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1.
J Anim Ecol ; 93(1): 57-70, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37975479

RESUMO

The island species-area relationship (ISAR) describes how species richness increases with increasing area of a given island or island-like habitat, such as freshwater lakes. While the ISAR is one of the most common phenomena observed in ecology, there is variation in both the form of the relationship and its underlying mechanisms. We compiled a global data set of benthic macroinvertebrates from 524 shallow freshwater lakes, ranging from 1 to 293,300 ha in area. We used individual-based rarefaction to determine the degree to which ISAR was influenced by mechanisms other than passive sampling (larger islands passively sample more individuals from the regional pool and, therefore, have more species than smaller islands), which would bias results away from expected relationships between rarefied species richness (and other measures that capture relative abundances) and lake area. We also examined how climate may alter the shape of the ISARs. We found that both rarefied species richness (the number of species standardized by area or number of individuals) and a measure of evenness emphasizing common species exhibit shallow slopes in relationships with lake area, suggesting that the expected ISARs in these lakes most likely result from passive sampling. While there was considerable variation among ISARs across the investigated lakes, we found an overall positive rarefied ISAR for lakes in warm (i.e. tropical/subtropical) regions (n = 195), and in contrast, an overall negative rarefied ISAR in cool (i.e. north temperate) lakes (n = 329). This suggested that mechanisms beyond passive sampling (e.g. colonization-extinction dynamics and/or heterogeneity) were more likely to operate in warm lakes. One possible reason for this difference is that the area-dependent intensity of fish predation, which can lead to flatter ISARs, is weaker in warmer relative to cooler lakes. Our study illustrates the importance of understanding both the pattern and potential processes underlying the ISARs of freshwater lakes in different climatic regions. Furthermore, it provides a baseline for understanding how further changes to the ecosystem (i.e. in lake area or climate) might influence biodiversity patterns.


Assuntos
Biodiversidade , Ecossistema , Animais , Lagos , Peixes , Ecologia
2.
Exp Eye Res ; 202: 108356, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33197452

RESUMO

The inflammatory process plays a crucial role in frailty syndrome, which can appear in middle age and is associated with a poor health outcome. Consequently, gerontologists recommend screening inflammatory biomarkers in middle-aged adults to detect frailty and, therefore, prevent chronic diseases and mortality. External factors could be a risk factor for frailty because they can generate and extend the inflammatory process. For these reasons, we analysed the effect of long-term contact lens wear on mRNA level of genes linked to inflammation (IL-6, NLRP3, NK1R, CD73, MUC16 and TRPV1 genes) in conjunctival cells of middle-aged individuals, by quantitative PCR. Middle-aged contact lens wearers presented a significant increase of NLRP3 and MUC16 mRNA level as well as a decrease of CD73 mRNA level, in comparison with non-contact lens wearers. Additionally, we checked for a potential correlation between these transcript levels and clinical changes of the participants' ocular surface. Unlike molecular analysis, clinical examination fails to detect inflammation in contact lens wearers. These data suggest that long-term contact lens wear could trigger an inflammatory response in middle age orchestrated by NLRP3 inflammasome and modulated by CD73 and MUC16 proteins. Further studies are needed to confirm our gene expression findings at the protein level as well as to investigate the potential role of long-term CL wear in the onset of ocular frailty.


Assuntos
Túnica Conjuntiva/metabolismo , Lentes de Contato Hidrofílicas , Idoso Fragilizado , Fragilidade/genética , Regulação da Expressão Gênica , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Idoso , Fragilidade/metabolismo , Humanos , Pessoa de Meia-Idade , Proteína 3 que Contém Domínio de Pirina da Família NLR/biossíntese
3.
Eye Contact Lens ; 47(4): 213-218, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33323876

RESUMO

OBJECTIVE: The objective of this study was to assess the impact of 0.50 diopter (D) positive or negative defocus on visual function in patients implanted with trifocal and trifocal toric intraocular lenses (IOLs). METHODS: The study included patients implanted with the AcrySof IQ PanOptix IOL or the PanOptix Toric. Visual acuity (VA) at high (100%), medium (50%) and low (10%) contrast, contrast sensitivity function (CSF), and halo perception were assessed three months after surgery. Explorations were performed with corrected distance visual acuity (CDVA), with a positive defocus of +0.50D (myopization) and with a negative defocus of -0.50D (hyperopization). RESULTS: The study included 60 eyes of 60 patients (30 eyes with PanOptix and 30 eyes with PanOptix Toric). For both groups, VA was better for all contrast settings at the CDVA situation (P<0.05 in all cases). For low spatial frequencies, no differences in CSF were found among the three refractive situations in either group. For higher frequencies, the results showed an overall trend for better CSF results for the CDVA situation. The halo effect was lower for the CDVA situation if compared to myopization and hyperopization in both the PanOptix and the PanOptix Toric groups (P<0.05 for all cases). CONCLUSIONS: There is an impact on visual quality and halo perception in patients implanted with trifocal or trifocal toric IOLs even for low residual refractive errors.


