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1.
Nat Med ; 30(6): 1771-1783, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38890531

RESUMO

Minimally invasive biomarkers are urgently needed to detect molecular pathology in frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Here, we show that plasma extracellular vesicles (EVs) contain quantifiable amounts of TDP-43 and full-length tau, which allow the quantification of 3-repeat (3R) and 4-repeat (4R) tau isoforms. Plasma EV TDP-43 levels and EV 3R/4R tau ratios were determined in a cohort of 704 patients, including 37 genetically and 31 neuropathologically proven cases. Diagnostic groups comprised patients with TDP-43 proteinopathy ALS, 4R tauopathy progressive supranuclear palsy, behavior variant FTD (bvFTD) as a group with either tau or TDP-43 pathology, and healthy controls. EV tau ratios were low in progressive supranuclear palsy and high in bvFTD with tau pathology. EV TDP-43 levels were high in ALS and in bvFTD with TDP-43 pathology. Both markers discriminated between the diagnostic groups with area under the curve values >0.9, and between TDP-43 and tau pathology in bvFTD. Both markers strongly correlated with neurodegeneration, and clinical and neuropsychological markers of disease severity. Findings were replicated in an independent validation cohort of 292 patients including 34 genetically confirmed cases. Taken together, the combination of EV TDP-43 levels and EV 3R/4R tau ratios may aid the molecular diagnosis of FTD, FTD spectrum disorders and ALS, providing a potential biomarker to monitor disease progression and target engagement in clinical trials.


Assuntos
Esclerose Lateral Amiotrófica , Biomarcadores , Proteínas de Ligação a DNA , Vesículas Extracelulares , Demência Frontotemporal , Proteínas tau , Humanos , Esclerose Lateral Amiotrófica/sangue , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/genética , Proteínas tau/sangue , Proteínas tau/metabolismo , Vesículas Extracelulares/metabolismo , Demência Frontotemporal/sangue , Demência Frontotemporal/diagnóstico , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Biomarcadores/sangue , Proteínas de Ligação a DNA/sangue , Proteínas de Ligação a DNA/genética , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Paralisia Supranuclear Progressiva/sangue , Paralisia Supranuclear Progressiva/diagnóstico , Isoformas de Proteínas/sangue
2.
Opt Express ; 32(8): 14847-14859, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859420

RESUMO

This article presents an experimental demonstration of a spectroscopic method based on the dispersion of the scattering spectrum from laser-illuminated liquid water collected through a rubidium atomic vapor prism cell. Resonant absorption at 780 nm suppresses Mie/Rayleigh scattering and the steep gradients in refractive index near the 780 nm absorption lines separate Brillouin scattering from Raman scattering in liquid water. The opposing spatial displacements of the Stokes and Anti-Stokes shifted Brillouin peaks yield a measurement of their spectral shifts and thus the temperature or salinity of the water. Performance of the prism cell was mapped with a frequency tunable laser for frequency offsets from the center of the rubidium absorption feature of between -15 GHz and 15 GHz and at rubidium cell temperatures between 148 °C and 177 °C. The experimental results are compared with a numerical model and show good agreement with the scattering peak displacements within experimental uncertainties of probe frequency and cell temperature. In the present configuration, the minimum detectable frequency shift is estimated to be 15.5 MHz. Experiments were conducted in water demonstrating the utility of this method for the measurement of water temperature. Liquid water LiDAR was suggested as one of the possible applications for this method and several ways to improve the experimental setup and cell temperature stability were identified.

