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Transcriptomic analysis of isolates from the malaria parasite (Plasmodium falciparum) in the Greater Mekong Subregion of Southeast Asia identifies gene expression patterns that are correlated with resistance to a common anti-malaria drug, artemisinin.

Resistance of the human malaria parasites, Plasmodium falciparum, to artemisinins is now fully established in Southeast Asia and is gradually emerging in Sub-Saharan Africa. Although nonsynonymous SNPs in the pfk13 Kelch-repeat propeller (KREP) domain are clearly associated with artemisinin resistance, their functional relevance requires cooperation with other genetic factors/alterations of the P. falciparum genome, collectively referred to as genetic background. Here we provide experimental evidence that P. falciparum cyclophilin 19B (PfCYP19B) may represent one putative factor in this genetic background, contributing to artemisinin resistance via its increased expression. We show that overexpression of PfCYP19B in vitro drives limited but significant resistance to not only artemisinin but also piperaquine, an important partner drug in artemisinin-based combination therapies. We showed that PfCYP19B acts as a negative regulator of the integrated stress response (ISR) pathway by modulating levels of phosphorylated eIF2α (eIF2α-P). Curiously, artemisinin and piperaquine affect eIF2α-P in an inverse direction that in both cases can be modulated by PfCYP19B towards resistance. Here we also provide evidence that the upregulation of PfCYP19B in the drug-resistant parasites appears to be maintained by a short tandem repeat (SRT) sequence polymorphism in the gene's promoter region. These results support a model that artemisinin (and other drugs) resistance mechanisms are complex genetic traits being contributed to by altered expression of multiple genes driven by genetic polymorphism at their promoter regions.

Abstract Background Sequencing technology advancements opened new opportunities to use transcriptomics for studying malaria pathology and epidemiology. Even though in recent years the study of whole parasite transcriptome proved to be essential in understanding parasite biology there is no compiled up-to-date reference protocol for the efficient generation of transcriptome data from growing number of samples. Here, a comprehensive methodology on how to preserve, extract, amplify, and sequence full-length mRNA transcripts from Plasmodium-infected blood samples is presented that can be fully streamlined for high-throughput studies. Results The utility of various commercially available RNA-preserving reagents in a range of storage conditions was evaluated. Similarly, several RNA extraction protocols were compared and the one most suitable method for the extraction of high-quality total RNA from low-parasitaemia and low-volume blood samples was established. Furthermore, the criteria needed to evaluate the quality and integrity of Plasmodium RNA in the presence of human RNA was updated. Optimization of SMART-seq2 amplification method to better suit AT-rich Plasmodium falciparum RNA samples allowed us to generate high-quality transcriptomes from as little as 10 ng of total RNA and a lower parasitaemia limit of 0.05%. Finally, a modified method for depletion of unwanted human haemoglobin transcripts using in vitro CRISPR-Cas9 treatment was designed, thus improving parasite transcriptome coverage in low parasitaemia samples. To prove the functionality of the pipeline for both laboratory and field strains, the highest 2-hour resolution RNA-seq transcriptome for P. falciparum 3D7 intraerythrocytic life cycle available to date was generated, and the entire protocol was applied to create the largest transcriptome data from Southeast Asian field isolates. Conclusions Overall, the presented methodology is an inclusive pipeline for generation of good quality transcriptomic data from a diverse range of Plasmodium-infected blood samples with varying parasitaemia and RNA inputs. The flexibility of this pipeline to be adapted to robotic handling will facilitate both small and large-scale future transcriptomic studies in the field of malaria.

Concrete is an ecological material with a high potential to adapt to specific operating conditions, and the lowest carbon footprint as it is made from local raw materials—aggregate, cement, water, admixtures, and mineral additives. It is the most widely used composite material among those that are man-made and second only to water in the entire range of materials used. The aim of this research was to assess the possibility of using fly ash from the thermal treatment of sewage sludge as an alternative additive to concretes resistant to environmental influences occurring in communication tunnels. A concrete mix based on CEM I 42.5R Portland cement with various ash content of 0–20% of the cement mass was designed for the experimental work. In the course of the experimental work, the compressive strength was measured after three maturing periods, and the influence of both high temperature and the material modification on the course of carbonation were determined. The test results confirm the possibility of producing plain concrete, modified with fly ash obtained from the thermal treatment of sewage sludge. The highest average compressive strength of 43.6 MPa, 45.6 MPa, and 51.2 MPa after 28, 56 and 720 days of maturation, respectively, was for concrete containing 10% ash.

