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1.
Cell ; 159(5): 1126-1139, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25416950

RESUMO

The MYC oncoproteins are thought to stimulate tumor cell growth and proliferation through amplification of gene transcription, a mechanism that has thwarted most efforts to inhibit MYC function as potential cancer therapy. Using a covalent inhibitor of cyclin-dependent kinase 7 (CDK7) to disrupt the transcription of amplified MYCN in neuroblastoma cells, we demonstrate downregulation of the oncoprotein with consequent massive suppression of MYCN-driven global transcriptional amplification. This response translated to significant tumor regression in a mouse model of high-risk neuroblastoma, without the introduction of systemic toxicity. The striking treatment selectivity of MYCN-overexpressing cells correlated with preferential downregulation of super-enhancer-associated genes, including MYCN and other known oncogenic drivers in neuroblastoma. These results indicate that CDK7 inhibition, by selectively targeting the mechanisms that promote global transcriptional amplification in tumor cells, may be useful therapy for cancers that are driven by MYC family oncoproteins.


Assuntos
Quinases Ciclina-Dependentes/antagonistas & inibidores , Modelos Animais de Doenças , Neuroblastoma/tratamento farmacológico , Proteínas Nucleares/metabolismo , Proteínas Oncogênicas/metabolismo , Fenilenodiaminas/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/uso terapêutico , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quinases Ciclina-Dependentes/metabolismo , Humanos , Proteína Proto-Oncogênica N-Myc , Transcrição Gênica/efeitos dos fármacos , Quinase Ativadora de Quinase Dependente de Ciclina
2.
Bioconjug Chem ; 35(6): 855-866, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38789102

RESUMO

Antibody effector functions including antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis (ADCP) are mediated through the interaction of the antibody Fc region with Fcγ receptors present on immune cells. Several approaches have been used to modulate antibody Fc-Fcγ interactions with the goal of driving an effective antitumor immune response, including Fc point mutations and glycan modifications. However, robust antibody-Fcγ engagement and immune cell binding of Fc-enhanced antibodies in the periphery can lead to the unwanted induction of systemic cytokine release and other dose-limiting infusion-related reactions. Creating a balance between effective engagement of Fcγ receptors that can induce antitumor activity without incurring systemic immune activation is an ongoing challenge in the field of antibody and immuno-oncology therapeutics. Herein, we describe a method for the reversible chemical modulation of antibody-Fcγ interactions using simple poly(ethylene glycol) (PEG) linkers conjugated to antibody interchain disulfides with maleimide attachments. This method enables dosing of a therapeutic with muted Fcγ engagement that is restored in vivo in a time-dependent manner. The technology was applied to an effector function enhanced agonist CD40 antibody, SEA-CD40, and experiments demonstrate significant reductions in Fc-induced immune activation in vitro and in mice and nonhuman primates despite showing retained efficacy and improved pharmacokinetics compared to the parent antibody. We foresee that this simple, modular system can be rapidly applied to antibodies that suffer from systemic immune activation due to peripheral FcγR binding immediately upon infusion.


Assuntos
Receptores de IgG , Animais , Camundongos , Receptores de IgG/imunologia , Humanos , Polietilenoglicóis/química , Citotoxicidade Celular Dependente de Anticorpos , Fagocitose/efeitos dos fármacos
3.
Phys Rev Lett ; 132(4): 041001, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335333

RESUMO

With excellent energy resolution and ultralow-level radiogenic backgrounds, the high-purity germanium detectors in the Majorana Demonstrator enable searches for several classes of exotic dark matter (DM) models. In this work, we report new experimental limits on keV-scale sterile neutrino DM via the transition magnetic moment from conversion to active neutrinos ν_{s}→ν_{a}. We report new limits on fermionic dark matter absorption (χ+A→ν+A) and sub-GeV DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), and new exclusion limits for bosonic dark matter (axionlike particles and dark photons). These searches utilize the (1-100)-keV low-energy region of a 37.5-kg y exposure collected by the Demonstrator between May 2016 and November 2019 using a set of ^{76}Ge-enriched detectors whose surface exposure time was carefully controlled, resulting in extremely low levels of cosmogenic activation.

