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231.
Król E Krejpcio Z Byks H Bogdański P Pupek-Musialik D 《Biological trace element research》2011,143(2):726-737
Chromium(III) is considered as an essential element for carbohydrate and lipid metabolism. The aim of this clinical study
was to evaluate the efficacy of Cr brewer’s yeast supplementation on body mass, carbohydrate, lipids and mineral indices in
type 2 diabetic patients. Twenty adult type 2 diabetic subjects (11 males and 9 females aged 37–63) were supplemented with
Cr brewer’s yeast in dosages of 500 μg Cr/person/day or placebo for 8 weeks in a double-blind, placebo-controlled crossover
design. It was found that supplemental Cr did not affect body mass, blood lipid profile, resistin levels, and the serum and
hair Zn, Fe, and Cu levels, but increased serum Cr (by 116%) and hair Cr (by 20.6%) concentrations and improved some blood
carbohydrate indices (significant increase in the β cell function index by 18.8%) in type 2 diabetic patients. In conclusion,
Cr brewer’s yeast has a weak hypoglycemic potential, but does not affect body mass, blood biochemical profile, and microelement
levels in type 2 diabetic subjects. 相似文献
232.
Anita Wnętrzak Ewelina Lipiec Kazimierz Łątka Wojciech Kwiatek Patrycja Dynarowicz-Łątka 《The Journal of membrane biology》2014,247(7):581-589
The effectiveness of two alkylphosphocholines (APCs), hexadecylphosphocholine (miltefosine) and erucylphosphocholine to combat prostate cancer has been studied in vitro with artificial cancerous membrane, modelled with the Langmuir monolayer technique, and on cell line (Du-145). Studies performed with the Langmuir method indicate that both the investigated drugs have the affinity to the monolayer mimicking prostate cancer membrane (composed of cholesterol:POPC = 0.428) and the drug-membrane interactions are stronger for erucylphosphocholine as compared to hexadecylphosphocholine. Moreover, both studied drugs were found to fluidize the model membrane, which may lead to apoptosis. Indeed, biological studies confirmed that in Du-145 cell line both investigated alkylphosphocholines cause cell death primarily by apoptosis while necrotic cells constitute only a small percentage of APC-treated cells. 相似文献
233.
234.
Szczepanska J Poplawski T Synowiec E Pawlowska E Chojnacki CJ Chojnacki J Blasiak J 《Molecular biology reports》2012,39(2):1561-1574
HEMA (2-hydroxyethyl methacrylate), a methacrylate commonly used in dentistry, was reported to induce genotoxic effects, but
their mechanism is not fully understood. HEMA may be degraded by the oral cavity esterases or through mechanical stress following
the chewing process. Methacrylic acid (MAA) is the primary product of HEMA degradation. In the present work we compared cytotoxic
and genotoxic effects induced by HEMA and MAA in human gingival fibroblasts (HGFs). A 6-h exposure to HEMA or MAA induced
a weak decrease in the viability of HGFs. Neither HEMA nor MAA induced strand breaks in the isolated plasmid DNA, but both
compounds evoked DNA damage in HGFs, as evaluated by the alkaline comet assay. Oxidative modifications to the DNA bases were
monitored by the DNA repair enzymes Endo III and Fpg. DNA damage induced by HEMA and MAA was not persistent and was removed
during a 120 min repair incubation. Results from the neutral comet assay indicated that both compounds induced DNA double
strand breaks (DSBs) and they were confirmed by the γ-H2AX assay. Both compounds induced apoptosis and perturbed the cell
cycle. Therefore, methacrylic acid, a product of HEMA degradation, may be involved in its cytotoxic and genotoxic action. 相似文献
235.
Differential targeting of closely related ECM glycoproteins: the pherophorin family from Volvox. 总被引:2,自引:0,他引:2 下载免费PDF全文
The alga Volvox carteri represents one of the simplest multicellular organisms. Its extracellular matrix (ECM) is modified under developmental control, e.g. under the influence of the sex-inducing pheromone that triggers development of males and females at a concentration below 10(-16) M. A novel ECM glycoprotein (pherophorin-S) synthesized in response to this pheromone was identified and characterized. Although being a typical member of the pherophorins, which are identified by a C-terminal domain with sequence homology to the sex-inducing pheromone, pherophorin-S exhibits a completely novel set of properties. In contrast to the other members of the family, which are found as part of the insoluble ECM structures of the cellular zone, pherophorin-S is targeted to the cell-free interior of the spherical organism and remains in a soluble state. A main structural difference is the presence of a polyhydroxyproline spacer in pherophorin-S that is linked to a saccharide containing a phosphodiester bridge between two arabinose residues. Sequence comparisons indicate that the self-assembling proteins that create the main parts of the complex Volvox ECM have evolved from a common ancestral gene. 相似文献
236.
237.
