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PeerJ 2024In the present study, zinc oxide nanoparticles (ZnO-NPs) were synthesized using neem leaf aqueous extracts and characterized using transmission electron microscopy...
In the present study, zinc oxide nanoparticles (ZnO-NPs) were synthesized using neem leaf aqueous extracts and characterized using transmission electron microscopy (TEM), ultraviolet visible spectroscopy (UV-Vis), and dynamic light scattering (DLS). Then compare its efficacy as anticancer and antibacterial agents with chemically synthesized ZnO-NPs and the neem leaf extract used for the green synthesis of ZnO-NPs. The TEM, UV-vis, and particle size confirmed that the developed ZnO-NPs are nanoscale. The chemically and greenly synthesized ZnO-NPs showed their optical absorbance at 328 nm and 380 nm, respectively, and were observed as spherical particles with a size of about 85 nm and 62.5 nm, respectively. HPLC and GC-MS were utilized to identify the bioactive components in the neem leaf aqueous extract employed for the eco-friendly production of ZnO-NPs. The HPLC analysis revealed that the aqueous extract of neem leaf contains 19 phenolic component fractions. The GC-MS analysis revealed the existence of 21 bioactive compounds. The antiproliferative effect of green ZnO-NPs was observed at different concentrations (31.25 µg/mL-1000 µg/mL) on Hct 116 and A 549 cancer cells, with an IC50 value of 111 µg/mL for A 549 and 118 µg/mL for Hct 116. On the other hand, the antibacterial activity against gram-positive and gram-negative bacteria was estimated. The antibacterial result showed that the MIC of green synthesized ZnO-NPs against gram-positive and gram-negative bacteria were 5, and 1 µg/mL. Hence, they could be utilized as effective antibacterial and antiproliferative agents.
Topics: Zinc Oxide; Anti-Bacterial Agents; Plant Extracts; Humans; Plant Leaves; Antineoplastic Agents; Azadirachta; Metal Nanoparticles; Microbial Sensitivity Tests; Green Chemistry Technology; Particle Size; Cell Line, Tumor
PubMed: 38948224
DOI: 10.7717/peerj.17588 -
PeerJ 2024The integration of diagnostic methods holds promise for advancing the surveillance of malaria transmission in both endemic and non-endemic regions. Serological assays...
BACKGROUND
The integration of diagnostic methods holds promise for advancing the surveillance of malaria transmission in both endemic and non-endemic regions. Serological assays emerge as valuable tools to identify and delimit malaria transmission, serving as a complementary method to rapid diagnostic tests (RDT) and thick smear microscopy. Here, we evaluate the potential of antibodies directed against peptides encompassing the entire amino acid sequence of the MSP-1 Sal-I strain as viable serological biomarkers for exposure.
METHODS
We screened peptides encompassing the complete amino acid sequence of the Merozoite Surface Protein 1 (MSP-1) Sal-I strain as potential biomarkers for exposure. Here, immunodominant peptides specifically recognized by antibodies from individuals infected with were identified using the SPOT-synthesis technique followed by immunoblotting. Two 15-mer peptides were selected based on their higher and specific reactivity in immunoblotting assays. Subsequently, peptides p70 and p314 were synthesized in soluble form using SPPS (Solid Phase Peptide Synthesis) and tested by ELISA (IgG, and subclasses).
RESULTS
This study unveils the presence of IgG antibodies against the peptide p314 in most -infected individuals from the Brazilian Amazon region. B-cell epitope prediction further supports the utilization of p314 as a potential biomarker for evaluating malaria transmission, strengthened by its amino acid sequence being part of a conserved block of MSP-1. Indeed, compared to patients infected with and uninfected individuals never exposed to malaria, -infected patients have a notably higher recognition of p314 by IgG1 and IgG3.
Topics: Humans; Malaria, Vivax; Merozoite Surface Protein 1; Plasmodium vivax; Biomarkers; Antibodies, Protozoan; Immunoglobulin G; Adult; Female; Male; Middle Aged; Peptides; Enzyme-Linked Immunosorbent Assay; Young Adult; Adolescent; Amino Acid Sequence
PubMed: 38948214
DOI: 10.7717/peerj.17632 -
Macromolecules Jun 2024The arrangement of crystalline domains in semicrystalline polymers is key to understanding how to optimize the nanostructured morphology for enabling better properties....
