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51.
Katarzyna Ginda Martyna Bezulska Małgorzata Ziółkiewicz Jarosław Dziadek Jolanta Zakrzewska‐Czerwińska Dagmara Jakimowicz 《Molecular microbiology》2013,87(5):998-1012
Mycobacteria are among the clinically most important pathogens, but still not much is known about the mechanisms of their cell cycle control. Previous studies suggested that the genes encoding ParA and ParB (ATPase and DNA binding protein, respectively, required for active chromosome segregation) may be essential in Mycobacterium tuberculosis. Further research has demonstrated that a Mycobacterium smegmatis parB deletion mutant was viable but exhibited a chromosome segregation defect. Here, we address the question if ParA is required for the growth of M. smegmatis, and which cell cycle processes it affects. Our data show that parA may be deleted, but its deletion leads to growth inhibition and severe disturbances of chromosome segregation and septum positioning. Similar defects are also caused by ParA overproduction. EGFP–ParA localizes as pole‐associated complexes connected with a patch of fluorescence accompanying two ParB complexes. Observed aberrations in the number and positioning of ParB complexes in the parA deletion mutant indicate that ParA is required for the proper localization of the ParB complexes. Furthermore, it is shown that ParA colocalizes and interacts with the polar growth determinant Wag31 (DivIVA homologue). Our results demonstrate that mycobacterial ParA mediates chromosome segregation and co‐ordinates it with cell division and elongation. 相似文献
52.
Sofia Theodoropoulou Katarzyna Brodowska Maki Kayama Yuki Morizane Joan W. Miller Evangelos S. Gragoudas Demetrios G. Vavvas 《PloS one》2013,8(1)
5-Aminoimidazole-4-carboxamide-1-β-4-ribofuranoside (AICAR), an analog of AMP is widely used as an activator of AMP-kinase (AMPK), a protein that regulates the responses of the cell to energy change. Recently, we showed that AICAR-induced AMPK activation inhibits the growth of retinoblastoma cells in vitro by decreasing cyclins and by inducing apoptosis and S-phase arrest. In this study, we investigated the effects of AMPK activator AICAR on the growth of retinoblastoma in vivo. Intraperitoneal injection of AICAR resulted in 48% growth inhibition of Y79 retinoblastoma cell tumors in mice. Tumors isolated from mice treated with AICAR had decreased expression of Ki67 and increased apoptotic cells (TUNEL positive) compared with the control. In addition, AICAR treatment suppressed significantly tumor vessel density and macrophage infiltration. We also showed that AICAR administration resulted in AMPK activation and mTOR pathway inhibition. Paradoxically observed down-regulation of p21, which indicates that p21 may have a novel function of an oncogene in retinoblastoma tumor. Our results indicate that AICAR treatment inhibited the growth of retinoblastoma tumor in vivo via AMPK/mTORC1 pathway and by apoptogenic, anti-proliferative, anti-angiogenesis mechanism. AICAR is a promising novel non-chemotherapeutic drug that may be effective as an adjuvant in treating Retinoblastoma. 相似文献
53.
Magdalena Banas Katarzyna Zabieglo Gopinath Kasetty Monika Kapinska-Mrowiecka Julia Borowczyk Justyna Drukala Krzysztof Murzyn Brian A. Zabel Eugene C. Butcher Jens M. Schroeder Artur Schmidtchen Joanna Cichy 《PloS one》2013,8(3)
Chemerin, a chemoattractant ligand for chemokine-like receptor 1 (CMKLR1) is predicted to share similar tertiary structure with antibacterial cathelicidins. Recombinant chemerin has antimicrobial activity. Here we show that endogenous chemerin is abundant in human epidermis, and that inhibition of bacteria growth by exudates from organ cultures of primary human skin keratinocytes is largely chemerin-dependent. Using a panel of overlapping chemerin-derived synthetic peptides, we demonstrate that the antibacterial activity of chemerin is primarily mediated by Val66-Pro85, which causes direct bacterial lysis. Therefore, chemerin is an antimicrobial agent in human skin. 相似文献
54.
Lipid droplets formation in human endothelial cells in response to polyunsaturated fatty acids and 1‐methyl‐nicotinamide (MNA); confocal Raman imaging and fluorescence microscopy studies 下载免费PDF全文
In this work the formation of lipid droplets (LDs) in human endothelial cells culture in response to the uptake of polyunsaturated fatty acids (PUFAs) was studied. Additionally, an effect of 1‐methylnicotinamide (MNA) on the process of LDs formation was investigated. LDs have been previously described structurally and to some degree biochemically, however neither the precise function of LDs nor the factors responsible for LD induction have been clarified. Lipid droplets, sometimes referred in the literature as lipid bodies are organelles known to regulate neutrophil, eosinophil, or tumor cell functions but their presence and function in the endothelium is largely unexplored. 3D linear Raman spectroscopy was used to study LDs formation in vitro in a single endothelial cell. The method provides information about distribution and size of LDs as well as their composition. The incubation of endothelial cells with various PUFAs resulted in formation of LDs. As a complementary method for LDs identification a fluorescence microscopy was applied. Fluorescence measurements confirmed the Raman results suggesting endothelial cells uptake of PUFAs and subsequent LDs formation in the cytoplasm of the endothelium. Furthermore, MNA seem to potentiate intracellular uptake of PUFAs to the endothelium that may bear physiological and pharmacological significance.
