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1.
Nature ; 570(7762): 480-483, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31243386

RESUMEN

Mechanical systems facilitate the development of a hybrid quantum technology comprising electrical, optical, atomic and acoustic degrees of freedom1, and entanglement is essential to realize quantum-enabled devices. Continuous-variable entangled fields-known as Einstein-Podolsky-Rosen (EPR) states-are spatially separated two-mode squeezed states that can be used for quantum teleportation and quantum communication2. In the optical domain, EPR states are typically generated using nondegenerate optical amplifiers3, and at microwave frequencies Josephson circuits can serve as a nonlinear medium4-6. An outstanding goal is to deterministically generate and distribute entangled states with a mechanical oscillator, which requires a carefully arranged balance between excitation, cooling and dissipation in an ultralow noise environment. Here we observe stationary emission of path-entangled microwave radiation from a parametrically driven 30-micrometre-long silicon nanostring oscillator, squeezing the joint field operators of two thermal modes by 3.40 decibels below the vacuum level. The motion of this micromechanical system correlates up to 50 photons per second per hertz, giving rise to a quantum discord that is robust with respect to microwave noise7. Such generalized quantum correlations of separable states are important for quantum-enhanced detection8 and provide direct evidence of the non-classical nature of the mechanical oscillator without directly measuring its state9. This noninvasive measurement scheme allows to infer information about otherwise inaccessible objects, with potential implications for sensing, open-system dynamics and fundamental tests of quantum gravity. In the future, similar on-chip devices could be used to entangle subsystems on very different energy scales, such as microwave and optical photons.

2.
Lancet ; 400(10359): 1195-1205, 2022 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-36216006

RESUMEN

BACKGROUND: Allopurinol is a urate-lowering therapy used to treat patients with gout. Previous studies have shown that allopurinol has positive effects on several cardiovascular parameters. The ALL-HEART study aimed to determine whether allopurinol therapy improves major cardiovascular outcomes in patients with ischaemic heart disease. METHODS: ALL-HEART was a multicentre, prospective, randomised, open-label, blinded-endpoint trial done in 18 regional centres in England and Scotland, with patients recruited from 424 primary care practices. Eligible patients were aged 60 years or older, with ischaemic heart disease but no history of gout. Participants were randomly assigned (1:1), using a central web-based randomisation system accessed via a web-based application or an interactive voice response system, to receive oral allopurinol up-titrated to a dose of 600 mg daily (300 mg daily in participants with moderate renal impairment at baseline) or to continue usual care. The primary outcome was the composite cardiovascular endpoint of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death. The hazard ratio (allopurinol vs usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis (excluding randomly assigned patients later found to have met one of the exclusion criteria). The safety analysis population included all patients in the modified intention-to-treat usual care group and those who took at least one dose of randomised medication in the allopurinol group. This study is registered with the EU Clinical Trials Register, EudraCT 2013-003559-39, and ISRCTN, ISRCTN32017426. FINDINGS: Between Feb 7, 2014, and Oct 2, 2017, 5937 participants were enrolled and then randomly assigned to receive allopurinol or usual care. After exclusion of 216 patients after randomisation, 5721 participants (mean age 72·0 years [SD 6·8], 4321 [75·5%] males, and 5676 [99·2%] white) were included in the modified intention-to-treat population, with 2853 in the allopurinol group and 2868 in the usual care group. Mean follow-up time in the study was 4·8 years (1·5). There was no evidence of a difference between the randomised treatment groups in the rates of the primary endpoint. 314 (11·0%) participants in the allopurinol group (2·47 events per 100 patient-years) and 325 (11·3%) in the usual care group (2·37 events per 100 patient-years) had a primary endpoint (hazard ratio [HR] 1·04 [95% CI 0·89-1·21], p=0·65). 288 (10·1%) participants in the allopurinol group and 303 (10·6%) participants in the usual care group died from any cause (HR 1·02 [95% CI 0·87-1·20], p=0·77). INTERPRETATION: In this large, randomised clinical trial in patients aged 60 years or older with ischaemic heart disease but no history of gout, there was no difference in the primary outcome of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death between participants randomised to allopurinol therapy and those randomised to usual care. FUNDING: UK National Institute for Health and Care Research.


