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1.
Phys Rev E ; 109(1-2): 015105, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38366535

RESUMO

The viscosity and thermal conductivity coefficients of the Lennard-Jones fluid are extracted through symbolic regression (SR) techniques from data derived from simulations at the atomic scale. This data-oriented approach provides closed form relations that achieve fine accuracy when compared to well-established theoretical, empirical, or approximate equations, fully transparent, with small complexity and high interpretability. The novelty is further outlined by suggesting analytical expressions for estimating fluid transport properties across the whole phase space, from a dilute gas to a dense liquid, by considering only two macroscopic properties (density and temperature). In such expressions, the underlying physical mechanisms are reflected, while, at the same time, it can be a computationally efficient alternative to costly in time and size first principle and/or molecular dynamics simulations.

3.
Front Pediatr ; 11: 1321296, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38105790

RESUMO

Background: The process of morbidity and mortality review (MMR) is recognized as an essential component of quality improvement, patient safety, attitudes towards patient safety, and continuing education. Despite the common use of MMR for all disciplines of medical care, recommendations have not been published regarding the implementation of MMR in a community hospital setting in the United States. Objectives: Review the literature on MMR conferences. Describe the implementation of an MMR conference in a community hospital neonatal intensive care unit (NICU). Conclusions: The establishment of a case overview method of MMR is feasible for a community hospital NICU. It increases staff and physician group awareness and education over common and complex mortality and morbidity etiologies, improves staff participation with unit management, links case presentation with open discussion and action items, and identifies opportunities for systemic changes to improve patient care.

4.
Cardiol Young ; : 1-6, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37822191

RESUMO

BACKGROUND: In neonatal vein of Galen aneurysmal malformation, vein of Galen aneurysmal malformation echocardiography remains the mainstay for early detection and explains various haemodynamic changes occurring due to a large systemic arterio-venous shunt. However, there is limited evidence of echocardiography in risk stratifying neonatal vein of Galen aneurysmal malformation vein of Galen aneurysmal malformation. The objective of this study was to identify echocardiographic parameters that could be associated with major outcomes and guide timing of neuro-intervention. METHODS: In this retrospective chart review, infants < 28 days of age with the diagnosis of vein of Galen aneurysmal malformation vein of Galen aneurysmal malformation were included. Demographic, clinical, and echocardiographic parameters were compared in neonates who survived or died with neonatal presentation. A risk algorithm model based on key echocardiographic parameters was developed to determine those who are at risk of early death. RESULTS: Of the 19 neonates included, with median birth weight 3.1 kg (IQR 2.58-3.36), nine (47%) neonates died at median age of 5 days (IQR 4-17). All neonates showed retrograde diastolic flow at the level of descending aorta by colour Doppler on the first post-natal echocardiogram at median age of 2 days (IQR 1-5.5). An aortic antegrade-to-retrograde velocity time integral ratio of < 1.5 and supra-systemic pulmonary artery pressure had 100% positive predictive value of death (p = 0.029), whereas aortic antegrade-to-retrograde velocity time integral ratio of > 1.5 and sub-systemic pulmonary artery pressure had 100% positive predictive value of survival (p = 0.029). CONCLUSION: Combination of aorta antegrade-to-retrograde velocity time integral ratio and degree of pulmonary hypertension on the first post-natal echocardiogram may help stratify the severity of disease and guide optimal timing for neuro-intervention for neonatal vein of Galen aneurysmal malformation.

