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1.
Sci Total Environ ; 857(Pt 1): 159208, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36208746

ABSTRACT

To mitigate radioactive cesium from soil to plant, increasing and maintaining the exchangeable potassium (ExK) level during growth is widely accepted after Tokyo Electric Company's Fukushima Dai-ichi Nuclear Plant accident in Japan. This is because the antagonistic relationship between soil solution K and 134Cs + 137Cs (RCs) concentrations changes the transfer factor (TF: designated as the ratio of radioactivity of plant organ to soil) of RCs. As the relationship between ExK and TF depends on the soil types, crop species, and other environmental factors, the required amount of ExK should be set to a safe side. Eleven years after the accident, as the activity of 134Cs was almost negligible, 137Cs became the main RCs in most of the agricultural fields in Fukushima Prefecture. We propose a new indicator, the concentration ratio of plant 137Cs to soil exchangeable 137Cs (Ex137Cs), instead of TF, which showed a better correlation with ExK even among soils with different properties (or mineralogy).


Subject(s)
Fukushima Nuclear Accident , Radiation Monitoring , Soil Pollutants, Radioactive , Soil Pollutants, Radioactive/analysis , Soil , Cesium Radioisotopes/analysis , Plants , Japan
2.
Sci Total Environ ; 820: 153119, 2022 May 10.
Article in English | MEDLINE | ID: mdl-35041960

ABSTRACT

Non-exchangeable K released from soil minerals can reduce radiocesium transfer to plants, as well as exchangeable K. We investigated the effect of non-exchangeable K on radiocesium transfer to soybean, and the non-exchangeable K extraction method most suitable for estimating the transfer risk. In Fukushima Prefecture, Japan, 106 soils were collected from 89 soybean fields during 2014-2018 to analyze non-exchangeable K contents using three methods: boiling nitric acid extraction, tetraphenyl­boron extraction, and mild tetraphenyl­boron extraction. The non-exchangeable K contents quantified by the former two methods were dependent on the amount of micas, which are K-bearing minerals. The non-exchangeable K content by mild tetraphenyl­boron extraction depended on the amount of K fertilizer application and K-fixing minerals but not on micas, indicating that it reflects fertilizer K fixed by the minerals. The soil-to-plant transfer factor of radiocesium was most correlated with the non-exchangeable K content by the mild extraction (rs = -0.67). This correlation was also stronger than that between exchangeable K and the transfer factor (rs = -0.40). As non-exchangeable K content increased, the exchangeable radiocesium fraction decreased, indicating that radiocesium was fixed together with K. Additionally, multiple regression analysis indicated that non-exchangeable K by the mild extraction significantly decreased the transfer factor even if the exchangeable radiocesium fraction was kept constant. Thus, the fixed K was considered to repress radiocesium transfer to soybean through both radiocesium fixation and K supply. With the criterion of total extracted K, the sum of exchangeable and non-exchangeable K, as 65 mg K2O 100 g-1 by the mild extraction, fields with high and low transfer factors were able to be differentiated more effectively than with a current criterion of exchangeable K as 50 mg K2O 100 g-1. The results revealed that mild tetraphenyl­boron extraction is effective for estimating radiocesium transfer to soybean.


Subject(s)
Fukushima Nuclear Accident , Radiation Monitoring , Soil Pollutants, Radioactive , Boron/analysis , Cesium Radioisotopes/analysis , Japan , Potassium/analysis , Soil Pollutants, Radioactive/analysis , Glycine max
3.
J Environ Radioact ; 237: 106687, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34186241

