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排序方式: 共有1235条查询结果,搜索用时 15 毫秒
181.
Anna Barile Philippa Mills Martino L. di Salvo Claudio Graziani Victoria Bunik Peter Clayton Roberto Contestabile Angela Tramonti 《International journal of molecular sciences》2021,22(21)
Several variants of the enzyme pyridox(am)ine 5′-phosphate oxidase (PNPO), responsible for a rare form of vitamin B6-dependent neonatal epileptic encephalopathy known as PNPO deficiency (PNPOD), have been reported. However, only a few of them have been characterised with respect to their structural and functional properties, despite the fact that the knowledge of how variants affect the enzyme may clarify the disease mechanism and improve treatment. Here, we report the characterisation of the catalytic, allosteric and structural properties of recombinantly expressed D33V, R161C, P213S, and E50K variants, among which D33V (present in approximately 10% of affected patients) is one of the more common variants responsible for PNPOD. The D33V and E50K variants have only mildly altered catalytic properties. In particular, the E50K variant, given that it has been found on the same chromosome with other known pathogenic variants, may be considered non-pathogenic. The P213S variant has lower thermal stability and reduced capability to bind the FMN cofactor. The variant involving Arg161 (R161C) largely decreases the affinity for the pyridoxine 5′-phosphate substrate and completely abolishes the allosteric feedback inhibition exerted by the pyridoxal 5′-phosphate product. 相似文献
182.
Andrs Rincn-Riveros Duvan Morales Josefa Antonia Rodríguez Victoria E. Villegas Liliana Lpez-Kleine 《International journal of molecular sciences》2021,22(21)
Noncoding RNAs (ncRNAs) play prominent roles in the regulation of gene expression via their interactions with other biological molecules such as proteins and nucleic acids. Although much of our knowledge about how these ncRNAs operate in different biological processes has been obtained from experimental findings, computational biology can also clearly substantially boost this knowledge by suggesting possible novel interactions of these ncRNAs with other molecules. Computational predictions are thus used as an alternative source of new insights through a process of mutual enrichment because the information obtained through experiments continuously feeds through into computational methods. The results of these predictions in turn shed light on possible interactions that are subsequently validated experimentally. This review describes the latest advances in databases, bioinformatic tools, and new in silico strategies that allow the establishment or prediction of biological interactions of ncRNAs, particularly miRNAs and lncRNAs. The ncRNA species described in this work have a special emphasis on those found in humans, but information on ncRNA of other species is also included. 相似文献
183.
184.
Jiangtian Xu Victoria L. Dimonie E. David Sudol Olga L. Shaffer Mohamed S. El-Aasser 《应用聚合物科学杂志》1998,69(5):977-984
The mechanism of film formation and crosslinking in a poly(methyl methacrylate/n-butyl acrylate/TMI®) (PMBT) and amino-telechelic polybutadiene (PBD-NH2) latex blend was studied. Films cast from the latex blends were ultramicrotomed and examined by transmission electron microscopy. The PBD-NH2 was found to be located primarily at the surface of the PMBT particles due to a crosslinking reaction. Without the possibility of crosslinking (when TMI was absent in the acrylic copolymer), the PBD-NH2 only formed segregated phases in the acrylic polymer matrix due to the incompatibility of the two polymers. While this PBD-NH2 could be extracted with toluene, the PBD-NH2 crosslinked at the PMBT particle surfaces was not extractable. FTIR results showed that the isocyanate groups in the PMBT were completely consumed when the PBD-NH2 concentration was sufficiently high, indicating that the PBD-NH2 had diffused and reacted inside the PMBT particles. Thus, the crosslinking reaction was considered to be the driving force for the diffusion of the PBD-NH2 into the PMBT particles. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 977–984, 1998 相似文献
185.
Natalia A. Shnayder Victoria B. Sharavii Marina M. Petrova Polina V. Moskaleva Elena A. Pozhilenkova Darya S. Kaskaeva Olga. V. Tutynina Tatiana E. Popova Natalia P. Garganeeva Regina F. Nasyrova 《International journal of molecular sciences》2021,22(16)
Chronic headache is a topical problem of neurology, psychiatry and general practice. The medication-overuse headache (MOH) is one of the leading pathologies in the structure of chronic headache. However, early diagnosis of the MOH is challenging. We analyzed potential proteomic biomarkers of serum and urine in patients with MOH. Methods: We searched PubMed, Springer, Scopus, Web of Science, ClinicalKey, and Google Scholar databases for English publications over the past 10 years using keywords and their combinations. Results: We found and analyzed seven studies that met the search criteria for the purpose of the review, including 24 serum proteomic biomarkers and 25 urine proteomic biomarkers of MOH. Moreover, the candidate genes and locus of the studied serum (vitamin D-binding protein, lipocalin-type prostaglandin D2 synthase, apolipoprotein E, etc.) and urine proteomic biomarkers (uromodulin, alpha-1-microglobulin, zinc-alpha-2-glycoprotein, etc.) of MOH are presented in this review. Conclusions: The serum and urine proteomic biomarkers of MOH can potentially help with the identification of patients with MOH development. Due to the relevance of the problem, the authors believe that further investigation of the MOH proteomic biomarkers in different ethnic and racial groups of patients with primary headache is necessary. In addition, it is important to investigate whether medications of different drug classes influence the levels of serum and urine proteomic biomarkers. 相似文献
186.
