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1.
Immunity ; 54(11): 2465-2480.e5, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34706222

RESUMO

Epigenetic reprogramming underlies specification of immune cell lineages, but patterns that uniquely define immune cell types and the mechanisms by which they are established remain unclear. Here, we identified lineage-specific DNA methylation signatures of six immune cell types from human peripheral blood and determined their relationship to other epigenetic and transcriptomic patterns. Sites of lineage-specific hypomethylation were associated with distinct combinations of transcription factors in each cell type. By contrast, sites of lineage-specific hypermethylation were restricted mostly to adaptive immune cells. PU.1 binding sites were associated with lineage-specific hypo- and hypermethylation in different cell types, suggesting that it regulates DNA methylation in a context-dependent manner. These observations indicate that innate and adaptive immune lineages are specified by distinct epigenetic mechanisms via combinatorial and context-dependent use of key transcription factors. The cell-specific epigenomics and transcriptional patterns identified serve as a foundation for future studies on immune dysregulation in diseases and aging.


Assuntos
Metilação de DNA , Epigênese Genética , Epigenômica , Regulação da Expressão Gênica , Imunidade , Fatores de Transcrição/metabolismo , Transcriptoma , Epigenômica/métodos , Humanos , Sistema Imunitário/citologia , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Fatores de Transcrição/genética
3.
Mol Cell ; 70(1): 21-33.e6, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29576529

RESUMO

Immunoglobulin heavy-chain (IgH) genes are assembled by DNA rearrangements that juxtapose a variable (VH), a diversity (DH), and a joining (JH) gene segment. Here, we report that in the absence of intergenic control region 1 (IGCR1), the intronic enhancer (Eµ) associates with the next available CTCF binding site located close to VH81X via putative heterotypic interactions involving YY1 and CTCF. The alternate Eµ/VH81X loop leads to formation of a distorted recombination center and altered DH rearrangements and disrupts chromosome conformation that favors distal VH recombination. Cumulatively, these features drive highly skewed, Eµ-dependent recombination of VH81X. Sequential deletion of CTCF binding regions on IGCR1-deleted alleles suggests that they influence recombination of single proximal VH gene segments. Our observations demonstrate that Eµ interacts differently with IGCR1- or VH-associated CTCF binding sites and thereby identify distinct roles for insulator-like elements in directing enhancer activity.


Assuntos
Montagem e Desmontagem da Cromatina , DNA Intergênico/genética , Elementos Facilitadores Genéticos , Genes de Cadeia Pesada de Imunoglobulina , Loci Gênicos , Região Variável de Imunoglobulina/genética , Células Precursoras de Linfócitos B/metabolismo , Recombinação Genética , Animais , Sítios de Ligação , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Linhagem Celular , DNA Intergênico/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Região Variável de Imunoglobulina/imunologia , Região Variável de Imunoglobulina/metabolismo , Camundongos da Linhagem 129 , Camundongos Knockout , Conformação de Ácido Nucleico , Células Precursoras de Linfócitos B/imunologia , Fator de Transcrição YY1/genética , Fator de Transcrição YY1/metabolismo
4.
PLoS Genet ; 18(11): e1010506, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36441670

RESUMO

Short telomeres induce a DNA damage response (DDR) that evokes apoptosis and senescence in human cells. An extant question is the contribution of telomere dysfunction-induced DDR to the phenotypes observed in aging and telomere biology disorders. One candidate is RAP1, a telomere-associated protein that also controls transcription at extratelomeric regions. To distinguish these roles, we generated a knockin mouse carrying a mutated Rap1, which was incapable of binding telomeres and did not result in eroded telomeres or a DDR. Primary Rap1 knockin embryonic fibroblasts showed decreased RAP1 expression and re-localization away from telomeres, with an increased cytosolic distribution akin to that observed in human fibroblasts undergoing telomere erosion. Rap1 knockin mice were viable, but exhibited transcriptomic alterations, proinflammatory cytokine/chemokine signaling, reduced lifespan, and decreased healthspan with increased body weight/fasting blood glucose levels, spontaneous tumor incidence, and behavioral deficits. Taken together, our data present mechanisms distinct from telomere-induced DDR that underlie age-related phenotypes.


