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1.
Nat Immunol ; 25(1): 41-53, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38036767

RESUMO

Bacille Calmette-Guérin (BCG) vaccination can confer nonspecific protection against heterologous pathogens. However, the underlying mechanisms remain mysterious. We show that mice vaccinated intravenously with BCG exhibited reduced weight loss and/or improved viral clearance when challenged with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 B.1.351) or PR8 influenza. Protection was first evident between 14 and 21 d post-vaccination and lasted ∼3 months. Notably, BCG induced a biphasic innate response and robust antigen-specific type 1 helper T cell (TH1 cell) responses in the lungs. MyD88 signaling was essential for innate and TH1 cell responses, and protection against SARS-CoV-2. Depletion of CD4+ T cells or interferon (IFN)-γ activity before infection obliterated innate activation and protection. Single-cell and spatial transcriptomics revealed CD4-dependent expression of IFN-stimulated genes in lung myeloid and epithelial cells. Notably, BCG also induced protection against weight loss after mouse-adapted SARS-CoV-2 BA.5, SARS-CoV and SHC014 coronavirus infections. Thus, BCG elicits integrated organ immunity, where CD4+ T cells feed back on tissue myeloid and epithelial cells to imprint prolonged and broad innate antiviral resistance.


Assuntos
Imunidade Adaptativa , Vacina BCG , Animais , Camundongos , Humanos , Retroalimentação , Vacinação , Redução de Peso , Antivirais , Imunidade Inata
2.
Immunity ; 56(11): 2570-2583.e6, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37909039

RESUMO

Dimeric IgA (dIgA) can move through cells via the IgA/IgM polymeric immunoglobulin receptor (PIGR), which is expressed mainly on mucosal epithelia. Here, we studied the ability of dIgA to target commonly mutated cytoplasmic oncodrivers. Mutation-specific dIgA, but not IgG, neutralized KRASG12D within ovarian carcinoma cells and expelled this oncodriver from tumor cells. dIgA binding changed endosomal trafficking of KRASG12D from accumulation in recycling endosomes to aggregation in the early/late endosomes through which dIgA transcytoses. dIgA targeting of KRASG12D abrogated tumor cell proliferation in cell culture assays. In vivo, KRASG12D-specific dIgA1 limited the growth of KRASG12D-mutated ovarian and lung carcinomas in a manner dependent on CD8+ T cells. dIgA specific for IDH1R132H reduced colon cancer growth, demonstrating effective targeting of a cytoplasmic oncodriver not associated with surface receptors. dIgA targeting of KRASG12D restricted tumor growth more effectively than small-molecule KRASG12D inhibitors, supporting the potential of this approach for the treatment of human cancers.


Assuntos
Carcinoma , Imunoglobulina A , Humanos , Imunoglobulina A/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Citoplasma/metabolismo
3.
Immunity ; 55(1): 115-128.e9, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35021053

RESUMO

The immune checkpoint receptor PD-1 on T follicular helper (Tfh) cells promotes Tfh:B cell interactions and appropriate positioning within tissues. Here, we examined the impact of regulation of PD-1 expression by the genomic organizer SATB1 on Tfh cell differentiation. Vaccination of CD4CreSatb1f/f mice enriched for antigen-specific Tfh cells, and TGF-ß-mediated repression of SATB1 enhanced Tfh differentiation of human T cells. Mechanistically, high Icos expression in Satb1-/- CD4+ T cells promoted Tfh cell differentiation by preventing T follicular regulatory cell skewing and resulted in increased isotype-switched B cell responses in vivo. Ovarian tumors in CD4CreSatb1f/f mice accumulated tumor antigen-specific, LIGHT+CXCL13+IL-21+ Tfh cells and tertiary lymphoid structures (TLS). TLS formation decreased tumor growth in a CD4+ T cell and CXCL13-dependent manner. The transfer of Tfh cells, but not naive CD4+ T cells, induced TLS at tumor beds and decreased tumor growth. Thus, TGF-ß-mediated silencing of Satb1 licenses Tfh cell differentiation, providing insight into the genesis of TLS within tumors.


