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排序方式: 共有118条查询结果,搜索用时 46 毫秒
81.
Matthieu Pérard Justine Le Clerc Fleur Meary Fabienne Pérez Sylvie Tricot-Doleux Pascal Pellen-Mussi 《Journal of materials science. Materials in medicine》2013,24(6):1527-1534
The primary objective of this study was to assess the biological effects of a new dentine substitute based on Ca3SiO5 (Biodentine?) for use in pulp-capping treatment, on pseudo-odontoblastic (MDPC-23) and pulp (Od-21) cells. The secondary objective was to evaluate the effects of Biodentine and mineral trioxide aggregate (MTA) on gene expression in cultured spheroids. We used the acid phosphatase assay to compare the biocompatibility of Biodentine and MTA. Cell differentiation was investigated by RT-qPCR. We investigated the expression of genes involved in odontogenic differentiation (Runx2), matrix secretion (Col1a1, Spp1) and mineralisation (Alp). ANOVA and PLSD tests were used for data analysis. MDPC-23 cells cultured in the presence of MTA had higher levels of viability than those cultured in the presence of Biodentine and control cells on day 7 (P = 0.0065 and P = 0.0126, respectively). For Od-21 cells, proliferation rates on day 7 were significantly lower in the presence of Biodentine or MTA than for control (P < 0.0001). Col1a1 expression levels were slightly lower in cells cultured in the presence of MTA than in those cultured in the presence of Biodentine and in control cells. Biodentine and MTA may modify the proliferation of pulp cell lines. Their effects may fluctuate over time, depending on the cell line considered. The observed similarity between Biodentine and MTA validates the indication for direct pulp-capping claimed by the manufacturers. 相似文献
82.
Andrew P. Breksa III Gary R. Takeoka Marlene B. Hidalgo Ana Vilches Justine Vasse David W. Ramming 《Food chemistry》2010
Six raisin grape cultivars and 10 new raisin grape selections were analyzed for antioxidant activity (ABTS assay) and for total and individual phenolic compounds. Samples were freeze–dried and values are reported on a dry weight basis. Antioxidant activity across the 16 samples ranged from 7.7 to 60.9 μmol Trolox/g DW, with A95-27 exhibiting the greatest activity. Total phenolic content, determined in gallic acid equivalents using the Folin–Ciocalteau assay, ranged from 316.3 to 1141.3 mg gallic acid/100 g DW and was strongly correlated (r = 0.990) with antioxidant results. Concentrations of individual phenolics were determined by HPLC. trans-Caftaric acid was the predominant compound in all samples. A95-15 contained the lowest concentration (153.5 μg/g DW) of caftaric acid, while Fiesta contained the highest concentration (598.7 μg/g DW). Selections A56-66, A95-15, and A95-27 had much higher levels of catechin (86.5–209.1 μg/g DW) and epicatechin (126.5–365.7 μg/g DW) than the other samples. 相似文献
83.
First report of methicillin‐resistant Staphylococcus aureus in tank cultured dusky kob (Argyrosomus japonicus), and evaluation of three phenotypic methods in the detection of MRSA 下载免费PDF全文
This study was conducted to ascertain the occurrence of methicillin‐resistant Staphylococcus aureus (MRSA) in marine finfish (Argyrosomus japonicus) harvested from the wild and two re‐circulatory aquaculture systems, and evaluating the reliability of three phenotypic methods in the detection of methicillin resistance. A total of 120 dusky kob fish were sampled for S. aureus detection using conventional methods and confirmed by polymerase chain reaction (PCR) targeting the nuc gene. Methicillin resistance was determined by molecular detection of the mecA gene. Using mecA as the defining standard, the specificities and sensitivities of cefoxitin disc diffusion, oxacillin screen agar, and growth of S. aureus on Brilliance MRSA II Agar were evaluated. A total of 321 presumptive S. aureus isolates were recovered by culture, out of which 202 (62.9%) were confirmed by PCR. Of these, 33 (16.3%) strains were mecA positive while 169 (83.7%) were mecA negative. The sensitivities and specificities of MRSA detection was 93.9 and 91.7%, 81.8 and 92.3%, and 87.9 and 94.1% for cefoxitin disc, oxacillin screen agar test, and Brilliance MRSA II agar, respectively. This is so far the first report of MRSA in dusky kob aquaculture in South Africa. In the absence of molecular techniques, cefoxitin disc diffusion test is recommended along with any other phenotypic method to improve MRSA detection from samples of veterinary origin.