Asunto(s)
Enfermedad de la Arteria Coronaria , Gota , Infarto del Miocardio , Isquemia Miocárdica , Accidente Cerebrovascular , Anciano , Alopurinol/uso terapéutico , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Femenino , Gota/tratamiento farmacológico , Humanos , Masculino , Infarto del Miocardio/tratamiento farmacológico , Isquemia Miocárdica/tratamiento farmacológico , Estudios Prospectivos , Accidente Cerebrovascular/tratamiento farmacológico , Resultado del Tratamiento , Reino Unido , Ácido Úrico
3.
Lancet ; 399(10319): 25-35, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34942103

RESUMEN

BACKGROUND: Reports suggest that COVID-19 vaccine effectiveness is decreasing, but whether this reflects waning or new SARS-CoV-2 variants-especially delta (B.1.617.2)-is unclear. We investigated the association between time since two doses of ChAdOx1 nCoV-19 vaccine and risk of severe COVID-19 outcomes in Scotland (where delta was dominant), with comparative analyses in Brazil (where delta was uncommon). METHODS: In this retrospective, population-based cohort study in Brazil and Scotland, we linked national databases from the EAVE II study in Scotland; and the COVID-19 Vaccination Campaign, Acute Respiratory Infection Suspected Cases, and Severe Acute Respiratory Infection/Illness datasets in Brazil) for vaccination, laboratory testing, clinical, and mortality data. We defined cohorts of adults (aged ≥18 years) who received two doses of ChAdOx1 nCoV-19 and compared rates of severe COVID-19 outcomes (ie, COVID-19 hospital admission or death) across fortnightly periods, relative to 2-3 weeks after the second dose. Entry to the Scotland cohort started from May 19, 2021, and entry to the Brazil cohort started from Jan 18, 2021. Follow-up in both cohorts was until Oct 25, 2021. Poisson regression was used to estimate rate ratios (RRs) and vaccine effectiveness, with 95% CIs. FINDINGS: 1 972 454 adults received two doses of ChAdOx1 nCoV-19 in Scotland and 42 558 839 in Brazil, with longer follow-up in Scotland because two-dose vaccination began earlier in Scotland than in Brazil. In Scotland, RRs for severe COVID-19 increased to 2·01 (95% CI 1·54-2·62) at 10-11 weeks, 3·01 (2·26-3·99) at 14-15 weeks, and 5·43 (4·00-7·38) at 18-19 weeks after the second dose. The pattern of results was similar in Brazil, with RRs of 2·29 (2·01-2·61) at 10-11 weeks, 3·10 (2·63-3·64) at 14-15 weeks, and 4·71 (3·83-5·78) at 18-19 weeks after the second dose. In Scotland, vaccine effectiveness decreased from 83·7% (95% CI 79·7-87·0) at 2-3 weeks, to 75·9% (72·9-78·6) at 14-15 weeks, and 63·7% (59·6-67·4) at 18-19 weeks after the second dose. In Brazil, vaccine effectiveness decreased from 86·4% (85·4-87·3) at 2-3 weeks, to 59·7% (54·6-64·2) at 14-15 weeks, and 42·2% (32·4-50·6) at 18-19 weeks. INTERPRETATION: We found waning vaccine protection of ChAdOx1 nCoV-19 against COVID-19 hospital admissions and deaths in both Scotland and Brazil, this becoming evident within three months of the second vaccine dose. Consideration needs to be given to providing booster vaccine doses for people who have received ChAdOx1 nCoV-19. FUNDING: UK Research and Innovation (Medical Research Council), Scottish Government, Research and Innovation Industrial Strategy Challenge Fund, Health Data Research UK, Fiocruz, Fazer o Bem Faz Bem Programme; Conselho Nacional de Desenvolvimento Científico e Tecnológico, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro. TRANSLATION: For the Portuguese translation of the abstract see Supplementary Materials section.


Asunto(s)
Vacunas contra la COVID-19/administración & dosificación , COVID-19/mortalidad , COVID-19/prevención & control , ChAdOx1 nCoV-19/administración & dosificación , Eficacia de las Vacunas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Femenino , Hospitalización , Humanos , Inmunización Secundaria , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , SARS-CoV-2/inmunología , Escocia/epidemiología , Factores de Tiempo , Vacunación
4.
J Chem Inf Model ; 63(11): 3288-3306, 2023 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-37208794

RESUMEN

While polymerization-induced self-assembly (PISA) has become a preferred synthetic route toward amphiphilic block copolymer self-assemblies, predicting their phase behavior from experimental design is extremely challenging, requiring time and work-intensive creation of empirical phase diagrams whenever self-assemblies of novel monomer pairs are sought for specific applications. To alleviate this burden, we develop here the first framework for a data-driven methodology for the probabilistic modeling of PISA morphologies based on a selection and suitable adaption of statistical machine learning methods. As the complexity of PISA precludes generating large volumes of training data with in silico simulations, we focus on interpretable low variance methods that can be interrogated for conformity with chemical intuition and that promise to work well with only 592 training data points which we curated from the PISA literature. We found that among the evaluated linear models, generalized additive models, and rule and tree ensembles, all but the linear models show a decent interpolation performance with around 0.2 estimated error rate and 1 bit expected cross entropy loss (surprisal) when predicting the mixture of morphologies formed from monomer pairs already encountered in the training data. When considering extrapolation to new monomer combinations, the model performance is weaker but the best model (random forest) still achieves highly nontrivial prediction performance (0.27 error rate, 1.6 bit surprisal), which renders it a good candidate to support the creation of empirical phase diagrams for new monomers and conditions. Indeed, we find in three case studies that, when used to actively learn phase diagrams, the model is able to select a smart set of experiments that lead to satisfactory phase diagrams after observing only relatively few data points (5-16) for the targeted conditions. The data set as well as all model training and evaluation codes are publicly available through the GitHub repository of the last author.


