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1.
Heart Lung Circ ; 33(6): 764-772, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38565438

RESUMO

The percutaneous management of chronic total occlusions (CTO) is a well-established sub-specialty of Interventional Cardiology, requiring specialist equipment, training, and techniques. The heterogeneity of approaches in CTO has led to the generation of multiple algorithms to guide operators in their management. The evidence base for management of CTOs has suffered from inconsistent descriptive and quantitative terminology in defining the nature of lesions and techniques utilised, as well as seemingly contradictory data about improvement in ventricular function, symptoms of angina, and mortality from large-scale registries and randomised controlled trials. Through this review, we explore the history of CTO management and its supporting evidence in detail, with an outline of limitations of CTO-percutaneous coronary intervention and a look at the future of this growing field within cardiology.


Assuntos
Oclusão Coronária , Intervenção Coronária Percutânea , Humanos , Oclusão Coronária/diagnóstico , Oclusão Coronária/terapia , Oclusão Coronária/cirurgia , Intervenção Coronária Percutânea/métodos , Doença Crônica
2.
New Phytol ; 238(3): 952-970, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36694296

RESUMO

Wildfires are a global crisis, but current fire models fail to capture vegetation response to changing climate. With drought and elevated temperature increasing the importance of vegetation dynamics to fire behavior, and the advent of next generation models capable of capturing increasingly complex physical processes, we provide a renewed focus on representation of woody vegetation in fire models. Currently, the most advanced representations of fire behavior and biophysical fire effects are found in distinct classes of fine-scale models and do not capture variation in live fuel (i.e. living plant) properties. We demonstrate that plant water and carbon dynamics, which influence combustion and heat transfer into the plant and often dictate plant survival, provide the mechanistic linkage between fire behavior and effects. Our conceptual framework linking remotely sensed estimates of plant water and carbon to fine-scale models of fire behavior and effects could be a critical first step toward improving the fidelity of the coarse scale models that are now relied upon for global fire forecasting. This process-based approach will be essential to capturing the influence of physiological responses to drought and warming on live fuel conditions, strengthening the science needed to guide fire managers in an uncertain future.


Assuntos
Incêndios , Incêndios Florestais , Plantas , Fenômenos Fisiológicos Vegetais , Água , Carbono , Ecossistema
3.
J Neurooncol ; 163(3): 529-539, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37440095

RESUMO

PURPOSE: Social determinants of health broadly affect healthcare access and outcomes. Studies report that minorities and low socioeconomic status (SES) patients undergoing intracranial meningioma resection demonstrate worse outcomes and higher mortality rates. This systematic review and meta-analysis summarizes the available research reporting racial and SES disparities in intracranial meningioma resection outcomes. METHODS: A systematic review was conducted using PRISMA guidelines and included peer-reviewed, English-language articles from the United States between 2000 and 2022 that reported racial and SES disparities in meningioma outcomes. Outcomes included overall survival (OS), extent of resection (EOR), hospitalization costs, length of stay (LOS), 30-day readmission, recurrence, and receipt of surgery and adjuvant radiotherapy. A quantitative meta-analysis was performed only on survival outcomes by race. All other variables were summarized as a systematic review. RESULTS: 633 articles were identified; 19 studies met inclusion criteria. Black or low SES patients were more likely to have increased hospitalization costs, rates of 30-day readmission, LOS, recurrence and less likely to undergo surgery, gross total resection, and adjuvant radiotherapy for their tumors. Six studies were used for the quantitative meta-analysis of race and OS. Compared to White patients, Black patients had significantly worse survival outcomes, and Asian patients had significantly better survival outcomes. CONCLUSION: Disparities in outcomes exist for patients who undergo surgery for meningioma, such that Black and low SES patients have worse outcomes. The literature is quite sparse and contains confounding relationships not often accounted for appropriately. Further studies are needed to help understand these disparities to improve outcomes.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Estados Unidos , Meningioma/patologia , Classe Social , Hospitalização , Tempo de Internação , Neoplasias Meníngeas/patologia , Disparidades em Assistência à Saúde
4.
J Neurooncol ; 162(2): 253-265, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37010677

