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991.
We investigated the effect of a triterpene saponoside from Lysimachia thyrsiflora L. upon the viability, proliferation, morphology and cell motility of human melanoma HTB-140 cells and human skin fibroblasts
(HSFs). The compound, denoted LTS-4, decreased the viability and rate of cell growth of both cell types in a time-and dose-dependent
manner, and proved cytotoxic against cancer cells at significantly lower concentrations than for fibroblasts. LTS-4 also affected
the morphology of the examined cells, causing vacuolisation and actin cytoskeleton disintegration, and had an inhibitory effect
on the tumour cell motility. 相似文献
992.
Jolanta Kedzierska Beata Piatkowska-Jakubas Anna Kedzierska Grazyna Biesiada Andrzej Brzychczy Agnieszka Parnicka Beata Miekinia Aldona Kubisz W?adys?aw Su?owicz 《Polish journal of microbiology》2008,57(1):41-47
The most characteristic finding in non-typhoid salmonella (NTS) infection is acute food related outbreaks of gastroenteritis, which is usually benign and self-limiting. However, more serious extraintestinal findings, such as bacteraemia and focal infections localized to any organ may appear. The objective of this paper is to describe the most important characteristic of the extraintestinal infections due to NTS serotypes observed in University Hospital, in Cracow between January 2000 and December 2006. To do so, we reviewed the clinical presentations, risk groups, complications and outcomes of in-patients, in which extraintestinal non-typhoid Salmonella serotypes were isolated, applying a clinomicrobiological protocol. Out of 30 patients with either bacteraemias (n = 22) or focal salmonella infections (n = 8), 12 had malignancies, 17 had immune dysfunction state, 9 had gastrointestinal disorders and 8 had chronic heart, pulmonary or kidney disease. Four of these patients (13%) who had hematological malignancies (2), renal transplantation (1) and pulmonary disease (1) died. Regarding the clinical picture, primary bacteraemia and focal infections occurred with similar frequency (33.3% and 26.7%, respectively); the remaining were bacteraemias secondary to gastroenteritis. The incidence rate (mean 0.30/1000 hospital admission/year) increased steadily from 0.19/1000 to 0.32/1000 hospital admission during the study period. From 30 Salmonella isolates from extraintestinal samples collected, only four isolates were resistant to ampicillin, ciprofloxacin or trimethoprim-sulfamethoxazole. This finding indicate that multidrug resistance does not represent a serious problem among NTS serotypes collected from the our medical center as monitored over a period of 7 years. Given this presentation, clinicians need to have a high index of suspicion and to consider preemptive therapy, especially in elderly patients who are likely to develop severe immunosuppression following interventions. 相似文献
993.
Ligeza A Wawrzczak-Bargiela A Kaminska D Korostynski M Przewlocki R 《The FEBS journal》2008,275(15):3836-3849
994.
Zofia Stępniewska Weronika Goraj Agnieszka Kuźniar Natalia Łopacka Magdalena Małysza 《Folia microbiologica》2017,62(5):381-391
Aerobic methane-oxidizing bacteria (MOB) are an environmentally significant group of microorganisms due to their role in the global carbon cycle. Research conducted over the past few decades has increased the interest in discovering novel genera of methane-degrading bacteria, which efficiently utilize methane and decrease the global warming effect. Moreover, methanotrophs have more promising applications in environmental bioengineering, biotechnology, and pharmacy. The investigations were undertaken to recognize the variety of endophytic methanotrophic bacteria associated with Carex nigra, Vaccinium oxycoccus, and Eriophorum vaginatum originating from Moszne peatland (East Poland). Methanotrophic bacteria were isolated from plants by adding sterile fragments of different parts of plants (roots and stems) to agar mineral medium (nitrate mineral salts (NMS)) and incubated at different methane values (1–20% CH4). Single colonies were streaked on new NMS agar media and, after incubation, transferred to liquid NMS medium. Bacterial growth dynamics in the culture solution was studied by optical density—OD600 and methane consumption. Changes in the methane concentration during incubation were controlled by the gas chromatography technique. Characterization of methanotrophs was made by fluorescence in situ hybridization (FISH) with Mg705 and Mg84 for type I methanotrophs and Ma450 for type II methanotrophs. Identification of endophytes was performed after 16S ribosomal RNA (rRNA) and mmoX gene amplification. Our study confirmed the presence of both types of methanotrophic bacteria (types I and II) with the predominance of type I methanotrophs. Among cultivable methanotrophs, there were different strains of the genus Methylomonas and Methylosinus. Furthermore, we determined the potential of the examined bacteria for methane oxidation, which ranged from 0.463 ± 0.067 to 5.928 ± 0.169 μmol/L CH4/mL/day. 相似文献
995.
Solanum tuberosum ZPR1 encodes a light‐regulated nuclear DNA‐binding protein adjusting the circadian expression of StBBX24 to light cycle 下载免费PDF全文
Agnieszka Kiełbowicz‐Matuk Jagoda Czarnecka Ewa Banachowicz Pascal Rey Tadeusz Rorat 《Plant, cell & environment》2017,40(3):424-440
ZPR1 proteins belong to the C4‐type of zinc finger coordinators known in animal cells to interact with other proteins and participate in cell growth and proliferation. In contrast, the current knowledge regarding plant ZPR1 proteins is very scarce. Here, we identify a novel potato nuclear factor belonging to this family and named StZPR1. StZPR1 is specifically expressed in photosynthetic organs during the light period, and the ZPR1 protein is located in the nuclear chromatin fraction. From modelling and experimental analyses, we reveal the StZPR1 ability to bind the circadian DNA cis motif ‘CAACAGCATC’, named CIRC and present in the promoter of the clock‐controlled double B‐box StBBX24 gene, the expression of which peaks in the middle of the day. We found that transgenic lines silenced for StZPR1 expression still display a 24 h period for the oscillation of StBBX24 expression but delayed by 4 h towards the night. Importantly, other BBX genes exhibit altered circadian regulation in these lines. Our data demonstrate that StZPR1 allows fitting of the StBBX24 circadian rhythm to the light period and provide evidence that ZPR1 is a novel clock‐associated protein in plants necessary for the accurate rhythmic expression of specific circadian‐regulated genes. 相似文献
996.
