-
Cell Death Discovery Jun 2024This study assesses the neuroprotective potential of CPP-P1, a conjugate of an anti-apoptotic peptain-1 (P1) and a cell-penetrating peptide (CPP) in in vitro, in vivo,...
This study assesses the neuroprotective potential of CPP-P1, a conjugate of an anti-apoptotic peptain-1 (P1) and a cell-penetrating peptide (CPP) in in vitro, in vivo, and ex vivo glaucoma models. Primary retinal ganglion cells (RGCs) were subjected to either neurotrophic factor (NF) deprivation for 48 h or endothelin-3 (ET-3) treatment for 24 h and received either CPP-P1 or vehicle. RGC survival was analyzed using a Live/Dead assay. Axotomized human retinal explants were treated with CPP-P1 or vehicle for seven days, stained with RGC marker RBPMS, and RGC survival was analyzed. Brown Norway (BN) rats with elevated intraocular pressure (IOP) received weekly intravitreal injections of CPP-P1 or vehicle for six weeks. RGC function was evaluated using a pattern electroretinogram (PERG). RGC and axonal damage were also assessed. RGCs from ocular hypertensive rats treated with CPP-P1 or vehicle for seven days were isolated for transcriptomic analysis. RGCs subjected to 48 h of NF deprivation were used for qPCR target confirmation. NF deprivation led to a significant loss of RGCs, which was markedly reduced by CPP-P1 treatment. CPP-P1 also decreased ET-3-mediated RGC death. In ex vivo human retinal explants, CPP-P1 decreased RGC loss. IOP elevation resulted in significant RGC loss in mid-peripheral and peripheral retinas compared to that in naive rats, which was significantly reduced by CPP-P1 treatment. PERG amplitude decline in IOP-elevated rats was mitigated by CPP-P1 treatment. Following IOP elevation in BN rats, the transcriptomic analysis showed over 6,000 differentially expressed genes in the CPP-P1 group compared to the vehicle-treated group. Upregulated pathways included CREB signaling and synaptogenesis. A significant increase in Creb1 mRNA and elevated phosphorylated Creb were observed in CPP-P1-treated RGCs. Our study showed that CPP-P1 is neuroprotective through CREB signaling enhancement in several settings that mimic glaucomatous conditions. The findings from this study are significant as they address the pressing need for the development of efficacious therapeutic strategies to maintain RGC viability and functionality associated with glaucoma.
PubMed: 38942762
DOI: 10.1038/s41420-024-02070-8 -
PAM-flexible Engineered FnCas9 variants for robust and ultra-precise genome editing and diagnostics.Nature Communications Jun 2024The clinical success of CRISPR therapies hinges on the safety and efficacy of Cas proteins. The Cas9 from Francisella novicida (FnCas9) is highly precise, with a...
The clinical success of CRISPR therapies hinges on the safety and efficacy of Cas proteins. The Cas9 from Francisella novicida (FnCas9) is highly precise, with a negligible affinity for mismatched substrates, but its low cellular targeting efficiency limits therapeutic use. Here, we rationally engineer the protein to develop enhanced FnCas9 (enFnCas9) variants and broaden their accessibility across human genomic sites by ~3.5-fold. The enFnCas9 proteins with single mismatch specificity expanded the target range of FnCas9-based CRISPR diagnostics to detect the pathogenic DNA signatures. They outperform Streptococcus pyogenes Cas9 (SpCas9) and its engineered derivatives in on-target editing efficiency, knock-in rates, and off-target specificity. enFnCas9 can be combined with extended gRNAs for robust base editing at sites which are inaccessible to PAM-constrained canonical base editors. Finally, we demonstrate an RPE65 mutation correction in a Leber congenital amaurosis 2 (LCA2) patient-specific iPSC line using enFnCas9 adenine base editor, highlighting its therapeutic utility.
Topics: Humans; Gene Editing; CRISPR-Associated Protein 9; CRISPR-Cas Systems; Francisella; Bacterial Proteins; Leber Congenital Amaurosis; Streptococcus pyogenes; HEK293 Cells; Mutation; RNA, Guide, CRISPR-Cas Systems; Protein Engineering; Genome, Human
PubMed: 38942756
DOI: 10.1038/s41467-024-49233-w -
Contact Lens & Anterior Eye : the... Jun 2024Rigid contact lenses have an important role in contact lens practice. The purpose of this work is to update earlier surveys by describing global trends in rigid lens...
