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1.
Cell ; 172(1-2): 262-274.e11, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29328915

RESUMO

Arc/Arg3.1 is required for synaptic plasticity and cognition, and mutations in this gene are linked to autism and schizophrenia. Arc bears a domain resembling retroviral/retrotransposon Gag-like proteins, which multimerize into a capsid that packages viral RNA. The significance of such a domain in a plasticity molecule is uncertain. Here, we report that the Drosophila Arc1 protein forms capsid-like structures that bind darc1 mRNA in neurons and is loaded into extracellular vesicles that are transferred from motorneurons to muscles. This loading and transfer depends on the darc1-mRNA 3' untranslated region, which contains retrotransposon-like sequences. Disrupting transfer blocks synaptic plasticity, suggesting that transfer of dArc1 complexed with its mRNA is required for this function. Notably, cultured cells also release extracellular vesicles containing the Gag region of the Copia retrotransposon complexed with its own mRNA. Taken together, our results point to a trans-synaptic mRNA transport mechanism involving retrovirus-like capsids and extracellular vesicles.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Produtos do Gene gag/genética , Corpos Multivesiculares/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Terminações Pré-Sinápticas/metabolismo , RNA Mensageiro/metabolismo , Animais , Transporte Biológico , Células Cultivadas , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Drosophila , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Produtos do Gene gag/química , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Junção Neuromuscular/metabolismo , Plasticidade Neuronal , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Terminações Pré-Sinápticas/fisiologia , Ligação Proteica , Domínios Proteicos , Retroelementos/genética
2.
Nature ; 586(7828): 228-231, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33028998

RESUMO

Annular structures (rings and gaps) in disks around pre-main-sequence stars have been detected in abundance towards class II protostellar objects that are approximately 1,000,000 years old1. These structures are often interpreted as evidence of planet formation1-3, with planetary-mass bodies carving rings and gaps in the disk4. This implies that planet formation may already be underway in even younger disks in the class I phase, when the protostar is still embedded in a larger-scale dense envelope of gas and dust5. Only within the past decade have detailed properties of disks in the earliest star-forming phases been observed6,7. Here we report 1.3-millimetre dust emission observations with a resolution of five astronomical units that show four annular substructures in the disk of the young (less than 500,000 years old)8 protostar IRS 63. IRS 63 is a single class I source located in the nearby Ophiuchus molecular cloud at a distance of 144 parsecs9, and is one of the brightest class I protostars at millimetre wavelengths. IRS 63 also has a relatively large disk compared to other young disks (greater than 50 astronomical units)10. Multiple annular substructures observed towards disks at young ages can act as an early foothold for dust-grain growth, which is a prerequisite of planet formation. Whether or not planets already exist in the disk of IRS 63, it is clear that the planet-formation process begins in the initial protostellar phases, earlier than predicted by current planet-formation theories11.

