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1.
J Appl Gerontol ; : 7334648241282700, 2024 Sep 18.
Article de Anglais | MEDLINE | ID: mdl-39291724

RÉSUMÉ

Access to home- and community-based services (HCBS) may prevent or delay nursing home transitions among older adults. Medicaid's Balancing Incentive Program (BIP) (2011-2015) provided assistance for U.S. states to increase access to HCBS through infrastructure changes and spending benchmarks. We combined longitudinal data from the 2008-2019 Medicare Current Beneficiary Survey and Minimum Data Set and used survival modeling to examine the association between BIP exposure (living in a BIP-participant state vs. not) and time to long-term institutionalization (LTI, defined as a nursing home episode of 90+ days) among dual enrollees ages 65 and older. In the main effects model, BIP exposure was not associated with hazard of LTI. Interaction models showed that BIP exposure was associated with a lower hazard of LTI among Hispanic/Latinx enrollees, while the opposite was true among non-Hispanic White enrollees. Our findings suggest the outcomes of Medicaid rebalancing efforts may differ across enrollee subgroups.

2.
Alcohol ; 2024 Sep 05.
Article de Anglais | MEDLINE | ID: mdl-39243874

RÉSUMÉ

The unclear mechanisms of ethanol metabolism in the brain highlight the need for a deeper understanding of its metabolic pathways. This study used in vivo microdialysis to simultaneously sample ethanol and its metabolites, acetaldehyde and acetate, in the rat striatum following self-administration of ethanol, emphasizing the natural oral exposure route. To enhance the self-administration, rats underwent two-bottle-choice and limited access training. Dialysate samples, collected every 10 minutes for 2.5 hours, were analyzed using gas chromatography with flame ionization detection (GC-FID). The measured time courses of dialysate concentrations of ethanol, acetaldehyde, and acetate provided insights into dynamics of ethanol metabolism. Notably, in a subject with low ethanol consumption (0.29 g/kg), the concentration of acetaldehyde remained below the limit of detection throughout the experiment. However, the acetate concentration was clearly increased after ethanol consumption in this subject and was comparable to that of other rats with higher ethanol consumption. Compared with focusing only on peak values in the time-courses of concentrations of ethanol and its metabolites, calculating areas under curves provided better models of the relationships between ethanol intake and individual ethanol metabolites, as indicated by the r-square values for the linear regressions. This approach of using the area under the curve accounts for both the amplitude and duration of the concentration profiles, reducing the impact of variations in individual drinking patterns. In vivo microdialysis enables concurrent sampling of brain metabolites during oral ethanol administration, contributing insights into metabolite dynamics. To our knowledge, this paper is the first to report measurement of all three analytes in the brain following self-administration of ethanol. Future studies will explore regional variations and dynamics post-ethanol dependence, further advancing our understanding of ethanol metabolism in the brain.

3.
Res Aging ; : 1640275241269991, 2024 Aug 04.
Article de Anglais | MEDLINE | ID: mdl-39097822

RÉSUMÉ

Recent decades have seen state successes in rebalancing Medicaid long-term care from institutional care (e.g., nursing homes) into home and community settings. However, significant barriers can prevent access to home and community-based services (HCBS) among older adults and persons with dementia. Qualitative research on potential innovations and solutions in the contemporary context with attention to a wider range of state-level policy contexts is limited. Drawing on interviews with 49 key informants including state Medicaid officials, HCBS providers, and advocates for persons with dementia across 11 states, we examined perceived solutions to barriers. Key informants articulated a range of potential solutions and innovations, ranging from tangible or realized policy changes to 'magic wand' solutions. Policy research has typically focused on the former; excluding the latter may miss opportunities to envision and design a more effective long-term care system for persons living with dementia and older adults.

4.
J Appl Gerontol ; : 7334648241270025, 2024 Aug 09.
Article de Anglais | MEDLINE | ID: mdl-39120543

RÉSUMÉ

Over the last several decades, Medicaid has been "rebalancing" services from institutions to the community, increasing support of home- and community-based services (HCBS). These services could potentially substitute for care typically provided by family members, replacing or reducing care from kin. Leveraging one of the most recent Medicaid rebalancing programs, the Balancing Incentive Program (BIP), and using data from the 2008-2016 Health and Retirement Study on 953 Medicaid beneficiaries ages 65 and over with at least one functional limitation, we examined the relationship between exposure to BIP and family and professional caregiving. BIP exposure was not associated with receipt of care or total hours of care. It was, however, associated with more hours of professional care and fewer hours of family care from non-spouse kin. These findings suggest that recent Medicaid rebalancing programs, while intended to meet the desires of older adults, could have implications for their families.