RESUMO

INTRODUCTION: Surgical resection has long been the treatment of choice for meningiomas and is considered curative in many cases. Indeed, the extent of resection (EOR) remains a significant factor in determining disease recurrence and outcome optimization for patients undergoing surgery. Although the Simpson Grading Scale continues to be widely accepted as the measure of EOR and is used to predict symptomatic recurrence, its utility is under increasing scrutiny. The influence of surgery in the definitive management of meningioma is being re-appraised considering the rapid evolution of our understanding of the biology of meningioma. DISCUSSION: Although historically considered "benign" lesions, meningioma natural history can vary greatly, behaving with unexpectedly high recurrence rates and growth which do not always behave in accordance with their WHO grade. Histologically confirmed WHO grade 1 tumors may demonstrate unexpected recurrence, malignant transformation, and aggressive behavior, underscoring the molecular complexity and heterogeneity. CONCLUSION: As our understanding of the clinical predictive power of genomic and epigenomic factors matures, we here discuss the importance of surgical decision-making paradigms in the context of our rapidly evolving understanding of these molecular features.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/genética , Meningioma/cirurgia , Meningioma/patologia , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/cirurgia , Recidiva Local de Neoplasia/patologia , Procedimentos Neurocirúrgicos , Estudos Retrospectivos
5.
J Neurooncol ; 164(2): 299-308, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37624530

RESUMO

PURPOSE: Frailty has gained prominence in neurosurgical oncology, with more studies exploring its relationship to postoperative outcomes in brain tumor patients. As this body of literature continues to grow, concisely reviewing recent developments in the field is necessary. Here we provide a systematic review of frailty in brain tumor patients subdivided by tumor type, incorporating both modern frailty indices and traditional Karnofsky Performance Status (KPS) metrics. METHODS: Systematic literature review was performed using PRISMA guidelines. PubMed and Google Scholar were queried for articles related to frailty, KPS, and brain tumor outcomes. Only articles describing novel associations between frailty or KPS and primary intracranial tumors were included. RESULTS: After exclusion criteria, systematic review yielded 52 publications. Amongst malignant lesions, 16 studies focused on glioblastoma. Amongst benign tumors, 13 focused on meningiomas, and 6 focused on vestibular schwannomas. Seventeen studies grouped all brain tumor patients together. Seven studies incorporated both frailty indices and KPS into their analyses. Studies correlated frailty with various postoperative outcomes, including complications and mortality. CONCLUSION: Our review identified several patterns of overall postsurgical outcomes reporting for patients with brain tumors and frailty. To date, reviews of frailty in patients with brain tumors have been largely limited to certain frailty indices, analyzing all patients together regardless of lesion etiology. Although this technique is beneficial in providing a general overview of frailty's use for brain tumor patients, given each tumor pathology has its own unique etiology, this combined approach potentially neglects key nuances governing frailty's use and prognostic value.


Assuntos
Neoplasias Encefálicas , Fragilidade , Neoplasias Meníngeas , Humanos , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/cirurgia , Fragilidade/complicações , Neoplasias Meníngeas/cirurgia , Complicações Pós-Operatórias/etiologia , Prognóstico , Resultado do Tratamento
6.
Philos Trans A Math Phys Eng Sci ; 380(2214): 20210120, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34802273

RESUMO

We describe the population-based susceptible-exposed-infected-removed (SEIR) model developed by the Irish Epidemiological Modelling Advisory Group (IEMAG), which advises the Irish government on COVID-19 responses. The model assumes a time-varying effective contact rate (equivalently, a time-varying reproduction number) to model the effect of non-pharmaceutical interventions. A crucial technical challenge in applying such models is their accurate calibration to observed data, e.g. to the daily number of confirmed new cases, as the history of the disease strongly affects predictions of future scenarios. We demonstrate an approach based on inversion of the SEIR equations in conjunction with statistical modelling and spline-fitting of the data to produce a robust methodology for calibration of a wide class of models of this type. This article is part of the theme issue 'Data science approaches to infectious disease surveillance'.


