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1.
Nature ; 575(7784): 693-698, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31634899

RESUMO

Ferroptosis is an iron-dependent form of necrotic cell death marked by oxidative damage to phospholipids1,2. To date, ferroptosis has been thought to be controlled only by the phospholipid hydroperoxide-reducing enzyme glutathione peroxidase 4 (GPX4)3,4 and radical-trapping antioxidants5,6. However, elucidation of the factors that underlie the sensitivity of a given cell type to ferroptosis7 is crucial to understand the pathophysiological role of ferroptosis and how it may be exploited for the treatment of cancer. Although metabolic constraints8 and phospholipid composition9,10 contribute to ferroptosis sensitivity, no cell-autonomous mechanisms have been identified that account for the resistance of cells to ferroptosis. Here we used an expression cloning approach to identify genes in human cancer cells that are able to complement the loss of GPX4. We found that the flavoprotein apoptosis-inducing factor mitochondria-associated 2 (AIFM2) is a previously unrecognized anti-ferroptotic gene. AIFM2, which we renamed ferroptosis suppressor protein 1 (FSP1) and which was initially described as a pro-apoptotic gene11, confers protection against ferroptosis elicited by GPX4 deletion. We further demonstrate that the suppression of ferroptosis by FSP1 is mediated by ubiquinone (also known as coenzyme Q10, CoQ10): the reduced form, ubiquinol, traps lipid peroxyl radicals that mediate lipid peroxidation, whereas FSP1 catalyses the regeneration of CoQ10 using NAD(P)H. Pharmacological targeting of FSP1 strongly synergizes with GPX4 inhibitors to trigger ferroptosis in a number of cancer entities. In conclusion, the FSP1-CoQ10-NAD(P)H pathway exists as a stand-alone parallel system, which co-operates with GPX4 and glutathione to suppress phospholipid peroxidation and ferroptosis.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Ferroptose/genética , Glutationa/metabolismo , Proteínas Mitocondriais/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Humanos , Peroxidação de Lipídeos/genética , Camundongos , Proteínas Mitocondriais/genética , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo
2.
Clin Exp Immunol ; 216(3): 293-306, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38430552

RESUMO

Sepsis is characterized by a dysfunctional host response to infection culminating in life-threatening organ failure that requires complex patient management and rapid intervention. Timely diagnosis of the underlying cause of sepsis is crucial, and identifying those at risk of complications and death is imperative for triaging treatment and resource allocation. Here, we explored the potential of explainable machine learning models to predict mortality and causative pathogen in sepsis patients. By using a modelling pipeline employing multiple feature selection algorithms, we demonstrate the feasibility of identifying integrative patterns from clinical parameters, plasma biomarkers, and extensive phenotyping of blood immune cells. While no single variable had sufficient predictive power, models that combined five and more features showed a macro area under the curve (AUC) of 0.85 to predict 90-day mortality after sepsis diagnosis, and a macro AUC of 0.86 to discriminate between Gram-positive and Gram-negative bacterial infections. Parameters associated with the cellular immune response contributed the most to models predictive of 90-day mortality, most notably, the proportion of T cells among PBMCs, together with expression of CXCR3 by CD4+ T cells and CD25 by mucosal-associated invariant T (MAIT) cells. Frequencies of Vδ2+ γδ T cells had the most profound impact on the prediction of Gram-negative infections, alongside other T-cell-related variables and total neutrophil count. Overall, our findings highlight the added value of measuring the proportion and activation patterns of conventional and unconventional T cells in the blood of sepsis patients in combination with other immunological, biochemical, and clinical parameters.


Assuntos
Sepse , Humanos , Sepse/imunologia , Sepse/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Biomarcadores/sangue , Receptores CXCR3/metabolismo , Aprendizado de Máquina , Subunidade alfa de Receptor de Interleucina-2/sangue , Subunidade alfa de Receptor de Interleucina-2/imunologia , Imunidade Celular , Linfócitos T CD4-Positivos/imunologia , Linfócitos T/imunologia , Prognóstico , Infecções por Bactérias Gram-Negativas/imunologia
3.
J Rheumatol ; 51(4): 408-414, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302165

RESUMO

OBJECTIVE: To investigate the association of stair climbing difficulty and stair climbing frequency with the risk of all-cause mortality over 13 years in adults with or at high risk for knee OA. METHODS: We used data from the Osteoarthritis Initiative (OAI), a prospective cohort study of community-dwelling adults with or at high risk for symptomatic knee OA. The exposures were stair climbing difficulty and frequency, assessed at baseline using self-report questionnaires. The outcome was all-cause mortality, assessed from baseline through 13 years of follow-up. Kaplan-Meier survival curves and Cox proportional hazards regression were used to investigate the association between stair climbing exposures and all-cause mortality. RESULTS: Three hundred seven (6.81%) and 310 (6.84%) participants in the difficulty and frequency samples, respectively, died during 13 years of follow-up. Those who were limited in any capacity in terms of their stair climbing ability had 54% to 84% greater hazard of all-cause mortality, and those who climbed at least 7 flights of stairs per week had 38% lower hazard of all-cause mortality. CONCLUSION: Adults with or at high risk for knee OA who report difficulty with climbing stairs or who infrequently use stairs are at greater hazard of all-cause mortality. Stair climbing difficulty and frequency are simple to collect and changes may occur early in OA progression, allowing for early intervention. Brief questions about stair climbing behaviors can serve as a functional vital sign within the clinician's toolbox.


