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Dry eye is a complicated ocular surface disease that causes discomfort, visual disturbance, and frequently observed ocular surface damage. Emerging hypotheses suggest probiotics may help relieve dry eye symptoms by modulating inflammation and oxidative stress. This study aimed to investigate the therapeutic effects of Streptococcus thermophilus iHA318 probiotics on dry eye using in vitro assays and an in vivo murine model of ultraviolet B (UVB) radiation-induced dry eye. In vitro analyses revealed that S. thermophilus iHA318® exhibited antioxidant activity and anti-inflammatory effects by inhibiting reactive oxygen species production and suppressing inflammatory cytokines. For the in vivo study, female ICR mice were assigned to normal control, UVB-induced dry eye, and UVB+iHA318 treatment groups. UVB exposure significantly decreased tear volume and tear film breakup time (TBUT) compared to normal controls. Supplementation with S. thermophilus iHA318® via oral gavage markedly improved tear production and TBUT on day 7 post-UVB exposure. Ocular surface photography demonstrated improved gradings of corneal opacity, smoothness, and lissamine green staining in the iHA318 group versus the UVB group. Topographical analysis further revealed improvement in the UVB-induced corneal irregularities by iHA318 treatment. Collectively, these results indicate that S. thermophilus iHA318 exerts a protective effect against dry eye symptoms by mitigating oxidative stress and inflammation, thereby preserving tear film stability and ocular surface integrity. This probiotic strain represents a promising therapeutic approach for managing dry eye syndrome.
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The escalating prevalence of metabolic syndrome poses a significant public health challenge, particularly among aging populations, with metabolic dysfunctions contributing to pro-inflammatory states. In this review, we delved into the less recognized association between hyperuricemia (HUA), a manifestation of metabolic syndrome and a primary risk factor for gout, and age-related macular degeneration (AMD), a sight-threatening ailment predominantly affecting the elderly. In recent years, inflammation, particularly its involvement in complement pathway dysregulation, has gained prominence in AMD pathophysiology. The contradictory role of uric acid (UA) in intercellular and intracellular environments was discussed, highlighting its antioxidant properties in plasma and its pro-oxidant effects intracellularly. Emerging evidence suggests a potential link between elevated serum uric acid levels and choroid neovascularization in AMD, providing insights into the role of HUA in retinal pathologies. Various pathways, including crystal-induced and non-crystal-induced mechanisms, were proposed to indicate the need for further research into the precise molecular interactions. The implication of HUA in AMD underscores its potential involvement in retinal pathologies, which entails interdisciplinary collaboration for a comprehensive understanding of its impact on retina and related clinical manifestations.
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Gota , Hiperuricemia , Degeneração Macular , Humanos , Hiperuricemia/complicações , Hiperuricemia/metabolismo , Degeneração Macular/etiologia , Degeneração Macular/metabolismo , Gota/metabolismo , Gota/etiologia , Ácido Úrico/metabolismo , Ácido Úrico/sangue , AnimaisRESUMO
The Klotho loss-of-function mutation is known to cause accelerated senescence in many organs, but its effects on the cornea have not been published. The present study aims to investigate the effects of the Klotho null mutation on cornea degeneration and to characterize the pathological features. Mouse corneas of Klotho homozygous, heterozygous, and wild-type mice at 8 weeks of age for both genders were subject to pathological and immunohistological examinations. The results show an irregular topography on the corneal surface with a Klotho null mutation. Histological examinations revealed a reduced corneal epithelial cell density, endothelial cell-shedding, and decreased cornea stromal layer thickness in the absence of the Klotho function. Furthermore, guttae formation and the desquamation of wing cells were significantly increased, which was comparable to the characteristics of Fuchs endothelial corneal dystrophy and bullous keratopathy. The mechanism analysis showed multi-fold abnormalities, including oxidative stress-induced cornea epithelium apoptosis and inflammation, extracellular matrix remodeling in the stroma, and a disruption of epithelial repair, presumably through the epithelial-mesenchymal transition. In conclusion, cornea degeneration was observed in the Klotho loss-of-function mutant mice. These pathological features support the use of Klotho mutant mice for investigating age-related cornea anomalies, including Fuchs endothelial corneal dystrophy, bullous keratopathy, and dry eye diseases.
