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1.
Ophthalmic Physiol Opt ; 43(2): 202-211, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36464862

RESUMEN

PURPOSE: To use the Health Belief Model (HBM) to understand daily disposable (DD) soft contact lens (SCL) wearers' attitudes and beliefs. METHODS: A convenience sample of DD SCL wearers (18-33 years) was enrolled at two sites. Participants were queried about demographics, SCL wear and HBM constructs. Rasch analysis was used to assess the psychometric properties of the survey instrument and generate scores for each HBM subscale. ANOVA was used to determine relationships among HBM constructs, subject demographics and DD SCL-related health behaviours. RESULTS: One hundred people participated (mean ± SD), age = 24.2 ± 3.9 years, 76% female. Thirty-seven percent reported sleeping in DD SCLs and 25% reported reusing DD SCLs. Self-report of reusing DD SCLs was associated with scores on the benefits: reuse (p = 0.02) and barriers (p = 0.007) subscales, and sleeping in lenses was associated with scores on the susceptibility (p = 0.05), benefits: wear behaviours (p = 0.006) and barriers (p = 0.01) subscales. Rasch analysis showed some subscales demonstrated multidimensionality. CONCLUSIONS: Selected health belief constructs were associated with DD SCL-related behaviours including reusing and overnight wear. Increased understanding of SCL attitudes and beliefs could inform patient education and interventions to decrease risks associated with improper SCL wear.


Asunto(s)
Lentes de Contacto Hidrofílicos , Humanos , Femenino , Adulto Joven , Adulto , Masculino , Encuestas y Cuestionarios , Autoinforme , Equipos Desechables , Actitud , Modelo de Creencias sobre la Salud
2.
FASEB J ; 35(10): e21899, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34569661

RESUMEN

The cornea of the eye differs from other mucosal surfaces in that it lacks a viable bacterial microbiome and by its unusually high density of sensory nerve endings. Here, we explored the role of corneal nerves in preventing bacterial adhesion. Pharmacological and genetic methods were used to inhibit the function of corneal sensory nerves or their associated transient receptor potential cation channels TRPA1 and TRPV1. Impacts on bacterial adhesion, resident immune cells, and epithelial integrity were examined using fluorescent labeling and quantitative confocal imaging. TRPA1/TRPV1 double gene-knockout mice were more susceptible to adhesion of environmental bacteria and to that of deliberately-inoculated Pseudomonas aeruginosa. Supporting the involvement of TRPA1/TRPV1-expressing corneal nerves, P. aeruginosa adhesion was also promoted by treatment with bupivacaine, or ablation of TRPA1/TRPV1-expressing nerves using RTX. Moreover, TRPA1/TRPV1-dependent defense was abolished by enucleation which severs corneal nerves. High-resolution imaging showed normal corneal ultrastructure and surface-labeling by wheat-germ agglutinin for TRPA1/TRPV1 knockout murine corneas, and intact barrier function by absence of fluorescein staining. P. aeruginosa adhering to corneas after perturbation of nerve or TRPA1/TRPV1 function failed to penetrate the surface. Single gene-knockout mice showed roles for both TRPA1 and TRPV1, with TRPA1-/- more susceptible to P. aeruginosa adhesion while TRPV1-/- corneas instead accumulated environmental bacteria. Corneal CD45+/CD11c+ cell responses to P. aeruginosa challenge, previously shown to counter bacterial adhesion, also depended on TRPA1/TRPV1 and sensory nerves. Together, these results demonstrate roles for corneal nerves and TRPA1/TRPV1 in corneal resistance to bacterial adhesion in vivo and suggest that the mechanisms involve resident immune cell populations.