Assuntos
Osteoartrite do Joelho , Subida de Escada , Adulto , Humanos , Estudos Prospectivos , Articulação do Joelho , Extremidade Inferior
4.
Lung ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935158

RESUMO

PURPOSE: This study aimed to evaluate the hypothesis that active smoking impacts upon mediators and abundance of circulating fibrocyte cells in smoking-related disease characterised by fibrosis. METHODS: Flow cytometry and enzyme-linked immunosorbent assays were used to investigate blood from five patient groups: healthy never-smokers, healthy current smokers, stable chronic obstructive pulmonary disease (COPD) active smokers, idiopathic pulmonary fibrosis (IPF) never-smokers, and IPF active smokers. RESULTS: A significant inverse dose-response relationship was observed in healthy smokers among cumulative smoking burden (pack-years) and fibrocyte abundance (p = 0.006, r = -0.86). Among serum profibrotic fibrocyte chemokines measured, CCL18 rose significantly alongside fibrocyte numbers in all five subject groups, while having an inverse dose-response relationship with pack-year burden in healthy smokers (p = 0.003, r = -0.89). In IPF, CCL2 rose in direct proportion to fibrocyte abundance irrespective of smoking status but had lower serum levels in those currently smoking (p = < 0.001). For the study population, CXCL12 was decreased in pooled current smokers versus never-smokers (p = 0.03). CONCLUSION: The suppressive effect of current, as distinct from former, chronic smoking on circulating fibrocyte abundance in healthy smokers, and modulation of regulatory chemokine levels by active smoking may have implications for future studies of fibrocytes in smoking-related lung diseases as a potential confounding variable.

5.
J Peripher Nerv Syst ; 28(2): 179-190, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36995049

RESUMO

BACKGROUND AND AIMS: The expanding use of chemotherapy in curative cancer treatment has simultaneously resulted in a substantial and growing cohort of cancer survivors with prolonged disability from chemotherapy-induced peripheral neuropathy (CIPN). CIPN is associated with several commonly prescribed chemotherapeutics, including taxanes, platinum-based drugs, vinca alkaloids, bortezomib and thalidomide. These distinct classes of chemotherapeutics, with their varied neurotoxic mechanisms, often cause patients to suffer from a broad profile of neuropathic symptoms including chronic numbness, paraesthesia, loss of proprioception or vibration sensation and neuropathic pain. Decades of investigation by numerous research groups have provided substantial insights describing this disease. Despite these advances, there is currently no effective curative or preventative treatment option for CIPN and only the dual serotonin-norepinephrine reuptake inhibitor Duloxetine is recommended by clinical guidelines for the symptomatic treatment of painful CIPN. METHODS: In this review, we examine current preclinical models, with our analysis focused on translational relevance and value. RESULTS: Animal models have been pivotal in achieving a better understanding of the pathogenesis of CIPN. However, it has been challenging for researchers to develop appropriate preclinical models that are effective vehicles for the discovery of translatable treatment options. INTERPRETATION: Further development of preclinical models targeting translational relevance will promote value for preclinical outcomes in CIPN studies.


Assuntos
Antineoplásicos , Neoplasias , Neuralgia , Alcaloides de Vinca , Animais , Antineoplásicos/toxicidade , Neoplasias/tratamento farmacológico , Neuralgia/tratamento farmacológico , Modelos Animais de Doenças
6.
J Med Internet Res ; 25: e41358, 2023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-37200067

RESUMO

BACKGROUND: Recruiting study participants for clinical research is a challenging yet essential task. Social media platforms, such as Facebook, offer the opportunity to recruit participants through paid advertisements. These ad campaigns may be a cost-effective approach to reaching and recruiting participants who meet specific study criteria. However, little is known about the extent to which clicks on social media advertisements translate to the actual consent and enrollment of participants who meet the study criteria. Understanding this is especially important for clinical trials conducted remotely, such as telehealth-based studies, which open the possibility to recruit over large geographical areas and are becoming more common for the treatment of chronic health conditions, such as osteoarthritis (OA). OBJECTIVE: The aim of this study was to report on the conversion of clicks on a Facebook advertisement campaign to consent to enrollment in an ongoing telehealth physical therapy study for adults with knee OA, and the costs associated with recruitment. METHODS: This was a secondary analysis using data collected over the first 5 months of an ongoing study of adults with knee OA. The Delaware Physical Exercise and Activity for Knee Osteoarthritis program compares a virtually delivered exercise program to a control group receiving web-based resources among adults with knee OA. Advertisement campaigns were configured on Facebook to reach an audience who could be potentially eligible. Clicking on the advertisement directed potential participants to a web-based screening form to answer 6 brief questions related to the study criteria. Next, a research team member called individuals who met the criteria from the screening form and verbally asked additional questions related to the study criteria. Once considered eligible, an electronic informed consent form (ICF) was sent. We described the number of potential study participants who made it through each of these steps and then calculated the cost per participant who signed the ICF. RESULTS: In sum, between July and November 2021, a total of 33,319 unique users saw at least one advertisement, 9879 clicks were made, 423 web-based screening forms were completed, 132 participants were successfully contacted, 70 were considered eligible, and 32 signed the ICF. Recruitment costed an average of US $51.94 per participant. CONCLUSIONS: While there was a low conversion from clicks to actual consent, 32% (32/100) of the total sample required for the study were expeditiously consented over 5 months with a per-subject cost well below traditional means of recruitment, which ranges from US $90 to US $1000 per participant. TRIAL REGISTRATION: Clinicaltrails.gov NCT04980300; https://clinicaltrials.gov/ct2/show/NCT04980300.


