Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 119(20): e2201113119, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35533275

RESUMO

The deadly toxin α-amanitin is a bicyclic octapeptide biosynthesized on ribosomes. A phylogenetically disjunct group of mushrooms in Agaricales (Amanita, Lepiota, and Galerina) synthesizes α-amanitin. This distribution of the toxin biosynthetic pathway is possibly related to the horizontal transfer of metabolic gene clusters among taxonomically unrelated mushrooms with overlapping habitats. Here, our work confirms that two biosynthetic genes, P450-29 and FMO1, are oxygenases important for amanitin biosynthesis. Phylogenetic and genetic analyses of these genes strongly support their origin through horizontal transfer, as is the case for the previously characterized biosynthetic genes MSDIN and POPB. Our analysis of multiple genomes showed that the evolution of the α-amanitin biosynthetic pathways in the poisonous agarics in the Amanita, Lepiota, and Galerina clades entailed distinct evolutionary pathways including gene family expansion, biosynthetic genes, and genomic rearrangements. Unrelated poisonous fungi produce the same deadly amanitin toxins using variations of the same pathway. Furthermore, the evolution of the amanitin biosynthetic pathway(s) in Amanita species generates a much wider range of toxic cyclic peptides. The results reported here expand our understanding of the genetics, diversity, and evolution of the toxin biosynthetic pathway in fungi.


Assuntos
Amanitinas , Toxinas Biológicas , Amanita/genética , Amanitinas/genética , Evolução Biológica , Vias Biossintéticas/genética , Transferência Genética Horizontal
2.
Nurs Ethics ; : 9697330241238347, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38476080

RESUMO

BACKGROUND: Unit-based critical care nurse leaders (UBCCNL) play a role in exemplifying ethical leadership, addressing moral distress, and mitigating contributing factors to moral distress on their units. Despite several studies examining the experience of moral distress by bedside nurses, knowledge is limited regarding the UBCCNL's experience. RESEARCH AIM: The aim of this study was to gain a deeper understanding of the lived experiences of Alabama UBCCNLs regarding how they experience, cope with, and address moral distress. RESEARCH DESIGN: A qualitative descriptive design and inductive thematic analysis guided the investigation. A screening and demographics questionnaire and a semi-structured interview protocol were the tools of data collection. PARTICIPANT AND RESEARCH CONTEXT: Data were collected from 10 UBCCNLs from seven hospitals across the state of Alabama from February to July 2023. ETHICAL CONSIDERATIONS: This study was approved by the Institutional Review Board at the University of Alabama in Huntsville. Informed consent was obtained from participants prior to data collection. FINDINGS: UBCCNLs experience moral distress frequently due to a variety of systemic and organizational barriers. Feelings of powerlessness tended to precipitate moral distress among UBCCNLs. Despite moral distress resulting in increased advocacy and empathy, UBCCNLs may experience a variety of negative responses resulting from moral distress. UBCCNLs may utilize internal and external mechanisms to cope with and address moral distress. CONCLUSIONS: The UBCCNL's experience of moral distress is not dissimilar from bedside staff; albeit, moral distress does occur as a result of the responsibilities of leadership and the associated systemic barriers that UBCCNLs are privier to. When organizations allocate resources for addressing moral distress, they should be convenient to leaders and staff. The UBCCNL perspective should be considered in the development of future moral distress measurement tools and interventions. Future research exploring the relationship between empathy and moral distress among nurse leaders is needed.

3.
Nurs Crit Care ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38400568

RESUMO

BACKGROUND: Moral distress (MD) occurs when clinicians are constrained from taking what they believe to be ethically appropriate actions. When unattended, MD may result in moral injury and/or suffering. Literature surrounding how unit-based critical care nurse leaders address MD in practice is limited. AIM: The aim of this study was to explore how ICU nurse leaders recognize and address MD among their staff. STUDY DESIGN: Qualitative descriptive with inductive thematic analysis. RESULTS: Five ICU nurse leaders participated in a one-time individual interview. Interview results suggest that (1) ICU nurse leaders can recognize and address MD among their staff and (2) nurse leaders experience MD themselves, which may be exacerbated by their leadership role and responsibilities. CONCLUSIONS: Further research is needed to develop interventions aimed at addressing MD among nurse leaders and equipping nurse leaders with the skills to identify and address MD within their staff and themselves. RELEVANCE TO CLINICAL PRACTICE: MD is an unavoidable phenomenon ICU nurse leaders are challenged with addressing in their day-to-day practice. As leaders, recognizing and addressing MD is a necessary task relating to mitigating burnout and turnover and addressing well-being among staff within the ICU.