Assuntos
Lentes Intraoculares , Facoemulsificação , Erros de Refração , Humanos , Implante de Lente Intraocular , Satisfação do Paciente , Estudos Prospectivos , Desenho de Prótese , Refração Ocular , Erros de Refração/terapia
4.
Optom Vis Sci ; 95(6): 523-535, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29787486

RESUMO

SIGNIFICANCE: Currently, treatments for amblyopia are occlusion or penalization of the stronger fellow eye. Fewer than 30% of patients improve stereoacuity using these treatments. In order to improve these outcomes, this group proposes a treatment to stimulate the stereoacuity through perceptual learning in a game format for use at home. PURPOSE: The aim of this study was to determine whether perceptual learning with random dot stimuli (RDS) in the form of a computer video game improves stereopsis in patients with a history of amblyopia. METHODS: Thirty-two stereo-deficient patients (7 to 14 years old) previously treated for amblyopia participated in a prospective, randomized, double-blind study. Participants followed a perceptual learning program at home using RDS software. In the experimental group, the demand of stereopsis was increased, until reaching the lowest detectable disparity. In the comparison group, the stimulation interval was a constant (840 to 750"). Stereoacuity was evaluated with the Randot Preschool Stereoacuity Test (RPST) and the Wirt Circles. RESULTS: Median compliance was 100% (interquartile range [IQR] = 78.50 to 100). Log10 stereoacuity outcomes were significantly different between groups (RPST, P = .041; Wirt Circles Test, P = .009). Median stereoacuity improvement with RPST was 50% (IQR = 0.00 to 75%) and 0% (IQR = 0.00 to 7.5%), respectively, for experimental and comparison groups (P = .008). Wirt Circles improvement was 46.42% (IQR = 6.25 to 73.75%) and 0% (IQR = 0.00 to 57.50%), respectively, for experimental and comparison groups (P = .089). Stereoacuity improvement was not different between groups when success was considered a 70% gain in RPST (P = .113); it was statistically different when success was considered a gain of two levels on Wirt Circles and stereoacuity 140" or less (P = .023). Stereoacuity remained stable after 6 months when measured with RPST, whereas it worsened in two subjects when measured with Wirt Circles. CONCLUSIONS: Direct stimulation of stereopsis at home using RDS in a game environment improves the stereoacuity in stereo-deficient subjects with a history of amblyopia.


Assuntos
Ambliopia/terapia , Percepção de Profundidade/fisiologia , Jogos de Vídeo , Adolescente , Ambliopia/fisiopatologia , Biometria , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Cooperação do Paciente , Estudos Prospectivos , Testes Visuais , Visão Binocular/fisiologia , Acuidade Visual/fisiologia
5.
Microb Ecol ; 73(2): 296-309, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27726035

RESUMO

Microbes can modulate ecosystem function since they harbor a vast genetic potential for biogeochemical cycling. The spatial and temporal dynamics of this genetic diversity should be acknowledged to establish a link between ecosystem function and community structure. In this study, we analyzed the genetic diversity of bacterial phosphorus utilization genes in two microbial assemblages, microbialites and bacterioplankton of Lake Alchichica, a semiclosed (i.e., endorheic) system with marked seasonality that varies in nutrient conditions, temperature, dissolved oxygen, and water column stability. We focused on dissolved organic phosphorus (DOP) utilization gene dynamics during contrasting mixing and stratification periods. Bacterial alkaline phosphatases (phoX and phoD) and alkaline beta-propeller phytases (bpp) were surveyed. DOP utilization genes showed different dynamics evidenced by a marked change within an intra-annual period and a differential circadian pattern of expression. Although Lake Alchichica is a semiclosed system, this dynamic turnover of phylotypes (from lake circulation to stratification) points to a different potential of DOP utilization by the microbial communities within periods. DOP utilization gene dynamics was different among genetic markers and among assemblages (microbialite vs. bacterioplankton). As estimated by the system's P mass balance, P inputs and outputs were similar in magnitude (difference was <10 %). A theoretical estimation of water column P monoesters was used to calculate the potential P fraction that can be remineralized on an annual basis. Overall, bacterial groups including Proteobacteria (Alpha and Gamma) and Bacteroidetes seem to be key participants in DOP utilization responses.