Assuntos
COVID-19 , Suscetibilidade a Doenças , Humanos , Modelos Estatísticos , SARS-CoV-2
7.
Dev Psychopathol ; 34(3): 1064-1078, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-33436142

RESUMO

Adolescent females are at elevated risk for the development of depression. In this study, we addressed two questions: Are pubertal hormones associated with adolescent mental health? Might this association depend on pubertal development? We tested the hypothesis that estradiol, which has been associated with adolescent social sensitivity, might interact with pubertal stage to predict depression risk at three time points in ninth and tenth grade. Hormones and pubertal development were measured ninth-grade females. Linear regression analyses were used to predict fall ninth-grade (N = 79), spring ninth-grade (N = 76), and spring tenth-grade (N = 67) Children's Depression Inventory (CDI) scores. The hypothesized model was not statistically significant, but exploratory analyses revealed that two- and three-way interactions incorporating estradiol, puberty (stage and perceived onset), and cortisol predicted current and future CDI scores. Our exploratory model did not predict changes in CDI but did account for future (spring of ninth grade) CDI scores. Specifically, estradiol was positively correlated with fall and spring ninth-grade depressive symptoms in participants with high cortisol who also reported earlier stages and later perceived onset of pubertal development. These findings suggest that hormones associated with sensitivity to the social environment deserve consideration in models of adolescent depression risk.


Assuntos
Depressão , Hidrocortisona , Adolescente , Criança , Depressão/diagnóstico , Estradiol , Feminino , Humanos , Puberdade/psicologia , Instituições Acadêmicas
8.
Proc Natl Acad Sci U S A ; 116(51): 25535-25545, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31767750

RESUMO

In recent years, the field of psychology has begun to conduct replication tests on a large scale. Here, we show that "replicator degrees of freedom" make it far too easy to obtain and publish false-negative replication results, even while appearing to adhere to strict methodological standards. Specifically, using data from an ongoing debate, we show that commonly exercised flexibility at the experimental design and data analysis stages of replication testing can make it appear that a finding was not replicated when, in fact, it was. The debate that we focus on is representative, on key dimensions, of a large number of other replication tests in psychology that have been published in recent years, suggesting that the lessons of this analysis may be far reaching. The problems with current practice in replication science that we uncover here are particularly worrisome because they are not adequately addressed by the field's standard remedies, including preregistration. Implications for how the field could develop more effective methodological standards for replication are discussed.


Assuntos
Pesquisa Biomédica/normas , Psicologia/métodos , Reprodutibilidade dos Testes , Projetos de Pesquisa/normas , Interpretação Estatística de Dados , Humanos , Inquéritos e Questionários
9.
Proc Natl Acad Sci U S A ; 116(47): 23534-23541, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31591207

RESUMO

Mitochondrial superoxide dismutase (SOD2) suppresses tumor initiation but promotes invasion and dissemination of tumor cells at later stages of the disease. The mechanism of this functional switch remains poorly defined. Our results indicate that as SOD2 expression increases acetylation of lysine 68 ensues. Acetylated SOD2 promotes hypoxic signaling via increased mitochondrial reactive oxygen species (mtROS). mtROS, in turn, stabilize hypoxia-induced factor 2α (HIF2α), a transcription factor upstream of "stemness" genes such as Oct4, Sox2, and Nanog. In this sense, our findings indicate that SOD2K68Ac and mtROS are linked to stemness reprogramming in breast cancer cells via HIF2α signaling. Based on these findings we propose that, as tumors evolve, the accumulation of SOD2K68Ac turns on a mitochondrial pathway to stemness that depends on HIF2α and may be relevant for the progression of breast cancer toward poor outcomes.


