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11.
The transient absorbance increase induced by ADP in phosphate-loaded respiring mitochondria becomes stable and greatly amplified by inhibitors of phosphate transport. The absorbance changes are sensitive to oligomycin and to aurovertin and their extent is proportional to the amount of ADP added. Simultaneously with the ADP-dependent increase in absorbance the inorganic phosphate and K+-ion content of the matrix decreases. It is concluded that the optical change reflects contraction of the matrix compartment secondary to intramitochondrial solute changes. 相似文献
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Attila Vnyols Boena Muszyska Bayar Chuluunbaatar Joanna Gdula‐Argasiska Katarzyna Kaa Judit Hohmann 《化学与生物多样性》2020,17(9)
Hypholoma lateritium is an edible macrofungus with a common distribution in Europe, North America, and the Far East. The aim of this study was to investigate the potential anti‐inflammatory effects of H. lateritium extracts and its isolated steroids: fasciculic acid B, fasciculol E, fasciculol C, lanosta‐7,9(11)‐diene‐12β,21α‐epoxy‐2α,3β,24β,25‐tetraol, fasciculol F, and demethylincisterol A2. Organic (hexane, chloroform and 50 % methanol) and water extracts of H. lateritium were subjected to in vitro assays to determine pro‐inflammatory protein levels, such as cyclooxygenase‐2 (COX‐2), cytosolic prostaglandin E2 synthase (cPGES), and antioxidant nuclear factor (erythroid‐derived 2)‐like 2 (Nrf2). Fungal extracts demonstrated significant activities on pro‐inflammatory protein levels with minor differences among the activities of the fractions of different polarities. All the compounds proved to exert notable inhibitory properties on COX‐2 and were capable to stimulate the Nrf2 pathway. Fungal extracts and the compounds exerted no cytotoxic activities on RAW 264.7 cells. 相似文献
14.
Safak Kalindamar Adef O. Kordon Hossam Abdelhamed Wei Tan Lesya M. Pinchuk Attila Karsi 《Cellular microbiology》2020,22(3)
Edwardsiella ictaluri is a Gram‐negative facultative anaerobe that can survive inside channel catfish phagocytes. E. ictaluri can orchestrate Type VI Secretion System (T6SS) for survival in catfish macrophages. evpP encodes one of the T6SS translocated effector proteins. However, the role of evpP in E. ictaluri is still unexplored. In this work, we constructed an E. ictaluri evpP mutant (EiΔevpP) and assessed its survival under complement and oxidative stress. Persistence of EiΔevpP in catfish as well as attachment and invasion in catfish macrophage and ovary cells were determined. Further, virulence of EiΔevpP in catfish and apoptosis it caused in macrophages were explored. EiΔevpP behaved same as wild type (EiWT) under complement and oxidative stress in complex media, whereas oxidative stress affected mutant's survival significantly in minimal media (p < .05). Persistence of EiΔevpP in live catfish and uptake and survival inside peritoneal macrophages were similar. The attachment and invasion capabilities of EiΔevpP in catfish ovary cells were significantly less than that of EiWT (p < .05). Although EiΔevpP showed reduced attenuation in catfish, causing decreased catfish mortality compared with EiWT (44.73% vs. 67.53%), this difference was not significant. The apoptosis assay using anterior kidney macrophages indicated that the number of live macrophages exposed to EiΔevpP was significantly higher compared with EiWT exposed macrophages at 24‐hr post‐treatment (p < .05). However, there were no significant differences in the early and late apoptosis. Remarkably, necrosis in EiΔevpP exposed macrophages was significantly less than that of EiWT exposed macrophages at 24 hr (p < .05). Our results demonstrated that evpP is required for colonisation of catfish ovary cells and increased apoptosis and necrosis in anterior kidney macrophages. 相似文献
15.
Lajos Attila Papp Mohammadhassan Foroughbakhshfasaei Béla Fiser Péter Horváth Eszter Kiss Khaled Sekkoum Árpád Gyéresi Gabriel Hancu Béla Noszál Zoltán-István Szabó Gergő Tóth 《Chirality》2020,32(2):158-167
A direct HPLC method was developed for the enantioseparation of pantoprazole using macrocyclic glycopeptide-based chiral stationary phases, along with various methods to determine the elution order without isolation of the individual enantiomers. In the preliminary screening, four macrocyclic glycopeptide-based chiral stationary phases containing vancomycin (Chirobiotic V), ristocetin A (Chirobiotic R), teicoplanin (Chirobiotic T), and teicoplanin-aglycone (Chirobiotic TAG) were screened in polar organic and reversed-phase mode. Best results were achieved by using Chirobiotic TAG column and a methanol-water mixture as mobile phase. Further method optimization was performed using a face-centered central composite design to achieve the highest chiral resolution. Optimized parameters, offering baseline separation (resolution = 1.91 ± 0.03) were as follows: Chirobiotic TAG stationary phase, thermostated at 10°C, mobile phase consisting of methanol/20mM ammonium acetate 60:40 v/v, and 0.6 mL/min flow rate. Enantiomer elution order was determined using HPLC hyphenated with circular dichroism (CD) spectroscopy detection. The online CD signals of the separated pantoprazole enantiomers at selected wavelengths were compared with the structurally analogous esomeprazole enantiomer. For further verification, the inline rapid, multiscan CD signals were compared with the quantum chemically calculated CD spectra. Furthermore, docking calculations were used to investigate the enantiorecognition at molecular level. The molecular docking shows that the R-enantiomer binds stronger to the chiral selector than its antipode, which is in accordance with the determined elution order on the column—S- followed by the R-isomer. Thus, combined methods, HPLC-CD and theoretical calculations, are highly efficient in predicting the elution order of enantiomers. 相似文献
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Enrique Murillo Attila Agócs Veronika Nagy Sándor Balázs Király Tibor Kurtán Eunice Molinar Toribio Johant Lakey-Beitia József Deli 《Chirality》2020,32(5):579-587
Two new carotenoids, sapotexanthin 5,6-epoxide and sapotexanthin 5,8-epoxide, have been isolated from the ripe fruits of red mamey (Pouteria sapota). Sapotexanthin 5,6-epoxide was also prepared by partial synthesis via epoxidation of sapotexanthin, and the (5R,6S) and (5S,6R) stereoisomers were identified by high-performance liquid chromatography–electronic circular dichroism (HPLC-ECD) analysis. Spectroscopic data of the natural and semisynthetic derivatives obtained by acid-catalyzed rearrangement of cryptocapsin 5,8-epoxide stereoisomers were compared for structural elucidation. 相似文献
17.