Asunto(s)
Adhesión Bacteriana , Córnea , Pseudomonas aeruginosa/metabolismo , Canal Catiónico TRPA1/metabolismo , Canales Catiónicos TRPV/metabolismo , Animales , Córnea/inervación , Córnea/metabolismo , Córnea/microbiología , Femenino , Masculino , Ratones , Ratones Noqueados , Canal Catiónico TRPA1/genética , Canales Catiónicos TRPV/genética
3.
Optom Vis Sci ; 97(7): 518-525, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32697559

RESUMEN

SIGNIFICANCE: Visual demands today incorporate a significant amount of time using digital devices. Results of this randomized crossover study of spherical and toric contact lenses demonstrated that participants were able to read smaller print size more comfortably and preferred toric contact lenses when using digital devices. PURPOSE: The purpose of this study was to assess how toric contact lens correction affects subjective and objective outcomes of astigmatic patients using real-world digital devices. METHODS: Adult participants, aged between 20 and 38 years with -0.75 to -1.50 D of astigmatism were enrolled in this double-masked randomized crossover 10-day study of Alcon Dailies Aqua Comfort Plus Sphere and Toric (Alcon, Geneva, Switzerland) contact lenses. Electronic high- and low-contrast near logMAR visual acuity and contrast sensitivity were tested. Reading performance was assessed using custom iPad applications; one used a reading sentences test, whereas the other analyzed zoom, contrast, and distance with website-based articles. Participants completed the Near Activity Visual Questionnaire and stated their preferred contact lens correction. RESULTS: Thirty seven participants were screened, 35 participants were enrolled, and 34 participants completed the study. Toric lens correction improved near high- and low-contrast visual acuity by 0.5 to 1 full line (P < .0001) and allowed participants to read one line smaller text on the iPad (P = .01). Participants increased the zoom 11% (P = .004) and the contrast 4% (P = .006) more with spherical lenses while reading articles. Participants held the iPad at approximately the same distance, about 33 cm (P = .63). Eighty five percent of participants preferred the toric correction (P < .0001). Participants reported improved satisfaction with toric lens correction (P = .0002) and noticed the most benefit with tasks such as reading small print and labels/instructions. CONCLUSIONS: This study used digital devices to demonstrate realistic benefits of toric contact lens designs for astigmatic patients.


Asunto(s)
Astigmatismo/fisiopatología , Astigmatismo/terapia , Computadores , Lentes de Contacto Hidrofílicos , Agudeza Visual/fisiología , Adulto , Sensibilidad de Contraste/fisiología , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Lectura , Refracción Ocular/fisiología , Encuestas y Cuestionarios , Adulto Joven
4.
Ophthalmic Physiol Opt ; 40(6): 770-777, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32955730

RESUMEN

PURPOSE: Type 2 diabetes (T2DM) is a leading cause of visual impairment. Its precursor, prediabetes (preDM), is growing in numbers every year. While it is well known that T2DM causes changes in retinal function early in the disease process, it is likely that some of these changes emerge during the preDM stage. This study evaluates retinal function measures in patients with preDM to determine if there are differences in colour vision, contrast sensitivity (CS), and multifocal electroretinogram (mfERG) measures present before T2DM is diagnosed. METHODS: The L'Anthony desaturated D-15 test, Mars Chart CS test, and mfERG were administered on the right eye of 43 participants; 15 controls (HbA1c ≤ 5.6%), 17 with preDM (HbA1c 5.7%-6.4%), and 11 with T2DM (either physician diagnosed or with untreated HbA1c ≥ 6.5%). HbA1c values were measured at the time of the other tests. Colour vision confusion scores (CVCS) were calculated from the D-15 using the method developed by Torok. Multivariate regression (which controlled for age differences) was used to evaluate the relationship of HbA1c and functional measures. Kruskal-Wallis tests were also used to evaluate differences between groups with post-hoc analysis. RESULTS: CVCSs were significantly different between the three groups (p = 0.009). There was an association between higher CVCS and higher HbA1c values across all groups as well as specifically within the preDM group when controlling for age (R2  = 0.29, p = 0.01 and R2  = 0.39, p = 0.02 respectively). Multivariate regression of all of the functional tests together and HbA1c found only colour vision remained significant, indicating that the functional examination metrics may provide redundant data, with similar changes in prediabetes where colour vision may be the strongest indicator early in the process. CONCLUSIONS: Patients with prediabetes have functional changes that can be measured in the retina before the diagnosis of diabetes, with the L'Anthony D-15 colour vision test providing the strongest association with glucose dysregulation in this population. This has important implications for follow up and screening for diabetes within optometric practices. Further studies are needed to follow these patients over time to see how and when these metrics change.


