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1.
J Neurooncol ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251545

RESUMEN

PURPOSE: Standard-of-care for glioblastoma remains surgical debulking followed by temozolomide and radiation. However, many tumors become radio-resistant while radiation damages surrounding brain tissue. Novel therapies are needed to increase the effectiveness of radiation and reduce the required radiation dose. Drug candidate CBL0137 is efficacious against glioblastoma by inhibiting histone chaperone FACT, known to be involved in DNA damage repair. We investigated the combination of CBL0137 and radiation on glioblastoma. METHODS: In vitro, we combined CBL0137 with radiation on U87MG and A1207 glioblastoma cells using the clonogenic assay to evaluate the response to several treatment regimens, and the Fast Halo Assay to examine DNA repair. In vivo, we used the optimum combination treatment regimen to evaluate the response of orthotopic tumors in nude mice. RESULTS: In vitro, the combination of CBL0137 and radiation is superior to either alone and administering CBL0137 two hours prior to radiation, having the drug present during and for a prolonged period post-radiation, is an optimal schedule. CBL0137 inhibits DNA damage repair following radiation and affects the subcellular distribution of histone chaperone ATRX, a molecule involved in DNA repair. In vivo, one dose of CBL0137 is efficacious and the combination of CBL0137 with radiation increases median survival over either monotherapy. CONCLUSIONS: CBL0137 is most effective with radiation for glioblastoma when present at the time of radiation, immediately after and for a prolonged period post-radiation, by inhibiting DNA repair caused by radiation. The combination leads to increased survival making it attractive as a dual therapy.

2.
Colloids Surf B Biointerfaces ; 244: 114165, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39217725

RESUMEN

Recently, we have described the first supermolecular nanoentities of vitamin B12 derivative, viz. monocyano form of heptabutyl cobyrinate, unique nanoparticles with strong noncovalent intermolecular interactions, emerging optical and catalytic properties. Their nearest analogue, heptamethyl cobyrinate (ACCby), exhibits bioactivity. Here, we demonstrate the first example of the formation of nanoparticles of this nucleotide-free analogue of vitamin B12 in protein nanocarriers and neuroprotective activity in vivo of the own nanoform of the drug. The preparation and characterization of nanocarriers based on bovine serum albumin (BSA) loaded with vitamin B12 (viz. cyano- and aquacobalamins) and ACCby were performed. Nucleotide-free analogue of vitamin B12 is tightly retained by the protein structure and exists in an incorporated state in the form of nanoparticles. The effect of encapsulated drugs on the character and severity of primary generalized seizures in rats induced by the pharmacotoxicant thiosemicarbazide was studied. Cyanocobalamin and ACCby exhibited a neuroprotective effect. The best influence of the encapsulation on the effectiveness of the drugs was achieved in the case of AСCby, whose bioavailability as a neuroprotector did not change upon introduction in BSA particles, i.e., 33 % of surviving animals were observed upon ACCby administration in free form and in encapsulated state. No surviving rats were observed without the administration of drugs. Thus, BSA nanocarriers loaded by nanoparticles of nucleotide-free analogues of vitamin B12, including hydrophobic ones, can be recommended for neuroprotection and targeted delivery.


Asunto(s)
Portadores de Fármacos , Nanopartículas , Fármacos Neuroprotectores , Albúmina Sérica Bovina , Vitamina B 12 , Animales , Vitamina B 12/análogos & derivados , Vitamina B 12/química , Vitamina B 12/farmacología , Albúmina Sérica Bovina/química , Nanopartículas/química , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Portadores de Fármacos/química , Ratas , Masculino , Ratas Wistar , Bovinos , Convulsiones/tratamiento farmacológico , Convulsiones/prevención & control
3.
J Cereb Blood Flow Metab ; : 271678X241270531, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39113416

