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1.
Cell ; 173(7): 1581-1592, 2018 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-29887378

RESUMEN

Machine learning, a collection of data-analytical techniques aimed at building predictive models from multi-dimensional datasets, is becoming integral to modern biological research. By enabling one to generate models that learn from large datasets and make predictions on likely outcomes, machine learning can be used to study complex cellular systems such as biological networks. Here, we provide a primer on machine learning for life scientists, including an introduction to deep learning. We discuss opportunities and challenges at the intersection of machine learning and network biology, which could impact disease biology, drug discovery, microbiome research, and synthetic biology.


Asunto(s)
Biología Computacional/métodos , Aprendizaje Automático , Algoritmos , Bases de Datos Factuales , Descubrimiento de Drogas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Microbiota , Redes Neurales de la Computación
2.
Proc Natl Acad Sci U S A ; 121(24): e2318124121, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38830100

RESUMEN

There is much excitement about the opportunity to harness the power of large language models (LLMs) when building problem-solving assistants. However, the standard methodology of evaluating LLMs relies on static pairs of inputs and outputs; this is insufficient for making an informed decision about which LLMs are best to use in an interactive setting, and how that varies by setting. Static assessment therefore limits how we understand language model capabilities. We introduce CheckMate, an adaptable prototype platform for humans to interact with and evaluate LLMs. We conduct a study with CheckMate to evaluate three language models (InstructGPT, ChatGPT, and GPT-4) as assistants in proving undergraduate-level mathematics, with a mixed cohort of participants from undergraduate students to professors of mathematics. We release the resulting interaction and rating dataset, MathConverse. By analyzing MathConverse, we derive a taxonomy of human query behaviors and uncover that despite a generally positive correlation, there are notable instances of divergence between correctness and perceived helpfulness in LLM generations, among other findings. Further, we garner a more granular understanding of GPT-4 mathematical problem-solving through a series of case studies, contributed by experienced mathematicians. We conclude with actionable takeaways for ML practitioners and mathematicians: models that communicate uncertainty, respond well to user corrections, and can provide a concise rationale for their recommendations, may constitute better assistants. Humans should inspect LLM output carefully given their current shortcomings and potential for surprising fallibility.


Asunto(s)
Lenguaje , Matemática , Solución de Problemas , Humanos , Solución de Problemas/fisiología , Estudiantes/psicología
3.
N Engl J Med ; 388(25): 2315-2325, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37224232

RESUMEN

BACKGROUND: Electroconvulsive therapy (ECT) and subanesthetic intravenous ketamine are both currently used for treatment-resistant major depression, but the comparative effectiveness of the two treatments remains uncertain. METHODS: We conducted an open-label, randomized, noninferiority trial involving patients referred to ECT clinics for treatment-resistant major depression. Patients with treatment-resistant major depression without psychosis were recruited and assigned in a 1:1 ratio to receive ketamine or ECT. During an initial 3-week treatment phase, patients received either ECT three times per week or ketamine (0.5 mg per kilogram of body weight over 40 minutes) twice per week. The primary outcome was a response to treatment (i.e., a decrease of ≥50% from baseline in the score on the 16-item Quick Inventory of Depressive Symptomatology-Self-Report; scores range from 0 to 27, with higher scores indicating greater depression). The noninferiority margin was -10 percentage points. Secondary outcomes included scores on memory tests and patient-reported quality of life. After the initial treatment phase, the patients who had a response were followed over a 6-month period. RESULTS: A total of 403 patients underwent randomization at five clinical sites; 200 patients were assigned to the ketamine group and 203 to the ECT group. After 38 patients had withdrawn before initiation of the assigned treatment, ketamine was administered to 195 patients and ECT to 170 patients. A total of 55.4% of the patients in the ketamine group and 41.2% of those in the ECT group had a response (difference, 14.2 percentage points; 95% confidence interval, 3.9 to 24.2; P<0.001 for the noninferiority of ketamine to ECT). ECT appeared to be associated with a decrease in memory recall after 3 weeks of treatment (mean [±SE] decrease in the T-score for delayed recall on the Hopkins Verbal Learning Test-Revised, -0.9±1.1 in the ketamine group vs. -9.7±1.2 in the ECT group; scores range from -300 to 200, with higher scores indicating better function) with gradual recovery during follow-up. Improvement in patient-reported quality-of-life was similar in the two trial groups. ECT was associated with musculoskeletal adverse effects, whereas ketamine was associated with dissociation. CONCLUSIONS: Ketamine was noninferior to ECT as therapy for treatment-resistant major depression without psychosis. (Funded by the Patient-Centered Outcomes Research Institute; ELEKT-D ClinicalTrials.gov number, NCT03113968.).


