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Nutrients Oct 2020Cataracts or clouding of the lens is the leading cause of blindness in the world. Age and diabetes are major risk factors, and with an increasing aging and diabetic... (Review)
Review
Cataracts or clouding of the lens is the leading cause of blindness in the world. Age and diabetes are major risk factors, and with an increasing aging and diabetic population, the burden of cataracts will grow. Cataract surgery is an effective way to restore vision; however, alternatives to cataract surgery are required to reduce the looming cataract epidemic. Since it is well established that oxidative damage plays a major role in the etiology of cataracts, antioxidants have been promoted as therapies to delay and/or prevent cataracts. However, many antioxidant interventions including vitamin C have produced mixed results as anti-cataract therapies. Progress has been made towards our understanding of lens physiology and the mechanisms involved in the delivery and uptake of antioxidants to the lens which may guide future studies aimed at addressing some of the inconsistencies seen in previous animal and human studies. Of interest is the potential for vitamin C based supplements in delaying the onset of cataracts post vitrectomy which occurs in up to 80% of patients within two years. These targeted approaches are required to reduce the burden of cataract on hospitals and improve the quality of life of our aging and diabetic population.
Topics: Aging; Animals; Antioxidants; Ascorbic Acid; Cataract; Diabetes Complications; Dietary Supplements; Humans; Nutritional Physiological Phenomena; Oxidative Stress; Risk Factors; Vitrectomy; Vitreous Body
PubMed: 33066702
DOI: 10.3390/nu12103142 -
Blood Oct 2021Primary vitreoretinal lymphoma (PVRL) is a rare form of primary central nervous system (CNS) lymphoma (PCNSL) arising in the intraocular compartment without brain... (Review)
Review
Primary vitreoretinal lymphoma (PVRL) is a rare form of primary central nervous system (CNS) lymphoma (PCNSL) arising in the intraocular compartment without brain involvement. Despite its apparent indolent clinical course, PVRL can cause permanent vision loss and CNS relapse, the major cause of death in patients with PVRL. The pathophysiology of PVRL is unknown. As in PCNSL, the transformation of the tumor cells likely originates outside the CNS, before the cells migrate to the eye and proliferate within an immune-permissive microenvironment. PVRL exhibits a biased immunoglobulin repertoire, suggesting underlying antigen selection. The diagnosis remains challenging, requiring close coordination between ophthalmologists and cytologists. Because of their rarity and fragility in the vitreous, lymphoma cells cannot always be identified. Interleukin levels, molecular biology, and imaging are used in combination with clinical ophthalmological examination to support the diagnosis of PVRL. Multi-institutional prospective studies are urgently needed to validate the equivocal conclusions regarding treatments drawn from heterogeneous retrospective or small cohort studies. Intravitreal injection of methotrexate or rituximab or local radiotherapy is effective at clearing tumor cells within the eyes but does not prevent CNS relapse. Systemic treatment based on high-dose methotrexate chemotherapy, with or without local treatment, might reduce this risk. At relapse, intensive consolidation chemotherapy followed by stem cell transplantation can be considered. Single-agent ibrutinib, lenalidomide, and temozolomide treatments are effective in patients with relapsed PVRL and should be tested as first-line treatments. Therapeutic response assessment based on clinical examination is improved by measuring cytokine levels but still needs to be refined.
Topics: Animals; Disease Management; Humans; Retina; Retinal Neoplasms; Vitreous Body
PubMed: 34036310
DOI: 10.1182/blood.2020008235 -
Journal of Hematology & Oncology Sep 2022Primary central nervous system lymphoma (PCNSL) is a type of central nervous system restricted non-Hodgkin lymphoma, whose histopathological diagnosis is majorly large B... (Review)
Review
Primary central nervous system lymphoma (PCNSL) is a type of central nervous system restricted non-Hodgkin lymphoma, whose histopathological diagnosis is majorly large B cell lymphoma. To provide specific, evidence-based recommendations for medical professionals and to promote more standardized, effective and safe treatment for patients with PCNSL, a panel of experts from the Chinese Neurosurgical Society of the Chinese Medical Association and the Society of Hematological Malignancies of the Chinese Anti-Cancer Association jointly developed an evidence-based consensus. After comprehensively searching literature and conducting systematic reviews, two rounds of Delphi were conducted to reach consensus on the recommendations as follows: The histopathological specimens of PCNSL patients should be obtained as safely and comprehensively as possible by multimodal tomography-guided biopsy or minimally invasive surgery. Corticosteroids should be withdrawn from, or not be administered to, patients with suspected PCNSL before biopsy if the patient's status permits. MRI (enhanced and DWI) should be performed for diagnosing and evaluating PCNSL patients where whole-body PET-CT be used at necessary time points. Mini-mental status examination can be used to assess cognitive function in the clinical management. Newly diagnosed PCNSL patients should be treated with combined high-dose methotrexate-based regimen and can be treated with a rituximab-inclusive regimen at induction therapy. Autologous stem cell transplantation can be used as a consolidation therapy. Refractory or relapsed PCNSL patients can be treated with ibrutinib with or without high-dose chemotherapy as re-induction therapy. Stereotactic radiosurgery can be used for PCNSL patients with a limited recurrent lesion who were refractory to chemotherapy and have previously received whole-brain radiotherapy. Patients with suspected primary vitreoretinal lymphoma (PVRL) should be diagnosed by vitreous biopsy. PVRL or PCNSL patients with concurrent VRL can be treated with combined systemic and local therapy.