Assuntos
Complexo Shelterina , Telômero , Animais , Humanos , Camundongos , Longevidade , Fenótipo , Telômero/genética , Encurtamento do Telômero
5.
J Neurosci ; 43(14): 2579-2596, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36859308

RESUMO

Many social animals can recognize other individuals by their vocalizations. This requires a memory system capable of mapping incoming acoustic signals to one of many known individuals. Using the zebra finch, a social songbird that uses songs and distance calls to communicate individual identity (Elie and Theunissen, 2018), we tested the role of two cortical-like brain regions in a vocal recognition task. We found that the rostral region of the Cadomedial Nidopallium (NCM), a secondary auditory region of the avian pallium, was necessary for maintaining auditory memories for conspecific vocalizations in both male and female birds, whereas HVC (used as a proper name), a premotor areas that gates auditory input into the vocal motor and song learning pathways in male birds (Roberts and Mooney, 2013), was not. Both NCM and HVC have previously been implicated for processing the tutor song in the context of song learning (Sakata and Yazaki-Sugiyama, 2020). Our results suggest that NCM might not only store songs as templates for future vocal imitation but also songs and calls for perceptual discrimination of vocalizers in both male and female birds. NCM could therefore operate as a site for auditory memories for vocalizations used in various facets of communication. We also observed that new auditory memories could be acquired without intact HVC or NCM but that for these new memories NCM lesions caused deficits in either memory capacity or auditory discrimination. These results suggest that the high-capacity memory functions of the avian pallial auditory system depend on NCM.SIGNIFICANCE STATEMENT Many aspects of vocal communication require the formation of auditory memories. Voice recognition, for example, requires a memory for vocalizers to identify acoustical features. In both birds and primates, the locus and neural correlates of these high-level memories remain poorly described. Previous work suggests that this memory formation is mediated by high-level sensory areas, not traditional memory areas such as the hippocampus. Using lesion experiments, we show that one secondary auditory brain region in songbirds that had previously been implicated in storing song memories for vocal imitation is also implicated in storing vocal memories for individual recognition. The role of the neural circuits in this region in interpreting the meaning of communication calls should be investigated in the future.


Assuntos
Tentilhões , Vocalização Animal , Animais , Masculino , Feminino , Estimulação Acústica , Aprendizagem , Encéfalo , Percepção Auditiva
6.
Oncologist ; 29(2): e237-e247, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37756655

RESUMO

BACKGROUND: With the COVID-19 pandemic came rapid uptake in virtual oncology care. During this, sociodemographic inequities in access to virtual visits (VVs) have become apparent. To better understand these issues, we conducted a qualitative study to describe the perceived usability and acceptability of VVs among Black adults diagnosed with cancer. METHODS: Adults who self-identified as Black and had a diagnosis of prostate, multiple myeloma, or head and neck cancer were recruited from 2 academic medical centers, and their community affiliates to participate in a semi-structured interview, regardless of prior VV experience. A patient and family advisory board was formed to inform all components of the study. Interviews were conducted between September 2, 2021 and February 23, 2022. Transcripts were organized topically, and themes and subthemes were determined through iterative and interpretive immersion/crystallization cycles. RESULTS: Of the 49 adults interviewed, 29 (59%) had participated in at least one VV. Three overarching themes were derived: (1) VVs felt comfortable and convenient in the right contexts; (2) the technology required for VVs with video presented new challenges, which were often resolved by an audio-only telephone call; and (3) participants reported preferring in-person visits, citing concerns regarding gaps in nonverbal communication, trusting providers, and distractions during VV. CONCLUSION: While VVs were reported to be acceptable in specific circumstances, Black adults reported preferring in-person care, in part due to a perceived lack of interpersonal connectedness. Nonetheless, retaining reimbursement for audio-only options for VVs is essential to ensure equitable access for those with less technology savvy and/or limited device/internet capabilities.