3.
Brain ; 147(7): 2428-2439, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38842726

RESUMO

Four-repeat (4R) tauopathies are neurodegenerative diseases characterized by cerebral accumulation of 4R tau pathology. The most prominent 4R tauopathies are progressive supranuclear palsy (PSP) and corticobasal degeneration characterized by subcortical tau accumulation and cortical neuronal dysfunction, as shown by PET-assessed hypoperfusion and glucose hypometabolism. Yet, there is a spatial mismatch between subcortical tau deposition patterns and cortical neuronal dysfunction, and it is unclear how these two pathological brain changes are interrelated. Here, we hypothesized that subcortical tau pathology induces remote neuronal dysfunction in functionally connected cortical regions to test a pathophysiological model that mechanistically links subcortical tau accumulation to cortical neuronal dysfunction in 4R tauopathies. We included 51 Aß-negative patients with clinically diagnosed PSP variants (n = 26) or corticobasal syndrome (n = 25) who underwent structural MRI and 18F-PI-2620 tau-PET. 18F-PI-2620 tau-PET was recorded using a dynamic one-stop-shop acquisition protocol to determine an early 0.5-2.5 min post tracer-injection perfusion window for assessing cortical neuronal dysfunction, as well as a 20-40 min post tracer-injection window to determine 4R-tau load. Perfusion-PET (i.e. early window) was assessed in 200 cortical regions, and tau-PET was assessed in 32 subcortical regions of established functional brain atlases. We determined tau epicentres as subcortical regions with the highest 18F-PI-2620 tau-PET signal and assessed the connectivity of tau epicentres to cortical regions of interest using a resting-state functional MRI-based functional connectivity template derived from 69 healthy elderly controls from the ADNI cohort. Using linear regression, we assessed whether: (i) higher subcortical tau-PET was associated with reduced cortical perfusion; and (ii) cortical perfusion reductions were observed preferentially in regions closely connected to subcortical tau epicentres. As hypothesized, higher subcortical tau-PET was associated with overall lower cortical perfusion, which remained consistent when controlling for cortical tau-PET. Using group-average and subject-level PET data, we found that the seed-based connectivity pattern of subcortical tau epicentres aligned with cortical perfusion patterns, where cortical regions that were more closely connected to the tau epicentre showed lower perfusion. Together, subcortical tau-accumulation is associated with remote perfusion reductions indicative of neuronal dysfunction in functionally connected cortical regions in 4R-tauopathies. This suggests that subcortical tau pathology may induce cortical dysfunction, which may contribute to clinical disease manifestation and clinical heterogeneity.


Assuntos
Córtex Cerebral , Tomografia por Emissão de Pósitrons , Paralisia Supranuclear Progressiva , Tauopatias , Proteínas tau , Humanos , Masculino , Feminino , Tomografia por Emissão de Pósitrons/métodos , Idoso , Tauopatias/diagnóstico por imagem , Tauopatias/metabolismo , Tauopatias/patologia , Proteínas tau/metabolismo , Pessoa de Meia-Idade , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/metabolismo , Paralisia Supranuclear Progressiva/patologia , Paralisia Supranuclear Progressiva/fisiopatologia , Imageamento por Ressonância Magnética/métodos
4.
Chem Commun (Camb) ; 60(45): 5840-5843, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38751319

RESUMO

Dual-gasochromic supraparticles that undergo rapid eye-readable and gas-specific colour changes upon reaction with hydrogen or ammonia are reported. This functionality is achieved by tailoring the solid-liquid-gas interface within the mesoporous framework of supraparticles via spray-drying.

5.
Life Sci Space Res (Amst) ; 41: 80-85, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38670656

RESUMO

The disuse of skeletal limb muscles occurs in a variety of conditions, yet our comprehension of the molecular mechanisms involved in adaptation to disuse remains incomplete. We studied the mechanical characteristics of actin-myosin interaction using an in vitro motility assay and isoform composition of myosin heavy and light chains by dint of SDS-PAGE in soleus muscle of both control and hindlimb-unloaded rats. 14 days of hindlimb unloading led to the increased maximum sliding velocity of actin, reconstituted, and native thin filaments over rat soleus muscle myosin by 24 %, 19 %, and 20 %, respectively. The calcium sensitivity of the "pCa-velocity" relationship decreased. There was a 26 % increase in fast myosin heavy chain IIa (MHC IIa), a 22 % increase in fast myosin light chain 2 (MLC 2f), and a 13 % increase in fast MLC 1f content. The content of MLC 1s/v, typical for slow skeletal muscles and cardiac ventricles did not change. At the same time, MLC 1s, typical only for slow skeletal muscles, disappeared. The maximum velocity of soleus muscle native thin filaments was 24 % higher compared to control ones sliding over the same rabbit myosin. Therefore, both myosin and native thin filament kinetics could influence the mechanical characteristics of the soleus muscle. Additionally, the MLC 1s and MLC 1s/v ratio may contribute to the mechanical characteristics of slow skeletal muscle, along with MHC, MLC 2, and MLC 1 slow/fast isoforms ratio.