RESUMEN

Cerebrovascular dysfunction following mild traumatic brain injury (mTBI) is understudied relative to other microstructural injuries, especially during neurodevelopment. The blood-oxygen level dependent response was used to investigate cerebrovascular reactivity (CVR) in response to hypercapnia following pediatric mTBI (pmTBI; ages 8-18 years), as well as pseudocontinuous arterial spin labeling to measure cerebral blood flow (CBF). Data were collected ∼1-week (N = 107) and 4 months (N = 73) post-injury. Sex- and age-matched healthy controls (HC) underwent identical examinations at comparable time points (N = 110 and N = 91). Subtle clinical and cognitive deficits existed at ∼1 week that resolved for some, but not all domains at 4 months post-injury. At both visits, pmTBI showed an increased maximal fit between end-tidal CO2 regressor and the cerebrovascular response across multiple regions (primarily fronto-temporal), as well as increased latency to maximal fit in independent regions (primarily posterior). Hypoperfusion was also noted within the bilateral cerebellum. A biphasic relationship existed between CVR amplitude and age (i.e., positive until 14.5 years, negative thereafter) in both gray and white matter, but these neurodevelopment effects did not moderate injury effects. CVR metrics were not associated with post-concussive symptoms or cognitive deficits. In conclusion, cerebrovascular dysfunction may persist for up to four months following pmTBI.

4.
Sensors (Basel) ; 24(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39205125

RESUMEN

In this review, we summarize the latest advances in the design of optical frequency-domain reflectometers (OFDRs), digital signal processing, and sensors based on special optical fibers. We discuss state-of-the-art approaches to improving metrological characteristics, such as spatial resolution, SNR, dynamic range, and the accuracy of determining back reflection coefficients. We also analyze the latest achievements in the OFDR-based sensors: the accuracy of spatial localization of the impact, the error in detecting temperatures, deformation, and other quantities, and the features of separate measurement of various physical quantities. We also pay attention to the trend of mutual integration of frequency-domain optical reflectometry methods with time-domain optical reflectometry, which provides completely new sensing possibilities. We believe that this review may be useful to engineers and scientists focused on developing a lab setup, complete measurement instrument, or sensing system with specific requirements.

5.
J Neurosci Methods ; 411: 110256, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39182516

RESUMEN

BACKGROUND: Although zebrafish are increasingly utilized in biomedicine for CNS disease modelling and drug discovery, this generates big data necessitating objective, precise and reproducible analyses. The artificial intelligence (AI) applications have empowered automated image recognition and video-tracking to ensure more efficient behavioral testing. NEW METHOD: Capitalizing on several AI tools that most recently became available, here we present a novel open-access AI-driven platform to analyze tracks of adult zebrafish collected from in vivo neuropharmacological experiments. For this, we trained the AI system to distinguish zebrafish behavioral patterns following systemic treatment with several well-studied psychoactive drugs - nicotine, caffeine and ethanol. RESULTS: Experiment 1 showed the ability of the AI system to distinguish nicotine and caffeine with 75 % and ethanol with 88 % probability and high (81 %) accuracy following a post-training exposure to these drugs. Experiment 2 further validated our system with additional, previously unexposed compounds (cholinergic arecoline and varenicline, and serotonergic fluoxetine), used as positive and negative controls, respectively. COMPARISON WITH EXISTING METHODS: The present study introduces a novel open-access AI-driven approach to analyze locomotor activity of adult zebrafish. CONCLUSIONS: Taken together, these findings support the value of custom-made AI tools for unlocking full potential of zebrafish CNS drug research by monitoring, processing and interpreting the results of in vivo experiments.


Asunto(s)
Inteligencia Artificial , Cafeína , Descubrimiento de Drogas , Etanol , Nicotina , Pez Cebra , Animales , Nicotina/farmacología , Descubrimiento de Drogas/métodos , Cafeína/farmacología , Etanol/farmacología , Locomoción/efectos de los fármacos , Locomoción/fisiología , Fármacos del Sistema Nervioso Central/farmacología , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología
6.
Curr Microbiol ; 81(9): 293, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090416