4.
Ann Surg ; 279(2): 231-239, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37916404

RESUMO

OBJECTIVE: To create a blueprint for surgical department leaders, academic institutions, and funding agencies to optimally support surgeon-scientists. BACKGROUND: Scientific contributions by surgeons have been transformative across many medical disciplines. Surgeon-scientists provide a distinct approach and mindset toward key scientific questions. However, lack of institutional support, pressure for increased clinical productivity, and growing administrative burden are major challenges for the surgeon-scientist, as is the time-consuming nature of surgical training and practice. METHODS: An American Surgical Association Research Sustainability Task Force was created to outline a blueprint for sustainable science in surgery. Leaders from top NIH-sponsored departments of surgery engaged in video and in-person meetings between January and April 2023. A strength, weakness, opportunities, threats analysis was performed, and workgroups focused on the roles of surgeons, the department and institutions, and funding agencies. RESULTS: Taskforce recommendations: (1) SURGEONS: Growth mindset : identifying research focus, long-term planning, patience/tenacity, team science, collaborations with disparate experts; Skill set : align skills and research, fill critical skill gaps, develop team leadership skills; DEPARTMENT OF SURGERY (DOS): (2) MENTORSHIP: Chair : mentor-mentee matching/regular meetings/accountability, review of junior faculty progress, mentorship training requirement, recognition of mentorship (eg, relative value unit equivalent, awards; Mentor: dedicated time, relevant scientific expertise, extramural funding, experience and/or trained as mentor, trusted advisor; Mentee : enthusiastic/eager, proactive, open to feedback, clear about goals; (3) FINANCIAL SUSTAINABILITY: diversification of research portfolio, identification of matching funding sources, departmental resource awards (eg, T-/P-grants), leveraging of institutional resources, negotiation of formalized/formulaic funds flow investment from academic medical center toward science, philanthropy; (4) STRUCTURAL/STRATEGIC SUPPORT: Structural: grants administrative support, biostats/bioinformatics support, clinical trial and research support, regulatory support, shared departmental laboratory space/equipment; Strategic: hiring diverse surgeon-scientist/scientists faculty across DOS, strategic faculty retention/ recruitment, philanthropy, career development support, progress tracking, grant writing support, DOS-wide research meetings, regular DOS strategic research planning; (5) COMMUNITY AND CULTURE: Community: right mix of faculty, connection surgeon with broad scientific community; Culture: building research infrastructure, financial support for research, projecting importance of research (awards, grand rounds, shoutouts); (6) THE ROLE OF INSTITUTIONS: Foundation: research space co-location, flexible start-up packages, courses/mock study section, awards, diverse institutional mentorship teams; Nurture: institutional infrastructure, funding (eg, endowed chairs), promotion friendly toward surgeon-scientists, surgeon-scientists in institutional leadership positions; Expectations: RVU target relief, salary gap funding, competitive starting salaries, longitudinal salary strategy; (7) THE ROLE OF FUNDING AGENCIES: change surgeon research training paradigm, offer alternate awards to K-awards, increasing salary cap to reflect market reality, time extension for surgeon early-stage investigator status, surgeon representation on study section, focused award strategies for professional societies/foundations. CONCLUSIONS: Authentic recommitment from surgeon leaders with intentional and ambitious actions from institutions, corporations, funders, and society is essential in order to reap the essential benefits of surgeon-scientists toward advancements of science.


Assuntos
Pesquisa Biomédica , Cirurgiões , Humanos , Estados Unidos , Mentores , Docentes , Centros Médicos Acadêmicos , Mobilidade Ocupacional , National Institutes of Health (U.S.)
5.
Ann Surg Oncol ; 31(7): 4487-4497, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38557909

RESUMO

BACKGROUND: Radioactive tracer injections for breast cancer sentinel lymph node mapping can be painful. In this randomized trial, we compared four approaches to topical pain control for radiotracer injections. METHODS: Breast cancer patients were randomized (9 April 2021-8 May 2022) to receive the institutional standard of ice prior to injection (n = 44), or one of three treatments: ice plus a vibrating distraction device (Buzzy®; n = 39), 4% lidocaine patch (n = 44), or 4% lidocaine patch plus ice plus Buzzy® (n = 40). Patients completed the Wong-Baker FACES® pain score (primary outcome) and a satisfaction with pain control received scale (secondary). Nuclear medicine technologists (n = 8) rated perceived pain control and ease of administration for each patient. At study conclusion, technologists rank-ordered treatments. Data were analyzed as intention-to-treat. Wilcoxon rank-sum tests were used to compare pain scores of control versus pooled treatment arms (primary) and then control to each treatment arm individually (secondary). RESULTS: There were no differences in pain scores between the control and treatment groups, both pooled and individually. Eighty-five percent of patients were 'satisfied/very satisfied' with treatment received, with no differences between groups. No differences in providers' perceptions of pain were observed, although providers perceived treatments involving Buzzy© more difficult to administer (p < 0.001). Providers rated lidocaine patch as the easiest, with ice being second. CONCLUSION: In this randomized trial, no differences in patient-reported pain or satisfaction with treatment was observed between ice and other topical treatments. Providers found treatments using Buzzy® more difficult to administer. Given patient satisfaction and ease of administration, ice is a reasonable standard.