5.
J Leukoc Biol ; 2024 Aug 30.
Article de Anglais | MEDLINE | ID: mdl-39212489

RÉSUMÉ

Neutrophils play a crucial role in maintaining lung health by defending against infections and participating in inflammation processes. Here we describe a detailed protocol for evaluating pulmonary neutrophil phenotype using a murine model of sterile inflammation induced by the fungal cell wall particle zymosan. We provide step-by-step instructions for the isolation of single cells from both lung tissues and airspaces, followed by comprehensive staining techniques for both cell surface markers and intracellular components. This protocol facilitates the sorting and detailed characterization of lung neutrophils via flow cytometry, making it suitable for downstream applications such as mRNA extraction, single-cell sequencing, and analysis of neutrophil heterogeneity. We also identify and discuss essential considerations for conducting successful neutrophil flow cytometry experiments. This work is aimed at researchers exploring the intricate functions of neutrophils in the lung under physiological and pathological conditions with the aid of flow cytometry.

6.
Biol Sex Differ ; 15(1): 54, 2024 Jul 13.
Article de Anglais | MEDLINE | ID: mdl-39003495

RÉSUMÉ

BACKGROUND: The transition from childhood to adulthood, or adolescence, a developmental stage, is characterized by psychosocial and biological changes. The nucleus accumbens (NAc), a striatal brain region composed of the core (NAcC) and shell (NAcSh), has been linked to risk-taking behavior and implicated in reward seeking and evaluation. Most neurons in the NAc are medium spiny neurons (MSNs) that express dopamine D1 receptors (D1R +) and/or dopamine D2 receptors (D2R +). Changes in dopaminergic and glutamatergic systems occur during adolescence and converge in the NAc. While there are previous investigations into sex differences in membrane excitability and synaptic glutamate transmission in both subdivisions of the NAc, to our knowledge, none have specified NAcSh D1R + MSNs from mice during pre- and mid-adolescence. METHODS: Sagittal brain slices containing the NAc were prepared from B6.Cg-Tg(Drd1a-tdTomato)6Calak/J mice of both sexes from postnatal days 21-25 and 35-47, representing pre- and mid-adolescence, respectively. Whole-cell electrophysiology recordings were collected from NAcSh D1R + MSNs in the form of membrane-voltage responses to current injections, to assess membrane properties and action potential waveform characteristics, and spontaneous excitatory postsynaptic currents (sEPSCs) to assess glutamatergic synaptic activity. RESULTS: Relative to pre-adolescent males, pre-adolescent female NAcSh D1R + MSNs exhibited a less hyperpolarized resting membrane potential, increased input resistance, and smaller action potential afterhyperpolarization amplitudes. During mid-adolescence, decreased input resistance and a shorter action potential duration in females were the only sex differences observed. CONCLUSIONS: Taken together, our results indicate that NAcSh D1R + MSNs in mice exhibit sex differences in membrane properties and AP waveform during pre-adolescence that are overall indicative of increased cellular excitability in females and are suggestive of possible sex differences in glycine receptors, inwardly-rectifying potassium channels, and large conductance voltage-gated potassium channels. These differences do not appear to persist into mid-adolescence, when sex was observed to affect input resistance oppositely to that of pre-adolescence and AP waveform in a manner suggestive of differences in voltage-gated potassium channels.


Adolescence marks a period of substantial changes in both the mind and body, where alterations in the brain's structure can influence behavior. One change in behavior exhibited by many adolescents is an increased tendency to take risks, particularly in males. While taking risks can result in positive outcomes, like learning new skills, it can also lead to reckless behaviors that may result in negative outcomes. The nucleus accumbens, a brain region tied to risk-taking and reward perception, is not well-studied during the transition from childhood to adulthood, particularly in terms of sex differences. To fill this gap in understanding, this study examined a specific type of brain cell in the nucleus accumbens of pre- and mid-adolescent male and female mice. We measured the electrical properties of these cells and assessed how they responded to manipulation of their electrical state. We also measured how much and how often excitatory electrical information is sent to these cells from other brain regions. Our results suggest that in pre-adolescent females, these brain cells are more excited by manipulations of their electrical state and that these brain cells in mid-adolescent males may take longer to communicate information to other brain regions than in similarly aged females. Understanding these intricacies of brain cell communication sheds light on potential sex-specific vulnerabilities during the transition from childhood to adulthood.