Assuntos
Centro Germinativo/imunologia , Linfócitos do Interstício Tumoral/imunologia , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Estruturas Linfoides Terciárias/imunologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Diferenciação Celular , Regulação da Expressão Gênica , Inativação Gênica , Genótipo , Proteínas de Ligação à Região de Interação com a Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Fator de Crescimento Transformador beta/genética
4.
PLoS Pathog ; 20(6): e1011569, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38900807

RESUMO

Antibodies perform both neutralizing and non-neutralizing effector functions that protect against certain pathogen-induced diseases. A human antibody directed at the SARS-CoV-2 Spike N-terminal domain (NTD), DH1052, was recently shown to be non-neutralizing, yet it protected mice and cynomolgus macaques from severe disease. The mechanisms of NTD non-neutralizing antibody-mediated protection are unknown. Here we show that Fc effector functions mediate NTD non-neutralizing antibody (non-nAb) protection against SARS-CoV-2 MA10 viral challenge in mice. Though non-nAb prophylactic infusion did not suppress infectious viral titers in the lung as potently as neutralizing antibody (nAb) infusion, disease markers including gross lung discoloration were similar in nAb and non-nAb groups. Fc functional knockout substitutions abolished non-nAb protection and increased viral titers in the nAb group. Fc enhancement increased non-nAb protection relative to WT, supporting a positive association between Fc functionality and degree of protection from SARS-CoV-2 infection. For therapeutic administration of antibodies, non-nAb effector functions contributed to virus suppression and lessening of lung discoloration, but the presence of neutralization was required for optimal protection from disease. This study demonstrates that non-nAbs can utilize Fc-mediated mechanisms to lower viral load and prevent lung damage due to coronavirus infection.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Fragmentos Fc das Imunoglobulinas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , SARS-CoV-2/imunologia , Camundongos , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Anticorpos Antivirais/imunologia , Anticorpos Neutralizantes/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Humanos , Feminino , Domínios Proteicos/imunologia , Carga Viral , Pulmão/virologia , Pulmão/imunologia , Pulmão/patologia
6.
Cancer Immunol Immunother ; 72(6): 1445-1460, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36469096

RESUMO

Radiation therapy (RT) can prime and boost systemic anti-tumor effects via STING activation, resulting in enhanced tumor antigen presentation and antigen recognition by T cells. It is increasingly recognized that optimal anti-tumor immune responses benefit from coordinated cellular (T cell) and humoral (B cell) responses. However, the nature and functional relevance of the RT-induced immune response are controversial, beyond STING signaling, and agonistic interventions are lacking. Here, we show that B and CD4+ T cell accumulation at tumor beds in response to RT precedes the arrival of CD8+ T cells, and both cell types are absolutely required for abrogated tumor growth in non-irradiated tumors. Further, RT induces increased expression of 4-1BB (CD137) in both T and B cells; both in preclinical models and in a cohort of patients with small cell lung cancer treated with thoracic RT. Accordingly, the combination of RT and anti-41BB therapy leads to increased immune cell infiltration in the tumor microenvironment and significant abscopal effects. Thus, 4-1BB therapy enhances radiation-induced tumor-specific immune responses via coordinated B and T cell responses, thereby preventing malignant progression at unirradiated tumor sites. These findings provide a rationale for combining RT and 4-1bb therapy in future clinical trials.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Neoplasias/radioterapia , Imunoterapia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral , Ativação Linfocitária , Microambiente Tumoral
7.
Med Care ; 61(5): 288-294, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36917774