Assuntos
Anestésicos Locais , Neoplasias da Mama , Lidocaína , Manejo da Dor , Humanos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Pessoa de Meia-Idade , Manejo da Dor/métodos , Lidocaína/administração & dosagem , Anestésicos Locais/administração & dosagem , Linfonodo Sentinela/patologia , Compostos Radiofarmacêuticos/administração & dosagem , Idoso , Biópsia de Linfonodo Sentinela/métodos , Adulto , Seguimentos , Prognóstico , Gelo , Medição da Dor , Dor/etiologia , Dor/prevenção & controle , Dor/tratamento farmacológico , Administração Tópica
6.
Ann Surg Oncol ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825628

RESUMO

BACKGROUND: The 8th edition American Joint Committee on Cancer staging system combined anatomic stage (AS) with receptor status and grade to create prognostic stage (PS). PS has been validated in single-institution and cancer registry studies; however, missing human epidermal growth factor receptor 2 (HER2) status and variable treatment and follow-up create limitations. OBJECTIVE: Our objective was to compare the relative prognostic ability of PS versus AS to predict survival using breast cancer clinical trial data. METHODS: Women with non-metastatic breast cancer enrolled in six Alliance for Clinical Trials in Oncology trials were included (enrollment years 1997-2010). AS and PS were constructed using pathological tumor size, nodal status, estrogen receptor (ER), progesterone receptor (PR), HER2 status, and grade. Unadjusted Cox proportional hazard models were estimated to predict overall survival within 5 years, with AS and PS as predictor variables. The relative predictive power of staging models was assessed by comparing Harrell concordance indices (C-indices). Kaplan-Meier-based mortality estimates were compared by stage. RESULTS: Overall, 6924 women were included (median age 53 years); 45.2% were diagnosed with ER+/PR+/HER2- tumors, 26.2% with HER2+ tumors, and 17.1% with ER-/PR-/HER2- tumors. Median follow-up time was 5 years (interquartile range 2.95-5.00). PS significantly improved predictive performance (C-index 0.721) for overall survival compared with AS (0.700) (p = 0.020). Kaplan-Meier hazard estimates suggested PS did not distinguish mortality risk between patients with IIB and IIIA or IB and IIA disease. CONCLUSIONS: PS has significantly improved predictive performance for OS compared with AS. As systemic therapies evolve, it will be important to re-evaluate the prognostic staging system, particularly for patients with intermediate-stage cancers. CLINICALTRIALS: gov Identifier: NCT02171078.

7.
PLoS Genet ; 17(1): e1009287, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33465062

RESUMO

Huntington's disease is a progressive autosomal dominant neurodegenerative disorder caused by the expansion of a polyglutamine tract at the N-terminus of a large cytoplasmic protein. The Drosophila huntingtin (htt) gene is widely expressed during all developmental stages from embryos to adults. However, Drosophila htt mutant individuals are viable with no obvious developmental defects. We asked if such defects could be detected in htt mutants in a background that had been genetically sensitized to reveal cryptic developmental functions. Amyloid precursor protein (APP) is linked to Alzheimer's disease. Appl is the Drosophila APP ortholog and Appl signaling modulates axon outgrowth in the mushroom bodies (MBs), the learning and memory center in the fly, in part by recruiting Abl tyrosine kinase. Here, we find that htt mutations suppress axon outgrowth defects of αß neurons in Appl mutant MB by derepressing the activity of Abl. We show that Abl is required in MB αß neurons for their axon outgrowth. Importantly, both Abl overexpression and lack of expression produce similar phenotypes in the MBs, indicating the necessity of tightly regulating Abl activity. We find that Htt behaves genetically as a repressor of Abl activity, and consistent with this, in vivo FRET-based measurements reveal a significant increase in Abl kinase activity in the MBs when Htt levels are reduced. Thus, Appl and Htt have essential but opposing roles in MB development, promoting and suppressing Abl kinase activity, respectively, to maintain the appropriate intermediate level necessary for axon growth.


