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BMC Ophthalmology Apr 2024To explore the safety of Neodymium:Yttrium-aluminum-garnet (Nd:YAG) laser vitreolysis based on the histological examination of the retina and the alteration of vitreous...
BACKGROUND
To explore the safety of Neodymium:Yttrium-aluminum-garnet (Nd:YAG) laser vitreolysis based on the histological examination of the retina and the alteration of vitreous cytokines in the rabbits.
METHODS
Nine male New Zealand rabbits underwent Nd:YAG laser vitreolysis of 10 mJ x 500 pulses in the left eyes, while the right eyes were used as controls. Intraocular pressure, color fundus photography, and ultrasound B scan were measured before, as well as 1 day, 4 weeks, and 12 weeks after Nd:YAG laser vitreolysis. Three rabbits were euthanized 1 day, 4 weeks, and 12 weeks after treatment, respectively. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and hematoxylin-eosin (H&E) staining were used to look for pathological changes in the retina. An enzyme-linked immunosorbent assay (ELISA) was utilized to detect the expression of vascular endothelial growth factor (VEGF) and some inflammatory cytokines, including interferon inducible protein 10 (IP-10), monocyte chemoattractant protein 1 (MCP-1) and interlenkin 6 (IL-6) in the vitreous humor. The ascorbic acid (AsA) and total reactive antioxidant potential (TRAP) in the vitreous humor were also measured.
RESULTS
Following Nd:YAG laser vitreolysis, the levels of VEGF, IP-10, MCP-1, IL6, AsA, and TRAP in the vitreous humor did not change substantially (P > 0.05). There were no detectable pathological changes in the retinal tissues, and no apoptotic signal was found.
CONCLUSIONS
Rabbits tolerate Nd:YAG laser vitreolysis without observable impact on retinal tissue or the microenvironment of the vitreous.
Topics: Male; Rabbits; Animals; Vascular Endothelial Growth Factor A; Lasers, Solid-State; Chemokine CXCL10; Vitreous Body; Eye Diseases; Retina; Antioxidants; Ascorbic Acid; Laser Therapy
PubMed: 38627705
DOI: 10.1186/s12886-024-03406-9 -
Journal of Controlled Release :... Jun 2024Lipid-based drug formulations are promising systems for improving delivery of drugs to ocular tissues, such as retina. To develop lipid-based systems further, an...
Lipid-based drug formulations are promising systems for improving delivery of drugs to ocular tissues, such as retina. To develop lipid-based systems further, an improved understanding of their pharmacokinetics is required, but high-quality in vivo experiments require a large number of animals, raising ethical and economic questions. In order to expedite in vivo kinetic testing of lipid-based systems, we propose a barcode approach that is based on barcoding liposomes with non-endogenous lipids. We developed and evaluated a liquid-chromatography-mass spectrometry method to quantify many liposomes simultaneously in aqueous humor, vitreous, and neural retina at higher than ±20% precision and accuracy. Furthermore, we showed in vivo suitability of the method in pharmacokinetic evaluation of six different liposomes after their simultaneous injection into the rat vitreal cavity. We calculated pharmacokinetic parameters in vitreous and aqueous humor, quantified liposome concentrations in the retina, and quantitated retinal distribution of the liposomes in the rats. Compared to individual injections of the liposome formulations, the barcode-based study design enabled reduction of animal numbers from 72 to 12. We believe that the proposed approach is reliable and will reduce and refine ocular pharmacokinetic experiments with liposomes and other lipid-based systems.
Topics: Animals; Liposomes; Vitreous Body; Aqueous Humor; Lipids; Retina; Male; Rats; Eye; Mass Spectrometry; Chromatography, Liquid; Rats, Sprague-Dawley; Tissue Distribution
PubMed: 38615893
DOI: 10.1016/j.jconrel.2024.04.023 -
Forensic Toxicology Apr 2024Τhe aim of the present study was to investigate the use of vitreous humor as an alternative biological material in forensic toxicology for the determination of...
PURPOSE
Τhe aim of the present study was to investigate the use of vitreous humor as an alternative biological material in forensic toxicology for the determination of quetiapine, 7-hydroxy-quetiapine, and nor-quetiapine. The distribution of these substances in vitreous humor was studied by determining and correlating their concentrations in vitreous humor with the respective concentrations in blood.
METHODS
During this study, a method for the determination of these substances was developed, validated and applied to postmortem samples obtained from 16 relative forensic cases. The sample preparation procedure included the isolation of the analytes from vitreous humor and blood samples using solid-phase extraction, with Bond Elut LRC C18 columns followed by derivatization with BSTFA with 1% TMCS prior to GC/MS analysis.
