61 research outputs found
Complex and real Hermite polynomials and related quantizations
It is known that the anti-Wick (or standard coherent state) quantization of
the complex plane produces both canonical commutation rule and quantum spectrum
of the harmonic oscillator (up to the addition of a constant). In the present
work, we show that these two issues are not necessarily coupled: there exists a
family of separable Hilbert spaces, including the usual Fock-Bargmann space,
and in each element in this family there exists an overcomplete set of
unit-norm states resolving the unity. With the exception of the Fock-Bargmann
case, they all produce non-canonical commutation relation whereas the quantum
spectrum of the harmonic oscillator remains the same up to the addition of a
constant. The statistical aspects of these non-equivalent coherent states
quantizations are investigated. We also explore the localization aspects in the
real line yielded by similar quantizations based on real Hermite polynomials.Comment: 15 pages, 6 figure
Comments on the Properties of Mittag-Leffler Function
The properties of Mittag-Leffler function is reviewed within the framework of
an umbral formalism. We take advantage from the formal equivalence with the
exponential function to define the relevant semigroup properties. We analyse
the relevant role in the solution of Schr\"odinger type and heat-type
fractional partial differential equations and explore the problem of
operatorial ordering finding appropriate rules when non-commuting operators are
involved. We discuss the coherent states associated with the fractional
Sch\"odinger equation, analyze the relevant Poisson type probability amplitude
and compare with analogous results already obtained in the literature.Comment: 16 pages, 9 figure
Polysaccharide BAP1 of Bifidobacterium adolescentis CCDM 368 is a biologically active molecule with immunomodulatory properties
Bifidobacteria are among the most common bacteria used for their probiotic properties and their impact on the maturation and function of the immune system has been well-described. Recently, scientific interest is shifting from live bacteria to defined bacteria-derived biologically active molecules. Their greatest advantage over probiotics is the defined structure and the effect independent of the viability status of the bacteria. Here, we aim to characterize Bifidobacterium adolescentis CCDM 368 surface antigens that include polysaccharides (PSs), lip-oteichoic acids (LTAs), and peptidoglycan (PG). Among them, Bad368.1 PS was observed to modulate OVA-induced cytokine production in cells isolated from OVA-sensitized mice by increasing the production of Th1-related IFN-gamma and inhibition of Th2-related IL-5 and IL-13 cytokines (in vitro). Moreover, Bad368.1 PS (BAP1) is efficiently engulfed and transferred between epithelial and dendritic cells. Therefore, we propose that the Bad368.1 PS (BAP1) can be used for the modulation of allergic diseases in humans. Structural studies revealed that Bad368.1 PS has an average molecular mass of approximately 9,99 x 106 Da and it consists of glucose, galactose, and rhamnose residues that are creating the following repeating unit: [-> 2)-beta-D-Glcp-(1 -> 3)-beta-L-Rhap-(1 -> 4)-beta-D-Glcp-(1 -> 3)-alpha-L-Rhap-(1 -> 4)-beta-D-Glcp-(1 -> 3)-alpha-D-Galp-(1 -> ]
Prenyl Ammonium Salts – New Carriers for Gene Delivery: A B16-F10 Mouse Melanoma Model
Purpose
Prenyl ammonium iodides (Amino-Prenols, APs), semi-synthetic polyprenol derivatives were studied as prospective novel gene transfer agents.
Methods
AP-7, -8, -11 and -15 (aminoprenols composed of 7, 8, 11 or 15 isoprene units, respectively)were examined for their capacity to form complexes with pDNA, for cytotoxicity and ability to transfect genes to cells.
Results
All the carriers were able to complex DNA. The highest, comparable to commercial reagents, transfection efficiency was observed for AP-15. Simultaneously, AP-15 exhibited the lowest negative impact on cell viability and proliferation—considerably lower than that of commercial agents. AP-15/DOPE complexes were also efficient to introduce pDNA to cells, without much effect on cell viability. Transfection with AP-15/DOPE complexes influenced the expression of a very few among 44 tested genes involved in cellular lipid metabolism. Furthermore, complexes containing AP-15 and therapeutic plasmid, encoding the TIMP metallopeptidase inhibitor 2 (TIMP2), introduced the TIMP2 gene with high efficiency to B16-F10 melanoma cells but not to B16-F10 melanoma tumors in C57BL/6 mice, as confirmed by
TIMP2 protein level determination.
