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31.
Justyna
niechowska Piotr Paluch Tomasz Pawlak Grzegorz D. Bujacz Witold Danikiewicz Marek J. Potrzebowski 《RSC advances》2018,8(38):21354
In this work we propose a completely new approach for the synthesis of spirochlorin derivatives based on the use of an imino-keto intermediate formed in situ from 2-amino-5,10,15,20-tetraphenylporphyrins and inverse electron demand Diels–Alder (iEDDA) cycloaddition with 3,6-di-2-pyridyl-1,2,4,5-tetrazine. The mechanism of reaction was analyzed employing theoretical methods by comparing the difference in energy of Frontier Molecular Orbitals (FMO) for appropriate reagents. Ground-state molecular electrostatic (ESP) potential maps were employed as additional tools allowing explanation of the reactivity of substrates. The new class of spirochlorin compounds was fully characterized by means of mass spectrometry, IR, liquid and solid state NMR and X-ray crystallography. Correlation between molecular structure and optical properties for the obtained title compounds is discussed.Oxospirochlorins – novel analogs of porphyrinoids were synthesized and characterized by various methods including X-ray, NMR spectroscopy and mass spectrometry. 相似文献
32.
Aleksandra Mielczarek-Palacz Justyna SikoraZdzisława Kondera-Anasz Grzegorz Hauza 《Human immunology》2013
The aim of the study was to examine the concentrations of the soluble receptors and their ligands of CD30/CD30L and CD40/CD40L systems in the serum of women with ovarian tumor and in the ovarian cyst fluid of women with Cystadenoma serosum. The study included 120 women with ovarian tumors. As a control, sera were obtained from 60 healthy female volunteers. Concentrations of the sCD30, sCD30L, sCD40 and sCD40L in the serum and the ovarian cyst fluid were measured by ELISA enzyme-linked immunosorbent assay. Concentrations of both sCD30 and sCD30L in serum of women with ovarian tumors were significantly higher than in control (p < 0.0001). The highest serum receptor and its ligand levels were observed in women with ovarian cancer (p < 0.0001). Moreover, results showed significantly increased levels of sCD40 and sCD40L serum in women with ovarian tumors, as compared to the control group (p < 0.0001). The highest concentration of sCD40 in the serum of women with ovarian cancer and sCD40L in serum of women with Teratoma maturum (p < 0.0001) were observed. Impaired apoptosis among women with ovarian tumors is associated with the impairments of soluble CD30/CD30L and CD40/CD40L systems. Measurement of studied parameter concentrations in serum of women with ovarian tumors has been suggested to be a potential tool in monitoring of inflammatory. Evaluation of sCD30, sCD30L and sCD40 might be an early diagnostic marker in patients with the ovarian cancer. Concentrations of the studied parameters in the ovarian cyst fluid higher than the serum values suggest local suppression of the immune response. However, the final evaluation of the importance of measurement of serum levels of them requires further investigation. 相似文献
33.
Justyna Jarczak Ewa M. KościuczukPaweł Lisowski Nina StrzałkowskaArtur Jóźwik Jarosław HorbańczukJózef Krzyżewski Lech ZwierzchowskiEmilia Bagnicka 《Human immunology》2013
The widespread use of antibiotics has contributed to a huge increase in the number of resistant bacteria. New classes of drugs are therefore being developed of which defensins are a potential source. Defensins are a group of antimicrobial peptides found in different living organisms, involved in the first line of defense in their innate immune response against pathogens. This review summarizes the results of studies of this family of human antimicrobial peptides (AMPs). There is a special emphasis on describing the entire group and individual peptides, history of their discovery, their functions and expression sites. The results of the recent studies on the use of the biologically active peptides in human medicine are also presented. The pharmaceutical potential of human defensins cannot be ignored, especially considering their strong antimicrobial activity and properties such as low molecular weight, reduced immunogenicity, broad activity spectrum and resistance to proteolysis, but there are still many challenges and questions regarding the possibilities of their practical application. 相似文献
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35.