Topics: Antineoplastic Combined Chemotherapy Protocols; Central Nervous System; Central Nervous System Neoplasms; Consensus; Hematopoietic Stem Cell Transplantation; Humans; Lymphoma, Non-Hodgkin; Methotrexate; Positron Emission Tomography Computed Tomography; Retinal Neoplasms; Rituximab; Transplantation, Autologous; Vitreous Body
PubMed: 36176002
DOI: 10.1186/s13045-022-01356-7 -
Clinical Microbiology and Infection :... Nov 2019Adjunctive systemic antibiotic therapy for treatment of bacterial endophthalmitis is controversial but common practice due to the severity of the disease. In the absence... (Review)
Review
BACKGROUND
Adjunctive systemic antibiotic therapy for treatment of bacterial endophthalmitis is controversial but common practice due to the severity of the disease. In the absence of guidance documents, several antibiotic regimens are being used without applying evidence-based prescribing, leading to inappropriate treatment of this serious eye condition.
OBJECTIVES
To summarize available data on intravitreal penetration of systemically administered antibiotics and to discuss their usefulness from a microbiological and pharmacological point of view.
SOURCES
We performed a systematic PubMed search of studies investigating antibiotic concentrations in the vitreous after systemic administration in humans, and selected animal models.
CONTENT
The best-documented agents achieving therapeutic levels in the vitreous are meropenem, linezolid and moxifloxacin. Vancomycin, cefazoline, ceftriaxone, ceftazidime, imipenem and trimethoprim-sulfamethoxazole reach levels justifying their use in specific situations. Available data do not support the use of ciprofloxacin, levofloxacin, aminoglycosides, aminopenicillins, piperacillin, cefepime and clarithromycin. With very limited but available promising data, the use of daptomycin and rifampicin deserves further investigation.
IMPLICATIONS
The choice of the adjunctive systemic antibiotic agent-in situations where it is considered relevant for treatment-must to date be made on an individual basis, considering microbiological aspects as well as operative status and inflammation of the eye. This review gives a systematic overview of antibiotic options and provides guidance to the clinician striving for optimal systemic antibiotic treatment of bacterial endophthalmitis.
Topics: Administration, Intravenous; Animals; Anti-Bacterial Agents; Bacterial Infections; Disease Models, Animal; Endophthalmitis; Humans; Vitreous Body
PubMed: 30771529
DOI: 10.1016/j.cmi.2019.01.017 -
Indian Journal of Ophthalmology Nov 2023
Topics: Humans; Vitrectomy; Vacuum; Vitreous Body; Retrospective Studies
PubMed: 37870030
DOI: 10.4103/IJO.IJO_3388_22 -
International Journal of Molecular... Dec 2022Several common ocular diseases are leading causes of irreversible visual impairment. Over the last decade, various mainly untargeted metabolic studies have been... (Review)
Review
Several common ocular diseases are leading causes of irreversible visual impairment. Over the last decade, various mainly untargeted metabolic studies have been performed to show that metabolic dysfunction plays an important role in the pathogenesis of ocular diseases. A number of metabolites in plasma/serum, aqueous or vitreous humor, or in tears have been found to differ between patients and controls; among them are L-carnitine and acylcarnitines, which are essential for mitochondrial fatty acid oxidation. The metabolic profile of carnitines regarding a variety of diseases has attracted researchers' interest. In this review, we present and discuss recent advances that have been made in the identification of carnitines as potential metabolic biomarkers in common ocular diseases, such as age-related macular degeneration, diabetic retinopathy, retinopathy of prematurity, central retinal vein occlusion, primary open-angle glaucoma, rhegmatogenous retinal detachment, and dry eye syndrome.
Topics: Infant, Newborn; Humans; Ophthalmology; Glaucoma, Open-Angle; Carnitine; Vitreous Body; Biomarkers
PubMed: 36555822
DOI: 10.3390/ijms232416183 -
Translational Vision Science &... Sep 2022Vitreous substitutes are traditionally used to stabilize the retina after vitrectomy. In recent years, various approaches have been developed for using the vitreous... (Review)
Review
Vitreous substitutes are traditionally used to stabilize the retina after vitrectomy. In recent years, various approaches have been developed for using the vitreous substitute not only as a tamponade but also as a drug release system to tackle ocular diseases. This review provides an overview of the requirements for vitreous substitutes and discusses the current clinically applied as well as novel polymer-based vitreous substitutes as drug delivery systems, including their release mechanisms, efficiencies, challenges, and future perspectives.
