230 research outputs found

    Jewish Autobiographical Writing. Memoirs of Moses Vasertsug (c. 1760–1832)

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    The article discusses the memoirs of Moses Vasertsug (c. 1760–1832) – an extremely interesting historical source, brilliantly demonstrating processes and phenomena in Jewish society at the turn of the eighteenth and nineteenth centuries. Vasertsug received a traditional religious education and performed related functions in Jewish communities, first in Pomerania (Karlino, Gryfino), and later in Greater Poland (Kórnik) and Mazovia (Płock). He continued to do so in the post-partition period, but the functions he performed took on a new, quasi-official character. The memoirs show the transformation of the previous occupations performed by the Jews, as well as the new opportunities for settlement and economic activity that opened up for them during the post-partition period. The memoirs also show that Jewish autobiographical writing is not necessarily the result of acculturation and departure from Jewish tradition

    Alternative interpretations of grain-size data from Quaternary deposits

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    Several possibilities to present and to interpret the results of granulometric analyses of Quaternary fluvial, aeolian, glacial and wash-out slope deposits were investigated. Attention is paid particularly to the cumulative curves at a probability scale and the frequency curves, and it is shown how these curves can help to determine the sedimentary environment. The inclination of the cumulative curves in the part of the maximum proportion of a particular grain size appears significant. It appears possible to obtain information on the density and dynamics of the transporting medium from the course of the cumulative curves (inclination and spread of grain size). The examination of textural parameters allows to draw regression lines characteristic of both deposits from various sedimentary environments and deposits from one single environment but with different histories as to their transport dynamics

    Extracellular citrate and metabolic adaptations of cancer cells

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    It is well established that cancer cells acquire energy via the Warburg effect and oxidative phosphorylation. Citrate is considered to play a crucial role in cancer metabolism by virtue of its production in the reverse Krebs cycle from glutamine. Here, we review the evidence that extracellular citrate is one of the key metabolites of the metabolic pathways present in cancer cells. We review the different mechanisms by which pathways involved in keeping redox balance respond to the need of intracellular citrate synthesis under different extracellular metabolic conditions. In this context, we further discuss the hypothesis that extracellular citrate plays a role in switching between oxidative phosphorylation and the Warburg effect while citrate uptake enhances metastatic activities and therapy resistance. We also present the possibility that organs rich in citrate such as the liver, brain and bones might form a perfect niche for the secondary tumour growth and improve survival of colonising cancer cells. Consistently, metabolic support provided by cancer-associated and senescent cells is also discussed. Finally, we highlight evidence on the role of citrate on immune cells and its potential to modulate the biological functions of pro- and anti-tumour immune cells in the tumour microenvironment. Collectively, we review intriguing evidence supporting the potential role of extracellular citrate in the regulation of the overall cancer metabolism and metastatic activity

    Dyskeratosis Congenita links telomere attrition to age-related systemic energetics.

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    Underlying mechanisms of plasma metabolite signatures of human ageing and age-related diseases are not clear but telomere attrition and dysfunction are central to both. Dyskeratosis Congenita (DC) is associated with mutations in the telomerase enzyme complex (TERT, TERC, and DKC1) and progressive telomere attrition. We analyzed the effect of telomere attrition on senescence associated metabolites in fibroblast conditioned media and DC patient plasma. Samples were analyzed by gas chromatography/ mass spectrometry and liquid chromatography/ mass spectrometry. We showed extracellular citrate was repressed by canonical telomerase function in vitro and associated with DC leukocyte telomere attrition in vivo; leading to the hypothesis that altered citrate metabolism detects telomere dysfunction. However, elevated citrate and senescence factors only weakly distinguished DC patients from controls, whereas elevated levels of other tricarboxylic acid cycle metabolites, lactate and especially pyruvate distinguished them with high significance. The DC plasma signature most resembled that of patients with loss of function pyruvate dehydrogenase complex mutations and that of older subjects but significantly not those of type 2 diabetes, lactic acidosis, or elevated mitochondrial reactive oxygen species (1-3). Additionally, our data are consistent with further metabolism of citrate and lactate in the liver and kidneys. Citrate uptake in certain organs modulates age-related disease in mice and our data has similarities with age-related disease signatures in humans. Our results have implications for the role of telomere dysfunction in human ageing in addition to its early diagnosis and the monitoring of anti-senescence therapeutics, especially those designed to improve telomere function

    Quartz grain features in modern glacial and proglacial environments : A microscopic study from the Russell Glacier, southwest Greenland