The arrangement of crystalline domains in semicrystalline polymers is key to understanding how to optimize the nanostructured morphology for enabling better properties. For example, in polystyrene--poly(ethylene oxide) (PS--PEO), the degree of crystallinity and arrangement of the crystallites within the PEO phase plays a crucial role in determining the physical properties of the electrolyte. Here, we used four-dimensional scanning transmission electron microscopy to directly visualize the crystal domains within the PEO-rich region of the PS--PEO block copolymer and show the relative angle of the domain with respect to the PEO-PS interface. As demonstrated here, our analysis method is applicable to other electron-beam sensitive materials, especially semicrystalline polymers, to unveil their local phase condition and distribution.
PubMed: 38948181
DOI: 10.1021/acs.macromol.3c02231 -
Npj Imaging 2024Patient-derived tumor organoids have emerged as a crucial tool for assessing the efficacy of chemotherapy and conducting preclinical drug screenings. However, the...
Patient-derived tumor organoids have emerged as a crucial tool for assessing the efficacy of chemotherapy and conducting preclinical drug screenings. However, the conventional histological investigation of these organoids necessitates their devitalization through fixation and slicing, limiting their utility to a single-time analysis. Here, we use stimulated Raman histology (SRH) to demonstrate non-destructive, label-free virtual staining of 3D organoids, while preserving their viability and growth. This novel approach provides contrast similar to conventional staining methods, allowing for the continuous monitoring of organoids over time. Our results demonstrate that SRH transforms organoids from one-time use products into repeatable models, facilitating the efficient selection of effective drug combinations. This advancement holds promise for personalized cancer treatment, allowing for the dynamic assessment and optimization of chemotherapy treatments in patient-specific contexts.
PubMed: 38948153
DOI: 10.1038/s44303-024-00019-1 -
Npj Imaging 2024Label-free autofluorescence lifetime is a unique feature of the inherent fluorescence signals emitted by natural fluorophores in biological samples. Fluorescence...
Label-free autofluorescence lifetime is a unique feature of the inherent fluorescence signals emitted by natural fluorophores in biological samples. Fluorescence lifetime imaging microscopy (FLIM) can capture these signals enabling comprehensive analyses of biological samples. Despite the fundamental importance and wide application of FLIM in biomedical and clinical sciences, existing methods for analysing FLIM images often struggle to provide rapid and precise interpretations without reliable references, such as histology images, which are usually unavailable alongside FLIM images. To address this issue, we propose a deep learning (DL)-based approach for generating virtual Hematoxylin and Eosin (H&E) staining. By combining an advanced DL model with a contemporary image quality metric, we can generate clinical-grade virtual H&E-stained images from label-free FLIM images acquired on unstained tissue samples. Our experiments also show that the inclusion of lifetime information, an extra dimension beyond intensity, results in more accurate reconstructions of virtual staining when compared to using intensity-only images. This advancement allows for the instant and accurate interpretation of FLIM images at the cellular level without the complexities associated with co-registering FLIM and histology images. Consequently, we are able to identify distinct lifetime signatures of seven different cell types commonly found in the tumour microenvironment, opening up new opportunities towards biomarker-free tissue histology using FLIM across multiple cancer types.
PubMed: 38948152
DOI: 10.1038/s44303-024-00021-7 -
MLife Jun 2024Cytidine triphosphate synthase (CTPS) plays a pivotal role in the de novo synthesis of cytidine triphosphate (CTP), a fundamental building block for RNA and DNA that is...
Cytidine triphosphate synthase (CTPS) plays a pivotal role in the de novo synthesis of cytidine triphosphate (CTP), a fundamental building block for RNA and DNA that is essential for life. CTPS is capable of directly binding to all four nucleotide triphosphates: adenine triphosphate, uridine triphosphate, CTP, and guanidine triphosphate. Furthermore, CTPS can form cytoophidia in vivo and metabolic filaments in vitro, undergoing regulation at multiple levels. CTPS is considered a potential therapeutic target for combating invasions or infections by viral or prokaryotic pathogens. Utilizing cryo-electron microscopy, we determined the structure of CTPS (ecCTPS) filament in complex with CTP, nicotinamide adenine dinucleotide (NADH), and the covalent inhibitor 6-diazo-5-oxo- l-norleucine (DON), achieving a resolution of 2.9 Å. We constructed a phylogenetic tree based on differences in filament-forming interfaces and designed a variant to validate our hypothesis, providing an evolutionary perspective on CTPS filament formation. Our computational analysis revealed a solvent-accessible ammonia tunnel upon DON binding. Through comparative structural analysis, we discern a distinct mode of CTP binding of ecCTPS that differs from eukaryotic counterparts. Combining biochemical assays and structural analysis, we determined and validated the synergistic inhibitory effects of CTP with NADH or adenine on CTPS. Our results expand our comprehension of the diverse regulatory aspects of CTPS and lay a foundation for the design of specific inhibitors targeting prokaryotic CTPS.
