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1.
Opt Express ; 30(2): 2693-2710, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209404

RESUMO

We demonstrate accurate estimation of generalized optical signal to noise ratio (GOSNR) for wavelength division multiplexed fiber communication systems using an experimentally trained multi-tasking convolutional neural network while simultaneously estimating linear and nonlinear noise contributions. Using dual-polarized 32-GBaud 16QAM DWDM links we extract learnable features from constellation density matrices and accurately estimate GOSNR while simultaneously estimating linear and nonlinear contributions. Estimation of the OSNRASE, OSNRNL and GOSNR are demonstrated with < 0.5 dB mean absolute error. We also assess the universality of our model within the regime of metro networks by cross-training with data from such links comprised of different fiber types. We demonstrate a path to a practical universal training method that includes additional link parameters. The methods do not require contiguous high-speed sampling, additional hardware nor transmission of special symbols or patterns and are readily implemented in deployed systems.

2.
Optom Vis Sci ; 96(4): 283-290, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30907859

RESUMO

SIGNIFICANCE: This study reports that subjective vision ratings are better indicators of willingness to purchase simultaneous-image contact lenses than visual acuities and are more valuable in evaluating contact lens performance. PURPOSE: The purpose of this study was to investigate the relationship between visual acuities, subjective vision ratings, and willingness to purchase simultaneous-image contact lenses in presbyopes. METHODS: A retrospective analysis of visual acuities, subjective vision ratings, and willingness to purchase from final visits of two masked, crossover clinical trials of nine prototype and four commercially available simultaneous-image contact lenses in 141 presbyopes was performed. Pearson correlation and area under the receiver operating characteristic curve determined correlations between variables. RESULTS: Most subjective vision ratings were weakly correlated (r < 0.3) with visual acuity at all distances and illumination. Moderate correlations (r, 95% confidence intervals) were found between overall vision satisfaction ratings with visual acuity at 40 (-0.34, -0.28 to -0.40) and 50 cm (-0.33, -0.27 to -0.39), near-vision ratings (daytime) with visual acuity at 40 (-0.48, -0.43 to -0.53) and 50 cm (-0.46; -0.41 to -0.51), and intermediate-vision ratings (daytime) with visual acuity at 40 (-0.39, -0.33 to -0.45) and 50 cm (-0.41, -0.35 to -0.46). Highest discrimination for willingness to purchase was with overall vision satisfaction (area under curve, 0.93) and vision stability (daytime; area under curve, 0.77). Ratings from 4 to 9 for vision satisfaction showed a linear increase in willingness to purchase: a 1-unit increase in vision satisfaction increased willingness to purchase by 20%. Ratings lower than 4 had 0% willingness to purchase. Other subjective ratings showed similar relationships, albeit only 10 to 15% increase in willingness to purchase per unit increase for ratings higher than 4. CONCLUSIONS: Subjective vision ratings are a better indicator of simultaneous-image contact lens performance than visual acuity. Overall vision satisfaction and vision stability are key predictors of willingness to purchase. Subjective vision ratings should be used to evaluate performance rather than visual acuity alone.


Assuntos
Lentes de Contato Hidrofílicas , Aceitação pelo Paciente de Cuidados de Saúde , Presbiopia/terapia , Visão Ocular/fisiologia , Acuidade Visual/fisiologia , Adulto , Comportamento do Consumidor , Feminino , Promoção da Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Presbiopia/psicologia , Estudos Prospectivos , Estudos Retrospectivos , Inquéritos e Questionários
3.
Eye Contact Lens ; 45(4): 260-270, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30601291

RESUMO

OBJECTIVE: To assess two prototype contact lenses (CLs) that extend depth of focus through deliberate manipulation of multiple spherical aberration terms (extended depth-of-focus [EDOF]) for visual performance, accommodative and binocular function, and objective static near refraction against a single-vision (SV) CL. METHOD: This was a prospective, randomized, cross-over, single-masked (participant) clinical trial in which 16 myopic children wore 2 prototype CLs (EDOFL/EDOFH) designed for presbyopes and a SV CL, each for one week. Measurements comprised monocular and binocular high-contrast visual acuity (HCVA: 6 m, 40 cm), binocular low-contrast visual acuity (LCVA: 6 m), contrast sensitivity (CS: 6 m), phorias (3 m, 33 cm), monocular-accommodative facility (33 cm), and objective static refraction (spherical equivalent M) at zero, -3, and -5 D vergences. Measurements were taken 10 min after lens insertion. Subjective response was assessed using take-home questionnaires comprising vision clarity (distance/intermediate/near), vision quality (haloes at night/ghosting), vision stability when moving (playing sport/using stairs), and comfort. RESULTS: Single vision was significantly better than both EDOF CLs for monocular HCVA, LCVA, and CS (6 m); vision clarity (distance), ghosting (P≤0.040), and EDOFL for binocular HCVA (6 m, P=0.047). M was significantly closer to the ideal objective static refraction at -3 and -5 D vergences (P≤0.004) with both EDOF compared with SV CLs. There were no differences between CLs for any other variable (P≥0.169). CONCLUSION: Extended depth-of-focus CLs caused minimal disruption to the accommodative and binocular system compared with SV CLs when worn by myopic children. Future EDOF designs for children should reduce the difference between SV for distance vision and vision quality while maintaining the same performance for intermediate and near.