Assuntos
Elevação dos Membros Posteriores , Músculo Esquelético , Ratos Wistar , Animais , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Ratos , Masculino , Cadeias Pesadas de Miosina/metabolismo , Cadeias Leves de Miosina/metabolismo , Coelhos , Miosinas/metabolismo , Cálcio/metabolismo , Citoesqueleto de Actina/metabolismo , Isoformas de Proteínas
6.
J Am Chem Soc ; 146(10): 7105-7115, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38417151

RESUMO

The binding of nucleotides is crucial for signal transduction as it induces conformational protein changes, leading to downstream cellular responses. Synthetic receptors that bind nucleotides and transduce the binding event into global conformational rearrangements are highly challenging to design, especially those that operate in an aqueous solution. Much work is focused on evaluating functionalized dyes to detect nucleotides, whereas coupling of a nucleotide-induced conformational switching to a sensing event has not been reported to date. We disclose synthetic receptors that undergo a global conformational rearrangement upon nucleotide binding. Integrating naphthalimide and the pyridinium ion into the structure enables stabilization of the folded conformation and efficient fluorescence quenching. The binding of a nucleotide rearranges the receptor conformation and alters the strong fluorescence enhancement. The methylpyridinium-containing receptor demonstrated high sensing selectivity for adenosine 5'-triphosphate (ATP) and a record 160-fold fluorescence enhancement. It can detect fluctuations of ATP in HeLa cells and possesses low cytotoxicity. The developed systems present an attractive approach for designing ATP-responsive artificial molecular switches that operate in water and integrate a strong fluorescence response.


Assuntos
Trifosfato de Adenosina , Receptores Artificiais , Humanos , Trifosfato de Adenosina/química , Fluorescência , Células HeLa , Nucleotídeos/metabolismo , Tomografia por Emissão de Pósitrons , Espectrometria de Fluorescência , Conformação Proteica , Corantes Fluorescentes/química , Difosfato de Adenosina/metabolismo
7.
Opt Lett ; 49(3): 426-429, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300024

RESUMO

This Letter describes, to the best of our knowledge, a new approach to flow tagging, nitric oxide (NO) Ionization Induced Flow Tagging and Imaging (NiiFTI), and presents the first experimental demonstration for single-shot velocimetry in a near Mach 6 hypersonic flow at 250 kHz. The mean velocity of 860 m/s was measured with a single-shot standard deviation of as low as 3.4 m/s and mean velocity uncertainty of 5.5 m/s. NiiFTI is characterized by a long fluorescence lifetime of nitrogen with 1e decay of approximately 50 µs measured in air. The method relies on a single nanosecond laser combined with a high-speed camera, creating an opportunity for the utilization of a typical nitric oxide (NO) laser-induced fluorescence (LIF) experimental setup with minor modifications as well as pulse-burst lasers (PBLs) for ultrahigh repetition rates.

8.
Pflugers Arch ; 476(5): 735-753, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38424322

RESUMO

Genetic variants of gene SCN5A encoding the alpha-subunit of cardiac voltage-gated sodium channel Nav1.5 are associated with various diseases, including long QT syndrome (LQT3), Brugada syndrome (BrS1), and progressive cardiac conduction disease (PCCD). In the last decades, the great progress in understanding molecular and biophysical mechanisms of these diseases has been achieved. The LQT3 syndrome is associated with gain-of-function of sodium channels Nav1.5 due to impaired inactivation, enhanced activation, accelerated recovery from inactivation or the late current appearance. In contrast, BrS1 and PCCD are associated with the Nav1.5 loss-of-function, which in electrophysiological experiments can be manifested as reduced current density, enhanced fast or slow inactivation, impaired activation, or decelerated recovery from inactivation. Genetic variants associated with congenital arrhythmias can also disturb interactions of the Nav1.5 channel with different proteins or drugs and cause unexpected reactions to drug administration. Furthermore, mutations can affect post-translational modifications of the channels and their sensitivity to pH and temperature. Here we briefly review the current knowledge on biophysical mechanisms of LQT3, BrS1 and PCCD. We focus on limitations of studies that use heterologous expression systems and induced pluripotent stem cells (iPSC) derived cardiac myocytes and summarize our understanding of genotype-phenotype relations of SCN5A mutations.