55.
Filip Boratyński Katarzyna Dancewicz Marlena Paprocka Beata Gabry? Czes?aw Wawrzeńczyk 《PloS one》2016,11(1)
The enantiomerically enriched γ- and δ-decalactones (4a and 4b) were prepared from corresponding racemic primary-secondary 1,4- and 1,5-diols (1a and 1b), as products of enzymatic oxidation catalyzed by different alcohol dehydrogenases. The results of biotransformations indicated that the oxidation processes catalyzed by alcohol dehydrogenase (HLADH), both isolated from horse liver and recombinant in Escherichia coli, were characterized by the highest degree of conversion with moderate enantioselectivity of the reaction. Useful, environmentally friendly extraction procedure of decalactones (4a and 4b) based on hydrodistillation using a Deryng apparatus was developed. Both racemic lactones (4a and 4b), as well as their enantiomerically enriched isomers, were tested for feeding deterrent activity against Myzus persicae. The effect of these compounds on probing, feeding and settling behavior of M. persicae was studied in vivo. The deterrent activity of decalactones (4a and 4b) against aphids depended on the size of the lactone ring and the enantiomeric purity of the compounds. δ-Decalactone (4b) appeared inactive against M. persicae while γ-decalactone (4a) restrained aphid probing at ingestional phase. Only (–)-(S)-γ-decalactone (4a) had strong and durable (i.e. lasting for at least 24 hours) limiting effect, expressed at phloem level. 相似文献
56.
Katarzyna Ciach Marek Niedoszytko Anna Abacjew-Chmylko Izabela Pabin Przemyslaw Adamski Katarzyna Leszczynska Krzysztof Preis Hanna Olszewska Dariusz G. Wydra Rita Hansdorfer-Korzon 《PloS one》2016,11(1)
Objective
To present current guidelines regarding treatment of mastocytosis in pregnancy on the example of observed patients.Design
Case control national study.Setting
Polish Center of the European Competence Network on Mastocytosis (ECNM).Population or Sample
23 singleton spontaneous pregnancies in 17 women diagnosed with mastocytosis in years 1999–2014, before becoming pregnant.Methods
Prospective analysis outcomes of pregnancies and deliveries.Main Outcome Measures
Survey developed in cooperation with the Spanish Instituto de Estudios de Mastocitosis de Castilla-La Mancha (CLMast), Hospital Virgen del Valle, Toledo, Red Espańola de Mastocitosis (REMA), Spain.Results
All 23 pregnancies resulted from natural conception. Obstetrical complications recorded in the first trimester included spontaneous miscarriage (5 pregnancies). Four patients delivered preterm, including one delivery due to preeclampsia at 26 weeks which resulted with neonate death due to extreme prematurity. Five women delivered via cesarean: four due to obstetrical indications and one due to mastocytosis, during which no anesthesia related complications were recorded. Of patients delivering vaginally, two received extradural anesthesia, three required oxytocin infusion due to uterine hypotonia. No labor complications were recorded. In one woman with pregnancy-induced hypertension, early puerperium was complicated by the presence of persistent arterial hypertension. One neonate was born with the signs of cutaneous mastocytosis. Another neonate was diagnosed with Patau syndrome. Four women were treated for mastocytosis prior to conception and continued therapy after becoming pregnant. One patient was put on medications in the first trimester due to worsening of her symptoms. Pregnancy exerted only a slight effect on the intensity and frequency of mastocytosis-related symptoms observed. Worsening of the disease-related symptoms was documented in only four patients (23%). None of the patients showed the signs of anaphylaxis, either before becoming pregnant, or during pregnancy and puerperium.Conclusions
There is no contraindication to pregnancy when mastocystosis-related pathologies are under appropriate medical control. 相似文献57.
