排序方式: 共有128条查询结果,搜索用时 255 毫秒
61.
Kucharova K Lukacova N Pavel J Radonak J Hefferan MP Kolesar D Kolesarova M Marsala M Marsala J 《Cellular and molecular neurobiology》2006,26(7-8):1293-1308
1. Brief interruption of spinal cord blood flow resulting from transient abdominal aortic occlusion may lead to degeneration of specific spinal cord neurons and to irreversible loss of neurological function. The alteration of nitric oxide/nitric oxide synthase (NO/NOS) pool occurring after ischemic insult may play a protective or destructive role in neuronal survival of affected spinal cord segments.2. In the present study, the spatiotemporal changes of NOS following transient ischemia were evaluated by investigating neuronal NOS immunoreactivity (nNOS-IR), reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) histochemistry, and calcium-dependent NOS (cNOS) conversion of [3H] l-arginine to [3H] l-citrulline.3. The greatest levels of these enzymes and activities were detected in the dorsal horn, which appeared to be most resistant to ischemia. In that area, the first significant increase in NADPHd staining and cNOS catalytic activity was found immediately after a 15-min ischemic insult.4. Increases in the ventral horn were observed later (i.e., after a 24-h reperfusion period). While the most intense increase in nNOS-IR was detected in surviving motoneurons of animals with a shorter ischemic insult (13 min), the greatest increase of cNOS catalytic activity and NADPHd staining of the endothelial cells was found after stronger insult (15 min).5. Given that the highest levels of nNOS, NADPHd, and cNOS were found in the ischemia-resistant dorsal horn, and nNOS-IR in surviving motoneurons, it is possible that NO production may play a neuroprotective role in ischemic/reperfusion injury. 相似文献
62.
Golubkina NA Papazyan TT 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2006,145(3-4):384-388
We studied the effect of egg mass of eight different avian species on Se distribution between egg components and the effect of incubation on Se accumulation by chicken eggshell and shell membrane. Eight groups of birds received a diet without Se supplementation. Unfertile eggs were collected after 35 days of feeding; yolk, albumen, shell and shell membrane were assayed separately for Se. All avian species studied showed identical Se concentration in yolk–albumen complex equal to 38.7 μg Se/100 g, reflecting a linear correlation between yolk–albumen mass and Se content. Shells and shell membrane Se accumulation showed quadratic correlation with the appropriate mass thus explaining unusually high Se concentration in ostrich shell and shell membrane, that reached values 1785 and 1904 μg Se/kg respectively. Incubation of fertile eggs decreased eggshell Se content, the effect being more expressed in eggs from hens fed sodium selenite compared to organic Se utilization (Sel-Plex). It was concluded that shell might be an additional Se source for an embryo. 相似文献
63.
Nadezda A. Brazhe Salim Abdali Oksana G. Luneva Eugenia Y. Parshina Georgy V. Maksimov 《Biophysical journal》2009,97(12):3206-3214
The article presents a noninvasive approach to the study of erythrocyte properties by means of a comparative analysis of signals obtained by surface-enhanced Raman spectroscopy (SERS) and resonance Raman spectroscopy (RS). We report step-by-step the procedure for preparing experimental samples containing erythrocytes in their normal physiological environment in a mixture of colloid solution with silver nanoparticles and the procedure for the optimization of SERS conditions to achieve high signal enhancement without affecting the properties of living erythrocytes. By means of three independent techniques, we demonstrate that under the proposed conditions a colloid solution of silver nanoparticles does not affect the properties of erythrocytes. For the first time to our knowledge, we describe how to use the SERS-RS approach to study two populations of hemoglobin molecules inside an intact living erythrocyte: submembrane and cytosolic hemoglobin (Hbsm and Hbc). We show that the conformation of Hbsm differs from the conformation of Hbc. This finding has an important application, as the comparative study of Hbsm and Hbc could be successfully used in biomedical research and diagnostic tests. 相似文献
64.
65.
