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101.
Ludmila Lukyanova Elita Germanova Natalya Khmil Lybov Pavlik Irina Mikheeva Maria Shigaeva Galina Mironova 《International journal of molecular sciences》2021,22(16)
This study was the first comprehensive investigation of the dependence of mitochondrial enzyme response (catalytic subunits of mitochondrial complexes (MC) I-V, including NDUFV2, SDHA, Cyt b, COX1 and ATP5A) and mitochondrial ultrastructure in the rat cerebral cortex (CC) on the severity and duration of in vivo hypoxic exposures. The role of individual animal’s resistance to hypoxia was also studied. The respiratory chain (RC) was shown to respond to changes in environmental [O2] as follows: (a) differential reaction of mitochondrial enzymes, which depends on the severity of the hypoxic exposure and which indicates changes in the content and catalytic properties of mitochondrial enzymes, both during acute and multiple exposures; and (b) ultrastructural changes in mitochondria, which reflect various degrees of mitochondrial energization. Within a specific range of reduced O2 concentrations, activation of the MC II is a compensatory response supporting the RC electron transport function. In this process, MC I develops new kinetic properties, and its function recovers in hypoxia by reprograming the RC substrate site. Therefore, the mitochondrial RC performs as an in vivo molecular oxygen sensor. Substantial differences between responses of rats with high and low resistance to hypoxia were determined. 相似文献
102.
Businelle Michael S.; Kendzor Darla E.; Reitzel Lorraine R.; Costello Tracy J.; Cofta-Woerpel Ludmila; Li Yisheng; Mazas Carlos A.; Vidrine Jennifer Irvin; Cinciripini Paul M.; Greisinger Anthony J.; Wetter David W. 《Canadian Metallurgical Quarterly》2010,29(3):262
Objective: Although there has been a socioeconomic gradient in smoking prevalence, cessation, and disease burden for decades, these disparities have become even more pronounced over time. The aim of the current study was to develop and test a conceptual model of the mechanisms linking socioeconomic status (SES) to smoking cessation. Design: The conceptual model was evaluated using a latent variable modeling approach in a sample of 424 smokers seeking treatment (34% African American; 33% Latino; 33% White). Hypothesized mechanisms included social support, neighborhood disadvantage, negative affect/stress, agency, and craving. Main Outcome Measure: The primary outcome was Week 4 smoking status. Results: As was hypothesized, SES had significant direct and indirect effects on cessation. Specifically, neighborhood disadvantage, social support, negative affect/stress, and agency mediated the relation between SES and smoking cessation. A multiple group analysis indicated that the model was a good fit across racial/ethnic groups. Conclusion: The present study yielded one of the more comprehensive models illuminating the specific mechanisms that link SES and smoking cessation. Policy, community, and individual-level interventions that target low SES smokers and address the specific pathways identified in the current model could potentially attenuate the impact of SES on cessation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Galina Vladimirovna Kontsevaya Ludmila Alekseevna Gerlinskaya Yury Mikhailovich Moshkin Margarita Vladimirovna Anisimova Aliya Konstantinovna Stanova Tatyana Ivanovna Babochkina Mikhail Pavlovich Moshkin 《International journal of molecular sciences》2021,22(19)
The latest vaccination campaign has actualized the potential impact of antigenic stimuli on reproductive functions. To address this, we mimicked vaccination’s effects by administering keyhole limpet hemocyanin (KLH ) to CD1 male mice and used their sperm for in vitro fertilization (IVF). Two-cell embryos after IVF with spermatozoa from control (C) or KLH-treated (Im) male mice were transferred to surrogate mothers mated with vasectomized control (C) or KLH-treated (Im) male mice, resulting in four experimental groups: C–C, Im–C, C–Im, and Im–Im. The pre-implantation losses were significantly lower in the Im–C group than in the C–Im group. At the same time, the resorption rates reduced markedly in the C–Im compared to the Im–C group. Embryo and placenta weights were significantly higher in the Im–Im group. Although the GM-CSF levels were lower in the amniotic fluid of the gestating surrogate mothers in the Im–Im group, they were strongly correlated with embryo mass. The number–size trade-off was only significant in the Im–Im group. This suggests a positive, cooperative effect of spermatozoa and seminal fluid from immune-primed males on embryo growth and the optimal distribution of surrogate mother maternal resources despite the negative impact of males’ antigenic challenge on the IVF success rate. 相似文献
104.