Assuntos
Acomodação Ocular/fisiologia , Lentes de Contato , Percepção de Profundidade/fisiologia , Presbiopia/terapia , Visão Binocular/fisiologia , Acuidade Visual/fisiologia , Adolescente , Criança , Estudos Cross-Over , Desenho de Equipamento , Feminino , Humanos , Masculino , Estudos Prospectivos , Ajuste de Prótese , Método Simples-Cego
4.
Optom Vis Sci ; 95(12): 1096-1104, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30451806

RESUMO

SIGNIFICANCE: The present study highlights the differences between modern daily-disposable multifocal soft contact lenses to assist eye care practitioners in fitting presbyopic contact lens wearers. PURPOSE: The purpose of this study was to compare visual performance of three daily-disposable multifocal contact lenses. METHODS: Presbyopes (n = 72) wore 1-Day Acuvue Moist Multifocal, BioTrue ONEday for Presbyopia, and Dailies AquaComfort Plus Multifocal for 1 week in a prospective, randomized, double-blind, crossover clinical trial. After 1 week, high- and low-contrast visual acuities (HCVA, LCVA) were measured between 6 m and 40 cm and stereopsis at 40 cm. Subjective performance was assessed with 1- to 10-point rating scales for clarity, ghosting, driving vision, vision stability, ease of focusing, overall vision satisfaction, and ocular comfort. Willingness to purchase was reported with categorical responses. Linear mixed models and χ tests were used for analysis, and level of significance was set at 5%. RESULTS: BioTrue provided better HCVA and LCVA at distance than did Acuvue Moist (P ≤ .03). Subjectively, Acuvue Moist was rated lowest for distance clarity, distance ghosting, and driving vision (P ≤ .05). Acuvue Moist provided better HCVA at 70 to 40 cm and LCVA at 1 m to 40 cm than did BioTrue (P ≤ .01) and better LCVA at 1 m to 50 cm than did AquaComfort Plus (P ≤ .02). AquaComfort Plus also provided better HCVA and LCVA at 50 and 40 cm than did BioTrue (P ≤ .03). Acuvue Moist provided better stereopsis than did BioTrue (P = .02). Subjectively, BioTrue was rated lowest for near clarity (P ≤ .007) and lower than Acuvue Moist for intermediate clarity and near ghosting (P ≤ .04). No other differences were found between lenses (P > .05). CONCLUSIONS: BioTrue had better distance performance compared with near, whereas Acuvue Moist performed conversely. AquaComfort Plus performed reasonably overall.


Assuntos
Lentes de Contato Hidrofílicas , Equipamentos Descartáveis , Presbiopia/terapia , Acuidade Visual/fisiologia , Adulto , Idoso , Condução de Veículo , Sensibilidades de Contraste/fisiologia , Estudos Cross-Over , Percepção de Profundidade/fisiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Presbiopia/fisiopatologia , Estudos Prospectivos , Ajuste de Prótese
5.
Eye Contact Lens ; 44 Suppl 1: S167-S172, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28099285

RESUMO

OBJECTIVE: To compare subjective, objective and safety performance of silicone hydrogel (SiHy) daily disposable (DD) with hydrogel (Hy) DD contact lenses. METHOD: Retrospective analysis on approximately 40 participants (Px) each in 5 trials. Lenses grouped into SiHy (delefilcon A, somofilcon A, narafilcon A) and Hy (omafilcon A, nelfilcon A). Participants attended follow-up visits at baseline, 2 weeks, 1 and 3 months. Subjective ratings (1-10 scale), adverse events (percentage of Px), physiological variables (0-4 scale), and wearing time were collected at each visit and compared between groups. RESULT: Trials enrolled 201 Px totally. No differences in age, sex, and lens wear experience were found between SiHy and Hy groups (P≥0.09). There was greater increase in limbal redness from baseline in Hy group (0.18±0.38 vs. 0.02±0.47, P<0.001), whereas conjunctival staining and indentation were less in Hy group (P<0.001). No differences in comfortable wearing time were found between groups (P=0.41), and comfort at insertion, during day, and end of day was also no different (P≥0.71). Incidence of corneal infiltrative events (SiHy vs. Hy: 6.7% vs. 2.5%; P=0.32) and mechanical adverse events (SiHy vs. Hy: 0.0% vs. 0.0%; P=1.00) were no different. CONCLUSION: Though some statistical significance was found between the groups, these differences were within measurement error. Neither material types showed superiority in comfort, and adverse event rates were low with both material types. These findings suggest that choice of material is a patient and practitioner preference; however, for patients at risk of hypoxia-related complications, SiHy materials should be considered.