RESUMEN

Hot springs are inhabited by specific microbial communities which are reservoirs of novel taxa. In this work strain 4228-RoLT was isolated from the Solnechny hot spring, Uzon Caldera, Kamchatka. Cells of the strain 4228-RoLT were Gram-negative rods forming multicellular filaments. The strain grew optimally at 60 °C and pH 7.0 and fermented various organic compounds including polysaccharides (microcrystalline cellulose, xylan, chitin, starch, dextrin, dextran, beta-glucan, galactomannan, glucomannan, mannan). Major fatty acids were iso-C17:0, C16:0, C18:0, C20:0, iso-C19:0, anteiso-C17:0 and C22:0. Genome of the strain was of 3.25 Mbp with GC content of 54.2%. Based on the whole genome comparisons and phylogenomic analysis the new isolate was affiliated to a novel species of Thermanaerothrix genus within Anaerolineae class of phylum Chloroflexota, for which the name T. solaris sp. nov. was proposed with 4228-RoLT (= VKM B-3776 T = UQM 41594 T = BIM B-2058 T) as the type strain. 114 CAZymes including 43 glycoside hydrolases were found to be encoded in the genome of strain 4228-RoLT. Cell-bound and extracellular enzymes of strain 4228-RoLT were active against starch, dextran, mannan, xylan and various kinds of celluloses, with the highest activity against beta-glucan. Altogether, growth experiments, enzymatic activities determination and genomic analysis suggested that T. solaris strain 4228-RoLT could serve as a source of glycosidases suitable for plant biomass hydrolysis.


Asunto(s)
Composición de Base , Manantiales de Aguas Termales , Filogenia , Manantiales de Aguas Termales/microbiología , Hidrólisis , Genoma Bacteriano , Ácidos Grasos/metabolismo , ARN Ribosómico 16S/genética , Polisacáridos/metabolismo , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana
7.
Polymers (Basel) ; 16(15)2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39125256

RESUMEN

Organosilicate glass (OSG) films are a critical component in modern electronic devices, with their electrical properties playing a crucial role in device performance. This comprehensive review systematically examines the influence of chemical composition, vacuum ultraviolet (VUV) irradiation, and plasma treatment on the electrical properties of these films. Through an extensive survey of literature and experimental findings, we elucidate the intricate interplay between these factors and the resulting alterations in electrical conductivity, dielectric constant, and breakdown strength of OSG films. Key focus areas include the impact of diverse organic moieties incorporated into the silica matrix, the effects of VUV irradiation on film properties, and the modifications induced by various plasma treatment techniques. Furthermore, the underlying mechanisms governing these phenomena are discussed, shedding light on the complex molecular interactions and structural rearrangements occurring within OSG films under different environmental conditions. It is shown that phonon-assisted electron tunneling between adjacent neutral traps provides a more accurate description of charge transport in OSG low-k materials compared to the previously reported Fowler-Nordheim mechanism. Additionally, the quality of low-k materials significantly influences the behavior of leakage currents. Materials retaining residual porogens or adsorbed water on pore walls show electrical conductivity directly correlated with pore surface area and porosity. Conversely, porogen-free materials, developed by Urbanowicz, exhibit leakage currents that are independent of porosity. This underscores the critical importance of considering internal defects such as oxygen-deficient centers (ODC) or similar entities in understanding the electrical properties of these materials.

8.
Brain Behav Immun ; 122: 345-352, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39163909

RESUMEN

Neuroinflammation is a key component underlying multiple neurological disorders, yet non-invasive and cost-effective assessment of in vivo neuroinflammatory processes in the central nervous system remains challenging. Diffusion weighted magnetic resonance spectroscopy (dMRS) has shown promise in addressing these challenges by measuring diffusivity properties of different neurometabolites, which can reflect cell-specific morphologies. Prior work has demonstrated dMRS utility in capturing microglial reactivity in the context of lipopolysaccharide (LPS) challenges and serious neurological disorders, detected as changes of microglial metabolite diffusivity properties. However, the extent to which such dMRS metrics are capable of detecting subtler and more nuanced levels of neuroinflammation in populations without overt neuropathology is unknown. Here we examined the relationship between intrinsic, gut-derived levels of systemic LPS and dMRS-based apparent diffusion coefficients (ADC) of choline, creatine, and N-acetylaspartate (NAA) in two brain regions: the thalamus and the corona radiata. Higher plasma LPS concentrations were significantly associated with increased ADC of choline and NAA in the thalamic region, with no such relationships observed in the corona radiata for any of the metabolites examined. As such, dMRS may have the sensitivity to measure microglial reactivity across populations with highly variable levels of neuroinflammation, and holds promising potential for widespread applications in both research and clinical settings.