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The Klotho null mutation is known to lead to accelerated aging in many organs, but its effects on tear secretion and lacrimal gland (LG) senescence have not been addressed. This study investigated whether the Klotho null mutation would lead to a dry eye status and the outcome of LG without Klotho function. The Klotho (-/-) mutant mice showed reduced LG size and tear volume on the 8th week, as compared to their littermates (+/+, +/-). Hematoxylin-Eosin and Masson's trichrome staining were performed to determine morphological changes and collagen deposition. Traits of LG aging, including acinar atrophy, thickened capsules, and more collagen depositions, were observed. Immunohistochemical detections for Klotho, α-SMA, MDA, 8-OHdG, vasoactive intestinal polypeptide (VIP), tyrosine hydroxylase (TH), MMP-2, MMP-9, and FGF-23 were performed and compared among the three genotypes (+/+, +/-, -/-) at 6 and 8 weeks of age for mechanism analyses. Unexpectedly, the Klotho protein was not detected in the LG of all the three genotypes, indicating indirect effects from the Klotho null mutation. Further analyses showed abundant MDA and 8-OHdG detected in the Klotho (-/-) LG on the 8th week, indicating elevated oxidative stress. In addition, both sympathetic and parasympathetic neural transducing activities, as represented by TH and VIP expression, respectively, and α-SMA were increased in LGs with Klotho mutations. Furthermore, MMP-2 and MMP-9 expression were elevated, with FGF-23 expression being decreased on the 8th week in the Klotho (-/-) LG. In conclusion, characteristics of age-related LG degeneration were found in the Klotho null mutant mice. These traits support the use of Klotho mutant mice as a model of age-related dry eye disease.
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Cataracts, a prevalent age-related eye condition, pose a significant global health concern, with rising rates due to an aging population and increased digital device usage. In Taiwan, cataract prevalence is particularly high, reaching up to 90% among individuals aged 70 and above. The lens of the eye absorbs short-wave light, which can lead to oxidative stress in lens epithelial cells and contribute to cataract formation. Exposure to ultraviolet (UV) light further exacerbates the risk of cataracts by generating reactive oxygen species. Heat-shock proteins (HSPs), involved in protein maintenance and repair, have been linked to cataract development. Cordyceps cicadae (C. cicadae), a traditional Chinese medicine, has a long history of use and is known for its pharmacological effects. N6-(2-hydroxyethyl) adenosine (HEA), a bioactive compound found in C. cicadae, exhibits anti-inflammatory, immunomodulatory, and neuroprotective properties. Previous studies have shown that C. cicadae mycelial extracts improve dry eye disease and reduce intraocular pressure in animal models. Additionally, C. cicadae possesses antioxidant properties, which are beneficial for combating cataract formation. In this study, we aim to evaluate the preventive efficacy of C. cicadae mycelial extracts in UV-induced cataract development. By investigating the ameliorative effects of C. cicadae on eye diseases and its potential role in ocular health improvement, we hope to uncover new options for cataract prevention and provide insights into the mechanisms of action. The findings of this research could provide a novel approach for nutritional supplements targeting cataract prevention, offering potential benefits in the field of ocular health.