Asunto(s)
Antidepresivos , Trastorno Depresivo Resistente al Tratamiento , Terapia Electroconvulsiva , Ketamina , Humanos , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/terapia , Terapia Electroconvulsiva/efectos adversos , Ketamina/administración & dosificación , Ketamina/efectos adversos , Ketamina/uso terapéutico , Calidad de Vida , Resultado del Tratamiento , Antidepresivos/administración & dosificación , Antidepresivos/efectos adversos , Antidepresivos/uso terapéutico , Trastorno Depresivo Resistente al Tratamiento/diagnóstico , Trastorno Depresivo Resistente al Tratamiento/tratamiento farmacológico , Trastorno Depresivo Resistente al Tratamiento/terapia , Administración Intravenosa , Trastornos Psicóticos
4.
Ann Behav Med ; 58(5): 363-374, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38489667

RESUMEN

BACKGROUND: Despite the benefits of exercise, many individuals are unable or unwilling to adopt an exercise intervention. PURPOSE: The purpose of this analysis was to identify putative genetic variants associated with dropout from exercise training interventions among individuals in the STRRIDE trials. METHODS: We used a genome-wide association study approach to identify genetic variants in 603 participants initiating a supervised exercise intervention. Exercise intervention dropout occurred when a subject withdrew from further participation in the study or was otherwise lost to follow-up. RESULTS: Exercise intervention dropout was associated with a cluster of single-nucleotide polymorphisms with the top candidate being rs722069 (T/C, risk allele = C) (unadjusted p = 2.2 × 10-7, odds ratio = 2.23) contained within a linkage disequilibrium block on chromosome 16. In Genotype-Tissue Expression, rs722069 is an expression quantitative trait locus of the EARS2, COG7, and DCTN5 genes in skeletal muscle tissue. In subsets of the STRRIDE genetic cohort with available muscle gene expression (n = 37) and metabolic data (n = 82), at baseline the C allele was associated with lesser muscle expression of EARS2 (p < .002) and COG7 (p = .074) as well as lesser muscle concentrations of C2- and C3-acylcarnitines (p = .026). CONCLUSIONS: Our observations imply that exercise intervention dropout is genetically moderated through alterations in gene expression and metabolic pathways in skeletal muscle. Individual genetic traits may allow the development of a biomarker-based approach for identifying individuals who may benefit from more intensive counseling and other interventions to optimize exercise intervention adoption. CLINICAL TRIAL INFORMATION: STRRIDE I = NCT00200993; STRRIDE AT/RT = NCT00275145; STRRIDE-PD = NCT00962962.


Regular participation in exercise can provide a myriad of health benefits. Although individuals recognize these benefits, many are unable or unwilling to adopt an exercise intervention once initiated. The purpose of this analysis was to identify genetic variants associated with dropout from an exercise training intervention. We found exercise intervention dropout to be genetically moderated through changes in gene expression and metabolic pathways in muscle. Thus, individual genetic traits may allow for the development of a biomarker-based targeted approach for identifying individuals who may benefit from more intensive counseling and interventions to optimize the adoption of an exercise intervention program.


Asunto(s)
Enfermedades Cardiovasculares , Sobrepeso , Adulto , Humanos , Estudio de Asociación del Genoma Completo , Obesidad , Terapia por Ejercicio
5.
Proc Natl Acad Sci U S A ; 118(27)2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34187888

RESUMEN

Recent progress in DNA synthesis and sequencing technology has enabled systematic studies of protein function at a massive scale. We explore a deep mutational scanning study that measured the transcriptional repression function of 43,669 variants of the Escherichia coli LacI protein. We analyze structural and evolutionary aspects that relate to how the function of this protein is maintained, including an in-depth look at the C-terminal domain. We develop a deep neural network to predict transcriptional repression mediated by the lac repressor of Escherichia coli using experimental measurements of variant function. When measured across 10 separate training and validation splits using 5,009 single mutations of the lac repressor, our best-performing model achieved a median Pearson correlation of 0.79, exceeding any previous model. We demonstrate that deep representation learning approaches, first trained in an unsupervised manner across millions of diverse proteins, can be fine-tuned in a supervised fashion using lac repressor experimental datasets to more effectively predict a variant's effect on repression. These findings suggest a deep representation learning model may improve the prediction of other important properties of proteins.