Assuntos
Lentes de Contato Hidrofílicas , Doenças da Córnea/terapia , Equipamentos Descartáveis , Hidrogéis , Satisfação do Paciente , Silicones , Adulto , Doenças da Córnea/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Lágrimas , Fatores de Tempo
6.
Eye Contact Lens ; 44 Suppl 1: S30-S37, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27341089

RESUMO

OBJECTIVES: To investigate whether adaptation of accommodative responses occurred in non-presbyopic myopes fitted with four multifocal contact lens (MFCL) designs. METHODS: Prospective, subject-masked clinical investigation comprising 40 experienced myopic lens wearers (18-25 years) fitted bilaterally with single-vision (SV) control lens (Air Optix Aqua [Alcon, Fort Worth, TX]) and randomized to two of four test MFCL (Proclear MFCL [Distance and Near] [CooperVision, Pleasanton, CA], Air Optix Aqua MFCL, Purevision MFCL [Bausch & Lomb, Rochester, NY]). Lenses were dispensed on a daily wear basis and worn for a minimum of 8 (maximum 14) days over three assessment visits, with a 1-week wash out between stages. Paraxial curvature matched spherical equivalent (M) was measured with lenses on eye using the BHVI-EyeMapper with an internal movable fixation target positioned at target vergences of +1.00 diopter (D) (fogging) and -2.00 to -5.00 in 1.00 D steps (accommodative stimuli). Accommodative facility was assessed by several flips of ±2.00 D/min (cycles/min) at 33 cm and horizontal phoria with a Howell phoria card at distance (3 m) and near (33 cm). RESULTS: For center-distance MFCL (Proclear D), the spherical equivalent (M) at all near vergences became significantly more negative at the follow-up visits compared with the dispensing visit (P<0.029). For all center-near MFCLs and SV lens, M remained invariant during the adaptation period, however (P≥0.267). At distance, M became significantly less minus with Air Optix Aqua MFCL over time (P=0.049). Accommodative facility increased over the three assessment visits for participants wearing Air Optix Aqua SV, Air Optix Aqua MFCL, and PureVision MFCL (P=0.003). Distance and near horizontal phoria remained stable over the three assessment visits for all lens types (P≥0.181). CONCLUSIONS: Adaptation differences were not consistently found for static accommodative measures gauged by M, as measured with lenses on eye, and phoria but were found in dynamic measures (facility), perhaps indicating some learning effects. Accommodative adaptation seems unlikely to occur with long-term MFCL in non-presbyopes.


Assuntos
Acomodação Ocular/fisiologia , Lentes de Contato Hidrofílicas , Miopia/reabilitação , Adulto , Estudos Cross-Over , Feminino , Humanos , Masculino , Miopia/fisiopatologia , Estudos Prospectivos , Acuidade Visual/fisiologia , Adulto Jovem
7.
Eye Contact Lens ; 44(5): 308-315, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29210828

RESUMO

OBJECTIVE: To investigate whether initial assessment of contact lenses prescribed for myopia control (MC) predicts short-term visual performance. METHOD: Retrospective analysis of 43 participants in a double-masked, randomized, cross-over trial wearing at least one lens: single-vision (SV) lens (1-DAY ACUVUE MOIST) or MC lenses (MiSight or Proclear Multifocal-Distance +2.00D). Participants completed questionnaires at the fitting visit, a take-home questionnaire (THQ) 3 days after fitting and finally at the assessment visit (≥5 days after fitting). Questions comprised vision clarity and lack of ghosting (distance, intermediate, near at day/night time); vision stability; driving vision; overall vision satisfaction and comfort (1-10 scale, 1-point steps); and willingness to purchase based on vision and MC benefit of lens (yes/no response). Visual acuity was measured at fitting and assessment visits. RESULTS: Vision clarity (intermediate and near) was significantly worse at assessment compared with fitting while wearing MC lenses (P<0.001), as was overall vision satisfaction (P<0.001), comfort (P<0.001), and vision stability (P=0.001) while wearing either SV or MC lenses. Participants willing to purchase at assessment visit was 84% with SV and 36% with MC lenses, increasing to 88% (SV, P=1.00) and 61% (MC, P<0.001) if the lenses slowed myopia progression. Visual acuity was no different with either MC or SV lenses at fitting or assessment (P≥0.251). CONCLUSION: Initial performance at fitting did not predict short-term performance for SV or MC lenses. A significant increase in willingness to purchase if lenses slowed myopia progression was observed while wearing MC lenses. Educating patients on the benefits might increase acceptability of MC lenses.


Assuntos
Lentes de Contato Hidrofílicas , Miopia/terapia , Procedimentos Ortoceratológicos/métodos , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Humanos , Miopia/fisiopatologia , Aceitação pelo Paciente de Cuidados de Saúde , Satisfação do Paciente , Estudos Retrospectivos , Acuidade Visual/fisiologia , Adulto Jovem
8.
Eye Contact Lens ; 44 Suppl 2: S157-S163, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29023311

