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1.
Cell ; 187(5): 1191-1205.e15, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38366592

RESUMO

Carbohydrate intolerance, commonly linked to the consumption of lactose, fructose, or sorbitol, affects up to 30% of the population in high-income countries. Although sorbitol intolerance is attributed to malabsorption, the underlying mechanism remains unresolved. Here, we show that a history of antibiotic exposure combined with high fat intake triggered long-lasting sorbitol intolerance in mice by reducing Clostridia abundance, which impaired microbial sorbitol catabolism. The restoration of sorbitol catabolism by inoculation with probiotic Escherichia coli protected mice against sorbitol intolerance but did not restore Clostridia abundance. Inoculation with the butyrate producer Anaerostipes caccae restored a normal Clostridia abundance, which protected mice against sorbitol-induced diarrhea even when the probiotic was cleared. Butyrate restored Clostridia abundance by stimulating epithelial peroxisome proliferator-activated receptor-gamma (PPAR-γ) signaling to restore epithelial hypoxia in the colon. Collectively, these mechanistic insights identify microbial sorbitol catabolism as a potential target for approaches for the diagnosis, treatment, and prevention of sorbitol intolerance.


Assuntos
Erros Inatos do Metabolismo dos Carboidratos , Microbioma Gastrointestinal , Sorbitol , Animais , Camundongos , Antibacterianos/farmacologia , Butiratos , Clostridium , Escherichia coli , Sorbitol/metabolismo
2.
Cell ; 186(21): 4496-4513, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37832524

RESUMO

Plant-associated microbiota can extend plant immune system function, improve nutrient acquisition and availability, and alleviate abiotic stresses. Thus, naturally beneficial microbial therapeutics are enticing tools to improve plant productivity. The basic definition of plant microbiota across species and ecosystems, combined with the development of reductionist experimental models and the manipulation of plant phenotypes with microbes, has fueled interest in its translation to agriculture. However, the great majority of microbes exhibiting plant-productivity traits in the lab and greenhouse fail in the field. Therapeutic microbes must reach détente, the establishment of uneasy homeostasis, with the plant immune system, invade heterogeneous pre-established plant-associated communities, and persist in a new and potentially remodeled community. Environmental conditions can alter community structure and thus impact the engraftment of therapeutic microbes. We survey recent breakthroughs, challenges, and opportunities in translating beneficial microbes from the lab to the field.


Assuntos
Microbiota , Plantas , Agricultura , Fenótipo , Plantas/microbiologia , Microbiologia do Solo , Estresse Fisiológico , Ecossistema
3.
Nature ; 587(7832): 103-108, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32999461

RESUMO

Plants grow within a complex web of species that interact with each other and with the plant1-10. These interactions are governed by a wide repertoire of chemical signals, and the resulting chemical landscape of the rhizosphere can strongly affect root health and development7-9,11-18. Here, to understand how interactions between microorganisms influence root growth in Arabidopsis, we established a model system for interactions between plants, microorganisms and the environment. We inoculated seedlings with a 185-member bacterial synthetic community, manipulated the abiotic environment and measured bacterial colonization of the plant. This enabled us to classify the synthetic community into four modules of co-occurring strains. We deconstructed the synthetic community on the basis of these modules, and identified interactions between microorganisms that determine root phenotype. These interactions primarily involve a single bacterial genus (Variovorax), which completely reverses the severe inhibition of root growth that is induced by a wide diversity of bacterial strains as well as by the entire 185-member community. We demonstrate that Variovorax manipulates plant hormone levels to balance the effects of our ecologically realistic synthetic root community on root growth. We identify an auxin-degradation operon that is conserved in all available genomes of Variovorax and is necessary and sufficient for the reversion of root growth inhibition. Therefore, metabolic signal interference shapes bacteria-plant communication networks and is essential for maintaining the stereotypic developmental programme of the root. Optimizing the feedbacks that shape chemical interaction networks in the rhizosphere provides a promising ecological strategy for developing more resilient and productive crops.