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    Funding Information: and Karol Tylmann, are appreciated. Research was supported by the SIA SunGIS (Edyta Kalińska-Nartiša), by the Post-doctoral Research Project No. 1.1.1.2/VIAA/1/16/118 Comparision of subglacial and ice-marginal formations and processes at the outer zone of the south sector of the Scandinavian Ice Sheet and at the contemporary glaciers in Greenland, Iceland and Antarctica (Kristaps Lamsters) and by the University of Latvia project Climate change and sustainable use of natural resources No. AAP2016/B041. We thank Reinis Pāvils for field assistance. Publisher Copyright: © 2017 Polish Academy of Sciences.It is assumed that close to the margins of ice-sheets, glacial, fluvial and aeolian processes overlap, and combined with weathering processes, produce numerous sediments, in which quartz is a common mineral. Quartz grains, if available, may serve as a powerful tool in determining the depositional history, transportation mode and postdepositional processes. However, quartz grain studies in some modern glacial areas are still sparse. In this study, we examine for the first time quartz grains sampled from the modern glacial and proglacial environments of the Russell Glacier, southwest Greenland in binocular microscope and scanning electron microscope, to analyze their shape, character of surface and microtextures. We debate whether the investigated quartz grains reveal glacial characteristics and to what extent they carry a signal of another transportation and sedimentary processes. Although glacial fracturing and abrasion occur in grain suites, most mechanical origin features are not of a high frequency or freshness, potentially suggesting a reduced shear stress in the glacier from its limited thickness and influence of the pressurized water at the ice-bed. In contrast, the signal that originates from the fluvial environment is much stronger derived by numerous aqueous-induced features present on quartz grain surfaces. Aeolian-induced microtextures on grain surfaces increase among the samples the closest to the ice margin, which may be due to enhanced aeolian activity, but are practically absent in sediments taken from the small scale aeolian landforms. In contrast, aeolian grains have been found in the bigger-size (1.0-2.0 mm) investigated fraction. These grains gained the strongest aeolian abrasion, possibly due to changes in transportation mode.publishersversionPeer reviewe

    Expression of the plasma membrane citrate carrier (pmCiC) in human cancerous tissues—correlation with tumour aggressiveness

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    We have recently shown that cancer cells of various origins take up extracellular citrate through the plasma membrane citrate carrier (pmCiC), a specific plasma membrane citrate transporter. Extracellular citrate is required to support cancer cell metabolism, in particular fatty acid synthesis, mitochondrial activity, protein synthesis and histone acetylation. In addition, cancer cells tend to acquire a metastatic phenotype in the presence of extracellular citrate. Our recent study also showed that cancer-associated stromal cells synthesise and release citrate and that this process is controlled by cancer cells. In the present study, we evaluated the expression of pmCiC, fibroblast activation protein-α (FAP) and the angiogenesis marker cluster of differentiation 31 (CD31) in human cancer tissues of different origins. In the cohort studied, we found no correlation between disease stage and the expression of FAP or CD31. However, we have identified a clear correlation between pmCiC expression in cancer cells and cancer-associated stroma with tumour stage. It can be concluded that pmCiC is increased in cancer cells and in cancer-supporting cells in the tumour microenvironment at the later stages of cancer development, particularly at the metastatic sites. Therefore, pmCiC expression has the potential to serve as a prognostic marker, although further studies are needed

    Neuronal characteristics of small-cell lung cancer

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    Wide ranging experimental evidence suggests that human small-cell lung cancer (SCLC) has a number of molecular and subcellular characteristics normally associated with neurones. This review outlines and discusses these characteristics in the light of recent developments in the field. Emphasis is placed upon neuronal cell adhesion molecules, neurone-restrictive silencer factor, neurotransmitters/peptides and voltage-gated ion, especially Na+ channels. The hypothesis is put forward that acquisition of such characteristics and the membrane ‘excitability' that would follow can accelerate metastatic progression. The clinical potential of the neuronal characteristics of SCLC, in particular ion channel expression/activity, is discussed in relation to possible novel diagnostic and therapeutic modalities

    Hsp90 Inhibition Affects Cell Metabolism by Disrupting Mitochondrial Protein Insertion

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    Hsp90 is a molecular chaperone interacting with hundreds client proteins. Little is known, however, about Hsp90 influence on cancer cell metabolism. Here we show that the inhibition of Hsp90 affects indirectly glycolysis by disrupting mitochondrial insertion of the elements of Translocase of the Outer Membrane (TOM) complex in tumor cells. Improper insertion of Tom40 decreases the abundance of many mitochondrial proteins resulting in reduced mitochondrial activity. This is accompanied by increased production and release of lactate and serine. These results indicate an increased rate of glycolysis with serine synthesis compensating for the loss of energy and mitochondrially derived metabolites, potentially enhancing the metastatic potential of surviving cells. Our results provide novel insights into the effects of Hsp90 inhibition on cancer cell metabolism
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