4.
Nature ; 558(7708): 91-94, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29849150

RESUMO

The axial coupling of the nucleon, gA, is the strength of its coupling to the weak axial current of the standard model of particle physics, in much the same way as the electric charge is the strength of the coupling to the electromagnetic current. This axial coupling dictates the rate at which neutrons decay to protons, the strength of the attractive long-range force between nucleons and other features of nuclear physics. Precision tests of the standard model in nuclear environments require a quantitative understanding of nuclear physics that is rooted in quantum chromodynamics, a pillar of the standard model. The importance of gA makes it a benchmark quantity to determine theoretically-a difficult task because quantum chromodynamics is non-perturbative, precluding known analytical methods. Lattice quantum chromodynamics provides a rigorous, non-perturbative definition of quantum chromodynamics that can be implemented numerically. It has been estimated that a precision of two per cent would be possible by 2020 if two challenges are overcome1,2: contamination of gA from excited states must be controlled in the calculations and statistical precision must be improved markedly2-10. Here we use an unconventional method 11 inspired by the Feynman-Hellmann theorem that overcomes these challenges. We calculate a gA value of 1.271 ± 0.013, which has a precision of about one per cent.

5.
Int J Obes (Lond) ; 47(1): 33-38, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36333585

RESUMO

BACKGROUND: This study examined the relationship among enacted weight stigma, weight self-stigma, and multiple health outcomes. Weight stigma, a stressor experienced across all body sizes, may contribute to poorer physical health outcomes by activating the nervous and endocrine system or by triggering counterproductive health behaviors like lower physical activity, maladaptive eating patterns, and delayed health care, as well as provider bias that may cause a medical concern to be discounted. While associations of weight stigma with mental health issues are well documented, less is known about its association with physical health. METHODS: We enrolled 3821 adults who completed an online survey assessing enacted weight stigma, weight self-stigma, multiple self-reported physical health outcomes, healthcare utilization, and selected health behaviors. RESULTS: After controlling for BMI, health care delay or avoidance, sedentary behavior, and selected demographic characteristics, enacted weight stigma, significantly increased the odds of six physical health problems including hypertension (OR 1.36; CI 1.08, 1.72), hyperglycemia (OR 1.73; CI 1.29, 2.31), thyroid disorder, (OR 1.65; CI 1.27, 2.13), any arthritis (OR 1.70; CI 1.27, 2.26), non-arthritic chronic pain (OR 1.76; CI 1.4, 2.29), and infertility (OR 1.53; CI 1.14, 2.05). Weight self-stigma significantly increased the odds for three physical health problems including hypertension (OR 1.43; CI 1.16, 1.76), hyperglycemia (OR 1.37; CI 1.03, 1.81), and non-arthritic chronic pain (OR 1.5; CI 1.2,1.87). Enacted stigma was associated with more than a four-fold increase in odds of believing that a medical concern was disregarded by a health care provider. CONCLUSIONS: In this study, enacted stigma and weight self-stigma were independently associated with heightened risk for multiple physical health problems, as well as, believing health concerns were discounted by providers. Reducing weight stigma may be an important component of managing multiple physical health conditions.


Assuntos
Dor Crônica , Preconceito de Peso , Adulto , Humanos , Preconceito de Peso/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Estigma Social , Comportamentos Relacionados com a Saúde , Avaliação de Resultados em Cuidados de Saúde
7.
Phys Rev Lett ; 130(26): 261002, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37450817

RESUMO

Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs). Their unique track signature allows a targeted analysis with only 0.05 expected background events from muons. Following unblinding, we observe no signal candidate events. This Letter places strong constraints on spin-independent interactions of dark matter particles with a mass between 1×10^{12} and 2×10^{17} GeV/c^{2}. In addition, we present the first exclusion limits on spin-dependent MIMP-neutron and MIMP-proton cross sections for dark matter particles with masses close to the Planck scale.

8.
Phys Rev Lett ; 130(6): 062501, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36827565

RESUMO

The Majorana Demonstrator searched for neutrinoless double-ß decay (0νßß) of ^{76}Ge using modular arrays of high-purity Ge detectors operated in vacuum cryostats in a low-background shield. The arrays operated with up to 40.4 kg of detectors (27.2 kg enriched to ∼88% in ^{76}Ge). From these measurements, the Demonstrator has accumulated 64.5 kg yr of enriched active exposure. With a world-leading energy resolution of 2.52 keV FWHM at the 2039 keV Q_{ßß} (0.12%), we set a half-life limit of 0νßß in ^{76}Ge at T_{1/2}>8.3×10^{25} yr (90% C.L.). This provides a range of upper limits on m_{ßß} of (113-269) meV (90% C.L.), depending on the choice of nuclear matrix elements.

