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International Journal of Legal Medicine Nov 2022The search for diatoms is the test that most of all may contribute to the forensic diagnosis of drowning. Diatoms can be extracted through different methods, which are...
The search for diatoms is the test that most of all may contribute to the forensic diagnosis of drowning. Diatoms can be extracted through different methods, which are all complex and long. In this preliminary study, we assessed human vitreous humor as an innovative substrate on which to research diatoms. Sampling and analyses were performed on 3 groups of 10 corpses each. The first one was composed of drowned victims. The second one of victims of traffic accidents with subsequent projection in water; based on the severe traumatic injuries reported at autopsy, we considered such victims as ideally assimilable to bodies immersed in water postmortem. The third group was composed of subjects who died for natural causes and without any relationship with water. The vitreous humor was centrifugated and cytocentrifuged and spotted on two different histological slides: one was left blank and the other one was assessed with hematoxylin and eosin staining. Microscopic observation successfully revealed diatoms in all cases of the first group; in the second group diatoms were not detected in 6 cases; in the third group, no diatoms at all were observed. Diatoms were always qualitatively and quantitatively consistent with those found in the corresponding viscera and waters, which had been investigated through classical acid digestion. Our analyses have demonstrated that the vitreous humor behaves in a completely similar way to the other viscera in cases of drowning. Although further investigations are necessary, vitreous humor has proved to be an innovative, suitable, and reliable substrate for the forensic research of diatoms.
Topics: Cadaver; Diatoms; Drowning; Eosine Yellowish-(YS); Forensic Pathology; Hematoxylin; Humans; Lung; Vitreous Body; Water
PubMed: 34999927
DOI: 10.1007/s00414-021-02759-w -
Ophthalmology. Retina Jan 2018
Topics: Cataract Extraction; Humans; Male; Middle Aged; Postoperative Complications; Tomography, Optical Coherence; Vitrectomy; Vitreous Body
PubMed: 31047308
DOI: 10.1016/j.oret.2017.09.005 -
Eye (London, England) May 2016Floaters are a common ocular condition which form as a consequence of aging changes in the vitreous. Although in most patients the symptoms are minimal, they can cause... (Review)
Review
Floaters are a common ocular condition which form as a consequence of aging changes in the vitreous. Although in most patients the symptoms are minimal, they can cause significant impairment in vision-related quality of life in a small population of patients. Recently there has been an increase in awareness of the visual disability caused by floaters, and the evidence-base for treatment of this condition using small-gauge vitrectomy has increased. In this review, we define the term 'floaters' as symptomatic vitreous opacities (SVO). We suggest a classification dependent on the presence or absence of posterior vitreous detachment and discuss their pathogenesis and natural history. We review their impact on patients' quality of life related to visual function. We review the psychological factors that may have a role in some patients who appear to be affected by SVO to the extent that they pursue all options including surgery with all its attendant risks. We summarise the available evidence-base of treatment options available for SVO with special emphasis on the safety and efficacy of vitrectomy for this condition.
Topics: Evidence-Based Medicine; Eye Diseases; Humans; Quality of Life; Vitrectomy; Vitreous Body
PubMed: 26939559
DOI: 10.1038/eye.2016.30 -
Survey of Ophthalmology 2015It is widely accepted that the origin of subretinal fluid in rhegmatogenous retinal detachment (RRD) is liquid vitreous and that posterior vitreous detachment (PVD) and... (Review)
Review
It is widely accepted that the origin of subretinal fluid in rhegmatogenous retinal detachment (RRD) is liquid vitreous and that posterior vitreous detachment (PVD) and associated retinal tears are caused by vitreoretinal traction from intra-ocular currents, contraction of collagen fibers, and gravity. These explanations, however, are incomplete. We present a new synthesis of experimental and clinical evidence, updating understanding of fundamental pathophysiological processes in RRD. Misdirected aqueous flow is shown to more convincingly explain the origin of subretinal fluid in clinical RRD, to be the most likely cause of acute PVD and retinal tear formation, and also to contribute to initial detachment of the retina at retinal tears. Misdirected aqueous flow in RRD is a pathophysiological process, rather than the "aqueous misdirection syndrome", and occurs without visible anterior chamber shallowing or acute glaucoma.
