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1.
Opt Express ; 31(20): 32619-32636, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859061

RESUMO

We present a study on the optical losses of Fabry-Pérot cavities subject to realistic transverse mirror misalignment. We consider mirrors of the two most prevalent surface forms: idealised spherical depressions, and Gaussian profiles generated by laser ablation. We first describe the mode mixing phenomena seen in the spherical mirror case and compare to the frequently-used clipping model, observing close agreement in the predicted diffraction loss, but with the addition of protective mode mixing at transverse degeneracies. We then discuss the Gaussian mirror case, detailing how the varying surface curvature across the mirror leads to complex variations in round trip loss and mode profile. In light of the severe mode distortion and strongly elevated loss predicted for many cavity lengths and transverse alignments when using Gaussian mirrors, we suggest that the consequences of mirror surface profile are carefully considered when designing cavity experiments.

3.
J Biol Chem ; 296: 100787, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34015332

RESUMO

The dopamine transporter (DAT) is essential for the reuptake of the released neurotransmitter dopamine (DA) in the brain. Psychostimulants, methamphetamine and cocaine, have been reported to induce the formation of DAT multimeric complexes in vivo and in vitro. The interpretation of DAT multimer function has been primarily in the context of compounds that induce structural and functional modifications of the DAT, complicating the understanding of the significance of DAT multimers. To examine multimerization in the absence of DAT ligands as well as in their presence, we developed a novel, optogenetic fusion chimera of cryptochrome 2 and DAT with an mCherry fluorescent reporter (Cry2-DAT). Using blue light to induce Cry2-DAT multimeric protein complex formation, we were able to simultaneously test the functional contributions of DAT multimerization in the absence or presence of substrates or inhibitors with high spatiotemporal precision. We found that blue light-stimulated Cry2-DAT multimers significantly increased IDT307 uptake and MFZ 9-18 binding in the absence of ligands as well as after methamphetamine and nomifensine treatment. Blue light-induced Cry2-DAT multimerization increased colocalization with recycling endosomal marker Rab11 and had decreased presence in Rab5-positive early endosomes and Rab7-positive late endosomes. Our data suggest that the increased uptake and binding results from induced and rapid trafficking of DAT multimers to the plasma membrane. Our data suggest that DAT multimers may function to help maintain DA homeostasis.


Assuntos
Membrana Celular/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Dopamina/metabolismo , Animais , Transporte Biológico , Membrana Celular/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Expressão Gênica , Células HEK293 , Humanos , Neurônios/metabolismo , Optogenética , Multimerização Proteica
4.
Rev Sci Instrum ; 92(3): 033205, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33820060

RESUMO

We present a design for an atomic oven suitable for loading ion traps, which is operated via optical heating with a continuous-wave multimode diode laser. The absence of the low-resistance electrical connections necessary for Joule heating allows the oven to be extremely well thermally isolated from the rest of the vacuum system. Extrapolating from high-flux measurements of an oven filled with calcium, we calculate that a target region number density of 100 cm-3, suitable for rapid ion loading, will be produced with 175(10) mW of heating laser power, limited by radiative losses. With simple feedforward to the laser power, the turn-on time for the oven is 15 s. Our measurements indicate that an oven volume 1000 times smaller could still hold enough source metal for decades of continuous operation.