RESUMO

OBJECTIVES: To compare visual performance of extended depth-of-focus (EDOF) prototypes with a new, center-near, commercial, multifocal contact lens. METHODS: Presbyopic participants (n=57) wore 1-Day ACUVUE MOIST MULTIFOCAL (1DAMM) and an EDOF prototype for one week in a double-masked, prospective, cross-over, randomized clinical trial. Manufacturers' guide was used to select the first pair of lens to be fit based on subjective distance refraction and near addition. After one week, high- and low-contrast visual acuities were measured at distance (6 m), intermediate (70 cm) and near (50 and 40 cm), and stereopsis at 40 cm. Subjective performance was assessed on a 1 to 10 numeric rating scale for vision clarity and lack of ghosting at distance, intermediate and near, vision stability, haloes at night time, overall vision satisfaction, and ocular comfort. Linear mixed models were used for analysis and the level of significance was set at 5%. RESULTS: 1DAMM was not significantly different from EDOF for high- or low-contrast visual acuity at any distance, or for stereopsis. Subjectively, EDOF was significantly better than 1DAMM for vision clarity at intermediate (P=0.033) and near (P<0.001), overall lack of ghosting (P=0.012), vision stability (P=0.004), and overall vision satisfaction (P=0.005). For all other subjective variables, there were no differences between EDOF and 1DAMM (P>0.05). CONCLUSIONS: EDOF prototype lenses offer improvements over the newly marketed 1DAMM lenses for several subjective variables.


Assuntos
Lentes de Contato de Uso Prolongado/normas , Presbiopia/reabilitação , Adulto , Estudos Cross-Over , Percepção de Profundidade/fisiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Visão Ocular/fisiologia , Acuidade Visual/fisiologia
9.
Optom Vis Sci ; 94(9): 876-885, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28816867

RESUMO

SIGNIFICANCE: The amount of central or peripheral myopic shift, as induced by different multifocal contact lenses when viewing objects at distance or near, may provide insights on the potential efficacy for slowing eye growth. PURPOSE: The present study aims to compare peripheral refraction and higher-order aberration profiles of four multifocal contact lenses with a single vision control lens. METHODS: Thirty-five myopes (age 21.2 ± 2.1 years) completed the trial, of whom 16 wore Air Optix Aqua and Proclear Multifocal Distance and Near (Group 1, spherical equivalent: -2.90 ± 0.95D), whereas 19 wore Air Optix Aqua, Air Optix Multifocal, and PureVision Multifocal (Group 2, spherical equivalent: -2.95 ± 0.78D). Refraction and aberration profiles with lenses were measured using the BHVI-EyeMapper with (-2.00 to -5.00D in 1.00D steps) and without (+1.00D fogging) accommodation. Data were quantified using M2/4 (2nd and 2nd + 4th order), J0, J45, and higher-order aberration coefficients coma C[3, 1] and spherical aberration C[4, 0]. RESULTS: The center-distance lens exhibited a relative peripheral myopic shift in M2/4 and J0, positive on-axis C[4, 0], negative on-axis C[3, 1] and on-axis M4 was less negative for accommodative demands ≤-3.00D (P < .05). Inversely, the center-near lenses showed a relative peripheral hyperopic shift in M2/4 and J0, negative on-axis C[4, 0], positive on-axis C[3, 1] and on-axis M4 was more negative for demands of -2.00 and -3.00D (P < .05). Independent of lens type, relative peripheral M4 significantly decreased during accommodation. Accounting for C[4, 0], a greater change in relative M profiles and accommodative responses was found for multifocal lenses. CONCLUSIONS: Based on the hypothesis that myopic retinal defocus counters eye growth, center-near multifocal lenses exhibited the preferred on-axis features, i.e., producing a central myopic shift at near compared to the control. The center-distance lens exhibited preferred off-axis features, producing relative peripheral myopia, which increased further during accommodation.


Assuntos
Acomodação Ocular/fisiologia , Lentes de Contato , Miopia/terapia , Refração Ocular/fisiologia , Aberrometria , Adolescente , Adulto , Desenho de Equipamento , Feminino , Humanos , Masculino , Miopia/fisiopatologia , Estudos Prospectivos , Método Simples-Cego , Testes Visuais , Acuidade Visual , Adulto Jovem
10.
Optom Vis Sci ; 94(2): 197-207, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27879499

RESUMO

PURPOSE: To investigate the impact of the primary (PSA) and secondary (SSA) spherical aberration terms on visual performance (VP) in presbyopes, as measured using multifocal (MFCL) soft contact lenses on eye. METHODS: Seventeen presbyopes (age: 55.1 ± 6.9 years) wore seven commercial lenses (four center-near (MFCL N), one center-distance (MFCL D), one bifocal, and one single vision control). Unaided and with each lens on eye, the PSA and SSA terms were obtained with an aberrometer, the BHVI-EyeMapper (low illumination, natural and 4 mm pupil diameter). High- and low-contrast distance visual acuity, contrast sensitivity, high-contrast visual acuities at near, and range of clear vision were measured. In addition, subjective VP variables included clarity of vision at distance and near, ghosting, and overall vision satisfaction. Pearson's correlation was used to determine the association between the PSA and SSA terms and the VP variables. RESULTS: PSA (natural pupil) was more negative (P < .05) with the MFCL N (mean PSA = -0.053 ± 0.080 µm) and bifocal (PSA = +0.005 ± 0.067 µm) lenses and more positive with the MFCL D lens (PSA = +0.208 ± 0.160 µm) than the control (+0.067 ± 0.072 µm). SSA (natural pupil) was significantly more positive for the MFCL N lenses (mean SSA = +0.025 ± 0.029 µm) compared to the control (SSA = -0.001 ± 0.017 µm). PSA and SSA terms were significantly (P < .05) correlated with 78% and 56% of VP variables, respectively, but the correlation coefficients were weak, ranging between |0.210| and |0.334|. Although distance variables showed improved VP with more positive PSA or negative SSA, most near variables showed improved VP with more negative PSA. Range of clear focus was greater for more negative PSA terms. CONCLUSIONS: The amount and direction of PSA and SSA terms, as measured with different MFCLs on eye, can affect VP at different distances. Results of this study may provide useful information when designing new or optimize existing MFCLs for improved VP at specific distances.


