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981.
982.
Długosz Angelika Drogosz Joanna Deredas Dariusz Janecki Tomasz Janecka Anna 《Molecular biology reports》2018,45(5):1187-1195
Molecular Biology Reports - Coumarin is a plant-derived compound but as such has no medical uses. Several synthetic coumarin analogs have been shown to possess anti-proliferative activity and to... 相似文献
983.
Distinctive inhibition of alkaline phosphatase isozymes by thiazol‐2‐ylidene‐benzamide derivatives: Functional insights into their anticancer role 下载免费PDF全文
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Magdalena Wypij Joanna Czarnecka Magdalena Świecimska Hanna Dahm Mahendra Rai Patrycja Golinska 《World journal of microbiology & biotechnology》2018,34(2):23
We report synthesis of silver nanoparticles (AgNPs) from Streptomyces xinghaiensis OF1 strain, which were characterised by UV–Vis and Fourier transform infrared spectroscopy, Zeta sizer, Nano tracking analyser, and Transmission electron microscopy. The antimicrobial activity of AgNPs alone, and in combination with antibiotics was evaluated against bacteria, namely Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis, and yeasts viz., Candida albicans and Malassezia furfur by using micro-dilution method. The minimum inhibitory concentration (MIC) and minimum biocidal concentration of AgNPs against bacterial and yeast strains were determined. Synergistic effect of AgNPs in combination with antibacterial and antifungal antibiotics was determined by FIC index. In addition, MTT assay was performed to study cytotoxicity of AgNPs alone and in combination with antibiotics against mouse fibroblasts and HeLa cell line. Biogenic AgNPs were stable, spherical, small, polydispersed and capped with organic compounds. The variable antimicrobial activity of AgNPs was observed against tested bacteria and yeasts. The lowest MIC (16 µg ml?1) of AgNPs was found against P. aeruginosa, followed by C. albicans and M. furfur (both 32 µg ml?1), B. subtilis and E. coli (both 64 µg ml?1), and then S. aureus and Klebsiella pneumoniae (256 µg ml?1). The high synergistic effect of antibiotics in combination with AgNPs against tested strains was found. The in vitro cytotoxicity of AgNPs against mouse fibroblasts and cancer HeLa cell lines revealed a dose dependent potential. The IC50 value of AgNPs was found in concentrations of 4 and 3.8 µg ml?1, respectively. Combination of AgNPs and antibiotics significantly decreased concentrations of both antimicrobials used and retained their high antibacterial and antifungal activity. The synthesis of AgNPs using S. xinghaiensis OF1 strain is an eco-friendly, cheap and nontoxic method. The antimicrobial activity of AgNPs could result from their small size. Remarkable synergistic effect of antibiotics and AgNPs offer their valuable potential in nanomedicine for clinical application as a combined therapy in the future. 相似文献
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Adam Mieczkowski Mateusz Psurski Maciej Bagiński Bartosz Bieszczad Magdalena Mroczkowska Marcin Wilczek Joanna Czajkowska Damian Trzybiński Krzysztof Woźniak Joanna Wietrzyk 《Bioorganic & medicinal chemistry letters》2018,28(4):618-625
A series of optically pure (R)- and (S)-1,3,4,12a-tetrahydropyrazino[2,1-c][1,4]benzodiazepine-6,12(2H,11H)-dione derivatives was designed and synthesized as novel anthramycin analogues in a three-step, one-pot procedure, and tested for their antiproliferative activity on nine following cell lines: MV-4-11, UMUC-3, MDA-MB-231, MCF7, LoVo, HT-29, A-549, A2780 and BALB/3T3. The key structural features responsible for exhibition of cytotoxic effect were determined: the (S)-configuration of chiral center and the presence of hydrophobic 4-biphenyl substituent in the side chain. Introduction of bromine atom into the 8 position (8g) or substitution of dilactam ring with benzyl group (8m) further improved the activity and selectivity of investigated compounds. Among others, compound 8g exhibited selective cytotoxic effect against MV-4-11 (IC50?=?8.7?μM) and HT-29 (IC50?=?17.8?μM) cell lines, while 8m showed noticeable anticancer activity against MV-4-11 (IC50?=?10.8?μM) and LoVo (IC50?=?11.0?μM) cell lines. The cell cycle arrest in G1/S checkpoint and apoptosis associated with overproduction of reactive oxygen species was also observed for 8e and 8m. 相似文献
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Rafał Kocyłowski Iwona Lewicka Mariusz Grzesiak Zuzanna Gaj Przemysław Oszukowski Constantin von Kaisenberg Joanna Suliburska 《Biological trace element research》2018,182(2):217-223