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Estado Prediabético/fisiopatología , Retina/fisiopatología , Agudeza Visual , Adulto , Anciano , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Electrorretinografía , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Estado Prediabético/sangre , Factores de Riesgo
5.
Eye Contact Lens ; 44 Suppl 1: S221-S227, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28328726

RESUMEN

OBJECTIVE: To assess the incidence of adverse events during the use of a povidone-iodine disinfecting solution (cleadew) and the microbial contamination in contact lens cases. METHODS: A prospective, single-center, open-label, controlled study evaluating the use of cleadew cleaning and disinfecting system in existing daily wear soft contact lens wearers over a 3-month period was conducted. Ocular signs and symptoms during lens wear were assessed at baseline and after 1 and 3 months of using cleadew. Contact lens cases were assessed for the frequency of microbial contamination and the types of microbes, using traditional microbial culture, followed by identification of bacteria using 16S rRNA sequencing. RESULTS: Use of cleadew was well tolerated. There was reduction in corneal staining (0.5±0.5 at 3 months of use) compared with the participant's habitual multipurpose disinfecting system (1.1±1.0); all other clinical signs were not significantly different. There were no cases of solution-induced corneal staining. There was a low adverse event rate of 0.8% per 100 participant-months. Contact lens case contamination was low, with 30% of cases having no culturable microbes. Comparison with previously published data showed that use of cleadew resulted in low frequencies of Gram-positive (49%) and fungal (8%) contamination and a low, but higher than some other disinfecting solutions, level of Gram-negative bacteria. CONCLUSIONS: Cleadew cleaning and disinfecting system was associated with low levels of adverse events during use. Contact lens cases were significantly less frequently contaminated than for some other types of disinfecting solutions.


Asunto(s)
Soluciones para Lentes de Contacto/efectos adversos , Lentes de Contacto Hidrofílicos/efectos adversos , Desinfección/métodos , Infecciones Bacterianas del Ojo/prevención & control , Povidona Yodada/farmacología , Adolescente , Adulto , Anciano , Antiinfecciosos Locales/farmacología , Lentes de Contacto Hidrofílicos/microbiología , Contaminación de Medicamentos , Contaminación de Equipos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Adulto Joven
6.
Invest Ophthalmol Vis Sci ; 65(3): 8, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38466283

RESUMEN

Purpose: Contact lens wear induces corneal parainflammation involving increased immune cell numbers after 24 hours' (CD11c+, Lyz2+, γδ-T cells) and six days' (Ly6G+ cells) wear. We investigated the time course of onset and resolution of these responses. Methods: LysMcre or C57BL/6J mice were fitted with a contact lens (four to 48 hours). Contralateral eyes did not wear lenses. After lens removal, Lyz2+, MHC-II+ or Ly6G+ cells were examined by quantitative imaging. RT-qPCR determined cytokine gene expression. Results: Lens wear for 24 hours increased corneal Lyz2+ cells versus contralateral eyes approximately two-fold. Corneas remained free of visible pathology. The Lyz2+ response was not observed after four or 12 hours' wear, nor after 12 hours' wear plus 12 hours' no wear. Lens removal after 24 hours' wear further increased Lyz2+ cells (∼48% after one day), which persisted for four days, returning to baseline by seven days. Lyz2+ cells in contralateral eyes remained at baseline. MHC-II+ cells showed a similar response but without increasing after lens removal. Lens wear for 48 hours showed reduced Lyz2+ cells versus 24 hours' wear with one day discontinuation, correlating with reduced IL-1ß and IL-18 gene expression. Lens wear for 24 hours did not induce Ly6G+ responses six days after removal. Conclusions: Lens-induced corneal parainflammation involving Lyz2+ cells requires 24 hours' wear but persists after lens discontinuation, requiring seven days for reversal. Lens wear for 48 hours may suppress initial Lyz2+ cell and cytokine responses. The significance of parainflammation during and after lens wear remains to be determined.


