194 research outputs found
A chiral molecular cage comprising diethynylallenes and N‐heterotriangulenes for enantioselective recognition
Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGChirality, a characteristic tool of molecular recognition in nature, is often a complement of redox active systems. Scientists, in their eagerness to mimic such sophistication, have designed numerous chiral systems based on molecular entities with cavities, such as macrocycles and cages. In an attempt to combine chirality and redox-active species, in this contribution we report the synthesis and detailed characterization of a chiral shape-persistent molecular cage based on the combination of enantiopure diethynylallenes and electron-rich bridged triarylamines, also known as N-heterotriangulenes. Its ability for chiral recognition in solution was revealed through UV/vis titrations with enantiopure helicenes.Agencia Estatal de Investigación | Ref. CTQ2017-85919-RDeutsche Forschungsgemeinschaft | Ref. 182849149Deutsche Forschungsgemeinschaft | Ref. 281029004-SFB1249FP7 People: Marie-Curie Actions | Ref. PIRSES-GA-2012-318930-InTechSEXunta de Galicia | Ref. ED431C 2017/7
Cysteine peptidases and their inhibitors in breast and genital cancer.
Cysteine proteinases and their inhibitors probably play the main role in carcinogenesis and metastasis. The metastasis process need external proteolytic activities that pass several barriers which are membranous structures of the connective tissue which includes, the basement membrane of blood vessels. Activities of the proteinases are regulated by endogenous inhibitors and activators. The imbalance between cysteine proteinases and cystatins seems to be associated with an increase in metastatic potential in some tumors. It has also been reported that proteinase inhibitors, specific antibodies for these enzymes and inhibition of the urokinase receptor may prevent cancer cell invasion. Some proteinase inhibitor could serve as agents for cancer treatment
Changes in cognitive processes and coping strategies precede changes in symptoms during cognitive therapy for posttraumatic stress disorder
Theories of posttraumatic stress disorder (PTSD) highlight the role of cognitive and behavioral factors in its development, maintenance, and treatment. This study investigated the relationship between changes in factors specified in Ehlers and Clark's (2000) model of PTSD and PTSD symptom change in 217 patients with PTSD who were treated with cognitive therapy for PTSD (CT-PTSD) in routine clinical care. Bivariate latent change score models (LCSM) of session-by-session changes in self-report measures showed that changes in PTSD symptoms were preceded by changes in negative appraisals, flashback characteristics of unwanted memories, safety behaviours, and unhelpful responses to intrusions, but not vice versa. For changes in trauma memory disorganization and PTSD symptoms we found a bidirectional association. This study provides evidence that cognitive and behavioral processes proposed in theoretical models of PTSD play a key role in driving symptom improvement during CT-PTSD
Stark broadening of B IV lines for astrophysical and laboratory plasma research
Stark broadening parameters for 36 multiplets of B IV have been calculated
using the semi-classical perturbation formalism. Obtained results have been
used to investigate the regularities within spectral series and temperature
dependence.Comment: 8 pages, 6 figures, 1 table, in press in Advances in Space Researc
Stark broadening of B IV spectral lines
Stark broadening parameters for 157 multiplets of helium like boron (B IV)
have been calculated using the impact semiclassical perturbation formalism.
Obtained results have been used to investigate the regularities within spectral
series. An example of the influence of Stark broadening on B IV lines in DO
white dwarfs is given.Comment: 6 pages, 2 figure
Human stem cell-derived retinal epithelial cells activate complement via collectin 11 in response to stress
Abstract Age-related macular degeneration (AMD) is a major cause of blindness and is associated with complement dysregulation. The disease is a potential target for stem cell therapy but success is likely to be limited by the inflammatory response. We investigated the innate immune properties of human induced-pluripotent stem cell (iPSC)-derived RPE cells, particularly with regard to the complement pathway. We focused on collectin-11 (CL-11), a pattern recognition molecule that can trigger complement activation in renal epithelial tissue. We found evidence of constitutive and hypoxia-induced expression of CL-11 in iPS-RPE cells, and in the extracellular fluid. Complement activation on the cell surface occurred in conjunction with CL-11 binding. CL-11 has been shown to activate inflammatory responses through recognition of L-fucose, which we confirmed by showing that fucosidase-treated cells, largely, failed to activate complement. The presence of CL-11 in healthy murine and human retinal tissues confirmed the biological relevance of CL-11. Our data describe a new trigger mechanism of complement activation that could be important in disease pathogenesis and therapeutic interventions
Efikasnost primene preparata na bazi zeolita u obrocima jagnjadi u tovu