Assuntos
Aciltransferases/genética , Axônios/metabolismo , Proteínas de Drosophila/genética , Proteína Huntingtina/genética , Doença de Huntington/genética , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Transporte Axonal/genética , Axônios/patologia , Drosophila melanogaster/genética , Desenvolvimento Embrionário/genética , Humanos , Doença de Huntington/patologia , Aprendizagem/fisiologia , Memória/fisiologia , Corpos Pedunculados/crescimento & desenvolvimento , Corpos Pedunculados/patologia , Mutação/genética , Degeneração Neural/genética , Degeneração Neural/patologia , Neurônios/metabolismo , Neurônios/patologia , Transdução de Sinais/genética
8.
Hong Kong Med J ; 30(2): 94-101, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38577838

RESUMO

INTRODUCTION: Early identification and initiation of reperfusion therapy is essential for suspected acute ischaemic stroke. A pre-hospital stroke notification (PSN) protocol using FASE (facial drooping, arm weakness, speech difficulties, and eye palsy) was implemented to improve key performance indicators (KPIs) in acute stroke care delivery. We assessed KPIs and clinical outcomes before and after PSN implementation in Hong Kong. METHODS: This prospective cohort study with historical controls was conducted in the Accident and Emergency Departments of four public hospitals in Hong Kong. Patients were screened using the PSN protocol between August 2021 and February 2022. Suspected stroke patients between August 2020 and February 2021 were included as historical controls. Door-to-needle (DTN) and door-to-computed tomography (DTC) times before and after PSN implementation were compared. Clinical outcomes including National Institutes of Health Stroke Scale score at 24 hours and modified Rankin Scale score at 3 months after intravenous recombinant tissue-type plasminogen activator (IV-rtPA) were also assessed. RESULTS: Among the 715 patients (266 PSN and 449 non-PSN) included, 50.8% of PSN patients and 37.7% of non-PSN patients had a DTC time within 25 minutes (P<0.001). For the 58 PSN and 134 non-PSN patients given IV-rtPA, median DTN times were 67 and 75.5 minutes, respectively (P=0.007). The percentage of patients with a DTN time within 60 minutes was higher in the PSN group than in the non-PSN group (37.9% vs 21.6%; P=0.019). No statistically significant differences in clinical outcomes were observed. CONCLUSION: Although the PSN protocol shortened DTC and DTN times, clinical outcomes did not significantly differ.

9.
New Phytol ; 240(3): 1305-1326, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37678361

RESUMO

Pollen and tracheophyte spores are ubiquitous environmental indicators at local and global scales. Palynology is typically performed manually by microscopic analysis; a specialised and time-consuming task limited in taxonomical precision and sampling frequency, therefore restricting data quality used to inform climate change and pollen forecasting models. We build on the growing work using AI (artificial intelligence) for automated pollen classification to design a flexible network that can deal with the uncertainty of broad-scale environmental applications. We combined imaging flow cytometry with Guided Deep Learning to identify and accurately categorise pollen in environmental samples; here, pollen grains captured within c. 5500 Cal yr BP old lake sediments. Our network discriminates not only pollen included in training libraries to the species level but, depending on the sample, can classify previously unseen pollen to the likely phylogenetic order, family and even genus. Our approach offers valuable insights into the development of a widely transferable, rapid and accurate exploratory tool for pollen classification in 'real-world' environmental samples with improved accuracy over pure deep learning techniques. This work has the potential to revolutionise many aspects of palynology, allowing a more detailed spatial and temporal understanding of pollen in the environment with improved taxonomical resolution.


Assuntos
Aprendizado Profundo , Inteligência Artificial , Citometria de Fluxo , Filogenia , Pólen
10.
Opt Express ; 31(4): 5767-5776, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823849

RESUMO

The temporal modulation of an electron bunch train accelerated from a foil target irradiated by an intense laser pulse is studied by measuring the coherent transition radiation (CTR) from the rear surface of a target. We experimentally obtained CTR spectra from a 1 µm thick foil target irradiated at a maximum intensity of 6.5 × 1019 W/cm2. Spectral redshifts of the emitted radiation corresponding to increases in laser intensity were observed. These measurements were compared with the theoretical calculation of CTR spectra considering ultrafast surface dynamics, such as plasma surface oscillation and relativistically induced transparency. Plasma surface oscillations induce a spectral redshift, while relativistic transparency causes a spectral blueshift. Both effects are required to find reasonable agreement with the experiment over the entire range of laser intensities.