RESUMO

BACKGROUND/OBJECTIVE: InFLUenza Patient-reported Outcome (FLU-PRO Plus) is a 34-item patient-reported outcome instrument designed to capture the intensity and frequency of viral respiratory symptoms. This study evaluates whether FLU-PRO Plus responses could discriminate between symptoms of coronavirus disease 2019 (COVID-19) and influenza-like illness (ILI) with no COVID diagnosis, as well as forecast disease progression. METHODS: FLU-PRO Plus was administered daily for 14 days. Exploratory factor analysis was used to reduce the FLU-PRO Plus responses on the first day to 3 factors interpreted as "symptom clusters." The 3 clusters were used to predict COVID-19 versus ILI diagnosis in logistic regression. Correlation between the clusters and quality of life (QoL) measures was used to assess concurrent validity. The timing of self-reported return to usual health in the 14-day period was estimated as a function of the clusters within COVID-19 and ILI groups. RESULTS: Three hundred fourteen patients completed day 1 FLU-PRO Plus, of which 65% had a COVID-19 diagnosis. Exploratory factor analysis identified 3 symptom clusters: (1)general Body, (2) tracheal/bronchial, and (3) nasopharyngeal. Higher nasopharyngeal scores were associated with higher odds of COVID-19 compared with ILI diagnosis [adjusted odds ratio = 1.61 (1.21, 2.12)]. Higher tracheal/bronchial scores were associated with lower odds of COVID-19 [0.58 (0.44, 0.77)]. The 3 symptom clusters were correlated with multiple QoL measures ( r = 0.14-0.56). Higher scores on the general body and tracheal/bronchial symptom clusters were associated with prolonged time to return to usual health [adjusted hazard ratios: 0.76 (0.64, 0.91), 0.80 (0.67, 0.96)]. CONCLUSION: Three symptom clusters identified from FLU-PRO Plus responses successfully discriminated patients with COVID-19 from non-COVID ILI and were associated with QoL and predicted symptom duration.


Assuntos
COVID-19 , Influenza Humana , Humanos , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Qualidade de Vida , Estudos Prospectivos , Estudos de Coortes , Teste para COVID-19 , Síndrome , COVID-19/diagnóstico , COVID-19/epidemiologia , Medidas de Resultados Relatados pelo Paciente , Análise Fatorial
8.
Curr Top Microbiol Immunol ; 435: 107-139, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-31974761

RESUMO

Chikungunya virus (CHIKV) infection in humans is rarely fatal but is often associated with chronic joint and muscle pain. Chronic CHIKV disease is highly debilitating and is associated with viral persistence. To date, there are no approved vaccines or therapeutics to prevent or treat CHIKV infections once they are established. Current palliative treatments aim to reduce joint inflammation and pain associated with acute and chronic CHIKV disease. Development of novel therapeutics that reduces viral loads should positively impact virus inflammatory disease and improve patient outcomes following CHIKV infection. Therapies that target multiple aspects of CHIKV replication cycle should be developed since the virus is capable of rapidly mutating around any single therapeutic. This review summarizes the current status of small molecule inhibitor development against CHIKV.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Vírus , Febre de Chikungunya/tratamento farmacológico , Vírus Chikungunya/genética , Humanos , Replicação Viral
9.
J Gen Intern Med ; 38(6): 1484-1492, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36795328

RESUMO

BACKGROUND: Little is known about whether diabetes increases the risk of COVID-19 infection and whether measures of diabetes severity are related to COVID-19 outcomes. OBJECTIVE: Investigate diabetes severity measures as potential risk factors for COVID-19 infection and COVID-19 outcomes. DESIGN, PARTICIPANTS, MEASURES: In integrated healthcare systems in Colorado, Oregon, and Washington, we identified a cohort of adults on February 29, 2020 (n = 1,086,918) and conducted follow-up through February 28, 2021. Electronic health data and death certificates were used to identify markers of diabetes severity, covariates, and outcomes. Outcomes were COVID-19 infection (positive nucleic acid antigen test, COVID-19 hospitalization, or COVID-19 death) and severe COVID-19 (invasive mechanical ventilation or COVID-19 death). Individuals with diabetes (n = 142,340) and categories of diabetes severity measures were compared with a referent group with no diabetes (n = 944,578), adjusting for demographic variables, neighborhood deprivation index, body mass index, and comorbidities. RESULTS: Of 30,935 patients with COVID-19 infection, 996 met the criteria for severe COVID-19. Type 1 (odds ratio [OR] 1.41, 95% CI 1.27-1.57) and type 2 diabetes (OR 1.27, 95% CI 1.23-1.31) were associated with increased risk of COVID-19 infection. Insulin treatment was associated with greater COVID-19 infection risk (OR 1.43, 95% CI 1.34-1.52) than treatment with non-insulin drugs (OR 1.26, 95% 1.20-1.33) or no treatment (OR 1.24; 1.18-1.29). The relationship between glycemic control and COVID-19 infection risk was dose-dependent: from an OR of 1.21 (95% CI 1.15-1.26) for hemoglobin A1c (HbA1c) < 7% to an OR of 1.62 (95% CI 1.51-1.75) for HbA1c ≥ 9%. Risk factors for severe COVID-19 were type 1 diabetes (OR 2.87; 95% CI 1.99-4.15), type 2 diabetes (OR 1.80; 95% CI 1.55-2.09), insulin treatment (OR 2.65; 95% CI 2.13-3.28), and HbA1c ≥ 9% (OR 2.61; 95% CI 1.94-3.52). CONCLUSIONS: Diabetes and greater diabetes severity were associated with increased risks of COVID-19 infection and worse COVID-19 outcomes.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Adulto , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , COVID-19/epidemiologia , COVID-19/complicações , Fatores de Risco , Diabetes Mellitus Tipo 1/complicações
10.
Gynecol Oncol ; 173: 114-121, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37121178

