Cultural impact on the harmonisation of Russian Accounting Standards with the International Financial Reporting Standards: A practitioner's perspective

Purpose – The purpose of this paper is to explore cultural impact on the harmonisation of Russian Accounting Standards with International Financial Reporting Standards (IFRS). Design/methodology/approach – A theoretical review established that differences still exist between the two sets of accounting standards. For decades, Russia was a socialist state of planned economy. Accounting was a tool of centralised control, and accountants had a job of gathering information for statistical purposes of the government and tax authorities. This led to the development of a “Soviet culture” mindset. Accountants saw their jobs as following prescribed rules. Accounting is seen by Hofstede as a field in which historically developed practices are more important than laws of nature. It is therefore expected that accounting rules and the way they are applied will vary among different national cultures. Hence, Gray tried to explore how Hofstede's national cultural dimensions may explain international differences in accounting. With respect to past research in this area, Nobes argued that “national accounting traditions are likely to continue into consolidated reporting where scope for this exists within IFRS rules”. Ding et al. investigated the role of a country's culture and legal origin as an explanation for the differences between local Generally Accepted Accounting Principles (GAAP) and IAS as they were in 2001. The study gathered 53 Russian accountants' attitudes towards reporting under harmonised Russian Accounting Standards through semi structured interviews. Findings – The findings supported the theoretical view of a “Soviet culture” which has an impact on harmonisation of Russian Accounting Standards with the IFRS. Russia's high rankings in such cultural dimensions as power distance, uncertainty avoidance and collectivism have contributed to the development of certain preferences among Russian accountants. Those preferences were for statutory control, uniformity, conservatism and secrecy. Further findings indicate that accountants in Russia display reluctance to disclose financial information to the external users. One of the main reasons was found to be fear of disclosing too much information to competitors. Based on these findings, accountants in Russia display clear signs of preference for secrecy as opposed to transparency, as identified by Gray. Originality/value – One of the contributions of this study is to examine current perceptions of Russian accountants towards financial reporting under new harmonised Russian Accounting Standards based on Rozhnova's study

THE CARBON FIBER METHOD FOR MEASUREMENT OF CONTRACTILE PROPERTIES OF ISOLATED CARDIOMYOCYTES

The direct mechanical measurement of the contractility of an isolated cardiac cell can be realized by the method of carbon fibers (CF). In this method, two CFs are attached to the cell. If weakly attached, CFs may slip out of cell surface under stretch of a cell. This resulted in the deficiency of sarcomere stretch as compared to cell stretch. The purpose of this study was to evaluate the imbalance between the cell and sarcomere stretch in isolated ventricular cardiomyocytes

A cis-regulatory element promoting increased transcription at low temperature in cultured ectothermic Drosophila cells

Background Temperature change affects the myriad of concurrent cellular processes in a non-uniform, disruptive manner. While endothermic organisms minimize the challenge of ambient temperature variation by keeping the core body temperature constant, cells of many ectothermic species maintain homeostatic function within a considerable temperature range. The cellular mechanisms enabling temperature acclimation in ectotherms are still poorly understood. At the transcriptional level, the heat shock response has been analyzed extensively. The opposite, the response to sub-optimal temperature, has received lesser attention in particular in animal species. The tissue specificity of transcriptional responses to cool temperature has not been addressed and it is not clear whether a prominent general response occurs. Cis-regulatory elements (CREs), which mediate increased transcription at cool temperature, and responsible transcription factors are largely unknown. Results The ectotherm Drosophila melanogaster with a presumed temperature optimum around 25 °C was used for transcriptomic analyses of effects of temperatures at the lower end of the readily tolerated range (14–29 °C). Comparative analyses with adult flies and cell culture lines indicated a striking degree of cell-type specificity in the transcriptional response to cool. To identify potential cis-regulatory elements (CREs) for transcriptional upregulation at cool temperature, we analyzed temperature effects on DNA accessibility in chromatin of S2R+ cells. Candidate cis-regulatory elements (CREs) were evaluated with a novel reporter assay for accurate assessment of their temperature-dependency. Robust transcriptional upregulation at low temperature could be demonstrated for a fragment from the pastrel gene, which expresses more transcript and protein at reduced temperatures. This CRE is controlled by the JAK/STAT signaling pathway and antagonizing activities of the transcription factors Pointed and Ets97D. Conclusion Beyond a rich data resource for future analyses of transcriptional control within the readily tolerated range of an ectothermic animal, a novel reporter assay permitting quantitative characterization of CRE temperature dependence was developed. Our identification and functional dissection of the pst_E1 enhancer demonstrate the utility of resources and assay. The functional characterization of this CoolUp enhancer provides initial mechanistic insights into transcriptional upregulation induced by a shift to temperatures at the lower end of the readily tolerated range

