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Charge-transfer emitters are attractive due to their color tunability and potentially high photoluminescence quantum yields (PLQYs). We herein present tetraaminospirenes as donor moieties, which, in combination with a variety of acceptors, furnished 12 charge-transfer emitters with a range of emission colors and PLQYs of up to 99 %. The spatial separation of their frontier molecular orbitals was obtained through careful structural design, and two DA structures were confirmed by X-ray crystallography. A range of photophysical measurements supported by DFT calculations shed light on the optoelectronic properties of this new family of spiro-NN-donor-acceptor dyes.
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The molecular etiology linking the pathogenic mutations in the Huntingtin (Htt) gene with Huntington's disease (HD) is unknown. Prior work suggests a role for Htt in neuronal autophagic function and mutant HTT protein disrupts autophagic cargo loading. Reductions in the bioavailability of the essential metal manganese (Mn) are seen in models of HD. Excess cellular Mn impacts autophagic function, but the target and molecular basis of these changes are unknown. Thus, we sought to determine if changes in cellular Mn status impact autophagic processes in a wild-type or mutant Htt-dependent manner. We report that the HD genotype is associated with reduced Mn-induced autophagy and that acute Mn exposure increases autophagosome induction/formation. To determine if a deficit in bioavailable Mn is mechanistically linked to the autophagy-related HD cellular phenotypes, we examined autophagosomes by electron microscopy. We observed that a 24 h 100 uM Mn restoration treatment protocol attenuated an established HD 'cargo-recognition failure' in the STHdh HD model cells by increasing the percentage of filled autophagosomes. Mn restoration had no effect on HTT aggregate number, but a 72 h co-treatment with chloroquine (CQ) in GFP-72Q-expressing HEK293 cells increased the number of visible aggregates in a dose-dependent manner. As CQ prevents autophagic degradation this indicates that Mn restoration in HD cell models facilitates incorporation of aggregates into autophagosomes. Together, these findings suggest that defective Mn homeostasis in HD models is upstream of the impaired autophagic flux and provide proof-of-principle support for increasing bioavailable Mn in HD to restore autophagic function and promote aggregate clearance.
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Autofagia/efeitos dos fármacos , Doença de Huntington/metabolismo , Manganês/farmacologia , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Células HEK293 , Humanos , Proteína Huntingtina/metabolismo , Proteína Huntingtina/fisiologia , Doença de Huntington/genética , Doença de Huntington/terapia , Células-Tronco Pluripotentes Induzidas , Manganês/metabolismo , Camundongos , Microscopia Eletrônica/métodos , Mutação , Neurônios/metabolismoRESUMO
Alternative metals such as magnesium (Mg) and its alloys have been recently developed for clinical applications such as temporary implants for bone and tissue repair due to their desirable mechanical properties and ability to biodegrade harmlessly in vivo by releasing Mg2+, OH-, and H2 as biodegradation products. The current methods for monitoring in vivo Mg-alloy biodegradation are either invasive and/or costly, complex, or require large equipment and specially trained personnel, thus making real-time and point-of-care monitoring of Mg-alloy implants problematic. Therefore, innovative methods are critically needed. The objective of this research was to develop a novel, thin, and wearable visual H2 sensor prototype for noninvasive monitoring of in vivo Mg-implant biodegradation in medical research and clinical settings with a fast response time. In this work, we successfully demonstrate such a prototype composed of resazurin and catalytic bimetallic gold-palladium nanoparticles (Au-Pd NPs) incorporated into a thin agarose/alginate hydrogel matrix that rapidly changes color from blue to pink upon exposure to various levels of H2 at a constant flow rate. The irreversible redox reactions occurring in the sensor involve H2, in the presence of Au-Pd NPs, converting resazurin to resorufin. To quantify the sensor color changes, ImageJ software was used to analyze photographs of the sensor taken with a smartphone during H2 exposure. The sensor concentration range was from pure H2 down to limits of detection of 6 and 8 µM H2 (defined via two methods). This range is adequate for the intended application of noninvasively monitoring in vivo Mg-alloy implant biodegradation in animals for medical research and patients in clinical settings.
