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排序方式: 共有462条查询结果,搜索用时 234 毫秒
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Fernando J Beltrn F Javier Rivas Olga Gimeno 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(9):973-984
Photocatalytic ozonation (1O3 + VUV + TiO2), ozonation (O3), catalytic ozonation (O3 + TiO2), ozone photolysis (O3 + VUV), photocatalysis (TiO2 + VUV) and photolysis (VUV) have been compared in terms of formation of intermediates, extent of, mineralization (TOC, COD, chloride, nitrate) and kinetics in the aqueous treatment of three phenols (phenol, p‐chlorophenol and p‐nitrophenol). In all cases, photocatalytic ozonation led to lower degradation times for chemical oxygen demand and total organic carbon removal. Intermediates formed were similar in the different oxidation systems with some exceptions. They can be classified into three different types: polyphenols (resorcinol, catechol, hydroquinone), unsaturated carboxylic acids (maleic and fumaric acids) and saturated carboxylic acids (glyoxylic, formic and oxalic acids). First order kinetic equations have been checked for the oxidation processes studied in the case of the parent compound. Rate constants of these systems have also been calculated. Copyright © 2005 Society of Chemical Industry 相似文献
3.
Noemi Eiro Sandra Cid Nuria Aguado María Fraile Nagore de Pablo Berta Fernndez Francisco Domínguez Luis O. Gonzlez Francisco J. Vizoso 《International journal of molecular sciences》2021,22(1)
Tumor-infiltrating immune cells phenotype is associated with tumor progression. However, little is known about the phenotype of the peripheral blood mononuclear cells (PBMC) from breast cancer patients. We investigated MMP1 and MMP11 expression in PBMC from breast cancer patients and we analyzed gene expression changes upon their interaction with cancer cells and cancer-associated fibroblasts (CAF). We measured the impact of PBMC on proinflammatory gene expression in breast cancer cells, normal fibroblast (NF), and CAF and the impact on proliferation and invasiveness capacity of breast cancer cells. Gene expression of MMP1 and MMP11 in PBMC from breast cancer patients (n = 54) and control (n = 28); expression of IL1A, IL6, IL17, IFNβ, and NFĸB in breast cancer cell lines (MCF-7 and MDA-MB-231); and, additionally, IL10 and MMP11 in CAF and NF were analyzed by qRT-PCR before and after co-culture. Our results show the existence of a subpopulation of breast cancer patients (25.9%) with very high levels of MMP11 gene expression in PBMC. Also, gene expression of MMP1 and MMP11 increases in PBMC after co-culture with breast cancer cell lines, NF or CAF. PBMC from healthy or breast cancer patients induce an increased proliferation rate on MCF-7 and an increased invasiveness capacity of MDA-MB-231. Finally, we show a differential expression profile of inflammatory genes in NF and CAF when co-cultured with control or breast cancer PBMC. We have observed that MMPs’ expression in PBMC is regulated by the microenvironment, while the expression of inflammatory genes in NF or CAF is differentially regulated by PBMC. These findings confirm the importance of the crosstalk between stromal cells and suggest that PBMC would play a role in promoting aggressive tumor behavior. 相似文献
4.
Silvia Saturio Alicja M. Nogacka Marta Surez Nuria Fernndez Laura Mantecn Leonardo Mancabelli Christian Milani Marco Ventura Clara G. de los Reyes-Gaviln Gonzalo Solís Silvia Arboleya Miguel Gueimonde 《International journal of molecular sciences》2021,22(7)
The establishment of the gut microbiota poses implications for short and long-term health. Bifidobacterium is an important taxon in early life, being one of the most abundant genera in the infant intestinal microbiota and carrying out key functions for maintaining host-homeostasis. Recent metagenomic studies have shown that different factors, such as gestational age, delivery mode, or feeding habits, affect the gut microbiota establishment at high phylogenetic levels. However, their impact on the specific bifidobacterial populations is not yet well understood. Here we studied the impact of these factors on the different Bifidobacterium species and subspecies at both the quantitative and qualitative levels. Fecal samples were taken from 85 neonates at 2, 10, 30, 90 days of life, and the relative proportions of the different bifidobacterial populations were assessed by 16S rRNA–23S rRNA internal transcribed spacer (ITS) region sequencing. Absolute levels of the main species were determined by q-PCR. Our results showed that the bifidobacterial population establishment is affected by gestational age, delivery mode, and infant feeding, as it is evidenced by qualitative and quantitative changes. These data underline the need for understanding the impact of perinatal factors on the gut microbiota also at low taxonomic levels, especially in the case of relevant microbial populations such as Bifidobacterium. The data obtained provide indications for the selection of the species best suited for the development of bifidobacteria-based products for different groups of neonates and will help to develop rational strategies for favoring a healthy early microbiota development when this process is challenged. 相似文献
5.