MicroRNA-21 is Induced by Rapamycin in a Model of Tuberous Sclerosis (TSC) and Lymphangioleiomyomatosis (LAM)

Lymphangioleiomyomatosis (LAM), a multisystem disease of women, is manifest by the proliferation of smooth muscle-like cells in the lung resulting in cystic lung destruction. Women with LAM can also develop renal angiomyolipomas. LAM is caused by mutations in the tuberous sclerosis complex genes (TSC1 or TSC2), resulting in hyperactive mammalian Target of Rapamycin (mTOR) signaling. The mTOR inhibitor, Rapamycin, stabilizes lung function in LAM and decreases the volume of renal angiomyolipomas, but lung function declines and angiomyolipomas regrow when treatment is discontinued, suggesting that factors induced by mTORC1 inhibition may promote the survival of TSC2-deficient cells. Whether microRNA (miRNA, miR) signaling is involved in the response of LAM to mTORC1 inhibition is unknown. We identified Rapamycin-dependent miRNA in LAM patient angiomyolipoma-derived cells using two separate screens. First, we assayed 132 miRNA of known significance to tumor biology. Using a cut-off of >1.5-fold change, 48 microRNA were Rapamycin-induced, while 4 miRs were downregulated. In a second screen encompassing 946 miRNA, 18 miRs were upregulated by Rapamycin, while eight were downregulated. Dysregulation of miRs 29b, 21, 24, 221, 106a and 199a were common to both platforms and were classified as candidate “RapamiRs.” Validation by qRT-PCR confirmed that these microRNA were increased. miR-21, a pro-survival miR, was the most significantly increased by mTOR-inhibition (p<0.01). The regulation of miR-21 by Rapamycin is cell type independent. mTOR inhibition promotes the processing of the miR-21 transcript (pri-miR-21) to a premature form (pre-miR-21). In conclusion, our findings demonstrate that Rapamycin upregulates multiple miRs, including pro-survival miRs, in TSC2-deficient patient-derived cells. The induction of miRs may contribute to the response of LAM and TSC patients to Rapamycin therapy

A NEW CARBON FIBER METHOD FOR MEASUREMENTS OF CONTRACTILE PROPERTIES OF SINGLE CARDIOMYOCYTES

Investigation of the effects of mechanical load on the contractile function of single cardiomyocytes requires the use of new methods to fix the cardiomyocyte. The technique for measuring the mechanical activity of isolated cells using four carbon fibers is used in this study. This method allows one to obtain new experimental data on the effects of mechanical preload applied via diastolic cell stretch on the contractile function of cardiomyocytes.Работа поддержана Постановлением Правительства РФ № 211 от 16.03.2013 и Программой Президиума РАН №27

Generative Adversarial Networks for Construction of Virtual Populations of Mechanistic Models: Simulations to Study Omecamtiv Mecarbil Action

Biophysical models are increasingly used to gain mechanistic insights by fitting and reproducing experimental and clinical data. The inherent variability in the recorded datasets, however, presents a key challenge. In this study, we present a novel approach, which integrates mechanistic modeling and machine learning to analyze in vitro cardiac mechanics data and solve the inverse problem of model parameter inference. We designed a novel generative adversarial network (GAN) and employed it to construct virtual populations of cardiac ventricular myocyte models in order to study the action of Omecamtiv Mecarbil (OM), a positive cardiac inotrope. Populations of models were calibrated from mechanically unloaded myocyte shortening recordings obtained in experiments on rat myocytes in the presence and absence of OM. The GAN was able to infer model parameters while incorporating prior information about which model parameters OM targets. The generated populations of models reproduced variations in myocyte contraction recorded during in vitro experiments and provided improved understanding of OM’s mechanism of action. Inverse mapping of the experimental data using our approach suggests a novel action of OM, whereby it modifies interactions between myosin and tropomyosin proteins. To validate our approach, the inferred model parameters were used to replicate other in vitro experimental protocols, such as skinned preparations demonstrating an increase in calcium sensitivity and a decrease in the Hill coefficient of the force–calcium (F–Ca) curve under OM action. Our approach thereby facilitated the identification of the mechanistic underpinnings of experimental observations and the exploration of different hypotheses regarding variability in this complex biological system. © 2021, The Author(s).This work was partially supported by the EU’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie (g.a. 764738) state Program (No. AAAA-A19-119070190064-4) and the research grant from RFBR (No. 19-31-90089)