5.
bioRxiv ; 2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37398172

RESUMO

Invadopodia are extracellular matrix (ECM) degrading structures, which promote cancer cell invasion. The nucleus is increasingly viewed as a mechanosensory organelle that determines migratory strategies. However, how the nucleus crosstalks with invadopodia is little known. Here, we report that the oncogenic septin 9 isoform 1 (SEPT9_i1) is a component of breast cancer invadopodia. SEPT9_i1 depletion diminishes invadopodia formation and the clustering of invadopodia precursor components TKS5 and cortactin. This phenotype is characterized by deformed nuclei, and nuclear envelopes with folds and grooves. We show that SEPT9_i1 localizes to the nuclear envelope and juxtanuclear invadopodia. Moreover, exogenous lamin A rescues nuclear morphology and juxtanuclear TKS5 clusters. Importantly, SEPT9_i1 is required for the amplification of juxtanuclear invadopodia, which is induced by the epidermal growth factor. We posit that nuclei of low deformability favor the formation of juxtanuclear invadopodia in a SEPT9_i1-dependent manner, which functions as a tunable mechanism for overcoming ECM impenetrability. Highlights: The oncogenic SEPT9_i1 is enriched in breast cancer invadopodia in 2D and 3D ECMSEPT9_i1 promotes invadopodia precursor clustering and invadopodia elongationSEPT9_i1 localizes to the nuclear envelope and reduces nuclear deformabilitySEPT9_i1 is required for EGF-induced amplification of juxtanuclear invadopodia. eTOC Blurb: Invadopodia promote the invasion of metastatic cancers. The nucleus is a mechanosensory organelle that determines migratory strategies, but how it crosstalks with invadopodia is unknown. Okletey et al show that the oncogenic isoform SEPT9_i1 promotes nuclear envelope stability and the formation of invadopodia at juxtanuclear areas of the plasma membrane.

6.
Micromachines (Basel) ; 14(7)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37512757

RESUMO

In this paper, we propose an alternative road to calculate the transport coefficients of fluids and the slip length inside nano-conduits in a Poiseuille-like geometry. These are all computationally demanding properties that depend on dynamic, thermal, and geometrical characteristics of the implied fluid and the wall material. By introducing the genetic programming-based method of symbolic regression, we are able to derive interpretable data-based mathematical expressions based on previous molecular dynamics simulation data. Emphasis is placed on the physical interpretability of the symbolic expressions. The outcome is a set of mathematical equations, with reduced complexity and increased accuracy, that adhere to existing domain knowledge and can be exploited in fluid property interpolation and extrapolation, bypassing timely simulations when possible.

7.
Cell Rep ; 42(8): 112893, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37516960

RESUMO

Invadopodia are extracellular matrix (ECM) degrading structures, which promote cancer cell invasion. The nucleus is increasingly viewed as a mechanosensory organelle that determines migratory strategies. However, how the nucleus crosstalks with invadopodia is little known. Here, we report that the oncogenic septin 9 isoform 1 (SEPT9_i1) is a component of breast cancer invadopodia. SEPT9_i1 depletion diminishes invadopodium formation and the clustering of the invadopodium precursor components TKS5 and cortactin. This phenotype is characterized by deformed nuclei and nuclear envelopes with folds and grooves. We show that SEPT9_i1 localizes to the nuclear envelope and juxtanuclear invadopodia. Moreover, exogenous lamin A rescues nuclear morphology and juxtanuclear TKS5 clusters. Importantly, SEPT9_i1 is required for the amplification of juxtanuclear invadopodia, which is induced by the epidermal growth factor. We posit that nuclei of low deformability favor the formation of juxtanuclear invadopodia in a SEPT9_i1-dependent manner, which functions as a tunable mechanism for overcoming ECM impenetrability.


Assuntos
Neoplasias da Mama , Podossomos , Humanos , Feminino , Septinas/metabolismo , Podossomos/metabolismo , Isoformas de Proteínas/metabolismo , Neoplasias da Mama/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Linhagem Celular Tumoral , Invasividade Neoplásica
8.
Arch Comput Methods Eng ; : 1-21, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37359747

RESUMO

Symbolic regression (SR) is a machine learning-based regression method based on genetic programming principles that integrates techniques and processes from heterogeneous scientific fields and is capable of providing analytical equations purely from data. This remarkable characteristic diminishes the need to incorporate prior knowledge about the investigated system. SR can spot profound and elucidate ambiguous relations that can be generalizable, applicable, explainable and span over most scientific, technological, economical, and social principles. In this review, current state of the art is documented, technical and physical characteristics of SR are presented, the available programming techniques are investigated, fields of application are explored, and future perspectives are discussed. Supplementary Information: The online version contains supplementary material available at 10.1007/s11831-023-09922-z.