Assuntos
Lentes de Contato Hidrofílicas , Presbiopia/terapia , Acuidade Visual/fisiologia , Aberrometria , Adulto , Estudos Cross-Over , Feminino , Humanos , Iluminação , Masculino , Pessoa de Meia-Idade , Presbiopia/fisiopatologia , Estudos Prospectivos , Pupila/fisiologia
11.
Optom Vis Sci ; 93(4): 435-44, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26808384

RESUMO

PURPOSE: To compare the objective and subjective visual performance of a novel contact lens which extends depth of focus by deliberate manipulation of higher-order spherical aberrations and a commercially available zonal-refractive multifocal lens. METHODS: A prospective, cross-over, randomized, single-masked, short-term clinical trial comprising 41 presbyopes (age 45 to 70 years) wearing novel Extended Depth of Focus lenses (EDOF) and ACUVUE OAYS for Presbyopia (AOP). Each design was assessed on different days with a minimum overnight wash-out. Objective measures comprised high-contrast visual acuity (HCVA, logMAR) at 6 m, 70 cm, 50 cm, and 40 cm; low-contrast visual acuity (LCVA, logMAR) and contrast sensitivity (log units) at 6 m; and stereopsis (seconds of arc) at 40 cm. HCVA at 70 cm, 50 cm, and 40 cm were measured as "comfortable acuity" rather than conventional resolution acuity. Subjective performance was assessed on a 1-10 numeric rating scale for clarity of vision and ghosting at distance, intermediate and near, overall vision satisfaction, ocular comfort, and lens purchase. Statistical analysis included repeated measures ANOVA and paired t tests. RESULTS: HCVA, clarity of vision, and ghosting with EDOF were significantly better than AOP (p < 0.01); however, differences were dependent on testing distances and add groups. Post hoc analysis showed EDOF was significantly better than AOP for HCVA at 70 cm (0.11 ± 0.11 vs. 0.21 ± 0.16, p < 0.001), 50 cm (0.26 ± 0.17 vs. 0.36 ± 0.18, p = 0.003), 40 cm (0.42 ± 0.17 vs. 0.52 ± 0.21, p = 0.001), and LCVA at 6 m (0.22 ± 0.08 vs. 0.27 ± 0.12, p = 0.024). EDOF was significantly better than AOP for clarity of vision at distance (7.7 ± 1.6 vs. 6.8 ± 2.3, p = 0.029), intermediate (8.8 ± 1.4 vs. 7.0 ± 2.2, p < 0.001), and near (7.4 ± 2.4 vs. 5.2 ± 2.7, p < 0.001), ghosting at distance (9.1 ± 1.2 vs. 8.1 ± 2.5, p = 0.005), and overall vision satisfaction (7.6 ± 1.6 vs. 6.0 ± 2.6, p < 0.001). More participants chose to purchase EDOF compared to AOP (61 vs. 39%) and significantly more chose to only-purchase EDOF compared to only-purchase AOP (27 vs. 5%, p = 0.022). CONCLUSIONS: When compared with AOP, EDOF lenses provide better intermediate and near vision performance in presbyopic participants without compromising distance vision.


Assuntos
Lentes de Contato Hidrofílicas , Percepção de Profundidade/fisiologia , Presbiopia/terapia , Idoso , Sensibilidades de Contraste/fisiologia , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Presbiopia/fisiopatologia , Estudos Prospectivos , Desenho de Prótese , Método Simples-Cego , Acuidade Visual/fisiologia
12.
Gut ; 62(11): 1602-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22580415

RESUMO

OBJECTIVE: In a previous study, the authors have shown that rather than variants in trypsinogen gene(s), mutations in pancreatic secretory trypsin inhibitor (encoded by SPINK1) and cathepsin B (CTSB) are associated with tropical calcific pancreatitis (TCP). Recently, chymotrypsin C (CTRC) variants that diminish its activity or secretion were found to predict susceptibility to chronic pancreatitis (CP). The authors analysed CTRC variants in a large, ethnically matched case-control TCP cohort. DESIGN: The authors sequenced all eight exons and flanking regions in CTRC in 584 CP patients (497 TCP, 87 idiopathic CP) and 598 normal subjects and analysed the significance of association using χ(2) test. The authors also investigated interaction of CTRC variants with p.N34S SPINK1 and p.L26V CTSB mutations. RESULTS: The authors identified 14 variants in CTRC, of which non-synonymous variants were detected in 71/584 CP patients (12.2%) and 22/598 controls (3.7%; OR 3.62, 95% CI 2.21 to 5.93; p=6.2 × 10(-8)). Rather than the commonly reported p.K247_R254del variant in Caucasians, p.V235I was the most common mutation in Indian CP patients (28/575 (4.9%); OR 7.60, 95% CI 2.52 to 25.71; p=1.01 × 10(-5)). Another pathogenic variant, p.A73T was identified in 3.1% (18/584) patients compared with 0.3% (2/598) in controls (OR=9.48, 95% CI 2.19 to 41.03, p=2.5 × 10(-4)). The authors also observed significant association for the synonymous variant c.180C>T (p.(=)) with CP (OR 2.71, 95% CI 1.79 to 4.12, p=5.3 × 10(-7)). Two novel nonsense mutations, p.G242AfsX9 and p.W113X were also identified exclusively in CP patients. No interaction between CTRC variants and p.N34S SPINK1 or p.L26V CTSB mutations was observed. CONCLUSION: This study on a large cohort of TCP patients provides evidence of allelic heterogeneity and confirms that CTRC variants play a significant role in its pathogenesis.


