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PloS One 2024Cluster regularly interspaced short palindromic repeats and CRISPR associated protein 9 (CRISPR-Cas9) is a promising tool for antimicrobial re-sensitization by...
Cluster regularly interspaced short palindromic repeats and CRISPR associated protein 9 (CRISPR-Cas9) is a promising tool for antimicrobial re-sensitization by inactivating antimicrobial resistance (AMR) genes of bacteria. Here, we programmed CRISPR-Cas9 with common spacers to target predominant blaCTX-M variants in group 1 and group 9 and their promoter in an Escherichia coli model. The CRISPR-Cas9 was delivered by non-replicative phagemid particles from a two-step process, including insertion of spacer in CRISPR and construction of phagemid vector. Spacers targeting blaCTX-M promoters and internal sequences of blaCTX-M group 1 (blaCTX-M-15 and -55) and group 9 (blaCTX-M-14, -27, -65, and -90) were cloned into pCRISPR and phagemid pRC319 for spacer evaluation and phagemid particle production. Re-sensitization and plasmid clearance were mediated by the spacers targeting internal sequences of each group, resulting in 3 log10 to 4 log10 reduction of the ratio of resistant cells, but not by those targeting the promoters. The CRISPR-Cas9 delivered by modified ΦRC319 particles were capable of re-sensitizing E. coli K-12 carrying either blaCTX-M group 1 or group 9 in a dose-dependent manner from 0.1 to 100 multiplicity of infection (MOI). In conclusion, CRISPR-Cas9 system programmed with well-designed spacers targeting multiple variants of AMR gene along with a phage-based delivery system could eliminate the widespread blaCTX-M genes for efficacy restoration of available third-generation cephalosporins by reversal of resistance in bacteria.
Topics: CRISPR-Cas Systems; Escherichia coli; Bacteriophages; beta-Lactamases; Escherichia coli Proteins; Plasmids; Promoter Regions, Genetic; Gene Editing; Anti-Bacterial Agents
PubMed: 38753729
DOI: 10.1371/journal.pone.0303555 -
Journal of Taibah University Medical... Jun 2024Alzheimer's disease (AD), is characterised by two major hallmarks: the formation of extracellular β-amyloid (Aβ) plaques and the hyperphosphorylation of tau protein,... (Review)
Review
Alzheimer's disease (AD), is characterised by two major hallmarks: the formation of extracellular β-amyloid (Aβ) plaques and the hyperphosphorylation of tau protein, thus leading to the formation of neurofibrillary tangles. These hallmarks cause synaptic loss, neuronal damage, and the development of neuroinflammation and oxidative stress, which promote AD progression. Thus, the goal of treating AD is eliminating these hallmarks, to prevent AD progression and decrease symptoms. However, current available therapies provide symptomatic relief rather than treating the underlying cause of the disease, because the restrictive nature of the blood brain barrier (BBB) impedes the entry of drugs, thereby affecting drug efficacy and bioavailability. Researchers are focusing on developing new therapeutic approaches to bypass the BBB, for achieving site-specific drug delivery with the highest possible bioavailability and the lowest adverse effects. Recently explored therapeutic strategies include use of biologic agents such as monoclonal antibodies. Aducanumab, a strong candidate for treating AD, has been granted accelerated Food and Drug Administration approval; however, safety concerns may hinder its future use. Thus, nanotechnological approaches have led to a new era of AD treatment. Nanoparticles (NPs), because of their small particle size, can cross the BBB, thus enhancing drug pharmacokinetic properties and enabling targeted drug delivery. Polymeric NPs have been extensively studied, because of their simple production, biodegradability, biocompatibility, and unique architecture. These NPs provide a flexible vesicle that can be easily tailored to achieve desired physicochemical features. In this review, various types of polymer-based-NPs are discussed, highlighting the properties of fabricated NPs, which have multiple benefits in AD treatment, including anti-amyloid, antioxidant, and anti-inflammatory effects.
PubMed: 38736898
DOI: 10.1016/j.jtumed.2024.04.004 -
International Journal of Molecular... May 2024Herpes simplex virus (HSV) infections are highly widespread among humans, producing symptoms ranging from ulcerative lesions to severe diseases such as blindness and...