Assuntos
Arabidopsis/microbiologia , Comamonadaceae/classificação , Comamonadaceae/fisiologia , Microbiota/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Comamonadaceae/genética , Etilenos/metabolismo , Ácidos Indolacéticos/metabolismo , Microbiota/genética , Óperon/genética , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/genética , Rizosfera , Transdução de Sinais
4.
Proc Natl Acad Sci U S A ; 120(23): e2219396120, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37252977

RESUMO

Electric vehicle sales have been growing rapidly in the United States and around the world. This study explores the drivers of demand for electric vehicles, examining whether this trend is primarily a result of technology improvements or changes in consumer preferences for the technology over time. We conduct a discrete choice experiment of new vehicle consumers in the United States, weighted to be representative of the population. Results suggest that improved technology has been the stronger force. Estimates of consumer willingness to pay for vehicle attributes show that when consumers compare a gasoline vehicle to its battery electric vehicle (BEV) counterpart, the improved operating cost, acceleration, and fast-charging capabilities of today's BEVs mostly or entirely compensate for their perceived disadvantages, particularly for longer-range BEVs. Moreover, forecasted improvements of BEV range and price suggest that consumer valuation of many BEVs is expected to equal or exceed their gasoline counterparts by 2030. A suggestive market-wide simulation extrapolation indicates that if every gasoline vehicle had a BEV option in 2030, the majority of new car and near-majority of new sport-utility vehicle choice shares could be electric in that year due to projected technology improvements alone.

5.
Proc Natl Acad Sci U S A ; 120(11): e2220921120, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36893276

RESUMO

TIR domains are NAD-degrading enzymes that function during immune signaling in prokaryotes, plants, and animals. In plants, most TIR domains are incorporated into intracellular immune receptors termed TNLs. In Arabidopsis, TIR-derived small molecules bind and activate EDS1 heterodimers, which in turn activate RNLs, a class of cation channel-forming immune receptors. RNL activation drives cytoplasmic Ca2+ influx, transcriptional reprogramming, pathogen resistance, and host cell death. We screened for mutants that suppress an RNL activation mimic allele and identified a TNL, SADR1. Despite being required for the function of an autoactivated RNL, SADR1 is not required for defense signaling triggered by other tested TNLs. SADR1 is required for defense signaling initiated by some transmembrane pattern recognition receptors and contributes to the unbridled spread of cell death in lesion simulating disease 1. Together with RNLs, SADR1 regulates defense gene expression at infection site borders, likely in a non-cell autonomous manner. RNL mutants that cannot sustain this pattern of gene expression are unable to prevent disease spread beyond localized infection sites, suggesting that this pattern corresponds to a pathogen containment mechanism. SADR1 potentiates RNL-driven immune signaling not only through the activation of EDS1 but also partially independently of EDS1. We studied EDS1-independent TIR function using nicotinamide, an NADase inhibitor. Nicotinamide decreased defense induction from transmembrane pattern recognition receptors and decreased calcium influx, pathogen growth restriction, and host cell death following intracellular immune receptor activation. We demonstrate that TIR domains can potentiate calcium influx and defense and are thus broadly required for Arabidopsis immunity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Animais , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Cálcio/metabolismo , Receptores Imunológicos/metabolismo , Niacinamida/metabolismo , Imunidade Vegetal/genética , Doenças das Plantas/genética
6.
Annu Rev Microbiol ; 74: 81-100, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32530732

RESUMO

Methodological advances over the past two decades have propelled plant microbiome research, allowing the field to comprehensively test ideas proposed over a century ago and generate many new hypotheses. Studying the distribution of microbial taxa and genes across plant habitats has revealed the importance of various ecological and evolutionary forces shaping plant microbiota. In particular, selection imposed by plant habitats strongly shapes the diversity and composition of microbiota and leads to microbial adaptation associated with navigating the plant immune system and utilizing plant-derived resources. Reductionist approaches have demonstrated that the interaction between plant immunity and the plant microbiome is, in fact, bidirectional and that plants, microbiota, and the environment shape a complex chemical dialogue that collectively orchestrates the plantmicrobiome. The next stage in plant microbiome research will require the integration of ecological and reductionist approaches to establish a general understanding of the assembly and function in both natural and managed environments.