Bożena Moskwa Katarzyna Goździk Justyna Bień Anna Borecka Jakub Gawor Władysław Cabaj 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2013,58(2):149-154
Nematode worms of the genus Trichinella are one of the most widespread zoonotic pathogens. Natural transmission between hosts can only occur through the ingestion of infected meat. To date, two Trichinella species are known to be etiological agents of disease among domestic animals and wildlife in Poland: T. spiralis and T. britovi. In the last decades, since the administration of an oral vaccination against rabies, the red fox population in Poland has increased exponentially. The study area covers the Nowy Targ region: a mountainous area (585–1138 m above the sea) in southern Poland. Of 24 red foxes examined in the study, four were infected with Trichinella isolates: three were identified as T. britovi and one as T. pseudospiralis. The muscle of red foxes infected with T. britovi harboured 2.75, 3.11, 4.4 LPG and with T. pseudospiralis 0.36 LPG. Trichinella larvae were identified at species level by genomic and mitochondrial multiplex PCR, the products of which were sequenced for comparison with other sequences available in GenBank. The sequences obtained from the Polish T. pseudospiralis isolate, deposited in GenBank under the accession numbers JQ809660.1 and JQ809661.1, matched sequences already published in GenBank. Sequence comparison showed a 100% match with the large subunit ribosomal RNA gene of T. pseudospiralis isolate ISS 013, and a 96–95% match with those of T. pseudospiralis isolates ISS 141 and ISS 470. This is the first report of the identification of T. pseudospiralis larvae from red fox in Poland. 相似文献
36.
37.
Ivan Pavlenko Milan Saga Ivan Kuric Alexey Kotliar Yevheniia Basova Justyna Trojanowska Vitalii Ivanov 《Materials》2020,13(23)
The intensifying of the manufacturing process and increasing the efficiency of production planning of precise and non-rigid parts, mainly crankshafts, are the first-priority task in modern manufacturing. The use of various methods for controlling the cutting force under cylindrical infeed grinding and studying its impact on crankpin machining quality and accuracy can improve machining efficiency. The paper deals with developing a comprehensive scientific and methodological approach for determining the experimental dependence parameters’ quantitative values for cutting-force calculation in cylindrical infeed grinding. The main stages of creating a method for conducting a virtual experiment to determine the cutting force depending on the array of defining parameters obtained from experimental studies are outlined. It will make it possible to get recommendations for the formation of a valid route for crankpin machining. The research’s scientific novelty lies in the developed scientific and methodological approach for determining the cutting force, based on the integrated application of an artificial neural network (ANN) and multi-parametric quasi-linear regression analysis. In particular, on production conditions, the proposed method allows the rapid and accurate assessment of the technological parameters’ influence on the power characteristics for the cutting process. A numerical experiment was conducted to study the cutting force and evaluate its value’s primary indicators based on the proposed method. The study’s practical value lies in studying how to improve the grinding performance of the main bearing and connecting rod journals by intensifying cutting modes and optimizing the structure of machining cycles. 相似文献
38.
39.
Anne‐Lise Alloin Vincent Barlogis Pascal Auquier Audrey Contet Maryline Poiree François Demeocq Iris Herrmann Virginie Villes Yves Bertrand Dominique Plantaz Justyna Kanold Pascal Chastagner Hervé Chambost Nicolas Sirvent Gérard Michel 《British journal of haematology》2014,164(1):94-100
Corticosteroid and central nervous system (CNS) irradiation can induce cataract in childhood lymphoblastic leukaemia survivors. Few prospective studies with systematic ophthalmological evaluation have been published. Cataract was prospectively assessed by serial slip lamp tests in 517 patients. All had acute lymphoblastic leukaemia, all had been treated by chemotherapy with or without CNS irradiation, and none had received haematopoietic stem cell transplantation. Median ages at last evaluation and follow‐up duration from leukaemia diagnosis were 16·8 and 10·9 years, respectively. Cataract was observed in 21/517 patients (4·1%). Cumulative incidence was 4·5 ± 1·2% at 15 years and reached 26 ± 8·1% at 25 years. CNS irradiation was the only risk factor: prevalence was 11·1% in patients who had received irradiation and 2·8% in those who did not. We did not detect any steroid dose effect: cumulative dose was 5133 and 5190 mg/m2 in patients with and without cataract, respectively. Cataract occurrence did not significantly impact quality of life. We conclude that, in the range of steroid dose reported here, the cataract risk proves very low 15 years after treatment without CNS irradiation but an even more prolonged follow‐up is required because of potential very late occurrence. 相似文献
40.