5.
Magn Reson Imaging ; 80: 90-97, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33901585

RESUMO

PURPOSE: Hepatic thermal ablation therapy can result in c-Met-mediated off-target stimulation of distal tumor growth. The purpose of this study was to determine if a similar effect on tumor metabolism could be detected in vivo with hyperpolarized 13C MRI. MATERIALS AND METHODS: In this prospective study, female Fisher rats (n = 28, 120-150 g) were implanted with R3230 rat breast adenocarcinoma cells and assigned to either: sham surgery, hepatic radiofrequency ablation (RFA), or hepatic RFA + adjuvant c-Met inhibition with PHA-665752 (RFA + PHA). PHA-665752 was administered at 0.83 mg/kg at 24 h post-RFA. Tumor growth was measured daily. MRI was performed 24 h before and 72 h after treatment on 14 rats, and the conversion of 13C-pyruvate into 13C-lactate within each tumor was quantified as lactate:pyruvate ratio (LPR). Comparisons of tumor growth and LPR were performed using paired and unpaired t-tests. RESULTS: Hepatic RFA alone resulted in increased growth of the distant tumor compared to sham treatment (0.50 ± 0.13 mm/day versus 0.11 ± 0.07 mm/day; p < 0.001), whereas RFA + PHA (0.06 ± 0.13 mm/day) resulted in no significant change from sham treatment (p = 0.28). A significant increase in LPR was seen following hepatic RFA (+0.016 ± 0.010, p = 0.02), while LPR was unchanged for sham treatment (-0.048 ± 0.051, p = 0.10) or RFA + PHA (0.003 ± 0.041, p = 0.90). CONCLUSION: In vivo hyperpolarized 13C MRI can detect hepatic RFA-induced increase in lactate flux within a distant R3230 tumor, which correlates with increased tumor growth. Adjuvant inhibition of c-Met suppresses these off-target effects, supporting a role for the HGF/c-Met signaling axis in these tumorigenic responses.


Assuntos
Ablação por Cateter , Neoplasias Hepáticas , Neoplasias , Animais , Feminino , Fígado/diagnóstico por imagem , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos Prospectivos , Ratos
6.
J Radiol Case Rep ; 15(2): 25-34, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33717408

RESUMO

Hemorrhagic cholecystitis is a potentially deadly and difficult to recognize entity. It is associated with cystic artery pseudoaneurysm and is usually seen in the setting of acute calculous cholecystitis. We report two cases of hemorrhagic cholecystitis with arteriographic findings of cystic artery pseudoaneurysms that were successfully embolized using microcoils, facilitating subsequent cholecystectomy. Both cases had unusual presentations of gallbladder rupture with hemoperitoneum, the latter of which was atypical occurring in the absence of gallstones. We believe when hemorrhagic cholecystitis is suspected, a two-step therapeutic approach should be employed with embolization of the bleeding cystic artery followed by cholecystectomy. A comprehensive literature review and discussion of hemorrhagic cholecystitis will be provided.


Assuntos
Colecistite Aguda/diagnóstico por imagem , Hemoperitônio/diagnóstico por imagem , Idoso , Angiografia , Colecistectomia , Colecistite Aguda/terapia , Embolização Terapêutica , Hemoperitônio/terapia , Humanos , Masculino
7.
AJR Am J Roentgenol ; 217(5): 1141-1152, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33594907

RESUMO

BACKGROUND. Primary colon cancer location affects survival of patients with metastatic colorectal cancer (mCRC). Outcomes based on primary tumor location after salvage hepatic radioembolization with 90Y resin microspheres are not well studied. OBJECTIVE. The objectives of this study are to assess the survival outcomes of patients with advanced chemorefractory mCRC treated with 90Y radioembolization, as stratified by primary tumor location, and to explore potential factors that are predictive of survival. METHODS. A total of 99 patients who had progressive mCRC liver metastases while receiving systemic therapy and who were treated with 90Y radioembolization at a single center were retrospectively analyzed. For 89 patients, tumor response on the first imaging follow-up examination (CT or MRI performed at a mean [± SD] of 1.9 ± 0.9 months after 90Y radioembolization) was evaluated using RECIST. Overall survival (OS), OS after 90Y radioembolization, and hepatic progression-free survival (PFS) were calculated using the Kaplan-Meier method. Outcomes and associations of outcomes with tumor response were compared between patients with left- and right-sided tumors. RESULTS. A total of 74 patients had left-sided colon cancer, and 25 patients had right-sided colon cancer. Median OS from the time of mCRC diagnosis was 37.2 months, median OS after 90Y radioembolization was 5.8 months, and median hepatic PFS was 3.3 months. Based on RECIST, progressive disease on first imaging follow-up was observed in 38 patients (43%) after 90Y radioembolization and was associated with shorter OS after 90Y radioembolization compared with observation of disease control on first imaging follow-up (4.0 vs 10.5 months; p < .001). Patients with right-sided primary tumors showed decreased median OS after 90Y radioembolization compared with patients with left-sided primary tumors (5.4 vs 6.2 months; p = .03). Right- and left-sided primary tumors showed no significant difference in RECIST tumor response, hepatic PFS, or extrahepatic disease progression (p > .05). Median survival after 90Y radioembolization was significantly lower among patients with progressive disease than among those with disease control in the group with left-sided primary tumors (4.2 vs 13.9 months; p < .001); however, this finding was not observed in the group with right-sided primary tumors (3.3 vs 7.2 months; p = .05). CONCLUSION. Right-sided primary tumors were independently associated with decreased survival among patients with chemorefractory mCRC after 90Y radioembolization, despite these patients having a similar RECIST tumor response, hepatic PFS, and extrahepatic disease progression compared with patients with left-sided primary tumors. CLINICAL IMPACT. Primary colon cancer location impacts outcomes after salvage 90Y radioembolization and may help guide patient selection.