Asunto(s)
Aprendizaje Automático , Polimerizacion , Polímeros/química , Modelos Lineales
5.
Radiographics ; 43(2): e220078, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36525366

RESUMEN

Management of chronic thromboembolic pulmonary hypertension (CTEPH) should be determined by a multidisciplinary team, ideally at a specialized CTEPH referral center. Radiologists contribute to this multidisciplinary process by helping to confirm the diagnosis of CTEPH and delineating the extent of disease, both of which help determine a treatment decision. Preoperative assessment of CTEPH usually employs multiple imaging modalities, including ventilation-perfusion (V/Q) scanning, echocardiography, CT pulmonary angiography (CTPA), and right heart catheterization with pulmonary angiography. Accurate diagnosis or exclusion of CTEPH at imaging is imperative, as this remains the only form of pulmonary hypertension that is curative with surgery. Unfortunately, CTEPH is often misdiagnosed at CTPA, which can be due to technical factors, patient-related factors, radiologist-related factors, as well as a host of disease mimics including acute pulmonary embolism, in situ thrombus, vasculitis, pulmonary artery sarcoma, and fibrosing mediastinitis. Although V/Q scanning is thought to be substantially more sensitive for CTEPH compared with CTPA, this is likely due to lack of recognition of CTEPH findings rather than a modality limitation. Preoperative evaluation for pulmonary thromboendarterectomy (PTE) includes assessment of technical operability and surgical risk stratification. While the definitive therapy for CTEPH is PTE, other minimally invasive or noninvasive therapies also lead to clinical improvements including greater survival. Complications of PTE that can be identified at postoperative imaging include infection, reperfusion edema or injury, pulmonary hemorrhage, pericardial effusion or hemopericardium, and rethrombosis. ©RSNA, 2022 Online supplemental material is available for this article.


Asunto(s)
Hipertensión Pulmonar , Embolia Pulmonar , Humanos , Hipertensión Pulmonar/diagnóstico por imagen , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/cirugía , Embolia Pulmonar/complicaciones , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/cirugía , Endarterectomía/efectos adversos , Endarterectomía/métodos , Angiografía/métodos , Radiólogos , Enfermedad Crónica
6.
Int J Mol Sci ; 24(5)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36901734

RESUMEN

Targeting the botulinum neurotoxin light chain (LC) metalloprotease using small-molecule metal chelate inhibitors is a promising approach to counter the effects of the lethal toxin. However, to overcome the pitfalls associated with simple reversible metal chelate inhibitors, it is crucial to investigate alternative scaffolds/strategies. In conjunction with Atomwise Inc., in silico and in vitro screenings were conducted, yielding a number of leads, including a novel 9-hydroxy-4H-pyrido [1,2-a]pyrimidin-4-one (PPO) scaffold. From this structure, an additional series of 43 derivatives were synthesized and tested, resulting in a lead candidate with a Ki of 150 nM in a BoNT/A LC enzyme assay and 17 µM in a motor neuron cell-based assay. These data combined with structure-activity relationship (SAR) analysis and docking led to a bifunctional design strategy, which we termed "catch and anchor" for the covalent inhibition of BoNT/A LC. Kinetic evaluation was conducted on structures prepared from this catch and anchor campaign, providing kinact/Ki values, and rationale for inhibition seen. Covalent modification was validated through additional assays, including an FRET endpoint assay, mass spectrometry, and exhaustive enzyme dialysis. The data presented support the PPO scaffold as a novel candidate for targeted covalent inhibition of BoNT/A LC.


Asunto(s)
Clostridium botulinum , Péptido Hidrolasas , Diálisis Renal , Relación Estructura-Actividad , Metaloproteasas , Metales , Inhibidores de Proteasas/farmacología
7.
Mol Psychiatry ; 26(9): 5371-5388, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33526823