Topics: Drug Liberation; Polymers; Retina; Vitrectomy; Vitreous Body
PubMed: 36125790
DOI: 10.1167/tvst.11.9.14 -
Molecular Vision 2020To investigate the relationship between inflammation in the vitreous and diabetic retinopathy.
PURPOSE
To investigate the relationship between inflammation in the vitreous and diabetic retinopathy.
METHODS
Vitreous samples from 21 patients with proliferative diabetic retinopathy (PDR), 21 patients with nonproliferative diabetic retinopathy (NPDR), and 21 nondiabetic patients with idiopathic epiretinal membranes (control) were studied. The interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), matrix metalloproteinase (MMP)-2, MMP-9, and adiponectin levels in the vitreous were detected in all samples with enzyme-linked immunosorbent assay (ELISA). Samples were stored at -80 °C until analyzed.
RESULTS
The TNF-α levels in the vitreous were not statistically significant between all groups (p>0.005). The mean IFN-γ levels were statistically significantly higher in patients with PDR (70.98 pg/ml) and patients with NPDR (46.61 pg/ml) than in nondiabetic patients (22.02 pg/ml). There was a difference in the IFN-γ levels in the vitreous between patients with PDR and patients with NPDR (p<0.005). The MMP-2 and MMP-9 concentrations in the vitreous were not different between all groups (p>0.05). There was a correlation between the IFN-γ and TNF-α levels. We investigated the statistically significantly decreased levels of adiponectin in the proliferative (p<0.05) and nonproliferative (p<0.05) diabetic eyes compared to the nondiabetic eyes.
CONCLUSIONS
Increased levels of IFN-γ and TNF-α in the vitreous were found in patients with diabetes compared to nondiabetic patients. Decreased levels of adiponectin in the vitreous were found in patients with diabetes compared to nondiabetic patients. The data support the hypothesis that inflammation is associated with diabetic retinopathy.
Topics: Adiponectin; Diabetic Retinopathy; Female; Humans; Inflammation; Interferon-gamma; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Middle Aged; Tumor Necrosis Factor-alpha; Vitreous Body
PubMed: 33209014
DOI: No ID Found -
Experimental Eye Research Dec 2020The purpose of this research is to study the intraocular occurrence of SARS-CoV-2. In postmortem examinations, aqueous humor and the vitreous samples were collected. All... (Review)
Review
The purpose of this research is to study the intraocular occurrence of SARS-CoV-2. In postmortem examinations, aqueous humor and the vitreous samples were collected. All individuals were previously positive in nasopharyngeal swabbing and cause of death was respiratory failure due to SARS-CoV-2 infection. Testing was done using quantitative RT-PCR. We included 16 aqueous humor and 16 vitreous samples for PCR testing. None of the results was positive for SARS-CoV-2. Human GAPDH genes to verify the presence of RNA was present in all aqueous humor samples (16/16, 100%) and 15/16 (93.8%) vitreous samples. In conclusion, this case series found no evidence of SARS-CoV-2 in the intraocular milieu.
Topics: Aqueous Humor; COVID-19; COVID-19 Testing; Humans; RNA, Viral; SARS-CoV-2; Vitreous Body
PubMed: 32991885
DOI: 10.1016/j.exer.2020.108273 -
Frontiers in Immunology 2020The diseases affecting the retina or uvea (iris, ciliary body, or choroid) generate changes in the biochemical or protein composition of ocular fluids/tissues due to... (Review)
Review
The diseases affecting the retina or uvea (iris, ciliary body, or choroid) generate changes in the biochemical or protein composition of ocular fluids/tissues due to disruption of blood-retinal barrier. Ocular infections and inflammations are sight-threatening diseases associated with various infectious and non-infectious etiologies. Several etiological entities cause uveitis, a complex intraocular inflammatory disease. These causes of uveitis differ in different populations due to geographical, racial, and socioeconomic variations. While clinical appearance is sufficiently diagnostic in many diseases, some of the uveitic entities manifest nonspecific or atypical clinical presentation. Identification of biomarkers in such diseases is an important aid in their diagnostic armamentarium. Different diseases and their different severity states release varying concentrations of proteins, which can serve as biomarkers. Proteomics is a high throughput technology and a powerful screening tool for serum biomarkers in various diseases that identifies proteins by mass spectrometry and helps to improve the understanding of pathogenesis of a disease. Proteins determine the biological state of a cell. Once identified as biomarkers, they serve as future diagnostic and pharmaceutical targets. With a potential to redirect the diagnosis of idiopathic uveitis, ocular proteomics provide a new insight into the pathophysiology and therapeutics of various ocular inflammatory diseases. Tears, aqueous and vitreous humor represent potential repositories for proteomic biomarkers discovery in uveitis. With an extensive proteomics work done on animal models of uveitis, various types of human uveitis are being subjected to proteome analysis for biomarker discovery in different ocular fluids (vitreous, aqueous, or tears).
Topics: Animals; Aqueous Humor; Biomarkers; Eye; Humans; Predictive Value of Tests; Prognosis; Proteins; Proteome; Proteomics; Tears; Uveitis; Vitreous Body
PubMed: 33343583
DOI: 10.3389/fimmu.2020.610428