ABSTRACT

Field and pot experiments were conducted to evaluate the effectiveness of coarse Finnish phlogopite application to reduce radiocesium uptake by paddy rice (Oryza sativa L.). The application of phlogopite was expected to reduce radiocesium uptake by crops through K supply and radiocesium retention. Three fields were set in Fukushima Prefecture, and coarse (mean particle size of 450 µm) phlogopite from Siilinjärvi (Finland) was applied at a rate of 5 t ha-1. Paddy rice was cultivated for 2-4 successive years. In all fields, the average 137Cs transfer factor (TF) of brown rice harvested from plots with added phlogopite was significantly lower than that of brown rice from plots without added phlogopite over the 2-4-year experiments. TF was decreased by up to 80% following phlogopite application, without an adverse effect on yield. Exchangeable K and soil solution K were higher in the soils with added phlogopite, suggesting K released from phlogopite reduced 137Cs uptake by paddy rice. Moreover, in a pot cultivation experiment, even when 55% of the total K was removed from phlogopite prior to application, the TF in pots with phlogopite application was less than half of that in pots without added phlogopite. The results from the field study and the pot cultivation experiment suggested that the application of Finnish phlogopite is effective to reduce the TF of brown rice. Exchangeable K and tetraphenylborate-extractable-K (TPB-K) at rooting stage, and soil solution K at tillering and heading stages showed significant negative correlation with TF. TPB-K was significantly positively correlated with soil solution K at tillering stage and heading stage, whereas exchangeable K at rooting stage did not exhibit significant correlation with soil solution K at heading stage. The results suggest that TPB-K is more reliable than exchangeable K, which could facilitate as a basis of K fertilizer recommendation for radiocesium-contaminated fields.


Subject(s)
Oryza , Radiation Monitoring , Soil Pollutants, Radioactive , Soil Pollutants , Fertilizers/analysis , Finland , Soil , Soil Pollutants/analysis , Soil Pollutants, Radioactive/analysis
4.
Sci Total Environ ; 743: 140458, 2020 Nov 15.
Article in English | MEDLINE | ID: mdl-32758809

ABSTRACT

Phytoavailable K in soil is a key to control the transfer factor of radiocesium from soil to brown rice. The transfer factors were determined for paddy fields cultivated in 2017 and 2018 under different K fertilization regimes in Fukushima Prefecture, Japan. Two phytoavailable forms of K, the exchangeable and nonexchangeable K contents were investigated for the surface soil sampled after the transplanting and fertilization as well as after harvest of rice in the same paddy fields. The exchangeable K content largely decreased from after transplanting and fertilization to after harvest, and the exchangeable K of the soil after harvest was negatively correlated with the transfer factor (rs = -0.70, p < .001). Most soil samples after harvest showed that the transfer factors exponentially increased as the exchangeable K decreased; however, some of the samples indicated considerably low transfer factors (<0.005) despite being exchangeable K deficient, i.e., exchangeable K < 25 mg K2O 100 g-1. Even though this value before usual fertilization has been effectively used as a threshold to determine whether supplemental K fertilization is required to reduce the radiocesium content in brown rice, additional screening was needed to estimate this radiocesium transfer more precisely. Thus, we found that not only the exchangeable K but also nonexchangeable K contents had a negative correlation with the transfer factor (rs = -0.60, p < .001) of the soil samples after harvest but were not correlated with each other (rp = -0.10). Furthermore, the results revealed that soil with nonexchangeable K > 50 mg K2O 100 g-1 indicated a considerably low transfer factor, even if exchangeable K deficient. Thus, via our field-scale experiments, we concluded that the criterion nonexchangeable K > 50 mg K2O 100 g-1 can be used as another threshold for use along with that of exchangeable K to differentiate soil with a low radiocesium transfer rate from exchangeable K deficient soil.


Subject(s)
Fukushima Nuclear Accident , Oryza , Radiation Monitoring , Soil Pollutants, Radioactive/analysis , Cesium Radioisotopes/analysis , Japan , Potassium , Soil
5.
Sci Rep ; 10(1): 3744, 2020 02 28.
Article in English | MEDLINE | ID: mdl-32111908

ABSTRACT

Decreasing the transfer of radioactive cesium (RCs) from soil to crops has been important since the deposition of RCs in agricultural soil owing to the Fukushima nuclear power plant accident of 2011. We investigated the genotypic variation in RCs accumulation in 234 and 198 hexaploid wheat (Triticum spp.) varieties in an affected field in 2012 and 2013, respectively. The effects of soil exchangeable potassium (ExK) content to RCs accumulation in wheat varieties were also evaluated. A test field showed fourfold differences in soil ExK contents based on location, and the wheat varieties grown in areas with lower soil ExK contents tended to have higher grain RCs concentrations. RCs concentrations of shoots, when corrected by the soil ExK content, were positively significantly correlated between years, and RCs concentrations of shoots were significantly correlated with the grain RCs concentration corrected by the soil ExK content. These results indicated that there were genotypic variations in RCs accumulation. The grain to shoot ratio of RCs also showed significant genotypic variation. Wheat varieties with low RCs accumulations were identified. They could contribute to the research and breeding of low RCs accumulating wheat and to agricultural production in the area affected by RCs deposition.