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Catarata , Cordyceps , Camundongos , Animais , Antioxidantes/farmacologia , Estresse Oxidativo , Adenosina , Catarata/etiologia , Catarata/prevenção & controleRESUMO
Purpose: Current ocular surface diagnostic methods may not totally meet and implement the clinical demands for early and precise treatments. The tear ferning (TF) test has been known as a quick, simple, and inexpensive procedure. This study aimed to validate the TF test as an alternative method for early determination of photokeratitis status. Methods: The tear sample was collected from the UVB-induced photokeratitis eyes and processed for TF formation. The TF patterns were graded by both the Masmali and a Sophie-Kevin (SK) grading criteria, a new set of criteria modified from the Masmali grading, for differential diagnoses. In addition, the TF test results were correlated with three clinical ocular surface indicators, including tear volume (TV), tear film break-up time (TBUT), and cornea staining, to evaluate the diagnostic capacity. Results: Differential diagnosis between the normal and the photokeratitis status was achieved by the TF test. The SK grading reflected earlier photokeratitis status than the Masmali grading criteria. The TF results were strongly correlated with the three clinical ocular surface indicators, particularly for the TBUT and cornea staining. Conclusions: The TF test was proven to have a capacity to distinguish photokeratitis from the normal status at an early stage by using the SK grading criteria. It is therefore potentially useful for photokeratitis diagnosis in the clinical settings. Translational Relevance: The TF test may fulfill the demands of precise and early diagnosis to facilitate in time the intervention for photokeratitis.
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Olho , Ceratite , Animais , Camundongos , Ceratite/diagnóstico , LágrimasRESUMO
Klotho is known for its age-suppressing function and has been implicated in sarcopenia pathology. It has recently been proposed that the adenosine A2B receptor plays a crucial role in skeletal muscle energy expenditure. However, the association between Klotho and A2B remains elusive. In this study, Klotho knockout mice, aged 10 weeks, and wild-type mice, aged 10 and 64 weeks, were used for comparison in indicators of sarcopenia (n = 6 for each group). PCR was performed to confirm the mice genotypes. Skeletal muscle sections were analyzed using hematoxylin and eosin staining as well as immunohistochemistry staining. The skeletal muscle cross-sectional area was significantly reduced in Klotho knockout mice and wild-type mice, aged 64 weeks, when compared with wild-type mice, aged 10 weeks, with a decreased percentage of type IIa and IIb myofibers. Likely impaired regenerative capacity, as reflected by the reduction of paired box 7 (Pax7)- and myogenic differentiation protein 1 (MyoD)-positive cells, was also observed in Klotho knockout mice and aged wild-type mice. 8-Hydroxy-2-deoxyguanosine expression was enhanced with Klotho knockout and aging, indicating higher oxidative stress. Adenosine A2B signaling was impaired, with a lower expression of the A2B receptor and the cAMP-response element binding protein in Klotho knockout and aged mice. The present study provides the novel finding that sarcopenia involves adenosine signaling under the influence of Klotho knockout.
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Receptor A2B de Adenosina , Sarcopenia , Camundongos , Animais , Receptor A2B de Adenosina/genética , Receptor A2B de Adenosina/metabolismo , Glucuronidase/metabolismo , Mutação com Perda de Função , Sarcopenia/genética , Sarcopenia/metabolismo , Sarcopenia/patologia , Músculo Esquelético/metabolismo , Camundongos KnockoutRESUMO
Dry eye disease (DED), a multifactorial inflammatory ocular surface disorder, affects up to 50% of individuals over 50 years old worldwide and is one of the most common reasons for seeking ophthalmologic care. Generally, topical eye drops or oral drugs are administered to treat DED; however, the use of preservatives in eye drops or the adverse effects of oral drugs are disadvantageous for long-term therapy. Cordyceps cicadae, a traditional Chinese medicinal fungus, possesses anti-inflammatory effects without evident toxicity and is obtainable at low price. Our previous study demonstrated that C. cicadae mycelium effectively ameliorates dry eye symptoms in the benzalkonium chloride (BAC)-induced mouse dry eye model by increasing tear volume and tear film breakup time (TBUT). However, the effects of C. cicadae mycelium for human dry eye amelioration remains unknown. Thus, the present study investigated the mitigation of dry eye conditions and related discomforts through oral supplementation of fermented C. cicadae mycelium. A total of 70 healthy individuals were recruited and randomly allocated to receive a daily oral dose of 1,050 mg preparation in sachet containing either freeze-dried C. cicadae mycelium powder with 0.3 mg of adenosine and 1.5 mg of HEA per gram or placebo for 90 days. The participants were subjected to anthropometric measurements, dry eye questionnaires (DEQ), Schirmer's tests, intraocular pressure (IOP) measurements, tear film breakup time (TBUT) tests, tear osmolality measurements, and tear electrolyte analysis prior to and right after completion of the study. The results showed a significantly increased TBUT as well as a significant decrease in tear osmolarity, in parallel with the decrease of tear electrolytes, especially Na+ and Cl ions. Although significant increase of tear volume was not observed, the increased TBUT suggests mitigation of dry eye through improvement of tear quality. Therefore, C. cicadae mycelium supplementation may be used for dry eye alleviation as a novel therapeutic intervention.