9.
Pediatr Res ; 94(3): 892-903, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37120652

RESUMO

Hyperglycemia is commonly encountered in extremely preterm newborns and physiologically can be attributed to immaturity in several biochemical pathways related to glucose metabolism. Although hyperglycemia is associated with a variety of adverse outcomes frequently described in this population, evidence for causality is lacking. Variations in definitions and treatment approaches have further complicated the understanding and implications of hyperglycemia on the immediate and long-term effects in preterm newborns. In this review, we describe the relationship between hyperglycemia and organ development, outcomes, treatment options, and potential gaps in knowledge that need further research. IMPACT: Hyperglycemia is common and less well described than hypoglycemia in extremely preterm newborns. Hyperglycemia can be attributed to immaturity in several cellular pathways involved in glucose metabolism in this age group. Hyperglycemia has been shown to be associated with a variety of adverse outcomes frequently described in this population; however, evidence for causality is lacking. Variations in definitions and treatment approaches have complicated the understanding and the implications of hyperglycemia on the immediate and long-term effects outcomes. This review describes the relationship between hyperglycemia and organ development, outcomes, treatment options, and potential gaps in knowledge that need further research.


Assuntos
Hiperglicemia , Hipoglicemia , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Hiperglicemia/complicações , Hiperglicemia/terapia , Causalidade , Hipoglicemia/complicações , Glucose , Glicemia/metabolismo
10.
Pediatr Res ; 93(1): 39-48, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35422084

RESUMO

Neonates who present in high output heart failure secondary to vein of Galen aneurysmal malformation can be difficult to manage medically due to the complex physiology that results from the large shunt through the malformation. Though the cardiac function is often normal, right ventricular dilation, severe pulmonary hypertension, and systemic steal can result in inadequate organ perfusion and shock. This report recommends medical management for stabilization of neonates prior to definitive management with endovascular embolization. IMPACT: Vein of Galen aneurysmal malformation (VGAM) is a rare intracranial arteriovenous malformation, which can present in the neonatal period with high output heart failure. Heart failure secondary to VGAM is often difficult to manage and is associated with high mortality and morbidity. Despite optimal medical management, many patients require urgent endovascular embolization for stabilization of their heart failure. This report offers discrete recommendations that can be used by clinicians as guidelines for the medical management of heart failure in newborns with VGAM.


Assuntos
Veias Cerebrais , Insuficiência Cardíaca , Doenças do Recém-Nascido , Malformações Arteriovenosas Intracranianas , Malformações da Veia de Galeno , Humanos , Recém-Nascido , Veias Cerebrais/anormalidades , Malformações da Veia de Galeno/complicações , Malformações da Veia de Galeno/diagnóstico por imagem , Malformações da Veia de Galeno/terapia , Malformações Arteriovenosas Intracranianas/complicações , Insuficiência Cardíaca/terapia
11.
J Perinatol ; 42(12): 1576-1586, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36376450

RESUMO

Thyroid hormones play an important role in the development and function of the cardiac myocyte. Dysregulation of the thyroid hormone milieu affects the fetal cardiac cells via complex molecular mechanisms, either by altering gene expression or directly by affecting post-translational processes. This review offers a comprehensive summary of the effects of thyroid hormones on the developing cardiovascular system and its adaptation. Furthermore, we will highlight the gaps in knowledge and provide suggestions for future research.


Assuntos
Glândula Tireoide , Hormônios Tireóideos , Humanos , Recém-Nascido , Feto , Coração
12.
Cureus ; 14(9): e29412, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36304346

RESUMO

Wellens' syndrome (WS) is a pattern on an electrocardiogram (ECG) characterized by biphasic T waves or deeply inverted T waves in leads V2-V3 with a recent clinical history of angina. Wellens' pattern on the ECG is particular for critical left anterior descending artery (LAD) stenosis. Wellens' sign and WS have been used interchangeably in the literature. However, the typical patterns of ECG changes noted are mostly represented by Wellens' sign. These ECG changes have been crucial in identifying this subset of patients with severe LAD disease.

13.
Cureus ; 14(3): e23561, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35494949

RESUMO

Our patient was a 56-year-old Caucasian female who had 34 emergency department visits to our center with recurrent chest pain, of which eleven were of cardiac etiology, involving cardiac causes over the period of seven years. Her chest pain was diagnosed as atypical during her previous visits. Chest CT revealed "ace-of-spades" in the cardiac transverse section. A transthoracic echocardiogram (TTE) demonstrated apical hypertrophy with end-systolic cavity obliteration and an ejection fraction (EF) of 65%-70%, seated amidst a normal-sized left ventricle, with normal wall thickness, indicating Yamaguchi syndrome. In the case report, we portray the need to widen the spectrum of differentials in an encounter with a patient presenting with chest pain.