Assuntos
Osteoartrite do Joelho , Mídias Sociais , Telemedicina , Adulto , Humanos , Publicidade , Seleção de Pacientes
7.
J Lipid Res ; 63(6): 100208, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35436499

RESUMO

The lipid envelope of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an essential component of the virus; however, its molecular composition is undetermined. Addressing this knowledge gap could support the design of antiviral agents as well as further our understanding of viral-host protein interactions, infectivity, pathogenicity, and innate immune system clearance. Lipidomics revealed that the virus envelope comprised mainly phospholipids (PLs), with some cholesterol and sphingolipids, and with cholesterol/phospholipid ratio similar to lysosomes. Unlike cellular membranes, procoagulant amino-PLs were present on the external side of the viral envelope at levels exceeding those on activated platelets. Accordingly, virions directly promoted blood coagulation. To investigate whether these differences could enable selective targeting of the viral envelope in vivo, we tested whether oral rinses containing lipid-disrupting chemicals could reduce infectivity. Products containing PL-disrupting surfactants (such as cetylpyridinium chloride) met European virucidal standards in vitro; however, components that altered the critical micelle concentration reduced efficacy, and products containing essential oils, povidone-iodine, or chlorhexidine were ineffective. This result was recapitulated in vivo, where a 30-s oral rinse with cetylpyridinium chloride mouthwash eliminated live virus in the oral cavity of patients with coronavirus disease 19 for at least 1 h, whereas povidone-iodine and saline mouthwashes were ineffective. We conclude that the SARS-CoV-2 lipid envelope i) is distinct from the host plasma membrane, which may enable design of selective antiviral approaches; ii) contains exposed phosphatidylethanolamine and phosphatidylserine, which may influence thrombosis, pathogenicity, and inflammation; and iii) can be selectively targeted in vivo by specific oral rinses.


Assuntos
COVID-19 , Antissépticos Bucais , Antivirais , Cetilpiridínio , Humanos , Lipídeos , Antissépticos Bucais/farmacologia , Povidona-Iodo , RNA Viral , SARS-CoV-2
8.
Lancet ; 398(10306): 1147-1156, 2021 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-34370972

RESUMO

BACKGROUND: A new syndrome of vaccine-induced immune thrombotic thrombocytopenia (VITT) has emerged as a rare side-effect of vaccination against COVID-19. Cerebral venous thrombosis is the most common manifestation of this syndrome but, to our knowledge, has not previously been described in detail. We aimed to document the features of post-vaccination cerebral venous thrombosis with and without VITT and to assess whether VITT is associated with poorer outcomes. METHODS: For this multicentre cohort study, clinicians were asked to submit all cases in which COVID-19 vaccination preceded the onset of cerebral venous thrombosis, regardless of the type of vaccine, interval between vaccine and onset of cerebral venous thrombosis symptoms, or blood test results. We collected clinical characteristics, laboratory results (including the results of tests for anti-platelet factor 4 antibodies where available), and radiological features at hospital admission of patients with cerebral venous thrombosis after vaccination against COVID-19, with no exclusion criteria. We defined cerebral venous thrombosis cases as VITT-associated if the lowest platelet count recorded during admission was below 150 × 109 per L and, if the D-dimer was measured, the highest value recorded was greater than 2000 µg/L. We compared the VITT and non-VITT groups for the proportion of patients who had died or were dependent on others to help them with their activities of daily living (modified Rankin score 3-6) at the end of hospital admission (the primary outcome of the study). The VITT group were also compared with a large cohort of patients with cerebral venous thrombosis described in the International Study on Cerebral Vein and Dural Sinus Thrombosis. FINDINGS: Between April 1 and May 20, 2021, we received data on 99 patients from collaborators in 43 hospitals across the UK. Four patients were excluded because they did not have definitive evidence of cerebral venous thrombosis on imaging. Of the remaining 95 patients, 70 had VITT and 25 did not. The median age of the VITT group (47 years, IQR 32-55) was lower than in the non-VITT group (57 years; 41-62; p=0·0045). Patients with VITT-associated cerebral venous thrombosis had more intracranial veins thrombosed (median three, IQR 2-4) than non-VITT patients (two, 2-3; p=0·041) and more frequently had extracranial thrombosis (31 [44%] of 70 patients) compared with non-VITT patients (one [4%] of 25 patients; p=0·0003). The primary outcome of death or dependency occurred more frequently in patients with VITT-associated cerebral venous thrombosis (33 [47%] of 70 patients) compared with the non-VITT control group (four [16%] of 25 patients; p=0·0061). This adverse outcome was less frequent in patients with VITT who received non-heparin anticoagulants (18 [36%] of 50 patients) compared with those who did not (15 [75%] of 20 patients; p=0·0031), and in those who received intravenous immunoglobulin (22 [40%] of 55 patients) compared with those who did not (11 [73%] of 15 patients; p=0·022). INTERPRETATION: Cerebral venous thrombosis is more severe in the context of VITT. Non-heparin anticoagulants and immunoglobulin treatment might improve outcomes of VITT-associated cerebral venous thrombosis. Since existing criteria excluded some patients with otherwise typical VITT-associated cerebral venous thrombosis, we propose new diagnostic criteria that are more appropriate. FUNDING: None.