Ewa Tomaszewska Piotr Dobrowolski Małgorzata Kwiecień Anna Winiarska-Mieczan Agnieszka Tomczyk Siemowit Muszyński 《Biological trace element research》2017,178(1):54-63
Copper (Cu) is required for all basic biochemical and physiological processes. The objective of this study was to compare the effect of two different chemical forms (sulfates and glycinate chelates also below the recommended dose) of Cu administered to adult rats on the biomechanical and morphometric properties of femur. Male rats at the age of 12 weeks were used in the 12-week experiment. The control diet provided the required Cu level from sulfate (S-Cu), and the other diets were supplemented with Cu-glycine complex. The Cu-Gly-treatment, irrespective of its concentration, did not influence the bone mass and length. The Cu-Gly-treatment in 100 and 75% of daily demand increased mechanical endurance. The Cu-Gly-treatment (regardless of its concentration) increased the real bone volume in epiphysis and decreased the total thickness and zone I of the articular cartilage compared to the control group supplemented with S-Cu. The Cu-Gly-treatment enhanced the content of proteoglycans (except the OG50 group). Dietary Cu given to adult rats in the Cu-Gly complex covering the daily demand in 75% exerted a positive effect on bone metabolism and appeared to be the most effective among the investigated doses of the organic form. 相似文献
997.
Agnieszka Morel Michał Bijak Marta Niwald Elżbieta Miller Joanna Saluk 《Redox report : communications in free radical research》2017,22(6):547-555
Objectives: The objective of the present study was to evaluate oxidative/nitrative stress in the plasma of 50 patients suffering from the secondary progressive course of multiple sclerosis (MS), and to verify its correlation with physical and mental disability as assessed by the Expanded Disability Status Scale (EDSS), and the Beck Depression Inventory (BDI).Methods: Oxidative and nitrative damage to proteins was determined by the level of carbonyl groups and 3-nitrotyrosine using ELISA test. Based on the reaction with Ellman’s reagent, we estimated the concentration of oxidized thiol groups. Additionally, we measured the level of lipid peroxidation.Results: In plasma drawn from MS patients, we observed a significantly higher level of 3-NT (92%; P?0.0003), carbonyl groups (29%; P?0.0001) and thiobarbituric acid reactive substances (73%; P?0.0001), as well as a lower concentration of thiol groups (33%; P?0.0001), in comparison to healthy subjects. We noted positive correlations between the level of carbonyl groups or 3-NT and both diagnostic parameters, EDSS and BDI. Negative correlations were observed between concentration of -SH groups and EDSS and BDI.Conclusion: Our results indicate that impaired red-ox balance can significantly promote neurodegeneration in secondary progressive MS. 相似文献
998.
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1000.
Agnieszka Bukowska-Damska Edyta Reszka Pawel Kaluzny Edyta Wieczorek Monika Przybek Shanbeh Zienolddiny 《Chronobiology international》2017,34(9):1211-1223
Poor sleep quality or sleep restriction is associated with sleepiness and concentration problems. Moreover, chronic sleep restriction may affect metabolism, hormone secretion patterns and inflammatory responses. Limited recent reports suggest a potential link between sleep deprivation and epigenetic effects such as changes in DNA methylation profiles. The aim of the present study was to assess the potential association between poor sleep quality or sleep duration and the levels of 5-methylcytosine in the promoter regions of PER1, PER2, PER3, BMAL1, CLOCK, CRY1 CRY2 and NPAS2 genes, taking into account rotating night work and chronotype as potential confounders or modifiers. A cross-sectional study was conducted on 710 nurses and midwives (347 working on rotating nights and 363 working only during the day) aged 40–60 years. Data from in-person interviews about sleep quality, chronotype and potential confounders were used. Sleep quality and chronotype were assessed using Pittsburgh Sleep Quality Questionnaire (PSQI) and Morningness–Eveningness Questionnaire (MEQ), respectively. Morning blood samples were collected. The methylation status of the circadian rhythm genes was determined via quantitative methylation-specific real-time PCR assays (qMSP) reactions using DNA samples derived from leucocytes. The proportional odds regression model was fitted to quantify the relationship between methylation index (MI) as the dependent variable and sleep quality or sleep duration as the explanatory variable. Analyses were carried out for the total population as well as for subgroups of women stratified by the current system of work (rotating night shift/day work) and chronotype (morning type/intermediate type/evening type). A potential modifying effect of the system of work or the chronotype was examined using the likelihood ratio test. No significant findings were observed in the total study population. Subgroup analyses revealed two statistically significant associations between a shorter sleep duration and 1) methylation level in PER2 among day workers, especially those with the morning chronotype (OR = 2.31, 95%CI:1.24–4.33), and 2) methylation level in CRY2 among subjects with the intermediate chronotype, particularly among day workers (OR = 0.52, 95%CI:0.28–0.96). The study results demonstrated a positive association between average sleep duration of less than 6 hours and the methylation level of PER2 among morning chronotype subjects, and an inverse association for CRY2 among intermediate chronotype subjects, but only among day workers. Both the system of work and the chronotype turned out to be important confounders and modifiers in a number of analyses, making it necessary to consider them as potential covariates in future research on sleep deficiency outcomes. Further studies are warranted to explore this under-investigated topic. 相似文献