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Bratislavske Lekarske Listy 2024Astrocytes undergo morphological and molecular changes in response to numerous pathological conditions.
OBJECTIVE
Astrocytes undergo morphological and molecular changes in response to numerous pathological conditions.
BACKROUND
Increased expression of glial fibrillary acidic protein (GFAP) has been reported as a characteristic feature of reactive astrocytes. However, GFAP-positive cells occur rarely in adult human brain cultures. These cultures are mostly composed of flat GFAP-negative "glia-like" cells, which remain poorly characterized in relation to reactive astrogliosis.
METHODS
We examined the cultures from macroscopically injured and normal brain tissue from patients with brain trauma, gliomas, or brain metastases. Immunofluorescence and immunohistochemical methods were used for reactive astrocytes detection.
RESULTS
The intensity of GFAP-positive staining was higher in reactive astrocytes in the brain tissue surrounding gliomas or metastases and lower in brain tissue damaged by traumatic injury. We did not observe any correlation between GFAP-positive reactive astrocytes in cultures and brain tissue. However, we found rapidly proliferating spindle-shaped cells in cultures prepared from injured brain tissue.
CONCLUSION
Present data demonstrate the unexplained phenomenon of disparate cell morphologies in cultures when prepared either from macroscopically normal or injured human brain tissue. While normal cultures are mainly comprised of flat cells, the cultures from severely damaged brain tissue may be entirely composed of spindle-shaped cells usually classified as fibroblasts. We suggest that this spindle-shaped cellular morphology is not specific for fibroblasts, but it rather can be interpreted as the most favorable shape for rapid cell proliferation under culture conditions. After brain trauma, unknown processes may be triggered, such as induced cell proliferation which can be revealed under culture condition. Accordingly, we conclude that spindle-shaped cells are activated precursors of glial cells (Fig. 3, Ref. 15).
Topics: Humans; Fibroblasts; Glial Fibrillary Acidic Protein; Astrocytes; Brain Injuries; Female; Middle Aged; Male; Adult; Cells, Cultured; Aged; Brain Neoplasms; Brain; Glioma; Neuroglia
PubMed: 38943501
DOI: 10.4149/BLL_2024_63 -
The Journal of Comparative Neurology Jul 2024Dendritic spines are sites of synaptic plasticity and their head size correlates with the strength of the corresponding synapse. We recently showed that the distribution...
Dendritic spines are sites of synaptic plasticity and their head size correlates with the strength of the corresponding synapse. We recently showed that the distribution of spine head sizes follows a lognormal-like distribution even after blockage of activity or plasticity induction. As the cytokine tumor necrosis factor (TNF) influences synaptic transmission and constitutive TNF and receptor (TNF-R)-deficiencies cause changes in spine head size distributions, we tested whether these genetic alterations disrupt the lognormality of spine head sizes. Furthermore, we distinguished between spines containing the actin-modulating protein synaptopodin (SP-positive), which is present in large, strong and stable spines and those lacking it (SP-negative). Our analysis revealed that neither TNF-deficiency nor the absence of TNF-R1, TNF-R2 or TNF-R 1 and 2 (TNF-R1/R2) degrades the general lognormal-like, skewed distribution of spine head sizes (all spines, SP-positive spines, SP-negative spines). However, TNF, TNF-R1 and TNF-R2-deficiency affected the width of the lognormal distribution, and TNF-R1/2-deficiency shifted the distribution to the left. Our findings demonstrate the robustness of the lognormal-like, skewed distribution, which is maintained even in the face of genetic manipulations that alter the distribution of spine head sizes. Our observations are in line with homeostatic adaptation mechanisms of neurons regulating the distribution of spines and their head sizes.
Topics: Animals; Dendritic Spines; Mice; Receptors, Tumor Necrosis Factor, Type I; Mice, Knockout; Dentate Gyrus; Tumor Necrosis Factor-alpha; Mice, Inbred C57BL; Receptors, Tumor Necrosis Factor, Type II; Neurons; Male; Microfilament Proteins
PubMed: 38943486
DOI: 10.1002/cne.25645 -
Advanced Materials (Deerfield Beach,... Jun 2024Films and patterns of 3D-oriented metal-organic frameworks (MOFs) afford well-ordered pore structures extending across centimeter-scale areas. These macroscopic domains...
