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1.
Nucleic Acids Res ; 45(20): 11941-11953, 2017 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-28981728

RESUMEN

In the human genome, translation initiation from non-AUG codons plays an important role in various gene regulation programs. However, mechanisms regulating the non-AUG initiation rate remain poorly understood. Here, we show that the non-AUG initiation rate is nearly consistent under a fixed nucleotide context in various human and insect cells. Yet, it ranges from <1% to nearly 100% compared to AUG translation, depending on surrounding sequences, including Kozak, and possibly additional nucleotide contexts. Mechanistically, this range of non-AUG initiation is controlled in part, by the eIF5-mimic protein (5MP). 5MP represses non-AUG translation by competing with eIF5 for the Met-tRNAi-binding factor eIF2. Consistently, eIF5 increases, whereas 5MP decreases translation of NAT1/EIF4G2/DAP5, whose sole start codon is GUG. By modulating eIF5 and 5MP1 expression in combination with ribosome profiling we identified a handful of previously unknown non-AUG initiation sites, some of which serve as the exclusive start codons. If the initiation rate for these codons is low, then an AUG-initiated downstream ORF prevents the generation of shorter, AUG-initiated isoforms. We propose that the homeostasis of the non-AUG translatome is maintained through balanced expression of eIF5 and 5MP.


Asunto(s)
Codón Iniciador/genética , Proteínas de Unión al ADN/genética , Factor 5 Eucariótico de Iniciación/genética , Genoma Humano , Animales , Unión Competitiva , Línea Celular , Línea Celular Tumoral , Codón Iniciador/metabolismo , Proteínas de Unión al ADN/metabolismo , Factor 2 Eucariótico de Iniciación/genética , Factor 2 Eucariótico de Iniciación/metabolismo , Factor 5 Eucariótico de Iniciación/metabolismo , Regulación de la Expresión Génica , Células HEK293 , Homeostasis/genética , Humanos , Unión Proteica , Biosíntesis de Proteínas/genética , Ribosomas/genética , Ribosomas/metabolismo
2.
Transpl Infect Dis ; 20(2): e12866, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29512234

RESUMEN

BACKGROUND: Conjugated pneumococcal vaccine is recommended for kidney transplant recipients, however, their immunogenicity and potential to trigger allograft rejection though generation of de novo anti-human leukocyte antigen antibodies has not been well studied. METHODS: Clinically stable kidney transplant recipients participated in a prospective cohort study and received a single dose of 13-valent conjugate pneumococcal vaccine. Anti-pneumococcal IgG was measured for the 13 vaccine serotypes pre and post vaccination and functional anti-pneumococcal IgG for 4 serotypes post vaccination. Anti-human leukocyte antigen antibodies antibodies were measured before and after vaccination. Kidney transplant recipients were followed clinically for 12 months for episodes of allograft rejection or invasive pneumococcal disease. RESULTS: Forty-five kidney transplant recipients participated. Median days between pre and post vaccination serology was 27 (range 21-59). Post vaccination, there was a median 1.1 to 1.7-fold increase in anti-pneumococcal IgG antibody concentrations for all 13 serotypes. Kidney transplant recipients displayed a functional antibody titer ≥1:8 for a median of 3 of the 4 serotypes. Post vaccination, there were no de novo anti-human leukocyte antigen antibodies, no episodes of biopsy proven rejection or invasive pneumococcal disease. CONCLUSION: A single dose of 13-valent conjugate pneumococcal vaccine elicits increased titers and breadth of functional anti-pneumococcal antibodies in kidney transplant recipients without stimulating rejection or donor-specific antibodies.


Asunto(s)
Trasplante de Riñón , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/efectos adversos , Vacunas Neumococicas/farmacología , Anticuerpos Antibacterianos/sangre , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Vacunación
3.
Nucleic Acids Res ; 44(18): 8704-8713, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27325740

RESUMEN

ATF4 is a pro-oncogenic transcription factor whose translation is activated by eIF2 phosphorylation through delayed re-initiation involving two uORFs in the mRNA leader. However, in yeast, the effect of eIF2 phosphorylation can be mimicked by eIF5 overexpression, which turns eIF5 into translational inhibitor, thereby promoting translation of GCN4, the yeast ATF4 equivalent. Furthermore, regulatory protein termed eIF5-mimic protein (5MP) can bind eIF2 and inhibit general translation. Here, we show that 5MP1 overexpression in human cells leads to strong formation of 5MP1:eIF2 complex, nearly comparable to that of eIF5:eIF2 complex produced by eIF5 overexpression. Overexpression of eIF5, 5MP1 and 5MP2, the second human paralog, promotes ATF4 expression in certain types of human cells including fibrosarcoma. 5MP overexpression also induces ATF4 expression in Drosophila The knockdown of 5MP1 in fibrosarcoma attenuates ATF4 expression and its tumor formation on nude mice. Since 5MP2 is overproduced in salivary mucoepidermoid carcinoma, we propose that overexpression of eIF5 and 5MP induces translation of ATF4 and potentially other genes with uORFs in their mRNA leaders through delayed re-initiation, thereby enhancing the survival of normal and cancer cells under stress conditions.


