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1.
Syndecan-4 is a heparan sulfate-carrying core protein that has been directly implicated in fibroblast growth factor 2 (FGF2) signaling. Recent studies have suggested that many signaling proteins localize to the raft compartment of the plasma cell membrane. To establish whether syndecan-4 is present in the raft compartment, we have studied the distribution of the core protein and an Fc receptor (FcR)-syndecan-4 chimera prior to and following clustering with FGF2 or antibodies. Whereas unclustered syndecan-4 was present predominantly in the non-raft membrane compartment, clustering induced extensive syndecan-4 redistribution to the rafts as demonstrated by the sucrose gradient centrifugation and life confocal microscopy. Although syndecan-4 and caveolin-1 moved in tandem, syndecan-4 was not present in caveolae, a major subset of raft compartments. We conclude that syndecan-4 clustering induces its redistribution to the non-caveolae raft compartment. This process may play an important role in syndecan-4-mediation of FGF2 signaling. 相似文献
2.
Ilia Levitin Marina Tsikalova Natalia Sazikova Vladimir Bakhmutov Zoya Starikova Aleksandr Yanovsky Yuri Struchkov 《Inorganica chimica acta》1998,270(1-2):169-176
Organocobalt(III) complexes with Schiff bases derived from a β-diketone bearing both an alkyl and an aryl group have been prepared. The template syntheses using benzoylacetone and ethylenediamine as complexing agents provide a route to alkylcobalt chelates with the corresponding tri- and tetradentate Schiff bases. However, if a β-diketone with two aryl groups, e.g. dibenzoylmethane, was employed as the starting ketoenol component, no organometallic products were detected; a new mixed-ligand ‘inorganic’ chelate of cobalt(II), [Co{O=C(Ph)CH=C(Ph)O}2(en)], was isolated instead. Its structure as well as that of one of the alkylcobalt complexes with a tridentate Schiff base composed of benzoylacetone and ethylenediamine have been established by X-ray techniques. The current scope of the template synthesis of alkylcobalt complexes with Schiff bases is summarized. 相似文献
3.
4.
S B Tkachenko 《Biulleten' eksperimental'no? biologii i meditsiny》1989,108(11):542-545
In acute experiments on cats with closed chest the author studied the influence of artificial ventilation of increased frequency or volume on the pulmonary edema degree, foam formation intensity, pulmonary gas exchange and the animals survival in experimental pulmonary edema caused by intravenous infusion of mixture fatty acids. It was shown, that artificial ventilation of increased frequencies or volumes in pulmonary edema reduces the increase of the pulmonary coefficient and edema liquid quantity at the beginning of edema and it does not become stronger in following stages. Artificial ventilation of increased regimes decreases the foam formation, increases survival of the animals, delays the arterial pressure decrease, improves the pulmonary gas exchange. Artificial ventilation of increased frequency is more effective then ventilation of increased volume decreases foam formation and improves gas exchange in the lungs. 相似文献
5.
6.
B I Tkachenko A A Nurmatov Iu A Kudriashov 《Biulleten' eksperimental'no? biologii i meditsiny》1987,104(9):285-288
Acute experiments on cats using perfusion of the innervated calf muscle and small intestinal vessels with self blood at a constant blood flow rate have established decreased sensitivity of vessels (cooled to 30 degrees C) to hypoxic stimulus effect (inhalation of 10% O2 in N2). The essence of the phenomenon consists in considerably smaller deviations of pre- and postcapillary resistance, capillary filtration coefficient, mean capillary pressure during simultaneous exposure to cold and hypoxia than during separate application of hypoxic or hypothermic stimuli. Organ distinctions in the degree and direction of changes in vascular resistance and metabolism have been observed. 相似文献
7.
Elena Iurova Evgenii Beloborodov Elizaveta Tazintseva Aleksandr Fomin Alexander Shutov Sergei Slesarev Yana Saenko Yury Saenko 《Journal of peptide science》2021,27(1)
Peptide toxins of arthropods are one of the potential sources of bioactive substances. Toxins are able to bind to calcium channels and block them. Ca2+ ions play an important role in many cell processes, in particular, in apoptosis. In this work, we study the effect of some arthropod toxins on intracellular processes associated with the induction of apoptosis. Synthetic analogs of U5‐scytotoxin‐Sth1a, ω‐hexatoxin‐Hv1a, ω‐theraphotoxin‐Hhn2a, and μ‐agatoxin‐Aa1a toxins—inhibitors of calcium L, P, and Q channels and sodium channels were used in the study. Apoptosis was induced by AC‐1001 H3 peptide. We study the effect of toxins on the level of apoptosis, ROS, mitochondrial potential, GSH, and ATP in CHO‐K1 cells. We show that all the tested toxins are able to dose dependently block the induction of apoptosis triggered by AC‐1001 H3 and reduce the level of natural apoptosis in CHO‐K1 cells. Cell incubation with apoptosis inducer AC‐1001 H3 in the presence and absence of toxins causes an increase in the intracellular concentrations of ROS, ATP, and mitochondrial potential and decreases the GSH concentration. The present study reveals the antiapoptotic effect of a number of arthropod peptide toxins. The toxins studied can represent a novel approach used in the treatment of pathologies associated with the activation of apoptotic mechanisms. 相似文献
8.