18.
Curr Protoc ; 1(2): e51, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33587334

RESUMO

Evaluation of in vivo potencies plays an important role in drug discovery. Traditionally, the cellular activity and percent of plasma protein binding of a test agent are evaluated separately, with the plasma protein binding-adjusted cellular potency computation used to estimate in vivo potency. This process is costly, takes weeks to complete, and is increasingly unreliable for compounds that bind extensively to plasma proteins. Described in this article is a simple, high-throughput human plasma in-cell Western (ICW) assay that directly incorporates plasma protein binding into a cellular pharmacodynamic assay to provide a rapid and accurate estimate of in vivo potencies. The assay is versatile and can be readily employed for various targets that require short treatment periods for displaying maximal biological responses. © 2021 Wiley Periodicals LLC. Basic Protocol: Concentration-dependent human plasma ICW assay to determine test compound IC50 against the target of interest.


Assuntos
Bioensaio , Descoberta de Drogas , Proteínas Sanguíneas/metabolismo , Humanos , Ligação Proteica
19.
Pediatr Res ; 89(4): 738-745, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32563183

RESUMO

Apart from its known actions as a pulmonary vasodilator, nitric oxide (NO) is a key signal mediator in the neonatal brain. Despite the extensive use of NO for pulmonary artery hypertension (PAH), its actions in the setting of brain hypoxia and ischemia, which co-exists with PAH in 20-30% of affected infants, are not well established. This review focuses on the mechanisms of actions of NO covering the basic, translational, and clinical evidence of its neuroprotective and neurotoxic properties. In this first part, we present the physiology of transport and delivery of NO to the brain and the regulation of cerebrovascular and systemic circulation by NO, as well the role of NO in the development of the immature brain. IMPACT: NO can be transferred from the site of production to the site of action rapidly and affects the central nervous system. Inhaled NO (iNO), a commonly used medication, can have significant effects on the neonatal brain. NO regulates the cerebrovascular and systemic circulation and plays a role in the development of the immature brain. This review describes the properties of NO under physiologic conditions and under stress. The impact of this review is that it describes the effects of NO, especially regarding the vulnerable neonatal brain, and helps understand the conditions that could contribute to neurotoxicity or neuroprotection.


Assuntos
Encéfalo/embriologia , Encéfalo/metabolismo , Óxido Nítrico/metabolismo , Administração por Inalação , Animais , Transporte Biológico , Circulação Cerebrovascular , Humanos , Hipertensão Pulmonar , Hipóxia Encefálica , Hipóxia-Isquemia Encefálica , Oxigênio/metabolismo , Estresse Fisiológico
20.
Pediatr Res ; 89(4): 746-752, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32563184

RESUMO

Nitric oxide (NO) has critical roles in a wide variety of key biologic functions and has intricate transport mechanisms for delivery to key distal tissues under normal conditions. However, NO also plays important roles during disease processes, such as hypoxia-ischemia, asphyxia, neuro-inflammation, and retinopathy of prematurity. The effects of exogenous NO on the developing neonatal brain remain controversial. Inhaled NO (iNO) can be neuroprotective or toxic depending on a variety of factors, including cellular redox state, underlying disease processes, duration of treatment, and dose. This review identifies key gaps in knowledge that should prompt further investigation into the possible role of iNO as a therapeutic agent after injury to the brain. IMPACT: NO is a key signal mediator in the neonatal brain with neuroprotective and neurotoxic properties. iNO, a commonly used medication, has significant effects on the neonatal brain. Dosing, duration, and timing of administration of iNO can affect the developing brain. This review article summarizes the roles of NO in association with various disease processes that impact neonates, such as brain hypoxia-ischemia, asphyxia, retinopathy of prematurity, and neuroinflammation. The impact of this review is that it clearly describes gaps in knowledge, and makes the case for further, targeted studies in each of the identified areas.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Encéfalo/metabolismo , Administração por Inalação , Animais , Animais Recém-Nascidos , Asfixia/metabolismo , Encéfalo/efeitos dos fármacos , Humanos , Hipóxia , Hipóxia-Isquemia Encefálica , Recém-Nascido , Doenças do Recém-Nascido , Doenças do Prematuro/tratamento farmacológico , Inflamação , Doenças Neuroinflamatórias , Óxido Nítrico/administração & dosagem , Óxido Nítrico/metabolismo
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