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Cordyceps , Síndromes do Olho Seco , Humanos , Animais , Camundongos , Pessoa de Meia-Idade , Projetos Piloto , Síndromes do Olho Seco/tratamento farmacológico , Síndromes do Olho Seco/diagnóstico , Soluções Oftálmicas/uso terapêutico , Micélio , Suplementos NutricionaisRESUMO
Purpose: Metabolic disorders have been implicated in ocular diseases, such as age-related macular degeneration (AMD) and diabetic retinopathy (DR). Recently, hyperuricemia (HUA) has been proposed as another risk factor for AMD, although no cause-and-effect experimental data have been published. In this study, we investigated whether HUA would initiate AMD or related retinal damages in hyperuricemic mice. Methods: HUA was induced in male ICR mice by dietary supplements of uric acid and oxonic acid potassium salt, with or without treatments by allopurinol or benzbromarone for various durations. Serum uric acid and angiotensin II concentrations were measured by enzyme-linked immunosorbent assay (ELISA) at regular intervals. The retinal damages were assessed by hematoxylin and eosin staining, immunostaining, and TUNEL assay. The cause-and-effect of HUA was compared among the study groups. Results: The results showed that the total thickness of photoreceptor inner and outer segments, as well as the thickness of the photoreceptor outer segment alone, were reduced under HUA. Furthermore, HUA elevated serum angiotensin II, which indicated activation of the renin-angiotensin system (RAS), leading to higher matrix metalloproteinase-2 (MMP-2) expression, and glial activation in the ganglion cell layer. HUA also led to the reduction of retinal pigment epithelium gap junction protein connexin-43 and apoptosis. Uric acid lowering agents, allopurinol or benzbromarone, were effective in ameliorating the impairments. Conclusions: HUA may pose as a causative factor of retinal injuries. The reduction of serum uric acid may reduce the detrimental effects caused by HUA.
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Hiperuricemia , Degeneração Macular , Alopurinol/farmacologia , Angiotensina II , Animais , Benzobromarona/farmacologia , Hiperuricemia/tratamento farmacológico , Degeneração Macular/complicações , Masculino , Metaloproteinase 2 da Matriz , Camundongos , Camundongos Endogâmicos ICR , Ácido ÚricoRESUMO
Objective:Cordyceps cicadae, a medicinal fungus, is assessed as having many functions: anti-cancer, anti-fatigue, anti-aging, immune-boosting, renal and liver protection. Since the industrial production of C. cicadae mycelium consistently manufactures bioactive compounds superior to wild fruiting bodies, there is a need to confirm the toxicity of liquid fermented C. cicadae mycelium. Studies showed the toxicity evaluation of C. cicadae mycelium in animal models, but safety reports in clinical studies are scarce. As such, a safety assessment of oral N6-(2-hydroxyethyl) adenosine (HEA-enriched) C. cicadae mycelium in humans is provided here.Method: After 49 participants ingested granules of 1.05 g of freeze-dried C. cicadae mycelium once a day for 3 months, their blood samples were collected at the beginning and end of the experiment for analysis.Results: There were no significant differences between the initial and final measurements in renal and liver function. Also, there was no influence on blood electrolytes as well as blood lipid levels. In clinical observation, there were also no side effects or adverse feelings mentioned by participants.Conclusion: These results suggested that HEA-enriched C. cicadae mycelium produced by liquid fermentation is safe and can be developed as a functional health food.