Assuntos
Calcinose/genética , Quimotripsina/genética , Mutação , Pancreatite Crônica/congênito , Calcinose/enzimologia , Proteínas de Transporte/genética , Estudos de Casos e Controles , Catepsina B/genética , Predisposição Genética para Doença , Genótipo , Humanos , Pancreatite Crônica/enzimologia , Pancreatite Crônica/genética , Inibidor da Tripsina Pancreática de Kazal
13.
Phytopathology ; 103(9): 935-40, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23758293

RESUMO

The root-knot nematode Meloidogyne hapla can reproduce on a wide range of crop species but there is variability in host range and pathogenicity both within and between isolates. The inbred strain VW9 causes galling but does not reproduce on Solanum bulbocastanum clone SB22 whereas strain VW8 causes little galling and reproduces poorly on this host. Comparison of reproduction on SB22 of nematode F2 lines generated from hybrids between strains VW8 and VW9 revealed that, whereas over half the lines produced no progeny, some lines reproduced to higher levels than did either parental strain. Using a genetic map previously generated using the same set of F2 lines, three quantitative trait loci (QTLs) were identified and positioned on linkage groups. A combination of two QTL alleles from one parent and one from the other was highly represented in F2 lines that exhibited higher reproduction than either parental strain but was absent from lines that failed to reproduce on SB22. This result suggests that sexual hybridization and assortment of opposing alleles leads to segregation of individuals with improved reproductive ability on a particular host. The genome sequence and integrated genetic and physical linkage map of M. hapla provide resources for identification of genes responsible for the identified QTL.


Assuntos
Genoma/genética , Doenças das Plantas/parasitologia , Locos de Características Quantitativas/genética , Solanum/parasitologia , Tylenchoidea/genética , Alelos , Animais , Mapeamento Cromossômico , Feminino , Loci Gênicos , Contagem de Ovos de Parasitas , Fenótipo , Raízes de Plantas/parasitologia , Especificidade da Espécie , Tylenchoidea/crescimento & desenvolvimento , Tylenchoidea/patogenicidade , Tylenchoidea/fisiologia
14.
J Ayurveda Integr Med ; 14(4): 100744, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37422989

RESUMO

Diabetes mellitus is a growing concern all over the world. There are no many published literature available documenting the effectiveness of Ayurveda intervention on diabetes mellitus. This report is about a case in which successful reversal of diabetes mellitus was achieved in a patient who reported with glycosylated Hb percentage (HbA1C) as high as 14.87%. The patient had classical symptoms of diabetes mellitus viz. excessive thirst, fatigue and frequent urination. His fasting blood glucose level was 346 mg/dl and post prandial glucose level of 511 mg/dl. Further more his HbA1C was as high as 14.87%, thus diagnosed with diabetes mellitus. Based on his specific clinical symptoms the patient was diagnosed with kaphaja prameha. Treatment was given according to classical Ayurveda intervention for kaphaja prameha. The patient responded well to the treatment. His HbA1C reduced to 6.05% in a span of eight months. The case report shows the effectiveness of Ayurvedic intervention in diabetes mellitus. It is limited in its scope as it is a case report, nevertheless this can be taken up as an information that may lead to new research and advances in the field of clinical practice in Ayurveda.

15.
Ann Gastroenterol ; 36(6): 678-685, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023969

RESUMO

Background: Left ventricular diastolic dysfunction (LVDD) is an early manifestation of cirrhotic cardiomyopathy. Few studies have addressed its clinical significance in cirrhosis. We assessed the association of LVDD with the factors affecting cirrhosis patients' severity, complications, and survival. Methods: A total of 203 cirrhosis patients were enrolled and underwent investigations, including 2-dimensional echocardiography with tissue Doppler imaging, and 139 patients with LVDD (cases) were compared with 64 patients without LVDD (controls). Logistic regression and Kaplan-Meier analysis were applied. Results: Mean age was 52.76±10 years. Among LVDD patients, 56% had grade-1, and 44% had grade-2 LVDD. Cirrhosis related to NASH had a more significant association with LVDD (P<0.001) than other etiologies. LVDD was significantly associated with a greater incidence of Child-Turcotte-Pugh (CTP) class C (P<0.001), higher model for end-stage liver disease scores (P=0.001), duration of cirrhosis >2 years since diagnosis (P=0.028), ascites (P<0.001), hepatic encephalopathy (P<0.010), hepatorenal syndrome (P<0.001), and a history of obesity (P=0.004). Multivariate analysis showed that higher CTP score, ascitic fluid protein and prolonged QTc interval were independently associated with LVDD (P=0.009; P=0.018; P=0.016, respectively). Kaplan-Meier survival analysis showed significantly poorer survival status in patients with higher grades of LVDD (P<0.001). The area under the receiver operating characteristic curve (0.78) was greatest for ascitic fluid protein in predicting LVDD, with a cutoff of >1 g/dL. Conclusions: Higher CTP score, prolonged QTc, higher ascitic fluid protein levels, and poor survival are significantly associated with LVDD. Ascitic fluid protein >1 g/dL could be an indicator for evaluating LVDD.