Herpes simplex virus (HSV) infections are highly widespread among humans, producing symptoms ranging from ulcerative lesions to severe diseases such as blindness and life-threatening encephalitis. At present, there are no vaccines available, and some existing antiviral treatments can be ineffective or lead to adverse effects. As a result, there is a need for new anti-HSV drugs. In this report, the in vitro anti-HSV effect of 9,9'-norharmane dimer (nHo-dimer), which belongs to the β-carboline (βC) alkaloid family, was evaluated. The dimer exhibited no virucidal properties and did not impede either the attachment or penetration steps of viral particles. The antiviral effect was only exerted under the constant presence of the dimer in the incubation media, and the mechanism of action was found to involve later events of virus infection. Analysis of fluorescence lifetime imaging data showed that the nHo-dimer internalized well into the cells when present in the extracellular incubation medium, with a preferential accumulation into perinuclear organelles including mitochondria. After washing the host cells with fresh medium free of nHo-dimer, the signal decreased, suggesting the partial release of the compound from the cells. This agrees with the observation that the antiviral effect is solely manifested when the alkaloid is consistently present in the incubation media.
Topics: Antiviral Agents; Chlorocebus aethiops; Humans; Vero Cells; Animals; Simplexvirus; Herpes Simplex; Carbolines; Herpesvirus 1, Human; Harmine
PubMed: 38732185
DOI: 10.3390/ijms25094966 -
International Journal of Molecular... Apr 2024Based on the need for radiobiological databases, in this work, we mined experimental ionizing radiation data of human cells treated with X-rays, γ-rays, carbon ions,...
Based on the need for radiobiological databases, in this work, we mined experimental ionizing radiation data of human cells treated with X-rays, γ-rays, carbon ions, protons and α-particles, by manually searching the relevant literature in PubMed from 1980 until 2024. In order to calculate normal and tumor cell survival and coefficients of the linear quadratic (LQ) established model, as well as the initial values of the double-strand breaks (DSBs) in DNA, we used WebPlotDigitizer and Python programming language. We also produced complex DNA damage results through the fast Monte Carlo code MCDS in order to complete any missing data. The calculated / values are in good agreement with those valued reported in the literature, where shows a relatively good association with linear energy transfer (LET), but not . In general, a positive correlation between DSBs and LET was observed as far as the experimental values are concerned. Furthermore, we developed a biophysical prediction model by using machine learning, which showed a good performance for , while it underscored LET as the most important feature for its prediction. In this study, we designed and developed the novel radiobiological 'RadPhysBio' database for the prediction of irradiated cell survival ( and coefficients of the LQ model). The incorporation of machine learning and repair models increases the applicability of our results and the spectrum of potential users.
Topics: Humans; Cell Survival; Radiation, Ionizing; Radiobiology; DNA Breaks, Double-Stranded; Linear Energy Transfer; Databases, Factual; Monte Carlo Method
PubMed: 38731948
DOI: 10.3390/ijms25094729 -
Molecules (Basel, Switzerland) Apr 2024Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid beta (A) plaques in the brain. A is the main component...
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid beta (A) plaques in the brain. A is the main component of A plaque, which is toxic to neuronal cells. Si nanowires (Si NWs) have the advantages of small particle size, high specific surface area, and good biocompatibility, and have potential application prospects in suppressing A aggregation. In this study, we employed the vapor-liquid-solid (VLS) growth mechanism to grow Si NWs using Au nanoparticles as catalysts in a plasma-enhanced chemical vapor deposition (PECVD) system. Subsequently, these Si NWs were transferred to a phosphoric acid buffer solution (PBS). We found that Si NWs significantly reduced cell death in PC12 cells (rat adrenal pheochromocytoma cells) induced by A oligomers via double staining with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and fluorescein diacetate/propyl iodide (FDA/PI). Most importantly, pre-incubated Si NWs largely prevented A oligomer-induced PC12 cell death, suggesting that Si NWs exerts an anti-A neuroprotective effect by inhibiting A aggregation. The analysis of Fourier Transform Infrared (FTIR) results demonstrates that Si NWs reduce the toxicity of fibrils and oligomers by intervening in the formation of -sheet structures, thereby protecting the viability of nerve cells. Our findings suggest that Si NWs may be a potential therapeutic agent for AD by protecting neuronal cells from the toxicity of A.
