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1.
BMC Womens Health ; 23(1): 179, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-37060006

RESUMEN

BACKGROUND: A growing body of evidence highlights how the COVID-19 pandemic has exacerbated gender inequalities in the US. This resulted in women being more vulnerable to economic insecurity and decreases in their overall well-being. One relevant issue that has been less explored is that of women's menstrual health experiences, including how inconsistent access to menstrual products may negatively impact their daily lives. METHODS: This qualitative study, conducted from March through May 2021, utilized in-depth interviews that were nested within a national prospective cohort study. The interviews (n = 25) were conducted with a sub-sample of cis-gender women living across the US who had reported challenges accessing products during the first year of the pandemic. The interviews sought to understand the barriers that contributed to experiencing menstrual product insecurity, and related coping mechanisms. Malterud's 'systematic text condensation', an inductive thematic analysis method, was utilized to analyze the qualitative transcripts. RESULTS: Respondents came from 17 different states across the U.S. Three key themes were identified: financial and physical barriers existed to consistent menstrual product access; a range of coping strategies in response to menstrual product insecurity, including dependence on makeshift and poorer quality materials; and heightened experiences of menstrual-related anxiety and shame, especially regarding the disclosure of their menstruating status to others as a result of inadequate menstrual leak protection. CONCLUSIONS: Addressing menstrual product insecurity is a critical step for ensuring that all people who menstruate can attain their most basic menstrual health needs. Key recommendations for mitigating the impact of menstrual product insecurity require national and state-level policy reform, such as the inclusion of menstrual products in existing safety net basic needs programs, and the reframing of menstrual products as essential items. Improved education and advocacy are needed to combat menstrual stigma.


Asunto(s)
COVID-19 , Productos para la Higiene Menstrual , Femenino , Humanos , Pandemias , Estudios Prospectivos , Menstruación/fisiología
2.
Health Care Women Int ; 44(5): 537-565, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-33825618

RESUMEN

As menstrual product advertising evolves within the United States, it is important to understand how advertising messages, which have been shown to impact self-esteem and feelings of shame, may be influencing young people today. We analyzed menstrual product advertising over ten years (2008-2018) through a survey (n = 198) and focus groups (n = 21) with college and graduate student-aged adults. Three themes emerged: an emphasis on femininity and shame; the presence and role of men in the menstrual process; and racial, gender and body type inclusivity. Advertising shifts toward messages of inclusivity may positively influence young people's perceptions toward their bodies and menstruation.


Asunto(s)
Publicidad , Productos para la Higiene Menstrual , Femenino , Masculino , Adulto , Humanos , Estados Unidos , Adolescente , Persona de Mediana Edad , Menstruación , Identidad de Género , Autoimagen
3.
Am J Public Health ; 112(4): 675-684, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35319956

RESUMEN

Objectives. To identify key effects of the pandemic and its economic consequences on menstrual product insecurity with implications for public health practice and policy. Methods. Study participants (n = 1496) were a subset of individuals enrolled in a national (US) prospective cohort study. Three survey waves were included (March‒October 2020). Menstrual product insecurity outcomes were explored with bivariate associations and logistic regression models to examine the associations between outcomes and income loss. Results. Income loss was associated with most aspects of menstrual product insecurity (adjusted odds ratios from 1.34 to 3.64). The odds of not being able to afford products for those who experienced income loss was 3.64 times (95% confidence interval [CI] = 2.14, 6.19) that of those who had no income loss and 3.95 times (95% CI = 1.78, 8.79) the odds for lower-income participants compared with higher-income participants. Conclusions. Pandemic-related income loss was a strong predictor of menstrual product insecurity, particularly for populations with lower income and educational attainment. Public Health Implications. Provision of free or subsidized menstrual products is needed by vulnerable populations and those most impacted by pandemic-related income loss.(Am J Public Health. 2022;112(4):675-684. (https://doi.org/10.2105/AJPH.2021.306674).