RESULTS
The developed method is characterized by a dynamic range of 10.0-1000.0 ng/mL (R ≥ 0.991) for the three substances, with a limit of detection and quantification of 3.0 and 10.0 ng/mL, respectively. Accuracy and precision were below 8.09% and 8.99%, respectively, for both biological materials, while absolute recovery for the three substances was greater than 81%. According to the results, quetiapine, 7-hydroxy-quetiapine, and nor-quetiapine are easily distributed in vitreous humor.
CONCLUSION
The results of the study indicate the usefulness of vitreous humor in toxicological analysis for the determination of these substances, especially when the traditional biological materials are not available. The levels of quetiapine and its metabolites in vitreous humor as well as the vitreous humor to blood concentration ratios can provide important information for a more thorough toxicological investigation of forensic cases.
PubMed: 38615314
DOI: 10.1007/s11419-024-00687-z -
BMC Ophthalmology Apr 2024To describe a case of bilateral multifocal chorioretinitis as the only presentation of acute West Nile virus (WNV) infection in the absence of neurological involvement.
BACKGROUND
To describe a case of bilateral multifocal chorioretinitis as the only presentation of acute West Nile virus (WNV) infection in the absence of neurological involvement.
CASE PRESENTATION
A 78-year-old Italian woman was admitted to our emergency department because she noticed blurry vision in both eyes. She did not report fever, fatigue, or neurological symptoms in the last few days. Multimodal imaging showed the presence of bilateral hyperfluorescent lesions with a linear distribution, that corresponded to hypocyanescent spots on indocyanine green angiography. Antibody serology showed the presence of IgM antibodies, IgG antibodies, and ribonucleic acid (RNA) for WNV. Magnetic resonance imaging (MRI) of the brain ruled out central nervous system involvement. Three months later, the patient reported spontaneous resolution of her symptoms and remission of the chorioretinal infiltrates.
CONCLUSIONS
In endemic areas, it is important to think of acute WNV infection as an explanatory etiology in cases of multifocal chorioretinitis, even without neurological involvement.
Topics: Humans; Female; Aged; West Nile Fever; West Nile virus; Eye Infections, Viral; Chorioretinitis; Vitreous Body; Antibodies, Viral
PubMed: 38600458
DOI: 10.1186/s12886-024-03423-8 -
Asia-Pacific Journal of Ophthalmology... 2024
Topics: Humans; Carcinoma, Renal Cell; Endophthalmitis; Kidney Neoplasms; Vitreous Body; Diagnosis, Differential; Male; Eye Neoplasms; Middle Aged; Cytology
PubMed: 38583527
DOI: 10.1016/j.apjo.2024.100055 -
ABCA4 mediated traumatic proliferative vitreoretinopathy associated with PI3K/Akt signaling pathway.Heliyon Apr 2024Proliferative vitreoretinopathy (PVR) is the main cause of retinal detachment. However, the underlying mechanism of PVR is complex and has not yet been fully elucidated....
BACKGROUND
Proliferative vitreoretinopathy (PVR) is the main cause of retinal detachment. However, the underlying mechanism of PVR is complex and has not yet been fully elucidated. The PI3K/Akt/mTOR signaling pathway is involved in angiogenesis and plays an important role in cell proliferation and tumor formation. Therefore, our study was designed to investigate the potential biological mechanisms of alleviating ARPE-19 cell and traumatic PVR model involving PI3K/Akt signaling pathway by targeting ABCA4.
MATERIALS AND METHODS
ARPE-19 cell model was induced by ABCA4 overexpression vector and si-ABCA4, then the ABCA4 overexpression vector and si-ABCA4 were constructed, the plasmids were expanded for cell transfection and verification. In addition, OE-ABCA4, shRNA NC and si-ABCA4 were transfected into ARPE-19 cells. Cell viability was detected by CCK-8 assay, cell cycle was determined by flow cytometry. The expression level and location of ABCA4 were detected by immunofluorescence. Finally, rabbit traumatic PVR model was induced by surgery, the adenovirus was injected into the vitreous body respectively, and the fundus observation was performed by direct ophthalmoscope observation combined with fundus photography, and the retinal routine histopathology HE staining was performed. Analysis of P21, CDK4, Cyclin D1, BAX, BAD, and ABCA4 was used by quantitative RT-PCR and Western blot. Besides, the expression level of ABCA4, AKT, -AKT, PI3K, p-PI3K, P38, p-P38, JNK, -JNK, ERK, and -ERK was detected by Western blot.