RESUMO

OBJECTIVE: To demonstrate that shared antibody responses in endometriosis and endometriosis-associated ovarian cancer spontaneously antagonize malignant progression and can be leveraged to develop future immunotherapies. METHODS: B cells from cyopreserved clear cell ovarian carcinoma (CCC, n = 2), endometrioid ovarian carcinoma (EC, n = 2), and endometriomas (n = 2) were isolated, activated, and EBV-immortalized. Antibodies were purified from B cell supernatants and used for screening arrays containing most of the human proteome. Targets were prioritized based on accessibility (transmembrane or secreted proteins), expression in endometriosis and cancer, and concurrent IgA and IgG responses. We focused on antibodies targeting tumor-promoting syndecan binding protein (SDCBP) to demonstrate anti-tumor activity. Immunoblots and qPCR were performed to assess SDCBP expression in ovarian cancer and endometriosis cell lines and tumor samples. Recombinant IgG4 was generated using the variable heavy and light chains of dominant B cell receptors (BCRs) reacting against the extracellular domain of SDCBP, and used in in vivo studies in human CCC- and high-grade serous ovarian carcinoma (HGSOC)-bearing immunodeficient mice. RESULTS: Nine accessible proteins detected by both IgA and IgG were identified in all samples - including SDCBP, which is expressed in ovarian carcinomas of multiple histologies. Administration of α-SDCBP IgG4 in OVCAR3 (HGSOC), TOV21G and RMG-I (CCC) tumor-bearing mice significantly decreased tumor volume compared to control irrelevant IgG4. CONCLUSIONS: Spontaneous antibody responses exert suboptimal but measurable immune pressure against malignant progression in ovarian carcinomas. Using tumor-derived antibodies for developing novel immunotherapeutics warrants further investigation.


Assuntos
Adenocarcinoma de Células Claras , Carcinoma Endometrioide , Endometriose , Neoplasias Ovarianas , Humanos , Feminino , Animais , Camundongos , Neoplasias Ovarianas/patologia , Apoptose , Formação de Anticorpos , Linhagem Celular Tumoral , Carcinoma Epitelial do Ovário , Carcinoma Endometrioide/patologia , Imunoglobulina A/metabolismo , Adenocarcinoma de Células Claras/patologia , Sinteninas/metabolismo
11.
Ann Bot ; 2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38141245

RESUMO

BACKGROUND AND AIMS: Floral volatiles, visual traits, and rewards mediate attraction and defense in plant-pollinator and plant-herbivore interactions, but these floral traits may be altered by global warming through direct effects of temperature or longer term impacts on plant resources. We examined the effect of warming on floral and leaf volatile emissions, floral morphology, plant height, nectar production, and oviposition by seed predators. METHODS: We used open-top chambers that warmed plants in the field +2-3 °C on average (+6-11 °C increase in daily maxima) for 2-4 weeks across 1-3 years at 3 sites in Colorado, USA. Volatiles were sampled from two closely related species of subalpine Ipomopsis with different pollinators: I. aggregata ssp. aggregata, visited mainly by hummingbirds, and I. tenuituba ssp. tenuituba, often visited by hawkmoths. KEY RESULTS: While warming had no detected effects on leaf volatiles, the daytime floral volatiles of both I. aggregata and I. tenuituba responded in subtle ways to warming, with impacts that depended on the species, site, and year. In addition to the long-term effect of warming, temperature at the time of sampling independently affected the floral volatile emissions of I. aggregata during the day and I. tenuituba at night. Warming had little effect on floral morphology for either species, and no effect on nectar concentration, maximum inflorescence height, or flower redness in I. aggregata. However, warming increased nectar production in I. aggregata by 41%, a response that would attract more hummingbird visits, and reduced oviposition by fly seed predators by at least 72%. CONCLUSIONS: Our results suggest that floral traits can show different levels of plasticity to temperature changes in subalpine environments, with potential effects on animal behaviors that help or hinder plant reproduction. They also illustrate the need for more long-term field warming studies, as shown by responses of floral volatiles in different ways to weeks of warming versus temperature at the time of sampling.