A combined Langendorff-injection technique for simultaneous isolation of single cardiomyocytes from atria and ventricles of the rat heart

Single cardiomyocytes are widely used for investigations of the cellular and molecular mechanisms of regulation and modulation of cardiac performance. Intact cardiomyocytes allow one to study in detail cell function avoiding the effects of extracellular matrix and neighboring cells. The most established protocols of cardiomyocyte isolation are based on the isolated heart perfusion using a Langendorff-apparatus or on intraventricular perfusion using a syringe. However, the yield of single cardiomyocytes obtained by these methods may be low due to the cell injury following non-uniform enzyme digestion of connective tissue in different heart chambers. Moreover, isolation of atrial cardiomyocytes is challenging because of their small size and complex geometric shape. Here we present a new protocol for simultaneous isolation of high quality cardiomyocytes from the atria, ventricular free walls and interventricular septum. The protocol is based on the combination of the Langendorff perfusion method with the intraventricular and intra-atrial injection technique taking into account the collagen content variation between the different heart chambers. Obtained cells demonstrate rod-shaped morphology, a clear and regular sarcomere striation pattern and rat-specific frequency-dependence of contraction and calcium transient parameters. Our protocol provides gentle cell isolation that increases the yield of single cardiomyocytes suitable for biophysical researches. © 2020 The AuthorsSupported by President Grant of the RF #МК-949.2019.4, Russian Foundation for Basic Research # 20-315-70006, and the theme of the IIF UrB RAS #AAAA-A19-119070190064-4

Analysis of Mechanical Alternans in Single Cardiomyocytes in Atrial Fibrillation

Atrial fibrillation (AF) has a significant impact on the contractile function of the heart in the form of alternans activity in atrial cardiomyocytes. In this study, we designed a method for evaluating mechanical alternans in atrial cardiomyocytes in AF.Работа выполнена при поддержке государственной темы ИИФ УрО РАН № 122022200089-4

DEVELOPMENT OF METHOD FOR ANALYSIS OF THE T-TUBULAR SYSTEM IN RAT CARDIOMYOCYTES

The t-system is the highly structured network of membrane invaginations playing an im-portant role in the regulation of cardiac electromechanical coupling and contraction. We de-signed an approach to evaluate the structure of the cardiomyocyte t-tubular system in detail.При поддержке гос.задания ИИФ УрО РАН (тема № AAAA-A19-119070190064-4)

Type 1 Diabetes Impairs Cardiomyocyte Contractility in the Left and Right Ventricular Free Walls but Preserves It in the Interventricular Septum

Type 1 diabetes (T1D) leads to ischemic heart disease and diabetic cardiomyopathy. We tested the hypothesis that T1D differently affects the contractile function of the left and right ventricular free walls (LV, RV) and the interventricular septum (IS) using a rat model of alloxan-induced T1D. Single-myocyte mechanics and cytosolic Ca2+ concentration transients were studied on cardiomyocytes (CM) from LV, RV, and IS in the absence and presence of mechanical load. In addition, we analyzed the phosphorylation level of sarcomeric proteins and the characteristics of the actin-myosin interaction. T1D similarly affected the characteristics of actin-myosin interaction in all studied regions, decreasing the sliding velocity of native thin filaments over myosin in an in vitro motility assay and its Ca2+ sensitivity. A decrease in the thin-filament velocity was associated with increased expression of β-myosin heavy-chain isoform. However, changes in the mechanical function of single ventricular CM induced by T1D were different. T1D depressed the contractility of CM from LV and RV; it decreased the auxotonic tension amplitude and the slope of the active tension-length relationship. Nevertheless, the contractile function of CM from IS was principally preserved. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Funding: This work was supported by the Russian Science Foundation № 18-74-10059. The work was performed using the equipment of the Shared Research Center of Scientific Equipment of Institute of Immunology and Physiology