Assuntos
Bactérias/genética , Genes Bacterianos/genética , Variação Genética , Lagos/microbiologia , Fósforo/metabolismo , Filogenia , Fosfatase Alcalina/genética , Organismos Aquáticos/genética , Organismos Aquáticos/metabolismo , Bactérias/enzimologia , Bactérias/metabolismo , Bacteroidetes/genética , Bacteroidetes/metabolismo , Sequência de Bases , DNA Bacteriano/análise , Ecossistema , Meio Ambiente , Regulação Bacteriana da Expressão Gênica , Marcadores Genéticos/genética , México , Oxigênio/química , Fósforo/química , Compostos de Fósforo/química , Compostos de Fósforo/metabolismo , Reação em Cadeia da Polimerase/métodos , Proteobactérias/genética , Proteobactérias/metabolismo , RNA Bacteriano/análise , Estações do Ano , Análise de Sequência , Água/química
6.
Rev Biol Trop ; 64(4): 1469-86, 2016 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-29465910

RESUMO

The diversity of chondrychthyans in Mexico is described. The fauna is composed by 214 species (111 sharks, 95 rays and 8 chimaeras) and represents 17.3 % of the total number of species recorded worldwide. The families with the highest diversity comprise: Rajidae (14.5 %), Carcharhinidae (12.1 %), Pentanchidae, Triakidae, and Urotrygonidae (5.1 %). In terms of geographical distribution, the diversity on the Mexican Pacific slope reaches up to 56.1 % of those species inhabiting Mexican marine and brackish waters (120 species, 62 genera, 37 families and 14 orders); the diversity in the Atlantic slope resulted similar to that on the Mexican Pacific with 55.1 % of the species (118 species, 59 genera, 35 families and 13 orders). The biogeographical affinities of the Mexican chondrychthyan fauna are complex with 19.7 % of the species being circumglobal, 9.9 % transatlantic, 1.9 % transpacific, and 9.4 % endemic to the exclusive economic zone. Additionally, 36.6 % of the species recorded so far are endemic to the Eastern Pacific coast where the species are similar to those found in the Cortez biogeographic province (27.7 %), followed by the Californian (20.7 %), Panamanian (19.3 %), Galapagos (5.6 %) and Peruvian-Chilean (8.9 %). Likewise, 33.3 % are endemic of the Atlantic coast, where species are similar to those found in the Caribbean province (31.9 %), followed by the Carolinean (24.4 %) and the Brazilian (6.6 %).


Assuntos
Distribuição Animal , Biodiversidade , Cordados/classificação , Tubarões/classificação , Rajidae/classificação , Animais , Oceano Atlântico , Cordados/fisiologia , México , Oceano Pacífico , Tubarões/fisiologia , Rajidae/fisiologia , Especificidade da Espécie
7.
Clin Exp Ophthalmol ; 42(3): 271-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23927051

RESUMO

BACKGROUND: To compare the in vitro optical quality of two new trifocal intraocular lenses at different focal points as a function of pupil size. METHODS: Two intraocular lenses having different design approaches were evaluated: the AT LISA tri 839MP with a trifocal diffractive design, and the FineVision, which combines two distinct apodized bifocal diffractive profiles resulting in three foci. A PMTF optical bench was used to assess the intraocular lenses' performance, and as optical quality metrics, the through-focus modulation transfer function was selected; that is, it was measured at 10 focal points and for four different apertures (2.0, 3.0, 3.75 and 4.5 mm). RESULTS: For both lenses, the through-focus curve showed three peaks, corresponding to far, intermediate and near focal point. At the 0.0 D focal point, the FineVision yielded better results for larger pupils. At the -1.5 D focal point, both lenses performed worse for larger pupils. At the -3.0 D, the FineVision provided better results for all apertures. However, at the -3.5 D focal point, it was the AT LISA tri 839MP that outperformed the FineVision for larger pupils. CONCLUSIONS: The two trifocal intraocular lenses under analysis have modulation transfer function peaks that correspond to the far, intermediate and near focal points. For larger pupil sizes, the FineVision seems to provide better results at far focal points, while the AT LISA tri 839MP not only provides better results at the intermediate and near focal points, but is also less pupil size-dependent.


Assuntos
Lentes Intraoculares , Óptica e Fotônica , Pupila/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Modelos Teóricos , Desenho de Prótese
8.
PeerJ ; 12: e17393, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38799067