12.
Qual Life Res ; 32(6): 1645-1657, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36703019

RESUMO

PURPOSE: A well-defined and reliable patient-reported outcome instrument for COVID-19 is important for assessing symptom severity and supporting research studies. The InFLUenza Patient-Reported Outcome (FLU-PRO) instrument has been expanded to include loss of taste and smell in the FLU-PRO Plus, to comprehensively cover COVID-19 symptoms. Our studies were designed to evaluate and validate the FLU-PRO Plus among patients with COVID-19. METHODS: Two studies were conducted: (1) a qualitative, non-interventional, cross-sectional study of patients with COVID-19 involving hybrid concept elicitation and cognitive debriefing interviews; (2) a psychometric evaluation of the measurement properties of FLU-PRO Plus, using data from COMET-ICE (COVID-19 Monoclonal antibody Efficacy Trial-Intent to Care Early). RESULTS: In the qualitative interviews (n = 30), all 34 items of the FLU-PRO Plus were considered relevant to COVID-19, and participants determined the questionnaire was easily understood, well written, and comprehensive. In the psychometric evaluation (n = 845), the internal consistency reliability of FLU-PRO Plus total score was 0.94, ranging from 0.71 to 0.90 for domain scores. Reproducibility (Day 20-21) was 0.83 for total score, with domain scores of 0.67-0.89. Confirmatory factor analysis with the novel smell/taste domain demonstrated an acceptable fit to the data. CONCLUSION: The content, reliability, validity, and responsiveness of the FLU-PRO Plus in the COVID-19 population were supported. Our results suggest that FLU-PRO Plus is a content- and psychometrically-valid, fit-for-purpose measure which is easily understood by patients. FLU-PRO Plus is a suitable PRO measure for evaluating symptoms of COVID-19 and treatment benefit directly from the patient perspective. TRIAL REGISTRATION: ClinicalTrials.Gov: NCT04545060, September 10, 2020; retrospectively registered.


Assuntos
COVID-19 , Influenza Humana , Humanos , Reprodutibilidade dos Testes , Psicometria , Estudos Transversais , Qualidade de Vida/psicologia , Medidas de Resultados Relatados pelo Paciente , Inquéritos e Questionários
13.
Proc Natl Acad Sci U S A ; 117(28): 16516-16526, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601179

RESUMO

LIN28B is highly expressed in neuroblastoma and promotes tumorigenesis, at least, in part, through inhibition of let-7 microRNA biogenesis. Here, we report that overexpression of either wild-type (WT) LIN28B or a LIN28B mutant that is unable to inhibit let-7 processing increases the penetrance of MYCN-induced neuroblastoma, potentiates the invasion and migration of transformed sympathetic neuroblasts, and drives distant metastases in vivo. Genome-wide chromatin immunoprecipitation coupled with massively parallel DNA sequencing (ChIP-seq) and coimmunoprecipitation experiments show that LIN28B binds active gene promoters in neuroblastoma cells through protein-protein interaction with the sequence-specific zinc-finger transcription factor ZNF143 and activates the expression of downstream targets, including transcription factors forming the adrenergic core regulatory circuitry that controls the malignant cell state in neuroblastoma as well as GSK3B and L1CAM that are involved in neuronal cell adhesion and migration. These findings reveal an unexpected let-7-independent function of LIN28B in transcriptional regulation during neuroblastoma pathogenesis.