Assuntos
Canalopatias , Canal de Sódio Disparado por Voltagem NAV1.5 , Humanos , Animais , Canalopatias/genética , Canalopatias/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Miocárdio/metabolismo , Síndrome de Brugada/genética , Síndrome de Brugada/metabolismo , Síndrome do QT Longo/genética , Síndrome do QT Longo/metabolismo , Síndrome do QT Longo/fisiopatologia
9.
Adv Protein Chem Struct Biol ; 138: 67-99, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38220433

RESUMO

Mammalian translation elongation factors eEF1A1 and eEF1A2 are 92% homologous isoforms whose mutually exclusive tissue-specific expression is regulated during development. The isoforms have similar translation functionality, but show differences in spatial organization and participation in various processes, such as oncogenesis and virus reproduction. The differences may be due to their ability to interact with isoform-specific partner proteins. We used the identified sets of eEF1A1 or eEF1A2 partner proteins to identify cell complexes and/or processes specific to one particular isoform. As a result, we found isoform-specific interactions reflecting the involvement of different eEF1A isoforms in different cellular processes, including actin-related, chromatin-remodeling, ribonuclease H2, adenylyl cyclase, and Cul3-RING ubiquitin ligase complexes as well as initiation of mitochondrial transcription. An essential by-product of our analysis is the elucidation of a number of cellular processes beyond protein biosynthesis, where both isoforms appear to participate such as large ribosomal subunit biogenesis, mRNA splicing, DNA mismatch repair, 26S proteasome activity, P-body and exosomes formation, protein targeting to the membrane. This information suggests that a relatively high content of eEF1A in the cell may be necessary not only to maintain efficient translation, but also to ensure its participation in various cellular processes, where some roles of eEF1A have not yet been described. We believe that the data presented here will be useful for deciphering new auxiliary functions of eEF1A and its isoforms, and provide a new look at the known non-canonical functions of this main component of the human translation-elongation machinery.


Assuntos
Biossíntese de Proteínas , Proteômica , Animais , Humanos , Mamíferos , Isoformas de Proteínas/genética
10.
Arch Biochem Biophys ; 751: 109844, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043889

RESUMO

The current study aimed to investigate the hypothesis that purinergic receptors P2Y1 and P2Y2 play a regulatory role in gene expression in unloaded muscle. ATP is released from cells through pannexin channels, and it interacts with P2Y1 and P2Y2 receptors, leading to the activation of markers of protein catabolism and a reduction in protein synthesis. To test this hypothesis thirty-two rats were randomly divided into four groups (8 per group): a non-treated control group (C), a group subjected to three days of hindlimb unloading with a placebo (HS), a group subjected to three days of hindlimb unloading treated with a P2Y1 receptor inhibitor, MRS2179 (HSM), and a group subjected to three days of hindlimb unloading treated with a P2Y2 receptor inhibitor, AR-C 118925XX (HSA). This study revealed several key findings following three days of soleus muscle unloading: 1: Inhibition of P2Y1 or P2Y2 receptors prevented the accumulation of ATP, the increase in IP3 receptor content, and the decrease in the phosphorylation of GSK-3beta. This inhibition also mitigated the reduction in the rate of protein synthesis. However, it had no significant effect on the markers of mTORC1-dependent signaling. 2: Blocking P2Y1 receptors prevented the unloading-induced upregulation of phosphorylated p38MAPK and partially reduced the increase in MuRF1mRNA expression. 3: Blocking P2Y2 receptors prevented muscle atrophy during unloading, partially maintained the levels of phosphorylated ERK1/2, reduced the increase in mRNA expression of MAFbx, ubiquitin, and IL-6 receptor, prevented the decrease in phosphorylated AMPK, and attenuated the increase in phosphorylated p70S6K. Taken together, these results suggest that the prevention of muscle atrophy during unloading, as achieved by the P2Y2 receptor inhibitor, is likely mediated through a reduction in catabolic processes and maintenance of energy homeostasis. In contrast, the P2Y1 receptor appears to play a relatively minor role in muscle atrophy during unloading.