Assuntos
COVID-19 , Pandemias , Adulto , Masculino , Humanos , Oncologia , Centros Médicos Acadêmicos , COVID-19/epidemiologia , Internet
7.
Oncologist ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828490

RESUMO

INTRODUCTION: Standard investigator-based adverse events (AE) assessment is via CTCAE for clinical trials. However, including the patient perspective through PRO (patient-reported outcomes) enhances clinicians' understanding of patient toxicity and fosters early detection of AEs. We assessed longitudinal integration of PRO-CTCAE within clinical workflow in a phase II trial. MATERIALS AND METHODS: As a sub-study in a phase II trial of genotype-directed irinotecan dosing evaluating efficacy in patients with metastatic colorectal cancer receiving FOLFIRI and bevacizumab, patients reported on 13 AEs generating a PRO-CTCAE form. The primary objective was to estimate forms completed by patients and clinicians at least 80% of time. Secondary objectives were estimating concordance and time to first score of specific symptoms between patient and clinician pairs. RESULTS: Feasibility of longitudinal PRO-CTCAE integration was met as 96% of patients and clinician-patient pairs completed at least 80% of PRO-CTCAE forms available to them with 79% achieving 100% completion. Concordance between patient and clinician reporting a severe symptom was 73% with 24 disconcordant pairs, 21 involved patients who reported a severe symptom that the clinician did not. Although protocol-mandated dose reductions were guided by CTCAE not PRO-CTCAE responses, the median time to dose reduction of 2.53 months, and the time-to-event curve closely approximated time to patient-reported toxicity. CONCLUSION: Longitudinal integration of PRO-CTCAE paired CTCAE proved feasible. Compared to clinicians, patients reported severe symptoms more frequently and earlier. Patient-reported toxicity more closely aligned with dose decreases indicating incorporation into routine clinical practice may enhance early detection of toxicity improving patient safety and quality of life.

8.
Oncologist ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837045

RESUMO

BACKGROUND: FOLFIRI is a standard regimen for metastatic colorectal cancer (mCRC). We hypothesized that a pharmacogenomic-directed strategy where more efficient irinotecan metabolizers (UGT1A1 *1/*1 homozygotes and *1/*28 heterozygotes) receive higher-than-standard irinotecan doses would improve progression-free survival (PFS) compared to non-genotype selected historical controls with acceptable toxicity. METHODS: In this phase II multicenter study irinotecan dosing in first-line FOLFIRI and bevacizumab for mCRC was based on UGT1A1 genotype with *1/*1, *1/*28, and *28/*28 patients receiving 310 mg/m2, 260 mg/m2, and 180 mg/m2, respectively. Primary endpoint was PFS. Secondary endpoints were investigator and patient-reported adverse events, and estimation of overall survival (OS). RESULTS: One-hundred patients were enrolled with 91 evaluable for PFS and 83 evaluable for best response. Median PFS was 12.5 months (90% CI 10.9, 15.4), shorter than the anticipated alternative hypothesis of 14 months. PFS by genotype was 12.5 months (90% CI 10.9, 17.4) for *1/*1, 14.6 months (90% CI 11.8, 17.5) for *1/*28, and 6 months (90% CI 2.3, 7.7) for *28/28, respectively. OS was 24.5 months (90% CI 19.1, 30.7) and by genotype was 26.5 (90% CI 19.1, 32.9), 25.9 (90% CI 17.6, 37.7), and 13.4 (90% CI 2.3, 20.5) months for *1/*1, *1/*28, and *28/*28, respectively. G3/4 toxicity was similar between all subgroups, including diarrhea and neutropenia. CONCLUSIONS: A pharmacogenomic-directed irinotecan strategy improved PFS in the *1/*1 and *1/*28 genotypes with higher rates of neutropenia and similar rates of diarrhea compared to expected with standard FOLFIRI dosing. However, improvements in response rate and PFS were modest. This strategy should not change standard practice for mCRC patients in the first-line setting.