RESUMO

Inland waters are crucial in the carbon cycle, contributing significantly to the global CO2 fluxes. Carbonate lakes may act as both sources and sinks of CO2 depending on the interactions between the amount of dissolved inorganic carbon (DIC) inputs, lake metabolisms, and geochemical processes. It is often difficult to distinguish the dominant mechanisms driving CO2 dynamics and their effects on CO2 emissions. This study was undertaken in three groundwater-fed carbonate-rich lakes in central Spain (Ruidera Lakes), severely polluted with nitrates from agricultural overfertilization. Diel and seasonal (summer and winter) changes in CO2 concentration (CCO2) DIC, and CO2 emissions-(FCO2)-, as well as physical and chemical variables, including primary production and phytoplanktonic chlorophyll-a were measured. In addition, δ13C-DIC, δ13C-CO2 in lake waters, and δ13C of the sedimentary organic matter were measured seasonally to identify the primary CO2 sources and processes. While the lakes were consistently CCO2 supersaturated and FCO2 was released to the atmosphere during both seasons, the highest CCO2 and DIC were in summer (0.36-2.26 µmol L-1). Our results support a strong phosphorus limitation for primary production in these lakes, which impinges on CO2 dynamics. External DIC inputs to the lake waters primarily drive the CCO2 and, therefore, the FCO2. The δ13C-DIC signatures below -12‰  confirmed the primary geogenic influence on DIC. As also suggested by the high values on the calcite saturation index, the Miller-Tans plot revealed that the CO2 source in the lakes was close to the signature provided by the fractionation of δ13C-CO2 from calcite precipitation. Therefore, the main contribution behind the CCO2 values found in these karst lakes should be attributed to the calcite precipitation process, which is temperature-dependent according to the seasonal change observed in δ13C-DIC values. Finally, co-precipitation of phosphate with calcite could partly explain the observed low phytoplankton production in these lakes and the impact on the contribution to increasing greenhouse gas emissions. However, as eutrophication increases and the soluble reactive phosphorus (SRP) content increases, the co-precipitation of phosphate is expected to be progressively inhibited. These thresholds must be assessed to understand how the CO32- ions drive lake co-precipitation dynamics. Carbonate regions extend over 15% of the Earth's surface but seem essential in the CO2 dynamics at a global scale.


Assuntos
Dióxido de Carbono , Lagos , Estações do Ano , Lagos/química , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Espanha , Monitoramento Ambiental/métodos , Ciclo do Carbono , Fitoplâncton/metabolismo
9.
J Refract Surg ; 29(11): 749-54, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24203806

RESUMO

PURPOSE: To compare the in vitro optical quality at different focal points of two new bifocal intraocular lenses (IOLs) and one new trifocal IOL. METHODS: The AcrySof ReSTOR SV25T0 (+2.5 diopter [D] add) and the AcrySof ReSTOR SN6AD1 (+3.0 D add) with two main foci (Alcon Laboratories, Fort Worth, TX) and the AT LISA tri 839MP with three main foci (Carl Zeiss Meditec, Dublin, CA) were evaluated. The optical quality of the IOLs was measured with the PMTF optical bench (LAMBDA-X, Nivelles, Belgium). The optical quality of the IOLs was quantified by the modulation transfer function (MTF) at five different focal points (0.0, -1.5, -2.0, -2.5, and -3.0 D) and for 3.0- and 4.5-mm apertures. The through-focus MTF of the IOLs was also recorded. RESULTS: For the 0.0 D focal point, the AcrySof ReSTOR (+2.5 D add) obtained the highest MTF values for all apertures. For the -2.5 D focal point, the AcrySof ReSTOR (+3.0 D add) showed the highest MTF values for 3.0 mm. For the -3.0 D focal point at 3.0- and 4.5-mm aperture, the best values were obtained with the AcrySof ReSTOR (+3.0 D add) and the AT LISA, respectively. For the -1.5 D focal point, the trifocal IOL provided better values. For the -2.0 D focal point, all IOLs provided comparable results. The through-focus MTF curves showed three and two peaks for the trifocal and bifocal IOLs, respectively. CONCLUSIONS: The trifocal IOL provides a better optical quality at the -1.5 D focal point. However, the optical quality of the trifocal IOL significantly decreases compared to the bifocal IOLs at far distance and -2.5 D focal points.


Assuntos
Lentes Intraoculares , Óptica e Fotônica , Sensibilidades de Contraste , Desenho de Prótese , Acuidade Visual
10.
PLoS One ; 18(6): e0287066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37310987

RESUMO

High mountain lakes (HMLs) are considered unique and comparable ecosystems for monitoring global climate change. The food web structure can indicate the response of these ecosystems to ecological threats, such as fish introduction, by analyzing the trophic dynamics. Nonetheless, the food webs of tropical HMLs are less well-studied than temperate HMLs. The present study assessed the food webs of two neighboring (600 m apart) tropical HMLs, El Sol and La Luna, inside the crater of the Nevado de Toluca volcano, Mexico. It used stable isotopes (δ13C and δ15N) and Bayesian mixing models with different trophic discrimination factors and priors to assess the impacts of introduced rainbow trout, persisting only in the larger lake, El Sol. The food web in Lake El Sol was more complex than in Lake La Luna, mainly due to its larger size, extensive vegetated littoral zone, and being fueled by autochthonous primary production. In contrast, the smaller and fishless Lake La Luna has a reduced and bare littoral zone that harbored a simple food web substantially sustained by allochthonous carbon inputs. The persistence of introduced rainbow trout in Lake El Sol but not in Lake La Luna accentuated the differences between the lakes. The models suggested that rainbow trout fed on key consumers of littoral macroinvertebrates (70-80%) and pelagic zooplankton (20-30%), increasing the linkage between sub-networks. In both tropical HMLs, the species richness and herbivorous fraction were elevated compared with temperate HMLs, while the linkage density and omnivorous fraction were lower. Basal nodes dominated these tropical HMLs, and the vegetated littoral zone of Lake El Sol had more intermediate (omnivore) nodes. Our results showed the convenience of food web analysis to compare the effects of introduced fish in originally fishless lakes in different latitudes.


