Исследование каталитической активности высокодисперсных порошков железа в синтезе Фишера-Тропша

Объектом данного исследования являлся высокодисперсный порошок железа, полученный методом электрического взрыва проводника, с последующим таблетированием под высоким давлением. Целью данной работы являлось изучение каталитической активности железного катализатора в синтезе Фишера-Тропша.The object of study is the superfine iron powder obtained by the method of electrical explosion with subsequent tableting with high pressure. The purpose of the work is to study of the catalytic activity iron catalyst in Fischer-Tropsch synthesi

A Comparison of the Magmatic Evolution of Pacific Intraplate Volcanoes: Constraints on Melting in Mantle Plumes

The interaction of deep mantle plumes with lithospheric plates is one fundamental concept of plate tectonics. Based on observations mainly made on the Hawaiian volcanoes the compositional evolution of hotspot volcanoes is believed to reflect the variation of partial melting and source composition as the plate moves across the different melting zones of the mantle plume. The model predicts the formation of several magmatic stages that differ in composition. In order to test this model, we compare published compositional and age data from the intraplate volcanoes of the Hawaii, Society, Marquesas and Samoa hotspots on the older part of the Pacific Plate. The compiled data indicate that most volcanoes display variations within and between several magmatic series, and in most cases the more evolved lavas are associated with the voluminous shield stage. The Hawaiian volcanoes show up to four different series ranging from tholeiites to nephelinites/melilitites, whereas the other hotspots mainly erupt two magmatic series consisting of transitional basalts and basanites. Submarine preshield stages at the Society and Marquesas hotspots resemble those observed at Hawaii. The large variation of primitive magmas in the Hawaiian plume as opposed to the other Pacific intraplate systems may reflect the higher temperatures, higher buoyancy flux, and extreme chemical heterogeneity at Hawaii. The shield stage activity at all four hotspots lasts for 1 million years indicating similar widths of the melting zone, although the temperatures of the distinct mantle plumes vary considerably. The relatively depleted shield stage magmatism typically overlaps by ~200 kyrs with the formation of the more enriched postshield magmas indicating that the two melting and magma ascent systems exist contemporaneously

Germline landscape of RPA1, RPA2 and RPA3 variants in pediatric malignancies: identification of RPA1 as a novel cancer predisposition candidate gene

Replication Protein A (RPA) is single-strand DNA binding protein that plays a key role in the replication and repair of DNA. RPA is a heterotrimer made of 3 subunits – RPA1, RPA2, and RPA3. Germline pathogenic variants affecting RPA1 were recently described in patients with Telomere Biology Disorders (TBD), also known as dyskeratosis congenita or short telomere syndrome. Premature telomere shortening is a hallmark of TBD and results in bone marrow failure and predisposition to hematologic malignancies. Building on the finding that somatic mutations in RPA subunit genes occur in ~1% of cancers, we hypothesized that germline RPA alterations might be enriched in human cancers. Because germline RPA1 mutations are linked to early onset TBD with predisposition to myelodysplastic syndromes, we interrogated pediatric cancer cohorts to define the prevalence and spectrum of rare/novel and putative damaging germline RPA1, RPA2, and RPA3 variants. In this study of 5,993 children with cancer, 75 (1.25%) harbored heterozygous rare (non-cancer population allele frequency (AF) < 0.1%) variants in the RPA heterotrimer genes, of which 51 cases (0.85%) had ultra-rare (AF < 0.005%) or novel variants. Compared with Genome Aggregation Database (gnomAD) non-cancer controls, there was significant enrichment of ultra-rare and novel RPA1, but not RPA2 or RPA3, germline variants in our cohort (adjusted p-value < 0.05). Taken together, these findings suggest that germline putative damaging variants affecting RPA1 are found in excess in children with cancer, warranting further investigation into the functional role of these variants in oncogenesis

Successful allogeneic stem cell transplantation of a patient with Werner syndrome and acute myeloid leukemia.

