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1.
Proc Natl Acad Sci U S A ; 114(34): E7205-E7214, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28784761

RESUMO

Optimal defense (OD) theory predicts that within a plant, tissues are defended in proportion to their fitness value and risk of predation. The fitness value of leaves varies greatly and leaves are protected by jasmonate (JA)-inducible defenses. Flowers are vehicles of Darwinian fitness in flowering plants and are attacked by herbivores and pathogens, but how they are defended is rarely investigated. We used Nicotiana attenuata, an ecological model plant with well-characterized herbivore interactions to characterize defense responses in flowers. Early floral stages constitutively accumulate greater amounts of two well-characterized defensive compounds, the volatile (E)-α-bergamotene and trypsin proteinase inhibitors (TPIs), which are also found in herbivore-induced leaves. Plants rendered deficient in JA biosynthesis or perception by RNA interference had significantly attenuated floral accumulations of defensive compounds known to be regulated by JA in leaves. By RNA-seq, we found a JAZ gene, NaJAZi, specifically expressed in early-stage floral tissues. Gene silencing revealed that NaJAZi functions as a flower-specific jasmonate repressor that regulates JAs, (E)-α-bergamotene, TPIs, and a defensin. Flowers silenced in NaJAZi are more resistant to tobacco budworm attack, a florivore. When the defensin was ectopically expressed in leaves, performance of Manduca sexta larvae, a folivore, decreased. NaJAZi physically interacts with a newly identified NINJA-like protein, but not the canonical NINJA. This NINJA-like recruits the corepressor TOPLESS that contributes to the suppressive function of NaJAZi on floral defenses. This study uncovers the defensive function of JA signaling in flowers, which includes components that tailor JA signaling to provide flower-specific defense.


Assuntos
Ciclopentanos/imunologia , Flores/imunologia , Nicotiana/imunologia , Oxilipinas/imunologia , Proteínas de Plantas/imunologia , Animais , Comportamento Alimentar , Flores/parasitologia , Regulação da Expressão Gênica de Plantas , Manduca/fisiologia , Proteínas de Plantas/genética , Nicotiana/genética , Nicotiana/parasitologia
2.
BMC Evol Biol ; 15: 282, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26672978

RESUMO

BACKGROUND: Immune response induction benefits insects in combatting infection by pathogens. However, organisms have a limited amount of resources available and face the dilemma of partitioning resources between immunity and other life-history traits. Since males and females differ in their life histories, sex-specific resource investment strategies to achieve an optimal immune response following an infection can be expected. We investigated immune response induction of females and males of Heliothis virescens in response to the entomopathogenic bacterium Serratia entomophila, and its effects on mating success and the female sexual signal. RESULTS: We found that females had higher expression levels of immune-related genes after bacterial challenge than males. However, males maintained a higher baseline expression of immune-related genes than females. The increased investment in immunity of female moths was negatively correlated with mating success and the female sexual signal. Male mating success was unaffected by bacterial challenge. CONCLUSIONS: Our results show that the sexes differed in their investment strategies: females invested in immune defense after a bacterial challenge, indicating facultative immune deployment, whereas males had higher baseline immunity than females, indicating immune maintenance. Interestingly, these differences in investment were reflected in the mate choice assays. As female moths are the sexual signallers, females need to invest resources in their attractiveness. However, female moths appeared to invest in immunity at the cost of reproductive effort.


Assuntos
Mariposas/imunologia , Mariposas/fisiologia , Serratia/fisiologia , Animais , Feminino , Estágios do Ciclo de Vida , Masculino , Mariposas/crescimento & desenvolvimento , Mariposas/microbiologia , Reprodução , Caracteres Sexuais , Transcriptoma
3.
Proc Biol Sci ; 281(1788): 20140897, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-24943370

RESUMO

Ecological immunology examines the adaptive responses of animals to pathogens in relation to other environmental factors and explores the consequences of trade-offs between investment in immune function and other life-history traits. Among species of herbivorous insects, diet breadth may vary greatly, with generalists consuming a wide variety of plant families and specialists restricted to a few species. Generalists may thus be exposed to a wider range of pathogens exerting stronger selection on the innate immune system. To examine whether this produces an increase in the robustness of the immune response, we compared larvae of the generalist herbivore Heliothis virescens and the specialist Heliothis subflexa challenged by entomopathogenic and non-pathogenic bacteria. Heliothis virescens larvae showed lower mortality, a lower number of recoverable bacteria, lower proliferation of haemocytes and higher phagocytic activity. These results indicate a higher tolerance to entomopathogenic bacteria by the generalist, which is associated with a more efficient cell-mediated immune response by mechanisms that differ between these closely related species. Our findings provide novel insights into the consequences of diet breadth and related environmental factors, which may be significant in further studies to understand the ecological forces and investment trade-offs that shape the evolution of innate immunity.