Zhao Li Sai‐Wing Tsang Xiaomei Du Ludmila Scoles Gilles Robertson Yanguang Zhang Floyd Toll Ye Tao Jianping Lu Jianfu Ding 《Advanced functional materials》2011,21(17):3331-3336
A series of alternating copolymers of cyclopenta[2,1‐b;3,4‐b′]dithiophene (CPDT) and thieno[3,4‐c]pyrrole‐4,6‐dione (TPD) have been prepared and characterized for polymer solar cell (PSC) applications. Different alkyl side chains, including butyl (Bu), hexyl (He), octyl (Oc), and 2‐ethylhexyl (EH), are introduced to the TPD unit in order to adjust the packing of the polymer chain in the solid state, while the hexyl side chain on the CPDT unit remains unchanged to simplify discussion. The polymers in this series have a simple main chain structure and can be synthesized easily, have a narrow band gap and a broad light absorption. The different alkyl chains on the TPD unit not only significantly influence the solubility and chain packing, but also fine tune the energy levels of the polymers. The polymers with Oc or EH group have lower HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energy levels, resulting higher open circuit voltages (Voc) of the PSC devices. Power conversion efficiencies (PCEs) up to 5.5% and 6.4% are obtained from the devices of the Oc substituted polymer (PCPDTTPD‐Oc) with PC61BM and PC71BM, respectively. This side chain effect on the PSC performance is related to the formation of a fine bulk heterojunction structure of polymer and PCBM domains, as observed with atomic force microscopy. 相似文献
105.
Zabka M Pavela R Gabrielova-Slezakova L 《Journal of the science of food and agriculture》2011,91(3):492-497
BACKGROUND: Increasing evidence of fungicide‐resistant toxinogenic and pathogenic fungal species is obvious. Looking for new possibilities of antifungal treatment or sources of antifungal substances is a major problem. Some medicinal plants exert strong antifungal properties and could be conveniently used as a promising alternative source for presently problematic antifungal treatment in many areas with respect to their natural origin. Methanol extracts of 46 medicinal plants from the Eurasian area were used in a screening assay for antifungal activity in this study. The growth inhibitory effect was tested against six significant pathogenic and toxinogenic fungal species: Fusarium oxysporum, F. verticillioides, Penicillium expansum, P. brevicompactum, Aspergillus flavus and A. fumigatus. RESULTS: For 14 plant species, the possibility of using them as natural fungicides was indicated. The extract from Grindelia camporum showed significant activity against all target fungal species. The most sensitive target fungus was the toxinogenic and human pathogenic species A. fumigatus. CONCLUSION: This study has identified 14 extracts of medicinal plants with a potential use as an antifungal treatment in various areas. One of them showed promising efficiency against all selected significant pathogenic and toxinogenic fungal species. Copyright © 2010 Society of Chemical Industry 相似文献
106.
Gabriela Petrisor Ludmila Motelica Luminita Narcisa Craciun Ovidiu Cristian Oprea Denisa Ficai Anton Ficai 《International journal of molecular sciences》2022,23(7)
Melissa officinalis is a medicinal plant rich in biologically active compounds which is used worldwide for its therapeutic effects. Chemical studies on its composition have shown that it contains mainly flavonoids, terpenoids, phenolic acids, tannins, and essential oil. The main active constituents of Melissa officinalis are volatile compounds (geranial, neral, citronellal and geraniol), triterpenes (ursolic acid and oleanolic acid), phenolic acids (rosmarinic acid, caffeic acid and chlorogenic acid), and flavonoids (quercetin, rhamnocitrin, and luteolin). According to the biological studies, the essential oil and extracts of Melissa officinalis have active compounds that determine many pharmacological effects with potential medical uses. A new field of research has led to the development of controlled release systems with active substances from plants. Therefore, the essential oil or extract of Melissa officinalis has become a major target to be incorporated into various controlled release systems which allow a sustained delivery. 相似文献
107.
Vasilisa V. Krasitskaya Alexander N. Kudryavtsev Roman N. Yaroslavtsev Dmitry A. Velikanov Oleg A. Bayukov Yulia V. Gerasimova Sergey V. Stolyar Ludmila A. Frank 《International journal of molecular sciences》2022,23(10)
Starch-coated magnetic iron oxide nanoparticles have been synthesized by a simple, fast, and cost-effective co-precipitation method with cornstarch as a stabilizing agent. The structural and magnetic characteristics of the synthesized material have been studied by transmission electron microscopy, Mössbauer spectroscopy, and vibrating sample magnetometry. The nature of bonds between ferrihydrite nanoparticles and a starch shell has been examined by Fourier transform infrared spectroscopy. The data on the magnetic response of the prepared composite particles have been obtained by magnetic measurements. The determined magnetic characteristics make the synthesized material a good candidate for use in magnetic separation. Starch-coated magnetic iron oxide nanoparticles have been tested as an affinity sorbent for one-step purification of several recombinant proteins (cardiac troponin I, survivin, and melanoma inhibitory activity protein) bearing the maltose-binding protein as an auxiliary fragment. It has been shown that, due to the highly specific binding of this fragment to the starch shell, the target fusion protein is selectively immobilized on magnetic nanoparticles and eluted with the maltose solution. The excellent efficiency of column-free purification, high binding capacity of the sorbent (100–500 µg of a recombinant protein per milligram of starch-coated magnetic iron oxide nanoparticles), and reusability of the obtained material have been demonstrated. 相似文献
108.