María José García José Luis Aleixandre Inmaculada Álvarez Victoria Lizama 《European Food Research and Technology》2009,229(1):133-139
Fining agents can also have an effect on the flavor components of the must, and other compounds which are important for the
sensory characteristics and in the case of sparkling wine, the foam quality. The influence of fining agents and tirage solution,
on volatile compounds, and foam characteristics of sparkling wines made from grapes of the Bobal variety was studied. The
data obtained show how the fining agent affects the foam properties and the final volatile composition of sparkling wines.
In this study, it was bentonite with gelatine that produced amounts of acetates and esters. The use of Colle 2P in the tirage
solution means that more aromatic sparkling wines with better foam characteristics can be obtained. 相似文献
187.
Antonio López-López Francisco Rodríguez-GómezM. Victoria Ruíz-Méndez Amparo Cortés-DelgadoAntonio Garrido-Fernández 《Food chemistry》2009
The aim of the work was to study the effects of processing on the unsaponifiable matter, sterols and fatty and triterpenic alcohol in ripe olive fat (Manzanilla and Hojiblanca cultivars) and to disclose the most influential factors using GLM, PCA and DA. There were significant effects of cultivars or ps on unsaponifiable matter, β-sitosterol, Δ5-avenasterol, total sterols, 1-docosanol, 1-tetracosanol (ps), erythrodiol and percentage erythrodiol + uvaol. The values of most of these parameters were within the limits established by the EU Directives for olive and pomace oils but classification of the respective oils was not conclusive. Predictive discriminant analysis using these variables permitted 100% success in the classification according to cultivars and ps (68% in the case of cross validation). Results revealed that some influential steps should be re-designed, particularly the storage phase, in order to minimise changes in the studied fat components during ripe olive processing. 相似文献
188.
Food composition tables have become important tools to estimate and monitor the nutritional composition of foods next to chemical analysis. However, as analytical methods, calculation methods and obtained results differ significantly within various sources of food composition information. Because calculation methods and obtained results differ significantly within various sources of food composition information, it is indeed a challenge to build, harmonise and compile a food composition database from scattered resources and hard copy tables. This situation has been challenged and addressed in Spain with the support of EuroFIR and governmental bodies (Spanish Food Safety and Nutrition Authority, AESAN), and the Spanish Food Composition Database Network (RedBDECA) has been set up. The proposed aims of the initiative are: to identify and evaluate the main sources of food composition data in Spain; to promote communication within national groups and with EuroFIR; to design and develop a web page for the dissemination of its activities; and to create a consortium to ensure the sustainability of the Spanish Food Composition Database. 相似文献
189.
Samuel Martinez-Erro Francisco Navas Eva Romaní-Cubells Paloma Fernndez-García Victoria Morales Raul Sanz Rafael A. García-Muoz 《International journal of molecular sciences》2021,22(15)
Mesoporous silica nanomaterials have emerged as promising vehicles in controlled drug delivery systems due to their ability to selectively transport, protect, and release pharmaceuticals in a controlled and sustained manner. One drawback of these drug delivery systems is their preparation procedure that usually requires several steps including the removal of the structure-directing agent (surfactant) and the later loading of the drug into the porous structure. Herein, we describe the preparation of mesoporous silica nanoparticles, as drug delivery systems from structure-directing agents based on the kidney-protector drug cilastatin in a simple, fast, and one-step process. The concept of drug-structure-directing agent (DSDA) allows the use of lipidic derivatives of cilastatin to direct the successful formation of mesoporous silica nanoparticles (MSNs). The inherent pharmacological activity of the surfactant DSDA cilastatin-based template permits that the MSNs can be directly employed as drug delivery nanocarriers, without the need of extra steps. MSNs thus synthesized have shown good sphericity and remarkable textural properties. The size of the nanoparticles can be adjusted by simply selecting the stirring speed, time, and aging temperature during the synthesis procedure. Moreover, the release experiments performed on these materials afforded a slow and sustained drug release over several days, which illustrates the MSNs potential utility as drug delivery system for the cilastatin cargo kidney protector. While most nanotechnology strategies focused on combating the different illnesses this methodology emphasizes on reducing the kidney toxicity associated to cancer chemotherapy. 相似文献
190.
Amelia R. Tanner Cameron S. Lynch Victoria C. Kennedy Asghar Ali Quinton A. Winger Paul J. Rozance Russell V. Anthony 《International journal of molecular sciences》2021,22(15)
Deficiency of the placental hormone chorionic somatomammotropin (CSH) can lead to the development of intrauterine growth restriction (IUGR). To gain insight into the physiological consequences of CSH RNA interference (RNAi), the trophectoderm of hatched blastocysts (nine days of gestational age; dGA) was infected with a lentivirus expressing either a scrambled control or CSH-specific shRNA, prior to transfer into synchronized recipient sheep. At 90 dGA, umbilical hemodynamics and fetal measurements were assessed by Doppler ultrasonography. At 120 dGA, pregnancies were fitted with vascular catheters to undergo steady-state metabolic studies with the 3H2O transplacental diffusion technique at 130 dGA. Nutrient uptake rates were determined and tissues were subsequently harvested at necropsy. CSH RNAi reduced (p ≤ 0.05) both fetal and uterine weights as well as umbilical blood flow (mL/min). This ultimately resulted in reduced (p ≤ 0.01) umbilical IGF1 concentrations, as well as reduced umbilical nutrient uptakes (p ≤ 0.05) in CSH RNAi pregnancies. CSH RNAi also reduced (p ≤ 0.05) uterine nutrient uptakes as well as uteroplacental glucose utilization. These data suggest that CSH is necessary to facilitate adequate blood flow for the uptake of oxygen, oxidative substrates, and hormones essential to support fetal and uterine growth. 相似文献