Subject(s)
Cesium Radioisotopes/metabolism , Edible Grain/metabolism , Fukushima Nuclear Accident , Soil Pollutants, Radioactive/metabolism , Triticum/metabolism , Edible Grain/genetics , Japan , Triticum/genetics
6.
J Environ Radioact ; 198: 117-125, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30605858

ABSTRACT

Weathered micaceous minerals (micas) are able to release potassium ion (K+) and fix caesium-137 (137Cs), both of which reduce soil-to-plant transfer of 137Cs. Among micas, trioctahedral micas such as biotite is expected to have a stronger ability to supply nonexchangeable K+ and a higher amount of Cs fixation sites than dioctahedral micas such as illite. Although biotite is predominant in granitic soils (G soils), illite is mainly dominant in sedimentary rock soils (S soils). Therefore, we hypothesized that G soils have a lower 137Cs transfer risk than S soils because of this difference in mineralogy. The objective of the present study was to determine the transfer factor (TF) of 137Cs and stable Cs (SCs) and to elucidate the determinant factors of TFs for G and S soils in Fukushima, Japan. Pot experiments were carried out with rice (Oryza sativa L. cv. Hokuriku 193) in G and S soils to determine the TF of 137Cs (TF-137Cs) and stable Cs (TF-SCs) under K-deficient conditions. TF-137Cs and TF-SCs were highly correlated, and both were significantly lower for G soils than for S soils. Higher TF values were shown for soils with lower amounts of exchangeable and nonexchangeable K or with higher percentages of exchangeable 137Cs (ex137Cs). The percentage of ex137Cs was negatively correlated with the amount of Cs fixation sites, represented by the radiocaesium interception potential. Thus, we concluded that smaller TF values for G soils were caused by a stronger ability to supply nonexchangeable K+ and a higher amount of Cs fixation sites. These findings will contribute to the establishment of soil screening techniques based on 137Cs transfer risk in Fukushima prefecture.


Subject(s)
Cesium Radioisotopes/analysis , Fukushima Nuclear Accident , Soil Pollutants, Radioactive/analysis , Aluminum Silicates , Ferrous Compounds , Japan , Minerals , Oryza , Plants/chemistry , Radiation Monitoring , Silicon Dioxide , Soil/chemistry , Transfer Factor , Weather
7.
J Environ Radioact ; 195: 114-125, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30146184

ABSTRACT

To reduce radiocesium uptake by rice, large amounts of potassium fertilizer have been applied to paddy fields contaminated by radiocesium released from the Fukushima Dai-ichi Nuclear Power Plant owned by the Tokyo Electric Power Company. The Fukushima Prefectural Government recommended maintenance of the soil exchangeable K content up to 200 mg K kg-1 before conventional fertilization in rice production. We constructed an equation to predict the transfer factor from soil to brown rice using the soil exchangeable K content. This equation was then used to calculate the appropriate soil exchangeable K content, which ensures a low risk (5%) of brown rice exceeding the standard limit (100 Bq kg-1 for grains) established in 2012. The equations were constructed using field data obtained by an investigation (measurement of the 137Cs concentrations in soil and brown rice and measurement of the soil exchangeable K content at harvest) that was performed from 2012 to 2015 in 321 paddy fields distributed all over Fukushima Prefecture. We found that the stochastic fluctuation of the transfer factor approximately follows a lognormal distribution under the given environmental conditions. Four factors are considered in predicting the logarithmic quantity of the transfer factor: (1) the linear influence of the logarithm of the exchangeable K content in soil, (2) the non-linear influence of the logarithm of the exchangeable K content in soil, (3) three districts in the Fukushima Prefecture and (4) the year. The linear model of the logarithm of exchangeable K content in soil was adopted by the RD criterion, which indicates the absolute goodness of models for prediction. The predictive ability of the model increased by 29% after including the logarithm of the exchangeable K content in soil (factor 1), while the predictive ability further increased by 10% after including spatial and temporal information (factors 3 and 4). The validity of the exchangeable K content recommended by the Fukushima Prefectural Government was re-examined using the proposed equations, which indicated that the conventional recommendation was appropriate at 2012 but is not fully appropriate under the current situation in which the radiocesium concentration in soil has decreased.