Asunto(s)
COVID-19 , Productos para la Higiene Menstrual , COVID-19/epidemiología , Estudios Transversales , Abastecimiento de Alimentos , Humanos , Estudios Prospectivos , Estados Unidos/epidemiología
4.
Int J Mol Sci ; 22(2)2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33477414

RESUMEN

Genetic code expansion has largely focused on the reassignment of amber stop codons to insert single copies of non-canonical amino acids (ncAAs) into proteins. Increasing effort has been directed at employing the set of aminoacyl tRNA synthetase (aaRS) variants previously evolved for amber suppression to incorporate multiple copies of ncAAs in response to sense codons in Escherichia coli. Predicting which sense codons are most amenable to reassignment and which orthogonal translation machinery is best suited to each codon is challenging. This manuscript describes the directed evolution of a new, highly efficient variant of the Methanosarcina barkeri pyrrolysyl orthogonal tRNA/aaRS pair that activates and incorporates tyrosine. The evolved M. barkeri tRNA/aaRS pair reprograms the amber stop codon with 98.1 ± 3.6% efficiency in E. coli DH10B, rivaling the efficiency of the wild-type tyrosine-incorporating Methanocaldococcus jannaschii orthogonal pair. The new orthogonal pair is deployed for the rapid evaluation of sense codon reassignment potential using our previously developed fluorescence-based screen. Measurements of sense codon reassignment efficiencies with the evolved M. barkeri machinery are compared with related measurements employing the M. jannaschii orthogonal pair system. Importantly, we observe different patterns of sense codon reassignment efficiency for the M. jannaschii tyrosyl and M. barkeri pyrrolysyl systems, suggesting that particular codons will be better suited to reassignment by different orthogonal pairs. A broad evaluation of sense codon reassignment efficiencies to tyrosine with the M. barkeri system will highlight the most promising positions at which the M. barkeri orthogonal pair may infiltrate the E. coli genetic code.


Asunto(s)
Aminoacil-ARNt Sintetasas/genética , Codón/genética , Evolución Molecular Dirigida , ARN de Transferencia/genética , Aminoácidos/genética , Codón de Terminación/genética , Escherichia coli/genética , Código Genético/genética , Methanosarcina barkeri/genética , Biosíntesis de Proteínas/genética , Tirosina/genética
5.
Chembiochem ; 21(16): 2274-2286, 2020 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-32203635

RESUMEN

A quantitative understanding of how system composition and molecular properties conspire to determine the fidelity of translation is lacking. Our strategy directs an orthogonal tRNA to directly compete against endogenous tRNAs to decode individual targeted codons in a GFP reporter. Sets of directed sense codon reassignment measurements allow the isolation of particular factors contributing to translational fidelity. In this work, we isolated the effect of tRNA concentration on translational fidelity by evaluating reassignment of the 15 least commonly employed E. coli sense codons. Eight of the rarely used codons are reassigned with greater than 20 % efficiency. Both tRNA abundance and codon demand moderately inversely correlate with reassignment efficiency. Furthermore, the reassignment of rarely used codons does not appear to confer a fitness advantage relative to reassignment of other codons. These direct competition experiments also map potential targets for genetic code expansion. The isoleucine AUA codon is particularly attractive for the incorporation of noncanonical amino acids, with a nonoptimized reassignment efficiency of nearly 70 %.


Asunto(s)
Codón/genética , Biosíntesis de Proteínas , ARN de Transferencia/genética , Sustitución de Aminoácidos , Escherichia coli/genética , Genoma Bacteriano/genética , Proteómica
6.
Biochemistry ; 57(19): 2762-2774, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29668270

RESUMEN

The relative quantitative importance of the factors that determine the fidelity of translation is largely unknown, which makes predicting the extent to which the degeneracy of the genetic code can be broken challenging. Our strategy of using orthogonal tRNA/aminoacyl tRNA synthetase pairs to precisely direct the incorporation of a single amino acid in response to individual sense and nonsense codons provides a suite of related data with which to examine the plasticity of the code. Each directed sense codon reassignment measurement is an in vivo competition experiment between the introduced orthogonal translation machinery and the natural machinery in Escherichia coli. This report discusses 20 new, related genetic codes, in which a targeted E. coli wobble codon is reassigned to tyrosine utilizing the orthogonal tyrosine tRNA/aminoacyl tRNA synthetase pair from Methanocaldococcus jannaschii. One at a time, reassignment of each targeted sense codon to tyrosine is quantified in cells by measuring the fluorescence of GFP variants in which the essential tyrosine residue is encoded by a non-tyrosine codon. Significantly, every wobble codon analyzed may be partially reassigned with efficiencies ranging from 0.8 to 41%. The accumulation of the suite of data enables a qualitative dissection of the relative importance of the factors affecting the fidelity of translation. While some correlation was observed between sense codon reassignment and either competing endogenous tRNA abundance or changes in aminoacylation efficiency of the altered orthogonal system, no single factor appears to predominately drive translational fidelity. Evaluation of relative cellular fitness in each of the 20 quantitatively characterized proteome-wide tyrosine substitution systems suggests that at a systems level, E. coli is robust to missense mutations.