María A. Vasco-Mogorrn Jos A. Campillo Adela Periago Valentin Cabaas Mercedes Berenguer María C. García-Garay Lourdes Gimeno María F. Soto-Ramírez María D. Martínez-Hernndez Manuel Muro Alfredo Minguela 《International journal of molecular sciences》2021,22(8)
Proliferation and apoptosis of neoplastic cells are prognostic biomarkers in plasma cell neoplasms (PCNs). The prognostic capacity of proliferation to apoptosis ratio (Ratio-PA) in the era of immunomodulatory treatments is re-evaluated in 316 gammopathy of undetermined significance (MGUS), 57 smoldering multiple myeloma (SMM), and 266 multiple myeloma (MM) patients. Ratio-PA of 0.77 ± 0.12, 1.94 ± 0.52, and 11.2 ± 0.7 (p < 0.0001) were observed in MGUS, SMM, and MM patients. Ten-year overall survival (10y-OS) rates for patients with low/high Ratio-PA were 93.5%/77.3% p < 0.0001) for MGUS, 82.5%/64.7% (p < 0.05) for SMM, and 62.3%/47.0% (p < 0.05) for MM. For patients with low, intermediate, and high risk, 10y-OS for low/high Ratio-PA were 95.5%/72.9% (p < 0.0001), 74.2%/50.4% (p < 0.0001), and 35.3%/20.0% (p = 0.836), respectively. Ratio-PA was an independent prognostic factor for OS (HR = 2.119, p < 0.0001, Harrell-C-statistic = 0.7440 ± 0.0194) when co-analyzed with sex, age, and standard risk. In patients with Ratio-PAhigh, only first-line therapy with VRd/VTd, but not PAD/VCD, coupled with ASCT was associated with high 10y-OS (82.7%). Tumor cell Ratio-PA estimated at diagnosis offers a prognostic biomarker that complements standard risk stratification and helps to guide the clinical management of pre-malignant and symptomatic PCNs. Every effort should be made to provide first-line therapies including VTd or VRd associated with ASCT to patients with Ratio-PAhigh at higher risk of progression and death. 相似文献
6.
Tomasz Z. Tomkiewicz Nuria Surez-Herrera Frans P. M. Cremers Rob W. J. Collin Alejandro Garanto 《International journal of molecular sciences》2021,22(9)
The discovery of novel intronic variants in the ABCA4 locus has contributed significantly to solving the missing heritability in Stargardt disease (STGD1). The increasing number of variants affecting pre-mRNA splicing makes ABCA4 a suitable candidate for antisense oligonucleotide (AON)-based splicing modulation therapies. In this study, AON-based splicing modulation was assessed for 15 recently described intronic variants (three near-exon and 12 deep-intronic variants). In total, 26 AONs were designed and tested in vitro using a midigene-based splice system. Overall, partial or complete splicing correction was observed for two variants causing exon elongation and all variants causing pseudoexon inclusion. Together, our results confirm the high potential of AONs for the development of future RNA therapies to correct splicing defects causing STGD1. 相似文献
7.