Subject(s)
Cesium Radioisotopes/analysis , Food Contamination, Radioactive/statistics & numerical data , Models, Statistical , Soil Pollutants, Radioactive/analysis , Food Contamination, Radioactive/analysis , Fukushima Nuclear Accident , Japan , Oryza , Radiation Monitoring , Soil
9.
Plant Cell Physiol ; 58(9): 1486-1493, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28922748

ABSTRACT

Incidents at the Fukushima and Chernobyl nuclear power stations have resulted in widespread environmental contamination by radioactive nuclides. Among them, 137cesium has a 30 year half-life, and its persistence in soil raises serious food security issues. It is therefore important to prevent plants, especially crop plants, from absorbing radiocesium. In Arabidopsis thaliana, cesium ions are transported into root cells by several different potassium transporters such as high-affinity K+ transporter 5 (AtHAK5). Therefore, the cesium uptake pathway is thought to be highly redundant, making it difficult to develop plants with low cesium uptake. Here, we isolated rice mutants with low cesium uptake and reveal that the Oryza sativa potassium transporter OsHAK1, which is expressed on the surfaces of roots, is the main route of cesium influx into rice plants, especially in low potassium conditions. During hydroponic cultivation with low to normal potassium concentrations (0-206 µM: the normal potassium level in soil), cesium influx in OsHAK1-knockout lines was no greater than one-eighth that in the wild type. In field experiments, knockout lines of O. sativa HAK1 (OsHAK1) showed dramatically reduced cesium concentrations in grains and shoots, but their potassium uptake was not greatly affected and their grain yields were similar to that of the wild type. Our results demonstrate that, in rice roots, potassium transport systems other than OsHAK1 make little or no contribution to cesium uptake. These results show that low cesium uptake rice lines can be developed for cultivation in radiocesium-contaminated areas.


Subject(s)
Cesium/metabolism , Genes, Plant , Membrane Transport Proteins/genetics , Oryza/genetics , Oryza/metabolism , Plant Proteins/genetics , Plant Roots/metabolism , Potassium/metabolism , Cesium Radioisotopes/metabolism , Environmental Pollution , Genetic Complementation Test , Membrane Transport Proteins/metabolism , Models, Biological , Mutagenesis/genetics , Mutation/genetics , Oryza/drug effects , Phenotype , Plant Proteins/metabolism , Plant Roots/drug effects , Potassium/pharmacology , Solutions
10.
Sci Rep ; 7(1): 2432, 2017 05 25.
Article in English | MEDLINE | ID: mdl-28546542

ABSTRACT

In Japan, radiocesium contamination in foods has become of great concern and it is a primary issue to reduce grain radiocesium concentration in rice (Oryza sativa L.). Here, we report a low-cesium rice mutant 1 (lcs1) with the radiocesium concentration in grain about half that in the wild-type cultivar. Genetic analyses revealed that a mutation in OsSOS2, which encodes a serine/threonine-protein kinase required for the salt overly sensitive (SOS) pathway in plants, is responsible for the decreased cesium (Cs) concentrations in lcs1. Physiological analyses showed that Cs+ uptake by lcs1 roots was significantly decreased under low-potassium (K+) conditions in the presence of sodium (Na+) (low K+/Na+). The transcript levels of several K+ and Na+ transporter genes, such as OsHAK1, OsHAK5, OsAKT1, and OsHKT2;1 were significantly down-regulated in lcs1 grown at low K+/Na+. The decreased Cs+ uptake in lcs1 might be closely related to the lower expression of these genes due to the K+/Na+ imbalance in the lcs1 roots caused by the OsSOS2 mutation. Since the lcs1 plant had no significant negative effects on agronomic traits when grown in radiocesium-contaminated paddy fields, this mutant could be used directly in agriculture for reducing radiocesium in rice grains.