Asunto(s)
Codón/genética , Código Genético/genética , Biosíntesis de Proteínas/genética , Tirosina/genética , Sustitución de Aminoácidos/genética , Aminoacil-ARNt Sintetasas/genética , Escherichia coli/genética , Proteoma/genética , ARN de Transferencia/genética
7.
Nucleic Acids Res ; 44(21): 10042-10050, 2016 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-27915288

RESUMEN

Breaking the degeneracy of the genetic code via sense codon reassignment has emerged as a way to incorporate multiple copies of multiple non-canonical amino acids into a protein of interest. Here, we report the modification of a normally orthogonal tRNA by a host enzyme and show that this adventitious modification has a direct impact on the activity of the orthogonal tRNA in translation. We observed nearly equal decoding of both histidine codons, CAU and CAC, by an engineered orthogonal M. jannaschii tRNA with an AUG anticodon: tRNAOpt We suspected a modification of the tRNAOptAUG anticodon was responsible for the anomalous lack of codon discrimination and demonstrate that adenosine 34 of tRNAOptAUG is converted to inosine. We identified tRNAOptAUG anticodon loop variants that increase reassignment of the histidine CAU codon, decrease incorporation in response to the histidine CAC codon, and improve cell health and growth profiles. Recognizing tRNA modification as both a potential pitfall and avenue of directed alteration will be important as the field of genetic code engineering continues to infiltrate the genetic codes of diverse organisms.


Asunto(s)
Codón , Methanococcus/genética , ARN de Transferencia/metabolismo , Adenosina/genética , Adenosina/metabolismo , Anticodón , Evolución Molecular , Ingeniería Genética/métodos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Histidina/genética , Inosina/genética , Inosina/metabolismo , ARN de Transferencia/genética
8.
Anal Biochem ; 521: 59-71, 2017 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-28062210

RESUMEN

Tuberculosis is the leading cause of death from infectious disease worldwide. The low sensitivity, extended processing time, and high expense of current diagnostics are major challenges to the detection and treatment of tuberculosis. Mycobacterium tuberculosis ornithine transcarbamylase (Mtb OTC, Rv1656) has been identified in the urine of patients with active TB infection and is a promising target for point-of-care diagnostics. Specific binding proteins with low nanomolar affinities for Mtb OTC were selected from a phage display library built upon a hyperthermostable Sso7d scaffold. Phage particles displaying Sso7d variants were utilized to generate a sandwich ELISA-based assay for Mtb OTC. The assay response is linear between 2 ng/mL and 125 ng/mL recombinant Mtb OTC and has a limit of detection of 400 pg/mL recombinant Mtb OTC. The assay employing a phage-based detection reagent is comparable to commercially-available antibody-based biosensors. Importantly, the assay maintains functionality at both neutral and basic pH in presence of salt and urea over the range of concentrations typical for human urine. Phage-based diagnostic systems may feature improved physical stability and cost of production relative to traditional antibody-based reagents, without sacrificing specificity and sensitivity.


Asunto(s)
Anticuerpos Antibacterianos/metabolismo , Anticuerpos Monoclonales/metabolismo , Bioensayo/métodos , Técnicas de Visualización de Superficie Celular/métodos , Mycobacterium tuberculosis/inmunología , Sistemas de Atención de Punto , Tuberculosis/diagnóstico , Secuencia de Aminoácidos , Animales , Anticuerpos Antibacterianos/inmunología , Anticuerpos Monoclonales/inmunología , Proteínas Arqueales/metabolismo , Proteínas de Unión al ADN/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Biblioteca de Péptidos , Homología de Secuencia de Aminoácido , Sulfolobus solfataricus/metabolismo , Temperatura , Tuberculosis/metabolismo , Tuberculosis/microbiología
9.
Gen Dent ; 64(3): 60-3, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27148659

RESUMEN

Antithrombotic medications, including antiplatelets and anticoagulants, are used by millions of patients to prevent stroke or heart attack. When these patients present for dental surgery, a decision must be made whether to continue the antithrombotic medication and risk a bleeding problem or to interrupt the medication and risk an embolic complication such as a stroke or heart attack. In patients taking antithrombotic medications, a small risk of postoperative bleeding after dental extractions must be weighed against a small risk of stroke or heart attack when these medications are interrupted. This case report discusses an episode of minor postextraction bleeding in a patient taking combination anticoagulant and antiplatelet therapy. Antithrombotic therapy generally should not be interrupted for dental procedures, as the prognosis of potential postextraction bleeding that could result from antithrombotic continuation is almost always better than the prognosis of a potential stroke or heart attack that could follow antithrombotic interruption.


