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• Unlike common neural network models, we propose a new whole heart segmentation framework based on improved Deep Forest, which is interpretable. It adopts the idea of ensemble learning and combines the methods of bagging and boosting. • We employ hybrid feature fusion, multi-scale fusion and multi-resolution fusion to increase model diversity and segmentation accuracy, and further compare different feature's importance. • Compared to the neural network models, our model can complete training in a shorter time and is more efficient. Automatic whole heart segmentation plays an important role in the treatment and research of cardiovascular diseases. In this paper, we propose an improved Deep Forest framework, named Multi-Resolution Deep Forest Framework (MRDFF), which accomplishes whole heart segmentation in two stages. We extract the heart region by binary classification in the first stage, thus avoiding the class imbalance problem caused by too much background. The results of the first stage are then subdivided in the second stage to obtain accurate cardiac substructures. In addition, we also propose hybrid feature fusion, multi-resolution fusion and multi-scale fusion to further improve the segmentation accuracy. Experiments on the public dataset MM-WHS show that our model can achieve comparable accuracy in about half the training time of neural network models. [ABSTRACT FROM AUTHOR]

Claudin-5 (CLDN5) is an essential component of tight junctions (TJs) and is critical for the integrity of the blood-brain barrier (BBB), ensuring homeostasis and protection from damage to the central nervous system (CNS). Currently, many researchers have summarized the role and mechanisms of CLDN5 in CNS diseases. However, it is noteworthy that CLDN5 also plays a significant role in tumor growth and metastasis. In addition, abnormal CLDN5 expression is involved in the development of respiratory diseases, intestinal diseases, cardiac diseases, and diabetic ocular complications. This paper aims to review the structure, expression, and regulation of CLDN5, focusing on its role in tumors, including its expression and regulation, effects on malignant phenotypes, and clinical significance. Furthermore, this paper will provide an overview of the role and mechanisms of CLDN5 in respiratory diseases, intestinal diseases, cardiac diseases, and diabetic ocular complications. [Display omitted] [ABSTRACT FROM AUTHOR]

Direct cardiac reprogramming, which refers to somatic cell (i.e. fibroblast) fate conversion to cardiomyocyte-like cell without transitioning through an intermediate pluripotent state, provides a novel therapeutic strategy for heart regeneration by converting resident cardiac fibroblasts to cardiomyocytes in situ. However, several limitations need to be addressed prior to clinical translation of this technology. They include low efficiency of reprogramming, heterogeneity of starting fibroblasts, functional immaturity of induced cardiomyocytes (iCMs), virus immunogenicity and toxicity, incomplete understanding of changes in the epigenetic landscape as fibroblasts undergo reprogramming, and the environmental factors that influence fate conversion. Several studies have demonstrated that a combination of enforced expression of cardiac transcription factors along with certain cytokines and growth factors in the presence of favorable environmental cues (including extracellular matrix, topography, and mechanical properties) enhance the efficiency and quality of direct reprogramming. This paper reviews the literature on the influence of the microenvironment on direct cardiac reprogramming in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Fibrosis refers to the phenomenon that fibrous connective tissues are increased and parenchymal cells are decreased in organs or tissues such as lung, heart, liver, kidney, skin and so on. It usually occurs at the late stage of repair of chronic or recurrent tissue damage. Fibrotic disease is the main factor for the morbidity and mortality of all tissues and organ systems. Long-term fibrosis can lead to organ and tissue dysfunction and even failure. Interleukin −1 family cytokines are a series of classical inflammatory factors and involved in the occurrence and development process of multiple fibrotic diseases, its biological function, relationship with diseases and application are more and more favored by scientists from various countries. So far, 11 cytokines and 10 receptors of IL-1 family have been identified. In this paper, the cytokines, receptors, signaling pathways and biological functions of IL-1 family are summarized, and the correlation with fibrosis diseases is analyzed. [ABSTRACT FROM AUTHOR]