Asunto(s)
Aprendizaje Profundo , Proteínas de Escherichia coli/metabolismo , Represoras Lac/metabolismo , Transcripción Genética , Epistasis Genética , Proteínas de Escherichia coli/genética , Represoras Lac/genética , Mutación/genética , Dominios Proteicos , Reproducibilidad de los Resultados
6.
Cereb Cortex ; 32(23): 5285-5300, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-35257146

RESUMEN

Patients with obsessive-compulsive disorder (OCD) exhibit abnormality in their subjective perception of internal sensation, a process known as interoceptive sensibility (IS), as well as altered functioning of the insula, a key neural structure for interoception. We investigated the multivariate structure of IS in 77 OCD patients and 53 controls and examined associations of IS with resting-state functional connectivity (FC) of the insula within the OCD group. For each group, principal component analysis was performed on 8 subscales of the Multidimensional Assessment of Interoceptive Awareness assessing putatively "adaptive" and "maladaptive" aspects of IS. Associations between IS components and insula FC in the OCD group were evaluated using seed regions placed in each of 3 subdivisions of the insula (posterior, anterior dorsal, and anterior ventral). Behaviorally, controls showed a 2-component solution broadly categorized into "adaptive" and "maladaptive" IS, while OCD patients exhibited a 3-component solution. The general tendency to notice or be aware of sensation loaded onto an "adaptive" IS component in controls but loaded onto both "adaptive" and "maladaptive" IS components in OCD. Within OCD, insula FC was differentially associated with distinct aspects of IS, identifying network connections that could serve as future targets for the modulation of IS in OCD.


Asunto(s)
Interocepción , Trastorno Obsesivo Compulsivo , Humanos , Imagen por Resonancia Magnética/métodos , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Sensación , Mapeo Encefálico , Vías Nerviosas/diagnóstico por imagen
7.
Proc Natl Acad Sci U S A ; 117(41): 25396-25401, 2020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-33024018

RESUMEN

Quantum computers and simulators may offer significant advantages over their classical counterparts, providing insights into quantum many-body systems and possibly improving performance for solving exponentially hard problems, such as optimization and satisfiability. Here, we report the implementation of a low-depth Quantum Approximate Optimization Algorithm (QAOA) using an analog quantum simulator. We estimate the ground-state energy of the Transverse Field Ising Model with long-range interactions with tunable range, and we optimize the corresponding combinatorial classical problem by sampling the QAOA output with high-fidelity, single-shot, individual qubit measurements. We execute the algorithm with both an exhaustive search and closed-loop optimization of the variational parameters, approximating the ground-state energy with up to 40 trapped-ion qubits. We benchmark the experiment with bootstrapping heuristic methods scaling polynomially with the system size. We observe, in agreement with numerics, that the QAOA performance does not degrade significantly as we scale up the system size and that the runtime is approximately independent from the number of qubits. We finally give a comprehensive analysis of the errors occurring in our system, a crucial step in the path forward toward the application of the QAOA to more general problem instances.

8.
Learn Mem ; 29(2): 38-47, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35042827

RESUMEN

Fear is an adaptive emotion that serves to protect an organism against potential dangers. It is often studied using classical conditioning paradigms where a conditioned stimulus is paired with an aversive unconditioned stimulus to induce a threat response. Less commonly studied is a phenomenon that is related to this form of conditioning, known as latent inhibition. Latent inhibition (LI) is a paradigm in which a neutral cue is repeatedly presented in the absence of any aversive associations. Subsequent pairing of this pre-exposed cue with an aversive stimulus typically leads to reduced expression of a conditioned fear/threat response. In this article, we review some of the theoretical basis for LI and its behavioral and neural mechanisms. We compare and contrast LI and fear/threat extinction-a process in which a previously conditioned cue is repeatedly presented in the absence of aversive outcomes. We end with highlighting the potential clinical utility of LI. Particularly, we focus on how LI application could be useful for enhancing resilience, especially for individuals who are more prone to continuous exposure to trauma and stressful environments, such as healthcare workers and first responders. The knowledge to be gained from advancing our understanding of neural mechanisms in latent inhibition could be applicable across psychiatric disorders characterized by exaggerated fear responses and impaired emotion regulation.