Assuntos
Neoplasias da Mama/patologia , Autorrenovação Celular/fisiologia , Proteínas de Neoplasias/fisiologia , Células-Tronco Neoplásicas/fisiologia , Superóxido Dismutase/fisiologia , Acetilação , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Neoplasias da Mama/metabolismo , Reprogramação Celular , Progressão da Doença , Feminino , Xenoenxertos , Humanos , Peróxido de Hidrogênio/metabolismo , Células MCF-7 , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mitocôndrias/enzimologia , Invasividade Neoplásica , Proteínas de Neoplasias/química , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/metabolismo , Superóxido Dismutase/química
10.
Chembiochem ; 22(9): 1609-1620, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33480159

RESUMO

Regulator of G protein signaling (RGS) proteins have attracted attention as a result of their primary role in directing the specificity as well as the temporal and spatial aspects of G protein-coupled receptor signaling. In addition, alterations in RGS protein expression have been observed in a number of disease states, including certain cancers. In this area, RGS17 is of particular interest. It has been demonstrated that, while RGS17 is expressed primarily in the central nervous system, it has been found to be inappropriately expressed in lung, prostate, breast, cervical, and hepatocellular carcinomas. Overexpression of RGS17 leads to dysfunction in inhibitory G protein signaling and an overproduction of the intracellular second messenger cAMP, which in turn alters the transcription patterns of proteins known to promote various cancer types. Suppressing RGS17 expression with RNA interference (RNAi) has been found to decrease tumorigenesis and sufficiently prevents cancer cell migration, leading to the hypothesis that pharmacological blocking of RGS17 function could be useful in anticancer therapies. We have identified small-molecule fragments capable of binding the RGS homology (RH) domain of RGS17 by using a nuclear magnetic resonance fragment-based screening approach. By chemical shift mapping of the two-dimensional 15 N,1 H heteronuclear single quantum coherence (HSQC) spectra of the backbone-assigned 15 N-labeled RGS17-RH, we determined the fragment binding sites to be distant from the Gα interface. Thus, our study identifies a putative fragment binding site on RGS17 that was previously unknown.


Assuntos
Ressonância Magnética Nuclear Biomolecular , Proteínas RGS/metabolismo , Sítios de Ligação , Humanos , Cinética , Mutagênese Sítio-Dirigida , Estabilidade Proteica , Proteínas RGS/antagonistas & inibidores , Proteínas RGS/genética , Transdução de Sinais , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo
11.
New Phytol ; 231(5): 1676-1685, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34105789

RESUMO

The dead foliage of scorched crowns is one of the most conspicuous signatures of wildland fires. Globally, crown scorch from fires in savannas, woodlands and forests causes tree stress and death across diverse taxa. The term crown scorch, however, is inconsistently and ambiguously defined in the literature, causing confusion and conflicting interpretation of results. Furthermore, the underlying mechanisms causing foliage death from fire are poorly understood. The consequences of crown scorch - alterations in physiological, biogeochemical and ecological processes and ecosystem recovery pathways - remain largely unexamined. Most research on the topic assumes the mechanism of leaf and bud death is exposure to lethal air temperatures, with few direct measurements of lethal heating thresholds. Notable information gaps include how energy transfer injures and kills leaves and buds, how nutrients, carbohydrates, and hormones respond, and what physiological consequences lead to mortality. We clarify definitions to encourage use of unified terminology for foliage and bud necrosis resulting from fire. We review the current understanding of the physical mechanisms driving foliar injury, discuss the physiological responses, and explore novel ecological consequences of crown injury from fire. From these elements, we propose research needs for the increasingly interdisciplinary study of fire effects.