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Cordyceps , Adenosina , Animais , Humanos , Rim , MicélioRESUMO
Purpose: Analysis of ferning formation after tear drop desiccation on a glass slide has been applied as a simple method to examine tear normality and is referred to as the tear ferning (TF) test. Despite use of the TF test in clinical settings and in some animals, thus far no TF test protocol has been developed for the mouse model. This study aimed to establish a mouse TF test protocol that can be used for dry eye research using the mouse as the study model. Methods: Tear samples were collected from 24 healthy mice after repeated flushes with 2, 5, 10, or 20 µL wash solutions, either 0.9% NaCl saline or sterile water, on the ocular surface. After sample collection, TF tests were performed at variable drop volumes (2-20 µL), at a relative humidity of either 46% ± 2% or 53% ± 2%, and with temperature fixed at 24°C ± 2°C for comparison. Moreover, the influence of osmolarity (between 280 and 360 mOsm/L) and pH values (6.5-8.0) and the effect of centrifugation (4000 rpm, 10 minutes) on ferning formation were examined. Reproducibility and ferning storage stability were also determined. Results: An optimized protocol was established with relative humidity at 46% ± 2% and drop aliquot at 2 µL, using 0.9% NaCl saline as the wash solution. Using sterilized water as the wash solution did not result in any crystalloid formation. Centrifugation did not aid ferning formation in any of the samples. Higher osmolarity increased ferning formation from grades between 0 to 1 to grades between 2 to 3, but pH values that varied between 6.5 and 8.0 did not affect ferning formation. The established mouse TF test protocol also displayed reproducibility and storage stability. Conclusions: A TF test protocol for the mouse model was established that could be used for comparative analyses under various ocular surface disease conditions. Translational Relevance: This mouse TF test protocol will facilitate the application of basic research into the mouse model to clinical care.
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Síndromes do Olho Seco , Lágrimas , Animais , Síndromes do Olho Seco/diagnóstico , Olho , Camundongos , Concentração Osmolar , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: To investigate the efficacy and safety of three H. erinaceus mycelia (EAHE) capsules (350 mg/capsule; containing 5 mg/g erinacine A active ingredient) per day for the treatment of patients with mild Alzheimer's Disease (AD). METHODS: This study comprised a 3-week no-drug screening period, followed by a 49-week double-blind treatment period with 2-parallel groups in which eligible patients were randomized to either three 5 mg/g EAHE mycelia capsules per day or identical appearing placebo capsules. Cognitive assessments, ophthalmic examinations, biomarker collection, and neuroimaging were followed throughout the study period. RESULTS: After 49 weeks of EAHE intervention, a significant decrease in Cognitive Abilities Screening Instrument score was noted in the placebo group, a significant improvement in Mini-Mental State Examination score was observed in the EAHE group and a significant Instrumental Activities of Daily Living score difference were found between the two groups. In addition, EAHE group achieved a significantly better contrast sensitivity when compared to the placebo group. Moreover, only the placebo group observed significantly lowered biomarkers such as calcium, albumin, apolipoprotein E4, hemoglobin, and brain-derived neurotrophic factor and significantly elevated alpha1-antichymotrypsin and amyloid-beta peptide 1-40 over the study period. Using diffusion tensor imaging, the mean apparent diffusion coefficient (ADC) values from the arcuate fasciculus region in the dominant hemisphere significantly increased in the placebo group while no significant difference was found in the EAHE group in comparison to their baselines. Moreover, ADC values from the parahippocampal cingulum region in the dominant hemisphere significantly decreased in the EAHE group whereas no significant difference was found in the placebo group when compared to their baselines. Lastly, except for four subjects who dropped out of the study due to abdominal discomfort, nausea, and skin rash, no other adverse events were reported. CONCLUSION: Three 350 mg/g EAHE capsules intervention for 49 weeks demonstrated higher CASI, MMSE, and IADL scores and achieved a better contrast sensitivity in patients with mild AD when compared to the placebo group, suggesting that EAHE is safe, well-tolerated, and may be important in achieving neurocognitive benefits. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT04065061.