Assuntos
Neoplasias Colorretais/patologia , Embolização Terapêutica/métodos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Terapia de Salvação/métodos , Radioisótopos de Ítrio/uso terapêutico , Idoso , Neoplasias Colorretais/mortalidade , Embolização Terapêutica/efeitos adversos , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Critérios de Avaliação de Resposta em Tumores Sólidos , Terapia de Salvação/efeitos adversos
8.
Magn Reson Imaging ; 77: 169-179, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33388362

RESUMO

INTRODUCTION: Quantitative MRI (qMRI) parameters have been increasingly used to develop predictive models to accurately monitor treatment response in prostate cancer after radiotherapy. To reliably detect changes in signal due to treatment response, predictive models require qMRI parameters with high repeatability and reproducibility. The purpose of this study was to measure qMRI parameter uncertainties in both commercial and in-house developed phantoms to guide the development of robust predictive models for monitoring treatment response. MATERIALS AND METHODS: ADC, T1, and R2* values were acquired across three 3 T scanners with a prostate-specific qMRI protocol using the NIST/ISMRM system phantom, RSNA/NIST diffusion phantom, and an in-house phantom. A B1 field map was acquired to correct for flip angle inhomogeneity in T1 maps. All sequences were repeated in each scan to assess within-session repeatability. Weekly scans were acquired on one scanner for three months with the in-house phantom. Between-session repeatability was measured with test-retest scans 6-months apart on all scanners with all phantoms. Accuracy, defined as percentage deviation from reference value for ADC and T1, was evaluated using the system and diffusion phantoms. Repeatability and reproducibility coefficients of variation (%CV) were calculated for all qMRI parameters on all phantoms. RESULTS: Overall, repeatability CV of ADC was <2.40%, reproducibility CV was <3.98%, and accuracy ranged between -8.0% to 2.7% across all scanners. Applying B1 correction on T1 measurements significantly improved the repeatability and reproducibility (p<0.05) but increased error in accuracy (p<0.001). Repeatability and reproducibility of R2* was <4.5% and <7.3% respectively in the system phantom across all scanners. CONCLUSION: Repeatability, reproducibility, and accuracy in qMRI parameters from a prostate-specific protocol was estimated using both commercial and in-house phantoms. Results from this work will be used to identify robust qMRI parameters for use in the development of predictive models to longitudinally monitor treatment response for prostate cancer in current and future clinical trials.


Assuntos
Biomarcadores Tumorais/metabolismo , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/metabolismo , Humanos , Masculino , Imagens de Fantasmas , Reprodutibilidade dos Testes
9.
BMC Pulm Med ; 20(1): 234, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867730

RESUMO

BACKGROUND: Cystic Fibrosis (CF) is a hereditary pulmonary and extra-pulmonary disease that occurs equally in men and women. However, a difference in morbidity and mortality rates between the sexes has been long documented. Similarly, a sex-disparity in disease severity has been reported in asthma as well. Studies done to date point to estrogen as a possible cause of this sex disparity in pulmonary outcomes in both conditions. CASE PRESENTATION: Here, we describe a case of a patient with CF and asthma/allergic bronchopulmonary aspergillosis (ABPA) undergoing sex reassignment therapy (male-to-female) and the negative impact it had on her lung function and frequency of pulmonary exacerbations in the context of increasing doses of exogenous estrogen. CONCLUSIONS: This case raises the possibility of a link between estrogen and worsening pulmonary outcomes and the need for further studies into transgender individuals with CF and/or asthma/ABPA as well as those undergoing high dose estrogen therapy for other indications.