Franziska Greifzu Justyna Pielecka-Fortuna Evgenia Kalogeraki Katja Krempler Plinio D. Favaro Oliver M. Schlüter Siegrid L?wel 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(3):1150-1155
Ocular dominance (OD) plasticity in mouse primary visual cortex (V1) declines during postnatal development and is absent beyond postnatal day 110 if mice are raised in standard cages (SCs). An enriched environment (EE) promotes OD plasticity in adult rats. Here, we explored cellular mechanisms of EE in mouse V1 and the therapeutic potential of EE to prevent impairments of plasticity after a cortical stroke. Using in vivo optical imaging, we observed that monocular deprivation in adult EE mice (i) caused a very strong OD plasticity previously only observed in 4-wk-old animals, (ii) restored already lost OD plasticity in adult SC-raised mice, and (iii) preserved OD plasticity after a stroke in the primary somatosensory cortex. Using patch-clamp electrophysiology in vitro, we also show that (iv) local inhibition was significantly reduced in V1 slices of adult EE mice and (v) the GABA/AMPA ratio was like that in 4-wk-old SC-raised animals. These observations were corroborated by in vivo analyses showing that diazepam treatment significantly reduced the OD shift of EE mice after monocular deprivation. Taken together, EE extended the sensitive phase for OD plasticity into late adulthood, rejuvenated V1 after 4 mo of SC-rearing, and protected adult mice from stroke-induced impairments of cortical plasticity. The EE effect was mediated most likely by preserving low juvenile levels of inhibition into adulthood, which potentially promoted adaptive changes in cortical circuits.Ocular dominance (OD) plasticity induced by monocular deprivation (MD) is one of the best studied models of experience-dependent plasticity in the mammalian cortex (1, 2). OD plasticity in primary visual cortex (V1) of C57BL/6J mice is maximal at 4 wk of age, declines after 2–3 mo, and is absent beyond postnatal day 110 (PD110) if animals are raised in standard cages (SCs) (3–6). In 4-wk-old mice, 4 d of MD are sufficient to induce an OD shift to the open eye; therefore, neurons in the binocular V1, which are usually dominated by the contralateral eye in rodents (3, 7), become activated more equally by both eyes (5, 8). This juvenile OD shift is predominantly mediated by a decrease in the visual cortical responses to the deprived eye (1, 9–11), whereas significant OD shifts in older animals up to PD110 need 7 d of MD and are mediated primarily by increased open-eye responses in V1. Raising animals in an enriched environment (EE) gives them the opportunity of enhanced physical, social, and cognitive stimulation and influences brain physiology and behavior in many ways (12, 13). It has been shown previously that EE enhances visual system development in rats (14) and mice (15–17), increases levels of the brain-derived neurotrophic factor and serotonin (18), reduces both extracellular GABA levels (18, 19) and the density of ECM perineuronal nets (PNNs) (19), and promotes OD plasticity in adult and aging rats (18–21). Here, we explored cellular mechanisms of EE in V1 of mice and the therapeutic potential of EE to prevent impairments of plasticity after a cortical stroke. Furthermore, we studied whether EE would prolong the sensitive phase for OD plasticity into adulthood and also restore this form of plasticity in mice that were raised in SC until PD110 (i.e., in animals that were already beyond their sensitive phase for OD plasticity). Despite pharmacological detection of in vivo GABA levels, suggesting that EE reduces intracortical inhibition, direct electrophysiological evidence is still missing. We therefore recorded GABA, AMPA, and NMDA currents in slices from EE- and SC-raised mice and also tested the efficacy of diazepam injections to abolish OD plasticity of EE mice in vivo. Finally, we studied whether raising mice in EE would protect them from lesion-induced impairments of OD plasticity. Our results show that raising mice in EE preserved OD plasticity into late adulthood rejuvenated the brain after 3 mo of SC-rearing, and protected adult mice from stroke-induced impairments of cortical plasticity. Our electrophysiological measurements and diazepam treatment indicate that the plasticity-promoting effect of EE was primarily mediated by reduced intracortical inhibition compared with SC-raised mice. These results suggest EE as a preventive intervention to enhance and preserve plasticity in adulthood and after a cortical lesion. 相似文献