Conclusion
Obtained results indicate that APs have a potential as non-viral vectors for cell transfection
Combining low-dose CT-based radiomics and metabolomics for early lung cancer screening support
Due to its predominantly asymptomatic or mildly symptomatic progression, lung
cancer is often diagnosed in advanced stages, resulting in poorer survival
rates for patients. As with other cancers, early detection significantly
improves the chances of successful treatment. Early diagnosis can be
facilitated through screening programs designed to detect lung tissue tumors
when they are still small, typically around 3mm in size. However, the analysis
of extensive screening program data is hampered by limited access to medical
experts. In this study, we developed a procedure for identifying potential
malignant neoplastic lesions within lung parenchyma. The system leverages
machine learning (ML) techniques applied to two types of measurements: low-dose
Computed Tomography-based radiomics and metabolomics. Using data from two
Polish screening programs, two ML algorithms were tested, along with various
integration methods, to create a final model that combines both modalities to
support lung cancer screening
Reduction of Neuropathic and Inflammatory Pain through Inhibition of the Tetrahydrobiopterin Pathway
Human genetic studies have revealed an association between GTP cyclohydrolase 1 polymorphisms, which decrease tetrahydrobiopterin (BH4) levels, and reduced pain in patients. We now show that excessive BH4 is produced in mice by both axotom- ized sensory neurons and macrophages infiltrating damaged nerves and inflamed tissue. Constitutive BH4 overproduction in sensory neurons increases pain sensitivity, whereas blocking BH4 production only in these cells reduces nerve injury-induced hy- persensitivity without affecting nociceptive pain. To minimize risk of side effects, we targeted sepiapterin reductase (SPR), whose blockade allows minimal BH4 production through the BH4 salvage pathways. Using a structure-based design, we developed a potent SPR inhibitor and show that it reduces pain hypersensitivity effectively with a concomitant decrease in BH4 levels in target tissues, acting both on sensory neurons and macrophages, with no development of tolerance or adverse effects. Finally, we demonstrate that sepiapterin accumulation is a sensitive biomarker for SPR inhibition in vivo
Rapid miRNA Imaging in Cells Using Fluorogenic Templated Staudinger Reaction Between PNA-Based Probes
Reactions templated by a specific nucleic acid sequence have emerged as an attractive strategy for nucleic acid sensing. The Staudinger reaction using an azide-quenched fluorophore and a phosphine is particularly well suited by virtue of its bioorthogonality and biocompatibility. The reaction is promoted by a complementary nucleic acid that aligns the phosphine with the azide-quenched fluorophore. Cellular RNAs can catalyze the Staudinger reaction and signal amplification can be achieved through multiple turnover of the template. Peptide nucleic acids (PNA) provide a convenient platform for the preparation of specific probes as they combine desirable hybridization properties, robust synthesis, ease of fluorophore conjugation, and high biochemical stability. Herein, we describe protocols for fast fluorescent detection of miRNAs in human cells with PNA-based probes via reductive unquenching of bis-azidorhodamine by trialkylphosphine
Reactions Templated by Nucleic Acids: More Ways to Translate Oligonucleotide-Based Instructions into Emerging Function
The programmability of oligonucleotide recognition offers an attractive platform to direct the assembly of reactive partners that can engage in chemical reactions. Recently, significant progress has been made in both the breadth of chemical transformations and in the functional output of the reaction. Herein we summarize these recent progresses and illustrate their applications to translate oligonucleotide instructions into functional materials and novel architectures (conductive polymers, nanopatterns, novel oligonucleotide junctions); into fluorescent or bioactive molecule using cellular RNA; to interrogate secondary structures or oligonucelic acids; or a synthetic oligomer
Emergence de fonctions des auto-assemblages programmés par des acides nucléiques
Mon travail de thèse avait pour objet l application d assemblages supramoléculaires pour traduire l information portée par lesacides nucléiques en fonctions artificielles. Les acides peptidiques (Peptide Nucleic Acid, PNA) possédant des propriétés proches des acides ribonucléiques ont été choisis comme support pour la construction de sondes capables de s hybrider à l ADN ou à l ARN. Cette hybridation peut être utilisée pour provoquer des réactions chimiques entre deux sondes ou pour adapter la structure d un ligand à celle du site actif d une cible biologique. Ces systèmes ont été optimisés pour opérer dans des conditions physiologiques et utilisés avec succès pour visualiser des ARN cellulaires, libérer de façon programmable de petites molécules d intérêt thérapeutique et pour étudier les interactions multimériques ligand-récepteur.This PhD project aimed for application of supramolecular self-assemblies for translating instructions from natural information carriers, nucleic acids, into artificial functions. The peptide nucleic acid (PNA), a functional analogue of natural nucleic acid, was chosen as a scaffold for construction of profunctional probes. Upon hybridization to the template, these conjugates can be triggered to undergo programmed chemical reaction or adapt required topology for binding to biological target. Such systems has been tuned to operate in physiological conditions and employed successfully for imaging of cellular RNAs, sequence specific release of small molecules as well as for studying multivalent ligand-receptor interactions.STRASBOURG-Sc. et Techniques (674822102) / SudocSudocFranceF
Nucleic Acid Templated Uncaging of Fluorophores Using Ru-Catalyzed Photoreduction with Visible Light
Hybridization-based reactions have attracted significant attention. The nucleic acid templated photocatalyzed azide reduction using catalytic amounts of a [Ru(bpy)2phen]2+ conjugate is reported. The reaction could be performed with as little as 2% of the Ru nucleic acid probe and was shown to productively unquench 7-azido-coumarin as well as uncage a small molecule
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