Assuntos
Bactérias/genética , Ecologia , Microbiota , Plantas/imunologia , Plantas/microbiologia , Adaptação Fisiológica/genética , Adaptação Fisiológica/imunologia , Bactérias/classificação , Bactérias/isolamento & purificação , Evolução Molecular , Filogenia , Fenômenos Fisiológicos Vegetais
7.
PLoS Comput Biol ; 20(2): e1011373, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38324583

RESUMO

We present the first complete stochastic model of vesicular stomatitis virus (VSV) intracellular replication. Previous models developed to capture VSV's intracellular replication have either been ODE-based or have not represented the complete replicative cycle, limiting our ability to understand the impact of the stochastic nature of early cellular infections on virion production between cells and how these dynamics change in response to mutations. Our model accurately predicts changes in mean virion production in gene-shuffled VSV variants and can capture the distribution of the number of viruses produced. This model has allowed us to enhance our understanding of intercellular variability in virion production, which appears to be influenced by the duration of the early phase of infection, and variation between variants, arising from balancing the time the genome spends in the active state, the speed of incorporating new genomes into virions, and the production of viral components. Being a stochastic model, we can also assess other effects of mutations beyond just the mean number of virions produced, including the probability of aborted infections and the standard deviation of the number of virions produced. Our model provides a biologically interpretable framework for studying the stochastic nature of VSV replication, shedding light on the mechanisms underlying variation in virion production. In the future, this model could enable the design of more complex viral phenotypes when attenuating VSV, moving beyond solely considering the mean number of virions produced.


Assuntos
Estomatite Vesicular , Animais , Estomatite Vesicular/genética , Vírus da Estomatite Vesicular Indiana/genética , Vírion/genética , Replicação Viral/genética , Mutação
8.
J Immunol ; 211(6): 944-953, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37548478

RESUMO

The pathogenic role B cells play in multiple sclerosis is underscored by the success of B cell depletion therapies. Yet, it remains unclear how B cells contribute to disease, although it is increasingly accepted that mechanisms beyond Ab production are involved. Better understanding of pathogenic interactions between B cells and autoreactive CD4 T cells will be critical for novel therapeutics. To focus the investigation on B cell:CD4 T cell interactions in vivo and in vitro, we previously developed a B cell-dependent, Ab-independent experimental autoimmune encephalomyelitis (EAE) mouse model driven by a peptide encompassing the extracellular domains of myelin proteolipid protein (PLPECD). In this study, we demonstrate that B cell depletion significantly inhibited PLPECD-induced EAE disease, blunted PLPECD-elicited delayed-type hypersensitivity reactions in vivo, and reduced CD4 T cell activation, proliferation, and proinflammatory cytokine production. Further, PLPECD-reactive CD4 T cells sourced from B cell-depleted donor mice failed to transfer EAE to naive recipients. Importantly, we identified B cell-mediated Ag presentation as the critical mechanism explaining B cell dependence in PLPECD-induced EAE, where bone marrow chimeric mice harboring a B cell-restricted MHC class II deficiency failed to develop EAE. B cells were ultimately observed to restimulate significantly higher Ag-specific proliferation from PLP178-191-reactive CD4 T cells compared with dendritic cells when provided PLPECD peptide in head-to-head cultures. We therefore conclude that PLPECD-induced EAE features a required pathogenic B cell-mediated Ag presentation function, providing for investigable B cell:CD4 T cell interactions in the context of autoimmune demyelinating disease.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Camundongos , Animais , Apresentação de Antígeno , Glicoproteína Mielina-Oligodendrócito , Linfócitos T CD4-Positivos , Proteína Proteolipídica de Mielina , Anticorpos/metabolismo
9.
Opt Express ; 32(12): 21042-21060, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859469