Sujet(s)
Neurones , Noyau accumbens , Récepteur dopamine D1 , Caractères sexuels , Animaux , Récepteur dopamine D1/métabolisme , Noyau accumbens/métabolisme , Noyau accumbens/physiologie , Noyau accumbens/cytologie , Femelle , Mâle , Neurones/métabolisme , Neurones/physiologie , Souris , Potentiels de membrane , Souris de lignée C57BL , Potentiels post-synaptiques excitateurs , Souris transgéniques
7.
Anal Verbal Behav ; 40(1): 1-12, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38962519

RÉSUMÉ

Procedural fidelity refers to the degree to which procedures for an assessment or intervention (i.e., independent variables) are implemented consistent with the prescribed protocols. Procedural fidelity is an important factor in demonstrating the internal validity of an experiment and clinical treatments. Previous reviews evaluating the inclusion of procedural fidelity in published empirical articles demonstrated underreporting of procedural fidelity procedures and measures within specific journals. We conducted a systematic review of The Analysis of Verbal Behavior (TAVB) to evaluate the trends in procedural fidelity reporting from 2007 to 2021. Of the 253 articles published in TAVB during the reporting period, 144 of the articles (168 studies) met inclusionary criteria for further analysis. Our results showed that 54% of studies reported procedural fidelity data, which is slightly higher than previous reviews. In comparison, interobserver-agreement data were reported for a high percentage of studies reviewed (i.e., 93%). Further discussion of results and applied research implications are included.

8.
Nurs Philos ; 25(3): e12489, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38993083

RÉSUMÉ

In this article, we investigate how the concept of Care Biography and related concepts are understood and operationalised and describe how it can be applied to advancing our understanding and practice of holistic and person-centred care. Walker and Avant's eight-step concept analysis method was conducted involving multiple database searches, with potential or actual applications of Care Biography identified based on multiple discussions among all authors. Our findings demonstrate Care Biography to be a novel overarching concept derived from the conjunction of multiple other concepts and applicable across multiple care settings. Concepts related to Care Biography exist but were more narrowly defined and mainly applied in intensive care, aged care, and palliative care settings. They are associated with the themes of Meaningfulness and Existential Coping, Empathy and Understanding, Promoting Positive Relationships, Social and Cultural Contexts, and Self-Care, which we used to inform and refine our concept analysis of Care Biography. In Conclusion, the concept of Care Biography, can provide a deeper understanding of a person and their care needs, facilitate integrated and personalised care, empower people to be in control of their care throughout their life, and help promote ethical standards of care.


Sujet(s)
Formation de concepts , Humains , Soins centrés sur le patient/normes , Empathie
10.
Health Promot Pract ; : 15248399241235925, 2024 Mar 18.
Article de Anglais | MEDLINE | ID: mdl-38500000

RÉSUMÉ

The American Public Health Association's Public Health Education and Health Promotion (APHA PHEHP) Section celebrates its 100th anniversary by reflecting on its humble beginnings and early contributions to the field of health education. This article highlights the often-unsung history of our field and its fledgling beginnings, which is important to scholars and students alike. First codified as the Health Education and Publicity Section in the early 1920s, we trace the history and challenges of using new modes of publicity such as motion pictures and innovative exhibits to help curb the spread of infectious diseases (e.g., tuberculosis, venereal disease). Evart G. Routzahn, credited as the Section's father, worked tirelessly to increase the Section's visibility (renamed the Health Education Section in 1927 and the Public Health Education and Health Promotion Section in 1990) and in advancing the professionalization of health education during a time when there were no formal professional preparation programs in health education. Over the years, the Section has played significant roles in strengthening the practice of health education and communication; advancing APHA's overall leadership, infrastructure, and governance; and contributing to the unified voice and advocacy for the health education profession and health equity. We conclude by describing contemporary initiatives that reflect the continued spirit and vibrancy of the Section in setting the stage for the next 100 years.