Subject(s)
Cesium/analysis , Mutation , Oryza/chemistry , Oryza/genetics , Protein Serine-Threonine Kinases/genetics , Cation Transport Proteins/genetics , Cation Transport Proteins/metabolism , Cesium Radioisotopes/analysis , DNA Mutational Analysis , Gene Expression Regulation, Plant , Genetic Loci , Phenotype , Protein Serine-Threonine Kinases/metabolism , Sodium/metabolism , Soil Pollutants, Radioactive/analysis
11.
Clin Ophthalmol ; 10: 2149-2155, 2016.
Article in English | MEDLINE | ID: mdl-27826180

ABSTRACT

PURPOSE: To assess the relationship between combined serum lutein and zeaxanthin (L+Z) concentration and macular pigment optical density (MPOD), and to investigate the effect of L+Z+docosahexaenoic acid (DHA) dietary supplementation on the spatial distribution of MPOD. METHODS: Twenty healthy fellow eyes with unilateral wet age-related macular degeneration or chronic central serous chorioretinopathy were included. All participants received a dietary supplement for 6 months that contained 20 mg L, 1 mg Z, and 200 mg DHA. The best-corrected visual acuity and contrast sensitivity (CS) were measured at baseline and at 1, 3, and 6 months. Serum L+Z concentrations were measured at baseline and at 3 months. MPOD was calculated at each time point using fundus autofluorescent images. RESULTS: Serum L+Z concentration was correlated with MPOD at 1°-2° eccentricity at baseline (r=0.63, P=0.003) and 3 months (r=0.53, P=0.015). Serum L+Z concentration increased by a factor of 2.3±1.0 (P<0.0001). At 6 months, MPOD was significantly higher compared to the baseline level at 0°-0.25° (P=0.034) and 0.25°-0.5° (P=0.032) eccentricity. CS improved after 3 or 6 months of L+Z+DHA supplementation (P<0.05). CONCLUSION: Juxtafoveal MPOD was associated with serum L+Z concentration. Foveal MPOD was increased by L+Z+DHA dietary supplementation.

12.
J Environ Radioact ; 153: 188-194, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26773513

ABSTRACT

After the accident at the Fukushima Dai-ichi Nuclear Power Plant owned by the Tokyo Electric Power Company on 11 March 2011, potassium fertilizer was applied to agricultural fields in the southern Tohoku and northern Kanto regions of Japan to reduce the uptake of radiocesium by crops. In this study, we examined the effects of two types of potassium fertilizers, potassium chloride (a readily available potassium fertilizer) and potassium silicate (a slow-release potassium fertilizer), as well as a split application of potassium, on the accumulation of (137)Cs by rice plants in two pot experiments. The (137)Cs concentrations in the brown rice and in the above-ground plants were significantly lower after potassium chloride application than after potassium silicate application. The potassium ion (K(+)) concentrations in soil solutions sampled 9 and 21 d after transplanting were significantly higher for the potassium chloride application than for the potassium silicate application. The K(+) concentrations in soil solutions observed in the application of potassium silicate were similar to those in the treatment when no potassium was applied. This finding indicates that the application of potassium silicate did not sufficiently increase the available K(+) for rice plants in the soil, which led to a greater uptake of (137)Cs after the potassium silicate application than after the application of potassium chloride. The (137)Cs concentration in brown rice was higher in the split application of potassium fertilizer with the second application at the full heading stage than that without split application and the split application with the second application before heading.


Subject(s)
Cesium Radioisotopes/metabolism , Fertilizers/analysis , Oryza/drug effects , Potassium Compounds/pharmacology , Soil Pollutants, Radioactive/metabolism , Japan , Oryza/metabolism , Potassium Chloride/chemistry , Potassium Chloride/pharmacology , Potassium Compounds/chemistry , Silicates/chemistry , Silicates/pharmacology
13.
J Environ Radioact ; 140: 59-64, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25461516

ABSTRACT

The ability to predict radiocesium transfer from soil to agricultural products is necessary for assessing management options in a radiocesium contaminated area. In this study, we evaluated the differences in transfer factors among soil samples and the differences in transfer factors between the first and the second years of contamination in rice. We employed pot experiments using four types of soils that are representative of the agricultural soils present in the Fukushima Prefecture contaminated by (137)Cs released from the Fukushima Dai-ichi Nuclear Power Plant after the March 2011 accident. The experiments were conducted during the 2011 and 2012 growing seasons. The geometric mean of transfer factors for brown rice and inedible rice part was 0.011 and 0.031, respectively, in 2011 and 0.0061 and 0.020, respectively, in 2012. The average decreasing rate of the transfer factor was 40% and 30% in brown rice and inedible rice part, respectively, from 2011 to 2012, presumably owing to the irreversible sorption of (137)Cs to clay minerals.