RESUMO

The backscattering of ultraviolet and visible light by a model organic (squalane) aerosol droplet (1.0

10.
PLoS Comput Biol ; 19(12): e1011652, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38060459

RESUMO

Information is the cornerstone of research, from experimental (meta)data and computational processes to complex inventories of reagents and equipment. These 10 simple rules discuss best practices for leveraging laboratory information management systems to transform this large information load into useful scientific findings.

11.
Infection ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300353

RESUMO

OBJECTIVES: Bartonella spp., renowned for cat-scratch disease, has limited reports of dissemination. Tissue and blood cultures have limitations in detecting this fastidious pathogen. Molecular testing (polymerase chain reaction, PCR) and cell-free DNA have provided an avenue for diagnoses. This retrospective observational multicenter study describes the incidence of disseminated Bartonella spp. and treatment-related outcomes. METHODS: Inclusion criteria were diagnosis of bartonellosis via diagnosis code, serology testing of blood, polymerase chain reaction (PCR) of blood, 16/18S tests of blood or tissue, cultures of blood or tissue, or cell-free DNA of blood or tissue from January 1, 2014, through September 1, 2021. Exclusions were patients who did not receive treatment, insufficient data on treatment course, absence of dissemination, or retinitis as dissemination. RESULTS: Patients were primarily male (n = 25, 61.0%), white (n = 28, 68.3%), with mean age of 50 years (SD 14.4), and mean Charlson comorbidity index of 3.5 (SD 2.1). Diagnosis was primarily by serology (n = 34, 82.9%), with Bartonella henselae (n = 40, 97.6%) as the causative pathogen. Treatment was principally doxycycline with rifampin (n = 17, 41.5%). Treatment failure occurred in 16 (39.0%) patients, due to escalation of therapy during treatment (n = 5, 31.3%) or discontinuation of therapy due to an adverse event or tolerability (n = 5, 31.3%). CONCLUSIONS: In conclusion, this is the largest United States-based cohort of disseminated Bartonella spp. infections to date with a reported 39% treatment failure. This adds to literature supporting obtaining multiple diagnostic tests when Bartonella is suspected and describes treatment options.

12.
Neurourol Urodyn ; 43(3): 574-578, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38238985

RESUMO

INTRODUCTION: Staged sacral neuromodulation (SNM) testing has been shown to have a high rate of progression to permanent implantation for the management of voiding dysfunction. Stage 1 lead placement (SNM-I) can be performed under monitored anesthesia care (MAC) or general anesthesia (GA). MAC allows for interpretation of sensory and motor responses to optimize lead placement while GA only permits for motor assessment. However, patient discomfort and movement can make lead placement challenging during MAC. Herein we evaluate whether the anesthesia type impacts the progression rate to permanent implantation (SNM-II). MATERIALS AND METHODS: A retrospective chart review was performed for patients who underwent SNM-I in the operating room for wet overactive bladder between 2005 and 2023. Patients were divided into two groups based on the type of anesthesia used, MAC or GA. Clinical variables and progression to SNM-II were compared between cohorts. Progression to SNM-II was based on ≥50% symptomatic improvement during a 1-2 week trial period following SNM-I. RESULTS: Of 121 patients included in the study, 95 (79%) underwent MAC and 26 (21%) GA for SNM-I. No difference in the progression rate to SNM-II was noted between groups (MAC, 68/95 patients, 72%; GA, 19/26, 73%; p = 0.39). We also found no difference when comparing the GA group to the 26 most recent MAC patients (MAC, 20/26 patients, 77%; GA, 19/26, 73%; p = 0.48). CONCLUSION: Types of anesthesia for SNM-I did not affect rate of progression to SNM-II. The result lends support to the reliance on motor responses alone for lead placement during SNM-I.