In most developed countries, cardiovascular diseases are among the top causes of death and their development has been shown closely related to aging. In this context, because of their ability to pervasively influence gene networks, miRs have been found as possible key players in the development of cardiac pathologies, suggesting their potential role as therapeutic targets or diagnostic markers. Based on these assumptions, we hereby present a computational study that applies data fusion techniques coupled with network analysis theory to identify a regulatory model able to represent the relationship between key genes and miRs involved in cardiac senescence processes. The proposed model has been validated through an extensive literature analysis, which confirmed that 94% of the identified genes and miRs are related with cardiac senescence. Furthermore, two relevant genes of the model have been also validated by Western blot experiments on heart samples from young and old mice, confirming in vitro their ectopic expression in aged hearts. The pure computationally inferred model presented in the paper is therefore a good candidate to represent the relationship between key genes and miRs involved in cardiac senescence processes, and represents a reliable selection of genes and miRs for further studies, in order to elucidate and better detail their involvement in cardiac aging. [ABSTRACT FROM AUTHOR]

In an earlier paper (Cohen and Bergman, Am. J. Physiol. 268 (1995) E397), we explored the relationship between the exponents in the exponential curve fit to isotopic enrichment versus time and the fractional turnover rate of the largest metabolic pool in the pathway. Here we present the analysis on a more rigorous footing and apply it to questions of cerebral and cardiac metabolism. Our emphasis in this paper is to describe and justify mathematically an approach for analysis of metabolic dynamics, not with the intention of replacing the use of numerical software for estimation of flux rates but for giving the scientist the opportunity to examine the system in an approximate manner, and thereby to check not only that the results of the numerical solution are the correct solutions to the equations but also that the equations portray the correct simplification of the metabolic pathway.We introduce the “dominant rate constant” as a tool for deriving algebraic formulas relating rates of metabolic flux, sizes of metabolic pools, and the dynamics of isotopic enrichment. Illustrations of such algebraic formulas are provided for the rates of the citric acid cycle (CAC), glycolysis and glutamine synthesis in brain, as well as the rate of the CAC in heart. In addition, we prove that formulas for estimation of rates of glycolysis and of the CAC depend critically on the fractional turnover rates of lactate and glutamate, respectively.The justification for analysis of simulated data is that we are studying the effects of simplifications of metabolic models on the accuracy of estimation of metabolic pathways. Our use of the dominant rate constant is an analytical convenience that allows us to assess proposed simplifications of metabolic pathways. [Copyright &y& Elsevier]

Abstract: Heterocellular electrotonic coupling between cardiac myocytes and non-excitable connective tissue cells has been a long-established and well-researched fact in vitro. Whether or not such coupling exists in vivo has been a matter of considerable debate. This paper reviews the development of experimental insight and conceptual views on this topic, describes evidence in favour of and against the presence of such coupling in native myocardium, and identifies directions for further study needed to resolve the riddle, perhaps less so in terms of principal presence which has been demonstrated, but undoubtedly in terms of extent, regulation, patho-physiological context, and actual relevance of cardiac myocyte–non-myocyte coupling in vivo. This article is part of a Special Issue entitled "Myocyte-Fibroblast Signalling in Myocardium." [Copyright &y& Elsevier]

Abstract: In the papers of Nakaoka, he introduced the notion of hearts of (twin) cotorsion pairs on triangulated categories and showed that they have structures of (semi-) abelian categories. We study in this article a twin cotorsion pair , on an exact category with enough projectives and injectives and introduce a notion of the heart. First we show that its heart is preabelian. Moreover we show the heart of a single cotorsion pair is abelian. These results are analog of Nakaokaʼs results in triangulated categories. We also consider special cases where the heart has nicer structure. By our results, the heart of a special twin cotorsion pair , , is integral and almost abelian. Finally we show that the Gabriel–Zisman localization of the heart at the class of regular morphisms is abelian, and moreover it is equivalent to the category of finitely presented modules over a stable subcategory of . [Copyright &y& Elsevier]

Abstract: Fibronectin and its major receptor, integrin α5β1 are required for embryogenesis. These mutants have similar phenotypes, although, defects in integrin α5-deficient mice are milder. In this paper, we examined heart development in those mutants, in which the heart is formed, and discovered that both fibronectin and integrin α5 were required for cardiac morphogenesis, and in particular, for the formation of the cardiac outflow tract. We found that Isl1+ precursors are specified and migrate into the heart in fibronectin- or integrin α5-mutant embryos, however, the hearts in these mutants are of aberrant shape, and the cardiac outflow tracts are short and malformed. We show that these defects are likely due to the requirement for cell adhesion to fibronectin for proliferation of myocardial progenitors and for Fgf8 signaling in the pharyngeal region. [Copyright &y& Elsevier]

Abstract: In vivo MRI data can be corrupted by motion. Motion artifacts are particularly troublesome in Diffusion Weighted MRI (DWI), since the MR signal attenuation due to Brownian motion can be much less than the signal loss due to dephasing from other types of complex tissue motion, which can significantly degrade the estimation of self-diffusion coefficients, diffusion tensors, etc. This paper describes a snapshot DWI sequence, which utilizes a novel single-sided bipolar diffusion sensitizing gradient pulse within a spin echo sequence. The proposed method shortens the diffusion time by applying a single refocused bipolar diffusion gradient on one side of a refocusing RF pulse, instead of a set of diffusion sensitizing gradients, separated by a refocusing RF pulse, while reducing the impact of magnetic field inhomogeneity by using a spin echo sequence. A novel MRI phantom that can exhibit a range of complex motions was designed to demonstrate the robustness of the proposed DWI sequence. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to explore the difficulty faced by consumers in complying with health-related dietary guidelines, focusing on those guidelines that consumers find it more/less difficult to meet and the factors driving the ability to make associated dietary changes. Participants reported self-assessed compliance with 12 dietary recommendations predominantly directed at reducing the risk of heart disease. The difficulty of complying with each of the dietary guidelines was measured using a Rasch model, while the determinants of ability to comply with the dietary recommendations as a whole were identified using regression analysis. The more difficult dietary recommendations included limiting consumption of red meats and consuming the recommended daily intake of fruits and vegetables. Attitudinal variables associated with food, nutrition and health, perception of cholesterol risk and a range of socio-demographic variables, including age, gender and education, were significant determinants of person ability to comply with the dietary recommendations. The results show that there are significant differences in the difficulty faced by consumers in complying with particular dietary recommendations, while there is substantial variation in the ability to eat a healthy diet across participants. [Copyright &y& Elsevier]

Abstract: Gating is necessary in cardio-thoracic small-animal imaging because of the physiological motions that are present during scanning. In small-animal computed tomography (CT), gating is mainly performed on a projection base because full scans take much longer than the motion cycle. This paper presents and discusses various gating concepts of small-animal CT, and provides examples of concrete implementation. Since a wide variety of small-animal CT scanner systems exist, scanner systems are discussed with respect to the most suitable gating methods. Furthermore, an overview is given of cardio-thoracic imaging and gating applications. The necessary contrast media are discussed as well as gating limitations. Gating in small-animal imaging requires the acquisition of a gating signal during scanning. This can be done extrinsically (additional hardware, e.g. electrocardiogram) or intrinsically from the projection data itself. The gating signal is used retrospectively during CT reconstruction, or prospectively to trigger parts of the scan. Gating can be performed with respect to the phase or the amplitude of the gating signal, providing different advantages and challenges. Gating methods should be optimized with respect to the diagnostic question, scanner system, animal model, type of narcosis and actual setup. The software-based intrinsic gating approaches increasingly employed give the researcher independence from difficult and expensive hardware changes. [Copyright &y& Elsevier]

Abstract: In [R. Colpi, K.R. Fuller, Tilting objects in abelian categories and quasitilted rings, Trans. Amer. Math. Soc., in press] tilting objects in an arbitrary abelian category are introduced and are shown to yield a version of the classical tilting theorem between and the category of modules over their endomorphism rings. Moreover, it is shown that given any faithful torsion theory in , for a ring R, the corresponding Heart is an abelian category admitting a tilting object which yields a tilting theorem between the Heart and . In this paper we first prove that is a prototype for any abelian category admitting a tilting object which tilts to in . Then we study AB-type properties of the Heart and commutations with direct limits. This allows us to show, for instance, that any abelian category with a tilting object is AB4, and to find necessary and sufficient conditions which guarantee that is a Grothendieck or even a module category. As particular situations, we examine two main cases: when is hereditary cotilting, proving that is Grothendieck and when is tilting, proving that is a module category. [Copyright &y& Elsevier]