9.
Nat Mater ; 22(2): 216-224, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36702888

RESUMO

Investigation of the inherent field-driven charge transport behaviour of three-dimensional lead halide perovskites has largely remained challenging, owing to undesirable ionic migration effects near room temperature and dipolar disorder instabilities prevalent specifically in methylammonium-and-lead-based high-performing three-dimensional perovskite compositions. Here, we address both these challenges and demonstrate that field-effect transistors based on methylammonium-free, mixed metal (Pb/Sn) perovskite compositions do not suffer from ion migration effects as notably as their pure-Pb counterparts and reliably exhibit hysteresis-free p-type transport with a mobility reaching 5.4 cm2 V-1 s-1. The reduced ion migration is visualized through photoluminescence microscopy under bias and is manifested as an activated temperature dependence of the field-effect mobility with a low activation energy (~48 meV) consistent with the presence of the shallow defects present in these materials. An understanding of the long-range electronic charge transport in these inherently doped mixed metal halide perovskites will contribute immensely towards high-performance optoelectronic devices.

10.
Support Care Cancer ; 32(3): 197, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416230

RESUMO

PURPOSE: Treatment decision-making for older adults with acute myeloid leukemia (AML) is complex and preference-sensitive. We sought to understand the patient experience of treatment decision-making to identify specific challenges in shared decision-making to improve clinical care and to inform the development of directed interventions. METHODS: We conducted in-depth interviews with newly diagnosed older (≥ 60 years) adults with AML and their caregivers following a semi-structured interview guide at a public safety net academic hospital. Interviews were digitally recorded, and qualitative thematic analysis was employed to synthesize findings. RESULTS: Eighteen in-depth interviews were conducted. Age ranged from 62 to 78 years. Patients received intermediate- (50%) or high-intensity (44%) chemotherapy or best supportive care only (6%). Six themes of patient experiences emerged from the analysis: patients (1) felt overwhelmed and in shock at diagnosis, (2) felt powerless to make decisions, (3) felt rushed and unprepared to make a treatment decision, (4) desired to follow oncologist recommendations for treatment, (5) balanced multiple competing factors during treatment decision-making, and (6) desired for ongoing engagement into their care planning. Patients reported many treatment outcomes that were important in treatment decision-making. CONCLUSIONS: Older adults with newly diagnosed AML feel devastated and in shock at their diagnosis which appears to contribute to a feeling of being overwhelmed, unprepared, and rushed into treatment decisions. Because no one factor dominated treatment decision-making for all patients, the use of strategies to elicit individual patient preferences is critical to inform treatment decisions. Interventions are needed to reduce distress and increase a sense of participation in treatment decision-making.


Assuntos
Leucemia Mieloide Aguda , Oncologistas , Humanos , Idoso , Pessoa de Meia-Idade , Leucemia Mieloide Aguda/terapia , Tomada de Decisão Compartilhada , Emoções , Preferência do Paciente
11.
Blood ; 137(4): 556-568, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33104215