Asunto(s)
Colina , Lipopolisacáridos , Espectroscopía de Resonancia Magnética , Microglía , Lipopolisacáridos/farmacología , Microglía/metabolismo , Animales , Colina/metabolismo , Masculino , Espectroscopía de Resonancia Magnética/métodos , Enfermedades Neuroinflamatorias/metabolismo , Creatina/metabolismo , Ácido Aspártico/metabolismo , Ácido Aspártico/análogos & derivados , Encéfalo/metabolismo , Imagen de Difusión por Resonancia Magnética/métodos , Tálamo/metabolismo , Femenino
9.
Acta Neuropathol ; 148(1): 3, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980423

RESUMEN

This study investigates various pathological tau isoforms in the retina of individuals with early and advanced Alzheimer's disease (AD), exploring their connection with disease status. Retinal cross-sections from predefined superior-temporal and inferior-temporal subregions and corresponding brains from neuropathologically confirmed AD patients with a clinical diagnosis of either mild cognitive impairment (MCI) or dementia (n = 45) were compared with retinas from age- and sex-matched individuals with normal cognition (n = 30) and non-AD dementia (n = 4). Retinal tau isoforms, including tau tangles, paired helical filament of tau (PHF-tau), oligomeric-tau (Oligo-tau), hyperphosphorylated-tau (p-tau), and citrullinated-tau (Cit-tau), were stereologically analyzed by immunohistochemistry and Nanostring GeoMx digital spatial profiling, and correlated with clinical and neuropathological outcomes. Our data indicated significant increases in various AD-related pretangle tau isoforms, especially p-tau (AT8, 2.9-fold, pS396-tau, 2.6-fold), Cit-tau at arginine residue 209 (CitR209-tau; 4.1-fold), and Oligo-tau (T22+, 9.2-fold), as well as pretangle and mature tau tangle forms like MC-1-positive (1.8-fold) and PHF-tau (2.3-fold), in AD compared to control retinas. MCI retinas also exhibited substantial increases in Oligo-tau (5.2-fold), CitR209-tau (3.5-fold), and pS396-tau (2.2-fold). Nanostring GeoMx analysis confirmed elevated retinal p-tau at epitopes: Ser214 (2.3-fold), Ser396 (2.6-fold), Ser404 (2.4-fold), and Thr231 (1.8-fold), particularly in MCI patients. Strong associations were found between retinal tau isoforms versus brain pathology and cognitive status: a) retinal Oligo-tau vs. Braak stage, neurofibrillary tangles (NFTs), and CDR cognitive scores (ρ = 0.63-0.71), b) retinal PHF-tau vs. neuropil threads (NTs) and ABC scores (ρ = 0.69-0.71), and c) retinal pS396-tau vs. NTs, NFTs, and ABC scores (ρ = 0.67-0.74). Notably, retinal Oligo-tau strongly correlated with retinal Aß42 and arterial Aß40 forms (r = 0.76-0.86). Overall, this study identifies and quantifies diverse retinal tau isoforms in MCI and AD patients, underscoring their link to brain pathology and cognition. These findings advocate for further exploration of retinal tauopathy biomarkers to facilitate AD detection and monitoring via noninvasive retinal imaging.


