Search results for "Small"
showing 10 items of 2441 documents
Kinetics of the intestinal uptake of zinc acexamate in normal and zinc-depleted rats.
1990
Abstract The uptake of zinc as acexamic acid salt in the small intestine of the anaesthetized rat was shown to be a two-phase process in normal animals. The first phase is rapid mucosal binding which satisfies the Freundlich isotherm equation and which involves about 30 per cent of the initially perfused zinc. The second phase was characterized as an apparent absorption step which obeys Michaelis-Menten and first-order combined kinetics, with the following parameters: Vm = 6.51 mg h−1; Km = 2.96 mg; ka = 0.306 h−1. In largely non-saturated conditions, an apparent global rate constant of about 2.50 h−1 was calculated. No significant interference due to endogenous zinc excretion into the smal…
Intestinal absorption pathway of gamma-aminobutyric acid in rat small intestine.
1994
Intestinal absorption of gamma-aminobutyric acid (GABA), as a model compound for gamma-aminoacids, has not been extensively studied from the kinetic viewpoint. Since data from our laboratory suggested that some competition arises between intestinal absorption of beta-alanine and GABA and since our intent was to maintain the aqueous stagnant diffusion layer in order to approach absorption tests to in vivo physiological conditions, a rat jejunum in situ study was undertaken in order to gain an insight into the mechanism of GABA absorption. In the present paper, results from assays using isotonic perfusion solutions with starting GABA concentrations ranging from 1 to 50 mM are reported. They s…
Lung on a Chip Development from Off-Stoichiometry Thiol–Ene Polymer
2021
Institute of Solid-State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2. Finally, we would like to thank Biol. Kaspars Tars from Latvian Biomedical research and study center for giving us the opportunity to participate in this consortium and contribute to Latvian scientists’ effort in response to the COVID-19 pandemic.
Dual targeting of higher-order DNA structures by azacryptands induces DNA junction-mediated DNA damage in cancer cells
2021
Abstract DNA is intrinsically dynamic and folds transiently into alternative higher-order structures such as G-quadruplexes (G4s) and three-way DNA junctions (TWJs). G4s and TWJs can be stabilised by small molecules (ligands) that have high chemotherapeutic potential, either as standalone DNA damaging agents or combined in synthetic lethality strategies. While previous approaches have claimed to use ligands that specifically target either G4s or TWJs, we report here on a new approach in which ligands targeting both TWJs and G4s in vitro demonstrate cellular effects distinct from that of G4 ligands, and attributable to TWJ targeting. The DNA binding modes of these new, dual TWJ-/G4-ligands w…
Rheological modifiers based on supramolecular block copolymers: From weak associations to interconnected micelles
2019
Abstract The rheological spectra of poly(n-butyl acrylate) in the presence of a series of P(nBA-b-HEMA) rheology modifiers show a two-step relaxation process originating from the PnBA matrix and the self-assemblies. The HEMA segments are further grafted with strong, hydrogen bonding UPy groups, which both magnifies and slows down the relaxation of the assemblies. The extents of associations are enlightened by studying thermal transitions in DSC, morphological developments by SAXS, and description of rheological properties using a tube-based model. It is revealed that a weak association tendency, due to long hydrophobic blocks, leads to the formation of double-linear or star assemblies, whil…
Want to Impact Physical, Technical, and Tactical Performance during Basketball Small-Sided Games in Youth Athletes? Try Differential Learning Beforeh…
2020
This study aimed to analyze the acute effect of small-sided games, based on differential learning, on the physical, technical, and positioning performance of young basketball players. Eight basketball players under 13 (U13) participated in this study. A total of eight sessions involving half-court small-sided games (4 sets ×
The Small Size and Superficial Location Suggest That Laparoscopic Partial Nephrectomy Is the First Choice for the Treatment of Juxtaglomerular Cell T…
2021
BackgroundJuxtaglomerular cell tumor (JGCT) is a very rare disease, and surgical resection is the only possible way to cure this tumor. Open nephrectomy and partial nephrectomy have been reported to manage JGCTs with excellent results in the previous reviews. Laparoscopic surgery has been popularized in recent years, while critical issues associated with laparoscopic surgical management have been seldom reported. We summarized the JGCTs in our center to discover the optimal surgical management and its anatomic foundation.MethodsIn this retrospective study, we enrolled a total of 14 JGCT patients. All patients received surgeries and were followed up for up to 11 years. We mainly summarized t…
Measuring single small molecule binding via rupture forces of a split aptamer.
2011
The rupture force of a split (bipartite) aptamer that forms binding pockets for adenosine monophosphate (AMP) was measured by atomic force spectroscopy. Changes in the rupture force were observed in the presence of AMP, while this effect was absent when mutant aptamers or inosine were used. Thus, changes in the rupture force were a direct consequence of specific binding of AMP to the split aptamer. The split aptamer concept allowed the detection of nonlabeled AMP and enabled us to determine the dissociation constant on a single-molecule level.
The 18S ribosomal RNA m 6 A methyltransferase Mettl5 is required for normal walking behavior in Drosophila
2020
RNA modifications have recently emerged as an important layer of gene regulation. N6-methyladenosine (m6A) is the most prominent modification on eukaryotic messenger RNA and has also been found on noncoding RNA, including ribosomal and small nuclear RNA. Recently, several m6A methyltransferases were identified, uncovering the specificity of m6A deposition by structurally distinct enzymes. In order to discover additional m6A enzymes, we performed an RNAi screen to deplete annotated orthologs of human methyltransferase-like proteins (METTLs) in Drosophila cells and identified CG9666, the ortholog of human METTL5. We show that CG9666 is required for specific deposition of m6A on 18S ribosomal …
The intestinal microbiota modulates the anticancer immune effects of cyclophosphamide
2013
The Microbiota Makes for Good Therapy The gut microbiota has been implicated in the development of some cancers, such as colorectal cancer, but—given the important role our intestinal habitants play in metabolism—they may also modulate the efficacy of certain cancer therapeutics. Iida et al. (p. 967 ) evaluated the impact of the microbiota on the efficacy of an immunotherapy [CpG (the cytosine, guanosine, phosphodiester link) oligonucleotides] and oxaliplatin, a platinum compound used as a chemotherapeutic. Both therapies were reduced in efficacy in tumor-bearing mice that lacked microbiota, with the microbiota important for activating the innate immune response against the tumors. Viaud et…