Assuntos
Anestesia , Terapia por Estimulação Elétrica , Bexiga Urinária Hiperativa , Humanos , Estudos Retrospectivos , Bexiga Urinária Hiperativa/diagnóstico , Bexiga Urinária Hiperativa/terapia , Sacro , Resultado do Tratamento
13.
Cogn Emot ; : 1-12, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512043

RESUMO

A correlational pilot study (N = 143) and an integrative data analysis of two experiments (total N = 377) provide evidence linking anger to the psychology of social hierarchy. The experiments demonstrate that the experience of anger increases the psychological accessibility of implicit cognitions related to social hierarchy: compared to participants in a control condition, participants in an anger-priming condition completed word stems with significantly more hierarchy-related words. We found little support for sex differences in the effect of anger on implicit hierarchy-related cognition; effects were equivalent across male and female participants. Findings fit with functionalist evolutionary views of anger suggesting that anger may motivate the use of dominance to strive for high social rank in group hierarchies. Implications for downstream behaviour, including aggression and negotiation, are discussed.

14.
Mol Plant Microbe Interact ; 36(3): 165-175, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36463399

RESUMO

The root microbiome is composed of distinct epiphytic (rhizosphere) and endophytic (endosphere) habitats. Differences in abiotic and biotic factors drive differences in microbial community diversity and composition between these habitats, though how they shape the interactions among community members is unknown. Here, we coupled a large-scale characterization of the rhizosphere and endosphere bacterial communities of 30 plant species across two watering treatments with co-occurrence network analysis to understand how root habitats and soil moisture shape root bacterial network properties. We used a novel bootstrapping procedure and null network modeling to overcome some of the limitations associated with microbial co-occurrence network construction and analysis. Endosphere networks had elevated node betweenness centrality versus the rhizosphere, indicating greater overall connectivity among core bacterial members of the root endosphere. Taxonomic assortativity was higher in the endosphere, whereby positive co-occurrence was more likely between bacteria within the same phylum while negative co-occurrence was more likely between bacterial taxa from different phyla. This taxonomic assortativity could be driven by positive and negative interactions among members of the same or different phylum, respectively, or by similar niche preferences associated with phylum rank among root inhabiting bacteria across plant host species. In contrast to the large differences between root habitats, drought had limited effects on network properties but did result in a higher proportion of shared co-occurrences between rhizosphere and endosphere networks. Our study points to fundamentally different ecological processes shaping bacterial co-occurrence across root habitats. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Microbiota , Microbiologia do Solo , Raízes de Plantas/microbiologia , Bactérias/genética , Rizosfera
15.
Lupus ; 32(2): 299-300, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36473694

RESUMO

Intravenous immune globulin (IVIg) therapy has been shown to be useful in a multitude of disorders. IVIg is produced from pooled human plasma; therefore, autoantibodies found in the general population are also present in IVIg and transferred to those being transfused. This can prove a particular hazard for screening and diagnostic tests based on autoantibodies. We present a patient who was found to have a positive antinuclear antibody (ANA) titer after multiple IVIg transfusions, resulting in diagnostic confusion and unnecessary workup. A 45-year-old gentleman was diagnosed with atypical CIDP, initiated on a course of IVIg, and sent for inpatient rehabilitation. However, recovery was complicated by multiple readmissions for recurrent weakness, and as part of the workup for other etiologies, an ANA was found to be positive. Sub-serologies and paraneoplastic autoantibody panel were negative. In the absence of clinical symptoms, we recommended continued monitoring and repeat ANA testing 6 months after the last dose of IVIg; as any drug needs 5 half-lives to be eliminated from the body. Clinicians should consider any recent IVIg treatments when evaluating the pre-test probability of detecting an underlying connective tissue disease with ANA screening. Indiscriminate ANA levels in patients recently given IVIg lead to unnecessary and expensive further testing and consultation.


