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11.
Laís Reis-das-Mercês Tatiana Vinasco-Sandoval Rafael Pompeu Aline Cruz Ramos Ana K. M. Anaissi Samia Demachki Paulo Pimentel de Assumpo Amanda F. Vidal ndrea Ribeiro-dos-Santos Leandro Magalhes 《International journal of molecular sciences》2022,23(2)
Gastric cancer (GC) is the fifth most common type of cancer and the third leading cause of cancer death in the world. It is a disease that encompasses a variety of molecular alterations, including in non-coding RNAs such as circular RNAs (circRNAs). In the present study, we investigated hsa_circ_0000211, hsa_circ_0000284, hsa_circ_0000524, hsa_circ_0001136 and hsa_circ_0004771 expression profiles using RT-qPCR in 71 gastric tissue samples from GC patients (tumor and tumor-adjacent samples) and volunteers without cancer. In order to investigate the suitability of circRNAs as minimally invasive biomarkers, we also evaluated their expression profile through RT-qPCR in peripheral blood samples from patients with and without GC (n = 41). We also investigated the predicted interactions between circRNA-miRNA-mRNA and circRNA-RBP using the KEGG and Reactome databases. Overall, our results showed that hsa_circ_0000211, hsa_circ_0000284 and hsa_circ_0004771 presented equivalent expression profiles when analyzed by different methods (RNA-Seq and RT-qPCR) and different types of samples (tissue and blood). Further, functional enrichment results identified important signaling pathways related to GC. Thus, our data support the consideration of circRNAs as new, minimally invasive biomarkers capable of aiding in the diagnosis of GC and with great potential to be applied in clinical practice. 相似文献
12.
Identification of potential technologies for 1,4-Butanediol production using prospecting methodology
Ramon Geraldo Campos Silva Tatiana Felix Ferreira Élcio Ribeiro Borges 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(12):3057-3070
1,4-Butanediol (1,4-BDO) is a four-carbon diol used for industrial applications such as organic solvents, and the production of adhesives, fibers and polyurethanes. 1,4-BDO currently is produced through several petrochemical routes: hydrogenation of maleic anhydride, isomerization of propylene oxide, acetoxylation of butadiene, and the reaction between formaldehyde and acetylene. The current trends in 1,4-BDO production involve the utilization of renewable sources such as biomass. In this context, the present study aimed to identify promising technologies of 1,4-BDO production through prospecting methodology based on the analyses of patents and scientific article, describing the most relevant aspects of those emerging technologies. An increasing amount of 1,4-BDO production focused on biotechnological routes has been reported, with the US heavily involved in the development of new technologies. This study tracked three promising technologies which have potential for application in a biorefinery context because those processes involve (i) production of 1,4-BDO from sugars, classified herein as the biotechnological route; (ii) production of intermediates from sugar fermentation followed by catalytic conversion into 1,4-BDO, classified herein as the hybrid route, and (iii) furan/furfural conversion into 1,4-BDO. © 2020 Society of Chemical Industry 相似文献
13.
14.
Tatiana B. Eronina Valeriya V. Mikhaylova Natalia A. Chebotareva Kristina V. Tugaeva Boris I. Kurganov 《International journal of molecular sciences》2022,23(7)
Protein–protein interactions (PPIs) play an important role in many biological processes in a living cell. Among them chaperone–client interactions are the most important. In this work PPIs of αB-crystallin and glycogen phosphorylase b (Phb) in the presence of betaine (Bet) and arginine (Arg) at 48 °C and ionic strength of 0.15 M were studied using methods of dynamic light scattering, differential scanning calorimetry, and analytical ultracentrifugation. It was shown that Bet enhanced, while Arg reduced both the stability of αB-crystallin and its adsorption capacity (AC0) to the target protein at the stage of aggregate growth. Thus, the anti-aggregation activity of αB-crystallin increased in the presence of Bet and decreased under the influence of Arg, which resulted in inhibition or acceleration of Phb aggregation, respectively. Our data show that chemical chaperones can influence the tertiary and quaternary structure of both the target protein and the protein chaperone. The presence of the substrate protein also affects the quaternary structure of αB-crystallin, causing its disassembly. This is inextricably linked to the anti-aggregation activity of αB-crystallin, which in turn affects its PPI with the target protein. Thus, our studies contribute to understanding the mechanism of interaction between chaperones and proteins. 相似文献
15.