Topics: Amyloid beta-Peptides; Nanowires; Animals; PC12 Cells; Rats; Silicon; Peptide Fragments; Cell Survival; Neuroprotective Agents; Protein Aggregates; Alzheimer Disease
PubMed: 38731472
DOI: 10.3390/molecules29091980 -
Molecular Cancer May 2024DLL3 acts as an inhibitory ligand that downregulates Notch signaling and is upregulated by ASCL1, a transcription factor prevalent in the small-cell lung cancer (SCLC)... (Review)
Review
DLL3 acts as an inhibitory ligand that downregulates Notch signaling and is upregulated by ASCL1, a transcription factor prevalent in the small-cell lung cancer (SCLC) subtype SCLC-A. Currently, the therapeutic strategies targeting DLL3 are varied, including antibody-drug conjugates (ADCs), bispecific T-cell engagers (BiTEs), and chimeric antigen receptor (CAR) T-cell therapies. Although rovalpituzumab tesirine (Rova-T) showed promise in a phase II study, it failed to produce favorable results in subsequent phase III trials, leading to the cessation of its development. Conversely, DLL3-targeted BiTEs have garnered significant clinical interest. Tarlatamab, for instance, demonstrated enhanced response rates and progression-free survival compared to the standard of care in a phase II trial; its biologics license application (BLA) is currently under US Food and Drug Administration (FDA) review. Numerous ongoing phase III studies aim to further evaluate tarlatamab's clinical efficacy, alongside the development of novel DLL3-targeted T-cell engagers, both bispecific and trispecific. CAR-T cell therapies targeting DLL3 have recently emerged and are undergoing various preclinical and early-phase clinical studies. Additionally, preclinical studies have shown promising efficacy for DLL3-targeted radiotherapy, which employs β-particle-emitting therapeutic radioisotopes conjugated to DLL3-targeting antibodies. DLL3-targeted therapies hold substantial potential for SCLC management. Future clinical trials will be crucial for comparing treatment outcomes among various approaches and exploring combination therapies to improve patient survival outcomes.
Topics: Humans; Small Cell Lung Carcinoma; Immunoconjugates; Lung Neoplasms; Radioimmunotherapy; Intracellular Signaling Peptides and Proteins; Animals; Membrane Proteins; Immunotherapy; Precision Medicine; Molecular Targeted Therapy
PubMed: 38730427
DOI: 10.1186/s12943-024-02012-z -
Journal of Clinical and Experimental... Apr 2024Since bleaching gels can cause adverse effects on tooth enamel, it is important to evaluate new remineralizing agents on the market and their effects.
BACKGROUND
Since bleaching gels can cause adverse effects on tooth enamel, it is important to evaluate new remineralizing agents on the market and their effects.
MATERIAL AND METHODS
Seventy-five bovine enamel/dentin blocks (4x4x3mm) were randomly divided into six groups (n=10): Negative Control (NC) with no bleaching treatment or brushing; 10 CP (Carbamide Peroxide) (no brushing - Whiteness Perfect FGM); CT12 + 10 CP (Colgate Total® 12); ES + 10 CP (Elmex® Sensitive); BPC + 10 CP (Bianco® ProClinical); CMP + 10 CP (Colgate® Máxima Proteção Anticáries). The color was evaluated by reflectance spectrophotometry (∆E*ab, ∆E00, and ∆WID) at times T1 (baseline), T2 (24 hours after brushing), and T3 (24 hours after bleaching). Knoop microhardness (KHN) analysis were performed at T3. The enamel surface was qualitatively analyzed by Scanning Electron Microscopy (SEM). The data were analyzed using generalized linear models through descriptive and exploratory analyses, and a significance level of 5% was considered.
RESULTS
Significant differences were observed when the bleached groups were compared to the NC group for ∆E*ab, ∆E00, and ∆WID at time T3 (= <0.0001). However, the bleached groups presented no significant differences regarding studied times (> 0.05). KHN did not differ significantly among the six groups (=0.7585).
CONCLUSIONS
Toothpastes with tricalcium phosphate (β-TCP) do not intervene with the efficacy of bleaching treatment with 10% carbamide peroxide. Although a slight mineral deposition on enamel surface can be observed on SEM images, KHN was not significantly altered, and the polishing of the samples were maintained. Dental Bleaching, Carbamide Peroxide, Hydrogen Peroxide, Dental Enamel, Tricalcium Phosphate.
PubMed: 38725818
DOI: 10.4317/jced.61300 -
Genome Biology May 2024Preeclampsia, one of the most lethal pregnancy-related diseases, is associated with the disruption of uterine spiral artery remodeling during placentation. However, the...
BACKGROUND
Preeclampsia, one of the most lethal pregnancy-related diseases, is associated with the disruption of uterine spiral artery remodeling during placentation. However, the early molecular events leading to preeclampsia remain unknown.
RESULTS
By analyzing placentas from preeclampsia, non-preeclampsia, and twin pregnancies with selective intrauterine growth restriction, we show that the pathogenesis of preeclampsia is attributed to immature trophoblast and maldeveloped endothelial cells. Delayed epigenetic reprogramming during early extraembryonic tissue development leads to generation of excessive immature trophoblast cells. We find reduction of de novo DNA methylation in these trophoblast cells results in selective overexpression of maternally imprinted genes, including the endoretrovirus-derived gene PEG10 (paternally expressed gene 10). PEG10 forms virus-like particles, which are transferred from the trophoblast to the closely proximate endothelial cells. In normal pregnancy, only a low amount of PEG10 is transferred to maternal cells; however, in preeclampsia, excessive PEG10 disrupts maternal vascular development by inhibiting TGF-beta signaling.