RESUMO

Social determinants of health, including poverty, contribute significantly to health outcomes in the United States; however, their impact on pediatric hematopoietic cell transplantation (HCT) outcomes is poorly understood. We aimed to identify the association between neighborhood poverty and HCT outcomes for pediatric allogeneic HCT recipients in the Center for International Blood and Marrow Transplant Research database. We assembled 2 pediatric cohorts undergoing first allogeneic HCT from 2006 to 2015 at age ≤18 years, including 2053 children with malignant disease and 1696 children with nonmalignant disease. Neighborhood poverty exposure was defined a priori per the US Census definition as living in a high-poverty ZIP code (≥20% of persons below 100% federal poverty level) and used as the primary predictor in all analyses. Our primary outcome was overall survival (OS), defined as the time from HCT until death resulting from any cause. Secondary outcomes included relapse and transplantation-related mortality (TRM) in malignant disease, acute and chronic graft-versus-host disease, and infection in the first 100 days post-HCT. Among children undergoing transplantation for nonmalignant disease, neighborhood poverty was not associated with any HCT outcome. Among children undergoing transplantation for malignant disease, neighborhood poverty conferred an increased risk of TRM but was not associated with inferior OS or any other transplantation outcome. Among children with malignant disease, a key secondary finding was that children with Medicaid insurance experienced inferior OS and increased TRM compared with those with private insurance. These data suggest opportunities for future investigation of the effects of household-level poverty exposure on HCT outcomes in pediatric malignant disease to inform care delivery interventions.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Pobreza , Determinantes Sociais da Saúde , Adolescente , Causas de Morte , Criança , Pré-Escolar , Doença Crônica/mortalidade , Doença Crônica/terapia , Bases de Dados Factuais , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/economia , Transplante de Células-Tronco Hematopoéticas/mortalidade , Transplante de Células-Tronco Hematopoéticas/estatística & dados numéricos , Humanos , Lactente , Infecções/epidemiologia , Cobertura do Seguro/estatística & dados numéricos , Masculino , Medicaid , Neoplasias/mortalidade , Neoplasias/terapia , Recidiva , Análise de Sobrevida , Transplante Homólogo , Resultado do Tratamento , Estados Unidos
12.
Support Care Cancer ; 31(3): 196, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36859693

RESUMO

BACKGROUND: This study investigates whether high body mass index (BMI) in women diagnosed with early breast cancer (BC) is associated with patient-reported symptom severity during chemotherapy. METHODS: Women with Stage I-III BC completed toxicity reports for 17 side effects throughout regularly scheduled chemotherapy infusions. Toxicity reports were compared in women with obesity (BMI > = 30) versus no obesity (BMI < 30). Fisher's exact tests and 2-sample t-tests compared baseline patient characteristics. Risk ratios (RR) for women with obesity as compared to no obesity were estimated for individual symptoms that were patient-rated as moderate, severe or very severe (MSVS) severity, adjusting for marital status and race. RESULTS: In a sample of 286 patients, Black women comprised 23% of the sample. The obesity rate was 76% among Black patients and 31% among White patients (p < .0001). Women with obesity rated an average of 6.9 side effects (standard deviation, SD 4.2) as MSVS vs 5.5 side effects (SD 3.7) among women with no obesity (p = .003). In adjusted analysis, women with obesity had significantly greater risk for MSVS fatigue (RR 1.18, 95% CI 1.01-1.36), dyspnea (RR 1.71, 95% CI 1.09-2.69), arthralgia (RR 1.47, 95% CI 1.10-1.97), peripheral neuropathy (RR 1.45, 95% CI 1.01-2.08), edema of limbs (RR 1.84, 95% CI 1.18-2.88), and abdominal pain (RR 1.75, 95% CI 1.07-2.87). There were no inter-group differences in BC stage or phenotype, chemotherapy treatment modifications, or hospitalizations. CONCLUSIONS: Among women with early BC, patients with obesity reported higher chemotherapy toxicity as compared to patients without obesity; however, this did not result in differences in treatment completion.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Neoplasias , Feminino , Humanos , Masculino , Índice de Massa Corporal , Qualidade de Vida , Quimioterapia Adjuvante , Obesidade , Medidas de Resultados Relatados pelo Paciente
13.
Support Care Cancer ; 32(1): 68, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38153568