Trigonostemons G and H, two novel dimeric dinorditerpenoids, were isolated from the stem barks of Trigonostemon chinensis. Their planar structures and relative configurations were established by extensive analysis of spectroscopic data. Trigonostemons G and H possess a homodimeric biaryl skeleton obtained from two rearranged chiral nonracemic abietane-type dinorditerpenes through an axially chiral biaryl 11,11′-linkage. Torsional scan and computation of the transition states were carried out to estimate the rotational energy barrier, and the axial chirality (aS) was determined by time-dependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations. The positive n-π* ECD transitions of the isolated carbonyl chromophore above 300 nm could be used to determine the central chirality of trigonostemon G independently by ECD calculations of the diastereomers. 相似文献
18.
Júlia Domján Annamária Fricska Lajos Madarász Martin Gyürkés Ákos Köte Attila Farkas Panna Vass Csaba Fehér Balázs Horváth Kálmán Könczöl Hajnalka Pataki Zsombor Kristóf Nagy György János Marosi Edit Hirsch 《Biotechnology progress》2020,36(6):e3052
The use of Process Analytical Technology tools coupled with chemometrics has been shown great potential for better understanding and control of mammalian cell cultivations through real-time process monitoring. In-line Raman spectroscopy was utilized to determine the glucose concentration of the complex bioreactor culture medium ensuring real-time information for our process control system. This work demonstrates a simple and fast method to achieve a robust partial least squares calibration model under laboratory conditions in an early phase of the development utilizing shake flask and bioreactor cultures. Two types of dynamic feeding strategies were accomplished where the multi-component feed medium additions were controlled manually and automatically based on the Raman monitored glucose concentration. The impact of these dynamic feedings was also investigated and compared to the traditional bolus feeding strategy on cellular metabolism, cell growth, productivity, and binding activity of the antibody product. Both manual and automated dynamic feeding strategies were successfully applied to maintain the glucose concentration within a narrower and lower concentration range. Thus, besides glucose, the glutamate was also limited at low level leading to reduced production of inhibitory metabolites, such as lactate and ammonia. Consequently, these feeding control strategies enabled to provide beneficial cultivation environment for the cells. In both experiments, higher cell growth and prolonged viable cell cultivation were achieved which in turn led to increased antibody product concentration compared to the reference bolus feeding cultivation. 相似文献
19.
Rka Fekete Judit Bdis Bence Fülp Kristf Süveges Renta Urgyn Tams Malkcs Orsolya Vincze Luís Silva Attila Molnr V. 《Ecology and evolution》2020,10(23):13236
Seminatural habitats are declining throughout the world; thus, the role of small anthropogenic habitats in the preservation of plants is becoming increasingly appreciated. Here, we surveyed the orchid flora of roadside verges in five Central European countries (Austria, Hungary, Romania, Slovakia, and Slovenia) and tested how the surrounding landscape matrix affects the overall number of species and individuals, and also different functional groups of orchids. We found more than 2,000 individuals of 27 orchid species during our surveys. According to our results, the increasing coverage of agricultural and urban areas negatively affects both the number of orchid species and individuals on roadsides. Our study further suggests that differences in the surrounding habitats affect which species are found on roadsides, since the increasing coverage of grasslands or forested areas around orchid occurrences had a significant positive effect on the number of grassland or forest‐dwelling species and individuals, respectively. Most variance in orchid numerosity and diversity was explained by the cover of the suitable habitat types of the respective taxa in the surrounding landscape of the sampling points. This highlights the importance of roadsides acting as refugia for numerous species and valuable plant communities as well as in supporting biodiversity in general. 相似文献
20.
Parker Camille Zhao Jing Pearce David A. Kovács Attila D. 《Archives of microbiology》2021,203(1):85-96
Archives of Microbiology - Accumulated evidence indicates that the gut microbiota affects brain function and may be altered in neurological diseases. In this study, we analyzed the gut microbiota... 相似文献