Asunto(s)
Condicionamiento Clásico , Miedo , Emociones , Extinción Psicológica , Humanos , Memoria
9.
J Paediatr Child Health ; 58(8): 1414-1419, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35502826

RESUMEN

AIM: Penicillin allergy accounts for the majority of all reported adverse drug reactions in adults and children. Foregoing first-line antibiotic therapy due to penicillin allergy label is associated with an increased prevalence of infections by resistant organisms and longer hospitalisation. Clinician awareness of allergy assessment, referral indications, management of allergy and anaphylaxis is therefore vital but globally lacking. We aim to assess the knowledge of penicillin allergy, assessment and management in Western Australian health professionals. METHODS: An anonymous survey was distributed to pharmacists, nurses and physicians within Western Australian paediatric and adult Hospitals, Community and General Practice. RESULTS: In total, 487/611 were completed and included in the statistical analysis. Only 62% (301/487) of respondents routinely assessed for patient medication allergies. Of those who assessed allergy, 9% (28/301) of respondents met the Australian standards for allergy assessment. Only 22% (106/487) of participants correctly cited all indications for management with adrenaline in anaphylaxis to antibiotics and 67% (197/292) of physicians rarely or never referred to an allergy service. Paediatric clinicians had an increased understanding of allergy assessment and anaphylaxis management. Recent penicillin allergy education within a 5-year period led to significant improvements in allergy knowledge. CONCLUSION: Overall, knowledge, assessment and management of penicillin allergies among practitioners in Western Australia are currently inadequate in adults and paediatric clinicians to provide safe and effective clinical care. The implementation of a targeted education program for WA health professionals is urgently required and is expected to improve clinician knowledge and aid standardised penicillin assessment (de-labelling) practices.


Asunto(s)
Anafilaxia , Hipersensibilidad a las Drogas , Adulto , Anafilaxia/tratamiento farmacológico , Antibacterianos/efectos adversos , Australia , Niño , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/terapia , Hospitales , Humanos , Penicilinas/efectos adversos , Encuestas y Cuestionarios
10.
Fam Community Health ; 45(2): 59-66, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35125488

RESUMEN

Mixed-status families-whose members have multiple immigration statuses-are common in US immigrant communities. Large-scale worksite raids, an immigration enforcement tactic used throughout US history, returned during the Trump administration. Yet, little research characterizes the impacts of these raids, especially as related to mixed-status families. The current study (1) describes a working definition of a large-scale worksite raid and (2) considers impacts of these raids on mixed-status families. We conducted semistructured interviews in Spanish and English at 6 communities that experienced the largest worksite raids in 2018. Participants were 77 adults who provided material, emotional, or professional support following raids. Qualitative analysis methods were used to develop a codebook and code all interviews. The unpredictability of worksite raids resulted in chaos and confusion, often stemming from potential family separation. Financial crises followed because of the removal of primary financial providers. In response, families rearranged roles to generate income. Large-scale worksite raids result in similar harms to mixed-status families as other enforcement tactics but on a much larger scale. They also uniquely drain community resources, with long-term impacts. Advocacy and policy efforts are needed to mitigate damage and end this practice.


Asunto(s)
Emigrantes e Inmigrantes , Emigración e Inmigración , Adulto , Relaciones Familiares , Hispánicos o Latinos , Humanos , Lugar de Trabajo
11.
Mol Psychiatry ; 25(6): 1323-1333, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-30385872