RESUMO

BACKGROUND: In the field of exercise oncology, there is a need to quantify the potential benefits of moderate, self-directed physical activity during active treatment. In a pooled analysis of three identical single-arm intervention studies, we investigate the association of activity tracker steps with patient-reported toxicities during chemotherapy. METHODS: Women with early breast cancer who were enrolled in the intervention studies reported their symptom severity every 2-3 weeks throughout chemotherapy, and daily steps were documented through a Fitbit activity tracker. Relative risks (RR) and 95% confidence intervals (CI) were calculated using Poisson regression models with robust variance. For outcomes significant in unadjusted models, adjusted RRs were calculated controlling for race, age, and education level. Tracker step cut point (high step, low step) was determined by the means. Cumulative incidence functions of moderate, severe, and very severe (MSVS) symptoms were estimated using the Kaplan-Meier method and compared using a Cox proportional hazard model. RESULTS: In a sample of 283 women, mean age was 56 years and 76% were White. Mean tracker-documented steps/week were 29,625, with 55% walking below the mean (low step) and 45% above (high step). In multivariable analysis, high step patients had lower risk for fatigue [RR 0.83 (0.70, 0.99)] (p = 0.04), anxiety [RR 0.59 (0.42, 0.84)] (p = 0.003), nausea [RR 0.66 (0.46, 0.96)] (p = 0.03), depression [RR 0.59 (0.37, 0.03)] (p = 0.02), and ≥ 6 MSVS symptoms [RR 0.73 (0.54, 1.00)] (p = 0.05) and had 36% lower risk for dose reductions [RR 0.64 (95% CI 0.43, 0.97)] (p = 0.03). CONCLUSION: Self-directed walking at a rate of at least 30,000 steps/week may moderate the severity of treatment side effects during chemotherapy for early breast cancer. TRIAL NUMBERS: NCT02167932, NCT02328313, NCT03761706.


Assuntos
Neoplasias da Mama , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Pessoa de Meia-Idade , Ansiedade , Neoplasias da Mama/tratamento farmacológico , Exercício Físico , Caminhada
14.
Annu Rev Cell Dev Biol ; 25: 93-112, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19575638

RESUMO

A growing revolution is under way in the teaching of introductory science to undergraduates. It is driven by concerns about American competitiveness as well as results from recent educational research, which explains why traditional teaching approaches in large classes fail to reach many students and provides a basis for designing improved methods of instruction. Discipline-based educational research in the life sciences and other areas has identified several innovative promising practices and demonstrated their effectiveness for increasing student learning. Their widespread adoption could have a major impact on the introductory training of biology students.


Assuntos
Biologia/educação , Ensino/métodos , Currículo , Aprendizagem , Ciência/educação , Estudantes
15.
J Med Internet Res ; 25: e43404, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36598811

RESUMO

Although health care delivery is becoming increasingly digitized, driven by the pursuit of improved access, equity, efficiency, and effectiveness, progress does not appear to be equally distributed across therapeutic areas. Oncology is renowned for leading innovation in research and in care; digital pathology, digital radiology, real-world data, next-generation sequencing, patient-reported outcomes, and precision approaches driven by complex data and biomarkers are hallmarks of the field. However, remote patient monitoring, decentralized approaches to care and research, "hospital at home," and machine learning techniques have yet to be broadly deployed to improve cancer care. In response, the Digital Medicine Society and Moffitt Cancer Center convened a multistakeholder roundtable discussion to bring together leading experts in cancer care and digital innovation. This viewpoint highlights the findings from these discussions, in which experts agreed that digital innovation is lagging in oncology relative to other therapeutic areas. It reports that this lag is most likely attributed to poor articulation of the challenges in cancer care and research best suited to digital solutions, lack of incentives and support, and missing standardized infrastructure to implement digital innovations. It concludes with suggestions for actions needed to bring the promise of digitization to cancer care to improve lives.