Assuntos
Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transativadores/metabolismo , Animais , Animais Geneticamente Modificados , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Neuroblastoma/fisiopatologia , Ligação Proteica , Proteínas de Ligação a RNA/genética , Transativadores/genética , Peixe-Zebra
14.
J Prosthet Dent ; 129(4): 644-649, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34303523

RESUMO

STATEMENT OF PROBLEM: Translucent zirconias have been developed with better esthetics than high-strength zirconias by reducing opacity. However, studies on their translucency and strength are sparse. PURPOSE: The purpose of this in vitro study was to compare the relationship between translucency and biaxial flexural strength of recently developed high-translucency zirconia, high-strength zirconia, and lithium disilicate ceramics. MATERIAL AND METHODS: Disks (n=12) were fabricated for 5 ceramic materials: high-strength zirconia (BruxZir 16 shaded), translucent zirconia (BruxZir Anterior shaded, Katana UTML, Katana STML), and lithium disilicate (IPS e.max, Press HT, and LT). A standard tessellation language (STL) file was designed, and the specimen milled, finished, and glazed according to manufacturer's instructions for each material. The translucency parameter was calculated against black and white backgrounds and white and stump shade with ND4 background by using a spectrophotometer. Biaxial flexural strength was calculated by using the 3-ball test. The load was applied at a crosshead speed of 0.5 mm/min with a 49-N load cell until failure occurred. Translucency parameter and biaxial flexural strength data were analyzed with 1-way analysis of variance (ANOVA). A Tukey honest significant difference multiple comparison test was used to determine significant differences (α=.05). RESULTS: The IPS e.max HT was more translucent against both backgrounds (32.85 for black/white and 15.34 for white/stump), while BruxZir 16 was the least translucent (19.78 for B/W and 8.83 for W/S). All groups tested differed in translucency (P<.001) except for BruxZir Anterior and Katana STML, which were not significantly different (P=.052). For biaxial flexural strength, BruxZir 16 had the highest strength (995.44 MPa) and e.max HT, the lowest (186.75 MPa). No significant differences were found between BruxZir anterior and Katana STML, Katana UTML and IPS e.max LT, or IPS e.max LT and IPS e.max HT (P>.05). Translucency parameter values using both backgrounds were strongly correlated (r=0.99). However, biaxial flexural strength values were inversely related to translucency parameter values when using black/white and white/stump shade but with high correlation (r=-0.777 and -0.756 respectively). CONCLUSIONS: Lithium disilicate was the most translucent and yet the weakest material, whereas high-strength zirconia was the most opaque ceramic and the strongest. Katana UTML had the highest translucency but was weakest among translucent and high-strength zirconia materials. Overall, translucency was negatively correlated with biaxial flexural strength.


Assuntos
Estética Dentária , Resistência à Flexão , Cerâmica , Análise de Variância
15.
New Phytol ; 234(4): 1477-1490, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35274312

RESUMO

Vegetative traits of plants can respond directly to changes in the environment, such as those occurring under climate change. That phenotypic plasticity could be adaptive, maladaptive, or neutral. We manipulated the timing of spring snowmelt and amount of summer precipitation in factorial combination and examined responses of specific leaf area (SLA), trichome density, leaf water content (LWC), photosynthetic rate, stomatal conductance and intrinsic water-use efficiency (iWUE) in the subalpine herb Ipomopsis aggregata. The experiment was repeated in three years differing in natural timing of snowmelt. To examine natural selection, we used survival, relative growth rate, and flowering as fitness indices. A 50% reduction in summer precipitation reduced stomatal conductance and increased iWUE, and doubled precipitation increased LWC. Combining natural and experimental variation, earlier snowmelt reduced soil moisture, photosynthetic rate and stomatal conductance, and increased trichome density and iWUE. Precipitation reduction reversed the mortality selection favoring high stomatal conductance under normal and doubled precipitation, and higher LWC improved growth. Earlier snowmelt is a strong signal of climate change and can change expression of leaf morphology and gas exchange traits, just as reduced precipitation can. Stomatal conductance and SLA showed adaptive plasticity under some conditions.