RESULTS
All results indicated that the viability of cells with high expression of ABC4A increased, while the viability of cells with inhibition of ABC4A decreased, the number of cells with high ABC4A expression was significantly higher, and the migration level of cells was significantly reduced after ABC4A inhibition (P < 0.05). ABC4A could affect cell apoptosis by affecting G1/G2 phase. The cell proliferation level was significantly increased with high expression of ABC4A. High expression of ABC4A increased phosphorylation levels, including -AKT, -PIK3, and p-P38, while inhibition of ABC4A decreased the expression levels of these proteins (P < 0.05). Inhibition of ABC4A could significantly improve retinopathy, indicating that the proliferation ability of cells was restored after inhibition of ABC4A.
CONCLUSIONS
Our finding suggested that inhibition of ABC4A ameliorated the injury degree of traumatic PVR and performed the potential anti-PVR effect via inhibiting PI3K/Akt signaling pathway, while promoting cell proliferation in both rabbit and ARPE-19 cells PVR model. The study has a certain innovation by building a traumatic PVR model to explore whether the ABCA4 participates in the regulation of the PI3K/AKT signaling pathway and the pathological mechanism of PVR regulation. At the same time, ABCA4's participation in the regulation of PI3K/Akt signaling pathway can prevent and delay the occurrence and development of PVR, which has positive significance for improving the survival rate and quality of life of patients, and also provides an important basis for its therapeutic mechanism. Therefore, our study demonstrated a significant strategy for inhibiting traumatic PVR via targeting PI3K/Akt/ABCA4 pathway.
PubMed: 38560110
DOI: 10.1016/j.heliyon.2024.e27024 -
American Journal of Ophthalmology Case... Jun 2024To report a case of secondary Multiple Evanescent White Dot Syndrome in a patient with preexisting wet age-related macular degeneration.
PURPOSE
To report a case of secondary Multiple Evanescent White Dot Syndrome in a patient with preexisting wet age-related macular degeneration.
OBSERVATION
A 75-year-old male on treat and extend regimen for wet age-related macular degeneration (AMD) presented with a sudden loss of vision and saw central dark shadow in the right eye (RE) for a duration of 1 week. There was no significant history preceding the visual loss. Examination showed a visual acuity (VA) of counting fingers at 1 meter in the right eye and 20/25 in the left eye. Anterior segment examination was unremarkable with dilated fundus examination showing a clear vitreous, tortuous blood vessel, a hyperemic disc and fibrosis at the macula. The left eye (LE) examination was unremarkable. Optical Coherence Tomography (OCT) showed fibrosis due to the previous wet AMD and hyperreflective excrescences projecting from the retinal pigment epithelium (RPE) outside of the old area of wet AMD. Fundus Fluorescein Angiogram (FFA) showed hyperfluorescent spots in a wreath-like pattern increasing in intensity in the early phase and showing late staining towards the late phase while Indocyanine green angiography (ICGA) did not clearly delineate the lesions. Fundus autofluorescence (FAF) revealed hyper Autofluorescence (AF) at the posterior pole. Optical Coherence Tomography Angiography (OCTA) revealed a flow reduction in the choriocapillaris of the affected area. Basic blood investigations with Venereal Disease Research Laboratory (VDRL), syphilitic IgM and IgG antibodies, Quantiferon TB gold test, complete renal function tests and liver function tests were performed. All the blood investigations were within normal limits and the workup for syphilis and tuberculosis was negative. The patient was started on 1mg/kg body weight of oral prednisolone (after the non-response to low dose of oral steroids) with the diagnosis of secondary multiple evanescent white dot syndrome (MEWDS) secondary to wet AMD. The patient was followed up every weekly and the last visit showed improvement in visual acuity to 20/50 with resolution of lesions on FAF and OCT macula.
CONCLUSION AND IMPORTANCE
Secondary MEWDS is extremely rare and unique in terms of its presentation and its association with preexisting chorioretinal disease where there is damage to the choriocapillaris- Bruch's membrane-RPE complex. This case report highlights one such rare case scenario and how multimodal imaging helps in the diagnosis, management and follow-up of patients with secondary MEWDS.
PubMed: 38559365
DOI: 10.1016/j.ajoc.2024.102016 -
Investigative Ophthalmology & Visual... Mar 2024Symptomatic vitreous opacifications, so-called floaters, are difficult to objectively assess majorly limiting the possibility of in vitro studies. Forward light...
PURPOSE
Symptomatic vitreous opacifications, so-called floaters, are difficult to objectively assess majorly limiting the possibility of in vitro studies. Forward light scattering was found previously to be increased in eyes with symptomatic floaters. Using an objective setup to measure forward light scattering, we studied the effects of enzymatically digesting the components of the vitreous body on straylight to develop an in vitro model of vitreous opacifications.