Assuntos
Atenção à Saúde , Neoplasias , Humanos , Atenção à Saúde/métodos , Neoplasias/terapia , Medidas de Resultados Relatados pelo Paciente
16.
Genes Dev ; 29(15): 1599-604, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26253535

RESUMO

Eukaryotic gene expression is tightly regulated post-transcriptionally by RNA-binding proteins (RBPs) and microRNAs. The RBP AU-rich-binding factor 1 (AUF1) isoform p37 was found to have high affinity for the microRNA let-7b in vitro (Kd = ∼ 6 nM) in cells. Ribonucleoprotein immunoprecipitation, in vitro association, and single-molecule-binding analyses revealed that AUF1 promoted let-7b loading onto Argonaute 2 (AGO2), the catalytic component of the RNA-induced silencing complex (RISC). In turn, AGO2-let-7 triggered target mRNA decay. Our findings uncover a novel mechanism by which AUF1 binding and transfer of microRNA let-7 to AGO2 facilitates let-7-elicited gene silencing.


Assuntos
Proteínas Argonautas/metabolismo , Inativação Gênica/fisiologia , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/metabolismo , MicroRNAs/metabolismo , Animais , Células Cultivadas , Células HeLa , Ribonucleoproteína Nuclear Heterogênea D0 , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/genética , Humanos , Camundongos , Ligação Proteica , Estabilidade de RNA/fisiologia
17.
J Psychosoc Oncol ; 41(3): 321-336, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35959854

RESUMO

PURPOSE: To describe caregiver psychological processing during the 12 weeks after transplant and the potential role of positive emotions in caregiving experiences. METHODS: We conducted a longitudinal qualitative descriptive study and interviewed 11 BMT caregivers monthly for 12-weeks post-transplant about their experiences and psychological processing. We analyzed 38 interviews using directed content analysis based on guiding theories and inductive in vivo coding to develop themes. RESULTS: The majority of participants appraised caregiving as a challenge that needed to be met. Caregivers described feeling positive emotions throughout the time after transplant (gratitude, interest, and hope). We identified two new themes: mirroring (caregiver feelings reflecting patient status) and emotion regulation (hiding negative emotions and displaying positive emotions when with the patient). IMPLICATIONS: Findings provide further evidence that interventions focused on emotion regulation and positive emotion experiences during caregiving to reduce the negative effects of caregiving related stress may be promising.


Assuntos
Transplante de Medula Óssea , Transplante de Células-Tronco Hematopoéticas , Humanos , Cuidadores/psicologia , Estudos Longitudinais , Emoções , Adaptação Psicológica , Pesquisa Qualitativa , Estresse Psicológico/psicologia
18.
Plant J ; 105(1): 223-244, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33118270

RESUMO

Photosynthetic acclimation, the ability to adjust the composition of the thylakoid membrane to optimise the efficiency of electron transfer to the prevailing light conditions, is crucial to plant fitness in the field. While much is known about photosynthetic acclimation in Arabidopsis, to date there has been no study that combines both quantitative label-free proteomics and photosynthetic analysis by gas exchange, chlorophyll fluorescence and P700 absorption spectroscopy. Using these methods we investigated how the levels of 402 thylakoid proteins, including many regulatory proteins not previously quantified, varied upon long-term (weeks) acclimation of Arabidopsis to low (LL), moderate (ML) and high (HL) growth light intensity and correlated these with key photosynthetic parameters. We show that changes in the relative abundance of cytb6 f, ATP synthase, FNR2, TIC62 and PGR6 positively correlate with changes in estimated PSII electron transfer rate and CO2 assimilation. Improved photosynthetic capacity in HL grown plants is paralleled by increased cyclic electron transport, which positively correlated with NDH, PGRL1, FNR1, FNR2 and TIC62, although not PGR5 abundance. The photoprotective acclimation strategy was also contrasting, with LL plants favouring slowly reversible non-photochemical quenching (qI), which positively correlated with LCNP, while HL plants favoured rapidly reversible quenching (qE), which positively correlated with PSBS. The long-term adjustment of thylakoid membrane grana diameter positively correlated with LHCII levels, while grana stacking negatively correlated with CURT1 and RIQ protein abundance. The data provide insights into how Arabidopsis tunes photosynthetic electron transfer and its regulation during developmental acclimation to light intensity.