Assuntos
Incêndios , Incêndios Florestais , Ecossistema , Florestas , Árvores
12.
Glob Chang Biol ; 27(4): 713-715, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064872

RESUMO

Fill et al. (Global Change Biology, 25, 3562-3569, 2019) reported significant increases in dry season length over the past 120 years in the Southeast US, suggesting increased wildfire risk in a region associated with a frequent fire regime. We identified two flaws that call into question the findings and their relevance to regional wildfire risk. First, with the exception of Florida, there is little evidence for a climatologically meaningful 'dry season' in the Southeast because most areas experience relatively evenly distributed monthly precipitation. Second, the sampling method used to derive Cumulative Rainfall Anomalies does not appear to actually reflect a bootstrap sample as described.


Assuntos
Mudança Climática , Raio , Florida , Estações do Ano , Sudeste dos Estados Unidos
13.
Psychol Sci ; 32(3): 354-363, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33533309

RESUMO

Some leaders display high levels of narcissism. Does the link between narcissism levels and leadership exist in childhood? We conducted, to our knowledge, the first study of the relationship between narcissism levels and various aspects of leadership in children (N = 332, ages 7-14 years). We assessed narcissism levels using the Childhood Narcissism Scale and assessed leadership emergence in classrooms using peer nominations. Children then performed a group task in which one child was randomly assigned as leader. We assessed perceived and actual leadership functioning. Children with higher narcissism levels more often emerged as leaders in classrooms. When given a leadership role in the task, children with higher narcissism levels perceived themselves as better leaders, but their actual leadership functioning did not differ significantly from that of other leaders. Specification-curve analyses corroborated these findings. Thus, children with relatively high narcissism levels tend to emerge as leaders, even though they may not excel as leaders.


Assuntos
Liderança , Narcisismo , Adolescente , Criança , Humanos , Personalidade
14.
Sensors (Basel) ; 21(6)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803711

RESUMO

Sensible energy is the primary mode of heat dissipation from combustion in wildland surface fires. However, despite its importance to fire dynamics, smoke transport, and in determining ecological effects, it is not routinely measured. McCaffrey and Heskestad (A robust bidirectional low-velocity probe for flame and fire application. Combustion and Flame 26:125-127, 1976) describe measurements of flame velocity from a bi-directional probe which, when combined with gas temperature measurements, can be used to estimate sensible heat fluxes. In this first field application of bi-directional probes, we describe vertical and horizontal sensible heat fluxes during the RxCADRE experimental surface fires in longleaf pine savanna and open ranges at Eglin Air Force Base, Florida. Flame-front sensible energy is the time-integral of heat flux over a residence time, here defined by the rise in gas temperatures above ambient. Horizontal flow velocities and energies were larger than vertical velocities and energies. Sensible heat flux and energy measurements were coordinated with overhead radiometer measurements from which we estimated fire energy (total energy generated by combustion) under the assumption that 17% of fire energy is radiated. In approximation, horizontal, vertical, and resultant sensible energies averaged 75%, 54%, and 64%, respectively, of fire energy. While promising, measurement challenges remain, including obtaining accurate gas and velocity measurements and capturing three-dimensional flow in the field.

15.
J Biol Chem ; 294(49): 18571-18585, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31636120

RESUMO

G protein-coupled receptors (GPCRs) play critical roles in regulating processes such as cellular homeostasis, responses to stimuli, and cell signaling. Accordingly, GPCRs have long served as extraordinarily successful drug targets. It is therefore not surprising that the discovery in the mid-1990s of a family of proteins that regulate processes downstream of GPCRs generated great excitement in the field. This finding enhanced the understanding of these critical signaling pathways and provided potentially new targets for pharmacological intervention. These regulators of G-protein signaling (RGS) proteins were viewed by many as nodes downstream of GPCRs that could be targeted with small molecules to tune signaling processes. In this review, we provide a brief overview of the discovery of RGS proteins and of the gradual and continuing discovery of their roles in disease states, focusing particularly on cancer and neurological disorders. We also discuss high-throughput screening efforts that have led to the discovery first of peptide-based and then of small-molecule inhibitors targeting a subset of the RGS proteins. We explore the unique mechanisms of RGS inhibition these chemical tools have revealed and highlight the most up-to-date studies using these tools in animal experiments. Finally, we discuss the future opportunities in the field, as there are clearly more avenues left to be explored and potentials to be realized.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Proteínas RGS/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Proteínas de Ligação ao GTP/química , Humanos , Estrutura Secundária de Proteína , Proteínas RGS/química , Receptores Acoplados a Proteínas G/química , Transdução de Sinais
16.
J Biol Chem ; 294(20): 8148-8160, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-30940727