4.
BMC Public Health ; 23(1): 41, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609291

RESUMO

BACKGROUND: The Australian First Few X (FFX) Household Transmission Project for COVID-19 was the first prospective, multi-jurisdictional study of its kind in Australia. The project was undertaken as a partnership between federal and state health departments and the Australian Partnership for Preparedness Research on Infectious Disease Emergencies (APPRISE) and was active from April to October 2020. METHODS: We aimed to identify and explore the challenges and strengths of the Australian FFX Project to inform future FFX study development and integration into pandemic preparedness plans. We asked key stakeholders and partners involved with implementation to identify and rank factors relating to the strengths and challenges of project implementation in two rounds of modified Delphi surveys. Key representatives from jurisdictional health departments were then interviewed to contextualise findings within public health processes and information needs to develop a final set of recommendations for FFX study development in Australia. RESULTS: Four clear recommendations emerged from the evaluation. Future preparedness planning should aim to formalise and embed partnerships between health departments and researchers to help better integrate project data collection into core public health surveillance activities. The development of functional, adaptable protocols with pre-established ethics and governance approvals and investment in national data infrastructure were additional priority areas noted by evaluation participants. CONCLUSION: The evaluation provided a great opportunity to consolidate lessons learnt from the Australian FFX Household Transmission Project. The developed recommendations should be incorporated into future pandemic preparedness plans in Australia to enable effective implementation and increase local utility and value of the FFX platform within emergency public health response.


Assuntos
COVID-19 , Humanos , Estudos Prospectivos , Austrália/epidemiologia , COVID-19/epidemiologia , Saúde Pública
5.
Nurs Educ Perspect ; 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37948042

RESUMO

ABSTRACT: Competence in interprofessional collaboration is essential for safe patient outcomes. This study examined the impact of an interprofessional telehealth pharmacology simulation on prelicensure nursing and pharmacy students' perceptions of interprofessional roles. A pretest-posttest design was used to compare participants' perceptions of interprofessional roles prior to and following the simulation. Data were collected using the Interdisciplinary Education Perception Scale (IEPS). Paired-samples t-tests showed statistically significant increases in scores for both the full IEPS (n = 99) and two subscales, Competency and Autonomy (n = 99) and Perception of Actual Cooperation (n = 99). Nurse educators should provide regular interprofessional experiences to foster learners' competence in interprofessional collaboration and communication.

6.
Nurs Ethics ; 30(7-8): 939-959, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37845832

RESUMO

Moral distress (MD) is well-documented within the nursing literature and occurs when constraints prevent a correct course of action from being implemented. The measured frequency of MD has increased among nurses over recent years, especially since the COVID-19 Pandemic. MD is less understood among nurse leaders than other populations of nurses. A qualitative systematic review was conducted with the aim to synthesize the experiences of MD among nurse leaders. This review involved a search of three databases (Medline, CINAHL, and APA PsychINFO) which resulted in the retrieval of 303 articles. PRISMA review criteria guided authors during the article review and selection process. Following the review, six articles were identified meeting review criteria and quality was assessed using the Critical Appraisal Skills Programme (CASP) Checklist for qualitative studies. No ethical review was required for this systematic review. The six studies included in this review originated from the United States, Brazil, Turkey, and Iran. Leadership roles ranged from unit-based leadership to executive leadership. Assigned quality scores based upon CASP criteria ranged from 6 to 9 (moderate to high quality). Three analytical themes emerged from the synthesis: (1) moral distress is consuming; (2) constrained by the system; and (3) adapt to overcome. The unique contributors of MD among nurse leaders include the leadership role itself and challenges navigating moral situations as they arise. The nurse leader perspective should be considered in the development of future MD interventions.