RESUMEN

Major depressive disorder (MDD) is a leading cause of disability worldwide, yet current treatment strategies remain limited in their mechanistic diversity. Recent evidence has highlighted a promising novel pharmaceutical target-the KCNQ-type potassium channel-for the treatment of depressive disorders, which may exert a therapeutic effect via functional changes within the brain reward system, including the ventral striatum. The current study assessed the effects of the KCNQ channel opener ezogabine (also known as retigabine) on reward circuitry and clinical symptoms in patients with MDD. Eighteen medication-free individuals with MDD currently in a major depressive episode were enrolled in an open-label study and received ezogabine up to 900 mg/day orally over the course of 10 weeks. Resting-state functional magnetic resonance imaging data were collected at baseline and posttreatment to examine brain reward circuitry. Reward learning was measured using a computerized probabilistic reward task. After treatment with ezogabine, subjects exhibited a significant reduction of depressive symptoms (Montgomery-Asberg Depression Rating Scale score change: -13.7 ± 9.7, p < 0.001, d = 2.08) and anhedonic symptoms (Snaith-Hamilton Pleasure Scale score change: -6.1 ± 5.3, p < 0.001, d = 1.00), which remained significant even after controlling for overall depression severity. Improvement in depression was associated with decreased functional connectivity between the ventral caudate and clusters within the mid-cingulate cortex and posterior cingulate cortex (n = 14, voxel-wise p < 0.005). In addition, a subgroup of patients tested with a probabilistic reward task (n = 9) showed increased reward learning following treatment. These findings highlight the KCNQ-type potassium channel as a promising target for future drug discovery efforts in mood disorders.


Asunto(s)
Carbamatos/farmacología , Carbamatos/uso terapéutico , Trastorno Depresivo Mayor/tratamiento farmacológico , Activación del Canal Iónico/efectos de los fármacos , Fenilendiaminas/farmacología , Fenilendiaminas/uso terapéutico , Estriado Ventral/efectos de los fármacos , Trastorno Depresivo Mayor/metabolismo , Femenino , Humanos , Canales de Potasio KCNQ/agonistas , Canales de Potasio KCNQ/metabolismo , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recompensa , Estriado Ventral/metabolismo
12.
RNA Biol ; 18(sup2): 770-781, 2021 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-34719327

RESUMEN

TUT4 and the closely related TUT7 are non-templated poly(U) polymerases required at different stages of development, and their mis-regulation or mutation has been linked to important cancer pathologies. While TUT4(7) interaction with its pre-miRNA targets has been characterized in detail, the molecular bases of the broader target recognition process are unclear. Here, we examine RNA binding by the ZnF domains of the protein. We show that TUT4(7) ZnF2 contains two distinct RNA binding surfaces that are used in the interaction with different RNA nucleobases in different targets, i.e that this small domain encodes diversity in TUT4(7) selectivity and molecular function. Interestingly and unlike other well-characterized CCHC ZnFs, ZnF2 is not physically coupled to the flanking ZnF3 and acts independently in miRNA recognition, while the remaining CCHC ZnF of TUT4(7), ZnF1, has lost its intrinsic RNA binding capability. Together, our data suggest that the ZnFs of TUT4(7) are independent units for RNA and, possibly, protein-protein interactions that underlay the protein's functional flexibility and are likely to play an important role in building its interaction network.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Epistasis Genética , Regulación de la Expresión Génica , MicroARNs/genética , Proteínas de Unión al ARN/metabolismo , Dedos de Zinc , Composición de Base , Proteínas de Unión al ADN/química , Humanos , Espectroscopía de Resonancia Magnética , MicroARNs/química , MicroARNs/metabolismo , Poli U , Dominios y Motivos de Interacción de Proteínas , Proteínas de Unión al ARN/química , Relación Estructura-Actividad
13.
Hum Brain Mapp ; 41(6): 1611-1625, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-31916668

RESUMEN

Obsessive-compulsive disorder (OCD) is highly heterogeneous. While obsessions often involve fear of harm, many patients report uncomfortable sensations and/or urges that drive repetitive behaviors in the absence of a specific fear. Prior work suggests that urges in OCD may be similar to everyday "urges-for-action" (UFA) such as the urge to blink, swallow, or scratch, but very little work has investigated the pathophysiology underlying urges in OCD. In the current study, we used an urge-to-blink approach to model sensory-based urges that could be experimentally elicited and compared across patients and controls using the same task stimuli. OCD patients and controls suppressed eye blinking over a period of 60 s, alternating with free blinking blocks, while brain activity was measured using functional magnetic resonance imaging. OCD patients showed significantly increased activation in several regions during the early phase of eyeblink suppression (first 30 s), including mid-cingulate, insula, striatum, parietal cortex, and occipital cortex, with lingering group differences in parietal and occipital regions during late eyeblink suppression (last 30 s). There were no differences in brain activation during free blinking blocks, and no conditions where OCD patients showed reduced activation compared to controls. In an exploratory analysis of blink counts performed in a subset of subjects, OCD patients were less successful than controls in suppressing blinks. These data indicate that OCD patients exhibit altered brain function and behavior when experiencing and suppressing the urge to blink, raising the possibility that the disorder is associated with a general abnormality in the UFA system that could ultimately be targeted by future treatments.