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Magnésio , Nanopartículas Metálicas , Ligas , Animais , Humanos , Hidrogênio , PaládioRESUMO
We exploited the reactivity of an electronically biased Michael acceptor to perform a defluorinative α-arylation reaction using a chiral diene(L*)-rhodium catalyst. Through this methodology, we are able to obtain various secondary amides, containing a tertiary α-stereocenter and a ß,γ-unsaturated gem-difluoro olefin, with excellent enantioselectivities. This methodology addresses the limitations of the previously described α-arylation methods to construct stereo-labile tertiary α-stereocenters. Further investigation of the reaction via inâ situ 19 Fâ NMR monitoring suggests that the formation of the product leads to the inhibition of the active rhodium catalyst.
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Patient-centredness is an accepted term and is perceived by healthcare professionals to be morally and ethically desirable. We are motivated by the belief that this approach will improve the patient-professional experience of the decision-making process and improve health outcomes. We acknowledge that patients, either as participants or as co-investigators, have positive contributions to make to research. As the idiopathic pulmonary fibrosis (IPF) community enters a new era of clinical research activity we consider that there is greater capacity for patient involvement and partnership.Patient involvement in research can be optimised through collaborations in the research design, study conduct, and dissemination. There is increasing interest in using patient- reported outcomes (PROs), such as health-related quality of life, and symptoms measures to inform decision-making and ensure patient perspectives are taken into account. PROs are an essential component of specialist IPF services, to monitor and improve care delivery and to measure and benchmark performance. In clinical trials, PROs can additionally be used to define entry criteria, evaluate efficacy of an intervention, and evaluate adverse events. We suggest that there is a much wider scope for including patient-centred PROs in clinical research and for creative thought in developing patient co-investigator roles.Participation in research activity requires highly refined decision-making processes, particularly in a condition such as IPF, which has an often unpredictable trajectory. The IPF research landscape has changed and the design and conduct of clinical trials in IPF requires some radical rethinking. It is accepted that involving patients in the role of co-investigators will impact the research questions we ask and result in study designs that are patient-centred. IPF clinical trials have been hindered by the lack of availability of validated, disease-specific questionnaires. A conservative approach appears to have been taken to the inclusion of generic symptom or quality of life measures as PRO endpoints. Thus, the impact of new drugs on the quality of life of research participants demonstrates only minimal benefit. It is time to refocus on a patient-centred approach with regards to the co-investigator role, PRO development, and research participants.
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Fibrose Pulmonar Idiopática/terapia , Participação do Paciente/tendências , Projetos de Pesquisa/tendências , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida , Inquéritos e QuestionáriosRESUMO
Biological complexity and the need for highly differentiated medicines means that drug discovery and development have become increasingly challenging and expensive. Thus, new paradigms for research and drug development need to be created that bring together a wide array of expertise. One potential solution is collaboration between bio-pharma and academic research centres. Two examples are discussed, one with a large pharma company (GlaxoSmithKline) and the other a small biotech (Genoa Pharmaceuticals). Patient advocacy organization can also have role in assisting in the creation of these partnerships by informing patients of ongoing research and clinical trials, and supporting the development of networks that can provide major benefit for both basic research and drug development. A major 'hurdle' for the creation of these relationships is the issue of intellectual property. Examples are provided of how this issue can be resolved.
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Associações de Consumidores , Comportamento Cooperativo , Indústria Farmacêutica , Defesa do Paciente , Universidades , Descoberta de Drogas/economia , HumanosRESUMO
Previously designed flow cytometry panels have provided a framework to analyze T-cell activation; however, few provide an extensive view of lymphocyte populations, and none are optimized for murine models. This article describes a panel designed specifically to assess the expression of activation and exhaustion markers in expanding lymphocyte populations in tumor-bearing mice across two distinct genetic backgrounds: BALB/c and C57BL/6. This comprehensive panel enables the assessment of multiple functional states and immune checkpoint markers across cytotoxic CD8+ T cells, helper and regulatory CD4+ T cells and natural killer cells in murine whole blood, lymph nodes and tumor.
Flow cytometry is a technique that allows researchers to analyze protein expression on single cells through the detection of fluorescence markers that is widely used to assess immune cell phenotypes. The selection of target proteins expressed on specific cell subsets and accompanying fluorophores is known as 'panel building' and is critically important for accurate flow cytometry results. However, there is a lack of optimized and reproducible panels for mouse models of cancer. This article describes the development and performance of a robust panel that characterizes immune cell diversity and activation, while leaving room for customization. This flow cytometry panel provides a starting point for exploring the spectrum of mouse lymphocyte activation and is adaptable for subsequent studies.
