Intestinal stem cell regulation by the hexosamine biosynthesis pathway in D. melanogaster

The intestinal stem cells (ISC) of the D. melanogaster midgut, which is the functional analogue to mammalian small intestine, are highly responsive to changes in nutrition. ISC employ the hexosamine biosynthesis pathway (HBP) to monitor nutritional status. HBP activity is an essential facilitator for insulin signaling-induced ISC proliferation. The midgut’s compartmentalized structure allows the study of many regulatory pathways. The regions of the midgut are characterized by distinct gene expression patterns, different histology, and physiological functions. The homeostatic regulation of intestine in fluctuating dietary conditions is poorly understood. In this study the interaction of the HBP and nutrition in the ISC population of the midgut were studied via confocal microscopy and the Longitudinal Analysis of the Midgut (LAM). The HBP was activated in different dietary conditions in ISC by feeding the flies with Glucosamine or by expressing the rate limiting enzyme Gfat2 in the ISC and their progeny. The increased clonal cell numbers suggest higher cellular turnover leading to higher stem cell proliferation rate in comparison fed versus starved dietary conditions. LAM gives a region-specific elevation of the clonal numbers of the cell. When experimenting which nutrients mediate the proliferative capacity of stem cells, we found that removing essential amino acids have similar effect on R4 region compared to the starved versus fed condition. Our results give new insights to the nutritional response and the region-specific activation for further research in connection with the HBP activation

High tick abundance and diversity of tick-borne pathogens in a Finnish city

The sheep tick Ixodes ricinus is the primary vector for various zoonotic diseases, including Lyme borreliosis and tick-borne encephalitis (TBE), in Europe. Because both abundance of ticks and prevalence of tick-borne pathogens in these organisms have increased in many locations and under different environments, we designed a study to survey the occurrence of ticks and pathogens in an urban area, namely, the city of Turku, in SW Finland. In summer 2017, we collected >700 ticks, primarily from city parks, suburban forest patches, and recreational areas. Comprehensive subsets of ticks were screened for presence of all common tick-borne pathogens. Half of the ticks carried at least one pathogen. The most common pathogens detected were the causative agents of Lyme borreliosis, i.e., bacteria belonging to the Borrelia burgdorferi sensu lato group. Their prevalence was 37% in nymphal and 47% in adult ticks, which are high in comparison with surveys conducted elsewhere in northern Europe. Similarly, Rickettsia spp. (primarily R. helvetica) were also detected in a relatively high proportion of the samples (11% of both nymphs and adults). The TBE virus was not found in a relatively small subsample, but we detected (albeit at a low prevalence of 0–6% of nymphs and adults) the bacterial pathogens Borrelia miyamotoi, Anaplasma phagocytophilum and Candidatus Neoehrlichia mikurensis and the protozoan Babesia spp., which are also known agents of zoonotic diseases. The relatively high abundance of ticks and high diversity and overall prevalence of tick-borne pathogens suggest a lively and dense presence of mammalian and avian tick hosts in the city. Our results indicate a higher risk of encountering tick-borne pathogens in urbanized areas of southern Finland than previously known. Moreover, the possibility of acquiring tick-borne diseases from urban environments likely exists throughout most of Europe, and it should be acknowledged by health care professionals.</p