Films and patterns of 3D-oriented metal-organic frameworks (MOFs) afford well-ordered pore structures extending across centimeter-scale areas. These macroscopic domains of aligned pores are pivotal to enhance diffusion along specific pathways and orient functional guests. The anisotropic properties emerging from this alignment are beneficial for applications in ion conductivity and photonics. However, the structure of 3D-oriented MOF films and patterns can rapidly degrade under humid and acidic conditions. Thus, more durable 3D-ordered porous systems are desired for practical applications. Here, oriented porous polymer films and patterns are prepared by using heteroepitaxially oriented N-functionalized MOF films as precursor materials. The film fabrication protocol utilizes an azide-alkyne cycloaddition on the Cu(AzBPDC)DABCO MOF. The micropatterning protocol exploits the X-ray sensitivity of azide groups in Cu(AzBPDC)DABCO, enabling selective degradation in the irradiated areas. The masked regions of the MOF film retain their N-functionality, allowing for subsequent cross-linking through azide-alkyne coupling. Subsequent acidic treatment removes the Cu ions from the MOF, yielding porous polymer micro-patterns. The polymer has high chemical stability and shows an anisotropic fluorescent response. The use of 3D-oriented MOF systems as precursors for the fabrication of oriented porous polymers will facilitate the progress of optical components for photonic applications. This article is protected by copyright. All rights reserved.
PubMed: 38943469
DOI: 10.1002/adma.202404384 -
Small (Weinheim An Der Bergstrasse,... Jun 2024Conductive flexible hydrogels have attracted immense attentions recently due to their wide applications in wearable sensors. However, the poor mechanical properties of...
Conductive flexible hydrogels have attracted immense attentions recently due to their wide applications in wearable sensors. However, the poor mechanical properties of most conductive polymer limit their utilizations. Herein, a double network hydrogel is fabricated via a self-sorting process with cationic polyacrylamide as the first flexible network and the lantern[3]arene-based hydrogen organic framework nanofibers as the second rigid network. This hydrogel is endowed with good conductivity (0.25 S m) and mechanical properties, such as large Young's modulus (31.9 MPa), fracture elongation (487%) and toughness (6.97 MJ m). The stretchability of this hydrogel is greatly improved after the kirigami cutting, which makes it can be used as flexible strain sensor for monitoring human motions, such as bending of fingers, wrist and elbows. This study not only provides a valuable strategy for the construction of double network hydrogels by lanternarene, but also expands the application of the macrocycle hydrogels to flexible electronics.
PubMed: 38943438
DOI: 10.1002/smll.202404231 -
Angewandte Chemie (International Ed. in... Jun 2024Peptide folding is a dynamic process driven by non-covalent cross-linking leading to functional nanostructures for essential biochemical activities. However, replicating...
Peptide folding is a dynamic process driven by non-covalent cross-linking leading to functional nanostructures for essential biochemical activities. However, replicating this process in synthetic systems is challenging due to the difficulty in mimicking nature's real-time regulation of non-covalent crosslinking for single-chain polymer folding. Here, we address this by employing anionic dithiol building blocks to create macrocyclic disulfides as non-covalent crosslinkers that adapted to the folding process. Initially, small macrocycles facilitated a low degree folding of a polycation. Then, this preorganized structure catalysed the production of larger macrocycles that enhanced the folding conversely. The self-adaptive synthesis was verified through the encapsulation of an anticancer drug, showing an updated production distribution of non-covalent crosslinkers and maximizing drug-loading efficiency against drug-resistant cancer in vitro. Our research advances the understanding of molecular systems by exploring species evolution via the structural dynamics of polymer folding. Additionally, adaptive synthesis enables controlled, sequential folding of synthetic polymers, with the potential to mimic protein functions.
PubMed: 38943429
DOI: 10.1002/anie.202408670 -
Advanced Materials (Deerfield Beach,... Jun 2024The disorder of the macrophage phenotype and the hostile by-product of lactate evoked by pathogenic infection in hypoxic deep wound inevitably lead to the stagnant skin...
The disorder of the macrophage phenotype and the hostile by-product of lactate evoked by pathogenic infection in hypoxic deep wound inevitably lead to the stagnant skin regeneration. In this study, we developed HS-evolving alternately catalytic bio-heterojunction enzyme (AC-BioHJzyme) consisting of CuFeS and lactate oxidase (CuFeS@LOD). AC-BioHJzyme exhibits circular enzyme-mimetic antibacterial (EMA) activity and macrophage re-rousing capability, which can be activated by near-infrared-II (NIR-II) light. In this system, LOD exhausts lactate derived from bacterial anaerobic respiration and generated hydrogen peroxide (HO), which provides an abundant stock for the peroxidase-mimetic activity to convert the produced HO into germicidal •OH. The GPx-mimetic activity endows AC-BioHJzyme with a glutathione consumption property to block the antioxidant systems in bacterial metabolism, while the O provided by the CAT-mimetic activity can generate O under the NIR-II irradiation. Synchronously, the HS gas liberated from CuFeS@LOD under the infectious micromilieu allows the reduction of Fe(III)/Cu(II) to Fe(II)/Cu(І), resulting in sustained circular EMA activity. In vitro and in vivo assays indicate that the CuFeS@LOD AC-BioHJzyme significantly facilitates the infectious cutaneous regeneration by killing bacteria, facilitating epithelialization/collagen deposition, promoting angiogenesis and reprogramming macrophages. This study provides a countermeasure for deep infectious wound healing via circular enzyme-mimetic antibiosis and macrophage re-rousing. This article is protected by copyright. All rights reserved.