Assuntos
Cadeia Alimentar , Oncorhynchus mykiss , Animais , Ecossistema , Teorema de Bayes , Lagos , Carbono
11.
J Ophthalmol ; 2023: 7701390, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37180814

RESUMO

Background: To analyze the tolerance on distance vision of different combined residual astigmatic situations in patients implanted with a novel wavefront shaping extended depth of focus (EDoF) intraocular lens (IOL). Methods: The study included patients implanted with the Acrysof® IQ Vivity® IOL. Uncorrected (UDVA) and corrected distance visual acuity (CDVA) were measured three months after surgery, considering CDVA as the reference situation of the study. Distance VA was also measured in different refractive situations: (A) with 0.50 diopters (D) of positive (myopization) and negative (hyperopization) defocus and (B) with a residual mixed astigmatic refraction induced by adding a combination of -0.25 D spherical and 0.50 D cylindrical lenses placed in vertical (against the rule-ATR), oblique, and horizontal (with the rule-WTR) positions. Results: The study included 30 eyes of 30 patients. UDVA and CDVA were -0.04 ± 0.05 and -0.05 ± 0.05 logMAR, respectively. VA values with +0.50 D and -0.50 D of defocus were 0.01 ± 0.06 and 0.00 ± 0.04 logMAR, respectively. VA was better with distance correction (p < 0.001) and no differences were found between the myopic and the hyperopic situations (p=0.09). Distance VA for the ATR, oblique, and WTR astigmatic situations was 0.01 ± 0.05, 0.01 ± 0.06, and 0.01 ± 0.04 logMAR, respectively. VA was better for the reference situation (p < 0.001) and no differences were found among the three astigmatic situations (p=0.21). Conclusions: Low residual defocus and mixed astigmatic errors, regardless of its orientation, seem to be tolerated by patients implanted with the studied EDoF IOL. This trial is registered with NCT05392998. Registered 26 May 2022-Retrospectively registered.

12.
J Refract Surg ; 28(6): 406-12, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22692522

RESUMO

PURPOSE: To evaluate the depth of focus with monofocal intraocular lenses (IOLs) in patients with different corneal profiles using adaptive optics (AO) visual simulation. METHODS: An AO visual simulator (crx1, Imagine Eyes) was used to simulate the aberration pattern of three monofocal IOLs (Acrysof IQ SN60WF [Alcon Laboratories Inc]; Akreos Adapt AO [Bausch & Lomb]; and Triplato [AJL Ophthalmic]) of different optic designs. Five groups were considered: patients without any corneal refractive surgery (normal cornea group) and with prior low and high myopic and hyperopic ablations (low myopic ablation, high myopic ablation, low hyperopic ablation, and high hyperopic ablation groups). Defocus curves for all situations were measured, with the target being moved from -5.00 to +2.50 diopters (D) in 0.25-D steps, and visual acuity was measured at all vergences. RESULTS: Ten eyes from 10 patients were evaluated. The higher residual spherical aberration (SA) for all IOLs was obtained for the high myopic ablation group and the most negative residual SA was obtained for the high hyperopic ablation group. The best compromise between distance visual and depth of focus for the normal cornea, low myopic ablation, and high myopic ablation groups was obtained with the aspheric designs, whereas the best results for the low hyperopic and high hyperopic ablation groups were obtained with the spherical IOL. CONCLUSIONS: The results of this study suggest that the better compromise between distance visual acuity and depth of focus with the three IOLs and the different corneal profiles relies on a certain amount of positive SA. Above a certain limit of residual SA (positive or negative), visual acuity decreases at all vergences, worsening the depth of focus.


Assuntos
Aberrações de Frente de Onda da Córnea/fisiopatologia , Percepção de Profundidade/fisiologia , Lentes Intraoculares , Pseudofacia/fisiopatologia , Erros de Refração/fisiopatologia , Adulto , Córnea/fisiopatologia , Humanos , Implante de Lente Intraocular , Acuidade Visual/fisiologia , Adulto Jovem
13.
J Refract Surg ; 28(5): 327-34, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22421094