Assuntos
Cuidados de Enfermagem , Pandemias , Humanos , Liderança , Pesquisa Qualitativa , Princípios Morais
7.
Artigo em Inglês | MEDLINE | ID: mdl-35871459

RESUMO

BACKGROUND: Household studies are crucial for understanding the transmission of SARS-CoV-2 infection, which may be underestimated from PCR testing of respiratory samples alone. We aim to combine the assessment of household mitigation measures; nasopharyngeal, saliva, and stool PCR testing; along with mucosal and systemic SARS-CoV-2-specific antibodies, to comprehensively characterize SARS-CoV-2 infection and transmission in households. METHODS: Between March and September 2020, we obtained samples from 92 participants in 26 households in Melbourne, Australia, in a 4-week period following the onset of infection with ancestral SARS-CoV-2 variants. RESULTS: The secondary attack rate was 36% (24/66) when using nasopharyngeal swab (NPS) PCR positivity alone. However, when respiratory and nonrespiratory samples were combined with antibody responses in blood and saliva, the secondary attack rate was 76% (50/66). SARS-CoV-2 viral load of the index case and household isolation measures were key factors that determine secondary transmission. In 27% (7/26) of households, all family members tested positive by NPS for SARS-CoV-2 and were characterized by lower respiratory Ct values than low transmission families (Median 22.62 vs. 32.91; IQR 17.06-28.67 vs. 30.37-34.24). High transmission families were associated with enhanced plasma antibody responses to multiple SARS-CoV-2 antigens and the presence of neutralizing antibodies. Three distinguishing saliva SARS-CoV-2 antibody features were identified according to age (IgA1 to Spike 1, IgA1 to nucleocapsid protein (NP)), suggesting that adults and children generate distinct mucosal antibody responses during the acute phase of infection. CONCLUSION: Utilizing respiratory and nonrespiratory PCR testing, along with the measurement of SARS-CoV-2-specific local and systemic antibodies, provides a more accurate assessment of infection within households and highlights some of the immunological differences in response between children and adults.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Anticorpos Antivirais , COVID-19/diagnóstico , Criança , Humanos , Imunoglobulina A
8.
Emerg Infect Dis ; 27(10): 2521-2528, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34545796

RESUMO

As of March 2021, coronavirus disease (COVID-19) had led to >500,000 deaths in the United States, and the state of Tennessee had the fifth highest number of cases per capita. We reviewed the Tennessee Department of Health COVID-19 surveillance and chart-abstraction data during March 15‒August 15, 2020. Patients who died from COVID-19 were more likely to be older, male, and Black and to have underlying conditions (hereafter comorbidities) than case-patients who survived. We found 30.4% of surviving case-patients and 20.3% of deceased patients had no comorbidity information recorded. Chart-abstraction captured a higher proportion of deceased case-patients with >1 comorbidity (96.3%) compared with standard surveillance deaths (79.0%). Chart-abstraction detected higher rates of each comorbidity except for diabetes, which had similar rates among standard surveillance and chart-abstraction. Investing in public health data collection infrastructure will be beneficial for the COVID-19 pandemic and future disease outbreaks.


Assuntos
COVID-19 , Pandemias , Comorbidade , Hospitalização , Humanos , Masculino , Estudos Retrospectivos , SARS-CoV-2 , Tennessee/epidemiologia , Estados Unidos/epidemiologia
9.
AIDS Res Ther ; 17(1): 65, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33168019

RESUMO

BACKGROUND: Analytical treatment interruptions (ATI) are commonly used clinical endpoints to assess interventions aimed at curing HIV or achieving antiretroviral therapy (ART)-free HIV remission. Understanding the acceptability of ATI amongst people living with HIV (PLHIV) and their HIV healthcare providers (HHP) is limited. METHODS: Two online surveys for PLHIV and HHP assessed awareness and acceptability of ATI, and understanding of the prospect for HIV cure in the future. Responses were collected from July 2017-January 2018. A descriptive analysis was performed and similar questions across the two surveys were compared using χ squared test. RESULTS: 442 PLHIV and 144 HHP completed the survey. 105/400 (26%) PLHIV had ever interrupted ART, 8% of which were in a clinical trial. Altruistic motivations were drivers of participation of PLHIV in cure related research. 81/135 (60%) HHP would support their patients wishing to enrol in an HIV cure-focused trial, but fewer would promote and allow such participation (25% and 31% respectively). Compared to HHP, PLHIV were more likely to believe that an HIV cure would be achievable within 10 years (55% vs. 19%, p < 0.001), had less awareness of ATI (46% vs. 62%, p < 0.001) and were less likely to have had experience of either participation or enrolment in an ATI study (5% vs. 18%, p < 0.001) CONCLUSION: PLHIV were more optimistic about the potential for HIV cure. HHP had more direct experience with HIV cure-focused studies. Educational strategies are required for both groups to increase understanding around ATIs in HIV cure research but should be tailored specifically to each group.