Assuntos
Anticorpos Antinucleares , Lúpus Eritematoso Sistêmico , Masculino , Humanos , Pessoa de Meia-Idade , Imunoglobulinas Intravenosas/efeitos adversos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Autoanticorpos , Doença Iatrogênica
16.
Pure Appl Chem ; 95(8): 913-920, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38013690

RESUMO

Palladium nanostructures are interesting heterogeneous catalysts because of their high catalytic activity in a vast range of highly relevant reactions such as cross couplings, dehalogenations, and nitro-to-amine reductions. In the latter case, the catalyst Pd@GW (palladium on glass wool) shows exceptional performance and durability in reducing nitrobenzene to aniline under ambient conditions in aqueous solutions. To enhance our understanding, we use a combination of optical and electron microscopy, in-flow single molecule fluorescence, and bench chemistry combined with a fluorogenic system to develop an intimate understanding of Pd@GW in nitro-to-amine reductions. We fully characterize our catalyst in situ using advanced microscopy techniques, providing deep insights into its catalytic performance. We also explore Pd cluster migration on the surface of the support under flow conditions, providing insights into the mechanism of catalysis. We show that even under flow, Pd migration from anchoring sites seems to be minimal over 4 h, with the catalyst stability assisted by APTES anchoring.

17.
Ann Pharmacother ; 57(8): 940-947, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36453697

RESUMO

BACKGROUND: Vancomycin area-under-the-curve (AUC) monitoring is associated with reduced nephrotoxicity but may increase cost and workload for personnel compared to trough monitoring. OBJECTIVE: The purpose of this study was to compare the accuracy of vancomycin AUC calculated by open-access, online, trough-only calculators to AUCs calculated by the trapezoidal method (TM) using peak and trough concentrations. METHODS: This retrospective, multi-center study included adults ≥18 years old with stable renal function who received vancomycin with steady-state peak and trough concentrations. Areas under the curve calculated by TM were compared to AUCs calculated by 3 online calculators using trough-only options for calculation: ClinCalc, VancoVanco, and VancoPK. The primary outcome was actual difference in AUC between TM and the online calculators. Secondary outcomes were percent difference in AUC and clinical alignment in dose adjustments between methods. RESULTS: Seventy patients were included for analysis. There was a statistically significant difference in AUC between TM and ClinCalc (median actual difference: -52, P < 0.001) and VancoVanco (median actual difference: 95, P < 0.001), whereas there was no significant difference between TM and VancoPK (median actual difference: -0.8, P = 0.827). Discordant dose adjustments were indicated when comparing ClinCalc, VancoVanco, and VancoPK to TM in 28%, 36%, and 12% of cases, respectively. CONCLUSION: The AUC calculator most closely aligned with TM was VancoPK, whereas other included calculators were statistically different. Owing to the cost and complexity of obtaining multiple levels, our findings support using a single steady-state trough using VancoPK as an alternative to TM for calculation of vancomycin AUC.


Assuntos
Antibacterianos , Vancomicina , Adulto , Humanos , Adolescente , Antibacterianos/uso terapêutico , Estudos Retrospectivos , Área Sob a Curva , Testes de Sensibilidade Microbiana
18.
J Behav Med ; 46(3): 417-428, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36400880

RESUMO

This research differentiated childhood unpredictability (i.e., perceptions of uncertainty or instability due to turbulent environmental changes) from other related constructs to identify its role in adult health. Study 1 (N = 441) showed that, beyond other childhood adversity variables (poverty and adverse childhood experiences or ACEs) and demographic characteristics, perceptions of unpredictability were associated with greater functional disability and worse health-related quality of life (assessed via the CDC's HRQOL Healthy Days measure and the RAND SF-36). Study 2 (N = 564) replicated those findings in a more racially diverse sample and showed that associations with childhood unpredictability held while also controlling for the Big 5 personality traits. Findings suggest that effects of unpredictability were especially pronounced among Hispanic (in Study 1), and Black/African American and low-income participants (in Study 2). Experiencing childhood environments that are perceived to be uncertain, unstable, or uncontrollable may put children on a path toward poor health outcomes in adulthood. Findings advance theories of child adversity and health and identify childhood unpredictability as a potentially valuable target for intervention.


