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101.
102.
Molecular Biology - Neuroinflammation plays a key role in the pathogenesis of neurodegenerative diseases. Microglial cells are the main immune cells of the central nervous system. On exposure to... 相似文献
103.
In neurons of the rat dorsal root ganglia (DRG), using a patch-clamp technique in the whole-cell configuration, we studied
the characteristics of calcium channels activated by depletion of the ryanodine-sensitive calcium stores of the endoplasmic
reticulum. Current-voltage (I-V) relationships of these store-operated calcium channels were obtained by subtraction of the
integral I-V characteristics after application of caffeine from the integral I-V characteristics of calcium channels in the
control. Currents through store-operated calcium channels could be induced by application of a series of hyperpolarization
current pulses to the cell under conditions of replacement of a calcium-free solution containing caffeine by a caffeine-free
solution containing 2 mM Ca2+. In this case, the following two main conditions were abserved: Voltage-operated calcium channels were inactivated, while
a gradient of the electrochemical potential for calcium ions was increased, which made easier passing of these currents through
store-operated calcium channels. Therefore, we found that in DRG neurons, despite the presence of great numbers of both voltage-operated
and receptor-dependent calcium channels, one more mechanism underlying the entry of calcium through store-operated channels
does exist.
Neirofiziologiya/Neurophysiology, Vol. 39, No. 3, pp. 195–200, May–June, 2007. 相似文献
104.
A. R. Kotovskaya M. I. Koloteva V. Yu. Luk’yanuk G. P. Stepanova L. M. Filatova S. P. Builov A. F. Zhernavkov L. L. Kondratuk 《Human physiology》2010,36(7):871-876
Analysis of alterations in the cardiac activity on the basis of electrocardiographic (ECG) findings in 29 cosmonauts of flight
and ground professions aged from 29 to 61 years after 34 short (8–30 days) space flights (SFs) between 1982 and 2006 has been
carried out. The ECG data at the stage of clinical selection, clinical-physiological examination (CPE) before a SF, at the
stage of the launch of a spacecraft (SC) into orbit and its landing on Earth and at the stage of postflight CPE have been
analyzed. The analysis of cardiac activity parameters on the basis of ECG data at different stages of observations has led
to the identification of three groups of cosmonauts. There were no significant changes or negative tendencies in the alteration
of ECG data in the first group (55.2% of the total number of cosmonauts) during the observation period from selection to the
end of the SF. The changes that later became more pronounced during the landing on Earth and were retained during postflight
CPE have been found in the second group of cosmonauts (in 34.5% cases) at the time of selection and preflight CPE. Considerable
disturbances in cardiac activity that are dangerous for human health have been found in ECGs in the third group (10.3%) during
the descent from orbit. The data from the study are the first step in the investigation of possible medical risks for the
development and improvement of requirements for the medical selection of crews and the admission of subjects with partial
health insufficiency on SFs. 相似文献
105.
106.
107.
Paola Barraja Virginia Spanò Diana Patrizia Anna Carbone Girolamo Cirrincione Daniela Vedaldi Alessia Salvador Giampietro Viola Francesco Dall’Acqua 《Bioorganic & medicinal chemistry letters》2009,19(6):1711-1714
A convenient synthesis of the pyrano[2,3-e]isoindol-2-one ring system, an heteroanalogue of angelicin, is reported. Our synthetic approach consists of the annelation of the pyran ring on the isoindole moiety using 5-dialkylamino- or 5-hydroxymethylene intermediates as building blocks. The photoantiproliferative activity of the new derivatives was studied. Some of them bearing the benzyl group at the 8 position were active with IC50 in the micromolar range. Cell cytotoxicity involves apoptosis, alteration of cell cycle profile and membrane photodamage. 相似文献
108.
Kateřina Kuželová Dana Grebeňová Michaela Pluskalová Daniel Kavan Petr Halada Zbyněk Hrkal 《Journal of cellular biochemistry》2009,106(4):673-681
The proteins of 14‐3‐3 family are substantially involved in the regulation of many biological processes including the apoptosis. We studied the changes in the expression of five 14‐3‐3 isoforms (β, γ, ε, τ, and ζ) during the apoptosis of JURL‐MK1 and K562 cells. The expression level of all these proteins markedly decreased in relation with the apoptosis progression and all isoforms underwent truncation, which probably corresponds to the removal of several C‐terminal amino acids. The observed 14‐3‐3 modifications were partially blocked by caspase‐3 inhibition. In addition to caspases, a non‐caspase protease is likely to contribute to 14‐3‐3's cleavage in an isoform‐specific manner. While 14‐3‐3 γ seems to be cleaved mainly by caspase‐3, the alternative mechanism is essentially involved in the case of 14‐3‐3 τ, and a combined effect was observed for the isoforms ε, β, and ζ. We suggest that the processing of 14‐3‐3 proteins could form an integral part of the programmed cell death or at least of some apoptotic pathways. J. Cell. Biochem. 106: 673–681, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
109.
Man Il Kim Jee Yeon Baek Min Jee Kim Heon Cheon Jeong Ki-Gyoung Kim Chang Hwan Bae Yeon Soo Han Byung Rae Jin Iksoo Kim 《Molecules and cells》2009,28(4):347-363
The 15,389-bp long complete mitogenome of the endangered red-spotted apollo butterfly, Parnassius bremeri (Lepidoptera: Papilionidae) was determined in this study. The start codon for the COI gene in insects has been extensively discussed, and has long remained a matter of some controversy. Herein, we propose that the CGA (arginine) sequence functions as the start codon for the COI gene in lepidopteran insects, on the basis of complete mitogenome sequences of lepidopteran insects, including P. bremeri, as well as additional sequences of the COI start region from a diverse taxonomic range of lepidopteran species (a total of 53 species from 15 families). In our extensive search for a tRNA-like structure in the A+T-rich region, one tRNATrp-like sequence and one tRNALeu (UUR)-like sequence were detected in the P. bremeri A+T-rich region, and one or more tRNA-like structures were detected in the A+T-rich region of the majority of other sequenced lepidopteran insects, thereby indicating that such features occur frequently in the lepidopteran mitogenomes. Phylogenetic analysis using the concatenated 13 amino acid sequences and nucleotide sequences of PCGs of the four macrolepidopteran superfamilies together with the Tortricoidea and Pyraloidea resulted in the successful recovery of a monophyly of Papilionoidea and a monophyly of Bombycoidea. However, the Geometroidea were unexpectedly identified as a sister group of the Bombycoidea, rather than the Papilionoidea. 相似文献
110.
In the cultures of the alga Chlamydomonas reinhardtii, division rhythms of any length from 12 to 75 h were found at a range of different growth rates that were set by the intensity
of light as the sole source of energy. The responses to light intensity differed in terms of altered duration of the phase
from the beginning of the cell cycle to the commitment to divide, and of the phase after commitment to cell division. The
duration of the pre-commitment phase was determined by the time required to attain critical cell size and sufficient energy
reserves (starch), and thus was inversely proportional to growth rate. If growth was stopped by interposing a period of darkness,
the pre-commitment phase was prolonged corresponding to the duration of the dark interval. The duration of the post-commitment
phase, during which the processes leading to cell division occurred, was constant and independent of growth rate (light intensity)
in the cells of the same division number, or prolonged with increasing division number. It appeared that different regulatory
mechanisms operated through these two phases, both of which were inconsistent with gating of cell division at any constant
time interval. No evidence was found to support any hypothetical timer, suggested to be triggered at the time of daughter
cell release. 相似文献