PubMed: 38943427
DOI: 10.1002/adma.202405659 -
Nigerian Journal of Clinical Practice Jun 2024The burden of perinatal asphyxia remains high in our environment and when asphyxia is severe, vital organs are affected, with resultant multiorgan hypoxic-iscahemic...
BACKGROUND
The burden of perinatal asphyxia remains high in our environment and when asphyxia is severe, vital organs are affected, with resultant multiorgan hypoxic-iscahemic injury to the heart, the brain, adrenals and other organs.
STUDY AIM
To evaluate for myocardial injury in asphyxiated term neonates with hypoxic ischaemic encephalopathy using serum cardiac troponin-I (cTnI).
METHODS
The study was a hospital-based descriptive cross-sectional study involving sixty term asphyxiated neonates and sixty gestational age-and sex-matched controls. The subjects were term neonates with five-minute Apgar score ≤ 6 and HIE while the controls were healthy term neonates with five-minute Apgar score > 6. Five-minute Apgar score was utilized to classify asphyxia into mild, moderate and severe asphyxia. The degree of encephalopathy was determined by modified Sarnat and Sarnat criteria. The serum cTnI was measured in subjects and controls at 12-24 hours of life using Enzyme-linked immunosorbent assay technique. The serum bilirubin levels were also measured in participants to exclude hyperbilirubinemia.
RESULTS
The median serum cTnI levels was significantly higher in the subjects (0.56ng/mL; 0.25-0.94ng/mL) than in the controls (0.50ng/mL; 0.00-0.67ng/mL), respectively; p=0.001. Similarly, the median serum cTnI level in HIE stage II (0.56ng/mL; 0.38-0.72ng/mL) or III (0.56ng/ml; 0.50-0.94ng/mL) was also significantly higher than the median value in HIE stage I (0.38ng/mL;0.25-0.72ng/mL) or in controls (0.50ng/mL; 0.00-0.67ng/mL); p<0.001. There was significant positive correlation between serum cTnI levels and severity of HIE in asphyxiated neonates (rs = 0.505, p < 0.001).
CONCLUSION
serum cTnI levels were elevated in severely asphyxiated neonates with HIE. The concentration of serum cTnI demonstrated significant positive correlation with HIE severity. Hence, the presence of HIE in asphyxiated neonates should prompt an evaluation for myocardial injury using serum cTnI. Any derangement noted should warrant instituting cardiovascular support in order to improve outcome and reduce asphyxia-related mortality.
Topics: Humans; Infant, Newborn; Asphyxia Neonatorum; Troponin I; Female; Nigeria; Male; Cross-Sectional Studies; Case-Control Studies; Hospitals, Teaching; Apgar Score; Biomarkers; Hypoxia-Ischemia, Brain
PubMed: 38943306
DOI: 10.4103/njcp.njcp_169_24 -
Journal of Cosmetic Dermatology Jun 2024The increasing quest for effective and safe antiaging skincare solutions has led to a surge in the exploration of natural compounds such as phenolic acids. Despite the...
BACKGROUND
The increasing quest for effective and safe antiaging skincare solutions has led to a surge in the exploration of natural compounds such as phenolic acids. Despite the proven efficacy of traditional antiaging ingredients like retinol, their associated side effects have necessitated the search for alternatives.
AIMS
This study aimed to assess the anti-wrinkle efficacy of a standardized phenolic acids polymer extract (PAPE) from propolis, employing both in vitro and clinical methodologies to explore its suitability as a novel antiaging skincare ingredient for sensitive and nonsensitive skin types.
PATIENTS/METHODS
The study comprised of evaluating PAPE effects on key skin health biomarkers in dermal fibroblasts and keratinocytes. A double-blind, randomized clinical trial involving female participants aged 30-70 years assessed the wrinkle-reducing effectiveness of face creams formulated with two concentrations of PAPE (1.5% and 3%) over a 28-day period.
RESULTS
In vitro studies indicated that PAPE could modulate inflammation and tissue remodeling biomarkers. The clinical trial demonstrated that applying PAPE-enriched cream resulted in significant wrinkle reduction, with 25% and 34% improvements for the 1.5% and 3% PAPE formulations, respectively. Subjective feedback from participants further validated the antiaging efficacy and overall satisfaction with the product.