The mineral levels in maternal serum change during pregnancy and may be correlated with those of newborn cord blood. The aim of this study was to evaluate the concentrations of calcium (Ca), magnesium (Mg), zinc (Zn), iron (Fe), and copper (Cu) in maternal blood before and after delivery and in umbilical cord vein and artery serum. The study was carried out in 64 Caucasian pregnant women who delivered in a district hospital in Greater Poland region, aged 28.1 ± 5.4 years, with a mean gestational age of 39.2 ± 1.3 weeks. Blood samples were taken from women 2–8 h before delivery and immediately after childbirth. The umbilical cord artery and vein blood of newborns was obtained immediately after childbirth. The levels of minerals in serum were determined by flame atomic absorption spectrometry. A significant drop in the concentrations of Mg (17.71 ± 1.51 vs 17.07 ± 1.61 μg/ml; p < 0.007), Fe (1.08 ± 0.46 vs 0.82 ± 0.35 μg/ml; p < 0.0004), and Zn (0.63 ± 0.17 vs 0.46 ± 0.16; p < 0.0001) in maternal serum was found after delivery. Moreover, higher levels of Ca, Fe, and Zn and lower levels of Cu were observed in the umbilical vein (Ca: 102.80 ± 7.80 μg/ml; p < 0.0001, Fe: 1.96 ± 0.43 μg/ml; p < 0.0001, Zn: 0.65 ± 0.16 μg/ml; p < 0.0001, Cu: 0.36 ± 0.09 μg/ml; p < 0.0001) and in the umbilical artery cord blood (Ca: 98.07 ± 8.18 μg/ml; p < 0.0001, Fe: 1.63 ± 0.30 μg/ml; p < 0.0001, Zn: 0.65 ± 0.15 μg/ml; p < 0.0001, and Cu: 0.36 ± 0.10 μg/ml; p < 0.0001) compared to the maternal serum (Ca: 85.05 ± 10.76 μg/ml, Fe: 0.82 ± 0.35 μg/ml, Zn: 0.46 ± 0.16 μg/ml, and Cu: 1.90 ± 0.35 μg/ml). Fe levels in the cord artery serum negatively correlated with blood loss during delivery (R = ?0.48; p = 0.01), while the Ca concentration in the maternal serum after birth decreased with the age of the women (R = ?0.25; p = 0.03). In conclusion, it seems that the process of birth alters the mineral levels in pregnant women’s blood. Moreover, it was found that blood loss and the age of the mother are associated with mineral concentrations in the maternal serum and cord artery blood. 相似文献
989.
Human influence on the environment is evident at all landscape and ecological scales, from local to global, shaping both abiotic and biotic processes. Niche construction theory provides a means by which to investigate the consequences of these anthropogenic effects, but primatological research has been slow to integrate ecological and evolutionary timelines. We review methods that can be used to study how human niche construction influences nonhuman primates including phenological assessment, nonhuman primate behavioral observations, and ethnographic interview techniques. We argue that this approach provides a starting place to examine niche construction theory but that scholars of primate behavioral ecology must expand our methodologies to bridge the disconnect between ecological and evolutionary research time frames. We suggest areas of research and methods that have been underused but offer opportunities for integrative, innovative research. We conclude that an integrated, synthetic methodological approach is a major goal and that it will likely require a cross-disciplinary, collaborative effort. 相似文献
990.
Yulin Ren Gerardo D. Anaya-Eugenio Austin A. Czarnecki Tran Ngoc Ninh Chunhua Yuan Hee-Byung Chai Djaja D. Soejarto Joanna E. Burdette Esperanza J. Carcache de Blanco A. Douglas Kinghorn 《Bioorganic & medicinal chemistry》2018,26(15):4452-4460
Syzygium is a large genus of flowering plants, with several species, including the clove tree, used as important resources in the food and pharmaceutical industries. In our continuing search for anticancer agents from higher plants, a chloroform extract of the leaves and twigs of Syzygium corticosum collected in Vietnam was found to be active toward the HT-29 human colon cancer cell line. Separation of this extract guided by HT-29 cells and nuclear factor-kappa B (NF-κB) inhibition yielded 19 known natural products, including seven triterpenoids, three ellagic acid derivatives, two methylated flavonoids, a cyclohexanone, four megastigmanes, a small lactone, and an aromatic aldehyde. The full stereochemistry of (+)-fouquierol (2) was defined for the first time. Biological investigations showed that (+)-ursolic acid (1) is the major cytotoxic component of S. corticosum, which exhibited also potent activities in the NF-κB and mitochondrial transmembrane potential (MTP) inhibition assays conducted, with IC50 values of 31?nM and 3.5?µM, respectively. Several analogues of (+)-ursolic acid (1) were synthesized, and a preliminary structure-activity relationship (SAR) study indicated that the C-3 hydroxy and C-28 carboxylic acid groups and 19,20-dimethyl substitution are all essential in the mediation of the bioactivities observed for this triterpenoid. 相似文献