Edyta Paradowska Agnieszka Jab?ońska Miros?awa Studzińska Katarzyna Skowrońska Patrycja Suski Ma?gorzata Wi?niewska-Ligier Teresa Wo?niakowska-G?sicka Dorota Nowakowska Zuzanna Gaj Jan Wilczyński Zbigniew J. Le?nikowski 《PloS one》2016,11(4)
Toll-like receptor 9 (TLR9) recognizes non-methylated viral CpG-containing DNA and serves as a pattern recognition receptor that signals the presence of human cytomegalovirus (HCMV). Here, we present the genotype distribution of single-nucleotide polymorphisms (SNPs) of the TLR9 gene in infants and the relationship between TLR9 polymorphisms and HCMV infection. Four polymorphisms (-1237T/C, rs5743836; -1486T/C, rs187084; 1174G/A, rs352139; and 2848C/T, rs352140) in the TLR9 gene were genotyped in 72 infants with symptomatic HCMV infection and 70 healthy individuals. SNP genotyping was performed by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Digested fragments were separated and identified by capillary electrophoresis. The HCMV DNA copy number was measured by a quantitative real-time PCR assay. We found an increased frequency of heterozygous genotypes TLR9 -1486T/C and 2848C/T in infants with HCMV infection compared with uninfected cases. Heterozygous variants of these two SNPs increased the risk of HCMV disease in children (P = 0.044 and P = 0.029, respectively). In infants with a mutation present in at least one allele of -1486T/C and 2848C/T SNPs, a trend towards increased risk of cytomegaly was confirmed after Bonferroni’s correction for multiple testing (Pc = 0.063). The rs352139 GG genotype showed a significantly reduced relative risk for HCMV infection (Pc = 0.006). In contrast, the -1237T/C SNP was not related to viral infection. We found no evidence for linkage disequilibrium with the four examined TLR9 SNPs. The findings suggest that the TLR9 -1486T/C and 2848C/T polymorphisms could be a genetic risk factor for the development of HCMV disease. 相似文献
58.
Jagoda Kicielińska Agnieszka Szczygie? Joanna Rossowska Natalia Anger Katarzyna Kempińska Marta ?witalska Marta Kaszowska Joanna Wietrzyk Janusz Boratyński El?bieta Pajtasz-Piasecka 《PloS one》2016,11(2)
Introduction
Polymyxin B (PmB) belongs to the group of cyclic peptide antibiotics, which neutralize the activity of LPS by binding to lipid A. The aim of this study was to analyze the effect of PmB on the biological activity of lipooligosaccharide (LOS E. coli B,rough form of LPS) in vitro and in experimental metastasis models.Results
Cultures of murine macrophage J774A.1 cells and murine bone marrow-derived dendritic cells (BM-DC) stimulated in vitro with LOS and supplemented with PmB demonstrated a decrease in inflammatory cytokine production (IL-6, IL-10, TNF-α) and down-regulation of CD40, CD80, CD86 and MHC class II molecule expression. Additionally, PmB suspended in drinking water was given to the C57BL/6 mice seven or five days prior to the intravenous injection of B16 or LLC cells and intraperitoneal application of LOS. This strategy of PmB administration was continued throughout the duration of the experiments (29 or 21 days). In B16 model, statistically significant decrease in the number of metastases in mice treated with PmB and LOS (p<0.01) was found on the 14th day of the experiments, whereas the most intensive changes in surface-antigen expression and ex vivo production of IL-6, IL-1β and TNF-α by peritoneal cells were observed 7 days earlier. By contrast, antigen expression and ex vivo production of IL-6, IL-10, IFN-γ by splenocytes remained relatively high and stable. Statistically significant decrease in LLC metastases number was observed after the application of LOS (p<0.01) and in the group of mice preconditioned by PmB and subsequently treated with LOS (LOS + PmB, p<0.01).Conclusions
In conclusion, prolonged in vivo application of PmB was not able to neutralize the LOS-induced immune cell activity but its presence in the organism of treated mice was important in modulation of the LOS-mediated response against the development of metastases. 相似文献59.
Photographic identity documents (IDs) are commonly used despite clear evidence that unfamiliar face matching is a difficult and error-prone task. The current study set out to examine the performance of seven individuals with extraordinary face recognition memory, so called “super recognisers” (SRs), on two face matching tasks resembling border control identity checks. In Experiment 1, the SRs as a group outperformed control participants on the “Glasgow Face Matching Test”, and some case-by-case comparisons also reached significance. In Experiment 2, a perceptually difficult face matching task was used: the “Models Face Matching Test”. Once again, SRs outperformed controls both on group and mostly in case-by-case analyses. These findings suggest that SRs are considerably better at face matching than typical perceivers, and would make proficient personnel for border control agencies. 相似文献
60.
Tadeusz Osadnik Joanna Katarzyna Strzelczyk Rafa? Regu?a Kamil Bujak Martyna Fronczek Ma?gorzata Gonera Marcin Gawlita Jaros?aw Wasilewski Andrzej Lekston Anna Kurek Marek Gierlotka Przemys?aw Trzeciak Micha? Hawranek Zofia Ostrowska Andrzej Wiczkowski Lech Poloński Mariusz G?sior 《PloS one》2016,11(3)