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Linfócitos T CD8-Positivos , Ativação Linfocitária , Camundongos , Animais , Citometria de Fluxo , Camundongos Endogâmicos C57BL , Subpopulações de Linfócitos , BiomarcadoresRESUMO
PURPOSE: To investigate the prevalence of vaccine hesitancy among black college students and to explain students' reasoning behind their vaccine hesitancy. DESIGN: online survey completed in spring and summer of 2021. Students were recruited via email. SETTING: HBCU campus, North Carolina, USA. SUBJECTS: 397 currently enrolled students. MEASURES: An original survey instrument was developed which included questions on vaccination status and plans to get vaccinated, perceived threat from the coronavirus (adopted from PEW research) exercise behaviors and demographics. Respondents were also given the chance to respond to an open-ended question about their feelings about the vaccine. ANALYSIS: Binary Logistic Regression predicting likelihood that respondent is vaccine hesitant. RESULTS: Confidence in the safety of the vaccine was the strongest predictor of vaccine hesitancy. At the time of the survey only 25% of students had received at least one dose of the vaccine. 37% of the students did not plan on ever getting vaccinated. Other considerations (living with a vulnerable person or concerns about their own vulnerability to COVID) were not associated with getting vaccinated. Students were particularly concerned about side effects from the vaccine. CONCLUSION: Racial disparities in COVID-19 infections, deaths, and vaccinations serve as a stark reminder of the urgent need to better understand the factors that could lead to mitigation of the virus. Fear about the safety of the vaccine among minority populations in particular must be unpacked in order to address valid concerns and overcome hesitancy. This study provides key insights into the contours of those fears.
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Although Black men in the United States face high rates of hypertension, the nexus of health and religion remain understudied for this population. The present study analyzes religious variables, such as prayer, Bible reading, and religious meditation, to describe the frequency of these practices among hypertensive and non-hypertensive Black men. This study utilizes data from the Midlife in the United States (MIDUS) 3 - Milwaukee African American Sample series, with 135 Black men (51.1% stating that they had experienced hypertension in the past 12 months). Findings suggest that Black men with a diagnosis of hypertension were significantly more likely to report that they prayed and read religious literature more often than their non-hypertensive counterparts. The results of the present study demonstrate key religious practices that hypertensive Black men might use as a potential coping response to their health condition.
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BACKGROUND: Tumor cell death caused by radiation therapy (RT) triggers antitumor immunity in part because dying cells release adjuvant factors that amplify and sustain dendritic cell and T cell responses. We previously demonstrated that bempegaldesleukin (BEMPEG: NKTR-214, an immunostimulatory IL-2 cytokine prodrug) significantly enhanced the antitumor efficacy of RT through a T cell-dependent mechanism. Because RT can induce either immunogenic or tolerogenic cell death, depending on various factors (radiation dose, cell cycle phase), we hypothesized that providing a specific immunogenic adjuvant, like intratumoral therapy with a novel toll-like receptor (TLR) 7/8 agonist, NKTR-262, would improve systemic tumor-specific responses through the activation of local innate immunity. Therefore, we evaluated whether intratumoral NKTR-262 combined with systemic BEMPEG treatment would elicit improved tumor-specific immunity and survival compared with RT combined with BEMPEG. METHODS: Tumor-bearing mice (CT26; EMT6) received BEMPEG (0.8 mg/kg; intravenously), RT (12 Gy × 1), and/or intratumoral NKTR-262 (0.5 mg/kg). Flow cytometry was used to evaluate CD4+ and CD8+ T cell responses in the blood and tumor 7 days post-treatment. The contribution of specific immune subsets was determined by depletion of CD4+, CD8+, or NK cells. CD8+ T cell cytolytic activity was determined by an in vitro CTL assay. Data are representative of 1-2 independent experiments (n=5-14/group) and statistical significance was determined by 1-way analysis of variance (ANOVA) or repeated measures ANOVA (p value cut-off of 0.05). RESULTS: BEMPEG+NKTR-262 significantly improved survival compared with BEMPEG+RT in a CD8+ T cell-dependent manner. Response to BEMPEG+NKTR-262 was characterized by a significant expansion of activated CD8+ T cells (GzmA+; Ki-67+; ICOS+; PD-1+) in the blood, which correlated with reduced tumor size (p<0.05). In the tumor, BEMPEG+NKTR-262 induced higher frequencies of GzmA+ CD8+ T cells exhibiting reduced expression of suppressive molecules (PD-1+), compared with BEMPEG+RT (p<0.05). Further, BEMPEG+NKTR-262 treatment induced greater tumor-specific CD8+ T cell cytolytic function than BEMPEG+RT. CONCLUSIONS: BEMPEG+NKTR-262 therapy elicited more robust expansion of activated CD8+ T cells compared with BEMPEG+RT, suggesting that intratumoral TLR stimulation provides superior antigen presentation and costimulatory activity compared with RT. A clinical trial of BEMPEG+NKTR-262 for patients with metastatic solid tumors is in progress (NCT03435640).
