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排序方式: 共有179条查询结果,搜索用时 15 毫秒
61.
Kamila Puppel Jan Slsarz Grzegorz Grodkowski Pawe Solarczyk Piotr Kostusiak Magorzata Kunowska-Slsarz Kinga Grodkowska Anna Zalewska Beata Kuczyska Marcin Gobiewski 《International journal of molecular sciences》2022,23(17)
Enzymatic diagnostics have practical applications in diseases of the liver, heart, pancreas, muscles, blood, and neoplastic diseases. This study aimed to compare enzyme activity to describe dairy cows’ metabolism during early lactation. Based on their general health symptoms, the cows were assigned to one of three groups: acidotic, healthy and ketotic. Samples of milk, blood and rumen fluid were collected at 12 ± 5 days postpartum. Ketotic cows were characterized by the highest malondialdehyde (MDA, 76.098 nM/mL), glutathione reductase (GluRed, 109.852 U/L), superoxide dismutase (SOD, 294.22 U/L) and gamma-glutamyltranspeptidase (GGTP, 71.175 U/L) activity. In comparing ketotic and acidotic cows, MDA, GluRed, SOD and GGTP activity were higher by a factor of almost: 1.85, 1.89, 0.79 and 2.50, respectively. Acidotic cows were characterized by the highest aspartate aminotransferase activity (AspAT, 125.914 U/L). In comparing acidotic and ketotic cows, AspAT activity was higher by a factor of almost 1.90. The use of enzymatic markers could limit the frequency of sampling for laboratory analyses and may result in a faster diagnosis of metabolic disorders. AspAT activity in blood serum seems to be a good indicator of acidosis; GGTP may participate in the pathogenesis of ketosis. 相似文献
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Aleksandra Kupliska Kamila Rzd Marek Wojciechowski Sawomir Milewski Iwona Gabriel 《International journal of molecular sciences》2022,23(14)
Due to the apparent similarity of fungal and mammalian metabolic pathways, the number of established antifungal targets is low, and the identification of novel ones is highly desirable. The results of our studies, presented in this work, indicate that the fungal biosynthetic pathway of L-methionine, an amino acid essential for humans, seems to be an attractive perspective. The MET2 gene from Candida albicans encoding L-homoserine O-acetyltransferase (CaMet2p), an enzyme catalyzing the first step in that pathway, was cloned and expressed as the native or the oligo-His-tagged fusion protein in Escherichia coli. The recombinant enzymes were purified and characterized for their basic molecular properties and substrate specificities. The purified MET2 gene product revealed the appropriate activity, catalyzed the conversion of L-homoserine (L-Hom) to O-acetyl-L-homoserine (OALH), and exhibited differential sensitivity to several L-Hom or OALH analogues, including penicillamine. Surprisingly, both penicillamine enantiomers (L- and D-Pen) displayed comparable inhibitory effects. The results of the docking of L- and D-Pen to the model of CaMet2p confirmed that both enantiomeric forms of the inhibitor are able to bind to the catalytic site of the enzyme with similar affinities and a similar binding mode. The sensitivity of some fungal cells to L-Pen, depending on the presence or absence of L-Met in the medium, clearly indicate Met2p targeting. Moreover, C. glabrata clinical strains that are resistant to fluconazole displayed a similar susceptibility to L-Pen as the wild-type strains. Our results prove the potential usefulness of Met2p as a molecular target for antifungal chemotherapy. 相似文献
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Kamila Żelechowska Diana Sobota Bartłomiej Cieślik Marta Prześniak-Welenc Marcin Łapiński Jan F. Biernat 《Fullerenes, Nanotubes and Carbon Nanostructures》2018,26(5):269-277
Effective, one-pot method of CNTs phosphonylation is presented. Cheap and readily available reagents are used, so the process can be easily transferred to large-scale production. The product was analyzed using spectroscopic methods (FTIR, UV-vis, XPS). Thermal properties of the bis-phosphonated nanotubes are reported for the first time. Newly obtained material was tested as an adsorbent for mercury removal from water. The sorption capacity for newly developed adsorbent was as high as 223.7 mg/g. The adsorption kinetics were studied within framework of Lagergren model, and Langmuir and Freundlich isotherms have been described. The effect of pH on the adsorption process has been evaluated and the optimal environmental conditions were determined to be neutral. The presence of bivalent ions Cd2+, Ni2+ in the solution did not affect adsorption efficiency of novel materials. 相似文献
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Computer‐assisted instruction can change the way introductory statistics and quantitative methods courses are taught. Using a two‐group pretest–posttest design, we conducted an experiment using an undergraduate social science student sample to investigate whether the introduction of statistical software to teaching quantitative methods would improve knowledge acquisition and attitudes toward quantitative methods courses. Our project confirmed that implementing computer‐assisted instructional methods increased knowledge acquisition in quantitative methods courses compared with students' academic performance in other courses, measured by grade point average. We also found that student attitudes have weak and mostly nonsignificant influence on quantitative methods knowledge tests. Additionally, the paper suggests a curriculum‐level approach to teaching quantitative methods to undergraduate students. 相似文献
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66.