peer reviewe

The atypical kinase RIOK1 promotes tumor growth and invasive behavior

Despite being overexpressed in different tumor entities, RIO kinases are hardly characterized in mammalian cells. We investigated the role of these atypical kinases in different cancer cells. Using isogenic colon-, breast- and lung cancer cell lines, we demonstrate that knockdown of RIOK1, but not of RIOK2 or RIOK3, strongly impairs proliferation and invasiveness in conventional and 3D culture systems. Interestingly, these effects were mainly observed in RAS mutant cancer cells. In contrast, growth of RAS wildtype Caco-2 and Bcr-Abl-driven K562 cells is not affected by RIOK1 knockdown, suggesting a specific requirement for RIOK1 in the context of oncogenic RAS signaling. Furthermore, we show that RIOK1 activates NF-κB signaling and promotes cell cycle progression. Using proteomics, we identified the pro-invasive proteins Metadherin and Stathmin1 to be regulated by RIOK1. Additionally, we demonstrate that RIOK1 promotes lung colonization in vivo and that RIOK1 is overexpressed in different subtypes of human lung- and breast cancer. Altogether, our data suggest RIOK1 as a potential therapeutic target, especially in RAS-driven cancers

Salvage HLA-haploidentical hematopoietic stem cell transplantation with post-transplant cyclophosphamide for graft failure in non-malignant disorders

Graft failure requires urgent salvage HSCT, but there is no universally accepted approach for this situation. We investigated T-cell replete haploidentical HSCT with post-transplantation cyclophosphamide following serotherapy-based, radiation-free, reduced intensity conditioning in children with non-malignant disorders who had rejected their primary graft. Twelve patients with primary or secondary graft failure received T-cell replete bone marrow grafts from haploidentical donors and post-transplantation cyclophosphamide. The recommended conditioning regimen comprised rituximab 375 mg/m2, alemtuzumab 0.4 mg/kg, fludarabine 150 mg/m2, treosulfan 20–24 g/m2 and cyclophosphamide 29 mg/kg. After a median follow-up of 26 months (7–95), eleven of twelve patients (92%) are alive and well with complete donor chimerism in ten. Neutrophil and platelet engraftment were observed in all patients after a median of 18 days (15–61) and 39 days (15–191), respectively. Acute GVHD grade I was observed in 1/12 patients (8%) and mild chronic GVHD in 1/12 patients (8%). Viral reactivations and disease were frequent complications at 75% and 42%, respectively, but no death from infectious causes occurred. In summary, this retrospective analysis demonstrates that a post-transplantation cyclophosphamide-based HLA-haploidentical salvage HSCT after irradiation-free conditioning results in excellent engraftment and overall survival in children with non-malignant diseases

Papillary thyroid cancer associated with syndrome of inappropriate antidiuresis: a case report

<p>Abstract</p> <p>Introduction</p> <p>The syndrome of inappropriate antidiuresis is the most common cause of euvolemic hypo-osmolality. This syndrome is associated with a wide variety of diseases. However, its most frequent causes are related to malignancies, especially lung cancer. In this case report, we describe an unknown association of the syndrome of inappropriate antidiuresis with papillary thyroid cancer.</p> <p>Case presentation</p> <p>We present the case of a 71-year-old Caucasian, German woman with marked hyponatremia and neurological symptoms. After a detailed clinical investigation, the common causes of syndrome of inappropriate antidiuresis and other malignancies were ruled out. A thyroid nodule was detected by ultrasound and magnetic resonance imaging. Although fine needle aspiration cytology showed negative results, our patient underwent surgery. Papillary thyroid cancer was later diagnosed. After total thyroidectomy, a complete remission of the clinical symptoms occurred and our patient subsequently had iodine-131 radioactive therapy. Hyponatremia was no longer observed during the follow-up investigations.</p> <p>Conclusion</p> <p>This is the first reported case of paraneoplastic syndrome of inappropriate antidiuresis caused by papillary thyroid carcinoma. Since its symptoms occurred before the development of local symptoms, total thyroidectomy may provide a timely and efficient treatment for the underlying malignancy.</p

Telomerase and pluripotency factors jointly regulate stemness in pancreatic cancer stem cells