RESUMO

PURPOSE: To evaluate visual quality differences among intraocular lenses (IOLs) in patients with previous hyperopic laser ablations and to assess the impact of decentration and tilt of IOLs on visual quality. METHODS: An adaptive optics visual simulator was used to simulate the wavefront aberration pattern of one aberration-correcting IOL (AcrySof IQ SN60WF, Alcon Laboratories Inc) and two spherical IOLs with different amounts of positive spherical aberration (Akreos Adapt [Bausch & Lomb] and Triplato [AJL Ophthalmic]) in five situations-centered, 0.2 mm and 0.4 mm of decentration, and 2° and 4° of tilt-in two groups: simulated low hyperopic laser corneal ablation (low hyperopia group) and high hyperopic laser corneal ablation (high hyperopia group). Monocular distance visual acuity at 100%, 50%, and 10% contrast were measured. RESULTS: Ten eyes were evaluated. When the IOLs were centered, all IOLs obtained comparable results for the low hyperopia group, whereas for the high hyperopia group, the Akreos Adapt and AcrySof IQ SN60WF showed better visual acuity than the Triplato. When the IOLs were misaligned, for the low hyperopia group, the best visual acuity results were obtained with the Akreos Adapt and the most critical situation was at 0.4 mm of decentration. For the high hyperopia group, misalignments decreased visual acuity in a higher amount than for the low hyperopia group. CONCLUSIONS: Our results suggest that the IOLs studied offer good visual quality when they are centered for both groups. However, tilt and decentration of monofocal IOLs have an impact on visual function in patients with hyperopic ablations. For these patients, the Akreos Adapt is the most robust to misalignments.


Assuntos
Migração do Implante de Lente Intraocular/fisiopatologia , Aberrações de Frente de Onda da Córnea/fisiopatologia , Hiperopia/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ , Lasers de Excimer/uso terapêutico , Lentes Intraoculares , Complicações Pós-Operatórias , Adulto , Migração do Implante de Lente Intraocular/etiologia , Humanos , Refração Ocular/fisiologia , Acuidade Visual/fisiologia , Adulto Jovem
14.
Eye Contact Lens ; 38(5): 278-81, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22878381

RESUMO

PURPOSE: The aim of this study was to evaluate whether the creation of 2 foci (distance and near) provided by multizone refractive multifocal contact lenses (CLs) for presbyopia correction affects the measurements on Humphreys 24-2 Swedish interactive threshold algorithm (SITA) standard automated perimetry (SAP). METHODS: In this crossover study, 30 subjects were fitted in random order with either a multifocal CL or a monofocal CL. After 1 month, a Humphrey 24-2 SITA standard strategy was performed. The visual field global indices (the mean deviation [MD] and pattern standard deviation [PSD]), reliability indices, test duration, and number of depressed points deviating at P<5%, P<2%, P<1%, and P<0.5% on pattern deviation probability plots were determined and compared between multifocal and monofocal CLs. RESULTS: Thirty eyes of 30 subjects were included in this study. There were no statistically significant differences in reliability indices or test duration. There was a statistically significant reduction in the MD with the multifocal CL compared with monfocal CL (P=0.001). Differences were not found in PSD nor in the number of depressed points deviating at P<5%, P<2%, P<1%, and P<0.5% in the pattern deviation probability maps studied. CONCLUSIONS: The results of this study suggest that the multizone refractive lens produces a generalized depression in threshold sensitivity as measured by the Humphreys 24-2 SITA SAP.


Assuntos
Lentes de Contato , Presbiopia/fisiopatologia , Testes de Campo Visual/métodos , Campos Visuais/fisiologia , Algoritmos , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Presbiopia/terapia , Limiar Sensorial/fisiologia
15.
Eye Contact Lens ; 38(5): 288-94, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22878382

RESUMO

OBJECTIVE: The aim of this study was to evaluate ocular aberration changes through different simultaneous vision multifocal contact lenses (CLs). METHODS: Eighteen young-adult subjects with a mean age of 29.8±2.11 years took part. Changes in accommodative response, spherical aberration (C(4)(0)), horizontal coma (C(3)(1)), vertical coma (C(3)(-1)), and root mean square (RMS) of higher-order aberrations (HOAs, third to sixth orders) were evaluated. Measurements were obtained with a distance-single vision CL and 2 aspheric multifocal CLs of simultaneous focus center-near design (PureVision Low Add and PureVision High Add) for 2 accommodative stimuli (-2.50 and -4.00 D). All measurements were performed monocularly with a Hartmann-Shack aberrometer (IRX-3; Imagine Eyes, Orsay, France). RESULTS: No statistically significant differences were found in accommodative responses to -2.50- and -4.00-D stimuli between the single vision CL and the 2 multifocal CLs. Spherical aberration was found to decrease and become more negative with accommodation for both stimuli with all three CLs. Horizontal coma decreased significantly with accommodation (-2.5- and -4.00-D stimuli) for the distance-single vision CLs (P=0.002 and P=0.003). No differences were found in vertical coma Zernike coefficients. The RMS of HOAs was found to decrease only with the single vision CLs for both stimuli (P<0.01). CONCLUSIONS: Data obtained in this study suggest that in young subjects, the multifocal CLs studied do not induce large changes in accommodative response compared with the distance-single vision CLs. Spherical aberration reduced significantly with accommodation.