Assuntos
Experiências Adversas da Infância , Qualidade de Vida , Criança , Adulto , Humanos , Nível de Saúde , Pobreza , Incerteza
19.
Proc Natl Acad Sci U S A ; 117(28): 16448-16455, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601224

RESUMO

Mitochondrial and plastid genomes in land plants exhibit some of the slowest rates of sequence evolution observed in any eukaryotic genome, suggesting an exceptional ability to prevent or correct mutations. However, the mechanisms responsible for this extreme fidelity remain unclear. We tested seven candidate genes involved in cytoplasmic DNA replication, recombination, and repair (POLIA, POLIB, MSH1, RECA3, UNG, FPG, and OGG1) for effects on mutation rates in the model angiosperm Arabidopsis thaliana by applying a highly accurate DNA sequencing technique (duplex sequencing) that can detect newly arisen mitochondrial and plastid mutations even at low heteroplasmic frequencies. We find that disrupting MSH1 (but not the other candidate genes) leads to massive increases in the frequency of point mutations and small indels and changes to the mutation spectrum in mitochondrial and plastid DNA. We also used droplet digital PCR to show transmission of de novo heteroplasmies across generations in msh1 mutants, confirming a contribution to heritable mutation rates. This dual-targeted gene is part of an enigmatic lineage within the mutS mismatch repair family that we find is also present outside of green plants in multiple eukaryotic groups (stramenopiles, alveolates, haptophytes, and cryptomonads), as well as certain bacteria and viruses. MSH1 has previously been shown to limit ectopic recombination in plant cytoplasmic genomes. Our results point to a broader role in recognition and correction of errors in plant mitochondrial and plastid DNA sequence, leading to greatly suppressed mutation rates perhaps via initiation of double-stranded breaks and repair pathways based on faithful homologous recombination.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Mitocôndrias/genética , Proteína MutS de Ligação de DNA com Erro de Pareamento/metabolismo , Plastídeos/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Genoma Mitocondrial , Genoma de Planta , Genomas de Plastídeos , Mitocôndrias/metabolismo , Proteína MutS de Ligação de DNA com Erro de Pareamento/genética , Mutação , Taxa de Mutação , Plastídeos/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-37348808

RESUMO

Although pervasive, the effects of climate change vary regionally, possibly resulting in differential behavioral, physiological, and/or phenotypic responses among populations within broadly distributed species. Juvenile Port Jackson sharks (Heterodontus portusjacksoni) from eastern and southern Australia were reared at their current (17.6 °C Adelaide, South Australia [SA]; 20.6 °C Jervis Bay, New South Wales [NSW]) or projected end-of-century (EOC) temperatures (20.6 °C Adelaide, SA; 23.6 °C Jervis Bay, NSW) and assessed for morphological features of skeletal muscle tissue. Nearly all skeletal muscle properties including cellularity, fiber size, myonuclear domain, and satellite cell density did not differ between locations and thermal regimes. However, capillary density was significantly influenced by thermal treatment, where Adelaide sharks raised at current temperatures had a lower capillarity than Jervis Bay sharks raised at ambient or projected EOC temperatures. This may indicate higher metabolic costs at elevated temperatures. However, our results suggest that regardless of the population, juvenile Port Jackson sharks may have limited acclimatory potential to alter muscle metabolic features under a temperature increase, which may make this species vulnerable to climate change.


Assuntos
Tubarões , Animais , Tubarões/fisiologia , Temperatura , Músculo Esquelético/metabolismo
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