11.
PLoS Biol ; 18(11): e3000791, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33232312

RESUMO

Small island developing states in the Caribbean are among the most vulnerable countries on the planet to climate variability and climate change. In the last 3 decades, the Caribbean region has undergone frequent and intense heat waves, storms, floods, and droughts. This has had a detrimental impact on population health and well-being, including an increase in infectious disease outbreaks. Recent advances in climate science have enhanced our ability to anticipate hydrometeorological hazards and associated public health challenges. Here, we discuss progress towards bridging the gap between climate science and public health decision-making in the Caribbean to build health system resilience to extreme climatic events. We focus on the development of climate services to help manage mosquito-transmitted disease epidemics. There are numerous areas of ongoing biological research aimed at better understanding the direct and indirect impacts of climate change on the transmission of mosquito-borne diseases. Here, we emphasise additional factors that affect our ability to operationalise this biological understanding. We highlight a lack of financial resources, technical expertise, data sharing, and formalised partnerships between climate and health communities as major limiting factors to developing sustainable climate services for health. Recommendations include investing in integrated climate, health and mosquito surveillance systems, building regional and local human resource capacities, and designing national and regional cross-sectoral policies and national action plans. This will contribute towards achieving the Sustainable Development Goals (SDGs) and maximising regional development partnerships and co-benefits for improved health and well-being in the Caribbean.


Assuntos
Surtos de Doenças/prevenção & controle , Doenças Transmitidas por Vetores/epidemiologia , Doenças Transmitidas por Vetores/transmissão , Animais , Região do Caribe/epidemiologia , Mudança Climática , Surtos de Doenças/economia , Resistência à Doença/genética , Resistência à Doença/fisiologia , Vetores de Doenças , Secas , Política de Saúde/tendências , Humanos , Saúde Pública/métodos , Saúde Pública/tendências
12.
Radiographics ; 43(10): e220151, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37676826

RESUMO

Breast imaging radiologists regularly perform image-guided biopsies of suspicious breast lesions based on features that are associated with a likelihood of malignancy ranging from 2% to greater than 95% (Breast Imaging Reporting and Data System categories 4 and 5). As diagnostic partners, pathologists perform histopathologic assessment of these tissue samples to confirm a diagnosis. Correlating the imaging findings with the histopathologic results is an integral aspect of multidisciplinary breast care. Assessment of radiologic-pathologic concordance is vital in guiding appropriate management, as it enables identification of discordant results, minimizing the chance of misdiagnosis. Undersampling can lead to false-negative results, with the frequencies of false-negative diagnoses varying on the basis of multiple factors, including biopsy type (eg, core needle, vacuum-assisted needle), needle gauge, and type of lesion sampled at biopsy (ie, mass, calcifications, asymmetry, architectural distortion). Improving a radiologist's knowledge of macroscopic and microscopic breast anatomy and more common breast diseases and their expected imaging findings ensures more accurate radiologic-pathologic correlation and management recommendations. The histopathologic and molecular characteristics of biopsy-sampled breast lesions aid in making an accurate diagnosis. Hematoxylin-eosin staining provides critical morphologic details, whereas immunohistochemical staining enables molecular characterization of many benign and malignant lesions, which is critical for tailored treatment. The authors review commonly encountered benign and malignant breast diseases, their corresponding histopathologic phenotypes, and the histopathologic markers that are essential to clinching the diagnosis of these entities. As part of a multidisciplinary team that provides optimal patient care, radiologists should be knowledgeable of the foundations of histopathologic diagnosis and the implications for patient management to ensure appropriate radiologic-pathologic concordance. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.


Assuntos
Doenças Mamárias , Humanos , Doenças Mamárias/diagnóstico por imagem , Amarelo de Eosina-(YS) , Biópsia Guiada por Imagem , Agulhas , Fenótipo
13.
Nature ; 606(7915): 656-657, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35732755
14.
PLoS Genet ; 16(5): e1008767, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32357156

RESUMO

Despite the importance of dendritic targeting in neural circuit assembly, the mechanisms by which it is controlled still remain incompletely understood. We previously showed that in the developing Drosophila antennal lobe, the Wnt5 protein forms a gradient that directs the ~45˚ rotation of a cluster of projection neuron (PN) dendrites, including the adjacent DA1 and VA1d dendrites. We report here that the Van Gogh (Vang) transmembrane planar cell polarity (PCP) protein is required for the rotation of the DA1/VA1d dendritic pair. Cell type-specific rescue and mosaic analyses showed that Vang functions in the olfactory receptor neurons (ORNs), suggesting a codependence of ORN axonal and PN dendritic targeting. Loss of Vang suppressed the repulsion of the VA1d dendrites by Wnt5, indicating that Wnt5 signals through Vang to direct the rotation of the DA1 and VA1d glomeruli. We observed that the Derailed (Drl)/Ryk atypical receptor tyrosine kinase is also required for the rotation of the DA1/VA1d dendritic pair. Antibody staining showed that Drl/Ryk is much more highly expressed by the DA1 dendrites than the adjacent VA1d dendrites. Mosaic and epistatic analyses showed that Drl/Ryk specifically functions in the DA1 dendrites in which it antagonizes the Wnt5-Vang repulsion and mediates the migration of the DA1 glomerulus towards Wnt5. Thus, the nascent DA1 and VA1d glomeruli appear to exhibit Drl/Ryk-dependent biphasic responses to Wnt5. Our work shows that the final patterning of the fly olfactory map is the result of an interplay between ORN axons and PN dendrites, wherein converging pre- and postsynaptic processes contribute key Wnt5 signaling components, allowing Wnt5 to orient the rotation of nascent synapses through a PCP mechanism.


Assuntos
Antenas de Artrópodes/crescimento & desenvolvimento , Dendritos/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/crescimento & desenvolvimento , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Proteínas Wnt/metabolismo , Animais , Antenas de Artrópodes/metabolismo , Axônios/metabolismo , Padronização Corporal , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Membrana/genética , Neurônios Receptores Olfatórios/metabolismo , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Transdução de Sinais , Proteínas Wnt/genética
15.
J Strength Cond Res ; 37(5): 1117-1123, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36730045

RESUMO

ABSTRACT: Witt, CR, Grozier, CD, Killen, LG, Renfroe, LG, O'Neal, EK, and Waldman, HS. A self-selected 16:8 time-restricted eating protocol improves fat oxidation rates, markers of cardiometabolic health, and 10-km cycling performance in middle-age male cyclists. J Strength Cond Res 37(5): 1117-1123, 2023-The purpose of this study was to assess the impact of 4 weeks, 16:8 time restricted eating (TRE) on markers of metabolic health and 10-km time trial (TT) performance in middle-age male cyclists. Subjects ( n = 12; age, 40-60 years; V̇ o2 peak, 41.8 ± 5.6 ml·kg -1 ·min -1 ) consisting of individuals following a habitual Western diet completed a familiarization and 2 experimental trials [PRE] and [POST]. Following habitual Western diet without TRE, anthropometric measures were assessed, followed by completion of a graded exercise test and 10-km TT. Subjects then adhered to a 4-week TRE protocol where all calories had to be consumed within a self-selected 8-hour window and then returned for repeat testing. Although self-reported caloric intake did not statistically change PRE to POST, body mass (PRE, 83.2 ± 13.4 vs. POST, 80.7 ± 12.6 kg), fat mass (∼2.5 kg), and blood pressure (systolic, 8 mm Hg; diastolic, 4 mm Hg) were all significantly lower POST (all p < 0.05), with no changes in fat-free mass. Furthermore, fat oxidation significantly increased (PRE, 0.36 ± 0.03 vs. POST, 0.42 ± 0.03 g·min -1 ; p = 0.04) following the TRE intervention and 10-km TT performance improved by ∼2 minutes POST (PRE, 29.7 ± 7.3 vs. POST, 27.4 ± 5.5 minutes; p = 0.02). Overall, our data demonstrated that middle-age male cyclists adhering to a 4-week TRE protocol can improve their body composition profile and 10-km TT performance without detriments to fat-free mass.


Assuntos
Composição Corporal , Doenças Cardiovasculares , Pessoa de Meia-Idade , Humanos , Masculino , Adulto , Recém-Nascido , Oxirredução , Ingestão de Energia
16.
Ann Surg Oncol ; 29(1): 469-481, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34324114

RESUMO

INTRODUCTION: The Commission on Cancer/National Quality Forum breast radiotherapy quality measure establishes that for women < 70 years, adjuvant radiotherapy after breast conserving surgery (BCS) should be started < 1 year from diagnosis. This was intended to prevent accidental radiotherapy omission or delay due to a long interval between surgery and chemotherapy completion, when radiation is delivered. However, the impact on patients not receiving chemotherapy, who proceed from surgery directly to radiotherapy, remains unknown. PATIENTS AND METHODS: Patients aged 18-69, diagnosed with stage I-III breast cancer as their first and only cancer diagnosis (2004-2016), having BCS, for whom this measure would be applicable, were reviewed from the National Cancer Database. RESULTS: Among 308,521 patients, the median age was 57.0 years, and > 99% of all patients were compliant with the measure. The cohort of interest included 186,650 (60.5%) patients not receiving chemotherapy, with a mean age of 57.9 years. Of these, 90.5% received external beam radiotherapy (EBRT) and 9.5% brachytherapy. Among them, 24.9% started radiotherapy > 8 weeks after surgery. In a multivariable model, delay from surgery to radiotherapy increased the hazard ratios for overall survival to 9.0% (EBRT) per month and 3.0% (brachytherapy) per week. CONCLUSION: While 99.9% of patients undergoing BCS without chemotherapy remain compliant with the current quality measure, 25% have delays > 8 weeks to start radiation, which is associated with impaired survival. These data suggest that the current quality measure should be dichotomized into two, with or without chemotherapy, in order to impel prompt radiotherapy initiation and maximize outcomes in all patients.


Assuntos
Radioterapia (Especialidade) , Mama , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Indicadores de Qualidade em Assistência à Saúde , Radioterapia Adjuvante
17.
Drug Metab Dispos ; 50(7): 1027-1041, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35197313

RESUMO

Sulfotransferases are ubiquitous enzymes that transfer a sulfo group from the universal cofactor donor 3'-phosphoadenosine 5'-phosphosulfate to a broad range of acceptor substrates. In humans, the cytosolic sulfotransferases are involved in the sulfation of endogenous compounds such as steroids, neurotransmitters, hormones, and bile acids as well as xenobiotics including drugs, toxins, and environmental chemicals. The Golgi associated membrane-bound sulfotransferases are involved in post-translational modification of macromolecules from glycosaminoglycans to proteins. The sulfation of small molecules can have profound biologic effects on the functionality of the acceptor, including activation, deactivation, or enhanced metabolism and elimination. Sulfation of macromolecules has been shown to regulate a number of physiologic and pathophysiological pathways by enhancing binding affinity to regulatory proteins or binding partners. Over the last 25 years, crystal structures of these enzymes have provided a wealth of information on the mechanisms of this process and the specificity of these enzymes. This review will focus on the general commonalities of the sulfotransferases, from enzyme structure to catalytic mechanism as well as providing examples into how structural information is being used to either design drugs that inhibit sulfotransferases or to modify the enzymes to improve drug synthesis. SIGNIFICANCE STATEMENT: This manuscript honors Dr. Masahiko Negishi's contribution to the understanding of sulfotransferase mechanism, specificity, and roles in biology by analyzing the crystal structures that have been solved over the last 25 years.


Assuntos
Glicômica , Sulfotransferases , Humanos , Inativação Metabólica , Fosfoadenosina Fosfossulfato/metabolismo , Esteroides , Sulfotransferases/metabolismo
18.
Invest New Drugs ; 40(1): 81-90, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34417914

RESUMO

Background RX-3117 is an oral small molecule antimetabolite, cyclopentyl pyrimidyl nucleoside that is activated by cancer cells over-expressing uridine cytidine kinase 2 (UCK2). Single agent RX-3117 demonstrated efficacy in a phase I trial in patients with metastatic (met) pancreatic adenocarcinoma (PC). RX-3117 plus nab-paclitaxel (nab-Pac) was evaluated as a first line treatment in met-PC cancer. Methods This was a multicenter open label phase I/II 2-stage study investigating the combination of RX3117 plus nab-Pac in the frontline treatment of patients with met-PC. The phase I portion comprised a dose de-escalation design with primary objectives of determining the safety, tolerability and recommended phase 2 dose (RP2D) of RX-3117 (orally 700, 600, or 500 mg/day for 5 consecutive days with 2 days off/week) plus nab-Pac (intravenous (IV) 125 mg/m2 once weekly) for 3 weeks with 1 week off per a 4-week cycle. The primary objective was to determine the antitumor efficacy. Results 46 patients were enrolled (22 male/24 female; median age 67; 91% Caucasian). The RP2D of RX-3117 plus nab-Pac was 700 mg/day. No dose-limiting toxicities were observed (DLTs). The overall response rate (ORR) was 23.1% and disease control rate (DCR) 74.4%. RX-3117 pharmacokinetics (PK) results were similar to previously reported monotherapy phase 1 trial. All patients experienced a treatment emergent adverse event (TEAE) with the most common diarrhea, nausea, and fatigue.10.9% of patients experienced a serious adverse event (SAE) related to the combination. Conclusion RX-3117 plus nab-Pac in newly diagnosed met-PC patients demonstrated tolerability, safety, and early treatment efficacy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Albuminas/farmacocinética , Albuminas/uso terapêutico , Paclitaxel/farmacocinética , Paclitaxel/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Área Sob a Curva , Citidina/análogos & derivados , Citidina/farmacocinética , Citidina/farmacologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Meia-Vida , Humanos , Masculino , Dose Máxima Tolerável , Taxa de Depuração Metabólica , Pessoa de Meia-Idade
19.
J Phys Chem A ; 126(32): 5273-5282, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35921200

RESUMO

The photophysical characterization of two dyes used as scintillators, crystalline para-terphenyl and EJ-276, a plastic heavily doped with 2,5-diphenyloxazole (DPO), was investigated with steady-state absorption, time-resolved emission, and transient absorption at room and cryogenic temperatures. Application of time-gated emission spectroscopy allowed for the measurement of phosphorescence spectra and their temporal dynamics. The photophysical properties of plastic-embedded DPO are not substantially altered compared to those previously determined for this dye in solvents. Notably, the amount of delayed fluorescence is always greater than that of phosphorescence. However, our study of crystalline para-terphenyl suggests that a second phase called ß (perhaps comprising more planar molecules) functions as a triplet trap and decreases the amount of delayed fluorescence relative to phosphorescence. While the "main form" of para-terphenyl dominates absorption, the emissive properties (fluorescence, phosphorescence, and delayed fluorescence) are dominated by the ß-phase. Studies of the para-terphenyl crystal performed with femtosecond time-resolved transient absorption demonstrate that excitation from the main form of the para-terphenyl crystal is promptly transferred to the ß-phase with a time constant of roughly 300 ps. This work provides insight into the photophysical properties of two scintillators utilized to differentiate γ-ray- and neutron-induced signals.

20.
Breast Cancer Res Treat ; 189(2): 463-470, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34129117

RESUMO

PURPOSE: Controversy remains regarding the optimal margin width for patients with ductal carcinoma in situ (DCIS) who undergo breast conserving surgery (BCS). METHODS: Women with a primary DCIS diagnosis were enrolled in a statewide population-based cohort from 1997 to 2006. Patients were surveyed every two years with follow-up data available through 2016. Surgical pathology reports were collected for 559 participants following breast conserving surgery. Multivariable Cox proportional hazard models evaluated relationships between locoregional recurrence (LRR) and margin width in the presence or absence of adjuvant radiation therapy while controlling for age, menopausal status and duration of endocrine therapy use. RESULTS: The majority of women in this study were over 50yo (74%), 34% had high grade disease, and 77% underwent radiation. The overall LRR rate was 12%. A LRR occurred in 46 women who had radiation (11%) and 23 women who did not undergo radiation (19%). Univariate analysis identified smaller margin width, younger age, premenopausal status, no radiotherapy, and shorter endocrine therapy use associated with LRR. Multivariable models demonstrated that close margins (< 2 mm) were associated with an increased risk of recurrence when compared to margins ≥ 2 mm in width whether women received radiation (HR 1.98 CI 0.87-4.54) or not (HR 1.32 CI 0.27-6.49), but confidence intervals were wide. CONCLUSIONS: In this study, patients with DCIS and close margins were less likely to experience recurrence after routine re-excision to margins greater than 2 mm.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Intraductal não Infiltrante , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Intraductal não Infiltrante/epidemiologia , Carcinoma Intraductal não Infiltrante/radioterapia , Carcinoma Intraductal não Infiltrante/cirurgia , Feminino , Humanos , Margens de Excisão , Mastectomia Segmentar , Recidiva Local de Neoplasia/epidemiologia
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