Increased levels of “ROS” cause oxidative stress and are believed to play a key role in the development of age‐related diseases and mammalian aging, e.g. through the oxidation of residues, at or close to, the protein surface. In this study, we have investigated the effects of ROS on tryptophan residues in alpha skeletal actin and troponin I (fast skeletal muscle isoform) using an established rat model of acute oxidative stress induced by X‐ray irradiation. In the control samples (no oxidative stress), the single Trp residue of troponin I (position 161) and the four tryptophan residues present in actin (positions 79, 86, 340, and 356) were only oxidized at very low levels. Post‐irradiation, the level of oxidized versions increased for most positions within 3 h. Tryptophan residues located inside the proteins, however, required longer time periods. Based on the increment masses of the tryptophan positions calculated from the b‐ and y‐ion series of the tandem mass spectra, the following oxidation products of tryptophan were detected: kynurenine; oxolactone; hydroxytryptophan or oxindolylalanine (isobaric); hydroxykynurenine; dioxindolylalanine, N‐formylkynurenine or dihydroxytryptophan (all three isobaric); and hydroxyl‐N‐formylkynurenine, with mass gains relative to tryptophan of 4, 14, 16, 20, 32, and 48 u, respectively. Despite a partial recovery after 24 h, the degree of oxidation of all oxidized versions was still higher than in the control samples. 相似文献
66.
Alexandra S. Kuzmich Sergey N. Fedorov Valeria V. Shastina Larisa K. Shubina Oleg S. Radchenko Nadezda N. Balaneva Maxim E. Zhidkov Joo-In Park Jong Y. Kwak Valentin A. Stonik 《Bioorganic & medicinal chemistry》2010,18(11):3834-3840
3- and 10-Bromofascaplysins was previously found to possess cytotoxic activity. In this study, we investigated their cancer preventive and proapoptotic properties. These effects were tested on mouse skin epidermal JB6 P+ Cl41 cell line, its stable transfectants, and human tumor HL-60, THP-1, SNU-C4, SK-MEL-28, DLD-1, MDA-MB-231, and HeLa cells using a variety of assessments, including a cell viability (MTS) assay, flow cytometry, anchorage-independent soft agar assay, luciferase assay, mitochondrial permeability assay, and Western blotting. 3- and 10-Bromofascaplysins were effective at submicromolar concentrations as the anticancer agents, which exerted their action, at least in part, through the induction of caspase-8, -9, -3-dependent apoptosis. 相似文献
67.
de Bello Cioffi M Sánchez A Marchal JA Kosyakova N Liehr T Trifonov V Bertollo LA 《Genetica》2011,139(8):1065-1072
The wolf fish Hoplias malabaricus includes well differentiated sex systems (XY and X1X2Y in karyomorphs B and D, respectively), a nascent XY pair (karyomorph C) and not recognized sex chromosomes (karyomorph A).
We performed the evolutionary analysis of these sex chromosomes, using two X chromosome-specific probes derived by microdissection
from the XY and X1X2Y sex systems. A putative-sex pair in karyomorph A was identified, from which the differentiated XY system was evolved, as
well as the clearly evolutionary relationship between the nascent XY system and the origin of the multiple X1X2Y chromosomes. The lack of recognizable signals on the sex chromosomes after the reciprocal cross-FISH experiments highlighted
that they evolved independently from non-homologous autosomal pairs. It is noteworthy that these distinct pathways occur inside
the same nominal species, thus exposing the high plasticity of sex chromosome evolution in lower vertebrates. Possible mechanisms
underlying this sex determination liability are also discussed. 相似文献
68.
Gervas Polina Molokov Aleksey Schegoleva Anastasia Kiselev Artem Babyshkina Nataliya Pisareva Lubov Tyukalov Yury Choynzonov Evgeny Cherdyntseva Nadezda 《Molecular biology reports》2020,47(7):5315-5321
Molecular Biology Reports - In accordance with the Asian BRCA Consortium data, there is a significant difference in incidence rate of breast cancer depending on age, as well as spectrum and... 相似文献
69.
Microinjection into cells and embryos is a common technique that is used to study a wide range of biological processes. In this method a small amount of treatment solution is loaded into a microinjection needle that is used to physically inject individual immobilized cells or embryos. Despite the need for initial training to perform this procedure for high-throughput delivery, microinjection offers maximum efficiency and reproducible delivery of a wide variety of treatment solutions (including complex mixtures of samples) into cells, eggs or embryos. Applications to microinjections include delivery of DNA constructs, mRNAs, recombinant proteins, gain of function, and loss of function reagents. Fluorescent or colorimetric dye is added to the injected solution to enable instant visualization of efficient delivery as well as a tool for reliable normalization of the amount of the delivered solution. The described method enables microinjection of 100-400 sea urchin zygotes within 10-15 min. 相似文献
70.
Kummer S Jeruschke S Wegerich LV Peters A Lehmann P Seibt A Mueller F Koleganova N Halbenz E Schmitt CP Bettendorf M Mayatepek E Gross-Weissmann ML Oh J 《PloS one》2011,6(11):e27457