Assuntos
Adaptação Fisiológica , Folhas de Planta , Mudança Climática , Folhas de Planta/fisiologia , Estações do Ano , Água
16.
Blood ; 135(3): 191-207, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31750881

RESUMO

Protein acetylation is an important contributor to cancer initiation. Histone deacetylase 6 (HDAC6) controls JAK2 translation and protein stability and has been implicated in JAK2-driven diseases best exemplified by myeloproliferative neoplasms (MPNs). By using novel classes of highly selective HDAC inhibitors and genetically deficient mouse models, we discovered that HDAC11 rather than HDAC6 is necessary for the proliferation and survival of oncogenic JAK2-driven MPN cells and patient samples. Notably, HDAC11 is variably expressed in primitive stem cells and is expressed largely upon lineage commitment. Although Hdac11is dispensable for normal homeostatic hematopoietic stem and progenitor cell differentiation based on chimeric bone marrow reconstitution, Hdac11 deficiency significantly reduced the abnormal megakaryocyte population, improved splenic architecture, reduced fibrosis, and increased survival in the MPLW515L-MPN mouse model during primary and secondary transplantation. Therefore, inhibitors of HDAC11 are an attractive therapy for treating patients with MPN. Although JAK2 inhibitor therapy provides substantial clinical benefit in MPN patients, the identification of alternative therapeutic targets is needed to reverse MPN pathogenesis and control malignant hematopoiesis. This study establishes HDAC11 as a unique type of target molecule that has therapeutic potential in MPN.


Assuntos
Hematopoese , Histona Desacetilases/fisiologia , Mutação , Transtornos Mieloproliferativos/patologia , Oncogenes , Animais , Apoptose , Ciclo Celular , Proliferação de Células , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/química , Humanos , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/metabolismo , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Células Tumorais Cultivadas
17.
Glob Chang Biol ; 28(1): 323-339, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34582609

RESUMO

Climate change can cause changes in expression of organismal traits that influence fitness. In flowering plants, floral traits can respond to drought, and that phenotypic plasticity has the potential to affect pollination and plant reproductive success. Global climate change is leading to earlier snow melt in snow-dominated ecosystems as well as affecting precipitation during the growing season, but the effects of snow melt timing on floral morphology and rewards remain unknown. We conducted crossed manipulations of spring snow melt timing (early vs. control) and summer monsoon precipitation (addition, control, and reduction) that mimicked recent natural variation, and examined plastic responses in floral traits of Ipomopsis aggregata over 3 years in the Rocky Mountains. We tested whether increased summer precipitation compensated for earlier snow melt, and if plasticity was associated with changes in soil moisture and/or leaf gas exchange. Lower summer precipitation decreased corolla length, style length, corolla width, sepal width, and nectar production, and increased nectar concentration. Earlier snow melt (taking into account natural and experimental variation) had the same effects on those traits and decreased inflorescence height. The effect of reduced summer precipitation was stronger in earlier snow melt years for corolla length and sepal width. Trait reductions were explained by drier soil during the flowering period, but this effect was only partially explained by how drier soils affected plant water stress, as measured by leaf gas exchange. We predicted the effects of plastic trait changes on pollinator visitation rates, pollination success, and seed production using prior studies on I. aggregata. The largest predicted effect of drier soil on relative fitness components via plasticity was a decrease in male fitness caused by reduced pollinator rewards (nectar production). Early snow melt and reduced precipitation are strong drivers of phenotypic plasticity, and both should be considered when predicting effects of climate change on plant traits in snow-dominated ecosystems.


Assuntos
Polinização , Neve , Ecossistema , Flores , Estações do Ano
18.
Psychother Psychosom ; 91(2): 94-106, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34551415