Assuntos
Aclimatação , Arabidopsis/efeitos da radiação , Proteoma/efeitos da radiação , Tilacoides/efeitos da radiação , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Dióxido de Carbono/metabolismo , Clorofila/metabolismo , Transporte de Elétrons , Luz/efeitos adversos , Espectrometria de Massas , Fotossíntese/efeitos da radiação , Complexo de Proteína do Fotossistema II/metabolismo , Proteoma/metabolismo , Proteoma/fisiologia , Tilacoides/metabolismo , Tilacoides/fisiologia
19.
J Am Chem Soc ; 144(7): 3005-3019, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35157800

RESUMO

Doped organic semiconductors are critical to emerging device applications, including thermoelectrics, bioelectronics, and neuromorphic computing devices. It is commonly assumed that low conductivities in these materials result primarily from charge trapping by the Coulomb potentials of the dopant counterions. Here, we present a combined experimental and theoretical study rebutting this belief. Using a newly developed doping technique based on ion exchange, we prepare highly doped films with several counterions of varying size and shape and characterize their carrier density, electrical conductivity, and paracrystalline disorder. In this uniquely large data set composed of several classes of high-mobility conjugated polymers, each doped with at least five different ions, we find electrical conductivity to be strongly correlated with paracrystalline disorder but poorly correlated with ionic size, suggesting that Coulomb traps do not limit transport. A general model for interacting electrons in highly doped polymers is proposed and carefully parametrized against atomistic calculations, enabling the calculation of electrical conductivity within the framework of transient localization theory. Theoretical calculations are in excellent agreement with experimental data, providing insights into the disorder-limited nature of charge transport and suggesting new strategies to further improve conductivities.

20.
Oncologist ; 27(8): 694-702, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35511734

RESUMO

BACKGROUND: The plasma cell disorders (PCDs), multiple myeloma (MM), and light-chain amyloidosis (AL) are disproportionately diseases of older adults, whose care may be complicated by frailty associated with advancing age. We sought to evaluate the prevalence of functional deficits and symptoms in a cohort of persons with PCDs and associations of demographic, disease-related, functional, and psychosocial measures with quality of life (QoL). PATIENTS AND METHODS: Adults with PCDs were recruited into an observational registry in 2018-2020. Patients completed a functional assessment and European Organization for Research and Treatment of Cancer QoL questionnaire (QLQ-C30). Associations of covariates of interest with QoL were evaluated via univariate linear regression. RESULTS: Among 121 adults, the mean age was 68.6. Diagnoses were 74% MM, 14% AL, 7% both MM and AL, and 5% other PCDs. The median time from diagnosis was 34.9 months. Median lines of therapy were 2, with 11% having received ≥4th-line therapy.Patients with functional deficits had lower mean QoL scores: dependence in IADLs (66.3 vs. 79.9, P = .001) and recent falls (56.7 vs. 76.8, P = .001). Patients ≤6 months from diagnosis had lower QoL (66.7) than those ≥2 years from diagnosis (77.3, P = .03). However, patients on later lines of therapy (≥4th-line) had lower QoL (62.2) than those on 1st-line treatment (76.0, P = .04). CONCLUSIONS: Patients with physical impairments and more advanced PCDs had lower QoL than those without deficits or earlier in their disease course. Early identification of physical impairments may facilitate interventions that mitigate these deficits and thereby improve QoL for patients with PCDs.


Assuntos
Fragilidade , Mieloma Múltiplo , Idoso , Humanos , Mieloma Múltiplo/terapia , Plasmócitos , Qualidade de Vida/psicologia , Inquéritos e Questionários
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