11.
An Acad Bras Cienc ; 96(1): e20231201, 2024.
Article de Anglais | MEDLINE | ID: mdl-38451600

RÉSUMÉ

Biotechnology offers solutions and opportunities to meet various societal demands, thereby contributing to significant scientific advancements. This study aimed to characterize the technological development of biotechnology in the healthcare sector in the state of Rio Grande do Sul, Brazil, from 2016 to 2022 by analyzing patents filed by and granted to public and private Higher Education institutions. For data collection, a quantitative exploratory approach was employed using statistical methods and a patent analysis of institutions in the patent database of the Brazilian National Institute of Industrial Property (INPI), focusing on patents related to the healthcare field. Data were collected in October, November, and December. A total of 580 patent records were collected from the INPI, belonging to Sections A and C of the International Patent Classification (IPC) related to educational institutions. Furthermore, this study highlighted that higher education institutions have a higher number of patents in the healthcare field. These results provide an understanding of the strategic areas for technological development in biotechnology in Rio Grande do Sul, Brazil.


Sujet(s)
Académies et instituts , Biotechnologie , Brésil , Universités , Bases de données factuelles
12.
J Interpers Violence ; 39(13-14): 3282-3307, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38379164

RÉSUMÉ

This research explored the content of hate crime prototypes in a North American context, with particular attention to how such prototypes might influence blame attributions. In Study 1a, participants were recruited from a blended sample of universities (n = 110) and community members (n = 102) and asked to report their thoughts about typical hate crime offenses, victims, and offenders. These open-ended responses were coded, and common themes were identified. In Study 1b, a new group of participants (n = 290) were presented with these themes and asked to rate each for their characteristics of hate crimes. Studies 1a and 1b confirmed the presence of a clear prototype of hate crimes, such that (a) perpetrators were believed to be lower status White men with clear expressions of bias, (b) hate crime offenses were believed to be acts of interpersonal violence accompanied by slurs or verbal abuse, and (c) hate crime victims were thought to be members of a marginalized group who remain passive during the offense. Study 2 explored the consequences of victim prototypes on assessments of victim blame. Participants (n = 296) were recruited from York University and presented with a case vignette that varied the prototypicality of a victim of hate, depicting him as either Black or White and either passive, verbally responsive, or physically confrontational in the context of an assault. Participants showed greatest sympathy for the Black victim who passively ignored verbal harassment but increasingly assigned blame when the Black victim spoke or reacted physically. When the victim was White, participants showed little variation in their assessment of blame as a function of the victim's behavior. These results suggest that Black victims are subjected to greater behavioral scrutiny than White victims and that sympathy for victims of hate may be contingent on their passivity in the face of harassment.


Sujet(s)
Victimes de crimes , Haine , Humains , Mâle , Victimes de crimes/psychologie , Adulte , Femelle , Jeune adulte , Adulte d'âge moyen , Perception sociale , Adolescent
13.
Phys Chem Chem Phys ; 26(9): 7844-7854, 2024 Feb 28.
Article de Anglais | MEDLINE | ID: mdl-38376373

RÉSUMÉ

A unique nanomaterial has been developed for sweat analysis, including glucose level monitoring. Simple resusable low-cost sensors from composite materials based on graphene, hexagonal boron nitride, and conductive PEDOT:PSS (poly(3,4-ethylenedioxythiophene)polystyrene sulfonate) polymer have been developed and fabricated via 2D printing on flexible substrates. The sensors were tested as biosensors using different water-based solutions. A strong increase in the current response (several orders of magnitude) was observed for aqua vapors or glucose solution vapors. This property is associated with the sorption capacity of graphene synthesized in a volume of plasma jets and thus having many active centers on the surface. The structure and properties of graphene synthesized in a plasma are different from those of graphene created by other methods. As a result, the current response for a wearable sensor is 3-5 orders of magnitude higher for the reference blood glucose concentration range of 4-14 mM. It has been found that the most promising sensor with the highest response was fabricated based on the graphene:PEDOT:PSS composite. The graphene:h-BN:PEDOT:PSS (h-BN is hexagonal boron nitride) sensors demonstrated a longer response and the highest response after the functionalization of the sensors with a glucose oxidase enzyme. The reusable wearable graphene:PEDOT:PSS glucose sensors on a paper substrate demonstrated a current response of 10-10 to 10-5 A for an operating voltage of 0.5 V and glucose range of 4-10 mM.