Assuntos
Músculo Esquelético , Transdução de Sinais , Animais , Ratos , Trifosfato de Adenosina/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Receptores Purinérgicos P2Y1/metabolismo , Receptores Purinérgicos P2Y2/genética , Receptores Purinérgicos P2Y2/metabolismo
11.
PLoS One ; 18(12): e0295974, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38100498

RESUMO

BACKGROUND: TRPM4 is a calcium-activated channel that selectively permeates monovalent cations. Genetic variants of the channel in cardiomyocytes are associated with various heart disorders, such as progressive familial heart block and Brugada syndrome. About97% of all known TRPM4 missense variants are classified as variants of unknown clinical significance (VUSs). The very large number of VUSs is a serious problem in diagnostics and treatment of inherited heart diseases. METHODS AND RESULTS: We collected 233 benign or pathogenic missense variants in the superfamily of TRP channels from databases ClinVar, Humsavar and Ensembl Variation to compare performance of 22 algorithms that predict damaging variants. We found that ClinPred is the best-performing tool for TRP channels. We also used the paralogue annotation method to identify disease variants across the TRP family. In the set of 565 VUSs of hTRPM4, ClinPred predicted pathogenicity of 299 variants. Among these, 12 variants are also categorized as LP/P variants in at least one paralogue of hTRPM4. We further used the cryo-EM structure of hTRPM4 to find scores of contact pairs between parental (wild type) residues of VUSs for which ClinPred predicts a high probability of pathogenicity of variants for both contact partners. We propose that 68 respective missense VUSs are also likely pathogenic variants. CONCLUSIONS: ClinPred outperformed other in-silico tools in predicting damaging variants of TRP channels. ClinPred, the paralogue annotation method, and analysis of residue contacts the hTRPM4 cryo-EM structure collectively suggest pathogenicity of 80 TRPM4 VUSs.


Assuntos
Síndrome de Brugada , Cardiopatias , Canais de Cátion TRPM , Humanos , Relevância Clínica , Mutação de Sentido Incorreto , Síndrome de Brugada/genética , Algoritmos , Canais de Cátion TRPM/genética
12.
Opt Express ; 31(22): 37074-37081, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-38017844

RESUMO

The concept of invisible optical states in dielectric particles is developed. Two cases for excitation of invisible states are discussed. The first one is the excitation in the microparticles with fixed shapes (e.g. spheres) by variation of the properties of incident radiation. The second one is the search for a complex shape of a particle in which invisible states are excited for fixed properties of the incident radiation (e.g. a plane wave). Based on the proposed numerical assessment of the invisibility of the scattered field, a method for finding invisible particles by varying its shape has been developed. A method for calculating the scattered field is generalized in the framework of the theory of surface perturbation for the case of an arbitrary initial shape of the particle.

13.
Am J Physiol Endocrinol Metab ; 325(6): E734-E743, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37938180

RESUMO

The soleus muscle in humans is responsible for maintaining an upright posture and participating in walking and running. Under muscle disuse, it undergoes molecular signaling changes that result in altered force and work capacity. The triggering mechanisms and pathways of these changes are not yet fully understood. In this article, we aimed to detect the molecular pathways that are involved in the unloading-induced alterations in the human soleus muscle under 6-days of dry immersion. A 6-day dry immersion led to the downregulation of mitochondrial biogenesis and dynamics markers, upregulation of calcium-dependent CaMK II phosphorylation, enhanced PGC1α promoter region methylation, and altered muscle micro-RNA expression, without affecting p-AMPK content or fiber-type transformation.NEW & NOTEWORTHY Dry immersion dysregulates mitochondrial genes expression, affects mi-RNA expression and PGC1 promoter methylation.


Assuntos
Imersão , Músculo Esquelético , Humanos , Regulação para Baixo , Músculo Esquelético/metabolismo , DNA Mitocondrial/metabolismo , Mitocôndrias/metabolismo , RNA/metabolismo
14.
J Gen Physiol ; 155(11)2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37728574