Asunto(s)
Lentes de Contacto , Cristalino , Ratones , Animales , Ratones Endogámicos C57BL , Lentes de Contacto/efectos adversos , Córnea , Citocinas/genética
7.
Invest Ophthalmol Vis Sci ; 64(11): 21, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37585189

RESUMEN

Purpose: Contact lens wear can induce corneal parainflammation involving CD11c+ cell responses (24 hours), γδ T cell responses (24 hours and 6 days), and IL-17-dependent Ly6G+ cell responses (6 days). Topical antibiotics blocked these CD11c+ responses. Because corneal CD11c+ responses to bacteria require transient receptor potential (TRP) ion-channels (TRPA1/TRPV1), we determined if these channels mediate lens-induced corneal parainflammation. Methods: Wild-type mice were fitted with contact lenses for 24 hours or 6 days and compared to lens wearing TRPA1 (-/-) or TRPV1 (-/-) mice or resiniferatoxin (RTX)-treated mice. Contralateral eyes were not fitted with lenses. Corneas were examined for major histocompatibility complex (MHC) class II+, CD45+, γδ T, or TNF-α+ cell responses (24 hours) or Ly6G+ responses (6 days) by quantitative imaging. The quantitative PCR (qPCR) determined cytokine gene expression. Results: Lens-induced increases in MHC class II+ cells after 24 hours were abrogated in TRPV1 (-/-) but not TRPA1 (-/-) mice. Increases in CD45+ cells were unaffected. Increases in γδ T cells after 24 hours of wear were abrogated in TRPA1 (-/-) and TRPV1 (-/-) mice, as were 6 day Ly6G+ cell responses. Contralateral corneas of TRPA1 (-/-) and TRPV1 (-/-) mice showed reduced MHC class II+ and γδ T cells at 24 hours. RTX inhibited lens-induced parainflammatory phenotypes (24 hours and 6 days), blocked lens-induced TNF-α and IL-18 gene expression, TNF-α+ cell infiltration (24 hours), and reduced baseline MHC class II+ cells. Conclusions: TRPA1 and TRPV1 mediate contact lens-induced corneal parainflammation after 24 hours and 6 days of wear and can modulate baseline levels of resident corneal immune cells.


Asunto(s)
Lentes de Contacto , Factor de Necrosis Tumoral alfa , Animales , Ratones , Córnea/metabolismo , Antígenos de Histocompatibilidad Clase II/metabolismo , Canales Iónicos , Canal Catiónico TRPA1/genética , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
8.
Ocul Surf ; 28: 79-89, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36758675

RESUMEN

PURPOSE: Previously, using a murine model, we reported that contact lens (CL) wear induced corneal parainflammation involving CD11c+ cells after 24 h and Ly6G+ cells (neutrophils) after 5-6 days. Here, we investigated the role of IL-17 and γδ T cells in the CL-induced neutrophil response. METHODS: CL-wearing C57BL/6 wild-type (WT) mice were compared to lens-wearing IL-17A/F single or double gene knock-out mice, or mice treated with UC7-13D5 monoclonal antibody to functionally deplete γδ T cells. Contralateral eyes served as no lens wear controls. Corneal Ly6G+ and γδ T cell responses were quantified as was expression of genes encoding pro-inflammatory cytokines IL-17A/F, IL-ß, IL-18 and expression of IL-17A/F protein. RESULTS: After 6 days lens wear, WT corneas showed Ly6G+ cell infiltration while remaining free of visible pathology. In contrast, lens-wearing corneas of IL-17AF (-/-), IL-17A (-/-) mice and γδ T cell-depleted mice showed little or no Ly6G+ cell infiltration. No Ly6G+ cell infiltration was detected in contralateral eye controls. Lens-wearing WT corneas also showed a significant increase in γδ T cells after 24 h that was maintained after 6 days of wear, and significantly increased cytokine gene expression after 6 days versus contralateral controls: IL-18 & IL-17A (∼3.9 fold) and IL-23 (∼6.5-fold). Increased IL-17A protein (∼4-fold) was detected after 6 days lens wear. γδ T cell-depletion abrogated these lens-induced changes in cytokine gene and protein expression. CONCLUSION: Together, these data show that IL-17A and γδ T cells are required for Ly6G+ cell (neutrophil) infiltration of the cornea during contact lens-induced parainflammation.


