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排序方式: 共有270条查询结果,搜索用时 15 毫秒
1.
Anna Ciechanowska Ilona M. Gora Stanislawa Sabalinska Piotr Ladyzynski 《International journal of molecular sciences》2022,23(12)
Diabetes mellitus causes endothelial dysfunction. The aim of this study was to investigate the effect of normal (5 mmol/L), high (20 mmol/L), and fluctuating (5 and 20 mmol/L changed every day) glucose concentration in the culture medium on the viability of human umbilical vein endothelial cells (HUVECs) co-cultured with human umbilical artery smooth muscle cells (HUASMCs). The cultures were conducted on semi-permeable flat polysulfone (PSU) fibronectin-coated membranes immobilized in self-made inserts. The insert contained either HUVECs on a single membrane or HUASMCs and HUVECs on two membranes close to each other. Cultures were conducted for 7 or 14 days. Apoptosis, mitochondrial potential, and the production of reactive oxygen species and lactate by HUVECs were investigated. The results indicate that fluctuations in glucose concentration have a stronger negative effect on HUVECs viability than constant high glucose concentration. High and fluctuating glucose concentrations slow down cell proliferation compared to the culture carried out in the medium with normal glucose concentration. In conclusion, HUASMCs affect the viability of HUVECs when both types of cells are co-cultured in medium with normal or variable glucose concentration. 相似文献
2.
Zsfia Ilona Szojka Sara Karlson Emil Johansson Gülen
zkaya ahin Marianne Jansson 《International journal of molecular sciences》2022,23(9)
HIV-2, compared to HIV-1, elicits potent and broadly neutralizing antibodies, and uses a broad range of co-receptors. However, both sensitivity to neutralization and breadth of co-receptor use varies between HIV-2 isolates, and the molecular background is still not fully understood. Thus, in the current study, we have deciphered relationships between HIV-2 neutralization sensitivity, co-receptor use and viral envelope glycoprotein (Env) molecular motifs. A panel of primary HIV-2 isolates, with predefined use of co-receptors, was assessed for neutralization sensitivity using a set of HIV-2 Env-directed monoclonal antibodies and co-receptor indicator cell lines. Neutralization sensitivity of the isolates was analysed in relation target cell co-receptor expression, in addition to amino acid motifs and predicted structures of Env regions. Results showed that HIV-2 isolates were more resistant to neutralizing antibodies when entering target cells via the alternative co-receptor GPR15, as compared to CCR5. A similar pattern was noted for isolates using the alternative co-receptor CXCR6. Sensitivity to neutralizing antibodies appeared also to be linked to specific Env motifs in V1/V2 and C3 regions. Our findings suggest that HIV-2 sensitivity to neutralization depends both on which co-receptor is used for cell entry and on specific Env motifs. This study highlights the multifactorial mechanisms behind HIV-2 neutralization sensitivity. 相似文献
3.
Statistically designed experiments have been made on partially carboxymethylated cotton fabric. The effect of the reaction parameters (concentration of sodium hydroxide and mono-chioroacetic acid and period of time) on the crystallinity (measured by x-ray diffraction), on the iodine sorption and on the disorder of amorphous fraction (calculated from iodine sorption capacity) are presented by polynomial models. © 1996 John Wiley & Sons, Inc. 相似文献
4.
5.
The Effect of processing on the content and composition of free sterols and sterol esters in soybean oil 总被引:1,自引:0,他引:1
The content and composition of free sterols and sterol esters in crude soybean oil and in oils from different stages of two
continuous refining systems were determined. The sterols were isolated by preparative thin layer chromatography and analyzed
by gas chromatography with cholesterol as an internal standard. The free sterols in one of the degummed oils amounted to 3.1
mg/g and were diminished to 1.8 mg/g oil by the De Laval Short-Mix refining process. The content of free sterols of the other
degummed oil was reduced from 3.4 to 1.6 mg/g oil by the Zenith process. The greatest reduction of sterol content was caused
by the treatment with bleaching earth. The sterol esters accounted for 0.6 mg/g of the degummed oil, and only very small changes
were observed during the processes. However, changes in the composition of fatty acids of the sterol esters were found. These
changes might indicate a selective deacylation of sterol esters or an interesterification during the refining processes. The
composition of sterols in free and esterified form were different. Campesterol, stigmasterol and sitosterol were obtained
in both free and esterified form, but Δ7 stigmasterol was only found in esterified form. Only small changes in the percentage
distribution of the sterols occurred during the processes.
Present adress Food Technology Division, ALFA-LAVAL,S-14700 Tumba, Sweden 相似文献
6.
7.