Assuntos
Aspergilose Broncopulmonar Alérgica/complicações , Asma/complicações , Fibrose Cística/complicações , Estrogênios/efeitos adversos , Pulmão/fisiopatologia , Aspergilose Broncopulmonar Alérgica/fisiopatologia , Asma/fisiopatologia , Fibrose Cística/fisiopatologia , Estrogênios/administração & dosagem , Feminino , Humanos , Masculino , Testes de Função Respiratória , Cirurgia de Readequação Sexual , Pessoas Transgênero , Adulto Jovem
10.
Phys Rev Lett ; 124(11): 110501, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32242699

RESUMO

We demonstrate remote entanglement of trapped-ion qubits via a quantum-optical fiber link with fidelity and rate approaching those of local operations. Two ^{88}Sr^{+} qubits are entangled via the polarization degree of freedom of two spontaneously emitted 422 nm photons which are coupled by high-numerical-aperture lenses into single-mode optical fibers and interfere on a beam splitter. A novel geometry allows high-efficiency photon collection while maintaining unit fidelity for ion-photon entanglement. We generate heralded Bell pairs with fidelity 94% at an average rate 182 s^{-1} (success probability 2.18×10^{-4}).

11.
Phys Rev Lett ; 123(11): 110503, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31573247

RESUMO

Robust qubit memory is essential for quantum computing, both for near-term devices operating without error correction, and for the long-term goal of a fault-tolerant processor. We directly measure the memory error ε_{m} for a ^{43}Ca^{+} trapped-ion qubit in the small-error regime and find ε_{m}<10^{-4} for storage times t≲50 ms. This exceeds gate or measurement times by three orders of magnitude. Using randomized benchmarking, at t=1 ms we measure ε_{m}=1.2(7)×10^{-6}, around ten times smaller than that extrapolated from the T_{2}^{*} time, and limited by instability of the atomic clock reference used to benchmark the qubit.

12.
J Intellect Disabil Res ; 63(8): 947-956, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30775832

RESUMO

BACKGROUND: Tuberous sclerosis complex (TSC) is a complex multisystem genetic disorder. Approximately 84% of people with TSC have epilepsy. However, there is little literature available regarding families' experiences with TSC and seizure management. Therefore, the aim of the current study was to explore families' positive and negative experiences, and attitudes towards TSC, epilepsy and medical management of seizures. METHODS: Framework analysis informed an open exploration of families' experiences with TSC, epilepsy and medical management of seizures. Using structured interviews, 11 parents of people with TSC and 2 people with TSC were interviewed, providing the data set for transcription and thematic analysis. RESULTS: 'TSC rules our life' overarched three subordinate themes: 'Our normal', 'Burnout' and 'Seizure management has given us our life back'. Families had to adapt to the normality of needing to constantly supervise their child even as they become an adult. They express a feeling of fear particularly of seizures, and this has impact throughout the family. There are frequent expressions of exhaustion and struggling to fight for access and support. There are some positives and cautious hope with the gaining of control from seizures as being able to predict or plan improves activity and participation. These interviews provided a rich insight into the lives of those with TSC and their families. CONCLUSION: There are exciting developments with respect to scientific understanding of the pathophysiology of TSC, which opens opportunity for new treatments. Holistic family centred health care and practical support (e.g. opportunities for parental respite) is as important as medical intervention. As TSC is such a complex condition, there is a need for specialist clinics and TSC-specific research.