Subject(s)
Cesium/metabolism , Fukushima Nuclear Accident , Oryza/metabolism , Soil Pollutants, Radioactive/metabolism , Cesium/analysis , Soil Pollutants, Radioactive/analysis
14.
Int J STD AIDS ; 26(7): 516-7, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25033881

ABSTRACT

We report the case of a patient with proliferative diabetic retinopathy, who was later found to have human immunodeficiency virus infection that progressed rapidly. However, we could not determine the clinical course after the onset of human immunodeficiency virus because the patient died shortly after it was detected. In this patient, the activity of proliferative diabetic retinopathy showed regression after treatment for human immunodeficiency virus was initiated.


Subject(s)
Anti-HIV Agents/therapeutic use , Antiretroviral Therapy, Highly Active/methods , Diabetic Retinopathy/complications , HIV Infections/drug therapy , Diabetic Retinopathy/physiopathology , HIV Infections/complications , Humans , Male , Middle Aged , Treatment Outcome
15.
J Environ Radioact ; 138: 122-31, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25222936

ABSTRACT

After the accident at the Fukushima Dai-ichi Nuclear Power Plant owned by Tokyo Electric Power Company on 11 March 2011, potassium was applied to fields in the Tohoku and Kanto areas of Japan to reduce radiocesium uptake by crops. Despite the intense studies relating to the effect of potassium application on availability of radiocesium in the soil, physiological changes of radiocesium uptake by crops in response to K(+) concentration around roots remains elusive. In the present study, we developed physiological models describing the effect of K(+) on the uptake of radiocesium by rice. Two Cs(+):K(+) competition models were evaluated using a wide range of data obtained from pot and field experiments: the model assuming a uniformity in the gene expression of K(+) transporter (Model I) and the model assuming the increase in the gene expression of K(+) transporter in response to K(+) concentration below threshold (Model II). The root-mean-square deviation between the measured and estimated values was larger in Model I than in Model II. Residuals were positively correlated with K(+) in Model I but showed no deflection in Model II. These results indicate that Model II explains the effect of K(+) on the uptake of radiocesium better than Model I. Model II may provide the appropriate countermeasures in inhibiting the transfer of radiocesium from soil to crop. The effect of changes in the variables in Model II on the relationship between available K(+) in soil and (137)Cs uptake by plant was simulated. An increase in available (137)Cs(+) in soil enhanced the response of (137)Cs uptake to K(+). The effects of Michaelis-Menten constant for Cs(+) were the inverse of the (137)Cs(+) effect. The effect of Michaelis-Menten constant for K(+) showed the same tendency as that of (137)Cs(+), but the effect was much less than that of (137)Cs(+). An increase in the threshold of K(+) below which the gene expression of K(+) transporter increases enhanced the response of (137)Cs uptake to K(+) in the high-K(+) range.


Subject(s)
Cesium Radioisotopes/metabolism , Cesium/metabolism , Models, Biological , Oryza/metabolism , Potassium/metabolism , Soil Pollutants, Radioactive/metabolism , Plant Roots/metabolism , Radiation Monitoring , Soil/chemistry
16.
Jpn J Ophthalmol ; 58(5): 443-7, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25096269

