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541.
Musilek K Holas O Kuca K Jun D Dohnal V Dolezal M 《Bioorganic & medicinal chemistry letters》2006,16(21):5673-5676
Three asymmetrical AChE reactivators with cyano-moiety and propane linker were synthesized using modification of currently known synthetic pathways. Their potency to reactivate AChE inhibited by nerve agent tabun and insecticide paraoxon was tested in vitro and compared to pralidoxime, HI-6, obidoxime, K027, and K048. According to the results, three compounds seem to be promising against paraoxon-inhibited AChE. Better results were obtained for bisquaternary substances at least with one oxime group in position four. None of tested substances was able to satisfactorily reactivate tabun-inhibited AChE at concentration applicable for in vivo experiments. 相似文献
542.
Aleksandra Klemba Magdalena Kowalewska Wojciech Kukwa Katarzyna Tonska Aleksandra Szybinska Malgorzata Mossakowska Anna Scinska Paweł Golik Kamil Koper Jakub Radziszewski Andrzej Kukwa Anna M Czarnecka Ewa Bartnik 《Journal of biomedical science》2010,17(1):1-15
Vulvar squamous cell carcinoma (VSCC) is a rare female genital neoplasm. Although numerous molecular changes have been reported in VSCC, biomarkers of clinical relevance are still lacking. On the other hand, there is emerging evidence on the use of mtDNA as a diagnostic tool in oncology. In order to investigate mtDNA status in VSCC patients, haplogroup distribution analysis and D-loop sequencing were performed. The results were compared with available data for the general Polish population, cancer free-centenarians as well as patients with endometrial and head and neck cancer. The obtained data were also compared with the current status of mitochondrial databases. Significant differences in haplogroup distribution between VSCC cohort, general Polish population and cancer-free centenarians cohort were found. Moreover, a correlation between the VSCC patients haplogroup and HPV status was observed. Finally, a specific pattern of mtDNA polymorphisms was found in VSCC. Our results suggest that the mitochondrial genetic background may influence the risk of VSCC occurrence as well as susceptibility to HPV infection. 相似文献
543.
Mark A. Brooks Kamil Gewartowski Eirini Mitsiki Juliette Létoquart Roland A. Pache Ysaline Billier Michela Bertero Margot Corréa Mariusz Czarnocki-Cieciura Michal Dadlez Véronique Henriot Noureddine Lazar Lila Delbos Dorothée Lebert Jan Piwowarski Pascal Rochaix Bettina Böttcher Luis Serrano Bertrand Séraphin Herman van Tilbeurgh Andrzej Dziembowski 《Structure (London, England : 1993)》2010,18(9):1075-1082
544.
545.
Monika M. Kaczmarek Kamil Krawczynski Jolanta Kiewisz Adam J. Ziecik 《Theriogenology》2010,74(7):1207-1220
Seminal fluids introduced to the female reproductive tract at mating can affect subsequent events, such as ovulation, fertilization, conception, and pregnancy. Bioactive molecules present in seminal plasma can modify the cellular composition, structure, and function of local tissues and of tissues distal to the tract. The oviduct plays a decisive role in reproduction providing a beneficial milieu for gamete maturation, fertilization, and early embryonic development. Therefore we have investigated whether intrauterine infusion of seminal plasma can modulate prostaglandin (PG) synthesis in the porcine oviduct through regulation of gene and protein expression of enzymes of prostaglandin synthesis pathway. Among several enzymes involved in the prostaglandin synthesis pathway tested in the present study PGF2α synthase (PTGFS) and prostaglandin 9-ketoreductase (CBR1), which convert PGE2 to PGF2α, expression were significantly down-regulated in the oviducts on Day 1 after seminal plasma infusion into the uterine horns. The effects of the treatment were transient and by Day 5 levels of PTGFS and CBR1 were comparable in seminal plasma-treated and control animals. Additionally, increased PGE2 to PGF2α and PGFM to PGF2α ratios in the oviductal tissues were indicated. Our results clearly demonstrate that seminal plasma affects prostaglandin synthesis in the porcine oviduct. Altered PTGFS and CBR1 expression in consequence changed PGE2 to PGF2α and PGFM to PGF2α ratios in the porcine oviduct. 相似文献
546.
