Discourse as the basis of pragmatic analysis

The article deals with the problems of discourse definition and its types. The authors analyse different views which concern the including of the term “dialogue” into “discourse” along with “monologue”. Special attention is paid to the description of a literary dialogue having its own features and special interest for pragmatic analysis as almost all utterances are performativeyesBelgorod State Universit

Reflection of the status and role of social structure in agentive impersonal sentences in german

The article is devoted to the implicit representation of status and role groups in society on the material of impersonal sentences in the german language. The focus is set on the types of the implicit semantic subject, characterized by varying degrees of determination in context: indefinite-personal, generalizedpersonal and definite-personal semantic subject. The authors propose a tripartite paradigm of types of the implicit semantic subject on the basis of its social and role affiliatio

Перфузионная компьютерная томография в диагностике заболеваний почек (обзор литературы)

Purpose. To analyze the literature data on the use of CT perfusion in kidney diseases and to assess the future prospects of using the technique in clinical practice.Materials and methods. In electronic databases (PubMed, E-library, Web of Science, Google Scholar), a search was conducted for published studies evaluating the possibilities of using CT perfusion in both neoplastic and non-neoplastic kidney diseases. The article analyzes the results of 40 most relevant works of Russian and foreign researchers devoted to this topic.Results. According to the analysis of the data obtained, perfusion CT is an effective diagnostic tool in oncology: the technique allows noninvasively assessing the nature of the tumour, including differentiating benign nodes (fat-poor angiomyolipoma and oncocytoma) from renal cell carcinoma; to establish the histological variant of renal cell carcinoma and Fuhrman grade, to characterize the effectiveness of ablative techniques and systemic treatment of renal cell carcinoma. Based on the correlation of CT kidney perfusion data and the results of various methods for determining organ function, the possibility of using perfusion CT as one of the prognostic factors for determining the tactics of treatment of patients with obstructive uropathies, aortomesenteric compression, and also shows the potential of using the technique in transplantology both in patients after surgery and during the examination of donors.Conclusions. Despite the fact that the role of CT kidney perfusion in various fields of urology and nephrology has been sufficiently studied, some important aspects of the likely application of this technique remain underestimated. Taking into account the high incidence rates and a significant percentage of localized forms of tumors, the study of the role of CT perfusion in planning and evaluating the results of nephron-sparing treatment of renal cell carcinoma may open up new prospects in optimizing surgical tactics.Цель исследования: провести анализ литературных данных по использованию КТ-перфузии при заболеваниях почек и оценить дальнейшие перспективы применения методики в клинической практике.Материал и методы. В электронных базах данных (PubMed, E-library, Web of Science, Google Scholar) был проведен поиск опубликованных исследований, оценивающих возможности применения КТ-перфузии при заболеваниях почек как неопластического, так и неопухолевого характера. В статье проанализированы результаты 40 наиболее релевантных работ российских и зарубежных исследователей, посвященных этой тематике.Результаты. Согласно анализу полученных данных, перфузионная КТ является эффективным диагностическим инструментом в онкологии: методика позволяет неинвазивно оценить характер новообразования, в том числе дифференцировать доброкачественные узлы (ангиомиолипому с низким содержанием жира и онкоцитому) от рака почки, установить гистологический вариант почечно-клеточного рака и степень злокачественности опухоли по Fuhrman, охарактеризовать эффективность аблативных методик и системного лечения рака почки. Базируясь на корреляции данных КТ-перфузии почек и результатов различных методов определения функции органа, доказана возможность применения перфузионной КТ в качестве одного из прогностических факторов для определения тактики лечения больных с обструктивными уропатиями, аортомезентериальной компрессией, а также показан потенциал использования методики в трансплантологии как у пациентов после проведенной операции, так и при обследовании доноров.Заключение. Несмотря на то что роль КТ-перфузии почек в различных областях урологии и нефрологии достаточно изучена, некоторые важные аспекты вероятного применения этой методики остаются недооцененными. С учетом высоких показателей заболеваемости и значимого процента локализованных форм опухолей изучение роли КТ-перфузии в планировании и оценке результатов органосохраняющего лечения рака почки может открыть новые перспективы в оптимизации хирургической тактики

