and α-syn140 (full-length) aggregates were not colocalized in LBV. All aggregates containing α-syn140 also contained α-syn119; however, some aggregates contained α-syn119 without α-syn140, suggesting that α-syn119 may stimulate aggregate formation. Immunohistochemistry and image analysis of tissue microarrays of the cingulate cortex from patients with DLBD (n = 27), LBV (n = 27), and AD (n = 19) and age-matched controls (n = 15) revealed that AD is also characterized by frequent abnormal neurites containing α-syn119. Notably, these neurites did not contain α-syn ending at residues 110 or 122-140. The presence of abnormal neurites containing α-syn119 in AD without conventional Lewy pathology suggests that AD and Lewy body disease may be more closely related than previously thought.


Assuntos
Doença de Alzheimer/metabolismo , Corpos de Lewy/patologia , Neuritos/metabolismo , Neuritos/patologia , alfa-Sinucleína/metabolismo , Idoso , Doença de Alzheimer/patologia , Autopsia , Encéfalo/metabolismo , Encéfalo/patologia , Estudos de Casos e Controles , Humanos , Imuno-Histoquímica , Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/patologia , Pessoa de Meia-Idade , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Estrutura Terciária de Proteína , Análise Serial de Tecidos , alfa-Sinucleína/química
16.
Simul Healthc ; 16(1): 3-12, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32467515

RESUMO

INTRODUCTION: Little is known about the nature of standardized patient (SP) identity and its formation. Understanding identity and formation can have important implications for recruiting, working with, and retaining SPs. Social relational theory explains how identity is formed in a social context in relationship with others. In keeping with social relational theory, this study explored SP identity formation through the SP experience with one of the most important elements of their social context-medical students. METHODS: Using qualitative methods, we conducted four 1-hour semistructured focus group interviews with SPs (N = 18). Interviews were audio recorded and transcribed verbatim. We used a constant comparative approach and consensus development to analyze the data and identify codes, categories, and ultimately themes. We used multiple methods to ensure credibility and trustworthiness of the study, as well as transparency of methods and thick rich descriptions to enable readers to judge transferability of the findings and conclusions. RESULTS: We identified 4 major themes. Through their interactions, SPs experienced: (1) identity transformation toward a new professional identity; (2) self-actualization toward their maximum potential; (3) judgmental reactions to medical student behaviors; and (4) simulation-reality interaction between their simulated and real selves. CONCLUSIONS: Through their interactions with medical students, SPs experienced a transformation into a complex identity composed of multiple roles. Within this identity, they found purpose, fulfillment, and self-actualization through fostering students', as well as their own, personal, and professional growth and through developing a higher sense of social responsibility. Within this identity, they also encountered the challenges of navigating between judging and supporting medical students, and toggling between their real and simulated selves. Guided by the SPs' perspectives, and in conjunction with professional organizational standards, we provide recommendations for training, recruitment, and retention of SPs.


Assuntos
Estudantes de Medicina , Grupos Focais , Humanos , Identificação Social
17.
Animals (Basel) ; 11(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34573532

RESUMO

Ensuring good health and welfare is an increasingly important consideration for conservation of endangered species, whether free-ranging or managed to varying degrees under human care. The welfare-based design of a new habitat for Asian elephants at the Oregon Zoo focused on meeting the elephants' physical, physiological, psychological, and social needs 24 h a day and across life stages. The habitat was designed to encourage activity, promote species-typical behaviors, support changing social dynamics, offer increased opportunities for choice, and provide biologically meaningful challenges. In this 4-year study, we monitored elephant health and welfare indicators throughout the transition and acclimation from the previous habitat to the new habitat. Several welfare indicators obtained through longitudinal hormone analyses, behavior assessments, and GPS measurement of walking distance and space use provided evidence that these goals were achieved. The elephants were more active and walked farther on a daily basis in the new habitat, with an average walking distance of over 15 km per day. A switch from primarily caretaker-delivered food to seeking food on their own indicates that the disbursement of food with less temporal and spatial predictability increased foraging opportunities, which better satisfies appetitive motivations important for psychological well-being. All individuals showed adaptive and normal adrenal responses to change and challenge, with the highest fecal glucocorticoid metabolite (FGM) concentrations and variability during the construction phase, and a return to previous baseline concentrations in the new habitat, suggesting they acclimated well to the new environment. The elephants expressed a diverse range of species-typical behaviors and demonstrated social dynamics of a healthy herd in both habitats with transitions of individuals through life stages. They exhibited more autonomy in choosing whom to associate with socially and also by choosing different aspects of their environment with regular indoor/outdoor access and extensive resource use in the new habitat. Findings indicate that the complexity and flexibility of the new habitat and habitat management has been effective in improving overall welfare by providing meaningful challenges and the opportunity to express appetitive behaviors, by offering choice in environmental conditions, and by providing the space and resource distribution to support evolving herd dynamics and increased social equity for individuals.