Asunto(s)
Factor de Transcripción Activador 4/metabolismo , Proteínas de Unión al ADN/metabolismo , Factor 2 Eucariótico de Iniciación/metabolismo , Factor 5 Eucariótico de Iniciación/metabolismo , Iniciación de la Cadena Peptídica Traduccional , Animales , Carcinogénesis/patología , Línea Celular Tumoral , Drosophila melanogaster/metabolismo , Factor 3 de Iniciación Eucariótica , Fibrosarcoma/patología , Técnicas de Silenciamiento del Gen , Células HEK293 , Células HeLa , Humanos , Masculino , Espectrometría de Masas , Ratones Desnudos
4.
J Res Adolesc ; 27(3): 492-505, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28776845

RESUMEN

This study builds on research on the power of counter-stereotypical cues, as well as intergroup contact theory, to consider whether interactions with a female teacher and female peers in a high school engineering classroom decrease male students' gender/science, technology, engineering, and math stereotypical beliefs and whether this varies according to the initial strength of their stereotypical views. Analyses reveal that among male students who initially reject stereotypes of male superiority, more female peers in the classroom leads to a further decrease in their stereotypical views by the end of the year. In contrast, boys who held strong stereotypical beliefs became less stereotypical by the end of the course when they had a female teacher. Implications for future research and current educational reforms are discussed.


Asunto(s)
Selección de Profesión , Ingeniería/educación , Maestros , Estereotipo , Adolescente , Curriculum , Femenino , Humanos , Masculino , Matemática/educación , Análisis Multivariante , Grupo Paritario , Ciencia/educación , Factores Sexuales , Tecnología/educación
5.
Reprod Health Matters ; 22(44): 174-84, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25555774

RESUMEN

The global HIV policy arena has seen a surge of interest in gender-related dimensions of vulnerability to HIV and violence. UNAIDS and other prominent actors have named gender-based violence a key priority, and there seems to be genuine understanding and commitment to addressing gender inequalities as they impact key populations in the AIDS response. In the quest for evidence-informed interventions, there is usually a strong connection between the research conducted and the policies and programmes that follow. Regarding gender, HIV and violence, is this the case? This discussion paper asks whether the relevant peer-reviewed literature is suitably representative of all affected populations--including heterosexual men, transgender men and women, women who have sex with women, and men who have sex with men--as well as whether the literature sufficiently considers gender norms and dynamics in how research is framed. Conclusions about violence in the context of heterosexual relationships, and with specific attention to heterosexual women, should not be presented as insights about gender-based violence more generally, with little attention to gender dynamics. Research framed by a more comprehensive understanding of what is meant by gender-based violence as it relates to all of the diverse populations affected by HIV would potentially guide policies and programmes more effectively.


Asunto(s)
Infecciones por VIH/psicología , Política de Salud , Sexualidad/psicología , Violencia/psicología , Femenino , Infecciones por VIH/transmisión , Humanos , Relaciones Interpersonales , Masculino , Revisión por Pares , Investigación , Conducta Sexual/psicología
6.
Psychol Rep ; 112(1): 14-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23654023

RESUMEN

Estimates of per capita centenarians in a Utah population varied between one per 12,864 and one per 4,675, depending on the data that were used, the population assumptions that were made, and the boundary limits that were employed. In general, caution is warranted in claims about the existence of longevity hotspots.


