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The article discusses the features of monitoring the dynamic impact, processes of vibration driving and vibro-extraction of sheet piles in conditions of a large thickness of weak, water-saturated soils. Many years of development experience has shown that, with respect to reliability, it is not enough to carry out analysis with calculations only in the preparation of loadings. The generated vibration field has a negative impact on the structures located near. The analysis of the existing normative documents on the assessment of the dynamic impact on the construction site is given. It is noted that modern monitoring techniques make it possible to assess the impact of the surface Rayleigh wave, however, the development of additional deformations of buildings is caused by deep, body waves that affect the weak underlying soils of the base. Based on the results of numerical modeling and analysis of experimental studies of other authors, an alternative scheme for installing vibration sensors is proposed for assessing the dynamic impact during immersion and extraction of sheet piles.

The article considers the issues of geotechnical substantiation and application of constructive and technological measures for the construction of underground space up to 4.4 m deep in the closed courtyard of the Palace built in the 18th century in conditions of weak water-saturated soils in the historical center of St. Petersburg. The underground space of 18.4 x 29.4 m was arranged in close proximity to the enclosing structures of civil buildings built in the 18th - 19th centuries. The article presents design solutions based on the finite element calculation method for strengthening the foundations of existing buildings, enclosing the pit and the foundations of the new structures, which comprehensively ensure compliance with the required safe additional deformations of the surrounding buildings. The results of geotechnical monitoring are presented in comparison with the results of a numerical calculation of the main load-bearing structures of new and existing buildings of the surrounding development during the construction process.

(1) Pulmonary hypertension (PH)-associated right ventricular (RV) failure is linked to a reduction in pulmonary vasodilators. Treprostinil has shown effectiveness in PAH patients with cardiac decompensation, hinting at potential cardiac benefits. We investigated treprostinil's synergy with isoprenaline in RV and LV cardiomyocytes. We hypothesised that disease-related RV structural changes in cardiomyocytes would reduce contractile responses and cAMP/PKA signalling activity. (2) We induced PH in male Sprague Dawley rats using monocrotaline and isolated their ventricular cardiomyocytes. The effect of in vitro treprostinil and isoprenaline stimulation on contraction was assessed. FRET microscopy was used to study PKA activity associated with treprostinil stimulation in AKAR3-NES FRET-based biosensor-expressing cells. (3) RV cells exhibited maladaptive remodelling with hypertrophy, impaired contractility, and calcium transients compared to control and LV cardiomyocytes. Combining treprostinil and isoprenaline failed to enhance inotropy in PH RV cardiomyocytes. PH RV cardiomyocytes displayed an aberrant contractile behaviour, which the combination treatment could not rectify. Finally, we observed decreased PKA activity in treprostinil-treated PH RV cardiomyocytes. (4) PH-associated RV cardiomyocyte remodelling reduced treprostinil sensitivity, inotropic support, and impaired relaxation. Overall, this study highlights the complexity of RV dysfunction in advanced PH and suggests the need for alternative therapeutic strategies. [ABSTRACT FROM AUTHOR]

Cardiomyocytes from the apex but not the base of the heart increase their contractility in response to β2-adrenoceptor (β2AR) stimulation, which may underlie the development of Takotsubo cardiomyopathy. However, both cell types produce comparable cytosolic amounts of the second messenger cAMP. We investigated this discrepancy using nanoscale imaging techniques and found that, structurally, basal cardiomyocytes have more organized membranes (higher T-tubular and caveolar densities). Local membrane microdomain responses measured in isolated basal cardiomyocytes or in whole hearts revealed significantly smaller and more short-lived β2AR/cAMP signals. Inhibition of PDE4, caveolar disruption by removing cholesterol or genetic deletion of Cav3 eliminated differences in local cAMP production and equilibrated the contractile response toAR. We conclude that basal cells possess tighter control of cAMP because of a higher degree of signaling microdomain organization. This provides varying levels of nanostructural control for cAMPmediated functional effects that orchestrate macroscopic, regional physiological differences within the heart. [ABSTRACT FROM AUTHOR]

Abstract: Plasma apolipoprotein E (apoE) is a 34-kDa polymorphic protein which has atheroprotective actions by clearing remnant lipoproteins and sequestering excess cellular cholesterol. Low or dysfunctional apoE is a risk factor for hyperlipidaemia and atherosclerosis, and for restenosis after angioplasty. Here, in short-term studies designed to establish proof-of-principle, we investigate whether encapsulated recombinant Chinese hamster ovary (CHO) cells can secrete wild-type apoE3 protein in vitro and then determine whether peritoneal implantation of the microcapsules into apoE-deficient (apoE−/−) mice reduces their hypercholesterolaemia. Recombinant CHO-E3 cells were encapsulated into either alginate poly-l-lysine or alginate polyethyleneimine/polybrene microspheres. After verifying stability and apoE3 secretion, the beads were then implanted into the peritoneal cavity of apoE−/− mice; levels of plasma apoE3, cholesterol and lipoproteins were monitored for up to 14 days post-implantation. Encapsulated CHO-E3 cells continued to secrete apoE3 protein throughout a 60-day study period in vitro, though levels declined after 14 days. This cell-derived apoE3 was biologically active. When conditioned medium from encapsulated CHO-E3 cells was incubated with cultured cells pre-labelled with [3H]-cholesterol, efflux of cholesterol was two to four times greater than with normal medium (at 8 h, for example, 7.4±0.3% vs. 2.4±0.2% of cellular cholesterol; P<0.001). Moreover, when secreted apoE3 was injected intraperitoneally into apoE−/− mice, apoE3 was detected in plasma and the hyperlipidaemia improved. Similarly, when alginate polyethyleneimine/polybrene capsules were implanted into the peritoneum of apoE−/− mice, apoE3 was secreted into plasma and at 7 days total cholesterol was reduced, while atheroprotective high-density lipoprotein (HDL) increased. In a second study, apoE was detectable in plasma of five mice treated with alginate poly-l-lysine beads, 4 and 7 days post-implantation, though not at day 14. Furthermore, their hypercholesterolaemia was reduced, while HDL was clearly elevated in all mice at days 4 and 7 (from 18.4±6.2% of total lipoproteins to 31.1±6.8% at 7 days; P<0.001); however, these had rebounded by day 14, possibly due to the emergence of anti-apoE antibodies. We conclude that microencapsulated apoE-secreting cells have the potential to ameliorate the hyperlipidaemia of apoE deficiency, but that the technology must be improved to become a feasible therapeutic to treat atherosclerosis. [Copyright &y& Elsevier]

Insulin receptor substrate 2 (Irs2) plays complex roles in energy homeostasis. We generated mice lacking Irs2 in beta cells and a population of hypothalamic neurons (RIPCreIrs2KO), in all neurons (NesCreIrs2KO), and in proopiomelanocortin neurons (POMCCreIrs2KO) to determine the role of Irs2 in the CNS and beta cell. RIPCreIrs2KO mice displayed impaired glucose tolerance and reduced beta cell mass. Overt diabetes did not ensue, because beta cells escaping Cre-mediated recombination progressively populated islets. RIPCreIrs2KO and NesCreIrs2KO mice displayed hyperphagia, obesity, and increased body length, which suggests altered melanocortin action. POMCCreIrs2KO mice did not display this phenotype. RIPCreIrs2KO and NesCreIrs2KO mice retained leptin sensitivity, which suggests that CNS Irs2 pathways are not required for leptin action. NesCreIrs2KO and POMCCreIrs2KO mice did not display reduced beta cell mass, but NesCreIrs2KO mice displayed mild abnormalities of glucose homeostasis. RIPCre neurons did not express POMC or neuropeptide Y. Insulin and a melanocortin agonist depolarized RIPCre neurons, whereas leptin was ineffective. Insulin hyperpolarized and leptin depolarized POMC neurons. Our findings demonstrate a critical role for IRS2 in beta cell and hypothalamic function and provide insights into the role of RIPCre neurons, a distinct hypothalamic neuronal population, in growth and energy homeostasis. [ABSTRACT FROM AUTHOR]

The ability to differentiate induced-pluripotent stem cells into cardiomyocytes (iPSC-CMs) has opened up novel avenues for potential cardiac therapies. However, iPSC-CMs exhibit a range of somewhat immature functional properties. This study explored the development of the beta-adrenergic receptor (βAR) pathway, which is crucial in regulating contraction and signifying the health and maturity of myocytes. We explored the compartmentation of β 2 AR-signalling and phosphodiesterases (PDEs) in caveolae, as functional nanodomains supporting the mature phenotype. Förster Resonance Energy Transfer (FRET) microscopy was used to study the cyclic adenosine monophosphate (cAMP) levels in iPSC-CMs at day 30, 60, and 90 following βAR subtype-specific stimulation. Subsequently, the PDE2, PDE3, and PDE4 activity was investigated using specific inhibitors. Cells were treated with methyl-β-cyclodextrin (MβCD) to remove cholesterol as a method of decompartmentalising β 2 AR. As iPSC-CMs mature with a prolonged culture time, the caveolae density is increased, leading to a reduction in the overall cytoplasmic cAMP signal stimulated through β 2 AR (but not β 1 AR). Pan-phosphodiesterase inhibition or caveolae depletion leads to an increase in the β 2 AR-stimulated cytoplasmic cAMP. Moreover, with time in culture, the increase in the βAR-dependent cytoplasmic cAMP becomes more sensitive to cholesterol removal. The regulation of the β 2 AR response by PDE2 and 4 is similarly increased with the time in culture. We conclude that both the β 2 AR and PDEs are restricted to the caveolae nanodomains, and thereby exhibit a tighter spatial restriction over the cAMP signal in late-stage compared to early iPSC-CMs.

Dynamin 2 (DNM2) is a GTP-binding protein that controls endocytic vesicle scission and defines a whole class of dynamin-dependent endocytosis, including clathrin-mediated endocytosis by caveoli. It has been suggested that mutations in the DNM2 gene, associated with 3 inherited diseases, disrupt endocytosis. However, how exactly mutations affect the nanoscale morphology of endocytic machinery has never been studied. In this paper, we used live correlative scanning ion conductance microscopy (SICM) and fluorescence confocal microscopy (FCM) to study how disease-associated mutations affect the morphology and kinetics of clathrin-coated pits (CCPs) by directly following their dynamics of formation, maturation, and internalization in skin fibroblasts from patients with centronuclear myopathy (CNM) and in Cos-7 cells expressing corresponding dynamin mutants. Using SICM-FCM, which we have developed, we show how p.R465W mutation disrupts pit structure, preventing its maturation and internalization, and significantly increases the lifetime of CCPs. Differently, p.R522H slows down the formation of CCPs without affecting their internalization. We also found that CNM mutations in DNM2 affect the distribution of caveoli and reduce dorsal ruffling in human skin fibroblasts. Collectively, our SICM-FCM findings at single CCP level, backed up by electron microscopy data, argue for the impairment of several forms of endocytosis in DNM2 -linked CNM.-Ali, T., Bednarska, J., Vassilopoulos, S., Tran, M., Diakonov, I. A., Ziyadeh-Isleem, A., Guicheney, P., Gorelik, J., Korchev, Y. E., Reilly, M. M., Bitoun, M., Shevchuk, A. Correlative SICM-FCM reveals changes in morphology and kinetics of endocytic pits induced by disease-associated mutations in dynamin.

Cardiomyocytes from the apex but not the base of the heart increase their contractility in response to β 2 -adrenoceptor (β 2 AR) stimulation, which may underlie the development of Takotsubo cardiomyopathy. However, both cell types produce comparable cytosolic amounts of the second messenger cAMP. We investigated this discrepancy using nanoscale imaging techniques and found that, structurally, basal cardiomyocytes have more organized membranes (higher T-tubular and caveolar densities). Local membrane microdomain responses measured in isolated basal cardiomyocytes or in whole hearts revealed significantly smaller and more short-lived β 2 AR/cAMP signals. Inhibition of PDE4, caveolar disruption by removing cholesterol or genetic deletion of Cav3 eliminated differences in local cAMP production and equilibrated the contractile response to β 2 AR. We conclude that basal cells possess tighter control of cAMP because of a higher degree of signaling microdomain organization. This provides varying levels of nanostructural control for cAMP-mediated functional effects that orchestrate macroscopic, regional physiological differences within the heart., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Takotsubo cardiomyopathy is an acute heart failure syndrome characterized by myocardial hypocontractility from the mid left ventricle to the apex. It is precipitated by extreme stress and can be triggered by intravenous catecholamine administration, particularly epinephrine. Despite its grave presentation, Takotsubo cardiomyopathy is rapidly reversible, with generally good prognosis. We hypothesized that this represents switching of epinephrine signaling through the pleiotropic β(2)-adrenergic receptor (β(2)AR) from canonical stimulatory G-protein-activated cardiostimulant to inhibitory G-protein-activated cardiodepressant pathways., Methods and Results: We describe an in vivo rat model in which a high intravenous epinephrine, but not norepinephrine, bolus produces the characteristic reversible apical depression of myocardial contraction coupled with basal hypercontractility. The effect is prevented via G(i) inactivation by pertussis toxin pretreatment. β(2)AR number and functional responses were greater in isolated apical cardiomyocytes than in basal cardiomyocytes, which confirmed the higher apical sensitivity and response to circulating epinephrine. In vitro studies demonstrated high-dose epinephrine can induce direct cardiomyocyte cardiodepression and cardioprotection in a β(2)AR-Gi-dependent manner. Preventing epinephrine-G(i) effects increased mortality in the Takotsubo model, whereas β-blockers that activate β(2)AR-G(i) exacerbated the epinephrine-dependent negative inotropic effects without further deaths. In contrast, levosimendan rescued the acute cardiac dysfunction without increased mortality., Conclusions: We suggest that biased agonism of epinephrine for β(2)AR-G(s) at low concentrations and for G(i) at high concentrations underpins the acute apical cardiodepression observed in Takotsubo cardiomyopathy, with an apical-basal gradient in β(2)ARs explaining the differential regional responses. We suggest this epinephrine-specific β(2)AR-G(i) signaling may have evolved as a cardioprotective strategy to limit catecholamine-induced myocardial toxicity during acute stress.