Dorota?Mańkowska-Wierzbicka Ewelina?Swora-Cwynar Barbara?Poniedzia?ek Zygmunt?Adamski Agnieszka?Dobrowolska Jacek?KarczewskiEmail author 《European cytokine network》2015,26(2):26-37
Introduction
This study aimed to compare the accuracy of selected laboratory markers in assessing disease activity in patients with ulcerative colitis (UC). The analysis included serum IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α, IFN-γ, hsCRP, peripheral regulatory T cells, as well as fecal calprotectin and lactoferrin.Patients and methods
A group of 45 adults with UC was enrolled in the study. Disease activity was assessed using the Mayo endoscopic index, while for clinical activity scoring, the Clinical Activity Index (CAI) was used. Concentrations of markers investigated were estimated by means of flow cytometry and enzyme-linked immunosorbent assays: the results were correlated with both indices.Results
The study demonstrated that both fecal markers, i.e. calprotectin (r = 0.880, P<0.001) and lactoferrin (r = 0.799, P<0.001) correlated closely with the Mayo endoscopic score, and might be used to evaluate the severity of UC in the clinical setting. The correlation of these markers with CAI was also significant, with r = 0.831 for calprotectin (P<0.001) and r = 0.672 for lactoferrin (P<0.05). As for the other markers investigated, only IL-6 (r = 0.598, P<0.001), IL-17A (r = 0.587, P<0.005), and TNF-α (r = 0.701, P<0.001) correlated closely with the Mayo endoscopic index. The correlation of the markers with CAI was also significant, though weaker, with r = 0.525 for IL-6 (P<0.001), r = 0.587 for IL-17A (P<0.05), and r = 0.624 for TNF-α (P<0.001).Discussion
Despite the fact, that UC is generally considered to be an IL-13-driven, Th2-like type of disease, markers of inflammation such as serum interleukin (IL)-6, IL-17, TNF-α, fecal calprotectin and lactoferrin might be useful in assessing disease activity.238.
Kim Le Christopher Tan Huong Le Jasmine Tat Ewelina Zasadzinska Jonathan Diep Ryan Zastrow Chun Chen Jennitte Stevens 《Biotechnology journal》2020,15(1)
During biomanufacturing cell lines development, the generation and screening for single‐cell derived subclones using methods that enable assurance of clonal derivation can be resource‐ and time‐intensive. High‐throughput miniaturization, automation, and analytic strategies are often employed to reduce such bottlenecks. The Beacon platform from Berkeley Lights offers a strategy to eliminate these limitations through culturing, manipulating, and characterizing cells on custom nanofluidic chips via software‐controlled operations. However, explicit demonstration of this technology to provide high assurance of a single cell progenitor has not been reported. Here, a methodology that utilizes the Beacon instrument to ensure high levels of clonality is described. It is demonstrated that the Beacon platform can efficiently generate production cell lines with a superior clonality data package, detailed tracking, and minimal resources. A stringent in‐process quality control strategy is established to enable rapid verification of clonal origin, and the workflow is validated using representative Chinese hamster ovary‐derived cell lines stably expressing either green or red fluorescence protein. Under these conditions, a >99% assurance of clonal origin is achieved, which is comparable to existing imaging‐coupled fluorescence‐activated cell sorting seeding methods. 相似文献
239.
Dorota Skrajnowska Barbara Bobrowska-Korczak Andrzej Tokarz Slawomir Bialek Ewelina Jezierska Justyna Makowska 《Biological trace element research》2013,156(1-3):271-278
In this paper, a hypothesis was assessed whether or not the intoxication with copper and supplementation with copper plus resveratrol would result in changes in the activities of catalase and glutathione peroxidase and moreover if the characteristic changes would appear in concentrations of copper, iron, calcium, magnesium, and zinc in the serum of rats with chemically induced carcinogenesis. Female Sprague-Dawley rats were divided into study groups which, apart from the standard diet, were treated with copper (42.6 mg Cu/kg food as CuSO4·5H2O) or copper plus resveratrol (0.2 mg/kg body) via gavage for a period from 40 days until 20 weeks of age. In cancer groups, the rats were treated with a dose of 80 mg/body weight of 7,12-dimethyl-1,2-benz[a]anthracene (DMBA) given in rapeseed oil at 50 and 80 days of age to induce mammary carcinogenesis. The control groups included the rats kept in the same conditions and fed with the same diet as the animals from the study groups, but not DMBA-treated. The activity of catalase significantly decreased in groups of rats with mammary carcinogenesis that were supplemented with copper (p?<?0.05) or copper plus resveratrol (p?<?0.001) in comparison with the control groups that received the same diets. In cancer groups of nonsupplemented rats, the increase of glutathione peroxidase activity was observed. The process of carcinogenesis and the applied supplementation significantly altered the concentrations of trace elements in serum, in particular as concerns iron and copper. The mean serum iron levels in rats with breast cancer were significantly lower than those in the control groups (p?<?0.001). The mean serum copper levels significantly decreased in the groups of rats with mammary carcinogenesis that were supplemented with copper or copper plus resveratrol in comparison with the control groups that received the same diets (p?<?0.001). The characteristic changes in iron content and the zinc/copper and zinc/iron ratios in blood may be used as one of the prognostic factors in breast cancer research. 相似文献