Assuntos
Infecções por HIV , Motivação , Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Pessoal de Saúde , Humanos , Inquéritos e Questionários
10.
Microb Cell Fact ; 18(1): 117, 2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31255171

RESUMO

BACKGROUND: Rhodosporidium toruloides is a promising host for the production of bioproducts from lignocellulosic biomass. A key prerequisite for efficient pathway engineering is the availability of robust genetic tools and resources. However, there is a lack of characterized promoters to drive expression of heterologous genes for strain engineering in R. toruloides. RESULTS: This data describes a set of native R. toruloides promoters, characterized over time in four different media commonly used for cultivation of this yeast. The promoter sequences were selected using transcriptional analysis and several of them were found to drive expression bidirectionally. Promoter expression strength was determined by measurement of EGFP and mRuby2 reporters by flow cytometry. A total of 20 constitutive promoters (12 monodirectional and 8 bidirectional) were found, and are expected to be of potential value for genetic engineering of R. toruloides. CONCLUSIONS: A set of robust and constitutive promoters to facilitate genetic engineering of R. toruloides is presented here, ranging from a promoter previously used for this purpose (P7, glyceraldehyde 3-phosphate dehydrogenase, GAPDH) to stronger monodirectional (e.g., P15, mitochondrial adenine nucleotide translocator, ANT) and bidirectional (e.g., P9 and P9R, histones H3 and H4, respectively) promoters. We also identified promoters that may be useful for specific applications such as late-stage expression (e.g., P3, voltage-dependent anion channel protein 2, VDAC2). This set of characterized promoters significantly expands the range of engineering tools available for this yeast and can be applied in future metabolic engineering studies.


Assuntos
Engenharia Metabólica , Regiões Promotoras Genéticas , Rhodotorula/genética , Sequência de Bases , Rhodotorula/metabolismo , Transformação Genética
12.
PLoS Pathog ; 10(10): e1004473, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25393648

RESUMO

UNLABELLED: Human immunodeficiency virus (HIV) persistence in latently infected resting memory CD4+ T-cells is the major barrier to HIV cure. Cellular histone deacetylases (HDACs) are important in maintaining HIV latency and histone deacetylase inhibitors (HDACi) may reverse latency by activating HIV transcription from latently infected CD4+ T-cells. We performed a single arm, open label, proof-of-concept study in which vorinostat, a pan-HDACi, was administered 400 mg orally once daily for 14 days to 20 HIV-infected individuals on suppressive antiretroviral therapy (ART). The primary endpoint was change in cell associated unspliced (CA-US) HIV RNA in total CD4+ T-cells from blood at day 14. The study is registered at ClinicalTrials.gov (NCT01365065). Vorinostat was safe and well tolerated and there were no dose modifications or study drug discontinuations. CA-US HIV RNA in blood increased significantly in 18/20 patients (90%) with a median fold change from baseline to peak value of 7.4 (IQR 3.4, 9.1). CA-US RNA was significantly elevated 8 hours post drug and remained elevated 70 days after last dose. Significant early changes in expression of genes associated with chromatin remodeling and activation of HIV transcription correlated with the magnitude of increased CA-US HIV RNA. There were no statistically significant changes in plasma HIV RNA, concentration of HIV DNA, integrated DNA, inducible virus in CD4+ T-cells or markers of T-cell activation. Vorinostat induced a significant and sustained increase in HIV transcription from latency in the majority of HIV-infected patients. However, additional interventions will be needed to efficiently induce virus production and ultimately eliminate latently infected cells. TRIAL REGISTRATION: ClinicalTrials.gov NCT01365065.