14.
Am J Phys Med Rehabil ; 103(3S Suppl 1): S10-S15, 2024 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-38364024

RÉSUMÉ

ABSTRACT: An evolved model of comprehensive cancer care is needed that begins at cancer diagnosis to proactively manage cancer treatment toxicities and optimize patient health, function, and well-being. Building new care models requires connecting oncology, primary care, and specialized clinicians from many disciplines including cancer rehabilitation. Having a vision for an evolved standard of comprehensive cancer care is a requirement, but it is not enough to bring an innovative clinical program to life and sustain it over the long term. To inform the development of new clinical programs, two example programs are presented that successfully integrate cancer rehabilitation services along with details of a three-step process these programs used to facilitate their success and build robust business models that ensure their sustainability. Following the roadmap for growth presented here, gaining input from stakeholders and ensuring their buy-in, leveraging existing programmatic priorities, as well as developing a strategic growth plan can help clinical innovators ensure that new programs anticipate and continually meet the needs of oncology, primary care, subspecialty care, and programs, while addressing the business needs of administrators and improving the experience for patients.


Sujet(s)
Tumeurs , Survie (démographie) , Humains , Tumeurs/rééducation et réadaptation
15.
Acad Pathol ; 11(1): 100102, 2024.
Article de Anglais | MEDLINE | ID: mdl-38179157

RÉSUMÉ

Pathology education is taught using different curricula in the United States (USA) and abroad. We evaluate and compare the hours spent in different forms of pathology teaching such as lectures, team-based learning (TBL), problem-based learning (PBL), and other methods taught in general and systemic pathology amongst different medical schools within the USA and outside the USA. The total number of lecture hours taught in general and systemic pathology combined was greater in outside schools than within the USA (141 h vs 97.8 h, respectively). Three subjects in general pathology and six subjects in systemic pathology had a significantly greater lecture hours in outside medical schools. The greatest difference was the hours spent in labs were longer for both general and systems pathology in schools outside the USA. The overall utilization of PBL in general and systemic pathology teaching combined was much greater outside the USA compared to within the USA (average overall hours PBL - 97.2 outside vs 16.5 in the USA), however, the reverse was observed for using TBL (average overall hours TBL - 59.5 outside vs 84.5 in USA). Average hours used with other methods of teaching was also greater in outside medical schools compared to USA medical schools (80.8 h vs 44 h, respectively). Pathology teaching in both general and systemic pathology has more extensive lecture hours, laboratory hours, PBL, and other methods of teaching pathology in outside medical schools with different curricula than USA medical schools. TBL is utilized more extensively in USA medical schools.

16.
Demography ; 60(6): 1903-1921, 2023 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-38009227

RÉSUMÉ

In this study, we provide an assessment of data accuracy from the 2020 Census. We compare block-level population totals from a sample of 173 census blocks in California across three sources: (1) the 2020 Census, which has been infused with error to protect respondent confidentiality; (2) the California Neighborhoods Count, the first independent enumeration survey of census blocks; and (3) projections based on the 2010 Census and subsequent American Community Surveys. We find that, on average, total population counts provided by the U.S. Census Bureau at the block level for the 2020 Census are not biased in any consistent direction. However, subpopulation totals defined by age, race, and ethnicity are highly variable. Additionally, we find that inconsistencies across the three sources are amplified in large blocks defined in terms of land area or by total housing units, blocks in suburban areas, and blocks that lack broadband access.


Sujet(s)
Recensements , Ethnies , Humains , Californie , Caractéristiques de l'habitat , Enquêtes et questionnaires
17.
Cell Rep ; 42(11): 113394, 2023 11 28.
Article de Anglais | MEDLINE | ID: mdl-37950870

RÉSUMÉ

The pore-forming S. aureus α-toxin (Hla) contributes to virulence and disease pathogenesis. While high concentrations of toxin induce cell death, neutrophils exhibit relative resistance to lysis, suggesting that the action of Hla may not be solely conferred by lytic susceptibility. Using intravital microscopy, we observed that Hla disrupts neutrophil localization and clustering early in infection. Hla forms a narrow, ion-selective pore, suggesting that Hla may dysregulate calcium or other ions to impair neutrophil function. We found that sub-lytic Hla did not permit calcium influx but caused rapid membrane depolarization. Depolarization decreases the electrogenic driving force for calcium, and concordantly, Hla suppressed calcium signaling in vitro and in vivo and calcium-dependent leukotriene B4 (LTB4) production, a key mediator of neutrophil clustering. Thus, Hla disrupts the early patterning of the neutrophil response to infection, in part through direct impairment of neutrophil calcium signaling. This early mis-localization of neutrophils may contribute to establishment of infection.