Asunto(s)
Enfermedad de Alzheimer , Isoformas de Proteínas , Retina , Proteínas tau , Humanos , Proteínas tau/metabolismo , Masculino , Femenino , Anciano , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/metabolismo , Retina/patología , Retina/metabolismo , Anciano de 80 o más Años , Disfunción Cognitiva/patología , Disfunción Cognitiva/metabolismo , Persona de Mediana Edad , Ovillos Neurofibrilares/patología , Ovillos Neurofibrilares/metabolismo , Encéfalo/patología , Encéfalo/metabolismo
10.
Urology ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39067637

RESUMEN

OBJECTIVE: To perform endoscopy in patients with urinary diversions requires specific endoscopic skills, which can currently only be gained in clinical practice. We created a 3D-printed ex vivo ileal conduit model (stoma and conduit with ureters and 2 kidneys) to simulate "conduitoscopy" and evaluated the realism and limitations of the model. METHODS: Accurate anatomical features were represented using an appropriate reusable design, realistic mechanical qualities with several material types, and 3D-printed components. Different models of bowel and ureters were assessed by the subject-matter experts (SME). The final ileal conduit model (Wallace 1 type anastomosis) was evaluated by 18 SMEs. RESULTS: Most experts gave their approval to the view of the stoma, as well as the appearance of the bowel, ureteric, and pelvicalyceal systems. A total of 72.1% of SMEs approved the ureteric endoscopic view compared to about 66% who accepted the endoscopic examination of the bowel. The model's overall appearance was good for 61.1% and excellent for 38.8% of experts. CONCLUSION: Conduitoscopy simulation training can now be facilitated using our novel and unique cutting-edge 3D-printed model. We created a model that is highly anatomically accurate and workable. In our study, anatomical and visual realism was demonstrated. The next step would be increasing the length of the conduit and conduct a validation study.

11.
ACS Omega ; 9(26): 27987-27997, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38973853

RESUMEN

Metal nanoparticles are widely used as heterogeneous catalysts to activate adsorbed molecules and reduce the energy barrier of the reaction. Reaction product yield depends on the interplay between elementary processes: adsorption, activation, desorption, and reaction. These processes, in turn, depend on the inlet gas composition, temperature, and pressure. At a steady state, the active surface sites may be inaccessible due to adsorbed reagents. Periodic regime may thus improve the yield, but the appropriate period and waveform are not known in advance. Dynamic control should account for surface and atmospheric modifications and adjust reaction parameters according to the current state of the system and its history. In this work, we applied a reinforcement learning algorithm to control CO oxidation on a palladium catalyst. The policy gradient algorithm was trained in the theoretical environment, parametrized from experimental data. The algorithm learned to maximize the CO2 formation rate based on CO and O2 partial pressures for several successive time steps. Within a unified approach, we found optimal stationary, periodic, and nonperiodic regimes for different problem formulations and gained insight into why the dynamic regime can be preferential. In general, this work contributes to the task of popularizing the reinforcement learning approach in the field of catalytic science.

12.
Nucleic Acids Res ; 52(15): 8687-8701, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39011883

RESUMEN

Nonsense mutations account for >10% of human genetic disorders, including cystic fibrosis, Alagille syndrome, and Duchenne muscular dystrophy. A nonsense mutation results in the expression of a truncated protein, and therapeutic strategies aim to restore full-length protein expression. Most strategies under development, including small-molecule aminoglycosides, suppressor tRNAs, or the targeted degradation of termination factors, lack mRNA target selectivity and may poorly differentiate between nonsense and normal stop codons, resulting in off-target translation errors. Here, we demonstrate that antisense oligonucleotides can stimulate readthrough of disease-causing nonsense codons, resulting in high yields of full-length protein in mammalian cellular lysate. Readthrough efficiency depends on the sequence context near the stop codon and on the precise targeting position of an oligonucleotide, whose interaction with mRNA inhibits peptide release to promote readthrough. Readthrough-inducing antisense oligonucleotides (R-ASOs) enhance the potency of non-specific readthrough agents, including aminoglycoside G418 and suppressor tRNA, enabling a path toward target-specific readthrough of nonsense mutations in CFTR, JAG1, DMD, BRCA1 and other mutant genes. Finally, through systematic chemical engineering, we identify heavily modified fully functional R-ASO variants, enabling future therapeutic development.