16.
Optom Vis Sci ; 89(12): 1674-81, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23160441

RESUMO

PURPOSE: Compared with daily disposable wear schedule, continuous wear (CW) or extended wear of contact lenses has been associated with an increased risk of developing an ocular infection. Proof-of-principle studies were conducted to investigate the impact of daily replacement of lenses on the rate of contact lens-related ocular adverse events (AEs) during 30-night CW. METHODS: A total of 215 subjects were dispensed with silicone hydrogel lenses on a 30-night CW schedule but replaced lenses daily either each night before sleeping (n = 178 eyes) or each morning after waking (n = 252 eyes). Scheduled clinic visits were conducted at 1 week and 1 month. Neophytes were required to complete 1 week of daily wear before commencing CW. A historical control (n = 191 eyes) using the same site, subject demographics, and visit schedule but monthly lens replacement was used for AE rates. RESULTS: Logistic regression analysis showed a significant reduction in mechanical AEs (0.8 vs 5.2%, p = 0.01) and overall AEs (inflammatory and mechanical events) (4.0 vs 8.9%, p = 0.04) when lenses were replaced each morning compared with being replaced monthly. Estimation of handling-related lens contamination of unworn lenses in a subgroup of subjects showed isolation of Staphylococcus aureus from the lenses of 35% of subjects, and 65% of subjects had more than 1000 colony-forming units per lens of gram-positive bacterial contamination. CONCLUSIONS: Morning lens replacement during CW reduced mechanical and overall ocular AEs. Replacing lenses at night had no beneficial effects perhaps because the benefit of a fresh lens at night might be partially negated by contamination of the contact lens caused by lens handling before overnight eye closure. Contact lens wearers on an extended wear or CW schedule should be advised to minimize lens handling before sleep to reduce the risk of complications.


Assuntos
Lentes de Contato de Uso Prolongado/efeitos adversos , Lentes de Contato de Uso Prolongado/microbiologia , Equipamentos Descartáveis , Infecções Oculares Bacterianas/epidemiologia , Staphylococcus aureus/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Infecções Oculares Bacterianas/etiologia , Infecções Oculares Bacterianas/prevenção & controle , Feminino , Seguimentos , Humanos , Incidência , Índia/epidemiologia , Masculino , Estudos Retrospectivos , Adulto Jovem
17.
Optom Vis Sci ; 89(8): 1196-202, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22797511

RESUMO

PURPOSE: To characterize seasonal variation in the myopic progression of Chinese children. METHODS: Myopia progression data are presented for a total of 85 Chinese children, aged 6 to 12 years, with baseline myopia of -0.75 D to -3.50 D sphere and astigmatism ≤-1.50 D, who wore traditional single-vision spectacles in two clinical trials (trial A: n = 37, trial B: n = 48). Refractive error and axial length data were obtained at 6-month intervals using cycloplegic autorefraction and partial coherence interferometry, respectively. Progression rates for right eyes were defined for the first and second 6 months of the studies and classified in terms of "summer," "autumn," "winter," or "spring" based on the mid-point of the 6-month period between visits. RESULTS: The mean 6-month spherical equivalent progression was -0.31 ± 0.25 D for summer, -0.40 ± 0.27 D for autumn, -0.53 ± 0.29 D for winter, and -0.42 ± 0.20 D for spring (p < 0.001). Mean axial elongation was 0.17 ± 0.10 mm for summer, 0.24 ± 0.09 mm for autumn, 0.24 ± 0.09 mm for winter, and 0.15 ± 0.08 mm for spring (p < 0.001). Post hoc analysis indicated that data for summer and winter were different from each other at p < 0.05 for both myopia progression and axial elongation after adjusting for age. CONCLUSIONS: Myopia progression in summer months was approximately 60% of that seen in winter, and axial elongation was likewise significantly less in summer. It is unclear whether more time spent outdoors in summer vs. winter is a contributing factor, or the difference in progression rates is a result of "seasonal" variations in the intensity or amount of close work performed. These results indicate that studies of potential myopia treatment strategies should be at least 12 months in duration to take seasonal variations into account.