RESUMO

Opposite effects of 1,4-dihydropyridine (DHP) agonists and antagonists on the L-type calcium channels are a challenging problem. Cryo-EM structures visualized DHPs between the pore-lining helices S6III and S6IV in agreement with published mutational data. However, the channel conformations in the presence of DHP agonists and antagonists are virtually the same, and the mechanisms of the ligands' action remain unclear. We docked the DHP agonist S-Bay k 8644 and antagonist R-Bay k 8644 in Cav1.1 channel models with or without π-bulges in helices S6III and S6IV. Cryo-EM structures of the DHP-bound Cav1.1 channel show a π-bulge in helix S6III but not in S6IV. The antagonist's hydrophobic group fits into the hydrophobic pocket formed by residues in S6IV. The agonists' polar NO2 group is too small to fill up the pocket. A water molecule could sterically fit into the void space, but its contacts with isoleucine in helix S6IV (motif INLF) would be unfavorable. In a model with π-bulged S6IV, this isoleucine turns away from the DHP molecule and its position is occupied by the asparagine from the same motif INLF. The asparagine provides favorable contacts for the water molecule at the agonist's NO2 group but unfavorable contacts for the antagonist's methoxy group. In our models, the DHP antagonist stabilizes entirely α-helical S6IV. In contrast, the DHP agonist stabilizes π-bulged helix S6IV whose C-terminal part turned and rearranged the activation-gate region. This would stabilize the open channel. Thus, agonists, but not antagonists, would promote channel opening by stabilizing π-bulged helix S6IV.


Assuntos
Cálcio , Di-Hidropiridinas , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil) , Asparagina , Microscopia Crioeletrônica , Isoleucina , Dióxido de Nitrogênio , Di-Hidropiridinas/farmacologia , Canais de Sódio
15.
Photochem Photobiol Sci ; 22(11): 2651-2673, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37733213

RESUMO

This study focuses on the molecular design and synthesis of salt spiropyrans with near-IR fluorescence. The structure of the obtained compounds was confirmed by NMR, IR and mass spectroscopy. In the course of studying the spectral and photoluminescent characteristics, it was possible to reveal the effect of some substituents in various positions on the properties of spiropyran dyes. Due to the structural similarity of one of the isomers to cyanine dyes, the obtained compounds are of interest as potential fluorescent probes for bioimagimg, in particular, for DNA studies. To reveal their ability of binding to DNA molecules molecular docking was carried out. Toxic effects of compounds demonstrating NIR fluorescence were studied on biofilms, as well as using bacterial lux-biosensors.


Assuntos
Benzopiranos , Corantes Fluorescentes , Simulação de Acoplamento Molecular , Benzopiranos/química , Corantes Fluorescentes/química , DNA
16.
Biomolecules ; 13(9)2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37759754

RESUMO

Skeletal muscle abnormalities and atrophy during unloading are accompanied by the accumulation of excess calcium in the sarcoplasm. We hypothesized that calcium accumulation may occur, among other mechanisms, due to the inhibition of sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) activity. Consequently, the use of the SERCA activator will reduce the level of calcium in the sarcoplasm and prevent the negative consequences of muscle unloading. Wistar rats were randomly assigned into one of three groups (eight rats per group): control rats with placebo (C), 7 days of unloading/hindlimb suspension with placebo (7HS), and 7 days of unloading treated with SERCA activator CDN1163 (7HSC). After seven days of unloading the soleus muscle, the 7HS group displayed increased fatigue in the ex vivo test, a significant increase in the level of calcium-dependent CaMK II phosphorylation and the level of tropomyosin oxidation, as well as a decrease in the content of mitochondrial DNA and protein, slow-type myosin mRNA, and the percentage of slow-type muscle fibers. All of these changes were prevented in the 7HSC group. Moreover, treatment with CDN1163 blocked a decrease in the phosphorylation of p70S6k, an increase in eEF2 phosphorylation, and an increase in MuRF-1 mRNA expression. Nevertheless, there were no differences in the degree of fast and slow muscle fiber atrophy between the 7HS and 7HSC groups. Conclusion: SERCA activation during 7 days of unloading prevented an increase in soleus fatigue, the decrease of slow-type myosin, mitochondrial markers, and markers of calcium homeostasis but had no effect on muscle atrophy.