Asunto(s)
Codón sin Sentido , Regulador de Conductancia de Transmembrana de Fibrosis Quística , Oligonucleótidos Antisentido , ARN Mensajero , Codón sin Sentido/genética , Oligonucleótidos Antisentido/genética , Humanos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Biosíntesis de Proteínas/efectos de los fármacos , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Distrofina/genética , Células HEK293 , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/terapia , Fibrosis Quística/genética , Fibrosis Quística/tratamiento farmacológico , Gentamicinas
13.
J Biomed Sci ; 31(1): 75, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39044206

RESUMEN

BACKGROUND: Among the non-traditional antibacterial agents in development, only a few targets critical Gram-negative bacteria such as carbapenem-resistant Pseudomonas aeruginosa, Acinetobacter baumannii or cephalosporin-resistant Enterobacteriaceae. Endolysins and their genetically modified versions meet the World Health Organization criteria for innovation, have a novel mode of antibacterial action, no known bacterial cross-resistance, and are being intensively studied for application against Gram-negative pathogens. METHODS: The study presents a multidisciplinary approach, including genetic engineering of LysECD7-SMAP and production of recombinant endolysin, its analysis by crystal structure solution following molecular dynamics simulations and evaluation of antibacterial properties. Two types of antimicrobial dosage forms were formulated, resulting in lyophilized powder for injection and hydroxyethylcellulose gel for topical administration. Their efficacy was estimated in the treatment of sepsis, and pneumonia models in BALB/c mice, diabetes-associated wound infection in the leptin receptor-deficient db/db mice and infected burn wounds in rats. RESULTS: In this work, we investigate the application strategies of the engineered endolysin LysECD7-SMAP and its dosage forms evaluated in preclinical studies. The catalytic domain of the enzyme shares the conserved structure of endopeptidases containing a putative antimicrobial peptide at the C-terminus of polypeptide chain. The activity of endolysins has been demonstrated against a range of pathogens, such as Klebsiella pneumoniae, A. baumannii, P. aeruginosa, Staphylococcus haemolyticus, Achromobacter spp, Burkholderia cepacia complex and Haemophylus influenzae, including those with multidrug resistance. The efficacy of candidate dosage forms has been confirmed in in vivo studies. Some aspects of the interaction of LysECD7-SMAP with cell wall molecular targets are also discussed. CONCLUSIONS: Our studies demonstrate the potential of LysECD7-SMAP therapeutics for the systemic or topical treatment of infectious diseases caused by susceptible Gram-negative bacterial species and are critical to proceed LysECD7-SMAP-based antimicrobials trials to advanced stages.


Asunto(s)
Endopeptidasas , Bacterias Gramnegativas , Infecciones por Bacterias Gramnegativas , Ratones Endogámicos BALB C , Animales , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Ratones , Endopeptidasas/farmacología , Endopeptidasas/administración & dosificación , Bacterias Gramnegativas/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Ratas , Masculino , Ingeniería de Proteínas/métodos
14.
Chemphyschem ; : e202400266, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38938183

RESUMEN

An electro-active copolymer of methyl methacrylate and 2-((4-acroylpiperazine-1-yl)methyl)-9H-thioxanthene-9-one (poly(MMA-co-ThS)) was synthesized by radical polymerization. The copolymer has good solubility in most organic solvents, thermal stability up to 282 °C and excellent ability to form thin films on silicon wafers. Poly(MMA-co-ThS) films exhibited an electrochemical and electrochromic activity resulting in the formation of long-lived radical anion states of pendant thioxanthone groups inside the film. These states exhibit optical transitions in the visible region as a broad optical absorption band, 500<λ<900 nm (1.38