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Purpose: Several pieces of epidemiologic evidence have indicated PM2.5 (particulate matter with a diameter of 2.5 µm or less) as a causing factor of allergic conjunctivitis, but without experimental elucidation of mechanism. In the present study, PM2.5 in solution was directly applied to the mouse ocular surface to elucidate whether PM2.5 might cause allergic conjunctivitis, and its underlying mechanisms were analyzed. Methods: ICR mice were challenged for 18 consecutive days with eye drops containing PM2.5 at 3.2, 6.4, and 12.8 mg/mL in 0.9% NaCl saline, along with the controls prepared in parallel without PM2.5 and another control group treated with both PM2.5 at 12.8 mg/mL and artificial tears. On day 19, the whole eyes and meibomian glands were harvested for histopathological analyses and assessment of clinical scoring, tear volume, tear breakup time, and tear ferning. Furthermore, goblet cells by periodic acid Schiff stain and infiltrated eosinophils by Giemsa stain were quantified and compared among study groups. Results: Clinical scoring showed more eyelid edema, tearing, and scratching behaviors, with longer tear breakup time under the influence of increased PM2.5 concentrations. Tear ferning assay showed less tear crystal formation and decreased crystal branches after exposure to PM2.5. In addition, higher goblet cell density in the upper palpebral conjunctiva and extensive eosinophil infiltration in the entire conjunctiva and in the meibomian glands were induced by PM2.5. Conclusions: These results demonstrate that PM2.5 can induce symptoms similar to clinical allergic conjunctivitis and that the murine acute allergic conjunctivitis model can be induced by direct exposure to PM2.5.
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Conjuntivite Alérgica/etiologia , Material Particulado/efeitos adversos , Animais , Modelos Animais de Doenças , Edema/patologia , Exposição Ambiental/efeitos adversos , Pálpebras/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Tamanho da Partícula , Lágrimas/metabolismoRESUMO
Exosomes, also called extracellular vesicles (EVs), are membranous structures measuring between 40 and 100â¯nm. Exosomes, secreted by various cells of the human body into body fluids, contain protein, mRNA, miRNA, and signaling molecules. Physiologically, exosomes assist in the intercellular transport of protein and RNA. Immunologically, exosomes exhibit antigen-presenting capability. In recent studies, exosomes were found to be associated with the pathophysiology of cardiovascular, renal, neurological, and ocular diseases. In addition, exosomes may play a major role in cancer metastasis. Due to the extremely small size and scarcity of exosomes in living samples, many early studies utilized sucrose density gradient ultracentrifugation for exosome collection. However, sucrose density gradient ultracentrifugation is rather time consuming and requires large biological sample quantities. Newer exosome studies combined immunoaffinity and microfluidic system approaches for more efficient exosome collection. Our review summarizes existing methods for EV isolation and notes their advantages and disadvantages. These promising approaches are all characterized by isolation efficiency, and savings in cost, labor, and time. Optimization of current methods is a necessary step toward clinically-relevant diagnostic product production, but the fact that EVs are already widely used in disease diagnosis and treatment encourages continued efforts.
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Centrifugação com Gradiente de Concentração , Exossomos/química , Cromatografia de Afinidade , Humanos , Técnicas Analíticas MicrofluídicasRESUMO
Visual fatigue is commonly encountered in modern life. Clinical visual fatigue characteristics caused by 2-D and 3-D animations may be different, but have not been characterized in detail. This study tried to distinguish the differential effects on visual fatigue caused by 2-D and 3-D animations. A total of 23 volunteers were subjected to accommodation and vergence assessments, followed by a 40-min video game program designed to aggravate their asthenopic symptoms. The volunteers were then assessed for accommodation and vergence parameters again and directed to watch a 5-min 3-D video program, and then assessed again for the parameters. The results support that the 3-D animations caused similar characteristics in vision fatigue parameters in some specific aspects as compared to that caused by 2-D animations. Furthermore, 3-D animations may lead to more exhaustion in both ciliary and extra-ocular muscles, and such differential effects were more evident in the high demand of near vision work. The current results indicated that an arbitrary set of indexes may be promoted in the design of 3-D display or equipments.