RESUMEN

Schizophrenia (Sz) is a highly polygenic disorder, with common, rare, and structural variants each contributing only a small fraction of overall disease risk. Thus, there is a need to identify downstream points of convergence that can be targeted with therapeutics. Reduction of microtubule-associated protein 2 (MAP2) immunoreactivity (MAP2-IR) is present in individuals with Sz, despite no change in MAP2 protein levels. MAP2 is phosphorylated downstream of multiple receptors and kinases identified as Sz risk genes, altering its immunoreactivity and function. Using an unbiased phosphoproteomics approach, we quantified 18 MAP2 phosphopeptides, 9 of which were significantly altered in Sz subjects. Network analysis grouped MAP2 phosphopeptides into three modules, each with a distinct relationship to dendritic spine loss, synaptic protein levels, and clinical function in Sz subjects. We then investigated the most hyperphosphorylated site in Sz, phosphoserine1782 (pS1782). Computational modeling predicted phosphorylation of S1782 reduces binding of MAP2 to microtubules, which was confirmed experimentally. We generated a transgenic mouse containing a phosphomimetic mutation at S1782 (S1782E) and found reductions in basilar dendritic length and complexity along with reduced spine density. Because only a limited number of MAP2 interacting proteins have been previously identified, we combined co-immunoprecipitation with mass spectrometry to characterize the MAP2 interactome in mouse brain. The MAP2 interactome was enriched for proteins involved in protein translation. These associations were shown to be functional as overexpression of wild type and phosphomimetic MAP2 reduced protein synthesis in vitro. Finally, we found that Sz subjects with low MAP2-IR had reductions in the levels of synaptic proteins relative to nonpsychiatric control (NPC) subjects and to Sz subjects with normal and MAP2-IR, and this same pattern was recapitulated in S1782E mice. These findings suggest a new conceptual framework for Sz-that a large proportion of individuals have a "MAP2opathy"-in which MAP function is altered by phosphorylation, leading to impairments of neuronal structure, synaptic protein synthesis, and function.


Asunto(s)
Esquizofrenia , Animales , Ratones , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Neuronas/metabolismo , Fosforilación , Esquizofrenia/genética , Esquizofrenia/metabolismo
8.
AIDS Care ; 34(5): 626-632, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-33856950

RESUMEN

Heterosexuals living with HIV report feeling additional HIV stigma compared to homosexual men, which may affect clinical outcomes. Yet, beyond routinely collected surveillance data, little is known about the characteristics of individuals who acquire HIV heterosexually and clinical outcomes by mode of sexual acquisition have not been directly compared. Using data from the Australian HIV Observational Database, we compared clinical characteristics of those with heterosexually-acquired (Het-HIV) to homosexually-acquired HIV (Hom-HIV) to investigate any differences and their implications for clinical management. 513 Het-HIV and 1467 Hom-HIV patients were included and contributed 3,127 and 9,457 person-years of follow-up, respectively. Compared with Hom-HIV, Het-HIV were more often born outside Australia (62.5% vs 39.9%, p<0.001), less likely to have Hepatitis C (4.8% vs 7.8%, p=0.029) and had lower median CD4 counts at diagnosis (292 vs 450 cells/µL, p<0.001) and cART initiation (270 vs 340 cells/µL, p<0.001). Despite these lower CD4 counts, there were no significant differences between groups for time to the major clinical endpoints of cART initiation, viral suppression, virological failure or all-cause mortality. Het-HIV had a lower risk of loss-to-follow-up than Hom-HIV (aHR 0.78; 95% CI 0.64-0.95). Further studies examining factors associated with, and interventions to inform retention in care are required.


Asunto(s)
Infecciones por VIH , Australia/epidemiología , Recuento de Linfocito CD4 , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Heterosexualidad , Homosexualidad , Humanos , Masculino
9.
Chem Soc Rev ; 50(3): 1587-1616, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33403373

RESUMEN

Biofilms are complex three-dimensional structures formed at interfaces by the vast majority of bacteria and fungi. These robust communities have an important detrimental impact on a wide range of industries and other facets of our daily lives, yet their removal is challenging owing to the high tolerance of biofilms towards conventional antimicrobial agents. This key issue has driven an urgent search for new innovative antibiofilm materials. Amongst these emerging approaches are highly promising materials that employ aqueous-soluble macromolecules, including peptides, proteins, synthetic polymers, and nanomaterials thereof, which exhibit a range of functionalities that can inhibit biofilm formation or detach and destroy organisms residing within established biofilms. In this Review, we outline the progress made in inhibiting and removing biofilms using macromolecular approaches, including a spotlight on cutting-edge materials that respond to environmental stimuli for "on-demand" antibiofilm activity, as well as synergistic multi-action antibiofilm materials. We also highlight materials that imitate and harness naturally derived species to achieve new and improved biomimetic and biohybrid antibiofilm materials. Finally, we share some speculative insights into possible future directions for this exciting and highly significant field of research.


Asunto(s)
Antiinfecciosos/farmacología , Biopelículas/efectos de los fármacos , Sustancias Macromoleculares/química , Antiinfecciosos/química , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Portadores de Fármacos/química , Sustancias Macromoleculares/farmacología , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/fisiología , Nanopartículas/química , Nanopartículas/toxicidad , Polímeros/química , Pseudomonas aeruginosa/fisiología
10.
J Biol Chem ; 295(49): 16529-16544, 2020 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-32934006