METHODS
Fifty-seven porcine vitreous bodies were digested using hyaluronidase, collagenase, trypsin, and bromelain, as well as using a combination of hyaluronidase + collagenase and hyaluronidase + bromelain. A modified C-Quant setup was used to objectively assess forward light scattering.
RESULTS
Depletion of hyaluronic acid majorly increased vitreous straylight (mean increase 34.4 deg2/sr; P = 0.01), whereas primarily digesting the vitreous gel with collagenase or trypsin did not significantly affect straylight. When collagenase or bromelain is applied in hyaluronic acid depleted vitreous gels, the increase in forward light scattering is reversed partially.
CONCLUSIONS
The age-related loss of hyaluronic acid primarily drives the increase in vitreous gel straylight induced by conglomerates of collagen. This process can be reversed partially by digesting collagen. This in vitro model allows the objective quantification and statistical comparison of straylight burden caused by vitreous opacities and, thus, can serve as a first testing ground for pharmacological therapies, as demonstrated with bromelain.
Topics: Animals; Swine; Light; Bromelains; Hyaluronoglucosaminidase; Hyaluronic Acid; Trypsin; Aging; Collagen; Collagenases; Scattering, Radiation
PubMed: 38551585
DOI: 10.1167/iovs.65.3.36 -
Pharmaceutics Feb 2024The ranibizumab (RBZ) port delivery system (PDS) is a device designed to continuously deliver RBZ in the vitreous chamber for the treatment of neovascular age-related... (Review)
Review
Ranibizumab Port Delivery System in Neovascular Age-Related Macular Degeneration: Where Do We Stand? Overview of Pharmacokinetics, Clinical Results, and Future Directions.
The ranibizumab (RBZ) port delivery system (PDS) is a device designed to continuously deliver RBZ in the vitreous chamber for the treatment of neovascular age-related macular degeneration (nAMD). It is implanted during a surgical procedure and can provide sustained release of the medication for several months. This review, updated to January 2024, focuses on past clinical studies as well as current and forthcoming trials looking into a PDS with RBZ. In the phase 2 LADDER trial, the mean time to first refill of a PDS with RBZ 100 mg/mL was 15.8 months, with the pharmacokinetic (PK) profile showing a sustained concentration of RBZ in the blood and aqueous humor. More recently, a PDS with RBZ (100 mg/mL) refilled every 24 weeks was shown to be non-inferior to a monthly intravitreal injection (IVI) with RBZ (0.5 mg) over 40 and 92 weeks in the phase 3 ARCHWAY trial. The refill every 24 weeks allowed for a RBZ vitreous exposure within the concentration range of monthly intravitreal injections (IVIs), and the expected half-life (106 days) was comparable with the in vitro results. Nonetheless, vitreous hemorrhage and endophthalmitis were more common side effects in PDS patients. In conclusion, a PDS continuously delivering RBZ has a clinical effectiveness level comparable with IVI treatment. However, a greater frequency of unfavorable occurrences highlights the need for procedure optimization for a wider adoption. Ongoing trials and possible future approaches need to be addressed.
PubMed: 38543208
DOI: 10.3390/pharmaceutics16030314 -
Biomedicines Mar 2024Glaucoma is a multifactorial pathology involving the immune system. The subclinical immune response plays a homeostatic role in healthy situations, but in pathological...
Glaucoma is a multifactorial pathology involving the immune system. The subclinical immune response plays a homeostatic role in healthy situations, but in pathological situations, it produces imbalances. Optical coherence tomography detects immune cells in the vitreous as hyperreflective opacities and these are subsequently characterised by computational analysis. This study monitors the changes in immunity in the vitreous in two steroid-induced glaucoma (SIG) animal models created with drug delivery systems (microspheres loaded with dexamethasone and dexamethasone/fibronectin), comparing both sexes and healthy controls over six months. SIG eyes tended to present greater intensity and a higher number of vitreous opacities ( < 0.05), with dynamic fluctuations in the percentage of isolated cells (10 µm), non-activated cells (10-50 µm), activated cells (50-250 µm) and cell complexes (>250 µm). Both SIG models presented an anti-inflammatory profile, with non-activated cells being the largest population in this study. However, smaller opacities (isolated cells) seemed to be the first responder to noxa since they were the most rounded (recruitment), coinciding with peak intraocular pressure increase, and showed the highest mean Intensity (intracellular machinery), even in the contralateral eye, and a major change in orientation (motility). Studying the features of hyperreflective opacities in the vitreous using OCT could be a useful biomarker of glaucoma.
PubMed: 38540246
DOI: 10.3390/biomedicines12030633