Assuntos
Bacillus subtilis/fisiologia , Bacillus thuringiensis/fisiologia , Mariposas/fisiologia , Serratia/fisiologia , Animais , Dieta , Larva/imunologia , Larva/microbiologia , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Mariposas/imunologia , Mariposas/microbiologia , Especificidade da Espécie
4.
Health Serv Res ; 58(1): 30-39, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36146904

RESUMO

OBJECTIVE: To propose and evaluate a novel approach for measuring hospital-level disparities according to the effect of a continuous, polysocial risk factor on those outcomes. STUDY SETTING: Our cohort consisted of Medicare Fee-for-Service (FFS) patients 65 years and older admitted to acute care hospitals for one of six common conditions or procedures. Medicare administrative claims data for six hospital readmission measures including hospitalizations from July 2015 to June 2018 were used. STUDY DESIGN: We adapted existing methodologies that were developed to report hospital-level disparities using dichotomous social risk factors (SRFs). The existing methods report disparities within and across hospitals; we developed and tested modified approaches for both methods using the Agency for Healthcare Research and Quality Socioeconomic Status Index. We applied the adapted methodologies to six 30-day hospital readmission measures included in the Centers for Medicare & Medicaid Services Hospital Readmissions Reduction Program measures. We compared the within- and across-hospital results for each to those obtained from using the original methods and dichotomizing the AHRQ SES Index into "low" and "high" scores. DATA COLLECTION: We used Medicare FFS administrative claims data linked to U.S. Census data. PRINCIPAL FINDINGS: For all six readmission measures we find that, when compared with the existing methods, the methods for continuous SRFs provide disparity results for more facilities though across a narrower range of values. Measures of disparity based on this approach are moderately to highly correlated with those based on a dichotomous version of the same risk factor, while reflecting a fuller spectrum of risk. This approach represents an opportunity for detection of provider-level results that more closely align with underlying social risk. CONCLUSION: We have demonstrated the feasibility and utility of estimating hospital disparities of care using a continuous, polysocial risk factor. This approach expands the potential for reporting hospital-level disparities while better accounting for the multifactorial nature of social risk on hospital outcomes.


Assuntos
Hospitalização , Medicare , Humanos , Idoso , Estados Unidos , Readmissão do Paciente , Hospitais , Fatores de Risco
5.
JAMA Health Forum ; 4(3): e230081, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36897581

RESUMO

Importance: Adjusting quality measures used in pay-for-performance programs for social risk factors remains controversial. Objective: To illustrate a structured, transparent approach to decision-making about adjustment for social risk factors for a measure of clinician quality that assesses acute admissions for patients with multiple chronic conditions (MCCs). Design, Setting, and Participants: This retrospective cohort study used 2017 and 2018 Medicare administrative claims and enrollment data, 2013 to 2017 American Community Survey data, and 2018 and 2019 Area Health Resource Files. Patients were Medicare fee-for-service beneficiaries 65 years or older with at least 2 of 9 chronic conditions (acute myocardial infarction, Alzheimer disease/dementia, atrial fibrillation, chronic kidney disease, chronic obstructive pulmonary disease or asthma, depression, diabetes, heart failure, and stroke/transient ischemic attack). Patients were attributed to clinicians in the Merit-Based Incentive Payment System (MIPS; primary health care professionals or specialists) using a visit-based attribution algorithm. Analyses were conducted between September 30, 2017, and August 30, 2020. Exposures: Social risk factors included low Agency for Healthcare Research and Quality Socioeconomic Status Index, low physician-specialist density, and Medicare-Medicaid dual eligibility. Main Outcomes and Measures: Number of acute unplanned hospital admissions per 100 person-years at risk for admission. Measure scores were calculated for MIPS clinicians with at least 18 patients with MCCs assigned to them. Results: There were 4 659 922 patients with MCCs (mean [SD] age, 79.0 [8.0] years; 42.5% male) assigned to 58 435 MIPS clinicians. The median (IQR) risk-standardized measure score was 38.9 (34.9-43.6) per 100 person-years. Social risk factors of low Agency for Healthcare Research and Quality Socioeconomic Status Index, low physician-specialist density, and Medicare-Medicaid dual eligibility were significantly associated with the risk of hospitalization in the univariate models (relative risk [RR], 1.14 [95% CI, 1.13-1.14], RR, 1.05 [95% CI, 1.04-1.06], and RR, 1.44 [95% CI, 1.43-1.45], respectively), but the association was attenuated in adjusted models (RR, 1.11 [95% CI 1.11-1.12] for dual eligibility). Across MIPS clinicians caring for variable proportions of dual-eligible patients with MCCs (quartile 1, 0%-3.1%; quartile 2, >3.1%-9.5%; quartile 3, >9.5%-24.5%, and quartile 4, >24.5%-100%), median measure scores per quartile were 37.4, 38.6, 40.0, and 39.8 per 100 person-years, respectively. Balancing conceptual considerations, empirical findings, programmatic structure, and stakeholder input, the Centers for Medicare & Medicaid Services decided to adjust the final model for the 2 area-level social risk factors but not dual Medicare-Medicaid eligibility. Conclusions and Relevance: This cohort study demonstrated that adjustment for social risk factors in outcome measures requires weighing high-stake, competing concerns. A structured approach that includes evaluation of conceptual and contextual factors, as well as empirical findings, with active engagement of stakeholders can be used to make decisions about social risk factor adjustment.