Phosphorylation of Puma modulates its apoptotic function by regulating protein stability

Puma is a potent BH3-only protein that antagonises anti-apoptotic Bcl-2 proteins, promotes Bax/Bak activation and has an essential role in multiple apoptotic models. Puma expression is normally kept very low, but can be induced by several transcription factors including p53, p73, E2F1 and FOXO3a, whereby it can induce an apoptotic response. As Puma can to bind and inactivate all anti-apoptotic members of the Bcl-2 family, its activity must be tightly controlled. We report here, for the first time, evidence that Puma is subject to post-translational control through phosphorylation. We show that Puma is phosphorylated at multiple sites, with the major site of phosphorylation being serine 10. Replacing serine 10 with alanine causes reduced Puma turnover and enhanced cell death. Interestingly, Puma turnover occurs through the proteasome, and substitution of serine 10 causes elevated Puma levels independently of macroautophagy, Bcl-2 family member binding, caspase activity and apoptotic death. We conclude, therefore, that phosphorylation of Puma at serine 10 promotes Puma turnover, represses Puma's cell death potential and promotes cell survival. Owing to the highly pro-apoptotic nature of Puma, these studies highlight an important additional regulatory step in the determination of cellular life or death

Intrinsic Order and Disorder in the Bcl-2 Member Harakiri: Insights into Its Proapoptotic Activity

Harakiri is a BH3-only member of the Bcl-2 family that localizes in membranes and induces cell death by binding to prosurvival Bcl-xL and Bcl-2. The cytosolic domain of Harakiri is largely disorder with residual α-helical conformation according to previous structural studies. As these helical structures could play an important role in Harakiri's function, we have used NMR and circular dichroism to fully characterize them at the residue-atomic level. In addition, we report structural studies on a peptide fragment spanning Harakiri's C-terminal hydrophobic sequence, which potentially operates as a transmembrane domain. We initially checked by enzyme immunoassays and NMR that peptides encompassing different lengths of the cytosolic domain are functional as they bind Bcl-xL and Bcl-2. The structural data in water indicate that the α-helical conformation is restricted to a 25-residue segment comprising the BH3 domain. However, structure calculation was precluded because of insufficient NMR restraints. To bypass this problem we used alcohol-water mixture to increase structure population and confirmed by NMR that the conformation in both milieus is equivalent. The resulting three-dimensional structure closely resembles that of peptides encompassing the BH3 domain of BH3-only members in complex with their prosurvival partners, suggesting that preformed structural elements in the disordered protein are central to binding. In contrast, the transmembrane domain forms in micelles a monomeric α-helix with a population close to 100%. Its three-dimensional structure here reported reveals features that explain its function as membrane anchor. Altogether these results are used to propose a tentative structural model of how Harakiri works

Mutual Regulation of Bcl-2 Proteins Independent of the BH3 Domain as Shown by the BH3-Lacking Protein Bcl-xAK

The BH3 domain of Bcl-2 proteins was regarded as indispensable for apoptosis induction and for mutual regulation of family members. We recently described Bcl-xAK, a proapoptotic splice product of the bcl-x gene, which lacks BH3 but encloses BH2, BH4 and a transmembrane domain. It remained however unclear, how Bcl-xAK may trigger apoptosis

Intrinsic Order and Disorder in the Bcl-2 Member Harakiri: Insights into Its Proapoptotic Activity