Roman J. Szczesny Lukasz S. Borowski Lien K. Brzezniak Aleksandra Dmochowska Kamil Gewartowski Ewa Bartnik Piotr P. Stepien 《Nucleic acids research》2010,38(1):279-298
The mechanism of human mitochondrial RNA turnover and surveillance is still a matter of debate. We have obtained a cellular model for studying the role of hSuv3p helicase in human mitochondria. Expression of a dominant-negative mutant of the hSUV3 gene which encodes a protein with no ATPase or helicase activity results in perturbations of mtRNA metabolism and enables to study the processing and degradation intermediates which otherwise are difficult to detect because of their short half-lives. The hSuv3p activity was found to be necessary in the regulation of stability of mature, properly formed mRNAs and for removal of the noncoding processing intermediates transcribed from both H and L-strands, including mirror RNAs which represent antisense RNAs transcribed from the opposite DNA strand. Lack of hSuv3p function also resulted in accumulation of aberrant RNA species, molecules with extended poly(A) tails and degradation intermediates truncated predominantly at their 3′-ends. Moreover, we present data indicating that hSuv3p co-purifies with PNPase; this may suggest participation of both proteins in mtRNA metabolism. 相似文献
547.
Russell P. Balda Alan C. Kamil Peter A. Bednekoff Arla G. Hile 《Ethology : formerly Zeitschrift fur Tierpsychologie》1997,103(1):47-55
Three species of seed-caching corvids were tested in a spatial, three-dimensional analog of the radial maze. The apparatus consisted of five artificial trees, each with six branches. A wooden feeder could be attached to each branch. Each feeder contained a hole that could hold a pine seed. During the first 40 trials of acquisition testing, all three species improved rapidly with nutcrackers and pinyon jays performing at higher levels than scrub jays. Testing was then interrupted for 31 d. After the interruption, the two species of jays continued to improve but the nutcrackers did not. This species performed with only modest accuracy through the remainder of the experiment. Mixed-interval testing was done at 10, 60, 180, and 300 min. All species declined in accuracy with increased retention interval. However, at 10 and 180 min, pinyon jays performed significantly better than scrub jays. This is the fourth spatial memory task in which pinyon jays have out-performed scrub jays. The difference in performance between these two species provides more evidence for divergence in spatial cognition as a function of dependence on cached food. 相似文献
548.
549.
Büşra Korkmaz Gülin Renda Gözde Bozdal Kamil Coşkunçelebi Arif Bozdeveci Ugur Uzuner Nurettin Yaylı 《化学与生物多样性》2023,20(4):e202201052
Five new phenyl dihydroisocoumarin glycosides ( 1 – 5 ) and two known compounds ( 6 – 7 ) were identified from the butanol fraction of Scorzonera longiana. The structures of 1 – 7 were elucidated based on spectroscopic methods. Antimicrobial, antitubercular, and antifungal evaluation of compounds 1 – 7 were carried out using the microdilution method against nine microorganisms. Compound 1 was active only against Mycobacterium smegmatis (Ms) with a MIC value of 14.84 μg/mL. All tested compounds ( 1 – 7 ) were active against Ms but only compounds 3–7 were active against fungi (C. albicans, S. cerevisiae) with MIC values of 25.0–125 μg/mL. In addition, molecular docking studies were conducted against Ms DprE1 (PDB ID: 4F4Q), Mycobacterium tuberculosis (Mbt) DprE1 (PDB ID: 6HEZ), and arabinosyltransferase C (EmbC, PDB ID: 7BVE) enzymes. Compounds 2 , 5 , and 7 are the most effective Ms 4F4Q inhibitors. Compound 4 was the most promising inhibitory activity on Mbt DprE with the lowest binding energy of −9,9 kcal/mol. 相似文献
550.