Assuntos
Acomodação Ocular/fisiologia , Lentes de Contato , Fenômenos Ópticos , Acuidade Visual/fisiologia , Adulto , Estudos Cross-Over , Feminino , Humanos , Masculino , Refração Ocular/fisiologia
16.
Sci Total Environ ; 852: 158521, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36067862

RESUMO

High mountain lakes and their catchments are remote ecosystems in areas with low anthropogenic disturbance. High mountain lakes integrate changes in the atmosphere and catchment areas (e.g., acid rain, airborne pollutants, climate change). The present research analyses long-term datasets of meteorological and limnological variables representing two tropical high mountain lakes, El Sol and La Luna, in Central Mexico to identify the impacts of anthropogenic disturbance (i.e., sentinels of global/climate change). The 54-year meteorological analysis showed marked interannual variability with no statistically significant air temperature or rainfall trends. However, from 2000 to 2018, the air temperature increased by 0.5 °C. Accordingly, the lake water temperature increased (Lake El Sol: 0.8 °C, Lake La Luna: 0.6 °C). Although the rainfall displayed no change, the water level decreased in both lakes (1.5 m), most likely associated with increased evapotranspiration. Unexpectedly, the dissolved inorganic nitrogen (DIN) concentration in the lakes decreased. The initial acid pH rose to close neutrality in Lake La Luna and to alkaline values in Lake El Sol. The latter may be a consequence of the lowered SOx and NOx emissions from governmental regulations promulgated to control atmospheric pollution beginning in 2000 and probably resulting in less acidic deposition. An additional explanation for the lakes' deacidification is the increased deposition of alkaline ions derived from activities at the volcano slopes. Since the atmospheric supply is the primary nitrogen source to high mountain lakes, the DIN concentration decline could reflect the reduction in atmospheric HNO3. Thus, Lakes El Sol and La Luna evidenced global change. Both lakes are inside the same crater and are subjected to similar influences; thus, they showed similar responses to global change (increasing lake water temperatures, declining water levels, higher pH value, and lower DIN concentrations). Nevertheless, their differences (e.g., catchment size, surface area, water volume, water depth, trophic status) influenced the magnitude of the impacts, with higher pH increases recorded in Lake El Sol and higher DIN concentrations in Lake La Luna.


Assuntos
Chuva Ácida , Poluentes Ambientais , Lagos , Ecossistema , Chuva Ácida/análise , México , Nitrogênio/análise , Água/análise , Poluentes Ambientais/análise , Monitoramento Ambiental/métodos
17.
PeerJ ; 10: e13999, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36132223

RESUMO

Eutrophication is a global problem causing the reduction of water quality and the loss of ecosystem goods and services. The lakes of the "Lagunas de Montebello" National Park (LMNP), Chiapas, Mexico, not only represent unique and beautiful natural scenic sites in southern Mexico but are also a national protected area and RAMSAR site. Unfortunately, some of these lakes started showing eutrophication signs since 2003. Anthropogenic activities (e.g., land-use change from forested to agricultural and urban development) are leading to water quality and trophic state alterations of the lakes of the LMNP. This study shows the results of a coupled limnological characterization and high-throughput sequencing of the V4 hypervariable region of the 16S rRNA gene to analyze the microbial composition of the water column in a set of oligotrophic and eutrophic lakes. Chlorophyll a (Chl-a) was the main environmental parameter correlated with the trophic conditions of the lakes. Although the microbial diversity was similar, the microbial composition changed significantly from oligo to eutrophic lakes. Proteobacteria, Firmicutes, and Cyanobacteria were the main components of oligotrophic lakes, and Cyanobacteria, Proteobacteria, and Bacteroidetes of eutrophic lakes. While Acinetobacter (Proteobacteria) and Cyanobium (a unicellular cyanobacterium) dominated in oligotrophic lakes, the filamentous, bloom-forming, and toxin-producing cyanobacteria Planktothrix was the dominant genus in eutrophic lakes. High-throughput sequencing allowed the detection of changes in the composition of the microbial component in oligotrophic lakes, suggesting a shift towards eutrophication, highlighting the relevance of sensitive monitoring protocols of these ecosystems to implement remediation programs for eutrophicated lakes and conservation strategies for those yet pristine.