Assuntos
Cálcio , Músculo Esquelético , Ratos , Animais , Ratos Wistar , Atrofia Muscular/tratamento farmacológico , Retículo Endoplasmático
17.
Microorganisms ; 11(8)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37630503

RESUMO

This paper investigates the antagonistic and plant growth promotion activity of the new indigenous bacteria antagonist strains P. chlororaphis BZR 245-F and Pseudomonas sp. BZR 523-2. It was found that on the 10th day of cultivation, BZR 245-F and BZR 523-2 exhibit an antagonistic activity against F. graminearum at the level of 59.6% and 15.1% and against F. oxysporum var. orthoceras at the level of 50.2% and 8.9%, respectively. Furthermore, the BZR 523-2 strain stimulated the growth of winter wheat seedlings more actively than the BZR 245-F strain. When processing seeds of winter wheat, Pseudomonas sp. BZR 523-2 indicators were higher than in the control: plant height increased by 10.3%, and root length increased by 18.6%. The complex characteristic properties of the metabolite were studied by bioautography and HPLC-MS. Bioautography proved the antifungal activity of phenazine nature compounds synthesized by the new bacterial strains. We qualitatively and quantitatively analyzed them by HPLC-MS analysis of the strain sample metabolites. In the BZR 245-F sample, we found more phenazine compounds of various types. Their total phenazine concentration in the BZR 245-F was more than five times greater than in the BZR 523-2. We defined crucial differences in the quantitative content of the other metabolites. Despite the difference between new indigenous bacteria antagonist strains, they can be used as producers of effective biopesticides for sustainable agriculture management.

18.
Front Immunol ; 14: 1228461, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600800

RESUMO

To protect young individuals against SARS-CoV-2 infection, we conducted an open-label, prospective, non-randomised dose-escalation Phase 1/2 clinical trial to evaluate the immunogenicity and safety of the prime-boost "Sputnik V" vaccine administered at 1/10 and 1/5 doses to adolescents aged 12-17 years. The study began with the vaccination of the older cohort (15-to-17-year-old participants) with the lower (1/10) dose of vaccine and then expanded to the whole group (12-to-17-year-old participants). Next, 1/5 dose was used according to the same scheme. Both doses were well tolerated by all age groups. No serious or severe adverse events were detected. Most of the solicited adverse reactions were mild. No significant differences in total frequencies of adverse events were registered between low and high doses in age-pooled groups (69.6% versus 66.7%). In contrast, the 1/5 dose induced significantly higher humoral and T cell-mediated immune responses than the 1/10 dose. The 1/5 vaccine dose elicited higher antigen-binding (both S and RBD-specific) as well as virus-neutralising antibody titres at the maximum of response (day 42), also resulting in a statistically significant difference at a distanced timepoint (day 180) compared to the 1/10 vaccine dose. Higher dose resulted in increased cross-neutralization of Delta and Omicron variants. Clinical Trial Registration: ClinicalTrials.gov, NCT04954092, LP-007632.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adolescente , Criança , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Estudos Prospectivos , SARS-CoV-2
20.
Phys Rev E ; 108(1-1): 014302, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37583140

RESUMO

We have found that phase transitions occurring between three traffic phases [free flow (F), synchronized flow (S), and wide moving jam (J)] determine the spatiotemporal dynamics of traffic consisting of 100% automated-driving vehicles moving on a two-lane road with an on-ramp bottleneck. This means that three-phase traffic theory is a common framework for the description of traffic states independent of whether human-driving or automated-driving vehicles move in vehicular traffic. To prove this, we have studied automated-driving vehicular traffic with the use of classical Helly's model [Proceedings of the Symposium on Theory of Traffic Flow (Elsevier, Amsterdam, 1959), pp. 207-238] widely applied for automated vehicle motion. Although dynamic rules of the motion of automated-driving vehicles in a road lane are qualitatively different from those of human-driving vehicles, we have revealed that traffic breakdown (F→S transition) at the bottleneck exhibits the nucleation nature, which was observed in empirical field data measured in traffic consisting of 100% human-driving vehicles. The physics of the nucleation nature of the F→S transition in automated-driving traffic is associated with a discontinuity in the rate of lane-changing that causes the discontinuity in the rate of over-acceleration. This discontinuous character of over-acceleration leads to both the existence and self-maintaining of synchronized flow at the bottleneck in automated-driving vehicular traffic as well as to the existence at any time instant of a range of highway capacities between some minimum and maximum capacities. Within the capacity range, an F→S transition can be induced; however, when the maximum capacity is exceeded, then after some time-delay a spontaneous F→S transition occurs at the bottleneck. The phases F, S, and J can coexist each other in space and time.

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