PubMed: 38948148
DOI: 10.1002/mlf2.12119 -
Materials Today. Bio Aug 2024The complex biological process of osseointegration and the bio-inertness of bone implants are the major reasons for the high failure rate of long-term implants, and have...
The complex biological process of osseointegration and the bio-inertness of bone implants are the major reasons for the high failure rate of long-term implants, and have also promoted the rapid development of multifunctional implant coatings in recent years. Herein, through the special design of peptides, we use layer-by-layer assembly technology to simultaneously display two peptides with different biological functions on the implant surface to address this issue. A variety of surface characterization techniques (ellipsometry, atomic force microscopy, photoelectron spectroscopy, dissipation-quartz crystal microbalance) were used to study in detail the preparation process of the dual peptide functional coating and the physical and chemical properties, such as the composition, mechanical modulus, stability, and roughness of the coating. Compared with single peptide functional coatings, dual-peptide functionalized coatings had much better performances on antioxidant, cellular adhesion in early stage, proliferation and osteogenic differentiation in long term, as well as in vivo osteogenesis and osseointegration capabilities. These findings will promote the development of multifunctional designs in bone implant coatings, as a coping strategy for the complexity of biological process during osteointegration.
PubMed: 38948091
DOI: 10.1016/j.mtbio.2024.101108 -
Frontiers in Molecular Biosciences 2024Alzheimer's disease (AD) is a progressive debilitating neurological disorder representing the most common neurodegenerative disease worldwide. Although the exact...
Alzheimer's disease (AD) is a progressive debilitating neurological disorder representing the most common neurodegenerative disease worldwide. Although the exact pathogenic mechanisms of AD remain unresolved, the presence of extracellular amyloid-β peptide 1-42 (Aβ) plaques in the parenchymal and cortical brain is considered one of the hallmarks of the disease. In this work, we investigated the Aβ fibrillogenesis timeline up to 48 h of incubation, providing morphological and chemo-structural characterization of the main assemblies formed during the aggregation process of Aβ, by atomic force microscopy (AFM) and surface enhanced Raman spectroscopy (SERS), respectively. AFM topography evidenced the presence of characteristic protofibrils at early-stages of aggregation, which form peculiar macromolecular networks over time. SERS allowed to track the progressive variation in the secondary structure of the aggregation species involved in the fibrillogenesis and to determine when the β-sheet starts to prevail over the random coil conformation in the aggregation process. Our research highlights the significance of investigating the early phases of fibrillogenesis to better understand the molecular pathophysiology of AD and identify potential therapeutic targets that may prevent or slow down the aggregation process.
PubMed: 38948077
DOI: 10.3389/fmolb.2024.1376411 -
Theranostics 2024Autophagy dysregulation is known to be a mechanism of doxorubicin (DOX)-induced cardiotoxicity (DIC). Mitochondrial-Endoplasmic Reticulum Contacts (MERCs) are where...