Asunto(s)
Fibrinolíticos/efectos adversos , Hemorragia Posoperatoria/inducido químicamente , Extracción Dental/efectos adversos , Anciano , Humanos , Masculino , Diente Molar/cirugía
10.
Biochemistry ; 54(50): 7355-64, 2015 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-26536053

RESUMEN

Understanding the interactions that drive the fidelity of the genetic code and the limits to which modifications can be made without breaking the translational system has practical implications for understanding the molecular mechanisms of evolution as well as expanding the set of encodable amino acids, particularly those with chemistries not provided by Nature. Because 61 sense codons encode 20 amino acids, reassigning the meaning of sense codons provides an avenue for biosynthetic modification of proteins, furthering both fundamental and applied biochemical research. We developed a simple screen that exploits the absolute requirement for fluorescence of an active site tyrosine in green fluorescent protein (GFP) to probe the pliability of the degeneracy of the genetic code. Our screen monitors the restoration of the fluorophore of GFP by incorporation of a tyrosine in response to a sense codon typically assigned another meaning in the genetic code. We evaluated sense codon reassignment at four of the 21 sense codons read through wobble interactions in Escherichia coli using the Methanocaldococcus jannaschii orthogonal tRNA/aminoacyl tRNA synthetase pair originally developed and commonly used for amber stop codon suppression. By changing only the anticodon of the orthogonal tRNA, we achieved sense codon reassignment efficiencies between 1% (Phe UUU) and 6% (Lys AAG). Each of the orthogonal tRNAs preferentially decoded the codon traditionally read via a wobble interaction in E. coli with the exception of the orthogonal tRNA with an AUG anticodon, which incorporated tyrosine in response to both the His CAU and His CAC codons with approximately equal frequencies. We applied our screen in a high-throughput manner to evaluate a 10(9)-member combined tRNA/aminoacyl tRNA synthetase library to identify improved sense codon reassigning variants for the Lys AAG codon. A single rapid screen with the ability to broadly evaluate reassignable codons will facilitate identification and improvement of the combinations of sense codons and orthogonal pairs that display efficient reassignment.


Asunto(s)
Codón , Anticodón , Escherichia coli/genética , Proteínas Fluorescentes Verdes/química , Methanocaldococcus/genética , Modelos Moleculares , ARN de Transferencia/genética
12.
Health Res Policy Syst ; 12: 16, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24690310

RESUMEN

BACKGROUND: Rapid urban population growth is of global concern as it is accompanied with several new health challenges. The urban poor who reside in informal settlements are more vulnerable to these health challenges. Lack of formal government public health facilities for the provision of health care is also a common phenomenon among communities inhabited by the urban poor. To help ameliorate this situation, an innovative urban primary health system was introduced in urban Ghana, based on the milestones model developed with the rural Community-Based Health Planning and Services (CHPS) system. This paper provides an overview of innovative experiences adapted while addressing these urban health issues, including the process of deriving constructive lessons needed to inform discourse on the design and implementation of the sustainable Community-Based Health Planning and Services (CHPS) model as a response to urban health challenges in Southern Ghana. METHODS: This research was conducted during the six-month pilot of the urban CHPS programme in two selected areas acting as the intervention and control arms of the design. Daily routine data were collected based on milestones initially delineated for the rural CHPS model in the control communities whilst in the intervention communities, some modifications were made to the rural milestones. RESULTS: The findings from the implementation activities revealed that many of the best practices derived from the rural CHPS experiment could not be transplanted to poor urban settlements due to the unique organizational structures and epidemiological characteristics found in the urban context. For example, constructing Community Health Compounds and residential facilities within zones, a central component to the rural CHPS strategy, proved inappropriate for the urban sector. Night and weekend home visit schedules were initiated to better accommodate urban residents and increase coverage. The breadth of the disease burden of the urban residents also requires a broader expertise and training of the CHOs. CONCLUSIONS: Access to improved urban health services remains a challenge. However, current policy guidelines for the implementation of a primary health model based on rural experiences and experimental design requires careful review and modifications to meet the needs of the urban settings.