9.
Phys Rev Lett ; 131(15): 152501, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897780

RESUMO

^{180m}Ta is a rare nuclear isomer whose decay has never been observed. Its remarkably long lifetime surpasses the half-lives of all other known ß and electron capture decays due to the large K-spin differences and small energy differences between the isomeric and lower-energy states. Detecting its decay presents a significant experimental challenge but could shed light on neutrino-induced nucleosynthesis mechanisms, the nature of dark matter, and K-spin violation. For this study, we repurposed the Majorana Demonstrator, an experimental search for the neutrinoless double-beta decay of ^{76}Ge using an array of high-purity germanium detectors, to search for the decay of ^{180m}Ta. More than 17 kg, the largest amount of tantalum metal ever used for such a search, was installed within the ultralow-background detector array. In this Letter, we present results from the first year of Ta data taking and provide an updated limit for the ^{180m}Ta half-life on the different decay channels. With new limits up to 1.5×10^{19} yr, we improved existing limits by 1-2 orders of magnitude which are the most sensitive searches for a single ß and electron capture decay ever achieved. Over all channels, the decay can be excluded for T_{1/2}<0.29×10^{18} yr.

10.
Clin Chem Lab Med ; 61(1): 78-85, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36279170

RESUMO

OBJECTIVES: Vitamin D-binding protein (VDBP), a serum transport protein for 25-hydroxyvitamin D [25(OH)D], has three common proteoforms which have co-localized amino acid variations and glycosylation. A monoclonal immunoassay was found to differentially detect VDBP proteoforms and methods using liquid chromatography-tandem mass spectrometry (LC-MS/MS) might be able to overcome this limitation. Previously developed multiple reaction monitoring LC-MS/MS methods for total VDBP quantification represent an opportunity to probe the potential effects of proteoforms on proteolysis, instrument response and quantification accuracy. METHODS: VDBP was purified from homozygous human donors and quantified using proteolysis or acid hydrolysis and LC-MS/MS. An interlaboratory comparison was performed using pooled human plasma [Standard Reference Material® 1950 (SRM 1950) Metabolites in Frozen Human Plasma] and analyses with different LC-MS/MS methods in two laboratories. RESULTS: Several shared peptides from purified proteoforms were found to give reproducible concentrations [≤2.7% coefficient of variation (CV)] and linear instrument responses (R2≥0.9971) when added to human serum. Total VDBP concentrations from proteolysis or amino acid analysis (AAA) of purified proteoforms had ≤1.92% CV. SRM 1950, containing multiple proteoforms, quantified in two laboratories resulted in total VDBP concentrations with 7.05% CV. CONCLUSIONS: VDBP proteoforms were not found to cause bias during quantification by LC-MS/MS, thus demonstrating that a family of proteins can be accurately quantified using shared peptides. A reference value was assigned for total VDBP in SRM 1950, which may be used to standardize methods and improve the accuracy of VDBP quantification in research and clinical samples.


Assuntos
Espectrometria de Massas em Tandem , Proteína de Ligação a Vitamina D , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Proteólise , Vitamina D , Proteínas Sanguíneas/metabolismo , Aminoácidos/metabolismo
11.
N Engl J Med ; 380(12): 1150-1157, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30893535

RESUMO

A 58-year-old woman with debilitating ankylosing spondylitis who was born to consanguineous parents was found to have an apparent severe vitamin D deficiency that did not respond to supplementation. Liquid chromatography-tandem mass spectrometry showed the absence of circulating vitamin D-binding protein, and chromosomal microarray confirmed a homozygous deletion of the group-specific component (GC) gene that encodes the protein. Congenital absence of vitamin D-binding protein resulted in normocalcemia and a relatively mild disruption of bone metabolism, in this case complicated by severe autoimmune disease. (Funded by the National Institutes of Health and the University of Washington.).