Abstract: Although autoantibodies against the α1-adrenergic receptor which had been found in hypertensive patients had agonist-like activity as phenylephrine, the effects of these antibodies on cardiac remodeling have not been known. In this paper, the models with agonist-like activity of antibodies to α1-adrenergic receptor were made by immunized Wistar rats using synthesized peptides of α1A-adrenergic receptor and raised for 1 year, and the excited antibodies against the α1-adrenergic receptor which could elevate the free Ca2+ in isolated adult rat cardiomyocytes had been existed throughout the experiments after immunization. In immunized rats, despite that systolic blood pressure (SBP) had no difference with normal control, the hypertrophy of heart and cardiomyocytes was observed, the collagen deposition in heart interstitium increased, and c-jun expression and matrix metalloproteinase (MMP)-2 mRNA expression and activity in heart had increased. The results suggested that antibodies against the α1-adrenergic receptor could induce cardiac remodeling and maybe play a particular role in hypertension. [Copyright &y& Elsevier]

Mammalian development follows a defined but adjustable program, depending on the plasticity of embryonic cells ‘response to environmental changes. Heat shock proteins (Hsp) are integral part of this developmental program and gene targeting experiments have started to unravel developmental processes, which exhibit specific requirements for Hsps (e.g. Hsp70.2 for spermatogenesis). In the present paper, we will review available data on Hsp function and discuss the roles of heat shock factors (HSF), their major regulators, in mammalian development. [Copyright &y& Elsevier]

• Estrogen is related to vascular and cognitive risks: hypertension, obesity, smoking, diabetes. • Modern estradiol-based hormone therapy benefits vascular and cognitive outcomes. • Estrogen and vascular disease are both involved in the aetiology of neurodegeneration. • Studies that span the disease prodrome are crucial to determine potential therapeutic benefit. After more than a century of research, we have failed to develop a pharmacological prevention or cure for dementia. There are strong indicators that sex hormones influence cognition. In this paper we discuss the role of these hormones at the intersection between vascular disease and dementia, in light of the mounting literature covering the shared risk factors, pathological features alongside the timeline of hormonal change with the evolution of vascular and neurodegenerative disease. Interactive risk factors and the role of inflammation over the duration of disease evolution are highlighted. Our summary tables assessing the impact of estrogen-based hormone therapy on cognition over the past 45 years illustrate the effort expended to determine the ideal age for intervention and the type, dose, administration, and duration of therapy that might improve or protect cognition as well as alleviate menopausal symptoms. As the prevalence of dementia is rising and is higher in women, it is crucial we advance our knowledge from the "inconclusive" position statement on menopausal hormone therapy of the US Preventive Services Task Force. [ABSTRACT FROM AUTHOR]

• We developed a multi-physics model for the cardiac perfusion. • We proposed an algorithm to generate an intramural vascular network. • We propose a splitting algorithm for the numerical solution and perform a stability analysis for the linear case. • We apply this method to a biventricular human heart. In this paper we present a mathematical and numerical model for human cardiac perfusion which accounts for the different length scales of the vessels in the coronary tree. Epicardial vessels are represented with fully three-dimensional (3D) fluid-dynamics, whereas intramural vessels are modeled as a multi-compartment porous medium. The coupling of these models takes place through interface conditions based on the continuity of mass and momentum. Instead, is neglected in this first preliminary model the myocardium deformation. To estimate the physical parameters of the multi-compartment model, a virtual intramural vascular network is generated using a novel algorithm which works in non-convex domains. Modeling epicardial vessels with a 3D model and intramural ones with a porous medium approach makes it possible to apply the proposed strategy to patient-specific heart geometries reconstructed from clinical imaging data. We also address the derivation of numerical solvers for the coupled problem. In particular, we propose a splitting algorithm for the monolithic problem, with the corresponding convergence analysis performed in a simplified linearized case, and a suitable preconditioner for the multi-compartment porous sub-model. Finally, we test the computational framework in a realistic human heart, obtaining results that fall in the physiological range for both pressures and local myocardial flows. [ABSTRACT FROM AUTHOR]