RESUMO

Regulator of G protein signaling (RGS) proteins are negative regulators of G protein-coupled receptor (GPCR) signaling through their ability to act as GTPase-activating proteins (GAPs) for activated Gα subunits. Members of the RZ subfamily of RGS proteins bind to activated Gαo, Gαz, and Gαi1-3 proteins in the nervous system and thereby inhibit downstream pathways, including those involved in Ca2+-dependent signaling. In contrast to other RGS proteins, little is known about RZ subfamily structure and regulation. Herein, we present the 1.5-Å crystal structure of RGS17, the most complete and highest-resolution structure of an RZ subfamily member to date. RGS17 cocrystallized with Ca2+ bound to conserved positions on the predicted Gα-binding surface of the protein. Using NMR chemical shift perturbations, we confirmed that Ca2+ binds in solution to the same site. Furthermore, RGS17 had greater than 55-fold higher affinity for Ca2+ than for Mg2+ Finally, we found that Ca2+ promotes interactions between RGS17 and activated Gα and decreases the Km for GTP hydrolysis, potentially by altering the binding mechanism between these proteins. Taken together, these findings suggest that Ca2+ positively regulates RGS17, which may represent a general mechanism by which increased Ca2+ concentration promotes the GAP activity of the RZ subfamily, leading to RZ-mediated inhibition of Ca2+ signaling.


Assuntos
Sinalização do Cálcio , Cálcio/química , Proteínas RGS/química , Cálcio/metabolismo , Cristalografia por Raios X , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Guanosina Trifosfato/química , Guanosina Trifosfato/genética , Guanosina Trifosfato/metabolismo , Humanos , Hidrólise , Magnésio/química , Magnésio/metabolismo , Proteínas RGS/genética , Proteínas RGS/metabolismo
17.
Child Dev ; 91(6): 2141-2159, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32892358

RESUMO

Three studies examined the effects of receiving fewer signs of positive feedback than others on social media. In Study 1, adolescents (N = 613, Mage  = 14.3 years) who were randomly assigned to receive few (vs. many) likes during a standardized social media interaction felt more strongly rejected, and reported more negative affect and more negative thoughts about themselves. In Study 2 (N = 145), negative responses to receiving fewer likes were associated with greater depressive symptoms reported day-to-day and at the end of the school year. Study 3 (N = 579) replicated Study 1's main effect of receiving fewer likes and showed that adolescents who already experienced peer victimization at school were the most vulnerable. The findings raise the possibility that technology which makes it easier for adolescents to compare their social status online-even when there is no chance to share explicitly negative comments-could be a risk factor that accelerates the onset of internalizing symptoms among vulnerable youth.


Assuntos
Angústia Psicológica , Psicologia do Adolescente , Mídias Sociais , Adolescente , Bullying/psicologia , Criança , Vítimas de Crime/psicologia , Feminino , Humanos , Masculino , Grupo Associado , Distância Psicológica , Instituições Acadêmicas
18.
J Chem Phys ; 152(18): 184108, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32414239

RESUMO

PSI4 is a free and open-source ab initio electronic structure program providing implementations of Hartree-Fock, density functional theory, many-body perturbation theory, configuration interaction, density cumulant theory, symmetry-adapted perturbation theory, and coupled-cluster theory. Most of the methods are quite efficient, thanks to density fitting and multi-core parallelism. The program is a hybrid of C++ and Python, and calculations may be run with very simple text files or using the Python API, facilitating post-processing and complex workflows; method developers also have access to most of PSI4's core functionalities via Python. Job specification may be passed using The Molecular Sciences Software Institute (MolSSI) QCSCHEMA data format, facilitating interoperability. A rewrite of our top-level computation driver, and concomitant adoption of the MolSSI QCARCHIVE INFRASTRUCTURE project, makes the latest version of PSI4 well suited to distributed computation of large numbers of independent tasks. The project has fostered the development of independent software components that may be reused in other quantum chemistry programs.