High tick abundance and diversity of tick-borne pathogens in a Finnish city

The sheep tick Ixodes ricinus is the primary vector for various zoonotic diseases, including Lyme borreliosis and tick-borne encephalitis (TBE), in Europe. Because both abundance of ticks and prevalence of tick-borne pathogens in these organisms have increased in many locations and under different environments, we designed a study to survey the occurrence of ticks and pathogens in an urban area, namely, the city of Turku, in SW Finland. In summer 2017, we collected >700 ticks, primarily from city parks, suburban forest patches, and recreational areas. Comprehensive subsets of ticks were screened for presence of all common tick-borne pathogens. Half of the ticks carried at least one pathogen. The most common pathogens detected were the causative agents of Lyme borreliosis, i.e., bacteria belonging to the Borrelia burgdorferi sensu lato group. Their prevalence was 37% in nymphal and 47% in adult ticks, which are high in comparison with surveys conducted elsewhere in northern Europe. Similarly, Rickettsia spp. (primarily R. helvetica) were also detected in a relatively high proportion of the samples (11% of both nymphs and adults). The TBE virus was not found in a relatively small subsample, but we detected (albeit at a low prevalence of 0–6% of nymphs and adults) the bacterial pathogens Borrelia miyamotoi, Anaplasma phagocytophilum and Candidatus Neoehrlichia mikurensis and the protozoan Babesia spp., which are also known agents of zoonotic diseases. The relatively high abundance of ticks and high diversity and overall prevalence of tick-borne pathogens suggest a lively and dense presence of mammalian and avian tick hosts in the city. Our results indicate a higher risk of encountering tick-borne pathogens in urbanized areas of southern Finland than previously known. Moreover, the possibility of acquiring tick-borne diseases from urban environments likely exists throughout most of Europe, and it should be acknowledged by health care professionals.Peer reviewe

Irrigation deficit turns almond by-products into a valuable source of antimicrobial (poly)phenols

[EN] Almond (Prunus dulcis (Mill.) D. A. Webb) production keeps an increasing trend worldwide, leading to augment in generation of harmful by-products that should be valorized as a source of bioactive phytochemicals with application in the development of new added-value products. The assessment of almond hulls and skins on their (poly)phenolic composition was developed upon two seasons, under five irrigation regimes, regarding total phenolics, flavonoids, and ortho-diphenols, as well as individual phenolic compounds analyzed by High Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD). As functional tests, extracts were assessed on their radical scavenging activity in vitro and reducing power, and screened on their antimicrobial activity against multidrug resistant bacterial pathogens. The phenolic profile and antioxidant activities were evaluated in blanching water as well. Naringenin-7-O-glucoside and isorhamnetin-3-O-rutinoside were the most abundant phenolics in almond hulls and skins. Influence of irrigation treatments and season on phenolic content differed among by-products; hulls being more influenced by irrigation and skins by the agro-climatic conditions. The synthesis of individual phenolics was more influenced by season than treatment. According to the chemical and biological correlations, the presence of (poly)phenols seems to be responsible for the antioxidant and antimicrobial properties revealed. The knowledge generated upon the present work contributes to understand the variability of almond by-products composition attributable to seasonal and irrigation conditions, and to envisage valorization alternatives for these under explored residues and blanching water.IP acknowledges the financial support provided by the FCT-Portuguese Foundation for Science and Technology (SFRH/BD/52539/2014), under the Doctoral Programme Agricultural Production Chains from fork to farm (PD/00122/2012). This work was also supported by National Funds by FCT - Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2019. RDP was supported by a Postdoctoral Contract (Juan de la Cierva de Incorporación ICJI-2015-25373) from the Ministry of Economy, Industry and Competitiveness of Spain.Prgomet, I.; Gonçalves, B.; Domínguez-Perles, R.; Santos, R.; Saavedra, MJ.; Aires, A.; Pascual-Seva, N.... (2019). Irrigation deficit turns almond by-products into a valuable source of antimicrobial (poly)phenols. Industrial Crops and Products. 132:186-196. https://doi.org/10.1016/j.indcrop.2019.02.024S18619613