Sujet(s)
Granulocytes neutrophiles , Staphylococcus aureus , Granulocytes neutrophiles/métabolisme , Staphylococcus aureus/métabolisme , Calcium/métabolisme , Signalisation calcique
18.
iScience ; 26(10): 108034, 2023 Oct 20.
Article de Anglais | MEDLINE | ID: mdl-37854699

RÉSUMÉ

Neutrophil swarming is a complex coordinated process in which neutrophils sensing pathogen or damage signals are rapidly recruited to sites of infections or injuries. This process involves cooperation between neutrophils where autocrine and paracrine positive-feedback loops, mediated by receptor/ligand pairs including lipid chemoattractants and chemokines, amplify localized recruitment of neutrophils. This review will provide an overview of key pathways involved in neutrophil swarming and then discuss the cell intrinsic and systemic mechanisms by which NADPH oxidase 2 (NOX2) regulates swarming, including modulation of calcium signaling, inflammatory mediators, and the mobilization and production of neutrophils. We will also discuss mechanisms by which altered neutrophil swarming in disease may contribute to deficient control of infections and/or exuberant inflammation. Deeper understanding of underlying mechanisms controlling neutrophil swarming and how neutrophil cooperative behavior can be perturbed in the setting of disease may help to guide development of tools for diagnosis and precision medicine.

19.
J Appl Gerontol ; 42(12): 2277-2282, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37683281

RÉSUMÉ

We use a nationally representative study of 3451 adults who provided assistance to a relative or friend age 50 or older immediately prior to the Coronavirus Disease 2019 (COVID-19) pandemic to explore changes to care provisions, use of services, and support networks. While we see turnover in assistance during a retrospectively assessed 12-month time period, respondents exited or adopted caregiving roles primarily for reasons unrelated to the pandemic. About two thirds of caregivers' social networks remained unchanged and, of those that did change, only half lost network members without gaining others. Changes in care settings and use of support services were uncommon. Caregivers to persons with dementia may have been more adversely affected than other caregivers as they were more likely to experience loss of social ties, potentially performing more care activities without the full support system they had in place prior to the pandemic.


Sujet(s)
COVID-19 , Démence , Humains , Sujet âgé , Pandémies , COVID-19/épidémiologie , Études rétrospectives , Aidants
20.
PLoS Genet ; 19(9): e1010906, 2023 09.
Article de Anglais | MEDLINE | ID: mdl-37703303

RÉSUMÉ

Fluctuating environments threaten fertility and viability. To better match the immediate, local environment, many organisms adopt alternative phenotypic states, a phenomenon called "phenotypic plasticity." Natural populations that predictably encounter fluctuating environments tend to be more plastic than conspecific populations that encounter a constant environment, suggesting that phenotypic plasticity can be adaptive. Despite pervasive evidence of such "adaptive phenotypic plasticity," gene regulatory mechanisms underlying plasticity remains poorly understood. Here we test the hypothesis that environment-dependent phenotypic plasticity is mediated by epigenetic factors. To test this hypothesis, we exploit the adaptive reproductive arrest of Drosophila melanogaster females, called diapause. Using an inbred line from a natural population with high diapause plasticity, we demonstrate that diapause is determined epigenetically: only a subset of genetically identical individuals enter diapause and this diapause plasticity is epigenetically transmitted for at least three generations. Upon screening a suite of epigenetic marks, we discovered that the active histone marks H3K4me3 and H3K36me1 are depleted in diapausing ovaries. Using ovary-specific knockdown of histone mark writers and erasers, we demonstrate that H3K4me3 and H3K36me1 depletion promotes diapause. Given that diapause is highly polygenic, that is, distinct suites of alleles mediate diapause plasticity across distinct genotypes, we also investigated the potential for genetic variation in diapause-determining epigenetic marks. Specifically, we asked if these histone marks were similarly depleted in diapause of a genotypically distinct line. We found evidence of divergence in both the gene expression program and histone mark abundance. This study reveals chromatin determinants of phenotypic plasticity and suggests that these determinants may be genotype-dependent, offering new insight into how organisms may exploit and evolve epigenetic mechanisms to persist in fluctuating environments.


Sujet(s)
Diapause , Drosophila melanogaster , Femelle , Animaux , Drosophila melanogaster/génétique , Méthylation , Histone/génétique , Maturation post-traductionnelle des protéines
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