Practical implications
Methicillin‐resistant Staphylococcus aureus currently presents one of the greatest challenges for medical research worldwide, as well as is one of the most important causes of bacteria gastroenteritis due to preformed toxins in foods. There is a dearth of knowledge on marine foods as carriers/sources of MRSA infection. There are also major discrepancies obtained with MRSA detection methods, making effective detection of this pathogen complicated. The results from this study show that healthy aquaculture fish are reservoirs of MRSA, thus it is necessary to regularly monitor marine foods. Cefoxitin disc diffusion test is recommended as the preferred method for detection of MRSA from fish/food samples where molecular methods are lacking. 相似文献84.
Shults RA Elder RW Sleet DA Thompson RS Nichols JL 《Accident; analysis and prevention》2004,36(3):491-493
A recent systematic literature review found that primary enforcement laws are more effective at increasing seat belt use than secondary laws in the United States. This report re-examines the studies included in the systematic review to explore whether the benefits of a primary law differ based on: (1) the baseline seat belt use rate; or (2) whether or not the primary law replaces a secondary law. States that directly enacted primary laws showed larger increases in observed seat belt use (median increase of 33 percentage points). These laws were enacted in the mid-1980s, when baseline belt use rates were below 35%. Smaller, but substantial increases in belt use were observed in states that replaced secondary with primary laws (median increase of 14 percentage points). Baseline belt use rates in these states ranged from 47 to 73%. Primary safety belt laws can further increase seat belt use even in states with relatively high baseline levels of belt use. 相似文献
85.
Shults M.C. Rhodes R.K. Updike S.J. Gilligan B.J. Reining W.N. 《IEEE transactions on bio-medical engineering》1994,41(10):937-942
An implantable potentiostat-radiotelemetry system for in vivo sensing of glucose is described. An enzyme electrode sensor measures the oxidation current of hydrogen peroxide formed by the stoichiometric conversion of glucose substrate and oxygen cofactor in an immobilized glucose oxidase layer. The sensor current is converted to a frequency and transmitted at programmable intervals (4, 32, 256 s) to a remote receiver. Low power CMOS circuitry is employed and device operation for up to 1.5 years is predicted using two series connected 250 mAh lithium cells. Crystal controlled RF frequencies uniquely identify each sensor allowing over 10 sensors within the same 10 m radius. A custom interface card allows a PC to program the receiver and handle the transmitted sensor data using software written in Microsoft C and QuickBasic. Software control allows on-the-fly sensor addition or subtraction to the sensor group being monitored. Over 10 sensors can be tracked long-term using the longest transmit interval, or four sensors can be tracked during short-term infusion studies when the transmit interval is reduced to 4 s. The design, construction, operation, and performance of the system hardware and software are described and evaluated 相似文献
86.
87.
Peshkichev I. V. Bochkareva A. A. Kuropatenko V. F. Makeyeva I. R. Shults O. V. 《Radiochemistry》2019,61(5):535-540
Radiochemistry - Thermodynamic modeling was performed to study and evaluate the behavior of the physicochemical system characteristic of the carbothermal synthesis of uranium and plutonium... 相似文献
88.
Amide hydrogen/deuterium (H/D) exchange coupled with mass spectrometry has become a powerful tool to study protein dynamics. Addition of a proteolysis step between the exchange reaction and mass analysis can be used to localize the positions of deuterium and improve overall resolution. The resolution can be further enhanced by the fragmentation of digested peptides in the gas phase if scrambling of exchangeable hydrogens and deuteriums on the peptides does not occur. Although some laboratories reported successful localization of deuteriums by gas-phase fragmentations, others described total scrambling. Here we propose a simple method to detect the presence or absence of scrambling using a commercially available small peptide, neurotensin (9-13; RPYIL). All exchangeable hydrogens on this pentapeptide are first deuterated by dissolving it in deuterium oxide. The deuterated peptide is loaded onto a reversed-phase column, and then washed with copious amounts of cold acidic aqueous buffer. This washing exchanges all deuteriums on both the terminals and the side chains back to hydrogens. Now only three deuteriums are attached on the pentapeptide, one on each of the amide nitrogens of Y, I, and L. After the partially deuterated peptide is eluted from the column with 95% acidic acetonitrile, collision-induced dissociation (CID) generates a series of b ions, which are analyzed by mass spectrometer. In the absence of scrambling, no deuterium should be observed in the b 2 ion, as neither R nor P have amide hydrogens. On the other hand, in the event of scrambling, b 2 should carry about half of the deuteriums of the parent pentapeptide. In theory, complete scrambling should distribute deuteriums equally among all of the exchangeable hydrogens. The b 2 portion of neurotensin (9-13) has 6 exchangeable hydrogens, whereas the +1 charge state of neurotensin (9-13) has 12 exchangeable hydrogens. We demonstrated that CID caused complete scrambling of hydrogens and deuteriums with an LCQ (a ion trap machine). 相似文献
89.