Assuntos
Medicare , Múltiplas Afecções Crônicas , Humanos , Masculino , Idoso , Estados Unidos , Feminino , Medicaid , Estudos de Coortes , Reembolso de Incentivo , Estudos Retrospectivos , Hospitalização , Fatores de Risco
6.
J Am Heart Assoc ; 12(18): e027225, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37702090

RESUMO

Background Though associations between obstructive sleep apnea (OSA) and cardiovascular outcomes are well described, limited data exist regarding the impact of OSA on sex-specific outcomes after acute myocardial infarction (AMI). Methods and Results The VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) study enrolled 3572 adults aged 18 to 55 years with AMI from the United States and Spain during 2008 to 2012. We included patients for whom the Berlin Questionnaire for OSA was scored at the time of AMI admission (3141; 2105 women, 1036 men). We examined the sex-specific association between baseline OSA risk with functional outcomes including health status and depressive symptoms at 1 and 12 months after AMI. Among both groups, 49% of patients were at high risk for OSA (1040 women; 509 men), but only 4.7% (148) of patients had a diagnosed history of OSA. Though patients with a high OSA risk reported worse physical and mental health status and depression than low-risk patients in both sexes, the difference in these functional outcomes was wider in women than men. Moreover, women with a high OSA risk had worse health status, depression, and quality of life than high-risk men, both at baseline and at 1 and 12 months after AMI. Conclusions Young women with a high OSA risk have poorer health status and more depressive symptoms than men at the time of AMI, which may place them at higher risk of poorer health outcomes over the year following the AMI. Further, the majority of patients at high risk of OSA are undiagnosed at the time of presentation of AMI.


Assuntos
Infarto do Miocárdio , Apneia Obstrutiva do Sono , Adulto , Masculino , Humanos , Feminino , Qualidade de Vida , Comportamento Sexual , Infarto do Miocárdio/epidemiologia , Nível de Saúde , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia
7.
JAMA Netw Open ; 6(11): e2342151, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37938846