The paper presents results of investigations of the effect of a preparation based on natural zeolite on production results of fattening lambs. The experiment was performed on two groups of lamps (control – K and experimental – O), 15 animals per group, and for a duration of 90 days. The diet ration consisted of sheeps’ milk, a compound mix for fattening lambs, and meadow hay. Lambs of the experimental group, contrary to those of the control group were administered preparations based on natural zeolite. The preparation Min-a-Zel® S (in the form of 25% suspension) was administered to lambs from birth until the 14th day of life, directly into the mouth, once daily (before the morning meal), 10 ml each. Min-a-Zel Plus was administered starting from the 15th day by adding it to the fodder mix (0.5%). Feeding was ad libitum. The average body mass of lambs at the end of the experiment, according to the sequence of treatments (K:O), was 24.40:26.94 kg (P<0.01). The daily groth of the lambs, during the course of the experiment, was 229:256 g, and was 27 g or 11.79% higher (P<0.01) in the experimental group. The experimental group had better utilization of dry matter, proteins and energy, which indicates that the use of a preparation based on natural zeolite in the diet of fattening lambs is justified.U radu su prikazani rezultati istraživanja o uticaju preparata na bazi prirodnog zeolita na proizvodne rezultate jagnjadi u tovu. Ogled je izveden na dve grupe jagnjadi (kontrolna – K i ogledna – O), po 15 grla, u trajanju od 90 dana. Obrok se sastojao od ovčijeg mleka, krmne smeše za tov jagnjadi i livadskog sena. Jagnjad ogledne grupe, za razliku od kontrolne, dobijala su preparate na bazi prirodnog zeolita. Preparat Min-a-Zel®S (u obliku 25% suspenzije) jagnjad je dobijala od rođenja do 14. dana života, direktno u usta, jednom dnevno, (pre jutarnjeg napajanja), po 10 ml. Min-a-Zel® Plus im se davao počev od 15. dana uzrasta na taj način {to je bio je uključen u krmnu smešu (0,5%). Ishrana je bila po volji. Prosečna telesna masa jagnjadi na kraju ogleda, prema redosledu tretmana (K:O), bila je 24,40:26,94 kg (P<0,01). Dnevni prirast jagnjadi, tokom ogleda, bio je 229:256 g i u oglednoj grupi je bio veći za 27 g ili 11,79 posto (P<0,01). Jagnjad ogledne grupe je imala bolje iskorišćavanje suve materije, proteina i energije što ukazuje na opravdanost korišćenja preparata na bazi prirodnog zeolita kod jagnjadi u tovu
Efficient separation of Tc-99 from aqueous solution using pinecone activated carbon
Sorption of radioactive 99Tc-pertechnetate onto activated carbon prepared
from pinecones was investigated. The parameters of contact time and Tc-99
concentration were varied. It was established that the sorption half-life, t1/2,
was very short ~ 2.2 min, thus making this sorbent an excellent candidate
for immediate pollution remediation, which is very important in the case of
nuclear accidents. The kinetic data were found to follow closely the pseudosecond-
order (PSO) kinetic model. Boyd model established the sorption
dependence only on film diffusion. The partitioning/distribution coefficient,
Kd, attained was 2729 cm3 g-1. The equilibration time was 3 h at room
temperature (T=298 K)
Selenium nanoparticles render pandrug-resistant Acinetobacter baumannii susceptible to colistin
Colistin is used as a “last resort” drug in the treatmentof carbapenem-resistant Acinetobacter baumanniiinfections. Though not the most convenient option due tothe serious side effects, this antibiotic can be very efficientif administered properly (Garnacho-Montero and Timsit,2019). However, for several years now, we are witnessinga steady emergence of colistin-resistant (ColR) strains, withthe constant threat of a sudden burst worldwide (Nowak etal., 2017). Having in mind that these strains are usuallynon-susceptible to any of the existing treatments, i.e.pandrug-resistant (PDR), the development of newtherapeutic strategies is desperately needed.In the present study, we showed that colistinsusceptibility of ColR A. baumannii strains can be fullyrestored in the presence of very low amounts of seleniumnanoparticles (SeNPs). To demonstrate potent synergisticinteractions between colistin and SeNPs, we performedcheckerboard and time-kill analyses.The Seventh Congress ofPharmacy in North Macedonia with International participation 2022,october 5-9, Ohri
Antioxidant and lipid supplementation improve the development of photoreceptor outer segments in pluripotent stem cell-derived retinal organoids
The generation of retinal organoids from human pluripotent stem cells (hPSC) is now a well-established process that in part recapitulates retinal development. However, hPSC-derived photoreceptors that exhibit well-organized outer segment structures have yet to be observed. To facilitate improved inherited retinal disease modeling, we determined conditions that would support outer segment development in maturing hPSC-derived photoreceptors. We established that the use of antioxidants and BSA-bound fatty acids promotes the formation of membranous outer segment-like structures. Using new protocols for hPSC-derived retinal organoid culture, we demonstrated improved outer segment formation for both rod and cone photoreceptors, including organized stacked discs. Using these enhanced conditions to generate iPSC-derived retinal organoids from patients with X-linked retinitis pigmentosa, we established robust cellular phenotypes that could be ameliorated following adeno-associated viral vector-mediated gene augmentation. These findings should aid both disease modeling and the development of therapeutic approaches for the treatment of photoreceptor disorders
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