Vladimir Sukhorukov Alina Magnaeva Tatiana Baranich Anna Gofman Dmitry Voronkov Tatiana Gulevskaya Valeria Glinkina Sergey Illarioshkin 《International journal of molecular sciences》2022,23(18)
Accumulating data suggest that the brain undergoes various changes during aging. Among them are loss of both white and gray matter, neurons and synapses degeneration, as well as oxidative, inflammatory, and biochemical changes. The above-mentioned age-related features are closely related to autophagy and mitochondria. Therefore, we aimed to reveal the most peculiar morphological features of brain nervous tissue and to characterize the expression of autophagy and mitochondrial immunohistochemical biomarkers in neurons of different human brain zones during aging. Counting the number of neurons as well as Microtubule-associated proteins 1A/1B light chain 3B (LC3B), Heat shock protein 70 (HSP70), Lysosome-associated membrane protein type 2A (LAMP2A), Alpha subunit of ATP synthase (ATP5A), and Parkinson disease protein 7 (DJ1) immunohistochemical staining were performed on FFPE samples of human prefrontal cortex, corpus striatum, and hippocampus obtained from autopsy. Statistical analysis revealed a loss of neurons in the studied elderly group in comparison to the young group. When the expression of macroautophagy (LC3B), chaperon-mediated autophagy (HSP70, LAMP2A), and mitochondrial respiratory chain complex V (ATP5A) markers for the young and elderly groups were compared, the latter was found to have a significantly higher rate of optical density, whilst there was no significance in DJ1 expression. These findings, while preliminary, suggest that both autophagy and mitochondria are involved in neuronal maintenance during aging and could indicate their potential role in adaptive mechanisms that occur in aging. 相似文献
16.
The fullerene family, and especially C(60), has delighted the scientific community during the last 25 years with perspective applications in a wide variety of fields, including the biological and the biomedical domains. Several biomedical uses have been explored using water-soluble C(60)-derivatives. However, the employment of fullerenes for drug delivery is still at an early stage of development. The design and synthesis of multifunctionalized and multimodal C(60) systems able to cross the cell membranes and efficiently deliver active molecules is an attracting challenge that involves multidisciplinary strategies. Promising results have emerged in the last years, bringing fullerenes again to the front of interest. Herein, the state of the art of this emerging field is presented and illustrated with some of the most representative examples. 相似文献
17.
Ekaterina S. Lokteva Aleksey E. LazhkoElena V. Golubina Vadim V. TimofeevAlexander V. Naumkin Tatiana V. YagodovskayaSergey N. Gaidamaka Valery V. Lunin 《The Journal of Supercritical Fluids》2011,58(2):263-271
Carbonaceous deposits formation was established as the primary reason of Pd/TiO2 catalyst deactivation during reductive processing of CCl4 to form hydrodechlorination and oligomerization products. Three methods of carbonaceous deposits elimination were tested: (1) extraction by supercritical CO2, (2) oxidation by ozone in supercritical CO2, and (3) low-temperature glow-discharge oxygen plasma treatment. Synchronic thermal analysis confirms effective carbonaceous deposits removal during regeneration by ozone or low temperature glow-discharge oxygen plasma; by XPS deep oxidation of surface Pd after oxidative treatment (by ozone or oxygen plasma) was found. Thus H2 reduction was proposed as the second step making possible full regeneration of initial catalytic activity of Pd/TiO2. 相似文献
18.