Asunto(s)
Atención a la Salud/organización & administración , Atención Primaria de Salud/organización & administración , Servicios Urbanos de Salud/organización & administración , Enfermería en Salud Comunitaria/organización & administración , Servicios de Salud Comunitaria/organización & administración , Servicios de Salud Comunitaria/provisión & distribución , Costo de Enfermedad , Difusión de Innovaciones , Equipos y Suministros/provisión & distribución , Femenino , Ghana , Instituciones de Salud/provisión & distribución , Planificación en Salud , Política de Salud , Humanos , Masculino , Selección de Personal , Proyectos Piloto , Servicios de Salud Rural , Servicios Urbanos de Salud/provisión & distribución , Voluntarios/educación , Voluntarios/organización & administración
13.
Front Genet ; 15: 1386299, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38706795

RESUMEN

The in vivo codon decoding preferences of tRNAs with an authentic adenosine residue at position 34 of the anticodon, the wobble position, are largely unexplored because very few unmodified A34 tRNA genes exist across the three domains of life. The expanded wobble rules suggest that unmodified adenosine pairs most strongly with uracil, modestly with cytosine, and weakly with guanosine and adenosine. Inosine, a modified adenosine, on the other hand, pairs strongly with both uracil and cytosine and to a lesser extent adenosine. Orthogonal pair directed sense codon reassignment experiments offer a tool with which to interrogate the translational activity of A34 tRNAs because the introduced tRNA can be engineered with any anticodon. Our fluorescence-based screen utilizes the absolute requirement of tyrosine at position 66 of superfolder GFP for autocatalytic fluorophore formation. The introduced orthogonal tRNA competes with the endogenous translation machinery to incorporate tyrosine in response to a codon typically assigned another meaning in the genetic code. We evaluated the codon reassignment efficiencies of 15 of the 16 possible orthogonal tRNAs with A34 anticodons. We examined the Sanger sequencing chromatograms for cDNAs from each of the reverse transcribed tRNAs for evidence of inosine modification. Despite several A34 tRNAs decoding closely-related C-ending codons, partial inosine modification was detected for only three species. These experiments employ a single tRNA body with a single attached amino acid to interrogate the behavior of different anticodons in the background of in vivo E. coli translation and greatly expand the set of experimental measurements of the in vivo function of A34 tRNAs in translation. For the most part, unmodified A34 tRNAs largely pair with only U3 codons as the original wobble rules suggest. In instances with GC pairs in the first two codon positions, unmodified A34 tRNAs decode the C- and G-ending codons as well as the expected U-ending codon. These observations support the "two-out-of-three" and "strong and weak" codon hypotheses.

14.
Glob Health Sci Pract ; 11(3)2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37348938

RESUMEN

There is a growing global interest in puberty and early adolescence and the importance of ensuring young people have the information and support they need during this critical phase of transition in the life course. This article highlights an adaptable model being used to support the development of contextually appropriate puberty education, in the form of illustrated and often bilingual books, for early adolescent girls and boys in countries around the world. This youth-centered participatory research and design model, which relies on the generation of community and government partnerships, has been employed in 10 countries thus far. Valuable learning has been documented from various contexts, including the approach's flexibility in adapting to the inputs of government and community members, incorporating local buy-in as a key ingredient for sustainability, using in-country experts for social and cultural appropriateness of illustrations and translations, and ensuring that the authentic youth voices captured through the participatory data collection and field-testing shape the educational content. The continuous integration of insights and perceptions of adults who influence young people's lives into the development process is also essential to enabling the uptake of puberty content in each new country. Parents, educators, youth service providers, and government officials are often the gatekeepers to young adolescents receiving puberty content and are thus critical to the process. This review of more than a decade of experience using this model underscores the essentiality of 2 key components-local partnership and participatory data collection-and highlights the importance of flexible approaches that are adapted to the unique sociocultural and environmental conditions in each country context.