Assuntos
Linfócitos T CD4-Positivos/virologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Inibidores de Histona Desacetilases/uso terapêutico , Ácidos Hidroxâmicos/uso terapêutico , Ativação Viral/efeitos dos fármacos , Adulto , Linfócitos T CD4-Positivos/imunologia , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , HIV-1/fisiologia , Humanos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , RNA Viral/genética , Transcrição Gênica/efeitos dos fármacos , Latência Viral/efeitos dos fármacos , Vorinostat
13.
J Immunol ; 192(4): 1732-44, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24446519

RESUMO

Hyperactivation of T cells, particularly of CD8(+) T cells, is a hallmark of chronic HIV 1 (HIV-1) infection. Little is known about the antigenic specificities and the mechanisms by which HIV-1 causes activation of CD8(+) T cells during chronic infection. We report that CD8(+) T cells were activated during in vivo HIV-1 replication irrespective of their Ag specificity. Cytokines present during untreated HIV-1 infection, most prominently IL-15, triggered proliferation and expression of activation markers in CD8(+) T cells, but not CD4(+) T cells, in the absence of TCR stimulation. Moreover, LPS or HIV-1-activated dendritic cells (DCs) stimulated CD8(+) T cells in an IL-15-dependent but Ag-independent manner, and IL-15 expression was highly increased in DCs isolated from viremic HIV-1 patients, suggesting that CD8(+) T cells are activated by inflammatory cytokines in untreated HIV-1 patients independent of Ag specificity. This finding contrasts with CD4(+) T cells whose in vivo activation seems biased toward specificities for persistent Ags. These observations explain the higher abundance of activated CD8(+) T cells compared with CD4(+) T cells in untreated HIV-1 infection.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Interleucina-15/metabolismo , Ativação Linfocitária/imunologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células , Células Dendríticas/imunologia , Feminino , Infecções por HIV/tratamento farmacológico , HIV-1/imunologia , Humanos , Lipopolissacarídeos , Masculino , Pessoa de Meia-Idade
14.
Angew Chem Int Ed Engl ; 53(25): 6397-401, 2014 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-24827541

RESUMO

Combining quantum-mechanical simulations and synthesis tools allows the design of highly efficient CuCo/MoO(x) catalysts for the selective conversion of synthesis gas (CO+H2) into ethanol and higher alcohols, which are of eminent interest for the production of platform chemicals from non-petroleum feedstocks. Density functional theory calculations coupled to microkinetic models identify mixed Cu-Co alloy sites, at Co-enriched surfaces, as ideal for the selective production of long-chain alcohols. Accordingly, a versatile synthesis route is developed based on metal nanoparticle exsolution from a molybdate precursor compound whose crystalline structure isomorphically accommodates Cu(2+) and Co(2+) cations in a wide range of compositions. As revealed by energy-dispersive X-ray nanospectroscopy and temperature-resolved X-ray diffraction, superior mixing of Cu and Co species promotes formation of CuCo alloy nanocrystals after activation, leading to two orders of magnitude higher yield to high alcohols than a benchmark CuCoCr catalyst. Substantiating simulations, the yield to high alcohols is maximized in parallel to the CuCo alloy contribution, for Co-rich surface compositions, for which Cu phase segregation is prevented.

15.
Front Microbiol ; 15: 1355444, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725686

RESUMO

The aerobic hyperthermophile "Fervidibacter sacchari" catabolizes diverse polysaccharides and is the only cultivated member of the class "Fervidibacteria" within the phylum Armatimonadota. It encodes 117 putative glycoside hydrolases (GHs), including two from GH family 50 (GH50). In this study, we expressed, purified, and functionally characterized one of these GH50 enzymes, Fsa16295Glu. We show that Fsa16295Glu is a ß-1,3-endoglucanase with optimal activity on carboxymethyl curdlan (CM-curdlan) and only weak agarase activity, despite most GH50 enzymes being described as ß-agarases. The purified enzyme has a wide temperature range of 4-95°C (optimal 80°C), making it the first characterized hyperthermophilic representative of GH50. The enzyme is also active at a broad pH range of at least 5.5-11 (optimal 6.5-10). Fsa16295Glu possesses a relatively high kcat/KM of 1.82 × 107 s-1 M-1 with CM-curdlan and degrades CM-curdlan nearly completely to sugar monomers, indicating preferential hydrolysis of glucans containing ß-1,3 linkages. Finally, a phylogenetic analysis of Fsa16295Glu and all other GH50 enzymes revealed that Fsa16295Glu is distant from other characterized enzymes but phylogenetically related to enzymes from thermophilic archaea that were likely acquired horizontally from "Fervidibacteria." Given its functional and phylogenetic novelty, we propose that Fsa16295Glu represents a new enzyme subfamily, GH50_3.

16.
Microbiol Resour Announc ; 13(2): e0108023, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38189307

RESUMO

We present eight metatranscriptomic datasets of light algal and cyanolichen biological soil crusts from the Mojave Desert in response to wetting. These data will help us understand gene expression patterns in desert biocrust microbial communities after they have been reactivated by the addition of water.