Assuntos
Vacinas contra COVID-19/efeitos adversos , Trombose Intracraniana/epidemiologia , Púrpura Trombocitopênica Idiopática/epidemiologia , Vacinação/efeitos adversos , Adulto , Vacinas contra COVID-19/imunologia , Estudos de Coortes , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio , Humanos , Trombose Intracraniana/tratamento farmacológico , Trombose Intracraniana/mortalidade , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , SARS-CoV-2 , Reino Unido/epidemiologia , Trombose Venosa/tratamento farmacológico , Trombose Venosa/epidemiologia
9.
Ann Surg Oncol ; 29(3): 1839-1850, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34725764

RESUMO

BACKGROUND: Neoadjuvant therapy reduces fitness, muscle mass, and quality of life (QOL). For patients undergoing chemotherapy and surgery for esophagogastric cancer, maintenance of fitness is paramount. This study investigated the effect of exercise and psychological prehabilitation on anaerobic threshold (AT) at cardiopulmonary exercise testing (CPET). Secondary endpoints included peak oxygen uptake (peak VO2), skeletal muscle mass, QOL, and neoadjuvant therapy completion. METHODS: This parallel-arm randomized controlled trial assigned patients with locally advanced esophagogastric cancer to receive prehabilitation or usual care. The 15-week program comprised twice-weekly supervised exercises, thrice-weekly home exercises, and psychological coaching. CPET was performed at baseline, 2 weeks after neoadjuvant therapy, and 1 week preoperatively. Skeletal muscle cross-sectional area at L3 was analyzed on staging and restaging computed tomography. QOL questionnaires were completed at baseline, mid-neoadjuvant therapy, at restaging laparoscopy, and postoperatively at 2 weeks, 6 weeks and 6 months. RESULTS: Fifty-four participants were randomized (prehabilitation group, n = 26; control group, n = 28). No difference in AT between groups was observed post-neoadjuvant therapy. Prehabilitation resulted in an attenuated peak VO2 decline {-0.4 [95% confidence interval (CI) -0.8 to 0.1] vs. -2.5 [95% CI -2.8 to -2.2] mL/kg/min; p = 0.022}, less muscle loss [-11.6 (95% CI -14.2 to -9.0) vs. -15.6 (95% CI -18.7 to -15.4) cm2/m2; p = 0.049], and improved QOL. More prehabilitation patients completed neoadjuvant therapy at full dose [prehabilitation group, 18 (75%) vs. control group, 13 (46%); p = 0.036]. No adverse events were reported. CONCLUSIONS: This study has demonstrated some retention of cardiopulmonary fitness (peak VO2), muscle, and QOL in prehabilitation subjects. Further large-scale trials will help determine whether these promising findings translate into improved clinical and oncological outcomes. Trial Registration ClinicalTrials.gov NCT02950324.


Assuntos
Neoplasias Esofágicas , Neoplasias Gástricas , Neoplasias Esofágicas/terapia , Teste de Esforço , Terapia por Exercício , Humanos , Músculos , Terapia Neoadjuvante , Projetos Piloto , Cuidados Pré-Operatórios , Exercício Pré-Operatório , Qualidade de Vida , Neoplasias Gástricas/terapia
10.
Nat Mater ; 19(6): 630-636, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32451512

RESUMO

Van der Waals heterostructures offer attractive opportunities to design quantum materials. For instance, transition metal dichalcogenides (TMDs) possess three quantum degrees of freedom: spin, valley index and layer index. Furthermore, twisted TMD heterobilayers can form moiré patterns that modulate the electronic band structure according to the atomic registry, leading to spatial confinement of interlayer excitons (IXs). Here we report the observation of spin-layer locking of IXs trapped in moiré potentials formed in a heterostructure of bilayer 2H-MoSe2 and monolayer WSe2. The phenomenon of locked electron spin and layer index leads to two quantum-confined IX species with distinct spin-layer-valley configurations. Furthermore, we observe that the atomic registries of the moiré trapping sites in the three layers are intrinsically locked together due to the 2H-type stacking characteristic of bilayer TMDs. These results identify the layer index as a useful degree of freedom to engineer tunable few-level quantum systems in two-dimensional heterostructures.