Ishtiaque Rashid Michal Hammel Aleksandr Sverzhinsky Miaw-Sheue Tsai John M. Pascal John A. Tainer Alan E. Tomkinson 《The Journal of biological chemistry》2021,297(2)
Tyrosyl DNA phosphodiesterase 1 (TDP1) and DNA Ligase IIIα (LigIIIα) are key enzymes in single-strand break (SSB) repair. TDP1 removes 3′-tyrosine residues remaining after degradation of DNA topoisomerase (TOP) 1 cleavage complexes trapped by either DNA lesions or TOP1 inhibitors. It is not known how TDP1 is linked to subsequent processing and LigIIIα-catalyzed joining of the SSB. Here we define a direct interaction between the TDP1 catalytic domain and the LigIII DNA-binding domain (DBD) regulated by conformational changes in the unstructured TDP1 N-terminal region induced by phosphorylation and/or alterations in amino acid sequence. Full-length and N-terminally truncated TDP1 are more effective at correcting SSB repair defects in TDP1 null cells compared with full-length TDP1 with amino acid substitutions of an N-terminal serine residue phosphorylated in response to DNA damage. TDP1 forms a stable complex with LigIII170–755, as well as full-length LigIIIα alone or in complex with the DNA repair scaffold protein XRCC1. Small-angle X-ray scattering and negative stain electron microscopy combined with mapping of the interacting regions identified a TDP1/LigIIIα compact dimer of heterodimers in which the two LigIII catalytic cores are positioned in the center, whereas the two TDP1 molecules are located at the edges of the core complex flanked by highly flexible regions that can interact with other repair proteins and SSBs. As TDP1and LigIIIα together repair adducts caused by TOP1 cancer chemotherapy inhibitors, the defined interaction architecture and regulation of this enzyme complex provide insights into a key repair pathway in nonmalignant and cancer cells. 相似文献
9.
Characteristic Features of EEG Spectral Characteristics in Persons with Deviant Sexual Behavior 总被引:1,自引:0,他引:1
The study was performed with participation of 59 right-handed men. The normal group consisted of 19 subjects, and 40 patients with organic brain lesions who had commited sexual offenses were divided into two groups: 19 patients with a diagnosis of paraphilia (pathology of sexual drive) made up the main test group, and 21 patients without such a diagnosis formed the control group. A monopolar EEG was recorded in 16 standard leads in the states of rest (eyes closed) and general activation (eyes open) and during presentation of cognitive tests. The following EEG features manifest in all the frequency ranges and functional states were revealed in the group of patients with paraphilias as compared to the control groups: a substantially increased level of interhemispheric coherence (ICoh) and increased spectral density in the posterotemporal area (T
5, T
6), a significantly decreased ICoh level between the F
3/4 and C
3/4 leads in the frontocentral area, and lower spectral densities in the leads Fp
2, C
4, and P
4. Analysis of reactions to loads presented showed that the general arousal in the group of patients with paraphilias was characterized by significantly greater shifts of EEG parameters associated with the desynchronization reaction (as compared to the control groups) and statistically significant disorders of interhemispheric interaction and EEG reactivity in the right hemisphere in the range during performance of a visuospatial (right-hemispheric) task. The results suggest the formation of a stationary activation focus in the right hemisphere with signs of involvement of the limbic structures in patients with paraphilias. 相似文献
10.
Application of 1% methol, which, along with cold, activates specific thermosensitive ionic channels, changes the number of functioning cold receptors on the skin of the forearm similarly to the cold exposure test; however, it does not affect the number of heat receptors and does not significantly change the threshold of cold sensation. Group variants of responses to menthol that indicate individual differences in the sensitivity of skin receptors to the effects of methol and cold have been found. The results obtained give grounds to suggest that, from the variant of response to menthol (a decrease, increase, or absence of changes in the number of functioning cold receptors 5 min after menthol application), it is possible to predict specific features of response to cold. 相似文献