15.
Sci Rep ; 14(1): 12789, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38834640

RESUMEN

Emergent design failures are ubiquitous in complex systems, and often arise when system elements cluster. Approaches to systematically reduce clustering could improve a design's resilience, but reducing clustering is difficult if it is driven by collective interactions among design elements. Here, we use techniques from statistical physics to identify mechanisms by which spatial clusters of design elements emerge in complex systems modelled by heterogeneous networks. We find that, in addition to naive, attraction-driven clustering, heterogeneous networks can exhibit emergent, repulsion-driven clustering. We draw quantitative connections between our results on a model system in naval engineering to entropy-driven phenomena in nanoscale self-assembly, and give a general argument that the clustering phenomena we observe should arise in many distributed systems. We identify circumstances under which generic design problems will exhibit trade-offs between clustering and uncertainty in design objectives, and we present a framework to identify and quantify trade-offs to manage clustering vulnerabilities.

16.
Eur Spine J ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874639

RESUMEN

PURPOSE: To analyze of the results of spine surgical treatment of athletes with lumbar degenerative disease and development of a surgical strategy based on the preoperative symptoms and radiological changes in the lumbar spine. METHODS: For 114 athletes with lumbar degenerative disease were included in the present study. Four independent groups were studied: (1) microsurgical/endoscopic discectomy (n = 35); (2) PRP therapy in facet joints (n = 41); (3) total disc replacement (n = 11); (4) lumbar interbody fusion (n = 27). We evaluated postoperative clinical outcomes and preoperative radiological results. The average postoperative follow-up was 5 (3;6), 3.5 (3;5), 3 (2;4) and 4 (3;5) years, respectively. The analysis included an assessment of clinical outcomes (initial clinical symptoms, chronic pain syndrome level according to the VAS, quality of life according to the SF-36 questionnaire, degree of tolerance to physical activity according to the subjective Borg Rating of Perceived Exertion Scale) and radiological data (Dynamic Slip, Dynamic Segmental Angle, degenerative changes in the facet joint according to the Fujiwara classification and disc according to the Pfirrmann classification; changes in the diffusion coefficient using diffusion-weighted MRI). RESULTS: The median and 25-75% quartiles timing of return to sports were 12.6 (10.2;14.1), 2.8 (2.4;3.7), 9 (6;12), and 14 (9;17) weeks, respectively. We examined the type of surgical treatment utilized, as well as the preoperative clinical symptoms, severity of degenerative changes in the intervertebral disc and facet joint, the timing of return to sports, the level of pain syndrome, the quality of life according to SF-36, and the degree of tolerance to physical activity. We then developed a surgical strategy based on individual preoperative neurological function and lumbar morphological changes. CONCLUSIONS: In this retrospective study, we report clinical results of four treatment options of lumbar spine degenerative disease in athletes. The use of developed patient selection criteria for the analyzed surgical techniques is aimed at minimizing return-to-play times.

17.
Biochemistry (Mosc) ; 89(5): 853-861, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38880646

RESUMEN

Tumor necrosis factor (TNF) is one of many cytokines - protein molecules responsible for communication between the cells of immune system. TNF was discovered and given its grand name because of its striking antitumor effects in experimental systems, but its main physiological functions in the context of whole organism turned out to be completely unrelated to protection against tumors. This short review discusses "man-made" mouse models generated by early genome-editing technologies, which enabled us to establish true functions of TNF in health and certain diseases as well as to unravel potential strategies for improving therapy of TNF-dependent diseases.


Asunto(s)
Factor de Necrosis Tumoral alfa , Animales , Humanos , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Ratones , Edición Génica/métodos , Neoplasias/inmunología , Neoplasias/genética , Neoplasias/terapia
18.
Viruses ; 16(6)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38932165

RESUMEN

Recently, high-throughput sequencing of influenza A viruses has become a routine test. It should be noted that the extremely high diversity of the influenza A virus complicates the task of determining the sequences of all eight genome segments. For a fast and accurate analysis, it is necessary to select the most suitable reference for each segment. At the same time, there is no standardized method in the field of decoding sequencing results that allows the user to update the sequence databases to which the reads obtained by virus sequencing are compared. The IAVCP (influenza A virus consensus and phylogeny) was developed with the goal of automatically analyzing high-throughput sequencing data of influenza A viruses. Its goals include the extraction of a consensus genome directly from paired raw reads. In addition, the pipeline enables the identification of potential reassortment events in the evolutionary history of the virus of interest by analyzing the topological structure of phylogenetic trees that are automatically reconstructed.