RESUMEN

The cystic fibrosis transmembrane conductance regulator (CFTR) is a plasma membrane anion channel that plays a key role in controlling transepithelial fluid movement. Excessive activation results in intestinal fluid loss during secretory diarrheas, whereas CFTR mutations underlie cystic fibrosis (CF). Anion permeability depends both on how well CFTR channels work (permeation/gating) and on how many are present at the membrane. Recently, treatments with two drug classes targeting CFTR-one boosting ion-channel function (potentiators) and the other increasing plasma membrane density (correctors)-have provided significant health benefits to CF patients. Here, we present an image-based fluorescence assay that can rapidly and simultaneously estimate both CFTR ion-channel function and the protein's proximity to the membrane. We monitor F508del-CFTR, the most common CF-causing variant, and confirm rescue by low temperature, CFTR-targeting drugs and second-site revertant mutation R1070W. In addition, we characterize a panel of 62 CF-causing mutations. Our measurements correlate well with published data (electrophysiology and biochemistry), further confirming validity of the assay. Finally, we profile effects of acute treatment with approved potentiator drug VX-770 on the rare-mutation panel. Mapping the potentiation profile on CFTR structures raises mechanistic hypotheses on drug action, suggesting that VX-770 might allow an open-channel conformation with an alternative arrangement of domain interfaces. The assay is a valuable tool for investigation of CFTR molecular mechanisms, allowing accurate inferences on gating/permeation. In addition, by providing a two-dimensional characterization of the CFTR protein, it could better inform development of single-drug and precision therapies addressing the root cause of CF disease.


Asunto(s)
Membrana Celular/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Activación del Canal Iónico , Microscopía Fluorescente , Aminofenoles/farmacología , Animales , Línea Celular , Membrana Celular/efectos de los fármacos , Regulador de Conductancia de Transmembrana de Fibrosis Quística/química , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Eliminación de Gen , Humanos , Procesamiento de Imagen Asistido por Computador , Activación del Canal Iónico/efectos de los fármacos , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Mutación Missense , Estructura Terciaria de Proteína , Quinolonas/farmacología , Ratas , Temperatura , Proteína Fluorescente Roja
11.
Ann Oncol ; 32(10): 1267-1275, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34293461

RESUMEN

BACKGROUND: In colon cancer, tumor deposits (TD) are considered in assigning prognosis and staging only in the absence of lymph node metastasis (i.e. stage III pN1c tumors). We aimed to evaluate the prognostic value of the presence and the number of TD in patients with stage III, node-positive colon cancer. PATIENTS AND METHODS: All participants from the CALGB/SWOG 80702 phase III trial were included in this post hoc analysis. Pathology reports were reviewed for the presence and the number of TD, lymphovascular and perineural invasion. Associations with disease-free survival (DFS) and overall survival (OS) were evaluated by multivariable Cox models adjusting for sex, treatment arm, T-stage, N-stage, lymphovascular invasion, perineural invasion and lymph node ratio. RESULTS: Overall, 2028 patients were included with 524 (26%) TD-positive and 1504 (74%) TD-negative tumors. Of the TD-positive patients, 80 (15.4%) were node negative (i.e. pN1c), 239 (46.1%) were pN1a/b (<4 positive lymph nodes) and 200 (38.5%) were pN2 (≥4 positive lymph nodes). The presence of TD was associated with poorer DFS [adjusted hazard ratio (aHR) = 1.63, 95% CI 1.33-1.98] and OS (aHR = 1.59, 95% CI 1.24-2.04). The negative effect of TD was observed for both pN1a/b and pN2 groups. Among TD-positive patients, the number of TD had a linear negative effect on DFS and OS. Combining TD and the number of lymph node metastases, 104 of 1470 (7.1%) pN1 patients were re-staged as pN2, with worse outcomes than patients confirmed as pN1 (3-year DFS rate: 65.4% versus 80.5%, P = 0.0003; 5-year OS rate: 87.9% versus 69.1%, P = <0.0001). DFS was not different between patients re-staged as pN2 and those initially staged as pN2 (3-year DFS rate: 65.4% versus 62.3%, P = 0.4895). CONCLUSION: Combining the number of TD and the number of lymph node metastases improved the prognostication accuracy of tumor-node-metastasis (TNM) staging.


Asunto(s)
Neoplasias del Colon , Extensión Extranodal , Neoplasias del Colon/patología , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos
12.
Cytokine ; 137: 155347, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33128925

RESUMEN

The purpose of this study was to compare the effects of exercise in cold-dry (CC, -20 °C, RH 40%) and normal conditions (NC, 20 °C, RH 60%) on salivary levels of pro-inflammatory and regulatory cytokines (IL-1RA, IL-8, and IL-5) and the airway response (FEV1 and FVC) in young healthy males. Participants (n = 11, age: 23.6 ± 3.1 years) completed an incremental to maximal exercise test and two exercise sessions in an environmental chamber in random order. Saliva samples were collected, and spirometry was performed prior to the maximal exercise test as well as pre and post-exercise for the CC and NC sessions. IL-8 levels increased from pre to post-exercise during NC but not during CC; the opposite trend was observed for IL-1RA. These data may provide insight into pathways associated with the development of airway hyperresponsiveness in healthy athletes.