RESUMO

INTRODUCTION: Emotional dysregulation constitutes a serious public health problem in need of novel transdiagnostic treatments. OBJECTIVE: To this aim, we developed and tested a one-time intervention that integrates behavioral skills training with concurrent repetitive transcranial magnetic stimulation (rTMS). METHODS: Forty-six adults who met criteria for at least one DSM-5 disorder and self-reported low use of cognitive restructuring (CR) were enrolled in a randomized, double-blind, sham-controlled trial that used a between-subjects design. Participants were taught CR and underwent active rTMS applied at 10 Hz over the right (n = 17) or left (n = 14) dorsolateral prefrontal cortex (dlPFC) or sham rTMS (n = 15) while practicing reframing and emotional distancing in response to autobiographical stressors. RESULTS: Those who received active left or active right as opposed to sham rTMS exhibited enhanced regulation (ds = 0.21-0.62) as measured by psychophysiological indices during the intervention (higher high-frequency heart rate variability, lower regulation duration). Those who received active rTMS over the left dlPFC also self-reported reduced distress throughout the intervention (d = 0.30), higher likelihood to use CR, and lower daily distress during the week following the intervention. The procedures were acceptable and feasible with few side effects. CONCLUSIONS: These findings show that engaging frontal circuits simultaneously with cognitive skills training and rTMS may be clinically feasible, well-tolerated and may show promise for the treatment of transdiagnostic emotional dysregulation. Larger follow-up studies are needed to confirm the efficacy of this novel therapeutic approach.


Assuntos
Córtex Pré-Frontal , Estimulação Magnética Transcraniana , Adulto , Terapia de Reestruturação Cognitiva , Método Duplo-Cego , Humanos , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
19.
Am J Bot ; 109(2): 345-360, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35192727

RESUMO

PREMISE: Floral scent is a key aspect of plant reproduction, but its intraspecific variation at multiple scales is poorly understood. Sexual dimorphism and temporal regulation of scent can be shaped by evolution, and interpopulation variation may be a bridge to species differences. We tested whether intraspecific chemical diversity in a wind-pollinated species where selection from biotic pollination is absent is associated with genetic divergence across the Hawaiian archipelago. METHODS: Floral volatiles from females, males, and hermaphrodites of subdioecious Schiedea globosa grown in a common environment from 12 populations were sampled day and night and analyzed by gas chromatography-mass spectrometry. Variation among groups was analyzed by constrained ordination. We also examined the relationships of scent dissimilarity to geographic and genetic distance between populations. RESULTS: Flowers increased total emissions at night through higher emissions of several ketones, oximes, and phenylacetaldehyde. Females emitted less total scent per flower at night but more of some aliphatic compounds than males, and males emitted more ketones and aldoximes. Scent differed among populations during day and night. Divergence in scent produced at night increased with geographic distance within 70-100 km and increased with genetic distance for males during the day and night, but not for females. CONCLUSIONS: Schiedea globosa exhibits diel and sex-based variation in floral scent despite wind pollination and presumed loss of biotic pollination. In males, interpopulation scent differences are correlated with genetic differences, suggesting that scent evolved with dispersal within and across islands.


Assuntos
Polinização , Vento , Animais , Flores/fisiologia , Havaí , Odorantes/análise , Polinização/fisiologia
20.
Nature ; 535(7611): 246-51, 2016 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-27383785

RESUMO

Poor prognosis in neuroblastoma is associated with genetic amplification of MYCN. MYCN is itself a target of let-7, a tumour suppressor family of microRNAs implicated in numerous cancers. LIN28B, an inhibitor of let-7 biogenesis, is overexpressed in neuroblastoma and has been reported to regulate MYCN. Here we show, however, that LIN28B is dispensable in MYCN-amplified neuroblastoma cell lines, despite de-repression of let-7. We further demonstrate that MYCN messenger RNA levels in amplified disease are exceptionally high and sufficient to sponge let-7, which reconciles the dispensability of LIN28B. We found that genetic loss of let-7 is common in neuroblastoma, inversely associated with MYCN amplification, and independently associated with poor outcomes, providing a rationale for chromosomal loss patterns in neuroblastoma. We propose that let-7 disruption by LIN28B, MYCN sponging, or genetic loss is a unifying mechanism of neuroblastoma development with broad implications for cancer pathogenesis.


Assuntos
Amplificação de Genes/genética , MicroRNAs/genética , Neuroblastoma/genética , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Proteínas de Ligação a RNA/genética , Regiões 3' não Traduzidas/genética , Animais , Deleção Cromossômica , Feminino , Deleção de Genes , Genes Neoplásicos/genética , Humanos , Camundongos , MicroRNAs/metabolismo , Modelos Genéticos , Proteína Proto-Oncogênica N-Myc , Neuroblastoma/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
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