Asunto(s)
Lentes de Contacto , Interleucina-17 , Ratones , Animales , Interleucina-17/genética , Interleucina-17/metabolismo , Interleucina-18/metabolismo , Ratones Endogámicos C57BL , Linfocitos T/metabolismo , Córnea/metabolismo , Citocinas/metabolismo , Ratones Noqueados
9.
Sci Rep ; 12(1): 10655, 2022 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-35739166

RESUMEN

Previously we reported contact lens-induced CD11c+ cell responses in healthy mouse corneas, a phenomenon that also occurs in humans. To test involvement of ocular-associated bacteria, the impact of topical antibiotics on corneal CD11c+ cell populations during 24 h of lens wear was examined. Corneas were treated with gentamicin and ofloxacin (0.3%) or gentamicin alone, some also treated prior to lens wear (24 h). Contralateral PBS-treated eyes served as controls. CD11c-YFP (Yellow Fluorescent Protein) mice allowed CD11c+ cell visualization. Viable bacteria, on the ocular surface or contact lens, were labeled using FISH (16S rRNA-targeted probe) or click-chemistry (alkDala). Antibiotic treatment reduced baseline CD11c+ cell numbers without lens wear and suppressed CD11c+ cell responses to lens wear if corneas were both pretreated and treated during wear. Few bacteria colonized corneas or lenses under any circumstances. Conjunctival commensals were significantly reduced by antibiotics with or without lens wear, but minimally impacted by lens wear alone. Deliberate inoculation with conjunctival commensals triggered CD11c+ cell responses irrespective of antibiotic pretreatment. These results suggest that while lens wear does not necessarily increase quantifiable numbers of conjunctival commensals, those neutralized by antibiotics play a role in lens-associated CD11c+ cell responses and maintaining baseline CD11c+ cell populations.


Asunto(s)
Antibacterianos , Lentes de Contacto , Animales , Antibacterianos/metabolismo , Antibacterianos/farmacología , Bacterias , Antígeno CD11c/metabolismo , Recuento de Células , Córnea/metabolismo , Gentamicinas/metabolismo , Gentamicinas/farmacología , Ratones , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo
10.
Cont Lens Anterior Eye ; 44(4): 101357, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32807659

RESUMEN

PURPOSE: This study examined the rate and level of microbial contamination of silver and non-silver (control) barrel contact lens storage cases in vivo. METHODS: A prospective, single-centre, randomized, double blinded, crossover study was conducted to evaluate the efficacy of silver and control barrel cases used with an Oxipol™-based disinfecting solution over a two-month period. Lens cases were collected, and the frequency, type and level of microbial contamination evaluated using viable culture and standard identification methods. Questionnaires were used to assess the contact lens-related hygiene compliance of the participants. RESULTS: Forty eight daily contact lens wearers completed the study. Overall, 27 % of silver and 35 % control lens cases (P > 0.05) were contaminated, predominantly with Gram-positive bacteria. Only, 12 % of participants had good compliance, with 46 % having average compliance and 43 % poor compliance. Compliance score was not associated with level of microbial contamination. However, the use of hydrogel lenses in combination with silver cases compared to non-silver barrel cases resulted significantly greater numbers of bacteria colonising cases. CONCLUSION: The present investigation demonstrated that the use of silver barrel cases does not reduce the overall rate and level of bacterial contamination, but that using hydrogel lenses in combination with silver cases resulted in higher numbers of bacteria isolated from cases.