Wojciech Szczeklik Yannick LeManach Jakub Fronczek Kamil Polok David Conen Finlay A. McAlister Sadeesh Srinathan Pablo Alonso-Coello Bruce Biccard Emmanuelle Duceppe Diane Heels-Ansdell Jacek Grka Shirley Pettit Pavel S. Roshanov P.J. Devereaux 《CMAJ》2020,192(49):E1715
BACKGROUND:Postoperative atrial fibrillation (POAF) is associated with clinically significant short- and long-term complications after noncardiac surgery. Our aim was to describe the incidence of clinically important POAF after noncardiac surgery and establish the prognostic value of N-terminal pro–brain-type natriuretic peptide (NT-proBNP) in this context.METHODS:The Vascular events In noncardiac Surgery patIents cOhort evaluatioN (VISION) Study was a prospective cohort study involving patients aged 45 years and older who had inpatient noncardiac surgery that was performed between August 2007 and November 2013. We determined 30-day incidence of clinically important POAF (i.e., resulting in angina, congestive heart failure, symptomatic hypotension or requiring treatment) using logistic regression models to analyze the association between preoperative NT-proBNP and POAF.RESULTS:In 37 664 patients with no history of atrial fibrillation, we found that the incidence of POAF was 1.0% (95% confidence interval [CI] 0.9%–1.1%; 369 events); 3.2% (95% CI 2.3%–4.4%) in patients undergoing major thoracic surgery, 1.3% (95% CI 1.2%–1.5%) in patients undergoing major nonthoracic surgery and 0.2% (95% CI 0.1%–0.3%) in patients undergoing low-risk surgery. In a subgroup of 9789 patients with preoperative NT-proBNP measurements, the biomarker improved the prediction of POAF risk over conventional prognostic factors (likelihood ratio test p < 0.001; fraction of new information from NT-proBNP was 16%). Compared with a reference NT-proBNP measurement set at 100 ng/L, adjusted odds ratios for the occurrence of POAF were 1.31 (95% CI 1.15–1.49) at 200 ng/L, 2.07 (95% CI 1.27–3.36) at 1500 ng/L and 2.39 (95% CI 1.26–4.51) at 3000 ng/L.INTERPRETATION:We determined that the incidence of clinically important POAF after noncardiac surgery was 1.0%. We also found that preoperative NT-proBNP levels were associated with POAF independent of established prognostic factors. Trial registration: ClinicalTrials.gov, no. Postoperative atrial fibrillation (POAF) is the most common arrhythmia that occurs after noncardiac surgery NCT005121091 and is associated with prolonged hospital stays and an increased risk of stroke and death,2–8 both of which raise societal costs.9 The reported incidence of POAF ranges from 3.7% to 21.0% in patients undergoing thoracic surgery3,10 and from less than 0.5% to 10.0% in patients undergoing noncardiac, nonthoracic surgery (Appendix 1, Supplementary Table 1, available at www.cmaj.ca/lookup/doi/10.1503/cmaj.200840/tab-related-content).6,11Brain-type natriuretic peptide (BNP) is a neurohormone released by cardiomyocytes in response to volume and pressure overload.12 This biomarker has an established role in the diagnosis and management of heart failure and in predicting cardiovascular morbidity and mortality.13 Although natriuretic peptides have been shown to predict new-onset atrial fibrillation (AF) in the nonsurgical setting reliably,14–18 their value in predicting POAF after noncardiac surgery is unclear.19–21The Vascular events In non-cardiac Surgery patIents cOhort evaluatioN (VISION) Study was a prospective international cohort study involving a representative sample of adults who underwent noncardiac surgery that required an overnight hospital stay. One of the predefined objectives in VISION was to determine the incidence of new-onset, clinically important POAF. We aimed to describe the overall and surgery-specific incidence of POAF after noncardiac surgery and to investigate the association between preoperative N-terminal pro–brain-type natriuretic peptide (NT-proBNP) and POAF. We hypothesized that measurement of NT-proBNP would improve POAF risk prediction beyond conventional prognostic factors. 相似文献