Ilona Hromadnikova Katerina Kotlabova Ladislav Krofta 《International journal of molecular sciences》2022,23(7)
The aim of the study was to determine if aberrant expression profile of cardiovascular disease associated microRNAs would be able to predict within 10 to 13 weeks of gestation preterm delivery such as spontaneous preterm birth (PTB) or preterm prelabor rupture of membranes (PPROM) in the absence of other pregnancy-related complications (gestational hypertension, preeclampsia, fetal growth restriction, or small for gestational age). In addition, we assessed if aberrant expression profile of cardiovascular disease associated microRNAs would be able to predict preterm delivery before and after 34 weeks of gestation. The retrospective study was performed within the period November 2012 to March 2020. Whole peripheral blood samples were collected from 6440 Caucasian individuals involving 41 PTB and 65 PPROM singleton pregnancies. A control group, 80 singleton term pregnancies, was selected on the base of equal sample storage time. Gene expression of 29 selected cardiovascular disease associated microRNAs was studied using real-time RT-PCR. Downregulation of miR-16-5p, miR-20b-5p, miR-21-5p, miR-24-3p, miR-26a-5p, miR-92a-3p, miR-126-3p, miR-133a-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-210-3p, miR-221-3p and miR-342-3p was observed in pregnancies with preterm delivery before 37 (≤36 + 6/7) weeks of gestation. Majority of downregulated microRNAs (miR-16-5p, miR-24-3p, miR-26a-5p, miR-92a-3p, miR-133a-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-210-3p, and miR-342-3p) was associated with preterm delivery occurring before 37 (≤36 + 6/7) weeks of gestation. The only miR-210-3p was downregulated in pregnancies with preterm delivery before 34 (≤33 + 6/7) weeks of gestation. The type of preterm delivery also had impact on microRNA gene expression profile. Downregulation of miR-24-3p, miR-92a-3p, miR-155-5p, and miR-210-3p was a common feature of PTB and PPROM pregnancies. Downregulation of miR-16-5p, miR-20b-5p, miR-26a-5p, miR-126-3p, miR-133a-3p, miR-146a-5p, miR-221-3p, and miR-342-3p appeared just in PTB pregnancies. No microRNA was uniquely dysregulated in PPROM pregnancies. The combination of 12 microRNAs (miR-16-5p, miR-20b-5p, miR-21-5p, miR-24-3p, miR-26a-5p, miR-92a-3p, miR-133a-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-210-3p, and miR-342-3p, AUC 0.818, p < 0.001, 74.53% sensitivity, 75.00% specificity, cut off > 0.634) equally as the combination of 6 microRNAs (miR-16-5p, miR-21-5p, miR-24-3p, miR-133a-3p, miR-155-5p, and miR-210-3p, AUC 0.812, p < 0.001, 70.75% sensitivity, 78.75% specificity, cut off > 0.652) can predict preterm delivery before 37 weeks of gestation in early stages of gestation in 52.83% pregnancies at 10.0% FPR. Cardiovascular disease associated microRNAs represent promising biomarkers with very good diagnostical potential to be implemented into the current routine first trimester screening programme to predict preterm delivery. 相似文献
8.
Jekaterina Hermane Ilona Bułyszko Dr. Simone Eichner Dr. Florenz Sasse Wera Collisi Prof. Dr. Antti Poso Emilia Schax Dr. Johanna‐Gabriela Walter Prof. Dr. Thomas Scheper Dr. Klaus Kock Prof. Dr. Christian Herrmann Dr. Pooyan Aliuos Prof. Dr. Günter Reuter Priv.‐Doz. Dr. Carsten Zeilinger Prof. Dr. Andreas Kirschning 《Chembiochem : a European journal of chemical biology》2015,16(2):302-311
Streptomyces hygroscopicus is a natural producer of geldanamycin. Mutasynthetic supplementation of an AHBA‐blocked mutant with all possible monofluoro 3‐aminobenzoic acids provided new fluorogeldanamycins. These showed strong antiproliferative activity and inhibitory effects on human heat shock protein Hsp90. Binding to Hsp90 in the low nanomolar range was determined from molecular modelling, AFM analysis and by calorimetric studies. 相似文献
9.
Nicki Frederiksen Assoc. Prof. Paul R. Hansen Dr. Dorota Zabicka Magdalena Tomczak Malgorzata Urbas Dr. Ilona Domraceva Prof. Fredrik Björkling Assoc. Prof. Henrik Franzyk 《ChemMedChem》2020,15(24):2544-2561
The influence of hydrophobicity on antibacterial activity versus the effect on the viability of mammalian cells for peptide/peptoid hybrids was examined for oligomers based on the cationic Lys-like peptoid residue combined with each of 28 hydrophobic amino acids in an alternating sequence. Their relative hydrophobicity was correlated to activity against both Gram-negative and Gram-positive species, human red blood cells, and HepG2 cells. This identified hydrophobic side chains that confer potent antibacterial activity (e. g., MICs of 2–8 μg/mL against E. coli) and low toxicity toward mammalian cells (<10 % hemolysis at 400 μg/mL and IC50>800 μg/mL for HepG2 viability). Most peptidomimetics retained activity against drug-resistant strains. These findings corroborate the hypothesis that for related peptidomimetics two hydrophobicity thresholds may be identified: i) it should exceed a certain level in order to confer antibacterial activity, and ii) there is an upper limit, beyond which cell selectivity is lost. It is envisioned that once identified for a given subclass of peptide-like antibacterials such thresholds can guide further optimisation. 相似文献
10.
Low temperature sintering of barium titanate ceramics assisted by addition of lithium fluoride-containing sintering additives 总被引:1,自引:0,他引:1
Hamid Naghib-zadeh Carsten Glitzky Ilona Drfel Torsten Rabe 《Journal of the European Ceramic Society》2010,30(1):81-86
By addition of LiF-containing sintering additives to commercial BaTiO3 powder, more than 98% of the theoretical density was reached at a sintering temperature of 900 °C both on powder compacts and laminates. Dielectric measurements were performed on ceramic samples in the temperature and frequency ranges from −20 °C to 125 °C and from 103 to 106 Hz, respectively. High relative permittivity (r 3160) and low dielectric loss (tan δ 0.014) were measured for tapes of the favoured material. The breakdown strength for tapes with a thickness of about 80 μm is 30 kV/mm. The microprobe analysis showed, that no interfacial reaction between the dielectric layer and the Ag-electrode had occurred.The newly developed barium titanate ceramics completely densifying at 900 °C turned out to be promising for integration of buried capacitors in LTCC multilayers. 相似文献