Asunto(s)
Frío , Ejercicio Físico/fisiología , Humedad , Proteína Antagonista del Receptor de Interleucina 1/metabolismo , Interleucina-8/metabolismo , Saliva/metabolismo , Adulto , Estudios Cruzados , Prueba de Esfuerzo/métodos , Humanos , Masculino , Pruebas de Función Respiratoria/métodos , Espirometría/métodos , Adulto Joven
13.
Curr Opin Cardiol ; 36(6): 695-703, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34369401

RESUMEN

PURPOSE OF REVIEW: Discuss foundational concepts for artificial intelligence (AI) and review recent literature on its application to aortic disease. RECENT FINDINGS: Machine learning (ML) techniques are rapidly evolving for the evaluation of aortic disease - broadly categorized as algorithms for aortic segmentation, detection of pathology, and risk stratification. Advances in deep learning, particularly U-Net architectures, have revolutionized segmentation of the aorta and show potential for monitoring the size of aortic aneurysm and characterizing aortic dissection. These algorithms also facilitate application of more complex technologies including analysis of flow dynamics with 4D Flow magnetic resonance imaging (MRI) and computational simulation of fluid dynamics for aortic coarctation. In addition, AI algorithms have been proposed to assist in 'opportunistic' screening from routine imaging exams, including automated aortic calcification score, which has emerged as a strong predictor of cardiovascular risk. Finally, several ML algorithms are being explored for risk stratification of patients with aortic aneurysm and dissection, in addition to prediction of postprocedural complications. SUMMARY: Multiple ML techniques have potential for characterization and risk prediction of aortic aneurysm, dissection, coarctation, and atherosclerotic disease on computed tomography and MRI. This nascent field shows considerable promise with many applications in development and in early preclinical evaluation.


Asunto(s)
Enfermedades de la Aorta , Inteligencia Artificial , Algoritmos , Humanos , Aprendizaje Automático , Imagen por Resonancia Magnética
14.
Syst Biol ; 69(5): 813-819, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32259252

RESUMEN

The complex forces that shape butterfly wings have long been a subject of experimental and comparative research. Butterflies use their wings for flight, camouflage, mate recognition, warning, and mimicry. However, general patterns and correlations among wing shape and size evolution are still poorly understood. We collected geometric morphometric measurements from over 1400 digitized museum specimens of Papilio swallowtails and combined them with phylogenetic data to test two hypotheses: 1) forewing shape and size evolve independently of hindwing shape and size and 2) wing size evolves more quickly than wing shape. We also determined the major axes of wing shape variation and discovered that most shape variability occurs in hindwing tails and adjacent areas. We conclude that forewing shape and size are functionally and biomechanically constrained, whereas hindwings are more labile, perhaps in response to disruptive selective pressure for Batesian mimicry or against predation. The development of a significant, re-usable, digitized data resource will enable further investigation on tradeoffs between flight performance and ecological selective pressures, along with the degree to which intraspecific, local-scale selection may explain macroevolutionary patterns. [Batesian mimicry; Lepidoptera; geometric morphometrics; museum specimens.].


Asunto(s)
Mariposas Diurnas/anatomía & histología , Mariposas Diurnas/clasificación , Filogenia , Animales , Alas de Animales/anatomía & histología
15.
Bioorg Med Chem Lett ; 41: 128003, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33798703

RESUMEN

Small molecule drug discovery in the modern era necessitates rapid and simultaneous multiparameter optimization. Holistic drug design entails the strategic use of multiple drug design approaches for multiparameter optimization based on the goal and stage of the drug discovery program, the quantity and quality of data for analyses, and the availability and accuracy of predictive models. By leveraging orthogonal, complementary, or synergistic drug design approaches, holistic drug design may improve the efficiency of multiparameter optimization and increase the chance for success in small molecule drug discovery.


Asunto(s)
Descubrimiento de Drogas , Bibliotecas de Moléculas Pequeñas/síntesis química , Estructura Molecular , Bibliotecas de Moléculas Pequeñas/química
16.
Bioorg Med Chem Lett ; 49: 128293, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34332037

RESUMEN

PLD3 and PLD4 have recently been revealed to be endosomal exonucleases that regulate the innate immune response by digesting the ligands of nucleic acid sensors. These enzymes can suppress RNA and DNA innate immune sensors like toll-like receptor 9, and PLD4-deficent mice exhibit inflammatory disease. Targeting these immunoregulatory enzymes presents an opportunity to indirectly regulate innate immune nucleic acid sensors that could yield immunotherapies, adjuvants, and nucleic acid drug stabilizers. To aid in delineating the therapeutic potential of these targets, we have developed a high-throughput fluorescence enzymatic assay to identify modulators of PLD3 and PLD4. Screening of a diversity library (N = 17952) yielded preferential inhibitors of PLD3 and PLD4 in addition to a PLD3 selective activator. The modulation models of these compounds were delineated by kinetic analysis. This work presents an inexpensive and simple method to identify modulators of these immunoregulatory exonucleases.