Asunto(s)
Lentes de Contacto , Plata , Soluciones para Lentes de Contacto , Estudios Cruzados , Desinfección , Contaminación de Equipos/prevención & control , Humanos , Estudios Prospectivos
11.
J Neurosci Methods ; 361: 109266, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34166700

RESUMEN

BACKGROUND: The tortuosity of nerve fibers has been shown to be important for identifying and monitoring clinically relevant manifestations resulting from of a variety of ocular and systemic disease pathologies and disorders. However, quantifying tortuosity in dense neurite networks can prove challenging, as existing methods require manual scoring and/or complete segmentation of the neurite network. NEW METHOD: We measured neurite tortuosity by quantifying the degree of directional coherence in the Fourier transform of segmented neurite masks. This allowed for the analysis of neurite tortuosity without requiring complete segmentation of the neurite network. We were also able to adapt this method to measure tortuosity at different length and size scales. RESULTS: With this novel method, neurite tortuosity was accurately quantified in simulated data sets at multiple length scales and scale variant and scale invariant tortuosity was accurately distinguished. Use of this method on images of murine corneal neurites correctly distinguished known differences between neurite tortuosity in the peripheral and central cornea. COMPARISON WITH EXISTING METHOD(S): Other methods require complete segmentation of neurites, which can be prohibitive in dense and/or sparsely labeled neurite networks such as in the cornea. Additionally, other methods require manual curation, manual scoring, or generation of a curated training set, while our novel method directly measures tortuosity as an intrinsic property of the image. CONCLUSIONS: We report the use of Fourier transforms for quantification of neurite tortuosity at multiple length scales, and with an image input that contains incompletely segmented neurites. This new method does not require manual training or curation, allowing a direct and rapid measurement of neurite tortuosity, thereby enhancing the accuracy and utility of neurite tortuosity measurements for evaluation of ocular and systemic disease pathology.


Asunto(s)
Fibras Nerviosas , Neuritas , Animales , Córnea , Análisis de Fourier , Humanos , Procesamiento de Imagen Asistido por Computador , Ratones
12.
Clin Exp Optom ; 104(1): 42-47, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32945015

RESUMEN

CLINICAL RELEVANCE: While the clinical focus of performance metrics is traditionally based on visual acuity, research from the field of visual impairment has demonstrated that metrics such as reading speed and critical print size correlate much more strongly with subjective patient reported outcomes and assessed ability in real-world tasks. BACKGROUND: More recently, digital device use has increasingly replaced many paper-based tasks. Therefore, this study aimed to assess the correlation between standard acuity/contrast metrics and functional reading ability compared to real-world performance on an iPad-based reading task with astigmatic patients corrected wearing toric and mean spherical equivalent contact lenses. METHODS: Thirty-four adult participants, with -0.75 to -1.50-D of refractive astigmatism, were enrolled in a double-masked cross-over study and fitted with toric and spherical equivalent contact lenses, in random order. A digital application was developed to assess zoom, contrast modifications, the distance at which the tablet was held, blink rate, and time to complete the reading task. High and low contrast near logMAR visual acuity were measured along with reading performance (critical print size and optimal reading speed). RESULTS: The amount participants chose to increase tablet font size (zoom) was correlated with their high-contrast visual acuity with toric correction (r = 0.434, p = 0.010). With best sphere correction, zoom was associated with reading speed (r = -0.450, p = 0.008) and working distance (r = 0.522, p = 0.002). Text zoom was also associated with horizontal (toric: r = 0.898, p < 0.001; sphere: r = 0.880, p < 0.001) and vertical scrolling (toric: r = 0.857, p < 0.001; sphere: r = 0.846, p < 0.001). There was a significant negative association between the selection of text contrast and zoom (toric: r = -0.417, p = 0.0141; sphere: r = -0.385, p = 0.025). CONCLUSION: Real-world task performance allows more robust assessment of visual function than standard visual metrics alone. Digital technology offers the opportunity to better understand the impact of different vision correction options on real-world task performance.