18.
J Bioenerg Biomembr ; 42(1): 85-95, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20148295

RESUMO

A hallmark of Parkinson disease (PD) is the formation of intracellular protein inclusions called Lewy bodies that also contain mitochondria. alpha-Synuclein (alpha Syn) is a major protein component of Lewy bodies, where it is in an amyloid conformation and a significant fraction is truncated by poorly understood proteolytic events. Previously, we demonstrated that the 20S proteasome cleaves alpha Syn in vitro to produce fragments like those observed in Lewy bodies and that the fragments accelerate the formation of amyloid fibrils from full-length alpha Syn. Three point mutations in alpha Syn are associated with early-onset familial PD: A30P, E46K, and A53T. However, these mutations have very different effects on the amyloidogenicity and vesicle-binding activity of alpha Syn, suggesting neither of these processes directly correlate with neurodegeneration. Here, we evaluate the effect of the disease-associated mutations on the fragmentation, conformation, and association reactions of alpha Syn in the presence of the 20S proteasome and liposomes. The 20S proteasome produced the C-terminal fragments from both the mutant and wildtype alpha Syn. These truncations accelerated fibrillization of all alpha-synucleins, but again there was no clear correlation between the PD-associated mutations and amyloid formation in the presence of liposomes. Recent data suggests that cellular toxicity is caused by a soluble oligomeric species, which is a precursor to the amyloid form and is immunologically distinguishable from both soluble monomeric and amyloid forms of alpha Syn. Notably, the rate of formation of the soluble, presumptively cytotoxic oligomers correlated with the disease-associated mutations when both 20S proteasome and liposomes were present. Under these conditions, the wildtype protein was also cleaved and formed the oligomeric structures, albeit at a slower rate, suggesting that 20S-mediated truncation of alpha Syn may play a role in sporadic PD as well. Evaluation of the biochemical reactions of the PD-associated alpha-synuclein mutants in our in vitro system provides insight into the possible pathogenetic mechanism of both familial and sporadic PD.


Assuntos
Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Mutação Puntual , Complexo de Endopeptidases do Proteassoma/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Amiloide/biossíntese , Animais , Bovinos , Humanos , Técnicas In Vitro , Cinética , Corpos de Lewy/genética , Corpos de Lewy/metabolismo , Lipossomos , Modelos Neurológicos , Doença de Parkinson/etiologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Multimerização Proteica , alfa-Sinucleína/química
19.
Zoo Biol ; 29(2): 221-36, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20014111

RESUMO

The foot health of elephants in human care is a longstanding concern. In 2001, the AZA Standards for Elephant Management and Care were published recommending husbandry to improve foot health. This article reports the results of a 2006 survey: basic statistics describing facility, husbandry, and foot health attributes are reported and relationships among variables are investigated. Median area available to elephants exceeded Standard recommendations (755 ft(2) per elephant indoor and 10,000 ft(2) outdoor). Concrete makes up 69% of indoor area and natural substrates account for 85% of outdzoor area. Elephants in AZA facilities received an average of 45.5 min/day of exercise, and facilities with a structured exercise plan provided significantly more exercise than did facilities without a structured exercise plan (z=-2.522, P=0.012). Enrichment is important to psychological health and may also stimulate activity beneficial to foot health; 95% of institutions had a structured enrichment program. Preventative foot care was nearly universal, and 100% of facilities performed routine nail and pad trimming. However, foot pathology has not been eradicated; 33% of institutions reported at least one pathology in the previous year. This study found a strong inverse relationship between foot pathology and exercise (chi(2)(3)=24.34, P<0.001). Younger herds were less likely to have a member diagnosed with arthritis (chi(2)(1)=8.90, P=0.003). Lameness was unrelated to age or pathology, and only the presence of arthritis explained lameness (z=-7.81, P<0.001). African elephants seemed to experience lower rates of foot pathology and arthritis than Asian elephants; however, this was explained by differences in age.


Assuntos
Criação de Animais Domésticos/normas , Animais de Zoológico , Elefantes , Doenças do Pé/veterinária , Animais , Artrite/diagnóstico , Artrite/veterinária , Feminino , Doenças do Pé/epidemiologia , Abrigo para Animais , Coxeadura Animal , Masculino , América do Norte/epidemiologia , Estudos Retrospectivos
20.
J Dent Hyg ; 94(1): 39-48, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32127428

RESUMO

Purpose: An aging population, combined with increasing tooth retention, could significantly impact the dental care delivery system. The purpose of this study was to assess self-reported oral health and the factors associated with oral health outcomes among a random sample of older adults in Washington State.Methods: A telephone survey of adults 55+ years was used to collect information on factors associated with oral health, plus four outcome variables; substantial tooth loss (6+ teeth lost), oral problems, oral pain, and poor health of teeth. Data were weighted to reflect the state's age and gender statistics.Results: A total of 2,988 older adults completed the survey during 2017. Substantial tooth loss (18%), oral problems (17%) and oral pain (13%) were the most frequently reported issues. Of the adults with teeth, 17% reported fair/poor health of teeth. Compared to adults with an income of $75,000 or more, adults with an income less than $25,000 were twice as likely to have substantial tooth loss and oral problems (OR=2.1 and 2.2, respectively) and were three times more likely to report oral pain and poor health of teeth (OR=3.1 and 3.3, respectively). The oldest old (adults 75+ years), as compared to those 55-64 years, were significantly more likely to have substantial tooth loss (OR=2.6) but were less likely to report oral problems (OR=0.6), pain (OR=0.3), or poor health of teeth (OR=0.5).Conclusions: Although the majority of Washington's older adults report having good oral health, a small subgroup has oral problems which may have a negative impact on quality of life.


Assuntos
Saúde Bucal , Perda de Dente , Idoso , Idoso de 80 Anos ou mais , Humanos , Qualidade de Vida , Inquéritos e Questionários , Washington
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