ABSTRACT

PURPOSE: To investigate the effects of vitreomacular adhesion (VMA) on intravitreal ranibizumab treatment in Japanese patients with exudative age-related macular degeneration (AMD). METHODS: This was a retrospective comparative study that included 123 eyes from 123 patients with exudative AMD. The presence or absence of VMA was examined by spectral domain optical coherence tomography. The association of VMA with best-corrected visual acuity (BCVA) and central retinal thickness (CRT) at 3, 6, and 12 months after ranibizumab treatment was evaluated. RESULTS: In the group of eyes without VMA [VMA(-)], the mean BCVA was 0.41 logMAR at baseline and significantly improved to 0.28, 0.30, and 0.29 logMAR at 3, 6, and 12 months following the initiation of treatment (P < 0.0001, <0.0001, <0.0001), respectively. In the group of eyes with VMA [VMA(+)], the mean BCVA was 0.42 logMAR at baseline, and there was no improvement at any of the measurement time-points during the follow-up period [0.39, 0.40, and 0.39 logMAR at 3, 6, and 12 months (P = 0.53, 0.75, 0.67), respectively]. The mean baseline CRT in the VMA(-) and VMA(+) groups was 326 and 370 µm, respectively, decreasing to 195 and 293 µm (P < 0.0001 and P = 0.0070), respectively, at 12 months. A better baseline BCVA was associated with poor visual response to intravitreal ranibizumab. CONCLUSIONS: Our study of Japanese patients with AMD managed in real-world clinical practice revealed that both VMA and BCVA at baseline were associated with a poor visual response to intravitreal ranibizumab. These results are in agreement with previously reported findings for other ethnic groups.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Retinal Diseases/complications , Vitreous Body/pathology , Wet Macular Degeneration/drug therapy , Aged , Aged, 80 and over , Female , Humans , Intravitreal Injections , Male , Middle Aged , Ranibizumab , Retinal Diseases/diagnosis , Retrospective Studies , Tissue Adhesions , Tomography, Optical Coherence , Treatment Outcome , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Visual Acuity/physiology , Wet Macular Degeneration/diagnosis
17.
Graefes Arch Clin Exp Ophthalmol ; 251(12): 1-9, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23677486

ABSTRACT

BACKGROUND: The main purpose of this study is to investigate the characteristics of fundus autofluorescence (FAF) and area of soft drusen among the fellow eyes of unilateral typical age-related macular degeneration (typical AMD) and polypoidal choroidal vasculopathy (PCV) in Japanese patients. METHODS: FAF images were obtained from the fellow eyes of unilateral typical AMD (n = 64), unilateral PCV (n = 95), unilateral retinal angiomatous proliferation (RAP) (n = 4) and 56 control subjects, then classified into normal, minimal-change, and abnormal patterns by two graders. Interobserver variability between two graders and intraobserver variability were assessed for FAF classifications, and cases with inconsistent decisions were finally classified by the third grader. Soft drusen were segmented and their total areas were compared between the fellow eyes of typical AMD and PCV. Area(s) with increased autofluorescence were segmented to assess the relationship with soft drusen area(s). RESULTS: Assessment for interobserver variability between two graders and intraobserver variability in one grader showed substantial agreement (κ = 0.70) and almost perfect agreement (κ = 0.85), respectively. In the final decision mediated by third grader, the proportions of eyes with either minimal-change FAF pattern or abnormal FAF pattern in the fellow eyes of both typical AMD (37 cases, 58 %) and PCV (47 cases, 49 %) were significantly higher than that of the control cases (15 cases, 27 %; p < 0.01). The proportion of abnormal FAF pattern in the fellow eyes of typical AMD (20 cases, 31 %) was higher than that of PCV (15 cases, 16 %; p < 0.05). Total soft drusen areas in the fellow eyes of typical AMD (0.369 ± 0.718 mm(2)) were larger than those of PCV (0.173 ± 0.408 mm(2); p < 0.05), and those in the eyes with abnormal FAF pattern were larger than those with minimal-change FAF pattern or normal FAF pattern (p < 0.01). Image analysis revealed a relationship between increased autofluorescence and soft drusen, especially in the cases with large total soft drusen areas. CONCLUSIONS: FAF characteristics were different between the fellow eyes of unilateral typical AMD and PCV in Japan, which might be due to the difference of total soft drusen areas between them.