11.
Opt Express ; 29(14): 22170-22191, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34265988

RESUMO

The design of photonic crystals with complete bandgaps has recently received considerable research focus for numerous reasons. This work leverages well-known nonlinear programming techniques to alleviate the non-smoothness caused by degenerate eigenvalues such that topology optimization problems can be solved with the open-source IPOPT software. A fully-vectorial plane wave expansion technique is used with an iterative eigensolver to efficiently predict dispersion properties of candidate structures. Nonlinear programming is employed to solve the inverse problem of designing three-dimensional periodic structures that exhibit complete two-dimensional (2D) and three-dimensional (3D) photonic bandgaps. Mesh refinement is performed to alleviate the large computational burden of designing and analyzing photonic crystals, and a periodic density filter is implemented to impose a minimum feature size for manufacturability considerations.

12.
Eur J Neurol ; 28(8): 2596-2602, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33969583

RESUMO

BACKGROUND: Patients' perceptions of outcome measures used in chronic inflammatory demyelinating polyneuropathy (CIDP) are unknown. METHODS: We performed a cross-sectional evaluation of patient perceptions of the Inflammatory Rasch-built Overall Disability Scale (I-RODS) from 41 subjects with CIDP through a structured questionnaire. We assessed perceived hesitation to provide a response, item importance and relevance, understanding of specific items and factors affecting responses. RESULTS: Hesitation to provide a categorical answer was reported by 20% of subjects or more, for 5/24 (20.8%) items. Uncertainty was most frequent for "travel by public transport" (22.4%) and "catch an object (e.g., ball)" (24%). Six of 24 (25%) items were perceived as unimportant to their disease by at least a third of participants. Items most commonly perceived as unimportant were "travel by public transport" in 53.7%, "catch an object (e.g., ball)" in 61% and "dance" in 65.9%. Several items were frequently perceived as irrelevant. These included "move a chair" (39%), "do the dishes" (46.3%), "catch an object (e.g., ball)" (61%), "travel by public transport" (68.3%) and "stand for hours" (82.9%). The understanding of multiple items such as "read a book", "sit on a toilet" and "take a shower" was found to be highly variable. Fatigue was perceived more commonly than mood (53.7% vs. 17.1%, p = 0.001), and more commonly in younger subjects (p = 0.037), as influencing responses to the I-RODS. CONCLUSIONS: Patient-perceived uncertainty, unimportance, irrelevance and poor understanding of items, as well as fatigue and mood, impact on the value of the I-RODS. Greater emphasis on individualized disability assessments requires consideration in future.


Assuntos
Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Estudos Transversais , Humanos , Avaliação de Resultados em Cuidados de Saúde , Percepção , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico , Índice de Gravidade de Doença
13.
Int J Behav Nutr Phys Act ; 18(1): 74, 2021 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-34090471

RESUMO

BACKGROUND: Moderate-to-vigorous intensity physical activity (MVPA) is associated with favorable self-rated mental and physical health. Conversely, poor self-rated health in these domains could precede unfavorable shifts in activity. We evaluated bidirectional associations of accelerometer-estimated time spent in stationary behavior (SB), light intensity physical activity (LPA), and MVPA with self-rated health over 10 years in in the CARDIA longitudinal cohort study. METHODS: Participants (n = 894, age: 45.1 ± 3.5; 63% female; 38% black) with valid accelerometry wear and self-rated health at baseline (2005-6) and 10-year follow-up (2015-6) were included. Accelerometry data were harmonized between exams and measured mean total activity and duration (min/day) in SB, LPA, and MVPA; duration (min/day) in long-bout and short-bout SB (≥30 min vs. < 30 min) and MVPA (≥10 min vs. < 10 min) were also quantified. The Short-Form 12 Questionnaire measured both a mental component score (MCS) and physical component score (PCS) of self-rated health (points). Multivariable linear regression associated baseline accelerometry variables with 10-year changes in MCS and PCS. Similar models associated baseline MCS and PCS with 10-year changes in accelerometry measures. RESULTS: Over 10-years, average (SD) MCS increased 1.05 (9.07) points, PCS decreased by 1.54 (7.30) points, and activity shifted toward greater SB and less mean total activity, LPA, and MVPA (all p < 0.001). Only baseline short-bout MVPA was associated with greater 10-year increases in MCS (+ 0.92 points, p = 0.021), while baseline mean total activity, MVPA, and long-bout MVPA were associated with greater 10-year changes in PCS (+ 0.53 to + 1.47 points, all p < 0.005). In the reverse direction, higher baseline MCS and PCS were associated with favorable 10-year changes in mean total activity (+ 9.75 cpm, p = 0.040, and + 15.66 cpm, p < 0.001, respectively) and other accelerometry measures; for example, higher baseline MCS was associated with - 13.57 min/day of long-bout SB (p < 0.001) and higher baseline PCS was associated with + 2.83 min/day of MVPA (p < 0.001) in fully adjusted models. CONCLUSIONS: The presence of bidirectional associations between SB and activity with self-rated health suggests that individuals with low overall activity levels and poor self-rated health are at high risk for further declines and supports intervention programming that aims to dually increase activity levels and improve self-rated health.