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Neoplasias , Receptor 7 Toll-Like , Adjuvantes Imunológicos/metabolismo , Animais , Linfócitos T CD8-Positivos , Ensaios Clínicos como Assunto , Humanos , Imunoterapia , Interleucina-2 , Camundongos , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/metabolismoRESUMO
This work presents 4 open source potentiostat solutions for performing accurate measurements in cyclic voltammetry and square wave voltammetry at a low price. A very simple and easy to reproduce analogic board (c.a. 10 ) was driven either by a Teensy card from the company PJRC under an Arduino/Python software solution (39 ) or by an Analog Discovery 2 device from Digilent (less than 300 ). A smartphone Bluetooth Android interface was also created to circumvent the use of a computer. We demonstrated that our scheme is suitable for measurements in classical electrochemical conditions but also to carry out experiments with ultramicroelectrodes. We could thus reach a noise resolution of less than 1 pA. Scan rates of 8000 Vs-1 with ohmic drop compensation were also achieved. The device is suitable for teaching purposes but also for experiments in a participative science context on the ground, or countries with lower financial possibilities.
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The Microfluidic Optical Stretcher (MOS) has previously been shown to be a versatile tool to measure mechanical properties of single suspended cells. In this study we combine optical stretching and fluorescent calcium imaging. A cell line transfected with a heat sensitive cation channel was used as a model system to show the versatility of the setup. The cells were loaded with the Ca(2+) dye Fluo-4 and imaged with confocal laser scanning microscopy while being stretched. During optical stretching heat is transferred to the cell causing a pronounced Ca(2+) influx through the cation channel. The technique opens new perspectives for investigating the role of Ca(2+) in regulating cell mechanical behavior.
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Cálcio/análise , Rim/química , Microscopia Confocal/instrumentação , Células Cultivadas , Humanos , Rim/citologiaRESUMO
Optical traps such as tweezers and stretchers are widely used to probe the mechanical properties of cells. Beyond their large range of applications, the use of infrared laser light in optical traps causes significant heating effects in the cell. This study investigated the effect of laser-induced heating on cell viability. Common viability assays are not very sensitive to damages caused in short periods of time or are not practicable for single cell analysis. We used cell spreading, a vital ability of cells, as a new sensitive viability marker. The optical stretcher, a two beam laser trap, was used to simulate heat shocks that cells typically experience during measurements in optical traps. The results show that about 60% of the cells survived heat shocks without vital damage at temperatures of up to 58 ± 2°C for 0.5 s. By varying the duration of the heat shocks, it was shown that 60% of the cells stayed viable when exposed to 48 ± 2°C for 5 s.
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Temperatura Alta/efeitos adversos , Lasers/efeitos adversos , Análise de Célula Única , Absorção , Animais , Tamanho Celular/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Resposta ao Choque Térmico/efeitos da radiação , Camundongos , Células NIH 3T3RESUMO
This work deals with the design of a high sensitivity DNA sequence detector using a 50 MHz quartz crystal microbalance (QCM) electronic oscillator circuit. The oscillator circuitry is based on Miller topology, which is able to work in damping media. Calibration and experimental study of frequency noise are carried out, finding that the designed sensor has a resolution of 7.1 ng/cm(2) in dynamic conditions (with circulation of liquid). Then the oscillator is proved as DNA biosensor. Results show that the system is able to detect the presence of complementary target DNAs in a solution with high selectivity and sensitivity. DNA target concentrations higher of 50 ng/mL can be detected.