Asunto(s)
Censos , Longevidad/fisiología , Distribución por Edad , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Análisis de Supervivencia , Utah/epidemiología , Utah/etnología
7.
Cureus ; 13(12): e20847, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35141093

RESUMEN

INTRODUCTION: Co-sleeping with infants is a common practice across cultures, but pediatricians may struggle to engage in patient-centered conversations about infant sleep practices with non-native English- speaking families. Cultural humility is a critical skill to utilize when engaging in cross-cultural conversations. We designed a simulation for pediatric residents to counsel on safe sleep and enhance skills in self-perceived cultural humility and preparedness when caring for diverse patient populations. METHODS: We created a simulation for the second year and senior pediatric residents at a large academic institution focused on a co-sleeping parent and infant from the Burmese community. The Multidimensional Cultural Humility Scale (MCHS) was administered prior to and after the simulation. We also included additional questions regarding changes in knowledge and preparation in engaging in co-sleeping conversations across cultures. RESULTS: Fifty-seven residents participated. Overall, the mean score of the MCHS significantly increased after the simulation, indicating an increase in self-perceived cultural humility. All participants felt more prepared to have conversations about co-sleeping and to engage in difficult conversations with diverse patient populations, and all learned valuable skills to improve care for future patients. Comments regarding the scenario noted an appreciation for learning more about the Burmese population and understanding new approaches to safe sleep counseling. DISCUSSION: After this simulated scenario, residents reported increased self-perceived cultural humility, preparedness in counseling on co-sleeping, and skills to engage in difficult conversations with diverse patient populations. Topics such as cultural humility can be incorporated into simulation-based medical education to help improve the care of diverse patient populations.

8.
Cell Rep ; 36(2): 109376, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34260931

RESUMEN

eIF5-mimic protein (5MP) is a translational regulatory protein that binds the small ribosomal subunit and modulates its activity. 5MP is proposed to reprogram non-AUG translation rates for oncogenes in cancer, but its role in controlling non-AUG initiated synthesis of deleterious repeat-peptide products, such as FMRpolyG observed in fragile-X-associated tremor ataxia syndrome (FXTAS), is unknown. Here, we show that 5MP can suppress both general and repeat-associated non-AUG (RAN) translation by a common mechanism in a manner dependent on its interaction with eIF3. Essentially, 5MP displaces eIF5 through the eIF3c subunit within the preinitiation complex (PIC), thereby increasing the accuracy of initiation. In Drosophila, 5MP/Kra represses neuronal toxicity and enhances the lifespan in an FXTAS disease model. These results implicate 5MP in protecting cells from unwanted byproducts of non-AUG translation in neurodegeneration.


Asunto(s)
Codón Iniciador/genética , Proteínas de Unión al ADN/metabolismo , Factor 3 de Iniciación Eucariótica/metabolismo , Biosíntesis de Proteínas/genética , Expansión de Repetición de Trinucleótido/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Antígenos de Diferenciación/metabolismo , Proteínas de Unión al ADN/química , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Factor 2 Eucariótico de Iniciación/metabolismo , Factor 3 de Iniciación Eucariótica/química , Células HEK293 , Humanos , Masculino , Modelos Biológicos , Modelos Moleculares , Mutación/genética , Iniciación de la Cadena Peptídica Traduccional , Unión Proteica , Dominios Proteicos , Receptores Inmunológicos/metabolismo
9.
BMJ Open ; 10(10): e037980, 2020 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-33040006

RESUMEN

OBJECTIVES: This study aimed to characterise the exercise performed in UK cardiac rehabilitation (CR) and explore relationships between exercise dose and changes in physiological variables. DESIGN: Observational cohort study. SETTING: Outpatient community-based CR in Leeds, UK. Rehabilitation sessions were provided twice per week for 6 weeks. PARTICIPANTS: Sixty patients (45 male/15 female 33-86 years) were recruited following referral to local outpatient CR. OUTCOME MEASURES: The primary outcome was heart rate achieved during exercise sessions. Secondary outcomes were measured before and after CR and included incremental shuttle walk test (ISWT) distance and speed, blood pressure, brachial artery flow-mediated dilatation, carotid arterial stiffness and accelerometer-derived habitual physical activity behaviours. RESULTS: The mean % of heart rate reserve patients exercised at was low and variable at the start of CR (42%±16 %) and did not progress by the middle (48%±17 %) or end (48%±16 %) of the programme. ISWT performance increased following CR (440±150 m vs 633±217 m, p<0.001); however, blood pressure, body weight, endothelial function, arterial stiffness and habitual physical activity behaviours were unchanged following 6 weeks of CR (p>0.05). CONCLUSION: Patients in a UK CR cohort exercise at intensities that are variable but generally low. The exercise dose achieved using this CR format appears inadequate to impact markers of health. Attending CR had no effect on physical activity behaviours. Strategies to increase the dose of exercise patients achieve during CR and influence habitual physical activity behaviours may enhance the effectiveness of UK CR.