Asunto(s)
Aprendizaje , Pubertad , Masculino , Femenino , Adulto , Adolescente , Humanos
15.
Front Chem ; 10: 815788, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35252113

RESUMEN

The expansion of the genetic code beyond a single type of noncanonical amino acid (ncAA) is hindered by inefficient machinery for reassigning the meaning of sense codons. A major obstacle to using directed evolution to improve the efficiency of sense codon reassignment is that fractional sense codon reassignments lead to heterogeneous mixtures of full-length proteins with either a ncAA or a natural amino acid incorporated in response to the targeted codon. In stop codon suppression systems, missed incorporations lead to truncated proteins; improvements in activity may be inferred from increased protein yields or the production of downstream reporters. In sense codon reassignment, the heterogeneous proteins produced greatly complicate the development of screens for variants of the orthogonal machinery with improved activity. We describe the use of a previously-reported fluorescence-based screen for sense codon reassignment as the first step in a directed evolution workflow to improve the incorporation of a ncAA in response to the Arg AGG sense codon. We first screened a library with diversity introduced into both the orthogonal Methanocaldococcus jannaschii tyrosyl tRNA anticodon loop and the cognate aminoacyl tRNA synthetase (aaRS) anticodon binding domain for variants that improved incorporation of tyrosine in response to the AGG codon. The most efficient variants produced fluorescent proteins at levels indistinguishable from the E. coli translation machinery decoding tyrosine codons. Mutations to the M. jannaschii aaRS that were found to improve tyrosine incorporation were transplanted onto a M. jannaschii aaRS evolved for the incorporation of para-azidophenylalanine. Improved ncAA incorporation was evident using fluorescence- and mass-based reporters. The described workflow is generalizable and should enable the rapid tailoring of orthogonal machinery capable of activating diverse ncAAs to any sense codon target. We evaluated the selection based improvements of the orthogonal pair in a host genomically engineered for reduced target codon competition. Using this particular system for evaluation of arginine AGG codon reassignment, however, E. coli strains with genomes engineered to remove competing tRNAs did not outperform a standard laboratory E. coli strain in sense codon reassignment.

16.
Front Mol Biosci ; 9: 938114, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36120552

RESUMEN

The extent to which alteration of endogenous tRNA modifications may be exploited to improve genetic code expansion efforts has not been broadly investigated. Modifications of tRNAs are strongly conserved evolutionarily, but the vast majority of E. coli tRNA modifications are not essential. We identified queuosine (Q), a non-essential, hypermodified guanosine nucleoside found in position 34 of the anticodons of four E. coli tRNAs as a modification that could potentially be utilized to improve sense codon reassignment. One suggested purpose of queuosine modification is to reduce the preference of tRNAs with guanosine (G) at position 34 of the anticodon for decoding cytosine (C) ending codons over uridine (U) ending codons. We hypothesized that introduced orthogonal translation machinery with adenine (A) at position 34 would reassign U-ending codons more effectively in queuosine-deficient E. coli. We evaluated the ability of introduced orthogonal tRNAs with AUN anticodons to reassign three of the four U-ending codons normally decoded by Q34 endogenous tRNAs: histidine CAU, asparagine AAU, and aspartic acid GAU in the presence and absence of queuosine modification. We found that sense codon reassignment efficiencies in queuosine-deficient strains are slightly improved at Asn AAU, equivalent at His CAU, and less efficient at Asp GAU codons. Utilization of orthogonal pair-directed sense codon reassignment to evaluate competition events that do not occur in the standard genetic code suggests that tRNAs with inosine (I, 6-deaminated A) at position 34 compete much more favorably against G34 tRNAs than Q34 tRNAs. Continued evaluation of sense codon reassignment following targeted alterations to endogenous tRNA modifications has the potential to shed new light on the web of interactions that combine to preserve the fidelity of the genetic code as well as identify opportunities for exploitation in systems with expanded genetic codes.

17.
Front Reprod Health ; 4: 1018217, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36339773

RESUMEN

Adolescent girls in the U.S.A. often lack sufficient education on pubertal and menstrual health topics. This educational gap may be growing given the current decline in American elementary and middle schools' delivery of sexual health education. Furthermore, little is known about the actual scope and quality of existing menstruation and puberty education in U.S.A. schools. This paper provides insights into some of the challenges with the delivery of menstruation and puberty education in schools. Qualitative and participatory research methodologies were utilized with Black and Latina girls ages 15-19 and adults working with youth in three U.S.A. cities (Chicago, Los Angeles, and New York City), exploring experiences of menstruation within school and family contexts. Findings revealed tension between school responsibility and family authority in providing menstruation and puberty education in schools, school- and teacher-related delivery challenges, and inadequate and disengaging menstruation and puberty content. Further research is needed on the effectiveness and best practices for providing this education in schools, including improved understanding on student and parent preferences, delivery mediums and the scope of content.