Harakiri is a BH3-only member of the Bcl-2 family that localizes in membranes and induces cell death by binding to prosurvival Bcl-xL and Bcl-2. The cytosolic domain of Harakiri is largely disorder with residual α-helical conformation according to previous structural studies. As these helical structures could play an important role in Harakiri's function, we have used NMR and circular dichroism to fully characterize them at the residue-atomic level. In addition, we report structural studies on a peptide fragment spanning Harakiri's C-terminal hydrophobic sequence, which potentially operates as a transmembrane domain. We initially checked by enzyme immunoassays and NMR that peptides encompassing different lengths of the cytosolic domain are functional as they bind Bcl-xL and Bcl-2. The structural data in water indicate that the α-helical conformation is restricted to a 25-residue segment comprising the BH3 domain. However, structure calculation was precluded because of insufficient NMR restraints. To bypass this problem we used alcohol-water mixture to increase structure population and confirmed by NMR that the conformation in both milieus is equivalent. The resulting three-dimensional structure closely resembles that of peptides encompassing the BH3 domain of BH3-only members in complex with their prosurvival partners, suggesting that preformed structural elements in the disordered protein are central to binding. In contrast, the transmembrane domain forms in micelles a monomeric α-helix with a population close to 100%. Its three-dimensional structure here reported reveals features that explain its function as membrane anchor. Altogether these results are used to propose a tentative structural model of how Harakiri works

Characterization of a Novel Interaction between Bcl-2 Members Diva and Harakiri

Interactions within proteins of the Bcl-2 family are key in the regulation of apoptosis. The death-inducing members control apoptotic mechanisms partly by antagonizing the prosurvival proteins through heterodimer formation. Structural and biophysical studies on these complexes are providing important clues to understand their function. To help improve our knowledge on protein-protein interactions within the Bcl-2 family we have studied the binding between two of its members: mouse Diva and human Harakiri. Diva has been shown to perform both prosurvival and killing activity. In contrast, Harakiri induces cell death by interacting with antiapoptotic Bcl-2 members. Here we show using ELISA and NMR that Diva and Harakiri can interact in vitro. Combining the NMR data with the previously reported three-dimensional structure of Diva we find that Harakiri binds to a specific region in Diva. This interacting surface is equivalent to the known binding area of prosurvival Bcl-2 members from the reported structures of the complexes, suggesting that Diva could function at the structural level similarly to the antiapoptotic proteins of the Bcl-2 family. We illustrate this result by building a structural model of the heterodimer using molecular docking and the NMR data as restraints. Moreover, combining circular dichroism and NMR we also show that Harakiri is largely unstructured with residual (13%) α-helical conformation. This result agrees with intrinsic disorder previously observed in other Bcl-2 members. In addition, Harakiri constructs of different length were studied to identify the region critical for the interaction. Differential affinity for Diva of these constructs suggests that the amino acid sequence flanking the interacting region could play an important role in binding

HCV genome-wide genetic analyses in context of disease progression and hepatocellular carcinoma

<div><p>Hepatitis C virus (HCV) is a major cause of hepatitis and hepatocellular carcinoma (HCC) world-wide. Most HCV patients have relatively stable disease, but approximately 25% have progressive disease that often terminates in liver failure or HCC. HCV is highly variable genetically, with seven genotypes and multiple subtypes per genotype. This variation affects HCV’s sensitivity to antiviral therapy and has been implicated to contribute to differences in disease. We sequenced the complete viral coding capacity for 107 HCV genotype 1 isolates to determine whether genetic variation between independent HCV isolates is associated with the rate of disease progression or development of HCC. Consensus sequences were determined by sequencing RT-PCR products from serum or plasma. Positions of amino acid conservation, amino acid diversity patterns, selection pressures, and genome-wide patterns of amino acid covariance were assessed in context of the clinical phenotypes. A few positions were found where the amino acid distributions or degree of positive selection differed between in the HCC and cirrhotic sequences. All other assessments of viral genetic variation and HCC failed to yield significant associations. Sequences from patients with slow disease progression were under a greater degree of positive selection than sequences from rapid progressors, but all other analyses comparing HCV from rapid and slow disease progressors were statistically insignificant. The failure to observe distinct sequence differences associated with disease progression or HCC employing methods that previously revealed strong associations with the outcome of interferon α-based therapy implies that variable ability of HCV to modulate interferon responses is not a dominant cause for differential pathology among HCV patients. This lack of significant associations also implies that host and/or environmental factors are the major causes of differential disease presentation in HCV patients.</p></div