Asunto(s)
Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/psicología , Adulto , Ansiedad/diagnóstico por imagen , Ansiedad/psicología , Parpadeo , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Mapeo Encefálico , Depresión/diagnóstico por imagen , Depresión/psicología , Femenino , Humanos , Modelos Lineales , Imagen por Resonancia Magnética , Masculino , Motivación , Neuroimagen , Represión Psicológica
14.
Nucleic Acids Res ; 45(11): 6761-6774, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-28379442

RESUMEN

RBM10 is an RNA-binding protein that plays an essential role in development and is frequently mutated in the context of human disease. RBM10 recognizes a diverse set of RNA motifs in introns and exons and regulates alternative splicing. However, the molecular mechanisms underlying this seemingly relaxed sequence specificity are not understood and functional studies have focused on 3΄ intronic sites only. Here, we dissect the RNA code recognized by RBM10 and relate it to the splicing regulatory function of this protein. We show that a two-domain RRM1-ZnF unit recognizes a GGA-centered motif enriched in RBM10 exonic sites with high affinity and specificity and test that the interaction with these exonic sequences promotes exon skipping. Importantly, a second RRM domain (RRM2) of RBM10 recognizes a C-rich sequence, which explains its known interaction with the intronic 3΄ site of NUMB exon 9 contributing to regulation of the Notch pathway in cancer. Together, these findings explain RBM10's broad RNA specificity and suggest that RBM10 functions as a splicing regulator using two RNA-binding units with different specificities to promote exon skipping.


Asunto(s)
Proteínas de Unión al ARN/fisiología , Autoantígenos , Secuencia de Bases , Sitios de Unión , Exones , Células HEK293 , Humanos , Unión Proteica , Empalme del ARN , ARN Mensajero/química , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/química , Dedos de Zinc
15.
Clin Chem ; 64(1): 99-107, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29158251

RESUMEN

BACKGROUND: Overweight and obesity are significant public health concerns that are linked to numerous negative health consequences. Physical activity is an important lifestyle behavior that contributes to body weight regulation. CONTENT: Physical activity is inversely associated with weight gain and the incidence of obesity. Physical activity also contributes to additional weight loss when coupled with dietary modification, and it can result in modest weight loss when not coupled with dietary modification. Moreover, physical activity is associated with improved long-term weight loss and prevention of weight gain following initial weight loss. Current evidence supports that physical activity should be moderate to vigorous in intensity to influence body weight regulation. There is also a growing body of evidence that physical activity can be accumulated throughout the day in shorter periods of time rather than being performed during a structured and longer period, and that physical activity performed in this manner can be important for body weight regulation. SUMMARY: The literature supports the inclusion of physical activity as an important lifestyle behavior for regulating body weight. There are multiple intervention approaches that may be effective for enhancing physical activity engagement within the context of weight control.


Asunto(s)
Ejercicio Físico , Obesidad/terapia , Sobrepeso/terapia , Dieta , Metabolismo Energético , Humanos , Estilo de Vida , Síndrome Metabólico/epidemiología , Obesidad/epidemiología , Obesidad/fisiopatología , Sobrepeso/epidemiología , Sobrepeso/fisiopatología , Prevalencia , Factores de Riesgo , Aumento de Peso , Pérdida de Peso
16.
Int J Neuropsychopharmacol ; 21(1): 3-11, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29186416