Asunto(s)
Rehabilitación Cardiaca , Estudios de Cohortes , Terapia por Ejercicio , Femenino , Humanos , Masculino , Reino Unido , Prueba de Paso
10.
Ann Otol Rhinol Laryngol ; 129(1): 39-45, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31416326

RESUMEN

BACKGROUND: Olfactory dysfunction is an important facet of numerous disease states ranging from sinonasal disease to neurocognitive disorders. Due to expense and/or logistical barriers, objective olfactory testing is not common. We describe the creation of a novel, essential oil-based smell test, Affordable Rapid Olfaction Measurement Array (AROMA), composed at 14 scents at different concentrations and demonstrate correlation of AROMA with the University of Pennsylvania Smell Identification Test (UPSIT), patient age, Sinonasal Outcomes Test (SNOT-22), and perceived loss of smell. METHODS: AROMA was developed for point-of-care olfactory testing and compared to the UPSIT, as well as subjective outcome measures as noted above. About 37 healthy controls were prospectively recruited to assess the reliability of AROMA using a test-retest protocol. An additional cohort of 38 participants with sinonasal disease were prospectively recruited to complete the AROMA and UPSIT, and were compared with a cohort of 30 healthy controls. Spearman correlation correlated AROMA and UPSIT results, patient age, SNOT-22, and perceived loss of smell. RESULTS: AROMA demonstrated good test-retest reliability (r = 0.85, P < .001). Spearman's rho correlation of AROMA to UPSIT was statistically significant at ρ = 0.75 (P < .001). SNOT-22, age, and perceived sense of smell were all significantly correlated with both AROMA (ρ = -0.548, -0.557, -0.642, respectively) and UPSIT (ρ = -0.367, -0.460, -0.552, respectively). CONCLUSION: AROMA has a strong correlation with UPSIT and may be more strongly correlated with sinonasal outcomes. Additionally, AROMA is reusable; level of odorant is not static; and AROMA can test both odor detection and identification. LEVEL OF EVIDENCE: 2b.


Asunto(s)
Odorantes , Aceites Volátiles , Trastornos del Olfato/diagnóstico , Adulto , Estudios de Casos y Controles , Técnicas y Procedimientos Diagnósticos/economía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas en el Punto de Atención , Umbral Sensorial , Prueba de Resultado Sino-Nasal
12.
Cell Rep ; 18(11): 2651-2663, 2017 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-28297669

RESUMEN

During eukaryotic translation initiation, eIF3 binds the solvent-accessible side of the 40S ribosome and recruits the gate-keeper protein eIF1 and eIF5 to the decoding center. This is largely mediated by the N-terminal domain (NTD) of eIF3c, which can be divided into three parts: 3c0, 3c1, and 3c2. The N-terminal part, 3c0, binds eIF5 strongly but only weakly to the ribosome-binding surface of eIF1, whereas 3c1 and 3c2 form a stoichiometric complex with eIF1. 3c1 contacts eIF1 through Arg-53 and Leu-96, while 3c2 faces 40S protein uS15/S13, to anchor eIF1 to the scanning pre-initiation complex (PIC). We propose that the 3c0:eIF1 interaction diminishes eIF1 binding to the 40S, whereas 3c0:eIF5 interaction stabilizes the scanning PIC by precluding this inhibitory interaction. Upon start codon recognition, interactions involving eIF5, and ultimately 3c0:eIF1 association, facilitate eIF1 release. Our results reveal intricate molecular interactions within the PIC, programmed for rapid scanning-arrest at the start codon.


Asunto(s)
Factor 3 de Iniciación Eucariótica/química , Factor 3 de Iniciación Eucariótica/metabolismo , Factor 5 Eucariótico de Iniciación/metabolismo , Iniciación de la Cadena Peptídica Traduccional , ARN Mensajero/metabolismo , Ribosomas/química , Ribosomas/metabolismo , Saccharomyces cerevisiae/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Factor 1 Eucariótico de Iniciación/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Mutación/genética , Unión Proteica , Subunidades de Proteína/metabolismo , ARN Mensajero/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
13.
Sex Roles ; 74(9): 436-449, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27152062

RESUMEN

Drawing on prior theoretical and empirical research on gender segregation within educational fields as well as occupations, we examine the pathways of college students who at least initially embark on a gender-atypical path. Specifically, we explore whether women who enter fields that are male-dominated are more likely to switch fields than their female peers who have chosen other fields, as well as whether men who enter female-dominated majors are more likely to subsequently switch fields than their male peers who have chosen a more normative field. We utilize a sample of 3702 students from a nationally representative dataset on U.S. undergraduates, the Beginning Postsecondary Students Longitudinal Study (BPS 2004/09). Logistic regression models examine the likelihood that students switch majors, controlling for students' social and academic background. Results reveal different patterns for men and women. Men who enter a female-dominated major are significantly more likely to switch majors than their male peers in other majors. By contrast, women in male-dominated fields are not more likely to switch fields compared to their female peers in other fields. The results are robust to supplementary analyses that include alternative specifications of the independent and dependent variables. The implications of our findings for the maintenance of gendered occupational segregation are discussed.