Asunto(s)
Activadores de Enzimas/química , Inhibidores Enzimáticos/química , Exodesoxirribonucleasas/antagonistas & inhibidores , Fosfolipasa D/antagonistas & inhibidores , Pruebas de Enzimas , Colorantes Fluorescentes/química , Ensayos Analíticos de Alto Rendimiento , Humanos , Nitrofenoles/química , Nucleótidos de Timina/química , Umbeliferonas/química
17.
Bioorg Med Chem ; 42: 116246, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34130216

RESUMEN

We report the discovery of a fluorescent small molecule probe. This probe exhibits an emission increase in the presence of the oncoprotein MYC that can be attenuated by a competing inhibitor. Hydrogen-deuterium exchange mass spectrometry analysis, rationalized by induced-fit docking, suggests it binds to the "coiled-coil" region of the leucine zipper domain. Point mutations of this site produced functional MYC constructs resistant to inhibition in an oncogenic transformation assay by compounds that displace the probe. Utilizing this probe, we have developed a high-throughput assay to identify MYC inhibitor scaffolds. Screening of a diversity library (N = 1408, 384-well) and a library of pharmacologically active compounds (N = 1280, 1536-well) yielded molecules with greater drug-like properties than the probe. One lead is a potent inhibitor of oncogenic transformation and is specific for MYC relative to resistant mutants and transformation-inducing oncogenes. This method is simple, inexpensive, and does not require protein modification, DNA binding, or the dimer partner MAX. This assay presents an opportunity for MYC inhibition researchers to discover unique scaffolds.


Asunto(s)
Desarrollo de Medicamentos , Colorantes Fluorescentes/farmacología , Ensayos Analíticos de Alto Rendimiento , Proteínas Proto-Oncogénicas c-myc/antagonistas & inhibidores , Sitios de Unión/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Humanos , Estructura Molecular , Proteínas Proto-Oncogénicas c-myc/metabolismo , Relación Estructura-Actividad
18.
Nature ; 526(7573): 443-7, 2015 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-26322584

RESUMEN

Alzheimer disease (AD) is characterized by the accumulation of amyloid plaques, which are predominantly composed of amyloid-ß peptide. Two principal physiological pathways either prevent or promote amyloid-ß generation from its precursor, ß-amyloid precursor protein (APP), in a competitive manner. Although APP processing has been studied in great detail, unknown proteolytic events seem to hinder stoichiometric analyses of APP metabolism in vivo. Here we describe a new physiological APP processing pathway, which generates proteolytic fragments capable of inhibiting neuronal activity within the hippocampus. We identify higher molecular mass carboxy-terminal fragments (CTFs) of APP, termed CTF-η, in addition to the long-known CTF-α and CTF-ß fragments generated by the α- and ß-secretases ADAM10 (a disintegrin and metalloproteinase 10) and BACE1 (ß-site APP cleaving enzyme 1), respectively. CTF-η generation is mediated in part by membrane-bound matrix metalloproteinases such as MT5-MMP, referred to as η-secretase activity. η-Secretase cleavage occurs primarily at amino acids 504-505 of APP695, releasing a truncated ectodomain. After shedding of this ectodomain, CTF-η is further processed by ADAM10 and BACE1 to release long and short Aη peptides (termed Aη-α and Aη-ß). CTFs produced by η-secretase are enriched in dystrophic neurites in an AD mouse model and in human AD brains. Genetic and pharmacological inhibition of BACE1 activity results in robust accumulation of CTF-η and Aη-α. In mice treated with a potent BACE1 inhibitor, hippocampal long-term potentiation was reduced. Notably, when recombinant or synthetic Aη-α was applied on hippocampal slices ex vivo, long-term potentiation was lowered. Furthermore, in vivo single-cell two-photon calcium imaging showed that hippocampal neuronal activity was attenuated by Aη-α. These findings not only demonstrate a major functionally relevant APP processing pathway, but may also indicate potential translational relevance for therapeutic strategies targeting APP processing.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Hipocampo/citología , Metaloproteinasas de la Matriz Asociadas a la Membrana/metabolismo , Neuronas/fisiología , Proteolisis , Proteínas ADAM/metabolismo , Proteína ADAM10 , Enfermedad de Alzheimer/enzimología , Enfermedad de Alzheimer/metabolismo , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Secretasas de la Proteína Precursora del Amiloide/líquido cefalorraquídeo , Secretasas de la Proteína Precursora del Amiloide/deficiencia , Secretasas de la Proteína Precursora del Amiloide/genética , Precursor de Proteína beta-Amiloide/líquido cefalorraquídeo , Precursor de Proteína beta-Amiloide/química , Precursor de Proteína beta-Amiloide/genética , Animales , Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Ácido Aspártico Endopeptidasas/deficiencia , Ácido Aspártico Endopeptidasas/genética , Ácido Aspártico Endopeptidasas/metabolismo , Señalización del Calcio , Modelos Animales de Enfermedad , Femenino , Hipocampo/enzimología , Hipocampo/fisiología , Humanos , Técnicas In Vitro , Potenciación a Largo Plazo , Masculino , Metaloproteinasas de la Matriz Asociadas a la Membrana/deficiencia , Proteínas de la Membrana/metabolismo , Ratones , Peso Molecular , Neuritas/enzimología , Neuritas/metabolismo , Neuronas/enzimología , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Placa Amiloide , Procesamiento Proteico-Postraduccional , Análisis de la Célula Individual
19.
BMC Geriatr ; 21(1): 441, 2021 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-34311700