Assuntos
Epilepsia/tratamento farmacológico , Família/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Esclerose Tuberosa/terapia , Adolescente , Adulto , Criança , Gerenciamento Clínico , Epilepsia/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Esclerose Tuberosa/complicações , Adulto Jovem
13.
Carcinogenesis ; 40(8): 998-1009, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-30590459

RESUMO

The epidermal growth factor receptor (EGFR) is a major oncogene in triple-negative breast cancer (TNBC), but the use of EGFR-targeted tyrosine kinase inhibitors (TKI) and therapeutic monoclonal antibodies is associated with poor response and acquired resistance. Understanding the basis for the acquired resistance to these drugs and identifying biomarkers to monitor the ensuing resistance remain a major challenge. We previously showed that reduced expression of annexin A6 (AnxA6), a calcium-dependent membrane-binding tumor suppressor, not only promoted the internalization and degradation of activated EGFR but also sensitized TNBC cells to EGFR-TKIs. Here, we demonstrate that prolong (>3 days) treatment of AnxA6-low TNBC cells with lapatinib led to AnxA6 upregulation and accumulation of cholesterol in late endosomes. Basal extracellular signal-regulated kinase 1 and 2 (ERK1/2) activation was EGFR independent and significantly higher in lapatinib-resistant MDA-MB-468 (LAP-R) cells. These cells were more sensitive to cholesterol depletion than untreated control cells. Inhibition of lapatinib-induced upregulation of AnxA6 by RNA interference (A6sh) or withdrawal lapatinib from LAP-R cells not only reversed the accumulation of cholesterol in late endosomes but also led to enrichment of plasma membranes with cholesterol, restored EGFR-dependent activation of ERK1/2 and sensitized the cells to lapatinib. These data suggest that lapatinib-induced AnxA6 expression and accumulation of cholesterol in late endosomes constitute an adaptive mechanism for EGFR-expressing TNBC cells to overcome prolong treatment with EGFR-targeted TKIs and can be exploited as an option to inhibit and/or monitor the frequently observed acquired resistance to these drugs.


Assuntos
Anexina A6/genética , Lapatinib/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lapatinib/efeitos adversos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
14.
Proc Biol Sci ; 285(1891)2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30464064

RESUMO

The power of citizen science to contribute to both science and society is gaining increased recognition, particularly in physics and biology. Although there is a long history of public engagement in agriculture and food science, the term 'citizen science' has rarely been applied to these efforts. Similarly, in the emerging field of citizen science, most new citizen science projects do not focus on food or agriculture. Here, we convened thought leaders from a broad range of fields related to citizen science, agriculture, and food science to highlight key opportunities for bridging these overlapping yet disconnected communities/fields and identify ways to leverage their respective strengths. Specifically, we show that (i) citizen science projects are addressing many grand challenges facing our food systems, as outlined by the United States National Institute of Food and Agriculture, as well as broader Sustainable Development Goals set by the United Nations Development Programme, (ii) there exist emerging opportunities and unique challenges for citizen science in agriculture/food research, and (iii) the greatest opportunities for the development of citizen science projects in agriculture and food science will be gained by using the existing infrastructure and tools of Extension programmes and through the engagement of urban communities. Further, we argue there is no better time to foster greater collaboration between these fields given the trend of shrinking Extension programmes, the increasing need to apply innovative solutions to address rising demands on agricultural systems, and the exponential growth of the field of citizen science.


Assuntos
Agricultura/tendências , Participação da Comunidade , Alimentos , Pesquisa/tendências , Agricultura/normas , Pesquisa/normas , Estados Unidos
15.
Sci Rep ; 8(1): 8812, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29891956

RESUMO

The association between mucosal microbiota and HIV-1 infection has garnered great attention in the field of HIV-1 research. Previously, we reported a receptor-independent HIV-1 entry into epithelial cells mediated by a Gram-negative invasive bacterium, Porphyromonas gingivalis. Here, we present evidence showing that P. gingivalis outer membrane vesicles (OMVs) promote mucosal transmission of HIV-1. We demonstrated, using the Dynabeads technology, a specific interaction between HIV-1 and P. gingivalis OMVs which led to an OMV-dependent viral entry into oral epithelial cells. HIV-1 was detected in human oral keratinocytes (HOKs) after a 20 minute exposure to the HIV-vesicle complexes. After entry, most of the complexes appeared to dissociate, HIV-1 was reverse-transcribed, and viral DNA was integrated into the genome of HOKs. Meanwhile, some of the complexes exited the original host and re-entered neighboring HOKs and permissive cells of HIV-1. Moreover, P. gingivalis vesicles enhanced HIV-1 infection of MT4 cells at low infecting doses that are not able to establish an efficient infection alone. These findings suggest that invasive bacteria and their OMVs with ability to interact with HIV-1 may serve as a vehicle to translocate HIV through the mucosa, establish mucosal transmission of HIV-1, and enhance HIV-1 infectivity.