Asunto(s)
Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento , Virus de la Influenza A , Filogenia , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Virus de la Influenza A/genética , Virus de la Influenza A/clasificación , Humanos , Genómica/métodos , Gripe Humana/virología , Biología Computacional/métodos
19.
Sci Data ; 11(1): 635, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879569

RESUMEN

Pulmonary hypertension (PH) is a syndrome complex that accompanies a number of diseases of different etiologies, associated with basic mechanisms of structural and functional changes of the pulmonary circulation vessels and revealed pressure increasing in the pulmonary artery. The structural changes in the pulmonary circulation vessels are the main limiting factor determining the prognosis of patients with PH. Thickening and irreversible deposition of collagen in the pulmonary artery branches walls leads to rapid disease progression and a therapy effectiveness decreasing. In this regard, histological examination of the pulmonary circulation vessels is critical both in preclinical studies and clinical practice. However, measurements of quantitative parameters such as the average vessel outer diameter, the vessel walls area, and the hypertrophy index claimed significant time investment and the requirement for specialist training to analyze micrographs. A dataset of pulmonary circulation vessels for pathology assessment using semantic segmentation techniques based on deep-learning is presented in this work. 609 original microphotographs of vessels, numerical data from experts' measurements, and microphotographs with outlines of these measurements for each of the vessels are presented. Furthermore, here we cite an example of a deep learning pipeline using the U-Net semantic segmentation model to extract vascular regions. The presented database will be useful for the development of new software solutions for the analysis of histological micrograph.


Asunto(s)
Aprendizaje Profundo , Hipertensión Pulmonar , Arteria Pulmonar , Hipertensión Pulmonar/diagnóstico por imagen , Arteria Pulmonar/diagnóstico por imagen , Humanos , Microscopía , Circulación Pulmonar
20.
Diagnostics (Basel) ; 14(11)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38893642

RESUMEN

BACKGROUND: Neisseria meningitidis (meningococcus) is a Gram-negative bacterium that colonises the nasopharynx of about 10% of the healthy human population. Under certain conditions, it spreads into the body, causing infections with high morbidity and mortality rates. Although the capsule is the key virulence factor, unencapsulated strains have proved to possess significant clinical implications as well. Meningococcal meningitis is a primarily human infection, with limited animal models that are dependent on a variety of parameters such as bacterial virulence and mouse strain. In this study, we aimed to develop a murine Neisseria meningitidis meningitis model to be used in the study of various antimicrobial compounds. METHOD: We used a capsule-deficient Neisseria meningitidis strain that was thoroughly analysed through various methods. The bacterial strain was incubated for 48 h in brain-heart infusion (BHI) broth before being concentrated and injected intracisternally to bypass the blood-brain barrier in CD-1 mice. This prolonged incubation time was a key factor in increasing the virulence of the bacterial strain. A total of three more differently prepared inoculums were tested to further solidify the importance of the protocol (a 24-h incubated inoculum, a diluted inoculum, and an inactivated inoculum). Antibiotic treatment groups were also established. The clinical parameters and number of deaths were recorded over a period of 5 days, and comatose mice with no chance of recovery were euthanised. RESULTS: The bacterial strain was confirmed to have no capsule but was found to harbour a total of 56 genes coding virulence factors, and its antibiotic susceptibility was established. Meningitis was confirmed through positive tissue culture and histological evaluation, where specific lesions were observed, such as perivascular sheaths with inflammatory infiltrate. In the treatment groups, survival rates were significantly higher (up to 81.25% in one of the treatment groups compared to 18.75% in the control group). CONCLUSION: We managed to successfully develop a cost-efficient murine (using simple CD-1 mice instead of expensive transgenic mice) meningococcal meningitis model using an unencapsulated strain with a novel method of preparation.

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