RESUMEN

BACKGROUND: Cognitive impairment (CI) is a risk factor for falls due to environmental or living settings, balance, gait and vision impairments, as well as medications. While previous systematic reviews have focused on the effectiveness of fall prevention programs in adults with cognitive impairment, very limited information is available on their implementation. This review examines what aspects of fall prevention interventions for community-dwelling adults with CI have been reported using the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework to support successful implementation. METHODS: We examined the included studies from our systematic review, which searched 7 databases for primary and secondary fall prevention interventions involving community-dwelling adults ≥50 years with mild to moderate CI. Reviewers screened citations and extracted data for study characteristics and the 5 dimensions (62 criteria) of the RE-AIM framework. RESULTS: Twelve randomized or clinical controlled trials (RCTs/CCTs) consisting of 8 exercise interventions, 3 multifactorial interventions, and 1 medication treatment were included in the review. Only 4 of 62 criteria were reported by all 12 included studies and 29 criteria were not reported by any of the studies. Five of the included studies reported on 20 or more of the 62 possible RE-AIM criteria and 3 of these studies self-identified as "feasibility" studies. While Reach was the best-reported construct by the included studies, followed by Effectiveness and Implementation, the criteria within the Adoption and Maintenance constructs were rarely mentioned by these studies. In general, there was also wide variation in how each of the criteria were reported on by study authors. CONCLUSION: Based on the reporting of RE-AIM components in this review, we are unable to make connections to successful intervention components and thus practice-based recommendations for fall prevention in those with CI. The lack of detail regarding implementation approaches greatly limits the interpretation and comparisons across studies to fully inform future research efforts.


Asunto(s)
Disfunción Cognitiva , Vida Independiente , Accidentes por Caídas/prevención & control , Disfunción Cognitiva/prevención & control , Humanos
20.
BMC Geriatr ; 21(1): 689, 2021 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-34893027

RESUMEN

BACKGROUND: Cognitive impairment (CI) increases an individual's risk of falls due to the role cognition plays in gait control. Older adults with dementia fall 2-3 times more than cognitively healthy older adults and 60-80% of people with dementia fall annually. Practitioners require evidence-based fall prevention best practices to reduce the risk of falls in cognitively impaired adults living in the community. METHODS: We conducted a systematic review and meta-analysis to identify the effectiveness of primary and secondary fall prevention interventions in reducing falls and fear of falling, and improving gait, balance, and functional mobility. We searched 7 databases for fall prevention interventions involving community-dwelling adults ≥50 years with mild to moderate CI. Reviewers screened citations, extracted data, and assessed risk of bias and certainty of evidence (GRADE). We assessed statistical and methodological heterogeneity and performed a meta-analysis of studies including subgroup analysis based on intervention and risk of bias groupings. RESULTS: Five hundred nine community-dwelling adults (mean age 67.5 to 84.0 years) with mild to moderate CI from 12 randomized or clinical controlled trials (RCTs/CCTs) were included in this review. Eight studies were exercise interventions, 3 were multifactorial, and 1 provided medication treatment. Fall prevention interventions had significant effects of medium magnitude on fear of falling (standardized mean difference (SMD) -0.73 [- 1.10, - 0.36]), balance (SMD 0.66 [0.19, 1.12]), and functional mobility measured as Timed Up and Go test (SMD -0.56 [- 0.94, - 0.17]) and significant effects of small magnitude on gait control (SMD 0.26 [0.08, 0.43]) all with moderate certainty of evidence. The meta-analysis showed no significant effects for falls (number of events or falls incidence). Sub-analysis showed that exercise and low risk of bias studies remained significant for balance and perceived risk of falls. CONCLUSION: The effect of fall prevention interventions on direct outcomes, such as falls, remains unclear in cognitively impaired individuals. Exercise interventions are effective at improving fall risk factors, however, high quality studies with longer follow-up and adequate sample sizes are needed to determine their effectiveness on falls directly. There remains a gap in terms of effective fall prevention interventions for older adults with CI.


Asunto(s)
Disfunción Cognitiva , Vida Independiente , Anciano , Anciano de 80 o más Años , Disfunción Cognitiva/prevención & control , Miedo , Humanos , Equilibrio Postural , Estudios de Tiempo y Movimiento
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