Alfredo Jurez-Saldivar Elizabeth Barbosa-Cabrera Edgar E. Lara-Ramírez Alma D. Paz-Gonzlez Ana V. Martínez-Vzquez Virgilio Bocanegra-García Isidro Palos Nuria E. Campillo Gildardo Rivera 《International journal of molecular sciences》2021,22(11)
Infectious diseases caused by intestinal protozoan, such as Entamoeba histolytica (E. histolytica) and Giardia lamblia (G. lamblia) are a worldwide public health issue. They affect more than 70 million people every year. They colonize intestines causing primarily diarrhea; nevertheless, these infections can lead to more serious complications. The treatment of choice, metronidazole, is in doubt due to adverse effects and resistance. Therefore, there is a need for new compounds against these parasites. In this work, a structure-based virtual screening of FDA-approved drugs was performed to identify compounds with antiprotozoal activity. The glycolytic enzyme triosephosphate isomerase, present in both E. histolytica and G. lamblia, was used as the drug target. The compounds with the best average docking score on both structures were selected for the in vitro evaluation. Three compounds, chlorhexidine, tolcapone, and imatinib, were capable of inhibit growth on G. lamblia trophozoites (0.05–4.935 μg/mL), while folic acid showed activity against E. histolytica (0.186 μg/mL) and G. lamblia (5.342 μg/mL). 相似文献
8.
During the last two decades there has been a thorough research and development of standards and protocols in order to cope with different electrocardiogram formats from heterogeneous acquisition systems. Despite the efforts of public and private consortiums on creating a standardized electrocardiogram (ECG) storage format, there is still not a single one. Indeed, there is also the necessity of access to raw data of the ECGs previously acquired. Most of these documents have been saved as Adobe PDF files, since for medical staff it is an easy format for later visualization. However, this format presents difficulties when trying to access original raw data for subsequent studies and signal analysis. In this manner, this paper presents an application that obtains plain numerical data from ECG files stored with PDF format. Data can also be exported to one of the most common file formats in existence, to be easily accessed thereafter. 相似文献
9.
Silphinene Sesquiterpenes as Model Insect Antifeedants 总被引:3,自引:0,他引:3
González-Coloma A Valencia F Martín N Hoffmann JJ Hutter L Marco JA Reina M 《Journal of chemical ecology》2002,28(1):117-129
Silphinene sesquiterpenes are established chrysomelid antifeedants. In this work, nine silphinene analogs, 11-acetoxy-5-angeloyloxysilphinen-3-one (1), 11-acetoxy-5-tigloyloxysilphinen-3-one (2), 11-acetoxy-5-iso- butyryloxysilphinen-3-one (3), 11-hydroxy-5-angeloyloxysilphinen-3-one (4), 11,5-dihydroxysilphinen-3-one (5), 11,5-diacetoxysilphinen-3-one (6), 5,11-diisobutyryloxysilphinen-3-one (7), silphinen-3,5,11-trione (8), and O-methyl-5-epicantabrenolic acid methyl ester (10), and a presilphiperfolane sesquiterpene (9) were tested against several divergent insect species, including the lepidopteran Spodoptera littoralis, the chrysomelid Leptinotarsa decemlineata, and five aphid species, and their antifeedant effects were compared with those of picrotoxinin, a GABA-antagonist, and thymol, an allosteric modulator for insect GABA receptors. All insects tested responded to at least one silphinene analog and/or GABA antagonist. Compound 3 and thymol were effective antifeedants against all species tested except S. littoralis, with varying potencies according to their feeding ecologies. The toxicity of these compounds was species-dependent and did not correlate with their antifeedant effect. 相似文献
10.
The homogeneous decomposition of ozone in the presence of a Co(II) catalyst has been investigated in aqueous solution. Under the conditions investigated (Co(II) concentration: 0.0 – 2.0?ppm, pH: 1.6- 8.4, O3 concentration: 5 10?5 – 2.0 104?M) the process can be assumed to follow pseudo first order kinetics with respect to ozone. Cobalt concentration dependency also obeys first order kinetics although it may be considered to reach a steady state concentration. pH exerts a positive influence on the decomposition rate from 1.6 to 7.1, the process leveling off at pH 8.4. An Arrhenius analysis of the temperature effect gave a moderate activation energy of the global reaction (E=10917?cal mol?1). A more detailed radical mechanism than a simple pseudo first order reaction can be postulated for simulation purposes. By numerical optimization of some unknown kinetic constants the influence of several operating variables can be adequately predicted. 相似文献