Juan Manuel Chao de la Barca Alexis Richard Pauline Robert Maroua Eid Olivier Fouquet Lydie Tessier Cline Wetterwald Justine Faure Celine Fassot Daniel Henrion Pascal Reynier Laurent Loufrani 《International journal of molecular sciences》2022,23(12)
Aneurysm is the second-most common disease affecting the aorta worldwide after atherosclerosis. While several clinical metabolomic studies have been reported, no study has reported deep metabolomic phenotyping in experimental animal models of aortic aneurysm. We performed a targeted metabolomics study on the blood and aortas of an experimental mice model of aortic aneurysm generated by high-cholesterol diet and angiotensin II in Ldlr−/− mice. The mice model showed a significant increase in media/lumen ratio and wall area, which is associated with lipid deposition within the adventitia, describing a hypertrophic remodeling with an aneurysm profile of the abdominal aorta. Altered aortas showed increased collagen remodeling, disruption of lipid metabolism, decreased glucose, nitric oxide and lysine metabolisms, and increased polyamines and asymmetric dimethylarginine (ADMA) production. In blood, a major hyperlipidemia was observed with decreased concentrations of glutamine, glycine, taurine, and carnitine, and increased concentrations of the branched amino acids (BCAA). The BCAA/glycine and BCAA/glutamine ratios discriminated with very good sensitivity and specificity between aneurysmatic and non-aneurysmatic mice. To conclude, our results reveal that experimental induction of aortic aneurysms causes a profound alteration in the metabolic profile in aortas and blood, mainly centered on an alteration of NO, lipid, and energetic metabolisms. 相似文献
90.
Leslie Marisol Lugo-Gavidia Janis M. Nolde Revathy Carnagarin Dylan Burger Justine Chan Sandi Robinson Erika Bosio Vance B. Matthews Markus P. Schlaich 《International journal of molecular sciences》2022,23(18)
Elevated circulating platelet-derived extracellular vesicles (EVs) have been reported in conditions associated with thrombotic risk. The present study aimed to assess the relationship between circulating platelet-derived EV levels, cardiovascular risk stratification and vascular organ damage, as assessed by pulse wave velocity (PWV). A total of 92 patients were included in the present analysis. Platelet EV were evaluated by flow cytometry (CD41+/Annexin v+). The cardiovascular risk was determined using the 2021 ESC guideline stratification and SCORE2 and SCORE-OP. PWV was performed as a surrogate to assess macrovascular damage. Risk stratification revealed significant group differences in EV levels (ANOVA, p = 0.04). Post hoc analysis demonstrated significantly higher levels of EVs in the very high-risk group compared with the young participants (12.53 ± 8.69 vs. 7.51 ± 4.67 EV/µL, p = 0.03). Linear regression models showed SCORE2 and SCORE-OP (p = 0.04) was a predictor of EV levels. EVs showed a significant association with macrovascular organ damage measured by PWV (p = 0.01). PWV progressively increased with more severe cardiovascular risk (p < 0.001) and was also associated with SCORE2 and SCORE-OP (p < 0.001). Within the pooled group of subjects with low to moderate risk and young participants (<40 years), those with EV levels in the highest tertile had a trend towards higher nocturnal blood pressure levels, fasting glucose concentration, lipid levels, homocysteine and PWV. Levels of platelet-derived EVs were highest in those patients with very high CV risk. Within a pooled group of patients with low to moderate risk, an unfavourable cardiometabolic profile was present with higher EV levels. 相似文献