Computer simulations of direct DNA alkylation with acrylonitrile

V današnjem času smo povsod obdani s kancerogenimi snovmi, zato je naša naloga, da spoznamo, kako te snovi vplivajo na naše telo oz. kakšne spremembe povzročijo na dednem materialu DNK. Ena izmed teh snovi je akrilonitril, za katerega se je do sedaj predvidevalo, da se v telesu presnavlja predvsem po oksidativnem mehanizmu, saj se mehanizem direktne alkilacije oz. Michaelove adicije akrilonitrila na DNK še ni dovolj preučil. Preučevanja mehanizma direktne alkilacije akrilonitrila na DNK smo se posledično lotili v tem magistrskem delu. Mehanizem Michaelove adicije smo preučevali preko računalniških kvantnomehanskih simulacij na podlagi več različnih ab initio metod s programskim paketom Gaussian 09. Za realnejši izračun smo uporabili tudi implicitne modele vode, ki deluje kot topilo za reakcije v bioloških sistemih. Solvatacijske metode, ki smo jih uporabili, predstavljajo model polarizabilnega kontinuuma, ki spada v skupino metod samouglašenega reakcijskega polja, metoda Langevinovih dipolov in model AMSOL za semiempirične metode. Na podlagi aktivacijskih prostih energij smo ugotovili, da je reakcija direktne alkilacije z vidika energijske pregrade povsem mogoča. Rezultati so pokazali, da ima najnižjo aktivacijsko prosto energijo gvanin in je zatorej najbolj podvržen direktni alkilaciji s strani akrilonitrila, kar je tudi eksperimentalo potrjeno. Vendar pa so energijsko ugodne tudi reakcije adenina in citozina. Primerjava naših rezultatov z rezultati adicije cianoetilen oksida na DNK so razkrili, da je alkilacija akrilonitrila na DNK lahko celo energijsko ugodnejša, kar pomeni, da je mehanizem direktne alkilacije morda celo verjetnejši od oksidativnega mehanizma presnove akrilonitrila. Na podlagi dobljenih izsledkov smo torej pokazali, da je ključnega pomena nadaljevati z raziskavami mehanizma Michaelove adicije akrilonitrila na DNK, saj lahko le-ta predstavlja enega od ključnih mehanizmov kancerogeneze.Nowadays carcinogenic substances surround us at every step, so our goal should become to get acquainted with the effects they have on our bodies and with what kind of modifications they can cause to our DNA. Acrylonitrile is a known carcinogenic substances which can be metabolised in the body via two different pathways, and until now it was believed that the oxidative pathway represents the major one, mainly because direct alkylation - the Michael addition pathway - had not been studiedin sufficient detail. Studying the direct alkylation mechanism was therefore the objective of this master thesis. We have studied this mechanism through quantum mechanical simulations using several ab initio methods incorporated in the Gaussian 09 series of programs. To compare the theoretical results to real systems and thus incorporate the solvent effects we have used implicit water models: the polarisable continuum model that belongs to the group of self-consistent reaction field methods, the Langevine dipoles method, and the AMSOL model for semiempirical calculations. On the basis of activation free energy we have come to conclusion that direct alkylation of DNA by acrylonitrile is perfectly plausable. The results have in complience with experiment shown that among DNA bases guanine has the lowest activation free energy and is therefore the most reactive with acrylonitrile. However, the energy bariers for adenine and cytozine are very similar to those of guanine and are low enough to cause direct alkylation by acrylonitrile as well. The comparison of our results with the results of cyanoethylene oxide addition to DNA have shown that investigated mechanism might even be more energetically favorable than the oxidative mechanism, thus possibly making direct Michael addition more the plausable mechanism for the metabolism of acrylonitrile. With these results we have shown that further studies of the Michael addition of acrylonitrile to DNA are needed, as it may represent one of the carcinogenic mechanisms

Influence of Company Size on Accounting Information for Decision-Making of Management

The aim of this paper is to show the importance of accounting information for management, especially in medium-sized companies. Sampling was carried out according to the accidental principle, after which we selected 300 medium-sized and large companies. We used the questionnaire, which was standardized and implemented online. Two hypothesis were tested with a chi-square test and contingency table. In this study of Slovenian large and medium companies, we want to find out whether the size of the company has an impact on organizing a specific controlling service in a company and whether, in large companies, heads of accounting are more often members of management than in mediumsized enterprises. We discovered a bias between organizing a specific controlling department and the size of a company, and that large companies have more often organized a special controlling service than medium-sized enterprises. We also discovered the accounting officer’s membership in a company’s management team is not related to the size of a company. The results of the research could be used in controlling in medium-sized companies, where we suggest that management accounting in these companies is part of management decisions