Dmitry Rasskazov Irina Chadaeva Ekaterina Sharypova Karina Zolotareva Bato Khandaev Petr Ponomarenko Nikolay Podkolodnyy Natalya Tverdokhleb Oleg Vishnevsky Anton Bogomolov Olga Podkolodnaya Ludmila Savinkova Elena Zemlyanskaya Vadimir Golubyatnikov Nikolay Kolchanov Mikhail Ponomarenko 《International journal of molecular sciences》2022,23(15)
Synthetic targeted optimization of plant promoters is becoming a part of progress in mainstream postgenomic agriculture along with hybridization of cultivated plants with wild congeners, as well as marker-assisted breeding. Therefore, here, for the first time, we compiled all the experimental data—on mutational effects in plant proximal promoters on gene expression—that we could find in PubMed. Some of these datasets cast doubt on both the existence and the uniqueness of the sought solution, which could unequivocally estimate effects of proximal promoter mutation on gene expression when plants are grown under various environmental conditions during their development. This means that the inverse problem under study is ill-posed. Furthermore, we found experimental data on in vitro interchangeability of plant and human TATA-binding proteins allowing the application of Tikhonov’s regularization, making this problem well-posed. Within these frameworks, we created our Web service Plant_SNP_TATA_Z-tester and then determined the limits of its applicability using those data that cast doubt on both the existence and the uniqueness of the sought solution. We confirmed that the effects (of proximal promoter mutations on gene expression) predicted by Plant_SNP_TATA_Z-tester correlate statistically significantly with all the experimental data under study. Lastly, we exemplified an application of Plant_SNP_TATA_Z-tester to agriculturally valuable mutations in plant promoters. 相似文献
109.
Olga Levchenko Elena Dadali Ludmila Bessonova Nina Demina Galina Rudenskaya Galina Matyushchenko Tatiana Markova Inga Anisimova Natalia Semenova Olga Shchagina Oxana Ryzhkova Rena Zinchenko Varvara Galkina Victoria Voinova Sabina Nagieva Alexander Lavrov 《International journal of molecular sciences》2022,23(14)
Intellectual development disorder (IDD) is characterized by a general deficit in intellectual and adaptive functioning. In recent years, there has been a growing interest in studying the genetic structure of IDD. Of particular difficulty are patients with non-specific IDD, for whom it is impossible to establish a clinical diagnosis without complex genetic diagnostics. We examined 198 patients with non-specific IDD from 171 families using whole-exome sequencing and chromosome microarray analysis. Hereditary forms of IDD account for at least 35.7% of non-specific IDD, of which 26.9% are monogenic forms. Variants in the genes associated with the BAF (SWI/SNF) complex were the most frequently identified. We were unable to identify phenotypic features that would allow differential diagnosis of monogenic and microstructural chromosomal rearrangements in non-specific IDD at the stage of clinical examination, but due to its higher efficiency, exome sequencing should be the diagnostic method of the highest priority study after the standard examination of patients with NIDD in Russia. 相似文献
110.
Ludmila A. Vikhristyuk 《国际水资源开发杂志》1996,12(4):547-560
An attempt has been made to ascertain the structure of water masses of the Kuibyshev reservoir, one of the largest in Europe, using mathematical techniques and results of long-term observations (1958-84) of the hydrochemical regime (a gaseous regime, biogenic and organic substances) in the reservoir. The principal features of the structure obtained appeared to be its well-defined two-vector pattern describing two directions of changing water masses along the former bed of the Volga river, as well as the stability of this system in time. Regionalization of the reservoir's water area has yielded five zones differing in water quality. The long-term observationshave enabled the establishment of a certain trend in biogenic concentrations showing their increase since the end of the 1970s and continuing at the present time. This is believed to result primarily from increasing water volume in the Volga river and accelerating anthropogenic pressure upon the reservoir. 相似文献