RESUMO

Importance: No data comparing the estimated effectiveness of coadministering COVID-19 vaccines with seasonal influenza vaccine (SIV) in the community setting exist. Objective: To examine the comparative effectiveness associated with coadministering the BNT162b2 BA.4/5 bivalent mRNA COVID-19 vaccine (BNT162b2-biv [Pfizer BioNTech]) and SIV vs giving each vaccine alone. Design, Setting, and Participants: A retrospective comparative effectiveness study evaluated US adults aged 18 years or older enrolled in commercial health insurance or Medicare Advantage plans and vaccinated with BNT162b2-biv only, SIV only, or both on the same day between August 31, 2022, and January 30, 2023. Individuals with monovalent or another brand of mRNA bivalent COVID-19 vaccine were excluded. Exposure: Same-day coadministration of BNT162b2-biv and SIV; receipt of BNT162b2-biv only (for COVID-19-related outcomes) or SIV only (for influenza-related outcomes) were the comparator groups. For adults aged 65 years or older, only enhanced SIVs were included. Main Outcomes and Measures: COVID-19-related and influenza-related hospitalization, emergency department (ED) or urgent care (UC) encounters, and outpatient visits. Results: Overall, 3 442 996 individuals (57.0% female; mean [SD] age, 65 [16.7] years) were included. A total of 627 735 individuals had BNT162b2-biv and SIV vaccine coadministered, 369 423 had BNT162b2-biv alone, and 2 445 838 had SIV alone. Among those aged 65 years or older (n = 2 210 493; mean [SD] age, 75 [6.7] years; 57.9% female), the coadministration group had a similar incidence of COVID-19-related hospitalization (adjusted hazard ratio [AHR], 1.04; 95% CI, 0.87-1.24) and slightly higher incidence of emergency department or urgent care encounters (AHR, 1.12; 95% CI, 1.02-1.23) and outpatient visits (AHR, 1.06; 95% CI, 1.01-1.11) compared with the BNT162b2-biv-only group. Among individuals aged 18 to 64 years (n = 1 232 503; mean [SD] age, 47 [13.1] years; 55.4% female), the incidence of COVID-19-related outcomes was slightly higher among those who received both vaccines vs BNT162b2-biv alone (AHR point estimate range, 1.14-1.57); however, fewer events overall in this age group resulted in wider CIs. Overall, compared with those who received SIV alone, the coadministration group had a slightly lower incidence of most influenza-related end points (AHR point estimates 0.83-0.93 for those aged ≥65 years vs 0.76-1.08 for those aged 18-64 years). Negative control outcomes suggested residual bias and calibration of COVID-19-related and influenza-related outcomes with negative controls moved all estimates closer to the null, with most CIs crossing 1.00. Conclusions and Relevance: In this study, coadministration of BNT162b2-biv and SIV was associated with generally similar effectiveness in the community setting against COVID-19-related and SIV-related outcomes compared with giving each vaccine alone and may help improve uptake of both vaccines.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , Estados Unidos/epidemiologia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Masculino , Vacina BNT162 , Vacinas contra COVID-19 , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Estudos Retrospectivos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Medicare , RNA Mensageiro
8.
JAMA Health Forum ; 2(7): e211323, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-35977204

RESUMO

Importance: Hospitals can face significant clinical and financial challenges in caring for patients with social risk factors. Currently the Hospital Readmission Reduction Program stratifies hospitals by proportion of patients eligible for both Medicare and Medicaid when calculating payment penalties to account for the patient population. However, additional social risk factors should be considered. Objective: To evaluate 7 different definitions of social risk and understand the degree to which differing definitions identify the same hospitals caring for a high proportion of patients with social risk factors. Design Setting and Participants: Across 18 publicly reported Centers for Medicare & Medicaid Services (CMS) hospital performance measures, highly disadvantaged hospitals were identified by the the proportion of patients with social risk factors using the following 7 commonly used definitions of social risk: living below the US poverty line, educational attainment of less than high school, unemployment, living in a crowded household, African American race (as a proxy for the social risk factor of exposure to racism), Medicaid coverage, and Agency for Healthcare Research and Quality index of socioeconomic status score. In this cross-sectional study, social risk factors were evaluated by measure because hospitals may serve a disadvantaged patient population for one measure but not another. Data were collected from April 1, 2014, to June 30, 2017, and analyzed from July 25, 2019, to April 25, 2021. Main Outcomes and Measures: The proportion of hospitals identified as caring for patients with social risk factors using 7 definitions of social risk, across 18 publicly reported CMS hospital performance measures. Results: Among 4465 hospitals, a mean of 31.0% (range, 28.9%-32.3%) were identified at least once when using the 7 definitions of social risk as caring for a high proportion of patients with social risk factors. Among all hospitals meeting at least 1 definition of social risk, a mean of 0.7% (range, 0%-1.0%) were identified as highly disadvantaged by all 7 definitions. Among hospitals meeting at least 1 definition of social risk, a mean of 2.7% (range, 1.3%-5.1%) were identified by 6 definitions; 6.5% (range, 5.9%-7.1%), by 5 definitions; 10.4% (range, 9.5%-12.1%), by 4 definitions; 13.2% (range, 10.1%-14.4%), by 3 definitions; 21.4% (range, 20.1%-22.4%), by 2 definitions; and 45.2% (range, 42.6%-47.1%), by only 1 definition. This pattern was consistent across all 18 performance measures. Conclusions and Relevance: In this cross-sectional study, there were inconsistencies in the identification of hospitals caring for disadvantaged populations using different definitions of social risk factors. Without consensus on how to define disadvantaged hospitals, policies to support such hospitals may be applied inconsistently.