Assuntos
Cianobactérias , Lagos , Lagos/análise , Ecossistema , Clorofila A , México , RNA Ribossômico 16S/genética , Parques Recreativos , Cianobactérias/genética
18.
Ageing Res Rev ; 74: 101553, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34971794

RESUMO

Age-related eye diseases, including dry eye, glaucoma, age-related macular degeneration, and diabetic retinopathy, represent a major global health issue based on their increasing prevalence and disabling action. Unraveling the molecular mechanisms underlying these diseases will provide novel opportunities to reduce the burden of age-related eye diseases and improve eye health, contributing to sustainable development goals achievement. The impairment of neutrophil extracellular traps formation/degradation processes seems to be one of these mechanisms. These traps formed by a meshwork of DNA and neutrophil cytosolic granule proteins may exacerbate the inflammatory response promoting chronic inflammation, a pivotal cause of age-related diseases. In this review, we describe current findings that suggest the role of neutrophils and their traps in the pathogenesis of the above-mentioned age-related eye diseases. Furthermore, we discuss why these cells and their constituents could be biomarkers and therapeutic targets for dry eye, glaucoma, age-related macular degeneration, and diabetic retinopathy. We also examine the therapeutic potential of some neutrophil function modulators and provide several recommendations for future research in age-related eye diseases.


Assuntos
Retinopatia Diabética , Armadilhas Extracelulares , Glaucoma , Biomarcadores , Retinopatia Diabética/terapia , Glaucoma/tratamento farmacológico , Humanos , Neutrófilos
19.
J Cataract Refract Surg ; 48(6): 679-684, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34508029

RESUMO

PURPOSE: To assess the effect on visual function of different residual astigmatic situations combined with 0.50 diopters (D) negative defocus at different distances in patients with trifocal intraocular lenses (IOLs). SETTING: Clínica Rementería, Madrid, Spain. DESIGN: Prospective case series. METHODS: The study included patients implanted with AcrySof IQ PanOptix IOL. Visual acuity (VA) was measured at far distance (0.00 D of vergence) and at -1.5 D, -2.5 D, and -3.0 D of vergence. Residual astigmatism was induced by adding 0.50 D and 1.00 D cylindrical lenses placed at 90 degrees (against the rule [ATR]), 45 degrees (oblique), and 180 degrees (with the rule). All measurements were made with distance correction (emmetropia as the reference situation) and with a simulated residual myopia of 0.50 D. RESULTS: The study included 61 eyes of 61 patients. Residual astigmatism of 0.50 D and 1.0 D was induced in 28 and 33 eyes, respectively. For both groups, distance and intermediate VAs were better for the reference situation (P < .001 for all cases). With 1.0 D of cylinder (without and with induced defocus), the proportion of patients who lost ≥2 lines was higher for the ATR astigmatism. For near vision, differences were smaller for all simulated situations. CONCLUSIONS: Residual astigmatism of up to 0.50 D, regardless of its orientation, seems to be tolerated at all distances. For astigmatisms of 1.0 D, distance and intermediate VAs decreased significantly, and ATR orientations showed worse results in a higher proportion of patients. The combination of astigmatism with residual myopia significantly decreased distance VA, whereas this negative shift affected near VA less.


Assuntos
Astigmatismo , Lentes Intraoculares , Miopia , Facoemulsificação , Astigmatismo/cirurgia , Humanos , Implante de Lente Intraocular/métodos , Facoemulsificação/métodos , Estudos Prospectivos , Desenho de Prótese , Refração Ocular
20.
Eur J Ophthalmol ; : 11206721221144928, 2022 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-36529873

RESUMO

BACKGROUND: To assess the visual quality and the tolerance to low refractive errors of two trifocal intraocular lenses (IOL) with different amounts of spherical aberration (SA). METHODS: The study included patients having bilateral implantation of the AcrySof® IQ PanOptixTM (aberration-correcting) or the RayOneTM (aberration-free) Trifocal IOL. Three months after the surgery patients underwent: monocular/binocular and uncorrected/corrected distance visual acuity (VA) and binocular defocus curves. Binocular contrast sensitivity (CSF) and subjective halo perception were assessed with the best distance correction (CDVA), with a positive defocus of + 0.50D and with a negative defocus of -0.50D. Patient's satisfaction was evaluated with the Catquest9-SF questionnaire. RESULTS: This study included 54 eyes (28 with PanOptix and 26 with RayOne) of 27 patients. Both groups achieved corrected/uncorrected and monocular/binocular distance VA values better than 0.0 logMAR (1.0 decimal) with no statistically significant differences between them (p > 0.05 for all cases). Defocus curves showed a VA of 0.1 logMAR or better between -2.5 and + 1.0D with no differences between groups (p > 0.05 at all distances). Overall CSF values remained stable under the induced residual refractions for both groups. The halo effect remained stable for the PanOptix group but increased with myopization in the RayOne group (p = 0.02). The questionnaire showed high rates of patient's satisfaction with no differences between groups. CONCLUSION: Both lenses showed overall good visual outcomes and offered high rates of patient's satisfaction. Moreover, in normal patients with trifocal IOLs, the combination of residual refractive errors and certain amounts of SA may increase some visual disturbances.

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