M. E. Henry Bergmann Tatiana Iourtchouk Johanna Rollin 《Journal of Applied Electrochemistry》2011,41(9):1109-1123
Bromide electrolysis was carried out on laboratory-scale cells in the range of 1–1,005 mg [Br−] dm−3 using boron-doped diamond (BDD) anodes. These studies were part of fundamental research activities on drinking water electrolysis
for disinfection. Synthetic water systems were mostly used in the experiments, which varied the temperature between 5 and
30 °C, the current density between 50 and 700 A m−2, and the rotation rate of the rotating anode between 100 and 500 rpm (laminar regime). Hypobromite and bromate were found
as by-products, as expected. Bromite was not detected. Higher bromate levels were formed at higher current density, but no
clear relationship was observed between bromate concentration and the rotation rate or temperatures between 5 and 30 °C. Bromate
yields higher than 90% were found at higher charge passed. Perbromate was found as a new potential synthesis or disinfection
by-product (DBP), but no perbromate was detected at the lowest bromide concentrations and under drinking water conditions.
The perbromate yield was about 1%, and somewhat lower when bromate was used as a starting material instead of bromide. At
a temperature of 5 °C more perbromate was detected compared with experiments at 20°. Approximately 20 times more perchlorate
was formed compared with perbromate formation in the presence of chloride ions of equimolar concentration. State of mechanistic
considerations is presented and a mechanism for perbromate formation is proposed. The reaction from bromate to perbromate
was found to be limited that is in contrast to the earlier studied chlorate-to-perchlorate conversion. In the measured concentration
range, reduction processes at the mixed oxide cathode showed a much higher impact on the resulting concentration for perbromate
than for bromate. 相似文献
19.
Alexander S. Goryashchenko Maria G. Khrenova Anna A. Bochkova Tatiana V. Ivashina Leonid M. Vinokurov Alexander P. Savitsky 《International journal of molecular sciences》2015,16(7):16642-16654
This article describes the genetically encoded caspase-3 FRET-sensor based on the terbium-binding peptide, cleavable linker with caspase-3 recognition site, and red fluorescent protein TagRFP. The engineered construction performs two induction-resonance energy transfer processes: from tryptophan of the terbium-binding peptide to Tb3+ and from sensitized Tb3+ to acceptor—the chromophore of TagRFP. Long-lived terbium-sensitized emission (microseconds), pulse excitation source, and time-resolved detection were utilized to eliminate directly excited TagRFP fluorescence and background cellular autofluorescence, which lasts a fraction of nanosecond, and thus to improve sensitivity of analyses. Furthermore the technique facilitates selective detection of fluorescence, induced by uncleaved acceptor emission. For the first time it was shown that fluorescence resonance energy transfer between sensitized terbium and TagRFP in the engineered construction can be studied via detection of microsecond TagRFP fluorescence intensities. The lifetime and distance distribution between donor and acceptor were calculated using molecular dynamics simulation. Using this data, quantum yield of terbium ions with binding peptide was estimated. 相似文献
20.
Dr. Donald R. Griffin Jacob Borrajo Dr. Allyson Soon Giovanny F. Acosta‐Vélez Victor Oshita Nicole Darling Dr. Julia Mack Prof. Thomas Barker Prof. M. Luisa Iruela‐Arispe Prof. Tatiana Segura 《Chembiochem : a European journal of chemical biology》2014,15(2):233-242
The ability to design artificial extracellular matrices as cell‐instructive scaffolds has opened the door to technologies capable of studying the fate of cells in vitro and to guiding tissue repair in vivo. One main component of the design of artificial extracellular matrices is the incorporation of biochemical cues to guide cell phenotype and multicellular organization. The extracellular matrix (ECM) is composed of a heterogeneous mixture of proteins that present a variety of spatially discrete signals to residing cell populations. In contrast, most engineered ECMs do not mimic this heterogeneity. In recent years, photo‐deprotection has been used to spatially immobilize signals. However, this approach has been limited mostly to small peptides. Here we combine photo‐deprotection with enzymatic reaction to achieve spatially controlled immobilization of active bioactive signals that range from small molecules to large proteins. A peptide substrate for transglutaminase factor XIII (FXIIIa) was caged with a photo‐deprotectable group, which was then immobilized to the bulk of a cell‐compatible hydrogel. With focused light, the substrate can be deprotected and used to immobilize patterned bioactive signals. This approach offers an innovative strategy to immobilize delicate bioactive signals, such as growth factors, without loss of activity and enables in situ cell manipulation of encapsulated cells. 相似文献