Assuntos
Miopia Degenerativa/diagnóstico , Refração Ocular/fisiologia , Estações do Ano , Criança , China/epidemiologia , Progressão da Doença , Óculos , Feminino , Seguimentos , Humanos , Masculino , Miopia Degenerativa/epidemiologia , Miopia Degenerativa/terapia , Prognóstico , Estudos Retrospectivos
18.
Indian J Surg Oncol ; 13(1): 51-60, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35462653

RESUMO

Involvement of the aerodigestive tract is reported in one-third of patients with locally invasive thyroid cancer. It is associated with significant morbidity and mortality, with airway obstruction being the immediate cause of death in 50% of patients who die of thyroid cancer. Management is challenging and includes the risks of extensive surgery as well as decisions regarding the type of surgery and adjuvant therapy. Retrospective cohort study, reporting institutional experience with patients who underwent laryngotracheal resection for invasive thyroid cancer over the past 10 years. Twenty-two patients were included in the study. All patients had Shin stage 4 disease. The median follow-up was 18 months. Five patients had systemic metastasis at diagnosis. Nineteen patients underwent tracheal resection and end to end anastomosis, and 3 underwent laryngectomy. The mean length of the resected trachea was 2.94 cm. Tracheal releasing manoeuvres were utilized in 11 patients. Three patients required a tracheostomy postoperatively. Other complications included a temporary vocal cord palsy in 5 patients, temporary hypocalcemia in 6 and permanent hypocalcemia in 1 patient. Adjuvant radiotherapy was utilized in 9 patients and I-131 therapy in 13 patients. Three patients died during follow-up. Two patients developed thyroid bed recurrence, two patients developed systemic metastasis on follow-up. Most patients survived for a prolonged period with only biochemical evidence of disease persistence and three with no evidence of disease. Laryngotracheal resection with primary anastomosis is a safe and effective option, providing adequate symptomatic relief as well as prolonged survival in carefully selected patients with invasive Shin stage 4 disease.

19.
Updates Surg ; 74(1): 97-105, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34727341

RESUMO

We conducted this study to evaluate the ability of indocyanine green (ICG) and near infra-red fluorescence (NIRF) camera to aid in the identification and assessment of viability of parathyroid glands during thyroid surgery. A prospective observational study was conducted between May and October 2020 among 50 consecutive patients who underwent total thyroidectomy at a single institution. Parathyroid glands were identified under white light during thyroidectomy following which reconstituted ICG was injected through a peripheral vein and the location of parathyroid glands was confirmed. The perfusion to the parathyroid gland was assessed by documenting the fluorescence intensity score (FIS) and the parathyroid angiogram score (PAS). There was no difference in the number of parathyroid glands seen on visual inspection 147 (73.5%) when compared to under NIRF camera, 146 (73%). Though the rate of postoperative hypoparathyroidism was lower in the cohort with FIS 3 (14.2%) compared to score 2 and 1 (28.5% and 100%, respectively), this was not significant (p = 0.35). A significant correlation was noted between a delayed flow on PAS and the development of post-thyroidectomy hypoparathyroidism (p = 0.01). PAS had a sensitivity of 100%, specificity of 88.6%, NPV of 100% and PPV of 55.6% to predict the development of post-thyroidectomy hypoparathyroidism. In this study, there was no additional benefit of ICG and NIRF camera in the identification of parathyroid glands. However, ICG angiogram seems to be a good adjunct for the intraoperative assessment of the viability of the parathyroid glands and accurately predicts the development of postoperative hypoparathyroidism.


Assuntos
Hipoparatireoidismo , Glândulas Paratireoides , Humanos , Hipoparatireoidismo/diagnóstico , Hipoparatireoidismo/etiologia , Verde de Indocianina , Glândulas Paratireoides/diagnóstico por imagem , Glândulas Paratireoides/cirurgia , Complicações Pós-Operatórias , Glândula Tireoide , Tireoidectomia
20.
Proc Natl Acad Sci U S A ; 105(39): 14802-7, 2008 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-18809916

RESUMO

We have established Meloidogyne hapla as a tractable model plant-parasitic nematode amenable to forward and reverse genetics, and we present a complete genome sequence. At 54 Mbp, M. hapla represents not only the smallest nematode genome yet completed, but also the smallest metazoan, and defines a platform to elucidate mechanisms of parasitism by what is the largest uncontrolled group of plant pathogens worldwide. The M. hapla genome encodes significantly fewer genes than does the free-living nematode Caenorhabditis elegans (most notably through a reduction of odorant receptors and other gene families), yet it has acquired horizontally from other kingdoms numerous genes suspected to be involved in adaptations to parasitism. In some cases, amplification and tandem duplication have occurred with genes suspected of being acquired horizontally and involved in parasitism of plants. Although M. hapla and C. elegans diverged >500 million years ago, many developmental and biochemical pathways, including those for dauer formation and RNAi, are conserved. Although overall genome organization is not conserved, there are areas of microsynteny that may suggest a primary biological function in nematodes for those genes in these areas. This sequence and map represent a wealth of biological information on both the nature of nematode parasitism of plants and its evolution.


Assuntos
Genoma Helmíntico , Interações Hospedeiro-Parasita/genética , Plantas/parasitologia , Tylenchoidea/genética , Animais , Sequência de Bases , Caenorhabditis elegans/genética , Mapeamento Cromossômico , Evolução Molecular , Duplicação Gênica , Transferência Genética Horizontal , Dados de Sequência Molecular , Família Multigênica , Óperon , Filogenia , Sintenia
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