RESUMEN

Background: Anxiety and trauma-related disorders are among the most prevalent and disabling medical conditions in the United States, and posttraumatic stress disorder in particular exacts a tremendous public health toll. We examined the tolerability and anxiolytic efficacy of neuropeptide Y administered via an intranasal route in patients with posttraumatic stress disorder. Methods: Twenty-six individuals were randomized in a cross-over, single ascending dose study into 1 of 5 cohorts: 1.4 mg (n=3), 2.8 mg (n=6), 4.6 mg (n=5), 6.8 mg (n=6), and 9.6 mg (n=6). Each individual was dosed with neuropeptide Y or placebo on separate treatment days 1 week apart in random order under double-blind conditions. Assessments were conducted at baseline and following a trauma script symptom provocation procedure subsequent to dosing. Occurrence of adverse events represented the primary tolerability outcome. The difference between treatment conditions on anxiety as measured by the Beck Anxiety Inventory and the State-Trait Anxiety Inventory immediately following the trauma script represented efficacy outcomes. Results: Twenty-four individuals completed both treatment days. Neuropeptide Y was well tolerated up to and including the highest dose. There was a significant interaction between treatment and dose; higher doses of neuropeptide Y were associated with a greater treatment effect, favoring neuropeptide Y over placebo on Beck Anxiety Inventory score (F1,20=4.95, P=.038). There was no significant interaction for State-Trait Anxiety Inventory score. Conclusions: Our study suggests that a single dose of neuropeptide Y is well tolerated up to 9.6 mg and may be associated with anxiolytic effects. Future studies exploring the safety and efficacy of neuropeptide Y in stress-related disorders are warranted. The reported study is registered at: http://clinicaltrials.gov (ID: NCT01533519).


Asunto(s)
Neuropéptido Y/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Trastornos por Estrés Postraumático/tratamiento farmacológico , Adulto , Ansiedad/tratamiento farmacológico , Estudios de Cohortes , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Escalas de Valoración Psiquiátrica , Resultado del Tratamiento
17.
Aust N Z J Obstet Gynaecol ; 58(3): 291-297, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28901544

RESUMEN

BACKGROUND: Rates of pre-gestational obesity and gestational diabetes mellitus (GDM) are increasing in Australia. While both are established risk factors for neonatal hypoglycaemia, the additive effect of both risks on neonatal hypoglycaemia is not well understood. AIMS: To determine the influence of obesity on neonatal hypoglycaemia among infants born to GDM mothers. The authors hypothesise the presence of a greater frequency and severity of neonatal hypoglycaemia in infants born to obese GDM women. MATERIALS AND METHODS: A cohort of 471 singleton GDM pregnancies was retrospectively studied. Women were divided into obese (body mass index (BMI) ≥ 30 kg/m2 ) and not-obese (BMI < 30 kg/m2 ) groups according to self-reported pre-pregnancy weight. Perinatal outcomes and details of hypoglycaemic episodes were obtained by reviewing medical records. RESULTS: Twenty-five percent (104/410) of the GDM mothers were obese, while 36% (146/410) exceeded pregnancy weight gain recommendations. GDM and obesity resulted in a greater frequency of neonatal hypoglycaemia as compared to women with GDM alone (obese 44%, not obese 34%, P = 0.046). Obesity increased the likelihood of having multiple hypoglycaemic episodes (P = 0.022). Excess weight gain increased the likelihood of the neonate requiring intravenous dextrose (P = 0.0012). No differences were found in the likelihood of nursery admissions or lowest plasma glucose levels. CONCLUSIONS: Pre-pregnancy obesity and weight gain during pregnancy above the recommended limits increased the likelihood of neonatal hypoglycaemia among infants of GDM mothers. Further studies with larger cohorts are warranted to confirm our findings.


Asunto(s)
Diabetes Gestacional/epidemiología , Ganancia de Peso Gestacional , Hipoglucemia/epidemiología , Enfermedades del Recién Nacido/epidemiología , Obesidad , Adulto , Diabetes Gestacional/sangre , Femenino , Humanos , Hipoglucemia/sangre , Recién Nacido , Enfermedades del Recién Nacido/sangre , Embarazo , Atención Prenatal , Estudios Retrospectivos , Factores de Riesgo , Australia Occidental/epidemiología
18.
Nucleic Acids Res ; 43(6): e41, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-25586222