Assuntos
Transmissão de Doença Infecciosa , Células Epiteliais/virologia , Vesículas Extracelulares/metabolismo , Infecções por HIV/transmissão , HIV-1/fisiologia , Porphyromonas gingivalis/metabolismo , Internalização do Vírus , Células Cultivadas , Humanos , Modelos Teóricos
16.
Rev Sci Instrum ; 89(5): 053102, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29864886

RESUMO

Ion traps are often loaded from atomic beams produced by resistively heated ovens. We demonstrate an atomic oven which has been designed for fast control of the atomic flux density and reproducible construction. We study the limiting time constants of the system and, in tests with 40Ca, show that we can reach the desired level of flux in 12 s, with no overshoot. Our results indicate that it may be possible to achieve an even faster response by applying an appropriate one-off heat treatment to the oven before it is used.

17.
Cell Physiol Biochem ; 47(2): 800-816, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29807365

RESUMO

BACKGROUND/AIMS: Nuclear factor erythroid 2-related factor 2 (Nrf2) is a basic leucine-zipper transcription factor essential for cellular responses to oxidative stress. Degradation of Nrf2 in the cytoplasm, mediated by Keap1-Cullin3/RING box1 (Cul3-Rbx1) E3 ubiquitin ligase and the proteasome, is considered the primary pathway controlling the cellular abundance of Nrf2. Although the nucleus has been implicated in the degradation of Nrf2, little information is available on how this compartment participates in degrading Nrf2. METHODS: Here, we fused the photoconvertible fluorescent protein Dendra2 to Nrf2 and capitalized on the irreversible change in color (green to red) that occurs when Dendra2 undergoes photoconversion to study degradation of Dendra2-Nrf2 in single live cells. RESULTS: Using this approach, we show that the half-life (t1/2) of Dendra2-Nrf2 in the whole cell, under homeostatic conditions, is 35 min. Inhibition of the proteasome with MG-132 or induction of oxidative stress with tert-butylhydroquinone (tBHQ) extended the half-life of Dendra2-Nrf2 by 6- and 28-fold, respectively. By inhibiting nuclear export using Leptomycin B, we provide direct evidence that degradation of Nrf2 also occurs in the nucleus and involves PML-NBs (Promyelocytic Leukemia-nuclear bodies). We further demonstrate that co-expression of Dendra2-Nrf2 and Crimson-PML-I lacking two PML-I sumoylation sites (K65R and K490R) changed the decay rate of Dendra2-Nrf2 in the nucleus and stabilized the nuclear derived Nrf2 levels in whole cells. CONCLUSION: Altogether, our findings provide direct evidence for degradation of Nrf2 in the nucleus and suggest that modification of Nrf2 in PML nuclear bodies contributes to its degradation in intact cells.


Assuntos
Núcleo Celular/metabolismo , Proteínas Luminescentes/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteína da Leucemia Promielocítica/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Ácidos Graxos Insaturados/farmacologia , Meia-Vida , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Leupeptinas/farmacologia , Luz , Proteínas Luminescentes/genética , Camundongos , Microscopia de Fluorescência , Fator 2 Relacionado a NF-E2/genética , Nordefrin/análogos & derivados , Nordefrin/farmacologia , Proteínas Nucleares/metabolismo , Proteína da Leucemia Promielocítica/genética , Estabilidade Proteica/efeitos dos fármacos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Sumoilação
18.
Chemistry ; 24(36): 8985-8988, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29679472

RESUMO

This study reports the synthesis and testing of a family of rhodamine pro-fluorophores and an enzyme capable of converting pro-fluorophores to Rhodamine 110. We prepared a library of simple N,N'-diacyl rhodamines and investigated porcine liver esterase (PLE) as an enzyme to activate rhodamine-based pro-fluorophores. A PLE-expressing cell line generated an increase in fluorescence rapidly upon pro-fluorophore addition demonstrating the rhodamine pro-fluorophores are readily taken up and fluorescent upon PLE-mediated release. Rhodamine pro-fluorophore amides trifluoroacetamide (TFAm) and proponamide (PAm) appeared to be the best substrates using a cell-based assay using PLE expressing HEK293. Our pro-fluorophore series showed diffusion into live cells and resisted endogenous hydrolysis. The use of our engineered cell line containing the exogenous enzyme PLE demonstrated the rigorousness of amide masking when compared to cells not containing PLE. This simple and selective pro-fluorophore rhodamine pair with PLE offers the potential to be used in vitro and in vivo fluorescence based assays.