To assess the role of telomerase activity and telomere length in pancreatic CSCs we used different CSC enrichment methods (CD133, ALDH, sphere formation) in primary patient-derived pancreatic cancer cells. We show that CSCs have higher telomerase activity and longer telomeres than bulk tumor cells. Inhibition of telomerase activity, using genetic knockdown or pharmacological inhibitor (BIBR1532), resulted in CSC marker depletion, abrogation of sphere formation in vitro and reduced tumorigenicity in vivo. Furthermore, we identify a positive feedback loop between stemness factors (NANOG, OCT3/4, SOX2, KLF4) and telomerase, which is essential for the self-renewal of CSCs. Disruption of the balance between telomerase activity and stemness factors eliminates CSCs via induction of DNA damage and apoptosis in primary patient-derived pancreatic cancer samples, opening future perspectives to avoid CSC-driven tumor relapse. In the present study, we demonstrate that telomerase regulation is critical for the “stemness” maintenance in pancreatic CSCs and examine the effects of telomerase inhibition as a potential treatment option of pancreatic cancer. This may significantly promote our understanding of PDAC tumor biology and may result in improved treatment for pancreatic cancer patientsThis research was funded by a Max Eder Fellowship of the German Cancer Aid (111746), a German Cancer Aid Priority Program ‘Translational Oncology’ 70112505, by a Collaborative Research Centre grant (316249678—SFB 1279) of the German Research Foundation, and by a Hector Foundation Cancer Research grant (M65.1) to P.C.H., B.S.J. is supported by a Rámon y Cajal Merit Award (RYC- 2012-12104) from the Ministerio de Economía y Competitividad, Spain and a Coordinated grant (GC16173694BARB) from the Fundación Asociación Española Contra el Cáncer (AECC). K.W. is supported by a Baustein 3.2 by Ulm University

A multidimensional platform for the purification of non-coding RNA species

A renewed interest in non-coding RNA (ncRNA) has led to the discovery of novel RNA species and post-transcriptional ribonucleoside modifications, and an emerging appreciation for the role of ncRNA in RNA epigenetics. Although much can be learned by amplification-based analysis of ncRNA sequence and quantity, there is a significant need for direct analysis of RNA, which has led to numerous methods for purification of specific ncRNA molecules. However, no single method allows purification of the full range of cellular ncRNA species. To this end, we developed a multidimensional chromatographic platform to resolve, isolate and quantify all canonical ncRNAs in a single sample of cells or tissue, as well as novel ncRNA species. The applicability of the platform is demonstrated in analyses of ncRNA from bacteria, human cells and plasmodium-infected reticulocytes, as well as a viral RNA genome. Among the many potential applications of this platform are a system-level analysis of the dozens of modified ribonucleosides in ncRNA, characterization of novel long ncRNA species, enhanced detection of rare transcript variants and analysis of viral genomes.Singapore-MIT Alliance for Research and TechnologyNational Institute of Environmental Health Sciences (ES017010)National Institute of Environmental Health Sciences (ES002109

Multifaceted Regulation of Translational Readthrough by RNA Replication Elements in a Tombusvirus

Translational readthrough of stop codons by ribosomes is a recoding event used by a variety of viruses, including plus-strand RNA tombusviruses. Translation of the viral RNA-dependent RNA polymerase (RdRp) in tombusviruses is mediated using this strategy and we have investigated this process using a variety of in vitro and in vivo approaches. Our results indicate that readthrough generating the RdRp requires a novel long-range RNA-RNA interaction, spanning a distance of ∼3.5 kb, which occurs between a large RNA stem-loop located 3'-proximal to the stop codon and an RNA replication structure termed RIV at the 3'-end of the viral genome. Interestingly, this long-distance RNA-RNA interaction is modulated by mutually-exclusive RNA structures in RIV that represent a type of RNA switch. Moreover, a different long-range RNA-RNA interaction that was previously shown to be necessary for viral RNA replicase assembly was also required for efficient readthrough production of the RdRp. Accordingly, multiple replication-associated RNA elements are involved in modulating the readthrough event in tombusviruses and we propose an integrated mechanistic model to describe how this regulatory network could be advantageous by (i) providing a quality control system for culling truncated viral genomes at an early stage in the replication process, (ii) mediating cis-preferential replication of viral genomes, and (iii) coordinating translational readthrough of the RdRp with viral genome replication. Based on comparative sequence analysis and experimental data, basic elements of this regulatory model extend to other members of Tombusviridae, as well as to viruses outside of this family