18.
Health Policy Plan ; 37(3): 420-427, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-34984450

RESUMEN

Ever since the 1990s, implementation research in Ghana has guided the development of policies and practices that are essential to establishing community-based primary health care. In response to evidence emerging from this research, the Community-based Health Planning and Services (CHPS) policy was promulgated in 1999 to scale-up results. However, during the first decade of CHPS operation, national monitoring showed that its pace of coverage expansion was unacceptably slow. In 2010, the Ghana Health Service launched a 5-year plausibility trial of CHPS reform for testing ways to accelerate scale-up. This initiative, known as the Ghana Essential Health Intervention Program (GEHIP), included a knowledge management component for establishing congruence of knowledge generation and flow with the operational system that GEHIP evidence was intended to reform. Four Upper East Region districts served as trial areas, while seven districts were comparison areas. Interventions tested means of developing the upward flow of information based on perspectives of district managers, sub-district supervisors and community-level workers. GEHIP also endeavoured to improve procedures for the downward flow and utilization of policy guidelines. Field exchanges were convened for providing national, regional and district leaders with opportunities for participatory learning about GEHIP implementation innovations. This systems approach facilitated the process of augmenting the communication of evidence with practical field experience. Scientific rigor associated with the production of evidence was thereby integrated into management decision-making processes in ways that institutionalized learning at all levels. The GEHIP knowledge management system functioned as a prototype for guiding the planning of a national knowledge management strategy. A follow-up project transferred its mechanisms from the Upper East Regional Health Administration to the Policy Planning Monitoring and Evaluation Division of the Ghana Health Service in Accra.


Asunto(s)
Servicios de Salud Comunitaria , Investigación sobre Servicios de Salud , Ghana , Programas de Gobierno , Humanos , Atención Primaria de Salud
19.
Front Reprod Health ; 3: 725805, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36303999

RESUMEN

There has been a growth in menstrual equity policy advancements in the U.S.A. in recent years; with much of the new legislation prioritizing the needs of adolescent girls in schools. New York City, a predecessor of this movement, was the first U.S.A. locality to pass such legislation in 2016. The aim of this case study was to better understand the various factors which led to the development, passage and initial implementation of New York City's Menstrual Equity in Schools Policy. Data collection methods included a desk review and qualitative assessment with several actors involved across the policy and introduction phases. Key findings included (1) the utility of community narratives and a pilot project as a means for overcoming initial skepticisms, proving feasibility, and generating support; (2) the importance of policy champions for overcoming fiscal objections and navigating political discourse; and (3) lessons learned from early implementation efforts, including variance in awareness and distribution models. This case study yields valuable insights into the practical considerations when designing or implementing policies aimed at tackling issues of menstrual equity within school settings.

20.
Front Reprod Health ; 3: 787277, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36304028

RESUMEN

Background: In recent years there has been growing momentum in the USA around addressing issues of "menstrual equity" and "period poverty," including a proliferation of university-level initiatives seeking to provide access to free menstrual products. This multiple case study examined four such efforts at a diversity of tertiary institutions to identify the factors that facilitated or impeded success. Methods: We conducted a qualitative multiple case study, including a desk review and key informant interviews with student and administrative actors from universities with free menstrual product initiatives. We sought to identify key learning regarding common challenges and obstacles, enabling factors which supported success and sustainability, and practical learning for future initiatives. From the desk review, four schools (n = 4) were purposively selected to represent a range of geographic regions, student population size, and university type. Purposive sampling was used to identify students and administrators engaged in the menstrual equity initiatives on each campus (n = 20; 4-6 per school). Data from the desk review and interviews were analyzed using thematic analysis. Results: Key themes included (1) the critical role of champions, (2) the importance of social and financial support, (3) challenges diffusing menstrual equity from pilot to scale, and (4) recommendations for future initiatives. University initiatives varied greatly in terms of their scope, funding, and implementation strategy. Conclusion: This multiple case study provides valuable insights regarding the facilitating factors and obstacles faced by initiatives providing free menstrual products at universities. To date, these initiatives have proven successful across the four case studies; however, in most cases, the scope of the initiatives was constrained by limited resources and sustainability concerns. Future campus menstrual equity strategies would benefit from cross-institutional learning and dialogue highlighting design and implementation successes and challenges.

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