Assuntos
Doenças Autoimunes/complicações , Deleção de Genes , Hidroxicolecalciferóis/sangue , Espondilite Anquilosante/genética , Deficiência de Vitamina D/genética , Proteína de Ligação a Vitamina D/genética , Cálcio/sangue , Cromatografia Líquida , Feminino , Fraturas Espontâneas/etiologia , Expressão Gênica , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Irmãos , Espondilite Anquilosante/complicações , Espectrometria de Massas em Tandem , Vitamina D/metabolismo , Proteína de Ligação a Vitamina D/deficiência
12.
Phys Rev Lett ; 129(16): 161805, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36306777

RESUMO

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3) events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

13.
Phys Rev Lett ; 129(8): 080401, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053678

RESUMO

The Majorana Demonstrator neutrinoless double-beta decay experiment comprises a 44 kg (30 kg enriched in ^{76}Ge) array of p-type, point-contact germanium detectors. With its unprecedented energy resolution and ultralow backgrounds, Majorana also searches for rare event signatures from beyond standard model physics in the low energy region below 100 keV. In this Letter, we test the continuous spontaneous localization (CSL) model, one of the mathematically well-motivated wave function collapse models aimed at solving the long-standing unresolved quantum mechanical measurement problem. While the CSL predicts the existence of a detectable radiation signature in the x-ray domain, we find no evidence of such radiation in the 19-100 keV range in a 37.5 kg-y enriched germanium exposure collected between December 31, 2015, and November 27, 2019, with the Demonstrator. We explored both the non-mass-proportional (n-m-p) and the mass-proportional (m-p) versions of the CSL with two different assumptions: that only the quasifree electrons can emit the x-ray radiation and that the nucleus can coherently emit an amplified radiation. In all cases, we set the most stringent upper limit to date for the white CSL model on the collapse rate, λ, providing a factor of 40-100 improvement in sensitivity over comparable searches. Our limit is the most stringent for large parts of the allowed parameter space. If the result is interpreted in terms of the Diòsi-Penrose gravitational wave function collapse model, the lower bound with a 95% confidence level is almost an order of magnitude improvement over the previous best limit.

14.
Phys Rev Lett ; 129(8): 081803, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053699

RESUMO

Axions were originally proposed to explain the strong-CP problem in QCD. Through axion-photon coupling, the Sun could be a major source of axions, which could be measured in solid state detection experiments with enhancements due to coherent Primakoff-Bragg scattering. The Majorana Demonstrator experiment has searched for solar axions with a set of ^{76}Ge-enriched high purity germanium detectors using a 33 kg-yr exposure collected between January, 2017 and November, 2019. A temporal-energy analysis gives a new limit on the axion-photon coupling as g_{aγ}<1.45×10^{-9} GeV^{-1} (95% confidence level) for axions with mass up to 100 eV/c^{2}. This improves laboratory-based limits between about 1 eV/c^{2} and 100 eV/c^{2}.

15.
Subst Abus ; 43(1): 425-432, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34236297

RESUMO

Background: Criminal problem-solving courts and civil dependency courts often have participants with substance use disorder (SUD), including opioid use disorder (OUD). These courts refer participants to treatment and set treatment-related requirements for court participants to avoid incarceration or to regain custody of children. Medications for opioid use disorder (MOUD) are the most effective treatment for OUD but are underutilized by court system participants. Little is known about variation in court policies for different MOUDs. Also, more information is needed about types of policies for each MOUD, including whether participants may begin MOUD, continue previously begun MOUD, or complete the court program with MOUD. Methods: An online survey was distributed to criminal problem-solving and civil dependency judges in Florida in 2019 and 2020, yielding data from 58 judges (a 24% response rate). We used nonparametric statistics to test hypotheses with ordinal data. A Friedman's test for related samples or Cochran's Q was used to make within-group comparisons between policies and MOUDs. Results: We found considerable policy variation, with more permissive policies for naltrexone than buprenorphine or methadone, and more permissive policies for continuing MOUD than for initiating MOUD or completing a court program with MOUD. For each medication, less than one quarter of judges indicated their court always permits MOUD, with most indicating that MOUD is permitted sometimes or usually. Conclusion: Because respondents rarely chose "never" or "always" for any MOUD policy, most courts appear to be making MOUD decisions on a case-by-case basis. A clearer understanding of this decision-making process is needed. Some court participants may be required to discontinue MOUD before completing a court program, even if they were permitted to start or continue MOUD treatment. Discontinuation of MOUD without medical justification is contrary to the standard of care for individuals with OUD and increases their risk of overdose.