Autophagy dysregulation is known to be a mechanism of doxorubicin (DOX)-induced cardiotoxicity (DIC). Mitochondrial-Endoplasmic Reticulum Contacts (MERCs) are where autophagy initiates and autophagosomes form. However, the role of MERCs in autophagy dysregulation in DIC remains elusive. FUNDC1 is a tethering protein of MERCs. We aim to investigate the effect of DOX on MERCs in cardiomyocytes and explore whether it is involved in the dysregulated autophagy in DIC. We employed confocal microscopy and transmission electron microscopy to assess MERCs structure. Autophagic flux was analyzed using the mCherry-EGFP-LC3B fluorescence assay and western blotting for LC3BII. Mitophagy was studied through the mCherry-EGFP-FIS1 fluorescence assay and colocalization analysis between LC3B and mitochondria. A total dose of 18 mg/kg of doxorubicin was administrated in mice to construct a DIC model . Additionally, we used adeno-associated virus (AAV) to cardiac-specifically overexpress FUNDC1. Cardiac function and remodeling were evaluated by echocardiography and Masson's trichrome staining, respectively. DOX blocked autophagic flux by inhibiting autophagosome biogenesis, which could be attributed to the downregulation of FUNDC1 and disruption of MERCs structures. FUNDC1 overexpression restored the blocked autophagosome biogenesis by maintaining MERCs structure and facilitating ATG5-ATG12/ATG16L1 complex formation without altering mitophagy. Furthermore, FUNDC1 alleviated DOX-induced oxidative stress and cardiomyocytes deaths in an autophagy-dependent manner. Notably, cardiac-specific overexpression of FUNDC1 protected DOX-treated mice against adverse cardiac remodeling and improved cardiac function. : In summary, our study identified that FUNDC1-meditated MERCs exerted a cardioprotective effect against DIC by restoring the blocked autophagosome biogenesis. Importantly, this research reveals a novel role of FUNDC1 in enhancing macroautophagy via restoring MERCs structure and autophagosome biogenesis in the DIC model, beyond its previously known regulatory role as an mitophagy receptor.
Topics: Animals; Doxorubicin; Mice; Autophagy; Cardiotoxicity; Myocytes, Cardiac; Endoplasmic Reticulum; Membrane Proteins; Mitochondrial Proteins; Mitochondria; Mitophagy; Male; Autophagosomes; Mice, Inbred C57BL; Disease Models, Animal
PubMed: 38948070
DOI: 10.7150/thno.92771 -
Theranostics 2024: Recent evidence highlights the pivotal role of mitochondrial dysfunction in mood disorders, but the mechanism involved remains unclear. We studied whether the...
: Recent evidence highlights the pivotal role of mitochondrial dysfunction in mood disorders, but the mechanism involved remains unclear. We studied whether the Hippo/YAP/14-3-3η signaling pathway mediates mitochondrial abnormalities that result in the onset of major depressive disorder (MDD) in a mouse model. : The ROC algorithm was used to identify a subpopulation of mice that were exposed to chronic unpredictable mild stress (CUMS) and exhibited the most prominent depressive phenotype (Dep). Electron microscopy, biochemical assays, quantitative PCR, and immunoblotting were used to evaluate synaptic and mitochondrial changes in the basolateral amygdala (BLA). RNA sequencing was used to explore changes in the Hippo pathway and downstream target genes. pharmacological inhibition and immunoprecipitation was used to confirm YAP/14-3-3η interaction and its role in neuronal mitochondrial dysfunction. We used virus-mediated gene overexpression and knockout in YAP transgenic mice to verify the regulatory effect of the Hippo/YAP/14-3-3η pathway on depressive-like behavior. : Transcriptomic data identified a large number of genes and signaling pathways that were specifically altered from the BLA of Dep mice. Dep mice showed notable synaptic impairment in BLA neurons, as well as mitochondrial damage characterized by abnormal mitochondrial morphology, compromised function, impaired biogenesis, and alterations in mitochondrial marker proteins. The Hippo signaling pathway was activated in Dep mice during CUMS, and the transcriptional regulatory activity of YAP was suppressed by phosphorylation of its Ser127 site. 14-3-3η was identified as an important co-regulatory factor of the Hippo/YAP pathway, as it can respond to chronic stress and regulate cytoplasmic retention of YAP. Importantly, the integrated Hippo/YAP/14-3-3η pathway mediated neuronal mitochondrial dysfunction and depressive behavior in Dep mice. : The integrated Hippo/YAP/14-3-3η pathway in the BLA neuron is critical in mediating depressive-like behaviors in mice, suggesting a causal role for this pathway in susceptibility to chronic stress-induced depression. This pathway therefore may present a therapeutic target against mitochondrial dysfunction and synaptic impairment in MDD.
Topics: Animals; Disease Models, Animal; Mice; Mitochondria; YAP-Signaling Proteins; Signal Transduction; Hippo Signaling Pathway; Basolateral Nuclear Complex; Protein Serine-Threonine Kinases; Male; Stress, Psychological; 14-3-3 Proteins; Adaptor Proteins, Signal Transducing; Depressive Disorder, Major; Depression; Mice, Inbred C57BL; Neurons; Mice, Transgenic
PubMed: 38948066
DOI: 10.7150/thno.92676