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Técnicas Biossensoriais , DNA/análise , Técnicas de Microbalança de Cristal de Quartzo , Técnicas Biossensoriais/métodos , Calibragem , DNA/química , Dissulfetos/química , Eletroquímica/métodos , Eletrônica , Desenho de Equipamento , Oscilometria/métodos , Física/métodos , Reprodutibilidade dos TestesRESUMO
Research has shown elevated rates of diet-related health problems in Detroit, Michigan compared to state and national averages. Using 47 in-depth interviews of African American residents in two Detroit neighborhoods, I examine the interplay between agency and social structure in food acquisition. Participants discussed numerous difficulties obtaining food, including availability, cost, quality, and accessibility. Residents employed many strategies to address these issues, including carefully examining food before purchase, sharing transportation to leave the neighborhood, and using multiple sources. However, the potential to pursue food acquisition strategies varied, in part, according to community contextual factors, including resident concerns about safety, the availability of food banks, and resources in surrounding areas. Nutritional knowledge among participants was sophisticated, suggesting that health education efforts, as opposed to addressing lack of access to high-quality food, might be misguided. I found that accounting for both agency and structural context aids in understanding diet-related behaviors.
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Comportamento Alimentar , Abastecimento de Alimentos/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Características de Residência/estatística & dados numéricos , Adolescente , Adulto , Negro ou Afro-Americano , Tomada de Decisões , Feminino , Comportamentos Relacionados com a Saúde , Educação em Saúde , Promoção da Saúde , Humanos , Entrevista Psicológica , Masculino , Desnutrição , Michigan , Inquéritos Nutricionais , Estado Nutricional , Pobreza , Marketing Social , Gravação em Fita , Adulto JovemRESUMO
Early reports of COVID-19 often inaccurately presented the virus as a serious concern only among older adults. On the social media platform of Twitter, #BoomerRemover originated as a hashtag intended to express the age-related disparities of COVID-19. This study used a content analysis to examine tweets over a two-week period in March 2020 that used #BoomerRemover to discuss COVID-19 among older adults. A total of 1875 tweets were analyzed. Salient themes include: (1) There's a Real Intergenerational Divide, (2) Young People are Affected Too, (3) It's Being Used for Political Gain, and (4) #BoomerRemover is Simply Disrespectful. Findings suggest that many of the tweets employing #BoomerRemover were grounded in either personal or political ageism. In addition, a significant portion of tweeters used #BoomerRemover to defend older adults and speak out against ageism. This study highlights the importance of recognizing and addressing the growing intergenerational divide on social media, particularly during the COVID-19 pandemic.
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Etarismo/psicologia , Etarismo/estatística & dados numéricos , COVID-19/psicologia , Mídias Sociais/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Humanos , Pessoa de Meia-Idade , SARS-CoV-2 , Adulto JovemRESUMO
BACKGROUND: High-dose radiotherapy (RT) is known to be immunogenic, but is rarely capable of driving clinically relevant abscopal antitumor immunity as monotherapy. RT is known to increase antigen presentation, type I/II interferon responses, and immune cell trafficking to irradiated tumors. Bempegaldesleukin (NKTR-214) is a CD122-preferential interleukin 2 (IL-2) pathway agonist that has been shown to increase tumor-infiltrating lymphocytes, T cell clonality, and increase PD-1 expression. NKTR-214 has increased drug half-life, decreased toxicity, and increased CD8+ T cell and natural killer cell stimulation compared with IL-2. METHODS: Animals bearing bilateral subcutaneous MCA-205 fibrosarcoma or CT26 colorectal tumors were treated with NKTR-214, RT, or combination therapy, and tumor growth of irradiated and abscopal lesions was assessed. Focal RT was delivered using a small animal radiation research platform. Peripheral and tumor-infiltrating immune phenotype and functional analyses were performed by flow cytometry. RNA expression profiling from both irradiated and abscopal lesions was performed using microarray. RESULTS: We demonstrate synergy between RT of a single tumor and NKTR-214 systemic therapy resulting in dramatically increased cure rates of mice bearing bilateral tumors compared with RT or NKTR-214 therapy alone. Combination therapy resulted in increased magnitude and effector function of tumor-specific CD8+ T cell responses and increased trafficking of these T cells to both irradiated and distant, unirradiated, tumors. CONCLUSIONS: Given the increasing role of hypofractionated and stereotactic body RT as standard of care treatments in the management of locally advanced and metastatic cancer, these data have important implications for future clinical trial development. The combination of RT and NKTR-214 therapy potently stimulates systemic antitumor immunity and should be evaluated for the treatment of patients with locally advanced and metastatic solid tumors.