17.
Microbiol Resour Announc ; 13(3): e0098023, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38329355

RESUMO

We present six whole community shotgun metagenomic sequencing data sets of two types of biological soil crusts sampled at the ecotone of the Mojave Desert and Colorado Desert in California. These data will help us understand the diversity and function of biocrust microbial communities, which are essential for desert ecosystems.

18.
bioRxiv ; 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38915524

RESUMO

Engineering the genetic code of an organism provides the basis for (i) making any organism safely resistant to natural viruses and (ii) preventing genetic information flow into and out of genetically modified organisms while (iii) allowing the biosynthesis of genetically encoded unnatural polymers1-4. Achieving these three goals requires the reassignment of multiple of the 64 codons nature uses to encode proteins. However, synonymous codon replacement-recoding-is frequently lethal, and how recoding impacts fitness remains poorly explored. Here, we explore these effects using whole-genome synthesis, multiplexed directed evolution, and genome-transcriptome-translatome-proteome co-profiling on multiple recoded genomes. Using this information, we assemble a synthetic Escherichia coli genome in seven sections using only 57 codons to encode proteins. By discovering the rules responsible for the lethality of synonymous recoding and developing a data-driven multi-omics-based genome construction workflow that troubleshoots synthetic genomes, we overcome the lethal effects of 62,007 synonymous codon swaps and 11,108 additional genomic edits. We show that synonymous recoding induces transcriptional noise including new antisense RNAs, leading to drastic transcriptome and proteome perturbation. As the elimination of select codons from an organism's genetic code results in the widespread appearance of cryptic promoters, we show that synonymous codon choice may naturally evolve to minimize transcriptional noise. Our work provides the first genome-scale description of how synonymous codon changes influence organismal fitness and paves the way for the construction of functional genomes that provide genetic firewalls from natural ecosystems and safely produce biopolymers, drugs, and enzymes with an expanded chemistry.

19.
BMC Infect Dis ; 13: 100, 2013 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-23442890

RESUMO

BACKGROUND: HIV infection induces chronic immune activation which is associated with accelerated disease progression; the causes of this activation, however, are incompletely understood. We investigated the activation status of CD4+ T cells specific for chronic herpes viruses and the non-persistent antigen tetanus toxoid (TT) in HIV positive and HIV negative donors to assess whether persistent infections contribute to chronic CD4+ T cell activation. METHODS: Untreated HIV+ patients and healthy, aged matched controls were recruited and activation levels assessed and compared between cells specific for persistent and non-persistent antigens. Activation levels on antigen-specific CD4+ T cells were measured by intracellular cytokine staining following in vitro stimulation with various recall antigens (CMV, EBV, HSV, VZV and TT) in conjunction with cell surface phenotyping. RESULTS: Activation levels of herpes virus-specific CD4+ T cell populations, assessed by co-expression of CD38 and HLA-DR, were significantly elevated in HIV+ individuals compared to normal controls and compared to TT-specific responses. In contrast, we found similar levels of activation of TT-specific CD4+ T cells in HIV+ and HIV- donors. CONCLUSIONS: These results show a disparate distribution of immune activation within CD4+ T cell populations depending on their specificity and suggest that the elevated level of immune activation that characterizes chronic HIV infection may be influenced by the persistence of other antigens.


Assuntos
Antígenos Virais/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , ADP-Ribosil Ciclase 1/imunologia , Adulto , Alphaherpesvirinae/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Doença Crônica , Feminino , Citometria de Fluxo , Antígenos HLA-DR/metabolismo , Humanos , Cadeias beta de Integrinas/imunologia , Ativação Linfocitária/imunologia , Masculino , Glicoproteínas de Membrana/imunologia , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/imunologia
20.
J Nurses Prof Dev ; 39(4): E44-E49, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34772835

RESUMO

Current literature supports the creation and implementation of nurse residency programs to support new graduate nurses. The lack of this important postlicensure resource poses a problem for new graduate nurses who are seeking additional assistance and guidance during the transition to professional practice. This qualitative study revealed the factors, barriers, and benefits that influenced the decision-making process of nurse leaders in the implementation of nurse residency programs.


Assuntos
Administradores Hospitalares , Internato e Residência , Humanos , Pesquisa Qualitativa , Liderança
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA