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1.
iScience ; 27(6): 109875, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38774716

RESUMEN

The cornea and sclera are distinct adjacent tissues, yet their stromal cells originate from common neural crest cells (NCCs). Sclerocornea is a disease characterized by an indistinguishable boundary between the cornea and sclera. Previously, we identified a RAD21 mutation in a sclerocornea pedigree. Here, we investigated the impacts of RAD21 on NCC activities during eye development. RAD21 deficiency caused upregulation of PCDHGC3. Both RAD21 knockdown and PCDHGC3 upregulation disrupted the migration of NCCs. Transcriptome analysis indicated that WNT9B had 190.9-fold higher expression in scleral stroma than in corneal stroma. WNT9B was also significantly upregulated by both RAD21 knockdown and PCDHGC3 overexpression, and knock down of WNT9B rescued the differentiation and migration of NCCs with RAD21 deficiency. Consistently, overexpressing wnt9b in Xenopus tropicalis led to ocular developmental abnormalities. In summary, WNT9B is a determinant factor during NCC differentiation into corneal keratocytes or scleral stromal cells and is affected by RAD21 expression.

2.
Exp Eye Res ; 242: 109883, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38561106

RESUMEN

Corneal transplantation represents the primary therapeutic approach for managing corneal endothelial dysfunction, but corneal donors remain scarce. Anterior chamber cell injection emerges as a highly promising alternative strategy for corneal transplantation, with pluripotent stem cells (PSC) demonstrating considerable potential as an optimal cell source. Nevertheless, only a few studies have explored the differentiation of functional corneal endothelial-like cells originating from PSC. In this investigation, a chemical-defined protocol was successfully developed for the differentiation of functional corneal endothelial-like cells derived from human embryonic stem cells (hESC). The application of nicotinamide (NAM) exhibited a remarkable capability in suppressing the fibrotic phenotype, leading to the generation of more homogeneous and well-distinctive differentiated cells. Furthermore, NAM effectively suppressed the expression of genes implicated in endothelial cell migration and extracellular matrix synthesis. Notably, NAM also facilitated the upregulation of surface marker genes specific to functional corneal endothelial cells (CEC), including CD26 (-) CD44 (-∼+-) CD105 (-) CD133 (-) CD166 (+) CD200 (-). Moreover, in vitro functional assays were performed, revealing intact barrier properties and Na+/K+-ATP pump functionality in the differentiated cells treated with NAM. Consequently, our findings provide robust evidence supporting the capacity of NAM to enhance the differentiation of functional CEC originating from hESC, offering potential seed cells for therapeutic interventions of corneal endothelial dysfunction.


Asunto(s)
Diferenciación Celular , Endotelio Corneal , Células Madre Embrionarias Humanas , Niacinamida , Humanos , Diferenciación Celular/efectos de los fármacos , Niacinamida/farmacología , Endotelio Corneal/metabolismo , Endotelio Corneal/citología , Endotelio Corneal/efectos de los fármacos , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/metabolismo , Células Cultivadas , Complejo Vitamínico B/farmacología , Citometría de Flujo , Movimiento Celular/efectos de los fármacos , Antígenos CD/metabolismo , Antígenos CD/genética
3.
Exp Eye Res ; 241: 109853, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38453038

RESUMEN

High myopia is a risk factor for primary open angle glaucoma (POAG). The pathological mechanism of high myopia induced POAG occurrence is not fully understood. In this study, we successfully established the guinea pig model of ocular hypertension with high myopia, and demonstrated the susceptibility of high myopia for the occurrence of microbead-induced glaucoma compared with non-myopia group and the effect of YAP/TGF-ß signaling pathway in TM pathogenesis induced by high myopia. Moreover, we performed stretching treatment on primary trabecular meshwork (TM) cells to simulate the mechanical environment of high myopia. It was found that stretching treatment disrupted the cytoskeleton, decreased phagocytic function, enhanced ECM remodeling, and promoted cell apoptosis. The experiments of mechanics-induced human TM cell lines appeared the similar trend. Mechanically, the differential expressed genes of TM cells caused by stretch treatment enriched YAP/TGF-ß signaling pathway. To inhibit YAP/TGF-ß signaling pathway effectively reversed mechanics-induced TM damage. Together, this study enriches mechanistic insights of high myopia induced POAG susceptibility and provides a potential target for the prevention of POAG with high myopia.


Asunto(s)
Glaucoma de Ángulo Abierto , Hipertensión Ocular , Humanos , Animales , Cobayas , Factor de Crecimiento Transformador beta/metabolismo , Malla Trabecular/metabolismo , Glaucoma de Ángulo Abierto/prevención & control , Glaucoma de Ángulo Abierto/genética , Hipertensión Ocular/metabolismo , Factores de Riesgo , Células Cultivadas
4.
Sci Adv ; 10(1): eadj1741, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38170782

RESUMEN

Bacteria can swim upstream in a narrow tube and pose a clinical threat of urinary tract infection to patients implanted with catheters. Coatings and structured surfaces have been proposed to repel bacteria, but no such approach thoroughly addresses the contamination problem in catheters. Here, on the basis of the physical mechanism of upstream swimming, we propose a novel geometric design, optimized by an artificial intelligence model. Using Escherichia coli, we demonstrate the anti-infection mechanism in microfluidic experiments and evaluate the effectiveness of the design in three-dimensionally printed prototype catheters under clinical flow rates. Our catheter design shows that one to two orders of magnitude improved suppression of bacterial contamination at the upstream end, potentially prolonging the in-dwelling time for catheter use and reducing the overall risk of catheter-associated urinary tract infection.


Asunto(s)
Catéteres Urinarios , Infecciones Urinarias , Humanos , Catéteres Urinarios/microbiología , Inteligencia Artificial , Infecciones Urinarias/prevención & control , Infecciones Urinarias/microbiología , Bacterias , Escherichia coli , Hidrolasas
5.
Mol Pharm ; 21(2): 704-717, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38194618

RESUMEN

Monoclonal antibodies (mAbs) are active components of therapeutic formulations that interact with the water-vapor interface during manufacturing, storage, and administration. Surface adsorption has been demonstrated to mediate antibody aggregation, which leads to a loss of therapeutic efficacy. Controlling mAb adsorption at interfaces requires a deep understanding of the microscopic processes that lead to adsorption and identification of the protein regions that drive mAb surface activity. Here, we report all-atom molecular dynamics (MD) simulations of the adsorption behavior of a full IgG1-type antibody at the water/vapor interface. We demonstrate that small local changes in the protein structure play a crucial role in promoting adsorption. Also, interfacial adsorption triggers structural changes in the antibody, potentially contributing to the further enhancement of surface activity. Moreover, we identify key amino acid sequences that determine the adsorption of antibodies at the water-air interface and outline strategies to control the surface activity of these important therapeutic proteins.


Asunto(s)
Anticuerpos Monoclonales , Vapor , Anticuerpos Monoclonales/química , Adsorción , Agua/química , Composición de Medicamentos
6.
Mol Phys ; 121(19-20): e2236248, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38107421

RESUMEN

The aggregation of therapeutic proteins in solution has attracted significant interest, driving efforts to understand the relationship between microscopic structural changes and protein-protein interactions determining aggregation processes in solution. Additionally, there is substantial interest in being able to predict aggregation based on protein structure as part of molecular developability assessments. Molecular Dynamics provides theoretical tools to complement experimental studies and to interrogate and identify the microscopic mechanisms determining aggregation. Here we perform all-atom MD simulations to study the structure and inter-protein interaction of the Fab and Fc fragments of the monoclonal antibody (mAb) COE3. We unravel the role of ion-protein interactions in building the ionic double layer and determining effective inter-protein interaction. Further, we demonstrate, using various state-of-the-art force fields (charmm, gromos, amber, opls/aa), that the protein solvation, ionic structure and protein-protein interaction depend significantly on the force field parameters. We perform SANS and Static Light Scattering experiments to assess the accuracy of the different forcefields. Comparison of the simulated and experimental results reveal significant differences in the forcefields' performance, particularly in their ability to predict the protein size in solution and inter-protein interactions quantified through the second virial coefficients. In addition, the performance of the forcefields is correlated with the protein hydration structure.

7.
Biosens Bioelectron ; 242: 115725, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37837938

RESUMEN

Rapid and accurate on-site detection of aflatoxin B1 (AFB1) is of great significance for ensuring food safety. This work developed a dual mode aptasensor and a dual channel artificial neural network (ANN) intelligent sensor detection platform for simple and convenient quantitative detection of AFB1 in food. This sensor was prepared by encoding manganese ion (Mn2+) mediated surface concave niobium carbide MXene nanomaterials (Nb2C-MNs) using fluorescent group labeled aptamers (ssDNA-FAM). Mn2+-mediated Nb2C-MNs exhibited better peroxidase-like and fluorescence quenching properties. Moreover, ssDNA-FAM as a fluorescent probe for the sensor also significantly enhanced the enzyme activity of Nb2C-MNs. When AFB1 existed, ssDNA-FAM preferentially bonded to AFB1, resulting in fluorescence signal recovery and colorimetric signal weakening. Consequently, the multimodal biosensor could achieve fluorescence/colorimetric detection without the need for material and reagent replacement. In on-site detection, both ratio fluorescence and colorimetric signals could be collected using smartphones and analyzed and modeled on the developed ANN platform, achieving visual intelligent sensing. This multimodal biosensor had a detection line as low as 0.0950 ng/mL under optimal conditions, and also had the advantages of simple operation, fast and sensitive, and high specificity, which can meet the real-time on-site detection needs of AFB1 in remote areas.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Biosensibles/métodos , Niobio , Colorantes Fluorescentes , Aflatoxina B1/análisis , ADN de Cadena Simple , Límite de Detección
8.
iScience ; 26(10): 107982, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37810254

RESUMEN

Defects are prevalent in two-dimensional (2D) materials due to thermal equilibrium and processing kinetics. The presence of various defect types can affect material properties significantly. With the development of the advanced transmission electron microscopy (TEM), the property-related structures could be investigated in multiple dimensions. It produces TEM datasets containing a large amount of information. Traditional data analysis is influenced by the subjectivity of researchers, and manual analysis is inefficient and imprecise. Recent developments in deep learning provide robust methods for the quantitative identification of defects in 2D materials efficiently and precisely. Taking advantage of big data, it breaks the limitations of TEM as a local characterization tool, making TEM an intelligent macroscopic analysis method. In this review, the recent developments in the TEM data analysis of defects in 2D materials using deep learning technology are summarized. Initially, an in-depth examination of the distinctions between TEM and natural images is presented. Subsequently, a comprehensive exploration of TEM data analysis ensues, encompassing denoising, point defects, line defects, planar defects, quantitative analysis, and applications. Furthermore, an exhaustive assessment of the significant obstacles encountered in the accurate identification of distinct structures is also provided.

9.
Eye Vis (Lond) ; 10(1): 34, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37528478

RESUMEN

OBJECTIVE: Stem cell therapy is a promising strategy for the treatment of corneal endothelial dysfunction, and the need to find functional alternative seed cells of corneal endothelial cells (CECs) is urgent. Here, we determined the feasibility of using the retinal pigment epithelium (RPE) as an equivalent substitute for the treatment of corneal endothelial dysfunction. METHODS: RPE cells and CECs in situ were obtained from healthy New Zealand male rabbits, and the similarities and differences between them were analyzed by electron microscopy, immunofluorescent staining, and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Rabbit primary RPE cells and CECs were isolated and cultivated ex vivo, and Na+/K+-ATPase activity and cellular permeability were detected at passage 2. The injection of cultivated rabbit primary RPE cells, CECs and human embryonic stem cell (hESC)-derived RPE cells was performed on rabbits with corneal endothelial dysfunction. Then, the therapeutic effects were evaluated by corneal transparency, central corneal thickness, enzyme linked immunosorbent assay (ELISA), qRT-PCR and immunofluorescent staining. RESULTS: The rabbit RPE cells were similar in form to CECs in situ and ex vivo, showing a larger regular hexagonal shape and a lower cell density, with numerous tightly formed cell junctions and hemidesmosomes. Moreover, RPE cells presented a stronger barrier and ionic pumping capacity than CECs. When intracamerally injected into the rabbits, the transplanted primary RPE cells could dissolve corneal edema and decrease corneal thickness, with effects similar to those of CECs. In addition, the transplantation of hESC-derived RPE cells exhibited a similar therapeutic effect and restored corneal transparency and thickness within seven days. qRT-PCR results showed that the expressions of CEC markers, like CD200 and S100A4, increased, and the RPE markers OTX2, BEST1 and MITF significantly decreased in the transplanted RPE cells. Furthermore, we have demonstrated that rabbits transplanted with hESC-derived RPE cells maintained normal corneal thickness and exhibited slight pigmentation in the central cornea one month after surgery. Immunostaining results showed that the HuNu-positive transplanted cells survived and expressed ZO1, ATP1A1 and MITF. CONCLUSION: RPE cells and CECs showed high structural and functional similarities in barrier and pump characteristics. Intracameral injection of primary RPE cells and hESC-derived RPE cells can effectively restore rabbit corneal clarity and thickness and maintain normal corneal function. This study is the first to report the effectiveness of RPE cells for corneal endothelial dysfunction, suggesting the feasibility of hESC-derived RPE cells as an equivalent substitute for CECs.

10.
Entropy (Basel) ; 25(6)2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37372271

RESUMEN

As a pandemic emerges, information on epidemic prevention disseminates among the populace, and the propagation of that information interacts with the proliferation of the disease. Mass media serve a pivotal function in facilitating the dissemination of epidemic-related information. Investigating coupled information-epidemic dynamics, while accounting for the promotional effect of mass media in information dissemination, is of significant practical relevance. Nonetheless, in the extant research, scholars predominantly employ an assumption that mass media broadcast to all individuals equally within the network: this assumption overlooks the practical constraint imposed by the substantial social resources required to accomplish such comprehensive promotion. In response, this study introduces a coupled information-epidemic spreading model with mass media that can selectively target and disseminate information to a specific proportion of high-degree nodes. We employed a microscopic Markov chain methodology to scrutinize our model, and we examined the influence of the various model parameters on the dynamic process. The findings of this study reveal that mass media broadcasts directed towards high-degree nodes within the information spreading layer can substantially reduce the infection density of the epidemic, and raise the spreading threshold of the epidemic. Additionally, as the mass media broadcast proportion increases, the suppression effect on the disease becomes stronger. Moreover, with a constant broadcast proportion, the suppression effect of mass media promotion on epidemic spreading within the model is more pronounced in a multiplex network with a negative interlayer degree correlation, compared to scenarios with positive or absent interlayer degree correlation.

11.
Int J Ophthalmol ; 16(5): 743-747, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37206178

RESUMEN

AIM: To examine the change of iris volume measured by CASIA2 anterior segment optical coherence tomography (AS-OCT) in glaucoma patients with or without type 2 diabetes mellitus (T2DM) and explore if there is a correlation between hemoglobin A1c (HbA1c) level and iris volume. METHODS: In a cross-sectional study, 72 patients (115 eyes) were divided into two groups: primary open angle glaucoma (POAG) group (55 eyes) and primary angle-closure glaucoma (PACG) group (60 eyes). Patients in each group were separately classified into patients with or without T2DM. Iris volume and glycosylated HbA1c level were measured and analyzed. RESULTS: In the PACG group, diabetic patients' iris volume was significantly lower than those of non-diabetics (P=0.02), and there was a significant correlation between iris volume and HbA1c level in the PACG group (r=-0.26, P=0.04). However, diabetic POAG patients' iris volume was noticeably higher than those of non-diabetics (P=0.01), and there was a significant correlation between HbA1c level and iris volume (r=0.32, P=0.02). CONCLUSION: Diabetes mellitus impact iris volume size, as seen by increased iris volume in the POAG group and decreased iris volume in the PACG group. In addition, iris volume is significantly correlated with HbA1c level in glaucoma patients. These findings imply that T2DM may compromise iris ultrastructure in glaucoma patients.

12.
Mol Pharm ; 20(5): 2502-2512, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37012645

RESUMEN

Interfacial adsorption of monoclonal antibodies (mAbs) can cause structural deformation and induce undesired aggregation and precipitation. Nonionic surfactants are often added to reduce interfacial adsorption of mAbs which may occur during manufacturing, storage, and/or administration. As mAbs are commonly manufactured into ready-to-use syringes coated with silicone oil to improve lubrication, it is important to understand how an mAb, nonionic surfactant, and silicone oil interact at the oil/water interface. In this work, we have coated a polydimethylsiloxane (PDMS) nanofilm onto an optically flat silicon substrate to facilitate the measurements of adsorption of a model mAb, COE-3, and a commercial nonionic surfactant, polysorbate 80 (PS-80), at the siliconized PDMS/water interface using spectroscopic ellipsometry and neutron reflection. Compared to the uncoated SiO2 surface (mimicking glass), COE-3 adsorption to the PDMS surface was substantially reduced, and the adsorbed layer was characterized by the dense but thin inner layer of 16 Å and an outer diffuse layer of 20 Å, indicating structural deformation. When PS-80 was exposed to the pre-adsorbed COE-3 surface, it removed 60 wt % of COE-3 and formed a co-adsorbed layer with a similar total thickness of 36 Å. When PS-80 was injected first or as a mixture with COE-3, it completely prevented COE-3 adsorption. These findings reveal the hydrophobic nature of the PDMS surface and confirm the inhibitory role of the nonionic surfactant in preventing COE-3 adsorption at the PDMS/water interface.


Asunto(s)
Anticuerpos Monoclonales , Tensoactivos , Tensoactivos/química , Adsorción , Anticuerpos Monoclonales/química , Dióxido de Silicio , Aceites de Silicona/química , Polisorbatos/química , Dimetilpolisiloxanos
13.
Exp Eye Res ; 231: 109464, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37015319

RESUMEN

Corneal endothelium is mostly sensitive to oxidative pressure and mitochondrial dysfunction. However, the oxidative-antioxidant mechanism of corneal endothelial cells (CECs) remains partially defined. Silent information regulator 1 (SIRT1) is a well-studied therapeutic target of oxidative damage. This study aimed to determine the SIRT1 expression in ultraviolet A (UVA)-induced corneal endothelial damage and explore potential drugs to repair corneal endothelial oxidative injury. In this study, we showed that CECs exhibited cellular apoptosis, reactive oxygen species (ROS) accumulation and decreased SIRT1 expression. In addition, UVA induced the imbalance of mitochondrial homeostasis and function, involving in mitochondrial membrane potential, mitochondrial fusion/fission and mitochondrial energy metabolism. SRT1720, the SIRT1 activator, effectively increased SIRT1 expression and attenuated UVA-induced oxidative damage in CECs. The therapeutic effects of SRT1720 for corneal endothelial oxidative damage were also verified in UVA-irradiated mice model. Our findings indicated that SIRT1 maintained the oxidant-antioxidant balance in corneal endothelium, suggesting a new promising therapeutic target for corneal endothelial dysfunction.


Asunto(s)
Antioxidantes , Células Endoteliales , Ratones , Animales , Antioxidantes/farmacología , Antioxidantes/metabolismo , Células Endoteliales/metabolismo , Sirtuina 1/metabolismo , Estrés Oxidativo , Apoptosis
14.
Handb Exp Pharmacol ; 281: 257-276, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36882600

RESUMEN

The corneal endothelium is the innermost monolayer of the cornea that maintains corneal transparency and thickness. However, adult human corneal endothelial cells (CECs) possess limited proliferative capacity, and injuries can only be repaired by migration and enlargement of resident cells. When corneal endothelial cell density is lower than the critical level (400-500 cells/mm2) due to disease or trauma, corneal endothelial dysfunction will occur and lead to corneal edema. Corneal transplantation remains the most effective clinical treatment therapy but is limited by the global shortage of healthy corneal donors. Recently, researchers have developed several alternative strategies for the treatment of corneal endothelial disease, including the transplantation of cultured human CECs and artificial corneal endothelial replacement. Early-stage results show that these strategies can effectively resolve corneal edema and restore corneal clarity and thickness, but the long-term efficacy and safety remain to be further validated. Induced pluripotent stem cells (iPSCs) represent an ideal cell source for the treatment and drug discovery of corneal endothelial diseases, which can avoid the ethical-related and immune-related problems of human embryonic stem cells (hESCs). At present, many approaches have been developed to induce the differentiation of corneal endothelial-like cells from human induced pluripotent stem cells (hiPSCs). Their safety and efficacy for the treatment of corneal endothelial dysfunction have been confirmed in rabbit and nonhuman primate animal models. Therefore, the iPSC-derived corneal endothelial cell model may provide a novel effective platform for basic and clinical research of disease modeling, drug screening, mechanistic investigation, and toxicology testing.


Asunto(s)
Edema Corneal , Células Madre Pluripotentes Inducidas , Adulto , Animales , Humanos , Conejos , Células Endoteliales , Endotelio Corneal , Córnea , Células Cultivadas
15.
Mol Pharm ; 20(3): 1643-1656, 2023 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-36795985

RESUMEN

Interfacial adsorption is a molecular process occurring during the production, purification, transport, and storage of antibodies, with a direct impact on their structural stability and subsequent implications on their bioactivities. While the average conformational orientation of an adsorbed protein can be readily determined, its associated structures are more complex to characterize. Neutron reflection has been used in this work to investigate the conformational orientations of the monoclonal antibody COE-3 and its Fab and Fc fragments at the oil/water and air/water interfaces. Rigid body rotation modeling was found to be suitable for globular and relatively rigid proteins such as the Fab and Fc fragments but less so for relatively flexible proteins such as full COE-3. Fab and Fc fragments adopted a 'flat-on' orientation at the air/water interface, minimizing the thickness of the protein layer, but they adopted a substantially tilted orientation at the oil/water interface with increased layer thickness. In contrast, COE-3 was found to adsorb in tilted orientations at both interfaces, with one fragment protruding into the solution. This work demonstrates that rigid-body modeling can provide additional insights into protein layers at various interfaces relevant to bioprocess engineering.


Asunto(s)
Anticuerpos Monoclonales , Neutrones , Anticuerpos Monoclonales/química , Conformación Molecular , Adsorción , Fragmentos Fc de Inmunoglobulinas
16.
Graefes Arch Clin Exp Ophthalmol ; 261(6): 1651-1658, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36627493

RESUMEN

PURPOSE: To evaluate the agreement between swept-source OCT (CASIA2) and UBM in primary angle-closure glaucoma. METHODS: Eighty eyes of 40 participants diagnosed with primary angle-closure glaucoma were examined. Parameters measured included angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), trabecular iris angle (TIA), lens vault (LV), anterior chamber depth (ACD), and anterior chamber width (ACW). Angle images of nasal, temporal, superior, and inferior were acquired by the anterior segment mode of CASIA2 and UBM. One-way analysis of variance and paired t-test were used for statistical analysis, and the agreement was analyzed by internal correlation coefficient (ICC) and Bland-Altman method. RESULTS: One-way ANOVA pairwise comparison showed that CASIA2 or UBM had the narrowest superior chamber angle and the widest temporal chamber angle in patients with primary angle-closure glaucoma. The paired t-test showed that inter-device AOD, TIA, ARA, and TISA of superior chamber angle had significant differences (p < 0.001). There was no significant difference in the measured values of LV, ACD, and ACW (p > 0.05). The agreement of all parameters is good through the Bland-Altman method comparison. ICC result showed moderate agreement in other angle parameters except for superior ARA500 (0.739). CONCLUSION: In the anterior chamber angle measurement process, we should pay more attention to the superior chamber angle covered by eyelids. Although the agreement is acceptable between CASIA2 and UBM, the measurements could not be considered interchangeable due to the tremendous statistical difference between the two devices.


Asunto(s)
Glaucoma de Ángulo Cerrado , Cristalino , Humanos , Tomografía de Coherencia Óptica/métodos , Glaucoma de Ángulo Cerrado/diagnóstico , Microscopía Acústica , Cámara Anterior/diagnóstico por imagen , Segmento Anterior del Ojo/diagnóstico por imagen , Iris/diagnóstico por imagen , Gonioscopía
17.
ACS Nano ; 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36608273

RESUMEN

The rational design of lipid nanoparticles (LNPs) for enhanced gene delivery remains challenging because of incomplete knowledge of their formulation-structure relationship that impacts their intracellular behavior and consequent function. Small-angle neutron scattering has been used in this work to investigate the structure of LNPs encapsulating plasmid DNA upon their acidification (from pH 7.4 to 4.0), as would be encountered during endocytosis. The results revealed the acidification-induced structure evolution (AISE) of the LNPs on different dimension scales, involving protonation of the ionizable lipid, volume expansion and redistribution of aqueous and lipid components. A similarity analysis using an LNP's structural feature space showed a strong positive correlation between function (measured by intracellular luciferase expression) and the extent of AISE, which was further enhanced by the fraction of unsaturated helper lipid. Our findings reveal molecular and nanoscale changes occurring during AISE that underpin the LNPs' formulation-nanostructure-function relationship, aiding the rational design of application-directed gene delivery vehicles.

18.
Small ; 19(3): e2204428, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36417574

RESUMEN

Recent developments in antimicrobial peptides (AMPs) have focused on the rational design of short sequences with less than 20 amino acids due to their relatively low synthesis costs and ease of correlation of the structure-function relationship. However, gaps remain in the understanding of how short cationic AMPs interact with the bacterial outer and inner membranes to affect their antimicrobial efficacy and dynamic killing. The membrane-lytic actions of two designed AMPs, G(IIKK)3 I-NH2 (G3 ) and G(IIKK)4 I-NH2 (G4 ), and previously-studied controls GLLDLLKLLLKAAG-NH2 (LDKA, biomimetic) and GIGAVLKVLTTGLPALISWIKRKR-NH2 (Melittin, natural) are examined. The mechanistic processes of membrane damage and the disruption strength of the four AMPs are characterized by molecular dynamics simulations and experimental measurements including neutron reflection and scattering. The results from the combined studies are characterized with distinctly different intramembrane nanoaggregates formed upon AMP-specific binding, reflecting clear influences of AMP sequence, charge and the chemistry of the inner and outer membranes. G3 and G4 display different nanoaggregation with the outer and inner membranes, and the smaller sizes and further extent of insertion of the intramembrane nanoaggregates into bacterial membranes correlate well with their greater antimicrobial efficacy and faster dynamic killing. This work demonstrates the crucial roles of intramembrane nanoaggregates in optimizing antimicrobial efficacy and dynamic killing.


Asunto(s)
Antiinfecciosos , Péptidos Antimicrobianos , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Antiinfecciosos/farmacología , Bacterias , Simulación de Dinámica Molecular
19.
J Colloid Interface Sci ; 630(Pt B): 911-923, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36368131

RESUMEN

HYPOTHESIS: Designed antimicrobial lipopeptides (ALPs) offer the attractive benefits of short peptide sequences and flexible tuning of amphiphilicity by altering the acyl chain length. These lipopeptides kill microbes by forming intriguing in-membrane nanostructures and causing the leakage of internal contents. However, how subtle differences in the molecular structures of the lipopeptides affect their antimicrobial efficacy and biocompatibility to host cells is still under-investigated. EXPERIMENTS: This work focuses on assessing changes in the acyl chain length of CH3(CH2)n-2CO-KKKIII-NH2 (n = 10, 12 and 14, K = lysine, I = isoleucine, denoted as CnKI3) on the antimicrobial potency and cytotoxicity by combining biological assays with physical measurements. Aggregation properties were characterized by changes in critical aggregation concentration (CAC) from surface tension measurements. Antimicrobial susceptibility tests, cytotoxic MTT assays, haemolytic tests, and dynamic bactericidal experiments were employed to reveal their bioactive potency toward different types of cells. To further investigate lipopeptides' underlying antimicrobial and cytotoxic mechanisms, lipid monolayer and lipid small unilamellar vesicle (SUV) models were established and biophysically characterized. FINDINGS: An increase in n led to the decrease in the CAC of CnKI3, showing a rising membrane-lytic power. Subsequent bioactive measurements revealed the optimal performance of C12KI3 from this series of lipopeptides. The selective membrane binding behaviour was well supported by neutron reflection data from charged lipid monolayer models, revealing membrane-supported nanostructures of ALPs. However, increased membrane-lytic actions in C14KI3 led to notably increased toxicity and reduced selectivity. On the other hand, C14KI3 can impose faster dynamic killing than natural lipopeptide polymyxin B, showing the distinct impact of the amphiphilic balance from the designed lipopeptide. In contrast, the distinctly weaker binding to zwitterionic membrane models (monolayers and SUVs) provided direct nanoscale structural evidence to the mildness of the designed ALPs on host cells. This work demonstrates the high selectivity and fast killing of rationally designed short ALPs to microbes via in-membrane nanostructuring.


Asunto(s)
Antiinfecciosos , Lipopéptidos , Lipopéptidos/farmacología , Lipopéptidos/química , Antibacterianos/farmacología , Antibacterianos/química , Tensión Superficial , Secuencia de Aminoácidos
20.
Front Plant Sci ; 13: 1028779, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36457523

RESUMEN

Three ecotypes of rapeseed, winter, spring, and semi-winter, have been formed to enable the plant to adapt to different geographic areas. Although several major loci had been found to contribute to the flowering divergence, the genomic footprints and associated dynamic plant architecture in the vegetative growth stage underlying the ecotype divergence remain largely unknown in rapeseed. Here, a set of 41 dynamic i-traits and 30 growth-related traits were obtained by high-throughput phenotyping of 171 diverse rapeseed accessions. Large phenotypic variation and high broad-sense heritability were observed for these i-traits across all developmental stages. Of these, 19 i-traits were identified to contribute to the divergence of three ecotypes using random forest model of machine learning approach, and could serve as biomarkers to predict the ecotype. Furthermore, we analyzed genomic variations of the population, QTL information of all dynamic i-traits, and genomic basis of the ecotype differentiation. It was found that 213, 237, and 184 QTLs responsible for the differentiated i-traits overlapped with the signals of ecotype divergence between winter and spring, winter and semi-winter, and spring and semi-winter, respectively. Of which, there were four common divergent regions between winter and spring/semi-winter and the strongest divergent regions between spring and semi-winter were found to overlap with the dynamic QTLs responsible for the differentiated i-traits at multiple growth stages. Our study provides important insights into the divergence of plant architecture in the vegetative growth stage among the three ecotypes, which was contributed to by the genetic differentiation, and might contribute to environmental adaption and yield improvement.

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