Assuntos
Acelerometria/estatística & dados numéricos , Exercício Físico/fisiologia , Comportamento Sedentário , Autorrelato/estatística & dados numéricos , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
14.
Arch Phys Med Rehabil ; 102(10): 1888-1894, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34175271

RESUMO

OBJECTIVE: To examine the association of the volume and intensity of daily walking at baseline with the risk of knee replacement (KR) over 5 years in adults with advanced structural knee osteoarthritis. DESIGN: Prospective, longitudinal, and multicenter observational study. SETTING: Osteoarthritis Initiative study with follow-up from 2008-2015. PARTICIPANTS: Community-dwelling adults with or at risk of knee osteoarthritis were recruited from 4 sites in the United States (N=516; mean age, 67.7±8.6y; body mass index, 29.3±4.7 kg/m2; 52% female). We included participants with advanced structural disease, without KR and had valid daily walking data (quantified using Actigraph GT1M), at baseline. INTERVENTIONS: Not applicable. MAIN OUTCOMES: KR. Walking volume was measured as steps/day and intensity as minutes/day spent not walking (0 steps/min) and walking at very light (1-49 steps/min), light (50-100 steps/min), or moderate (>100 steps/min) intensities. To examine the relationship of walking volume and intensity with the risk of KR, we calculated hazard ratios (HRs) and 95% confidence intervals (CIs) adjusting for covariates. RESULTS: Of 516 adults with advanced structural disease, 88 received a KR over 5 years (17%). Walking an additional 1000 steps/d was not associated with the risk of KR (adjusted HR=0.95; 95% CI, 0.84-1.04). Statistically, replacing 10 min/d of very light and light walking with 10 min/d of moderate walking reduced the risk of KR incidence by 35% and 37%, respectively (adjusted HR=0.65, 95% CI, 0.45-0.94, for very light and adjusted HR=0.63; 95% CI, 0.40-1.00, for light). CONCLUSIONS: Daily walking volume and intensity did not increase KR risk over 5 years and may be protective in some cases in adults with advanced structural knee osteoarthritis.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho/reabilitação , Osteoartrite do Joelho/cirurgia , Caminhada/estatística & dados numéricos , Acelerometria , Idoso , Estudos de Coortes , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Estados Unidos
15.
J Neurophysiol ; 124(1): 232-244, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32519566

RESUMO

Oxaliplatin chemotherapy produces acute changes in peripheral nerve excitability in humans by modulating voltage-gated Na+ channel activity. However, there are few animal studies of oxaliplatin-induced neuropathy that demonstrate similar changes in excitability. In the present study, we measured the excitability of motor and sensory caudal nerve in C57BL/6 mice after oxaliplatin injections either systemically (intraperitoneal) or locally (intramuscular at the base of the tail). As opposed to intraperitoneal administration of oxaliplatin, a single intramuscular injection of oxaliplatin produced changes in both motor and sensory axons. In motor axons, oxaliplatin caused a greater change in response to long-lasting depolarization and an upward shift in the recovery cycle, particularly at 24 h [depolarizing threshold electrotonus (TEd) 10-20 ms, P = 0.0095; TEd 90-100 ms, P = 0.0056) and 48 h (TEd 10-20 ms, P = 0.02; TEd 90-100 ms, P = 0.04) posttreatment. Oxaliplatin treatment also stimulated the production of afterdischarges in motor axons. These changes were transient and showed dose dependence. Mathematical modeling demonstrated that these changes could be accounted for by slowing inactivation of voltage-gated Na+ channels by 73.3% and reducing fast K+ conductance by 47% in motor axons. In sensory axons, oxaliplatin caused an increase in threshold, a reduction in peak amplitude, and greater threshold changes to strong hyperpolarizing currents on days 4 and 8. Thus, local administration of oxaliplatin produced clinically relevant changes in nerve excitability in mice and may provide an alternative approach for the study of acute oxaliplatin-induced neurotoxicity.NEW & NOTEWORTHY We present a novel mouse model of acute oxaliplatin-induced peripheral neurotoxicity that is comparable to clinical observations. Intramuscular injection of oxaliplatin produced acute changes in motor nerve excitability that were attributable to alterations in Na+ and K+ channel activity. Conversely, we were unable to show any significant changes in nerve excitability with systemic intraperitoneal injections of oxaliplatin. This study suggests that local intramuscular injection is a valid approach for modelling oxaliplatin-induced peripheral neuropathy in animals.