Assuntos
Esterases/metabolismo , Fígado/enzimologia , Rodaminas/metabolismo , Animais , Esterases/química , Esterases/genética , Células HEK293 , Humanos , Microscopia Confocal , Rodaminas/química , Espectrometria de Fluorescência , Suínos
19.
Child Care Health Dev ; 44(2): 195-202, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28809057

RESUMO

BACKGROUND: Standing frames are used for children with cerebral palsy (CP). They may improve body structure and function (e.g., reducing risk of hip subluxation, and improving bladder and bowel function), improving activity (e.g., motor abilities) and participation (e.g., interaction with peers), but there is little evidence that they do. We aimed to identify current UK standing frame practice for children with CP and to understand stakeholder views regarding their clinical benefits and challenges to use. METHOD: Three populations were sampled: clinicians prescribing standing frames for children with CP (n = 305), professionals (health and education) working with children with CP who use standing frames (n = 155), and parents of children with CP who have used standing frames (n = 91). Questionnaires were developed by the co-applicant group and piloted with other professionals and parents of children with CP. They were distributed online via clinical and parent networks across the UK. RESULTS: Prescribing practice was consistent, but achieving the prescribed use was not always possible. Respondents in all groups reported the perceived benefits of frames, which include many domains of the International Classification of Functioning Disability and Health for Children and Youth. Challenges of use are related to physical space and child-reported pain. CONCLUSIONS: These survey findings provide information from key stakeholders regarding current UK standing frame practice.


Assuntos
Paralisia Cerebral/reabilitação , Tecnologia Assistiva , Atividades Cotidianas , Adolescente , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Criança , Pré-Escolar , Pesquisas sobre Atenção à Saúde , Humanos , Lactente , Pais/psicologia , Postura , Prática Profissional/estatística & dados numéricos
20.
Child Care Health Dev ; 44(2): 203-211, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29168216

RESUMO

BACKGROUND: Consensus opinion supports standing frame use as part of postural management for nonambulant young people with cerebral palsy. Although the rationale for standing frame use and the associated challenges have been described, little attention has been given to the users' experiences. The aim of the current study was to explore young people's positive and negative experiences, and attitudes regarding standing frame use. METHODS: Framework analysis informed an open exploration of young people's opinions of standing frames. Using semistructured interviews, 12 young people with cerebral palsy (6 female) were interviewed, providing the data set for transcription and thematic analysis. FINDINGS: The first theme "attitudes to standing frames" describes the young people's understanding of why they use standing frames. Although standing frames can be painful, some young people believe they should be endured to improve their body structure and function. There were mixed views about the impact standing frames have socially, with some young people feeling excluded from their peers, and others feeling as though standing frames helped them "fit in." Some young people are not offered a choice about how and when they use their standing frame. The second theme "challenges of standing frame use" highlights the issues with standing frame use such as manual handling, interference from siblings, and the lack of aesthetically pleasing standing frame designs. CONCLUSIONS: Young people report benefits related to choice, pain relief, and participation but can also cause pain, discomfort, and reduced independence and participation. Healthcare professionals should have open, informative conversations about potential benefits and challenges of standing frames on all aspects of the young people's lives, including participation and activity.


Assuntos
Atitude Frente a Saúde , Paralisia Cerebral/reabilitação , Tecnologia Assistiva , Adolescente , Paralisia Cerebral/fisiopatologia , Criança , Inglaterra , Desenho de Equipamento , Feminino , Humanos , Relações Interpessoais , Entrevistas como Assunto , Masculino , Dor/etiologia , Jogos e Brinquedos , Postura , Pesquisa Qualitativa , Tecnologia Assistiva/efeitos adversos
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