Topics: Aqueous Humor; Humans; Retinal Detachment; Retinal Perforations; Subretinal Fluid; Vitreous Body; Vitreous Detachment
PubMed: 25223495
DOI: 10.1016/j.survophthal.2014.07.002 -
Forensic Science International Apr 2021A more than 500% increase in the number of deaths involving methamphetamine occurred between 2016 and 2018 in Jeddah, Saudi Arabia. As such, this report employed a...
A more than 500% increase in the number of deaths involving methamphetamine occurred between 2016 and 2018 in Jeddah, Saudi Arabia. As such, this report employed a validated liquid chromatography tandem mass spectrometry method to quantify methamphetamine and its metabolites in bodily fluids from 47 postmortem cases in which methamphetamine was involved. The mean age of the deceased was 33 years old (median: 30, range: 16-63), and 94% were male. Methamphetamine was co-ingested with another drug in 32 of the cases (68%); however, the deaths were only due to the combined toxicity of methamphetamine and another drug in 15 of the cases (32%). Of note, 13 of these deaths (28% of all deaths) involved heroin. When methamphetamine was the sole cause of death (32% of the studied cases), the median concentrations of methamphetamine and amphetamine were 527 and 128 ng/mL. When methamphetamine was combined toxicity with another drug, the median concentrations of methamphetamine and amphetamine decreased to 161 and 53 ng/mL. When deaths were unrelated to methamphetamine, the median concentrations of methamphetamine and amphetamine were 130 and 44 ng/mL, respectively. The highest median methamphetamine concentration was found in urine (5281 ng/mL), followed by stomach contents (878 ng/mL), bile (762 ng/mL), vitreous humor (3 ng/mL), and blood (208 ng/mL). Almost 40% of the studied cases involved violence, 61% were accidental, 21% were suicides, 17% were homicides, and 2% were natural deaths. Methamphetamine is highly addictive. Increases in deaths have been seen in various countries. More awareness, education and treatment programs are required to reduce the likelihood of addiction, crimes, suicide, and other fatalities resulting from methamphetamine abuse.
Topics: Accidents; Adolescent; Adult; Age Distribution; Amphetamine-Related Disorders; Bile; Central Nervous System Stimulants; Female; Gastrointestinal Contents; Homicide; Humans; Male; Methamphetamine; Middle Aged; Saudi Arabia; Sex Distribution; Substance Abuse Detection; Suicide, Completed; Vitreous Body; Young Adult
PubMed: 33676238
DOI: 10.1016/j.forsciint.2021.110746 -
Investigative Ophthalmology & Visual... Mar 2023Age-related macular degeneration (AMD) is the leading cause of visual impairment worldwide. In this study, we aimed to investigate the vitreous humor metabolite profiles...
PURPOSE
Age-related macular degeneration (AMD) is the leading cause of visual impairment worldwide. In this study, we aimed to investigate the vitreous humor metabolite profiles of patients with intermediate AMD using untargeted metabolomics.
METHODS
We performed metabolomics using high-resolution liquid chromatography mass spectrometry on the vitreous humor of 31 patients with intermediate AMD and 30 controls who underwent vitrectomy for epiretinal membrane with or without cataract surgery. Univariate analyses after false discovery rate correction were performed to discriminate the metabolites and identify the significant metabolites of intermediate AMD. For biologic interpretation, enrichment and pathway analysis were conducted using MetaboAnalyst 5.0.