Assuntos
Antineoplásicos/efeitos adversos , Axônios/efeitos dos fármacos , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Neurônios Motores/efeitos dos fármacos , Síndromes Neurotóxicas/fisiopatologia , Oxaliplatina/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/fisiopatologia , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Antineoplásicos/administração & dosagem , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Teóricos , Oxaliplatina/administração & dosagem , Pesquisa Translacional Biomédica
16.
MMWR Morb Mortal Wkly Rep ; 69(21): 647-650, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32463810

RESUMO

An estimated 257 million persons worldwide have chronic hepatitis B virus (HBV) infection (1). CDC recommends HBV testing for persons from countries with intermediate to high HBV prevalence (≥2%), including newly arriving refugees (2). Complications of chronic HBV infection include liver cirrhosis and hepatocellular carcinoma, which develop in 15%-25% of untreated adults infected in infancy or childhood (3). HBV-infected patients require regular monitoring for both infection and sequelae. Several studies have evaluated initial linkage to HBV care for both refugee and nonrefugee immigrant populations (4-9), but none contained standardized definitions for either linkage to or long-term retention in care for chronic HBV-infected refugees. To assess chronic HBV care, three urban sites that perform refugee domestic medical examinations and provide primary care collaborated in a quality improvement evaluation. Sites performed chart reviews and prospective outreach to refugees with positive test results for presumed HBV infection during domestic medical examinations. Linkage to care (29%-53%), retention in care (11%-21%), and outreach efforts (22%-71% could not be located) demonstrated poor access to initial and ongoing HBV care. Retrospective outreach was low-yield. Interventions that focus on prospective outreach and addressing issues related to access to care might improve linkage to and retention in care.


Assuntos
Continuidade da Assistência ao Paciente/estatística & dados numéricos , Hepatite B/diagnóstico , Hepatite B/terapia , Refugiados/estatística & dados numéricos , Retenção nos Cuidados/estatística & dados numéricos , Adulto , Cidades , Feminino , Vírus da Hepatite B/isolamento & purificação , Humanos , Laboratórios , Masculino , Programas de Rastreamento , Avaliação de Programas e Projetos de Saúde , Estados Unidos , Adulto Jovem
17.
BMC Geriatr ; 20(1): 394, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028223

RESUMO

BACKGROUND: Frail older surgical patients face more than a two-fold increase in postoperative complications, including myocardial infarction, deep vein thrombosis, pulmonary embolism, pneumonia, ileus, and others. Many of these complications occur because of postoperative loss of stamina and poor mobility. Preoperative exercise may better prepare these vulnerable patients for surgery. We present the protocol for our ongoing randomized trial to assess the impact of a preoperative walking intervention with remote coaching and pedometer on outcomes of stamina (six-minute walk distance- 6MWD) and mobility (postoperative steps) in older adults with frailty traits. METHODS: We will be conducting a randomized clinical trial with a total of 120 patients permitting up to a 33% rate of attrition, to reach a final sample size of 80 (with 40 patients for each study arm). We will include patients who are age 60 or higher, score 4 or greater on the Edmonton Frailty Scale assessment, and will be undergoing a surgical operation that requires a 2 or more night hospital stay to be eligible for our trial. Using block randomization stratified on baseline 6MWD, we will assign patients to wear a pedometer. At the end of three baseline days, an athletic trainer (AT) will provide a daily step count goal reflecting a 10-20% increase from baseline. Subsequently, the AT will call weekly to further titrate the goal or calls more frequently if the patient is not meeting the prescribed goal. Controls will receive general walking advice. Our main outcome is change in 6MWD on postoperative day (POD) 2/3 vs. baseline. We will also collect 6MWD approximately 4 weeks after surgery and daily in-hospital steps. CONCLUSION: If changes in a 6MWD and step counts are significantly higher for the intervention group, we believe this will confirm our hypothesis that the intervention leads to decreased loss of stamina and mobility. Once confirmed, we anticipate expanding to multiple centers to assess the interventional impact on clinical endpoints. TRIAL REGISTRATION: The randomized clinical trial was registered on clinicaltrials.gov under the identifier NCT03892187 on March 27, 2019.


Assuntos
Protocolos Clínicos , Fragilidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Procedimentos Cirúrgicos Operatórios , Idoso , Humanos , Cuidados Pré-Operatórios , Período Pré-Operatório , Resultado do Tratamento , Caminhada
18.
Nucleic Acids Res ; 46(15): 7662-7674, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-29939287

RESUMO

The transcriptional regulator EVI1 has an essential role in early hematopoiesis and development. However, aberrantly high expression of EVI1 has potent oncogenic properties and confers poor prognosis and chemo-resistance in leukemia and solid tumors. To investigate to what extent EVI1 function might be regulated by post-translational modifications we carried out mass spectrometry- and antibody-based analyses and uncovered an ATM-mediated double phosphorylation of EVI1 at the carboxy-terminal S858/S860 SQS motif. In the presence of genotoxic stress EVI1-WT (SQS), but not site mutated EVI1-AQA was able to maintain transcriptional patterns and transformation potency, while under standard conditions carboxy-terminal mutation had no effect. Maintenance of hematopoietic progenitor cell clonogenic potential was profoundly impaired with EVI1-AQA compared with EVI1-WT, in particular in the presence of genotoxic stress. Exploring mechanistic events underlying these observations, we showed that after genotoxic stress EVI1-WT, but not EVI1-AQA increased its level of association with its functionally essential interaction partner CtBP1, implying a role for ATM in regulating EVI1 protein interactions via phosphorylation. This aspect of EVI1 regulation is therapeutically relevant, as chemotherapy-induced genotoxicity might detrimentally sustain EVI1 function via stress response mediated phosphorylation, and ATM-inhibition might be of specific targeted benefit in EVI1-overexpressing malignancies.