Assuntos
Hospitais , Medicare , Idoso , Estudos Transversais , Humanos , Medicaid , Fatores de Risco , Estados Unidos/epidemiologia
9.
Arthritis Care Res (Hoboken) ; 73(10): 1470-1478, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-32583971

RESUMO

OBJECTIVE: The present study was undertaken to evaluate the efficacy of 2 educational tools for patients with rheumatoid arthritis (RA) by comparing a newly developed video tool, including storylines and testimonials, combined with a written booklet to the same written booklet alone. METHODS: We conducted a randomized controlled trial. Our primary outcome was disease knowledge. Secondary outcomes were decisional conflict, self-efficacy, effective health care management, and satisfaction. Outcomes were measured before and after reviewing the materials, and 3 and 6 months later. Linear mixed-effects models were performed to evaluate changes over time. RESULTS: In total, 221 participants received an educational video and booklet (n = 111) or a booklet alone (n = 110). The mean age was 50.8 years, mean disease duration was 4.8 years, 85% were female, and 24% had limited health literacy levels. Within groups, most outcomes improved between baseline and follow-up, but there were no statistically significant differences across groups. Patients receiving the video and booklet were more likely than those receiving the booklet alone to rate the presentation as excellent for providing information about the impact of RA, medication options, evidence about medications, benefits of medication, and self-care options. Factors significantly associated with greater improvements in knowledge and decisional conflict from baseline to 6 months included limited health literacy, lower educational level, and shorter disease duration. CONCLUSION: Regardless of the delivery method, outcomes were improved up to 6 months after educational materials were delivered. Our findings support the implementation of self-administered educational materials in clinical settings, as they can result in sustained improvements in disease knowledge and decisional conflict.


Assuntos
Artrite Reumatoide/terapia , Folhetos , Educação de Pacientes como Assunto , Autocuidado , Gravação em Vídeo , Adulto , Idoso , Artrite Reumatoide/diagnóstico , Conflito Psicológico , Tomada de Decisões , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Letramento em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Autoeficácia , Texas , Fatores de Tempo , Resultado do Tratamento
10.
Nat Commun ; 7: 12530, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27561781

RESUMO

The development of novel plant chemical defenses and counter adaptations by herbivorous insect could continually drive speciation, producing more insect specialists than generalists. One approach to test this hypothesis is to compare closely related generalist and specialist species to reveal the associated costs and benefits of these different adaptive strategies. We use the specialized moth Heliothis subflexa, which feeds exclusively on plants in the genus Physalis, and its close generalist relative H. virescens. Specialization on Physalis plants necessitates the ability to tolerate withanolides, the secondary metabolites of Physalis species that are known to have feeding deterrent and immune inhibiting properties for other insects. Here we find that only H. subflexa benefits from the antibacterial properties of withanolides, and thereby gains a higher tolerance of the pathogen Bacillus thuringiensis. We argue that the specialization in H. subflexa has been guided to a large extent by a unique role of plant chemistry on ecological immunology.


Assuntos
Bacillus thuringiensis , Mariposas/imunologia , Physalis/microbiologia , Vitanolídeos/imunologia , Animais , Herbivoria
11.
J Insect Physiol ; 57(2): 231-45, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21078327

RESUMO

Gene silencing through RNA interference (RNAi) has revolutionized the study of gene function, particularly in non-model insects. However, in Lepidoptera (moths and butterflies) RNAi has many times proven to be difficult to achieve. Most of the negative results have been anecdotal and the positive experiments have not been collected in such a way that they are possible to analyze. In this review, we have collected detailed data from more than 150 experiments including all to date published and many unpublished experiments. Despite a large variation in the data, trends that are found are that RNAi is particularly successful in the family Saturniidae and in genes involved in immunity. On the contrary, gene expression in epidermal tissues seems to be most difficult to silence. In addition, gene silencing by feeding dsRNA requires high concentrations for success. Possible causes for the variability of success in RNAi experiments in Lepidoptera are discussed. The review also points to a need to further investigate the mechanism of RNAi in lepidopteran insects and its possible connection to the innate immune response. Our general understanding of RNAi in Lepidoptera will be further aided in the future as our public database at http://insectacentral.org/RNAi will continue to gather information on RNAi experiments.


Assuntos
Regulação da Expressão Gênica , Lepidópteros/genética , Lepidópteros/imunologia , Interferência de RNA , Animais , Bases de Dados Genéticas , Epiderme/crescimento & desenvolvimento , Inativação Gênica , Imunidade Inata , Proteínas de Insetos/efeitos dos fármacos , Proteínas de Insetos/genética , Proteínas de Insetos/imunologia , Lepidópteros/efeitos dos fármacos , Lepidópteros/crescimento & desenvolvimento , RNA de Cadeia Dupla/efeitos dos fármacos , Projetos de Pesquisa
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