RESULTS
Of the 858 metabolites analyzed in the vitreous humor, 258 metabolites that distinguished patients with AMD from controls were identified (P values < 0.05). Ascorbic acid and uric acid levels increased in the AMD group (all P values < 0.05). The acyl carnitines, such as acetyl L-carnitine (1.37-fold), and fatty amides, such as anandamide (0.9-fold) and docosanamide (0.67-fold), were higher in patients with intermediate AMD. In contrast, nicotinamide (-0.55-fold), and succinic acid (-1.69-fold) were lower in patients with intermediate AMD. The metabolic pathway related oxidation of branched chain fatty acids and carnitine synthesis showed enrichment.
CONCLUSIONS
Multiple metabolites related to fatty amides and acyl carnitine were found to be increased in the vitreous humor of patients with intermediate AMD, whereas succinic acid and nicotinamide were reduced, suggesting that altered metabolites related to fatty amides and acyl carnitines and energy metabolism may be implicated in the etiology of AMD.
Topics: Humans; Amides; Carnitine; Macular Degeneration; Niacinamide; Succinates; Vitreous Body
PubMed: 36939720
DOI: 10.1167/iovs.64.3.28 -
Methods in Molecular Biology (Clifton,... 2019Metabolomics refers to the systematic identification and quantification of the small molecule metabolites (the metabolome) of a biological system in a given space (cell,...
Metabolomics refers to the systematic identification and quantification of the small molecule metabolites (the metabolome) of a biological system in a given space (cell, tissue, organ, biological fluid, or organism) and time. Global metabolic profiling provides broad range of coverage for most of the analytes present in any tissue. Human retina is metabolically highly active, and retinal vascular diseases such as age-related macular degeneration (AMD), diabetic retinopathy (DR), retinal vein occlusion (RVO), central retinal artery occlusion, and retinopathy of prematurity (ROP) are often associated with the disruptions in metabolic activities. A systematic study of total retinal metabolites from human diseased retina is a major challenge owing to the nonavailability of tissue specimens. Therefore, vitreous humor being very proximal to retina could be used as surrogate for retinal metabolomic analysis. As the extraction method adopted for such analysis determines the type of metabolites, two different types of solvent (methanol and chloroform)-based extraction methods could be used for retinal vascular patient samples (vitreous humor). Metabolites obtained from both the extraction methods are then subjected to LC-MS/MS for detection and identification.
Topics: Chemical Fractionation; Chloroform; Chromatography, High Pressure Liquid; Humans; Metabolomics; Methanol; Retina; Retinal Diseases; Solvents; Tandem Mass Spectrometry; Vitreous Body
PubMed: 31127565
DOI: 10.1007/978-1-4939-9488-5_24 -
Pharmaceutical Research Jan 2019Biomarkers provide a powerful and dynamic approach to improve our understanding of the mechanisms underlying ocular diseases with applications in diagnosis, disease... (Review)
Review
Biomarkers provide a powerful and dynamic approach to improve our understanding of the mechanisms underlying ocular diseases with applications in diagnosis, disease modulation or for predicting and monitoring of clinical response to treatment. Defined as measurable indicator of normal or pathological processes, biomarker evaluation has been used extensively in drug development within clinical settings to better comprehend effectiveness of treatment in ocular diseases. Biomarkers in the eye have the advantage of access to multiple ocular matrices via minimally invasive methods. Repeat sampling for biomarker assessment has enabled reproducible objective measures of disease process or biological responses to a drug treatment. This review describes the usage of biomarkers with respect to four commonly sampled ocular matrices in clinic: tears, conjunctiva, aqueous humor and vitreous. Issues that affect the evaluation of biomarkers are discussed along with opportunities to leverage biomarkers such that ultimately, they can be used for customized targeted therapy.
Topics: Animals; Aqueous Humor; Biomarkers; Conjunctiva; Eye Diseases; Humans; Tears; Vitreous Body
PubMed: 30673862
DOI: 10.1007/s11095-019-2569-8 -
Alzheimer's Research & Therapy Sep 2020Neurofilament light chain (NfL) is a promising biomarker of neurodegeneration in the cerebrospinal fluid and blood. This study investigated the presence of NfL in the...