14.
Sci Educ ; 99(5): 819-836, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27667862

RESUMEN

Due to their potential impact on students' cognitive and non-cognitive outcomes, the negative attitudes towards science held by many elementary teachers are a critical issue that needs to be addressed. This study focuses on the science education of pre-service elementary teachers with the goal of improving their attitudes before they begin their professional lives as classroom teachers. Specifically, this study builds on a small body of research to examine whether exposure to inquiry-based science content courses that actively involve students in the collaborative process of learning and discovery can promote a positive change in attitudes towards science across several different dimensions. To examine this issue, surveys and administrative data were collected from over 200 students enrolled in the Hands on Science (HoS) program for pre-service teachers at the University of Texas at Austin, as well as more than 200 students in a comparison group enrolled in traditional lecture-style classes. Quantitative analyses reveal that after participating in HoS courses, pre-service teachers significantly increased their scores on scales measuring confidence, enjoyment, anxiety, and perceptions of relevance, while those in the comparison group experienced a decline in favorable attitudes to science. These patterns offer empirical support for the attitudinal benefits of inquiry-based instruction and have implications for the future learning opportunities available to students at all education levels.

15.
Med Sci Sports Exerc ; 46(4): 795-801, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24002344

RESUMEN

PURPOSE: This study evaluated the effects of acute hypoxia and physical exertion on marksmanship. METHODS: At each of five simulated altitudes (162 m, SL; 1015 m, 1K; 2146 m, 2K; 3085 m, 3 K; 3962 m, 4 K), subjects performed four shooting trials: at rest, immediately after a 60-s run with load, and twice more separated by 30-s rest. Arterial oxygen saturation (SaO2), HR, and ventilation rate (VR) were recorded. RESULTS: Both increasing altitude and exercise significantly (P < 0.05) decreased marksmanship. The shooting scores at 4 K were significantly lower than those at all other altitudes. There was a likely trend for scores at 3 K to be lower than those at SL and 1K (P = 0.06 and 0.07, respectively). The shooting score at rest was significantly greater than that in all trials after exercise. Partial recovery of marksmanship after exercise occurred. Altitude and exercise both significantly reduced SaO2 and increased VR. HR did not change with altitude but increased after exercise. There was a strong positive correlation (r = 0.84) between marksmanship and SaO2. There was a strong inverse correlation (r = -0.72) between marksmanship and VR, and a modest inverse correlation (r = -0.54) between marksmanship and HR. CONCLUSIONS: Increasing altitude impaired marksmanship, with a threshold at 3000-4000 m. The decreased marksmanship was closely related to decreased arterial oxygen saturation and increased ventilation, the latter increasing movement of the chest wall.


Asunto(s)
Altitud , Ejercicio Físico/fisiología , Armas de Fuego , Hipoxia/fisiopatología , Destreza Motora/fisiología , Adolescente , Adulto , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Oxígeno/sangre , Respiración , Adulto Joven
16.
Am J Eng Educ ; 4(1)2013.
Artículo en Inglés | MEDLINE | ID: mdl-25568814

RESUMEN

This paper examines gender inequality within the context of an upper-level high school engineering course recently offered in Texas. Data was collected from six high schools that serve students from a variety of backgrounds. Among the almost two hundred students who enrolled in this challenge-based engineering course, females constituted a clear minority, comprising only a total of 14% of students. Quantitative analyses of surveys administered at the beginning of the school year (Fall 2011) revealed statistically significant gender gaps in personal attitudes towards engineering and perceptions of engineering climate. Specifically, we found that compared to males, females reported lower interest in and intrinsic value for engineering, and expressed less confidence in their engineering skills. Additionally, female students felt that the classroom was less inclusive and viewed engineering occupations as less progressive. Gender disparities on all of these measures did not significantly decrease by the end of the school year (Spring 2012). Findings suggest that efforts to increase the representation of women in the engineering pipeline via increasing exposure in secondary education must contend not only with obstacles to recruiting high school girls into engineering courses, but must also work to remedy gender differences in engineering attitudes within the classroom.

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