Michael Hudec Kamila Riegerov Jan Pala Viera Kútna Marie ern Valerie Bríd OLeary 《International journal of molecular sciences》2021,22(18)
The autoimmune condition, Celiac Disease (CeD), displays broad clinical symptoms due to gluten exposure. Its genetic association with DQ variants in the human leukocyte antigen (HLA) system has been recognised. Monocyte-derived mature dendritic cells (MoDCs) present gluten peptides through HLA-DQ and co-stimulatory molecules to T lymphocytes, eliciting a cytokine-rich microenvironment. Having access to CeD associated families prevalent in the Czech Republic, this study utilised an in vitro model to investigate their differential monocyte profile. The higher monocyte yields isolated from PBMCs of CeD patients versus control individuals also reflected the greater proportion of dendritic cells derived from these sources following lipopolysaccharide (LPS)/ peptic-tryptic-gliadin (PTG) fragment stimulation. Cell surface markers of CeD monocytes and MoDCs were subsequently profiled. This foremost study identified a novel bio-profile characterised by elevated CD64 and reduced CD33 levels, unique to CD14++ monocytes of CeD patients. Normalisation to LPS stimulation revealed the increased sensitivity of CeD-MoDCs to PTG, as shown by CD86 and HLA-DQ flow cytometric readouts. Enhanced CD86 and HLA-DQ expression in CeD-MoDCs were revealed by confocal microscopy. Analysis highlighted their dominance at the CeD-MoDC membrane in comparison to controls, reflective of superior antigen presentation ability. In conclusion, this investigative study deciphered the monocytes and MoDCs of CeD patients with the identification of a novel bio-profile marker of potential diagnostic value for clinical interpretation. Herein, the characterisation of CD86 and HLA-DQ as activators to stimulants, along with robust membrane assembly reflective of efficient antigen presentation, offers CeD targeted therapeutic avenues worth further exploration. 相似文献
67.
Mehdi Amouei Torkmahalleh Zhuldyz Zhigulina Tomiris Madiyarova Kamila Turganova Enoch K. Adotey Sergei Sabanov 《Indoor air》2021,31(4):1178-1186
Children in preschools were studied as an exceptionally vulnerable group to lung diseases due to their immature immune system. Few data are available in the literature addressing the exposure of children in preschools to ultrafine (>10 nm) particles. Exposure of children to fine, ultrafine (10 nm–1 µm) particles and black carbon particles present inside and near two preschools in Nur-Sultan, Kazakhstan, during Fall 2019 was investigated. For Preschool I, the average daily (6 h) indoor (outdoor) PM1, PM2.5, and PM10 concentrations over three-week measurements were 15.0 (SD 12.5) µg/m3, 34.6 (SD 35.1) µg/m3, and 47.2 (SD 45.2) µg/m3, respectively. Average indoor UFP concentrations (>10.0 nm) including candle burning events were 5.20 × 103 (SD 8.80 × 103) particles/cm3, with the background UFP concentration to be 3.30 × 103 (SD 1.80 × 103) particles/cm3. In Preschool II, the average UFP concentration (>30.0 nm) in the morning and afternoon was 3.94 × 103 (SD 5.34 × 102) and 3.36 × 103 (SD 1.90 × 103) particles/cm3, respectively. Indoor black carbon (BC) concentrations were correlated with the outdoor smoking activity. The major sources of the indoor particles in the preschools were dust resuspension, candle burning, and infiltrated outdoor particles. 相似文献
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Effects of chemical agents on physical properties and structure of primary pulp chamber dentin 下载免费PDF全文
Fernanda Miori Pascon Kamila Rosamilia Kantovitz Juliana Franciele Gaspar Andreia Bolzan De Paula Regina Maria Puppin‐Rontani 《Microscopy research and technique》2014,77(1):52-56
This study evaluated the effects of chemical agents on the physical properties and structure of primary pulp chamber dentin using surface roughness, microhardness tests, and scanning electron microscopy (SEM). Twenty‐five primary teeth were sectioned exposing the pulp chamber and were divided into five groups (n = 5): NT, no treatment; SH1, 1% sodium hypochlorite (NaOCl); SH1U, 1% NaOCl + Endo‐PTC®; SH1E, 1% NaOCl + 17% EDTA; and E, 17% EDTA. After dentin treatment, the specimens were submitted to roughness, microhardness testing, and SEM analysis. Roughness and microhardness data were submitted to one‐way ANOVA and Tukey's test (P < 0.05). The SH1E group showed the highest roughness, followed by the E group (P < 0.05) when compared with the NT, SH1, and SH1U groups. Microhardness values of SH1 and SH1U showed no significant difference as compared to the NT (control) group (P > 0.05). Microhardness values could not be obtained in the EDTA groups (SH1E and E). The presence of intertubular dentin with opened dentin tubules was observed in the NT, SH1, and SH1U groups. SH1E showed eroded and disorganized dentin with few opened tubules and the intertubular/peritubular dentin was partially removed. Considering the physical and structural approaches and the chemical agents studied, it can be concluded that NaOCl and NaOCl associated with Endo‐PTC® were the agents that promoted the smallest changes in surface roughness, microhardness, and structure of the pulp chamber dentin of primary teeth. Microsc. Res. Tech. 77:52–56, 2014. © 2013 Wiley Periodicals, Inc. 相似文献