CONCLUSION
Incorporating PAPE offers a compelling antiaging solution, significantly reducing wrinkle depth with a favorable safety profile. The study substantiates PAPE's potential as an effective and safe alternative to conventional antiaging ingredients, aligning with the cosmetic industry's shift toward natural, evidence-based formulations.
PubMed: 38943252
DOI: 10.1111/jocd.16405 -
Journal of Nanobiotechnology Jun 2024Tissue engineered heart valves (TEHVs) demonstrates the potential for tissue growth and remodel, offering particular benefit for pediatric patients. A significant...
Tissue engineered heart valves (TEHVs) demonstrates the potential for tissue growth and remodel, offering particular benefit for pediatric patients. A significant challenge in designing functional TEHV lies in replicating the anisotropic mechanical properties of native valve leaflets. To establish a biomimetic TEHV model, we employed melt-electrowriting (MEW) technology to fabricate an anisotropic PCL scaffold. By integrating the anisotropic MEW-PCL scaffold with bioactive hydrogels (GelMA/ChsMA), we successfully crafted an elastic scaffold with tunable mechanical properties closely mirroring the structure and mechanical characteristics of natural heart valves. This scaffold not only supports the growth of valvular interstitial cells (VICs) within a 3D culture but also fosters the remodeling of extracellular matrix of VICs. The in vitro experiments demonstrated that the introduction of ChsMA improved the hemocompatibility and endothelialization of TEHV scaffold. The in vivo experiments revealed that, compared to their non-hydrogel counterparts, the PCL-GelMA/ChsMA scaffold, when implanted into SD rats, significantly suppressed immune reactions and calcification. In comparison with the PCL scaffold, the PCL-GelMA/ChsMA scaffold exhibited higher bioactivity and superior biocompatibility. The amalgamation of MEW technology and biomimetic design approaches provides a new paradigm for manufacturing scaffolds with highly controllable microstructures, biocompatibility, and anisotropic mechanical properties required for the fabrication of TEHVs.
Topics: Tissue Engineering; Animals; Tissue Scaffolds; Anisotropy; Rats; Rats, Sprague-Dawley; Heart Valves; Hydrogels; Biocompatible Materials; Heart Valve Prosthesis; Polyesters; Cells, Cultured; Humans; Extracellular Matrix; Male
PubMed: 38943185
DOI: 10.1186/s12951-024-02656-5 -
Microbial Ecology Jun 2024Plastic pollution poses a worldwide environmental challenge, affecting wildlife and human health. Assessing the biodegradation capabilities of natural microbiomes in...
Plastic pollution poses a worldwide environmental challenge, affecting wildlife and human health. Assessing the biodegradation capabilities of natural microbiomes in environments contaminated with microplastics is crucial for mitigating the effects of plastic pollution. In this work, we evaluated the potential of landfill leachate (LL) and estuarine sediments (ES) to biodegrade polyethylene (PE), polyethylene terephthalate (PET), and polycaprolactone (PCL), under aerobic, anaerobic, thermophilic, and mesophilic conditions. PCL underwent extensive aerobic biodegradation with LL (99 ± 7%) and ES (78 ± 3%) within 50-60 days. Under anaerobic conditions, LL degraded 87 ± 19% of PCL in 60 days, whereas ES showed minimal biodegradation (3 ± 0.3%). PE and PET showed no notable degradation. Metataxonomics results (16S rRNA sequencing) revealed the presence of highly abundant thermophilic microorganisms assigned to Coprothermobacter sp. (6.8% and 28% relative abundance in anaerobic and aerobic incubations, respectively). Coprothermobacter spp. contain genes encoding two enzymes, an esterase and a thermostable monoacylglycerol lipase, that can potentially catalyze PCL hydrolysis. These results suggest that Coprothermobacter sp. may be pivotal in landfill leachate microbiomes for thermophilic PCL biodegradation across varying conditions. The anaerobic microbial community was dominated by hydrogenotrophic methanogens assigned to Methanothermobacter sp. (21%), pointing at possible syntrophic interactions with Coprothermobacter sp. (a H-producer) during PCL biodegradation. In the aerobic experiments, fungi dominated the eukaryotic microbial community (e.g., Exophiala (41%), Penicillium (17%), and Mucor (18%)), suggesting that aerobic PCL biodegradation by LL involves collaboration between fungi and bacteria. Our findings bring insights on the microbial communities and microbial interactions mediating plastic biodegradation, offering valuable perspectives for plastic pollution mitigation.
Topics: Biodegradation, Environmental; Microbiota; Microplastics; Waste Disposal Facilities; Bacteria; Water Pollutants, Chemical; Polyesters; Geologic Sediments; RNA, Ribosomal, 16S; Estuaries; Polyethylene; Polyethylene Terephthalates
PubMed: 38943017
DOI: 10.1007/s00248-024-02399-8