Assuntos
Oxirredutases do Álcool/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Autorrenovação Celular/genética , Proteínas de Ligação a DNA/genética , Regulação Leucêmica da Expressão Gênica , Proteína do Locus do Complexo MDS1 e EVI1/genética , Doença Aguda , Oxirredutases do Álcool/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Proteína do Locus do Complexo MDS1 e EVI1/química , Proteína do Locus do Complexo MDS1 e EVI1/metabolismo , Mutação , Fosforilação
19.
BMC Musculoskelet Disord ; 21(1): 783, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33246446

RESUMO

BACKGROUND: The purpose of this prospective case series study was to compare changes in early postoperative physical activity and physical function between 6 weeks and 3 and 6 months after lumbar spine surgery. METHODS: Fifty-three patients (mean [95% confidence interval; CI] age = 59.2 [56.2, 62.3] years, 64% female) who underwent spine surgery for a degenerative lumbar condition were assessed at 6 weeks and 3- and 6-months after surgery. The outcomes were objectively-measured physical activity (accelerometry) and patient-reported and objective physical function. Physical activity was assessed using mean steps/day and time spent in moderate to vigorous physical activity (MVPA) over a week. Physical function measures included Oswestry Disability Index (ODI), 12-item Short Form Health Survey (SF-12), Timed Up and Go (TUG), and 10-Meter Walk (10 MW). We compared changes over time in physical activity and function using generalized estimating equations with robust estimator and first-order autoregressive covariance structure. Proportion of patients who engaged in meaningful physical activity (e.g., walked at least 4400 and 6000 steps/day or engaged in at least 150 min/week in MVPA) and achieved clinically meaningful changes in physical function were compared at 3 and 6 months. RESULTS: After surgery, 72% of patients initiated physical therapy (mean [95%CI] sessions =8.5 [6.6, 10.4]) between 6 weeks and 3 months. Compared to 6 weeks post-surgery, no change in steps/day or time in MVPA/week was observed at 3 or 6 months. From 21 to 23% and 9 to 11% of participants walked at least 4400 and 6000 steps/day at 3 and 6 months, respectively, while none of the participants spent at least 150 min/week in MVPA at these same time points. Significant improvements were observed on ODI, SF-12, TUG and 10 MW (p <  0.05), with over 43 to 68% and 62 to 87% achieving clinically meaningful improvements on these measures at 3 and 6 months, respectively. CONCLUSION: Limited improvement was observed in objectively-measured physical activity from 6 weeks to 6 months after spine surgery, despite moderate to large function gains. Early postoperative physical therapy interventions targeting physical activity may be needed.


Assuntos
Exercício Físico , Vértebras Lombares , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Resultado do Tratamento
20.
J Med Internet Res ; 22(10): e21632, 2020 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-33027035

RESUMO

BACKGROUND: Physical distancing measures taken to contain COVID-19 transmission may substantially reduce physical activity levels and cause individuals to adopt a more sedentary lifestyle. OBJECTIVE: The objective of this study is to determine if there was any change in daily steps, an important component of daily physical activity, and examine risk factors for frequent low daily steps during the COVID-19 epidemic. METHODS: We used data collected from the Step Study, a population-based longitudinal study of walking activity among residents aged ≥40 years in Changsha, China. Daily steps were collected via a smartphone linked to WeChat, a social networking platform. We plotted mean daily steps and the prevalence of low daily steps (≤1500 steps/day) 30 days before (reference period) and 30 days after (epidemic period) January 21, 2020 (date of the first COVID-19 case diagnosed in Changsha), and compared it with the same corresponding period from 2019. We examined the association of risk factors with the prevalence of frequent low daily steps (≤1500 steps/day for ≥14 days) using logistic regression. RESULTS: Among 3544 participants (mean age 51.6 years; n=1226 females, 34.6%), mean daily steps dropped from 8097 to 5440 and the prevalence of low daily steps increased from 3% (2287/76,136 person-day) to 18.5% (12,951/70,183 person-day) during the reference and epidemic periods, respectively. No such phenomenon was observed during the corresponding period in 2019. Older age (P for interaction=.001) and female sex (P for interaction<.001) were both associated with a higher prevalence of frequent low daily steps and were more pronounced during the epidemic period. More education was associated with a lower prevalence of frequent low daily steps during the reference period but not the epidemic period (P for interaction=.34). Body mass index or comorbidity were not associated with frequent low daily steps during either period. CONCLUSIONS: Daily steps of Changsha residents aged ≥40 years dropped significantly during the COVID-19 period, especially among older adults and females. Although successful physical distancing, measured by the rapid downward trend in daily step counts of residents, played a critical role in the containment of the COVID-19 epidemic, our findings of an increase in the prevalence of frequent low daily steps raise concerns about unintended effects on physical activity.


Assuntos
Infecções por Coronavirus/epidemiologia , Exercício Físico , Pneumonia Viral/epidemiologia , Isolamento Social , Caminhada , Idoso , COVID-19 , China/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pandemias , Comportamento Sedentário
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