PURPOSE
Rigid contact lenses have an important role in contact lens practice. The purpose of this work is to update earlier surveys by describing global trends in rigid lens fitting between 2000-2023.
METHOD
An annual contact lens prescribing survey was sent to eye care practitioners in up to 71 countries between 2000 and 2023. Data relating to 342,500 fits undertaken in 20 countries returning reliable longitudinal data were analysed in respect of rigid lens fitting, defined as the fitting of any design of a contact lens manufactured in a rigid material.
RESULTS
Overall, rigid lens prescribing increased slightly over time, from 14.2 % of lens fits in 2000 to 15.2 % in 2023 (p < 0.0001). However, post-hoc analysis shows that the change over time is best described as a decline between 2000 and 2012, followed by a steady increase subsequently. There were significant differences in rigid lens prescribing between countries (p < 0.0001). The difference between the percentage of males fitted with rigid lenses, as a proportion of all contact lenses (12.7 %), and females (12.0 %) is significant (p < 0.0001), although not clinically meaningful. Rigid lens wearers are older at fitting than soft lens wearers (38.7 vs 31.3 years, respectively) (p < 0.0001). Analysis of 5,994 rigid lens fits prescribed currently (2019-2023) were categorised as: corneal sphere - 30 %; scleral and corneo-scleral - 28 %; corneal myopia control/orthokeratology - 21 %; and corneal complex (including toric, multifocal and monovision) - 16 %.
CONCLUSION
There has been a slight increase in rigid lens fitting during the second decade of this century. This increase is apparently due to a 'repurposing' of rigid lenses, with the growth of scleral/corneo-scleral and myopia control/orthokeratology lens fits essentially replacing conventional spherical corneal lens fits.
PubMed: 38942659
DOI: 10.1016/j.clae.2024.102255 -
BMJ Paediatrics Open Jun 2024Raised intracranial pressure (ICP) contributes to approximately 20% of the admissions in the paediatric intensive care unit (PICU) in our setting. Timely identification... (Observational Study)
Observational Study
BACKGROUND
Raised intracranial pressure (ICP) contributes to approximately 20% of the admissions in the paediatric intensive care unit (PICU) in our setting. Timely identification and treatment of raised ICP is important to prevent brain herniation and death in such cases. The objective of this study was to examine the role of optic nerve sheath diameter (ONSD) in detecting clinically relevant raised ICP in children.
METHODS
A hospital-based observational analytical study in a PICU of a tertiary care institute in India on children aged 2-14 years. ONSD was measured in all children on three time points that is, day 1, day 2 and between day 4 and 7 of admission. ONSD values were compared between children with and without clinical signs of raised ICP.
RESULTS
Out of 137 paediatric patients recruited, 34 had signs of raised ICP. Mean ONSD on day 1 was higher in children with signs of raised ICP (4.99±0.57 vs 4.06±0.40; p<0.01). Mean ONSD on day 2 also was higher in raised ICP patients (4.94±0.55 vs 4.04±0.40; p<0.01). The third reading between days 4 and 7 of admission was less than the first 2 values but still higher in raised ICP patients (4.48±1.26 vs 3.99±0.57; p<0.001). The cut-off ONSD value for detecting raised ICP was 4.46 mm on the ROC curve with an area under curve 0.906 (95% CI 0.844 to 0.968), 85.3% sensitivity and 86.4% specificity. There was no difference in ONSD between the right and the left eyes at any time point irrespective of signs of raised ICP.
CONCLUSION
We found that measurement of ONSD by transorbital ultrasound was able to detect clinically relevant raised ICP with an excellent discriminatory performance at the cut-off value of 4.46 mm.
Topics: Humans; Child; Optic Nerve; Intracranial Hypertension; Child, Preschool; Female; Male; Adolescent; Intensive Care Units, Pediatric; India; Ultrasonography; Intracranial Pressure; ROC Curve; Sensitivity and Specificity
PubMed: 38942587
DOI: 10.1136/bmjpo-2023-002353 -
Gastrointestinal Endoscopy Jun 2024Computer-aided diagnosis (CADx) for optical diagnosis of colorectal polyps is thoroughly investigated. However, studies on human-artificial intelligence (AI) interaction...
BACKGROUND AND AIMS
Computer-aided diagnosis (CADx) for optical diagnosis of colorectal polyps is thoroughly investigated. However, studies on human-artificial intelligence (AI) interaction are lacking. Aim was to investigate endoscopists' trust in CADx by evaluating whether communicating a calibrated algorithm confidence improved trust.
METHODS
Endoscopists optically diagnosed 60 colorectal polyps. Initially, endoscopists diagnosed the polyps without CADx assistance (initial diagnosis). Immediately afterwards, the same polyp was again shown with CADx prediction; either only a prediction (benign or pre-malignant) or a prediction accompanied by a calibrated confidence score (0-100). A confidence score of 0 indicated a benign prediction, 100 a (pre-)malignant prediction. In half of the polyps CADx was mandatory, for the other half CADx was optional. After reviewing the CADx prediction, endoscopists made a final diagnosis. Histopathology was used as gold standard. Endoscopists' trust in CADx was measured as CADx prediction utilization; the willingness to follow CADx predictions when the endoscopists initially disagreed with the CADx prediction.
RESULTS
Twenty-three endoscopists participated. Presenting CADx predictions increased the endoscopists' diagnostic accuracy (69.3% initial vs 76.6% final diagnosis, p<0.001). The CADx prediction was utilized in 36.5% (n=183/501) disagreements. Adding a confidence score led to a lower CADx prediction utilization, except when the confidence score surpassed 60. A mandatory CADx decreased CADx prediction utilization compared to an optional CADx. Appropriate trust, utilizing correct or disregarding incorrect CADx predictions was 48.7% (n=244/501).
CONCLUSIONS
Appropriate trust was common and CADx prediction utilization was highest for the optional CADx without confidence scores. These results express the importance of a better understanding of human-AI interaction.
PubMed: 38942330
DOI: 10.1016/j.gie.2024.06.029 -
Acta Biomaterialia Jun 2024Applied to the epicardium in-vivo, regenerative cardiac patches support the ventricular wall, reduce wall stresses, encourage ventricular wall thickening, and improve...
Characterizing collagen scaffold compliance with native myocardial strains using an ex-vivo cardiac model: the physio-mechanical influence of scaffold architecture and attachment method.
Applied to the epicardium in-vivo, regenerative cardiac patches support the ventricular wall, reduce wall stresses, encourage ventricular wall thickening, and improve ventricular function. Scaffold engraftment, however, remains a challenge. After implantation, scaffolds are subject to the complex, time-varying, biomechanical environment of the myocardium. The mechanical capacity of engineered tissue to biomimetically deform and simultaneously support the damaged native tissue is crucial for its efficacy. To date, however, the biomechanical response of engineered tissue applied directly to live myocardium has not been characterized. In this paper, we utilize optical imaging of a Langendorff ex-vivo cardiac model to characterize the native deformation of the epicardium as well as that of attached engineered scaffolds. We utilize digital image correlation, linear strain, and 2D principal strain analysis to assess the mechanical compliance of acellular ice templated collagen scaffolds. Scaffolds had either aligned or isotropic porous architecture and were adhered directly to the live epicardial surface with either sutures or cyanoacrylate glue. We demonstrate that the biomechanical characteristics of native myocardial deformation on the epicardial surface can be accurately reproduced by an ex-vivo cardiac model. Furthermore, we identified that scaffolds with unidirectionally aligned pores adhered with suture fixation most accurately recapitulated the deformation of the native epicardium. Our study contributes a translational characterization methodology to assess the physio-mechanical performance of engineered cardiac tissue and adds to the growing body of evidence showing that anisotropic scaffold architecture improves the functional biomimetic capacity of engineered cardiac tissue. STATEMENT OF SIGNIFICANCE: Engineered cardiac tissue offers potential for myocardial repair, but engraftment remains a challenge. In-vivo, engineered scaffolds are subject to complex biomechanical stresses and the mechanical capacity of scaffolds to biomimetically deform is critical. To date, the biomechanical response of engineered scaffolds applied to live myocardium has not been characterized. In this paper, we utilize optical imaging of an ex-vivo cardiac model to characterize the deformation of the native epicardium and scaffolds attached directly to the heart. Comparing scaffold architecture and fixation method, we demonstrate that sutured scaffolds with anisotropic pores aligned with the native alignment of the superficial myocardium best recapitulate native deformation. Our study contributes a physio-mechanical characterization methodology for cardiac tissue engineering scaffolds.
PubMed: 38942187
DOI: 10.1016/j.actbio.2024.06.031 -
Biochemical Pharmacology Jun 2024This study introduces (S)-Opto-prop-2, a second-generation photoswitchable ligand designed for precise modulation of β-adrenoceptor (βAR). Synthesised by incorporating...
This study introduces (S)-Opto-prop-2, a second-generation photoswitchable ligand designed for precise modulation of β-adrenoceptor (βAR). Synthesised by incorporating an azobenzene moiety with propranolol, (S)-Opto-prop-2 exhibited a high PSS (photostationary state for cis isomer) percentage (∼90 %) and a favourable half-life (>10 days), facilitating diverse bioassay measurements. In vitro, the cis-isomer displayed substantially higher βAR binding affinity than the trans-isomer (1000-fold), making (S)-Opto-prop-2 one of the best photoswitchable GPCR (G protein-coupled receptor) ligands reported so far. Molecular docking of (S)-Opto-prop-2 in the X-ray structure of propranolol-bound βAR followed by site-directed mutagenesis studies, identified D113, N312 and F289 as crucial residues that contribute to ligand-receptor interactions at the molecular level. In vivo efficacy was assessed using a rabbit ocular hypertension model, revealing that the cis isomer mimicked propranolol's effects in reducing intraocular pressure, while the trans isomer was inactive. Dynamic optical modulation of βAR by (S)-Opto-prop-2 was demonstrated in two different cAMP bioassays and using live-cell confocal imaging, indicating reversible and dynamic control of βAR activity using the new photopharmacology tool. In conclusion, (S)-Opto-prop-2 emerges as a promising photoswitchable ligand for precise and reversible βAR modulation with light. The new tool shows superior cis-on binding affinity, one of the largest reported differences in affinity (1000-fold) between its two configurations, in vivo efficacy, and dynamic modulation. This study contributes valuable insights into the evolving field of photopharmacology, offering a potential avenue for targeted therapy in βAR-associated pathologies.
PubMed: 38942089
DOI: 10.1016/j.bcp.2024.116396 -
European Journal of Dentistry Jun 2024Sintering influences the optical properties of zirconia. This study examined the effect of altering sintering temperature and time of monochrome (Mo) and multilayer...
OBJECTIVES
Sintering influences the optical properties of zirconia. This study examined the effect of altering sintering temperature and time of monochrome (Mo) and multilayer (Mu) 5 mol% yttria-partially stabilized zirconia (5Y-PSZ) on color characteristics.
MATERIALS AND METHODS
Three hundred specimens (width × length × thickness = 10 × 20 × 2 mm) were prepared from Mo and Mu (with cervical [C], middle [M], and incisal [I] region) 5Y-PSZ and randomly sintered at decreasing (Td: 1,450°C), regular (Tr: 1,500°C), and increasing (TI: 1,550°C) sintering temperature, with extremely short (He: 10 minutes), ultrashort (Hu: 15 minutes), short (Hs: 30 minutes), and regular (Hr: 135 minutes) sintering time ( = 15/group). Color appearance ( ), translucency parameter (TP), contrast ratio (CR), opalescence parameter (OP), and color appearance difference (∆ ) were evaluated in the CIE L*a*b* system. Microstructures were evaluated by scanning electron microscope (SEM) and X-ray diffractometer (XRD).
STATISTICAL ANALYSIS
Analysis of variance (ANOVA) and Bonferroni comparisons were determined for significant differences ( < 0.05).
RESULTS
Significant differences in color parameters upon zirconia type, sintering temperature, and sintering time, and their interactions were indicated ( < 0.05). Increasing sintering temperature and extended sintered time resulted in larger grain, reduced tetragonal-to-monoclinic phase transformation, and significantly increased the TP and OP, but decreased the CR and ∆ ( < 0.05). Decreasing sintering temperature and time led to clinically unacceptable color appearance.
CONCLUSION
Mo was found to be more translucent than Mu. To achieve the most favorable optical properties, increasing sintering temperature and extending sintering time are recommended. Decreasing sintering temperature is not suggested. However, shortened sintering time is feasible, but it needs sintering with increasing sintering temperature to achieve a promising color appearance.
PubMed: 38942053
DOI: 10.1055/s-0044-1787700 -
Archives of Gerontology and Geriatrics Jun 2024To examine the associaiton between environmental measures and brain volumes and its potential mediators.
OBJECTIVES
To examine the associaiton between environmental measures and brain volumes and its potential mediators.
STUDY DESIGN
This was a prospective study.
METHODS
Our analysis included 34,454 participants (53.4% females) aged 40-73 years at baseline (between 2006 and 2010) from the UK Biobank. Brain volumes were measured using magnetic resonance imaging between 2014 and 2019.
RESULTS
Greater proximity to greenspace buffered at 1000 m at baseline was associated with larger volumes of total brain measured 8.8 years after baseline assessment (standardized β (95% CI) for each 10% increment in coverage: 0.013(0.005,0.020)), grey matter (0.013(0.006,0.020)), and white matter (0.011(0.004,0.017)) after adjustment for covariates and air pollution. The corresponding numbers for natural environment buffered at 1000 m were 0.010 (0.004,0.017), 0.009 (0.004,0.015), and 0.010 (0.004,0.016), respectively. Similar results were observed for greenspace and natural environment buffered at 300 m. The strongest mediator for the association between greenspace buffered at 1000 m and total brain volume was smoking (percentage (95% CI) of total variance explained: 7.9% (5.5-11.4%)) followed by mean sphered cell volume (3.3% (1.8-5.8%)), vitamin D (2.9% (1.6-5.1%)), and creatinine in blood (2.7% (1.6-4.7%)). Significant mediators combined explained 18.5% (13.2-25.3%) of the association with total brain volume and 32.9% (95% CI: 22.3-45.7%) of the association with grey matter volume. The percentage (95% CI) of the association between natural environment and total brain volume explained by significant mediators combined was 20.6% (14.7-28.1%)).
CONCLUSIONS
Higher coverage percentage of greenspace and environment may benefit brain health by promoting healthy lifestyle and improving biomarkers including vitamin D and red blood cell indices.
PubMed: 38941948
DOI: 10.1016/j.archger.2024.105546 -
Ecotoxicology and Environmental Safety Jun 20242-Ethylhexyl diphenyl phosphate (EHDPP) is a frequently utilized organophosphorus flame retardant (OPFR) and has been extensively detected in environmental media....
2-Ethylhexyl diphenyl phosphate (EHDPP) is a frequently utilized organophosphorus flame retardant (OPFR) and has been extensively detected in environmental media. Prolonged daily exposure to EHDPP has been linked to potential retinal damage, yet the adverse impacts on the retina are still generally underexplored. In this research, we explored oxidative stress, inflammation, and the activating mechanisms initiated by EHDPP in mouse retinal photoreceptor (661 W) cells following a 24 h exposure period. Our research demonstrated that EHDPP led to a decline in cell viability that was directly proportional to its concentration, with the median lethal concentration (LC50) being 88 µM. Furthermore, EHDPP was found to elevate intracellular and mitochondrial levels of reactive oxygen species (ROS), trigger apoptosis, induce cell cycle arrest at the G1 phase, and modulate the expression of both antioxidant enzymes (Nrf2, HO-1, and CAT) and pro-inflammatory mediators (TNF-α, IL-1β, and IL-6) within 661 W cells. These findings indicate that retinal damage triggered by EHDPP exposure could be mediated via the Nrf2/HO-1 signaling pathway in these cells. Collectively, our investigation revealed that oxidative stress induced by EHDPP is likely a critical factor in the cytotoxic response of 661 W cells, potentially leading to damage in retinal photoreceptor cells.
PubMed: 38941656
DOI: 10.1016/j.ecoenv.2024.116640