BACKGROUND
Neurofilament light chain (NfL) is a promising biomarker of neurodegeneration in the cerebrospinal fluid and blood. This study investigated the presence of NfL in the vitreous humor and its associations with amyloid beta, tau, inflammatory cytokines and vascular proteins, apolipoprotein E (APOE) genotypes, Mini-Mental State Examination (MMSE) scores, systemic disease, and ophthalmic diseases.
METHODS
This is a single-site, prospective, cross-sectional cohort study. Undiluted vitreous fluid (0.5-1.0 mL) was aspirated during vitrectomy, and whole blood was drawn for APOE genotyping. NfL, amyloid beta (Aβ), total Tau (t-Tau), phosphorylated Tau (p-Tau181), inflammatory cytokines, chemokines, and vascular proteins in the vitreous were quantitatively measured by immunoassay. The main outcome measures were the detection of NfL levels in the vitreous humor and its associations with the aforementioned proteins. Linear regression was used to test the associations of NfL with other proteins, APOE genotypes, MMSE scores, and ophthalmic and systemic diseases after adjustment for age, sex, education level, and other eye diseases.
RESULTS
NfL was detected in all 77 vitreous samples. NfL was not found to be associated with ophthalmic conditions, APOE genotypes, MMSE scores, or systemic disease (p > 0.05). NfL levels were positively associated with increased vitreous levels of Aβ (p = 7.7 × 10), Aβ (p = 2.8 × 10), and t-tau (p = 5.5 × 10), but not with p-tau181 (p = 0.53). NfL also had significant associations with inflammatory cytokines such as interleukin-15 (IL-15, p = 5.3 × 10), IL-16 (p = 2.2 × 10), monocyte chemoattractant protein-1 (MCP1, p = 4.1 × 10), and vascular proteins such as vascular endothelial growth factor receptor-1 (VEGFR1, p = 2.9 × 10), Vegf-C (p = 8.6 × 10), vascular cell adhesion molecule-1 (VCAM-1, p = 5.0 × 10), Tie-2 (p = 6.3 × 10), and intracellular adhesion molecular-1 (ICAM-1, p = 1.6 × 10).
CONCLUSION
NfL is detectable in the vitreous humor of the eye and significantly associated with amyloid beta, t-tau, and select inflammatory and vascular proteins in the vitreous. Additionally, NfL was not associated with patients' clinical eye condition. Our results serve as a foundation for further investigation of NfL in the ocular fluids to inform us about the potential utility of its presence in the eye.
Topics: Alzheimer Disease; Amyloid beta-Peptides; Biomarkers; Cross-Sectional Studies; Humans; Intermediate Filaments; Neurofilament Proteins; Prospective Studies; Vascular Endothelial Growth Factor A; Vitreous Body; tau Proteins
PubMed: 32943089
DOI: 10.1186/s13195-020-00677-4 -
Vestnik Oftalmologii 2021This literature review provides modern information on the unique structure of the vitreous body, its functions, and its role in the pathogenesis of glaucoma, describes... (Review)
Review
This literature review provides modern information on the unique structure of the vitreous body, its functions, and its role in the pathogenesis of glaucoma, describes the features of the vitreous morphology and metabolism, notes its biomechanical and trophic functions, outlines its role in healthy hydrodynamics and hemodynamics of the eye, as well as in aqueous humor outflow. The review presents clinical observations on the association of pathological changes in the vitreous body with glaucoma development and examines the role of involutional changes in the vitreous in the pathogenesis of glaucoma. The article also discusses possible pathogenetic mechanisms of glaucoma development in terms of pathological changes in the vitreous.
Topics: Aqueous Humor; Glaucoma; Humans; Vitreous Body
PubMed: 34669344
DOI: 10.17116/oftalma2021137052323