Assuntos
Buprenorfina , Criminosos , Transtornos Relacionados ao Uso de Opioides , Analgésicos Opioides/uso terapêutico , Buprenorfina/uso terapêutico , Criança , Humanos , Metadona/uso terapêutico , Tratamento de Substituição de Opiáceos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/reabilitação , Políticas
16.
Early Child Educ J ; : 1-13, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36597552

RESUMO

Early Childhood Education (ECE) programs provide skills needed for successful kindergarten strides, especially for students from low socioeconomic backgrounds. While Florida's Voluntary Pre-Kindergarten (VPK) program currently serves most four-year-olds, some educators have questioned the program's quality. The purpose of this study was to investigate the direct and indirect effects of Florida's VPK program on kindergarten readiness and academic achievement for students attending the program in one county's VPK (CVPK) when compared to students who did not attend approved VPK programs in this county. The results suggest that, regardless of socioeconomic status, children who attended CVPK programs were just as prepared and performed equally as well in kindergarten as those who did not attend this program. Unfortunately, we cannot know how the CVPK program compared to specific pre-K alternatives without being able to distinguish program attendance across provider types (i.e., other ECE or no pre-K), which is something we recommend Florida begin tracking and make accessible.

17.
Phys Rev Lett ; 126(14): 145001, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33891437

RESUMO

Supermagnetosonic perpendicular flows are magnetically driven by a large radius theta-pinch experiment. Fine spatial resolution and macroscopic coverage allow the full structure of the plasma-piston coupling to be resolved in laboratory experiment for the first time. A moving ambipolar potential is observed to reflect unmagnetized ions to twice the piston speed. Magnetized electrons balance the radial potential via Hall currents and generate signature quadrupolar magnetic fields. Electron heating in the reflected ion foot is adiabatic.

18.
Phys Rev Lett ; 126(9): 091301, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33750173

RESUMO

We report on a search for nuclear recoil signals from solar ^{8}B neutrinos elastically scattering off xenon nuclei in XENON1T data, lowering the energy threshold from 2.6 to 1.6 keV. We develop a variety of novel techniques to limit the resulting increase in backgrounds near the threshold. No significant ^{8}B neutrinolike excess is found in an exposure of 0.6 t×y. For the first time, we use the nondetection of solar neutrinos to constrain the light yield from 1-2 keV nuclear recoils in liquid xenon, as well as nonstandard neutrino-quark interactions. Finally, we improve upon world-leading constraints on dark matter-nucleus interactions for dark matter masses between 3 and 11 GeV c^{-2} by as much as an order of magnitude.

19.
Prev Med ; 150: 106641, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34048822

RESUMO

Assess Ontario's school-based human papillomavirus (HPV) vaccination program on reducing rates of cervical dysplasia, colposcopy services and treatment for genital warts, cervical conization, cryotherapy and laser vaporization of the lower genital tract. Women born in 1995 in Ontario, Canada were the first cohort of students to receive the vaccine. We followed these women from age 18-23 and identified pap test cytology results, referral and attendance at colposcopy, treatment of HPV related warts and treatment of lower-genital tract dysplasia using administrative databases. We compared the incidence of these outcomes to women born in 1985, followed during the same age period prior to access to the HPV vaccine. We calculated relative risk ratios for all outcomes over the 5-year period for the unvaccinated group compared to the vaccinated group. Results were stratified at the income and geographic level. A total of 221,039 women were included. Among vaccinated women, 5.2% percent had cytologic abnormalities and 2.7% required treatment for pre-invasive disease or warts compared to 9.2% and 5.2%, respectively among unvaccinated women. The relative risk of developing a low-grade cytologic abnormality if unvaccinated was 1.69 and 3.74 for high-grade abnormalities. The relative risk of requiring colposcopy if unvaccinated was 1.94 and they were 6.15 times more likely to require treatment. There were no differences between socio-economic groups and geographic regions. Vaccination programs are effective at decreasing rates of cervical dysplasia, lead to reduced need for colposcopy, treatment of HPV related warts and pre-invasive disease even at early ages.


Assuntos
Condiloma Acuminado , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Adolescente , Adulto , Condiloma Acuminado/prevenção & controle , Feminino , Genitália , Humanos , Ontário , Papillomaviridae , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/prevenção & controle , Vacinação , Adulto Jovem
20.
Bioorg Med Chem ; 41: 116189, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34034150

RESUMO

An approach of building block (BB) inclusivity and atom efficient library schemes deliver the quality and diversity of DNA-encoded libraries best suited for small molecule drug discovery. In this Perspective, we offer key learnings in DEL design from a decade's worth of DEL-driven screening.


Assuntos
DNA/química , Desenho de Fármacos , Descoberta de Drogas , Biblioteca Gênica , Bibliotecas de Moléculas Pequenas , Técnicas de Química Combinatória , Replicação do DNA
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