Subject(s)
Choroidal Neovascularization/diagnosis , Fluorescein Angiography , Polyps/diagnosis , Retinal Drusen/diagnosis , Wet Macular Degeneration/diagnosis , Aged , Asian People/ethnology , Choroidal Neovascularization/ethnology , Coloring Agents , Exudates and Transudates , Female , Fundus Oculi , Humans , Indocyanine Green , Japan/epidemiology , Male , Observer Variation , Polyps/ethnology , Retinal Drusen/ethnology , Wet Macular Degeneration/ethnology
18.
Invest Ophthalmol Vis Sci ; 53(4): 1999-2006, 2012 Apr 18.
Article in English | MEDLINE | ID: mdl-22408007

ABSTRACT

PURPOSE: Several recent studies suggest that some chemokines/chemokine receptors are involved in choroidal neovascularization (CNV). CXCR3 was the focus of the present study because microarray analysis for murine laser-induced CNV model showed the increased expression of CXCR3. The purpose of this study was to evaluate the effect of CXCR3 on CNV. METHODS: Microarray analysis was performed for the mouse eyes with laser-induced CNV. CXCR3 expressions on the CNV were evaluated by immunohistochemistry and real-time RT-PCR. CNV was compared between CXCR3-deficient mice and wild-type mice, between mice treated with anti-CXCR3/anti-IP-10 neutralizing antibody and mice treated with control IgG. Macrophage recruitment into CNV was also investigated. Ocular expressions of vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), C-C chemokine ligand-2 (CCL2), and complement component-3 (C3) were evaluated by real-time PCR. RESULTS: Microarray analysis and real-time RT-PCR revealed the elevation of CXCR3 and IP-10 in laser-treated mouse eyes compared with control eyes. Immunohistochemistry showed CXCR3 expression on the endothelial cells of CNV. Laser-induced CNV of CXCR3-deficient mice was significantly larger, with greater leakage in fluorescein angiography, and with greater macrophage-infiltration compared with wild-type mice (P < 0.01). Intravitreal injection of anti-CXCR3/anti-IP-10 neutralizing antibody exacerbated CNV. The CCL2 expression in the laser-treated eyes of CXCR3-deficient mice was higher than in those of wild-type mice (P < 0.05), whereas VEGF, PEDF, and C3 showed no differences. CONCLUSIONS: These results suggested that CXCR3 expressed on CNV could have an angiostatic effect on it.


Subject(s)
Choroidal Neovascularization/metabolism , Gene Expression Regulation , RNA, Messenger/genetics , Receptors, CXCR3/genetics , Animals , Choroid/metabolism , Choroid/pathology , Choroidal Neovascularization/genetics , Choroidal Neovascularization/pathology , Disease Progression , Female , Fluorescein Angiography , Fundus Oculi , Immunohistochemistry , Male , Mice , Mice, Inbred C57BL , Receptors, CXCR3/biosynthesis , Retinal Pigment Epithelium/metabolism , Retinal Pigment Epithelium/pathology , Reverse Transcriptase Polymerase Chain Reaction
19.
Eye Contact Lens ; 35(6): 345-7, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19812501

ABSTRACT

OBJECTIVES: To report a case of acute high hyperopia occurring after radial keratotomy and evaluate the extent of corneal wavefront aberration with a Hartmann-Shack aberrometer. METHODS: A 45-year-old man had undergone bilateral radial keratotomy with four incisions for myopia 15 years earlier. The patient developed significant hyperopia and irregular corneal astigmatism in the left eye after the operation, reducing his best-corrected visual acuity. RESULTS: The best-corrected visual acuity was 20/20 (with refraction of +0.25-1.50 diopters [D] x 169) in the right eye and 10/20 (with refraction of +9.5D-3.00D x 50) in the left eye. Topography showed marked flattening of the left cornea, and simulated retinal images of Landolt C circles were distorted in the left eye. CONCLUSIONS: This is a rare case in which radial keratotomy induced severe hyperopic shift. Wavefront analysis with a Hartmann-Shack aberrometer revealed severe irregular astigmatism with small clear zones.


Subject(s)
Astigmatism/etiology , Hyperopia/etiology , Keratotomy, Radial/adverse effects , Astigmatism/physiopathology , Cornea/pathology , Corneal Topography/instrumentation , Corneal Wavefront Aberration/diagnosis , Corneal Wavefront Aberration/etiology , Humans , Hyperopia/physiopathology , Male , Middle Aged , Severity of Illness Index , Visual Acuity
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