Asunto(s)
Astigmatismo , Lentes Intraoculares , Adulto , Estudios Cruzados , Humanos , Refracción Ocular , Pruebas de Visión , Agudeza Visual
13.
Transl Vis Sci Technol ; 8(3): 52, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31293807

RESUMEN

PURPOSE: We evaluate the in vitro antibacterial activity of silver-copolymerized barrel cases compared to nonsilver barrel cases in combination with a multipurpose disinfecting solution (MPDS). METHODS: The ability of silver and nonsilver cases to reduce the number of adherent Gram-positive and Gram-negative bacteria was assessed. Additionally, the efficacy of silver cases along with MPDS was investigated in the presence of organic soil and contact lenses. Contact lens cases were challenged with 106 colony-forming units (CFU)/mL of five bacterial species. Adherent bacteria were dislodged from lens cases and surviving organisms enumerated. RESULTS: Significantly lower numbers of microbes were recovered from silver cases compared to controls, for all bacterial strains (P < 0.005). The combination of silver case along with MPDS showed added efficacy against Gram-positive and -negative bacteria with a maximum reduction of 3.00 ± 0.5 Log10 CFU/mL, compared to the efficacy of silver cases alone (1.97 ± 0.4 Log10 CFU/mL). The addition of organic soil and a contact lens resulted in a significant (P < 0.005) decrease (a maximum of 1.68 ± 0.2 log10 CFU/mL) in disinfection efficacy when MPDS and either silver or control cases were used. CONCLUSIONS: Silver-copolymerized barrel cases work on conjunction with a hypochlorite producing MPDS in the presence of contact lenses and organic soil to reduce microbial contamination of lens cases. TRANSITIONAL RELEVANCE: Silver-copolymerized barrel contact lens cases show promising in vitro antibacterial activity against bacterial types commonly implicated in contact lens-related corneal infections. This intervention may limit storage case contamination during use and reduce the frequency of contact lens-related microbial disease.

14.
Invest Ophthalmol Vis Sci ; 59(7): 2729-2735, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29860459

RESUMEN

Purpose: The aim of this study was to examine cohesion, coaggregation, and coculture between bacteria commonly isolated from contact lens cases. Methods: Staphylococcus epidermidis, Staphylococcus haemolyticus, Micrococcus luteus, and Acinetobacter radioresistens (two strains each) isolated from contact lens cases of two asymptomatic wearers were used in this study. In the cohesion assay, bacteria were grown, washed, and examined by incubating lens cases with two different types of bacteria sequentially and assessing the number of adhered cells of each isolate. The ability of isolates to interfere with the growth of other isolates was tested by growing strains in cocultures for 24 hours and determining the numbers of cells of individual strains. For coaggregation, equal proportions of two bacterial suspensions were mixed and allowed to coaggregate for 24 hours. Inhibition of coaggregation was tested by the addition of lactose (0.06 M) or sucrose (0.06 M) or pronase. Results: The initial adhesion of M. luteus or A. radioresistens significantly (P < 0.05) enhanced the subsequent adhesion of the staphylococci. The addition of A. radioresistens in liquid media significantly (P < 0.05) enhanced the growth of staphylococci. S. epidermidis or S. haemolyticus coaggregated with M. luteus or A. radioresistens. The degree of coaggregation varied between 30% and 54%. The highest coaggregation (54% ± 5%) was seen between A. radioresistens 22-1 and S. epidermidis 22-1, isolated from the same lens case. Only lactose or sucrose treatment of staphylococci could partly inhibit coaggregation of some pairs. Conclusions: Coaggregation, cohesion, and growth promotion may facilitate the process of bacterial colonization of contact lens cases.