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Acomodação Ocular/fisiologia , Astenopia/fisiopatologia , Imageamento Tridimensional , Jogos de Vídeo , Adulto , Feminino , Humanos , Masculino , Testes VisuaisRESUMO
Advances in optical and electronic technology can immensely reduce noise in images and greatly enhance human visual recognition. However, it is still difficult for human eyes to identify low-resolution thermal images, due to the limits imposed by psychological and physiological factors. In addition, changes in monitor brightness and lens resolution may also interfere with visual recognition abilities. To overcome these limitations, we devised a suitable and effective recognition method which may help the military in revising the shape parameters of long-range targets. The modulation transfer function was used as a basis to extend the visual characteristics of the human visual model and a new model was produced through the incorporation of new shape parameters. The new human visual model was next used in combination with a backpropagation neural network for better recognition of low-resolution thermal images. The new model was then tested in experiments and the results showed that the accuracy rate of recognition steadily rose by over 95%.
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Modelos Neurológicos , Rede Nervosa/fisiologia , Inibição Neural/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Retina/fisiologia , Córtex Visual/fisiologia , Simulação por Computador , Percepção de Forma , Humanos , Percepção VisualRESUMO
PURPOSE: This study investigated the effects of dietary α-lipoic acid (α-LA) against ultraviolet B (UVB)-induced corneal and conjunctival degeneration in a mouse model. METHODS: Female CBA mice were randomly divided into five study groups, including blank control, UVB without α-LA, and UVB with dietary α-LA at 1, 10, and 100 mg/kg body weight. Following UVB exposure, corneal surfaces were assessed along with immunohistochemistry for nuclear factor-κB (NF-κB), cyclooxygenase-2 (COX-2), malondialdehyde (MDA) accumulation, and P63⺠basal cell distribution. Matrix metalloproteinase (MMP)-2 and MMP-9 activities were determined by gelatin zymography. ELISA assay was performed to confirm the findings of immunohistochemistry for NF-κB, COX-2, and MDA, along with the levels of TNF-α and IL-6. Tear production and goblet cell density were determined after tear strip assay and periodic acid Schiff staining, respectively. RESULTS: The results showed that UVB irradiation caused corneal surface damage, polymorphonuclear leukocyte infiltration, and loss of P63⺠basal cells. Dietary α-LA ameliorated the UVB-induced corneal damage while simultaneously reducing MDA accumulation and maintaining P63⺠basal cell survival. NF-κB-p65, COX-2, TNF-α, IL-6, and MMP-9 activity were all reduced by dietary α-LA. In addition, α-LA helped to reverse aqueous tear reduction, conjunctival squamous epithelium metaplasia, and goblet cell loss after UVB exposure. CONCLUSIONS: Dietary α-LA can prevent UVB-induced corneal damage and can be used as a prophylactic agent prior to excessive UVB exposure.