RESUMEN

Defining the RNA target selectivity of the proteins regulating mRNA metabolism is a key issue in RNA biology. Here we present a novel use of principal component analysis (PCA) to extract the RNA sequence preference of RNA binding proteins. We show that PCA can be used to compare the changes in the nuclear magnetic resonance (NMR) spectrum of a protein upon binding a set of quasi-degenerate RNAs and define the nucleobase specificity. We couple this application of PCA to an automated NMR spectra recording and processing protocol and obtain an unbiased and high-throughput NMR method for the analysis of nucleobase preference in protein-RNA interactions. We test the method on the RNA binding domains of three important regulators of RNA metabolism.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento/métodos , Resonancia Magnética Nuclear Biomolecular/métodos , Proteínas de Unión al ARN/metabolismo , ARN/genética , ARN/metabolismo , Secuencia de Bases , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Ensayos Analíticos de Alto Rendimiento/estadística & datos numéricos , Humanos , Modelos Moleculares , Análisis de Componente Principal , Dominios y Motivos de Interacción de Proteínas , Proteínas de Unión al ARN/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Factores de Escisión y Poliadenilación de ARNm/química , Factores de Escisión y Poliadenilación de ARNm/metabolismo
19.
Hum Brain Mapp ; 37(9): 3214-23, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27144347

RESUMEN

BACKGROUND: Major depressive disorder is a disabling neuropsychiatric condition that is associated with disrupted functional connectivity across brain networks. The precise nature of altered connectivity, however, remains incompletely understood. The current study was designed to examine the coherence of large-scale connectivity in depression using a recently developed technique termed global brain connectivity. METHODS: A total of 82 subjects, including medication-free patients with major depression (n = 57) and healthy volunteers (n = 25) underwent functional magnetic resonance imaging with resting data acquisition for functional connectivity analysis. Global brain connectivity was computed as the mean of each voxel's time series correlation with every other voxel and compared between study groups. Relationships between global connectivity and depressive symptom severity measured using the Montgomery-Åsberg Depression Rating Scale were examined by means of linear correlation. RESULTS: Relative to the healthy group, patients with depression evidenced reduced global connectivity bilaterally within multiple regions of medial and lateral prefrontal cortex. The largest between-group difference was observed within the right subgenual anterior cingulate cortex, extending into ventromedial prefrontal cortex bilaterally (Hedges' g = -1.48, P < 0.000001). Within the depressed group, patients with the lowest connectivity evidenced the highest symptom severity within ventromedial prefrontal cortex (r = -0.47, P = 0.0005). CONCLUSIONS: Patients with major depressive evidenced abnormal large-scale functional coherence in the brain that was centered within the subgenual cingulate cortex, and medial prefrontal cortex more broadly. These data extend prior studies of connectivity in depression and demonstrate that functional disconnection of the medial prefrontal cortex is a key pathological feature of the disorder. Hum Brain Mapp 37:3214-3223, 2016. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Trastorno Depresivo Mayor/fisiopatología , Vías Nerviosas/fisiopatología , Corteza Prefrontal/fisiopatología , Adulto , Mapeo Encefálico , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
20.
Mol Phylogenet Evol ; 99: 16-33, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26953739

RESUMEN

The Hawaiian mints (Lamiaceae), one of the largest endemic plant lineages in the archipelago, provide an excellent system to study rapid diversification of a lineage with a remote, likely paleohybrid origin. Since their divergence from New World mints 4-5 million years ago the members of this lineage have diversified greatly and represent a remarkable array of vegetative and reproductive phenotypes. Today many members of this group are endangered or already extinct, and molecular phylogenetic work relies largely on herbarium samples collected during the last century. So far a gene-by-gene approach has been utilized, but the recent radiation of the Hawaiian mints has resulted in minimal sequence divergence and hence poor phylogenetic resolution. In our quest to trace the reticulate evolutionary history of the lineage, a resolved maternal phylogeny is necessary. We applied a high-throughput approach to sequence 12 complete or nearly complete plastid genomes from multiple Hawaiian mint species and relatives, including extinct and rare taxa. We also targeted 108 hypervariable regions from throughout the chloroplast genomes in nearly all of the remaining Hawaiian species, and relatives, using a next-generation amplicon sequencing approach. This procedure generated ∼20Kb of sequence data for each taxon and considerably increased the total number of variable sites over previous analyses. Our results demonstrate the potential of high-throughput sequencing of historic material for evolutionary studies in rapidly evolving lineages. Our study, however, also highlights the challenges of resolving relationships within recent radiations even at the genomic level.


Asunto(s)
Especies en Peligro de Extinción , Extinción Biológica , Genoma de Plastidios , Mentha/genética , Filogenia , Plastidios/genética , Emparejamiento Base/genética , Secuencia de Bases , Daño del ADN , Hawaii , Análisis de Secuencia de ADN
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