Asunto(s)
Bacterias/crecimiento & desarrollo , Adhesión Bacteriana/fisiología , Lentes de Contacto/microbiología , Contaminación de Equipos , Acinetobacter/crecimiento & desarrollo , Acinetobacter/aislamiento & purificación , Bacterias/aislamiento & purificación , Técnicas Bacteriológicas , Micrococcus luteus/crecimiento & desarrollo , Micrococcus luteus/aislamiento & purificación , Staphylococcus epidermidis/crecimiento & desarrollo , Staphylococcus epidermidis/aislamiento & purificación , Staphylococcus haemolyticus/crecimiento & desarrollo , Staphylococcus haemolyticus/aislamiento & purificación
15.
Invest Ophthalmol Vis Sci ; 58(1): 50-58, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28061510

RESUMEN

Purpose: To examine the coaggregation and cohesion between the commonly isolated bacteria from contact lens cases. Methods: Four or five strains each of commonly isolated bacteria from contact lens cases, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Serratia marcescens, were grown, washed, mixed in equal proportions, and allowed to coaggregate for 24 hours. Lactose (0.06 M), sucrose (0.06 M), and pronase (2 mg/mL; 2 hours, 37°C) were used to inhibit coaggregation. Oral bacterial isolates of Actinomyces naeslundii and Streptococcus sanguinis were used as a positive control for coaggregation. Cohesion was performed with the ocular bacteria that demonstrated the highest level of coaggregation. Production of growth-inhibitory substances was measured by growing strains together on agar plates. Results: The oral bacterial pair showed >80% coaggregation. Coaggregation occurred between ocular strains of S. aureus (2/5) or S. epidermidis (2/5) with P. aeruginosa strains (3/5); 42% to 62%. There was only slight coaggregation between staphylococci and S. marcescens. Staphylococcus aureus coaggregated with S. epidermidis. Lactose or sucrose treatment of S. aureus but pronase treatment of P. aeruginosa reversed the coaggregation. There was no cohesion between the ocular isolates. P. aeruginosa was able to stop growth of S. aureus but not vice versa. Conclusions: This study demonstrated for the first time that ocular isolates of P. aeruginosa and S. aureus could coaggregate, probably through lectin-carbohydrate interactions. However, this may not be related to biofilm formation in contact lens cases, as there was no evidence that the coaggregation was associated with cohesion between the strains.


Asunto(s)
Bacterias/crecimiento & desarrollo , Adhesión Bacteriana , Lentes de Contacto/microbiología , Infecciones Bacterianas del Ojo/microbiología , Bacterias/aislamiento & purificación , Contaminación de Equipos , Humanos
16.
Indian J Pharmacol ; 43(1): 36-9, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21455419

RESUMEN

OBJECTIVES: Adverse drug reactions (ADRs) to psychotropic agents are common and can lead to noncompliance or even discontinuation of therapy. There is paucity of such data in the Indian context. We deemed it worthwhile to assess the suspected ADR profile of psychotropic drugs in an ambulatory setting in a public teaching hospital in Kolkata. MATERIALS AND METHODS: A longitudinal observational study was conducted in the outpatient department (OPD) of the concerned psychiatry unit. Twenty consecutive patients per day, irrespective of their psychiatric diagnosis, were screened for suspected ADRs, 2 days in a week, over 15 months. Adverse event history, medication history and other relevant details were captured in a format as adopted in the Indian National Pharmacovigilance Programme. Causality was assessed by criteria of World Health Organization-Uppsala Monitoring Center (WHO-UPC). RESULTS: We screened 2000 patients (68.69% males, median age 34.4 years), of whom 429 were suspected of having at least one ADR; 84 cases had insufficient evidence about causality (WHO-UMC causality status "unlikely") and were excluded from further analysis. Thus, 17.25% (95% confidence interval: 15.59-18.91%) of our study population reported ADRs with at least "possible" causality. Of 352 events recorded, 327 (92.90%) were "probable" and the rest "possible". None was labeled "certain" as rechallenge was not performed. Patients received a median of 3.2 psychotropic drugs each. Thirty-three different kinds of ADRs were noted, including tremor (19.60%), weight gain (15.34%) and constipation (14.49%). Among the incriminated drugs, antipsychotics represented the majority (57.10%), with olanzapine topping the list. CONCLUSIONS: This study offers a representative profile of ADRs to be expected in psychiatry out-patients in an Indian public hospital. Establishment of a psychotropic drug ADR database can be a worthy long-term goal in the Indian context.

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