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Túnica Conjuntiva/efeitos da radiação , Doenças da Túnica Conjuntiva/prevenção & controle , Córnea/efeitos da radiação , Doenças da Córnea/prevenção & controle , Suplementos Nutricionais , Estresse Oxidativo/efeitos dos fármacos , Ácido Tióctico/administração & dosagem , Animais , Antioxidantes/administração & dosagem , Sobrevivência Celular , Túnica Conjuntiva/metabolismo , Túnica Conjuntiva/patologia , Doenças da Túnica Conjuntiva/etiologia , Doenças da Túnica Conjuntiva/patologia , Córnea/metabolismo , Córnea/patologia , Doenças da Córnea/etiologia , Doenças da Córnea/patologia , Modelos Animais de Doenças , Feminino , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos CBA , Resultado do Tratamento , Raios Ultravioleta/efeitos adversosRESUMO
PURPOSE: Weekly disposable soft contact lenses have been widely used recently, but their shield effects against ultraviolet (UV) irradiation remain to be evaluated. This study investigated the bioprotective effects of several weekly soft contact lenses against UVB irradiation on the corneal surface in a mouse model. METHODS: Fifty ICR mice were randomly divided into five groups: (1) blank control, (2) exposed to UVB without contact lens protection, (3) exposed to UVB and protected with Vifilcon A contact lenses, (4) exposed to UVB and protected with Etafilcon A contact lenses, and (5) exposed to UVB and protected with HEMA+MA contact lenses. The exposure to UVB irradiation was performed at 0.72 J/cm²)/day after anesthesia for a 7-day period, followed by cornea surface assessment for smoothness, opacity, and grading of lissamine green staining. Tissue sections were prepared for hematoxylin and eosin staining and immunohistochemical detection by using antibodies against myeloperoxidase, cytokeratin-5, P63, Ki-67, nuclear factor-kappa B (p65), cyclooxygenase-2, Fas L, and Fas. RESULTS: The results showed impaired corneal surface with myeloperoxidase+ polymorphonuclear leukocyte infiltration into the stroma after UVB exposure, in contrast to the intact status of the blank controls. The corneas with Etafilcon A and HEMA+MA contact lenses maintained more cells positive for cytokeratin-5, P63, and Ki-67 compared to those with Vifilcon A or without contact lens protection. Furthermore, less proinflammatory factors, including nuclear factor-kappa (p65), cyclooxygenase-2, Fas L, and Fas, were induced in the corneas protected by Etafilcon A and HEMA+MA. CONCLUSIONS: This study demonstrated various protective effects of weekly disposable contact lenses against UVB irradiation. The mouse model used in the present study may be used extensively for in vivo assessment of UV shield efficacy.
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Lentes de Contato , Córnea/efeitos da radiação , Raios Ultravioleta , Animais , Morte Celular/efeitos da radiação , Córnea/patologia , Células Epiteliais/patologia , Células Epiteliais/efeitos da radiação , Epitélio Corneano/patologia , Epitélio Corneano/efeitos da radiação , Feminino , Mediadores da Inflamação/metabolismo , Cristalino/patologia , Cristalino/efeitos da radiação , Leucócitos Mononucleares/patologia , Leucócitos Mononucleares/efeitos da radiação , Camundongos , Camundongos Endogâmicos ICR , Modelos Animais , Propriedades de Superfície/efeitos da radiaçãoRESUMO
PURPOSE: The aim was to screen children from Grades 1 to 6 in an urban elementary school in Central Taiwan for visual deficits and associated parameters and, as an extension, to examine the acceptance of cycloplegic therapy as well as the lag in optimal vision correction. METHODS: Of 900 students in one school, 731 participated in the study, with parental consent. Data from 694 students, who had also completed a vision correction history were analysed. In addition to body height and weight, the screening included vision, non-cycloplegic autorefraction and distance retinoscopy, axial length and functional testing. RESULTS: There was a decrease in students with vision of 1.0 or better from 55.8 per cent in Grade 1 to 20.0 per cent in Grade 6. The decreases between Grades 2 and 3 and Grades 5 and 6 were significant. These trends were in general agreement with those based on refractive error and axial length. The students had abnormal functional findings including: stereoscopic vision, 9.2 per cent; cover tests, 14.1 per cent; pupillary responses, 13.8 per cent; and less commonly in extraocular muscular functions (3.0 per cent) and colour vision (5.2 per cent). A full 40 per cent of students received cycloplegic therapy with 25 per cent dropping out for various reasons. These cases were generally associated with lower vision and higher myopia. A lag between subnormal vision and optical correction was also observed with 55.1 per cent apparently not optimally corrected. Other parameters, including body height, weight and body mass index were not correlated with vision or refractive error. CONCLUSIONS: Age-dependent increase in the prevalence of myopia appears to continue despite the common practice of topical cycloplegic therapy in Taiwan. Timely correction of the refractive error is also lacking. While maintaining a visual acuity of 1.0 or better for all students at all times is not possible, this lag might be shortened by more frequent screening and/or direct provision of optical aids.