CONCLUSIONS
Our study reveals the intricate epigenetic mechanisms that regulate trans-generational genetic conflict and ultimately ensure proper maternal-fetal interface formation.
Topics: Pre-Eclampsia; Pregnancy; Female; Humans; Trophoblasts; Vascular Remodeling; Placenta; DNA Methylation; Epigenesis, Genetic; Endothelial Cells; DNA-Binding Proteins; Genomic Imprinting; Transforming Growth Factor beta; Fetal Growth Retardation; Placentation; RNA-Binding Proteins; Apoptosis Regulatory Proteins
PubMed: 38715110
DOI: 10.1186/s13059-024-03265-z -
PloS One 2024Tularemia is a zoonotic disease caused by the facultative intracellular gram-negative bacterium Francisella tularensis. F. tularensis has a very low infection dose by...
Tularemia is a zoonotic disease caused by the facultative intracellular gram-negative bacterium Francisella tularensis. F. tularensis has a very low infection dose by the aerosol route which can result in an acute, and potentially lethal, infection in humans. Consequently, it is classified as a Category A bioterrorism agent by the US Centers for Disease Control (CDC) and is a pathogen of concern for the International Biodefence community. There are currently no licenced tularemia vaccines. In this study we report on the continued assessment of a tularemia subunit vaccine utilising β-glucan particles (GPs) as a vaccine delivery platform for immunogenic F. tularensis antigens. Using a Fischer 344 rat infection model, we demonstrate that a GP based vaccine comprising the F. tularensis lipopolysaccharide antigen together with the protein antigen FTT0814 provided partial protection of F344 rats against an aerosol challenge with a high virulence strain of F. tularensis, SCHU S4. Inclusion of imiquimod as an adjuvant failed to enhance protective efficacy. Moreover, the level of protection afforded was dependant on the challenge dose. Immunological characterisation of this vaccine demonstrated that it induced strong antibody immunoglobulin responses to both polysaccharide and protein antigens. Furthermore, we demonstrate that the FTT0814 component of the GP vaccine primed CD4+ and CD8+ T-cells from immunised F344 rats to express interferon-γ, and CD4+ cells to express interleukin-17, in an antigen specific manner. These data demonstrate the development potential of this tularemia subunit vaccine and builds on a body of work highlighting GPs as a promising vaccine platform for difficult to treat pathogens including those of concern to the bio-defence community.
Topics: Animals; Tularemia; Rats; Bacterial Vaccines; Francisella tularensis; Rats, Inbred F344; Vaccines, Subunit; Disease Models, Animal; Glucans; T-Lymphocytes; Female; Antigens, Bacterial
PubMed: 38713688
DOI: 10.1371/journal.pone.0294998 -
IScience May 2024HER2 heterogeneity is a challenge for molecular imaging or treating HER2-positive breast cancer (BC). EGFR is coexpressed in some tumors exhibiting HER2 heterogeneity....
HER2 heterogeneity is a challenge for molecular imaging or treating HER2-positive breast cancer (BC). EGFR is coexpressed in some tumors exhibiting HER2 heterogeneity. Bispecific radioimmunoconjugates (bsRICs) that bind HER2 and EGFR were constructed by linking trastuzumab Fab through polyethyleneglycol (PEG) to EGF. We established s.c. tumors in NOD-SCID mice that homogeneously or heterogeneously expressed HER2 and/or EGFR by the inoculation of HER2-positive/EGFR-negative SK-OV-3 cells, EGFR-positive/HER2-negative MDA-MB-468 cells or mixtures of these cells. [Cu]Cu-NOTA-trastuzumab Fab-PEG-EGF were compared to [Cu]Cu-NOTA-trastuzumab Fab or [Cu]Cu-NOTA-EGF for the PET imaging of HER2 and/or EGFR-positive tumors. [Cu]Cu-NOTA-trastuzumab Fab-PEG-EGF bsRICs imaged tumors expressing HER2 or EGFR or heterogeneously expressing these receptors, while monospecific agents only imaged HER2-or EGFR-positive tumors. Our results indicate that bsRICs labeled with Cu are able to exploit receptor heterogeneity for tumor imaging. PET may select patients for radioimmunotherapy with bsRICs complexed to the β-particle emitter, Lu or Auger electron-emitter, In in a theranostic approach.
PubMed: 38711454
DOI: 10.1016/j.isci.2024.109750