19.
J Bioenerg Biomembr ; 49(4): 325-333, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28616679

RESUMO

It is becoming increasingly clear that mitochondria drive cellular functions and in vivo phenotypes by directing the production rate and abundance of metabolites that are proposed to function as signaling molecules (Chandel 2015; Selak et al. 2005; Etchegaray and Mostoslavsky 2016). Many of these metabolites are intermediates that make up cellular metabolism, part of which occur in mitochondria (i.e. the TCA and urea cycles), while others are produced "on demand" mainly in response to alterations in the microenvironment in order to participate in the activation of acute adaptive responses (Mills et al. 2016; Go et al. 2010). Reactive oxygen species (ROS) are well suited for the purpose of executing rapid and transient signaling due to their short lived nature (Bae et al. 2011). Hydrogen peroxide (H2O2), in particular, possesses important characteristics including diffusibility and faster reactivity with specific residues such as methionine, cysteine and selenocysteine (Bonini et al. 2014). Therefore, it is reasonable to propose that H2O2 functions as a relatively specific redox signaling molecule. Even though it is now established that mtH2O2 is indispensable, at least for hypoxic adaptation and energetic and/or metabolic homeostasis (Hamanaka et al. 2016; Guzy et al. 2005), the question of how H2O2 is produced and regulated in the mitochondria is only partially answered. In this review, some roles of this indispensable signaling molecule in driving cellular metabolism will be discussed. In addition, we will discuss how H2O2 formation in mitochondria depends on and is controlled by MnSOD. Finally, we will conclude this manuscript by highlighting why a better understanding of redox hubs in the mitochondria will likely lead to new and improved therapeutics of a number of diseases, including cancer.


Assuntos
Mitocôndrias/metabolismo , Transdução de Sinais , Superóxido Dismutase/fisiologia , Animais , Humanos , Peróxido de Hidrogênio/metabolismo , Oxirredução
20.
Anal Biochem ; 522: 10-17, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28115169

RESUMO

Cell based assessment tools and screening platforms are the preferred paradigm for small molecule identification and validation due to selectively identifying molecules with cellular activity and validation of compound activity against target proteins in their native environment. With respect to Regulator of G Protein Signaling (RGS) proteins, current cell based methodologies are either low throughput or monitor downstream signaling consequences. The increasing number of reports indicating RGS function in various disease pathogeneses highlights the need for a robust RGS inhibitor discovery and characterization paradigm. Promega's NanoBit Protein Complementation Assay utilizes NanoLuc, an engineered luciferase with enhanced luminescence characteristics which allow for both robust and kinetic assessment of protein interaction formation and disruption. Here we characterized 15 separate RGS: G protein interactions using this system. The binding profile of RGS: Gα interactions correlates to prior published biochemical binding profiles of these proteins. Additionally, we demonstrated this system is suitable for high throughput screening efforts via calculation of Z-factors for three of the interactions and demonstrated that a known small molecule inhibitor of RGS4 disrupts the RGS4: Gαi1 protein-protein interaction. In conclusion, the NanoBit Protein Complementation Assay holds promise as a robust platform for discovery and characterization of RGS inhibitors.


Assuntos
Bioensaio/métodos , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Medições Luminescentes/métodos , Proteínas RGS/metabolismo , Animais , Linhagem Celular , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Humanos , Proteínas RGS/genética , Ratos
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