Conducted examinations were aimed at examining to what degree formal values of the advertising value equivalent (AVE) are ahead of their real value. The reason behind setting the real amount of the AVE is that many sponsoring entities supporting sport treat this factor as the main determinant in evaluation of their sponsoring campaign, even though there are justified doubts about its credibility (Hagyari et al., 2016). During the implementation of studies a thesis was adopted that the official value of the AVE is elevated, and hence distort the process of evaluation of sponsorship. Conducted research involved determining number of visual contacts of respondents with logotypes of chosen sponsors while watching video material with volleyball matches. Research process was based on an eye-tracker. Obtained data was used to determine real values of AVE obtained by each brand. Obtained findings allowed to accept the thesis, as applied innovative test procedure confirmed that real value of the AVE, which had been set, was significantly lower in case of every examined enterprise: differences between the official and real value of the AVE fluctuated from 57% to 96%. Sponsoring enterprises shouldn’t base the evaluation of their sponsorship campaigns on official AVE as obtained data may lead to erroneous conclusions.

The article was composed on the basis of research conducted in Nadwislanska Travel Agency (NAT). One of numerous research goals included the extent to which outsourcing was used in each entity that formed NAT. Additional theoretical aim of this article was to specify benefits that this management concept might bring to travel organizations. Subject literature analysis allowed to create a list of potential benefits of outsourcing that was presented in the first part of the article. In the following part, own research results conducted in NAT were listed and on their basis research hypotheses were verified. Main research hypothesis, which assumed that all entities belonging to NAT used outsourcing in at least a couple of their areas of operation, was rejected as within NAT a common strategy of outsourcing was not established.

W artykule przedstawiono wyniki badań dotyczące wykorzystania miejsc noclegowych w hotelach Nadwiślańskiej Agencji Turystycznej (NAT). Badania zostały przeprowadzone za lata 2014–2016. Analizie zostało objętych osiem hoteli należących do NAT. Spośród wszystkich obiektów objętych badaniem i po uwzględnieniu całkowitej liczby udzielonych noclegów okazało się, że najwyższy wskaźnik obłożenia miejsc noclegowych we wszystkich badanych okresach, tj. od 2014 do 2016 roku miał hotel „Górnik”. Najniższą wartość tego wskaźnika odnotowano w przypadku hotelu „Neptun” w 2014 roku oraz w hotelu „Za Wydmą” w roku 2015 i 2016. W przypadku hoteli: „Górnik”, „Jawor” i „Neptun” w okresie badawczym zaobserwowano tendencję wzrostową, zaś w pozostałych obiektach odnotowano wahania wzrostu bądź spadku analizowanego zjawiska. Dokonując analizy skumulowanej liczby osobonoclegów udzielonych w hotelach NAT w 2016 roku z wykorzystaniem indeksów jednopodstawowych ustalono poziom najwyższego oraz najniższego spadku badanego zjawiska w stosunku do przyjętego okresu bazowego. Uwzględniając ogół korzystających, najwyższy spadek liczby udzielonych noclegów w odniesieniu do miesiąca lipca, który przyjęto za podstawę wyznaczenia indeksów odnotowano w grudniu 79,21%, zaś najniższy w sierpniu 6,02%. Na podstawie przeprowadzonych badań można stwierdzić, iż poziom wykorzystania miejsc noclegowych w większości badanych obiektów jest zadawalający. Wartości wskaźnika obłożenia w hotelach należących do Nadwiślańskiej Agencji Turystycznej nie odbiegały od wartości odnotowanych w analogicznym okresie w Polsce przez Główny Urząd Statystyczny, a w niektórych przypadkach znacząco te wartości przewyższał.