13 research outputs found

    Imaging techniques for ocular neoplasia

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    Background: Novel ocular imaging modalities have greatly impacted the diagnosis and management of different types of ocular neoplasia. In this narrative review, we summarize the practical features of popular and novel imaging modalities for ocular tumors. Methods: Four databases, including PubMed/MEDLINE, Web of Science, Scopus, and Google Scholar, were searched from January 1, 2000 to August 31, 2022. Articles reporting different imaging modalities for diagnosing or monitoring treatment responses of ocular tumors were extracted using various combinations of the following keywords: ocular neoplasia, positron emission tomography or PET, single-photon emission computed tomography or SPECT, optical coherence tomography or OCT, OCT angiography or OCTA, computed tomography or CT, ultrasonography or US, ultrasound biomicroscopy or UBM, and magnetic resonance imaging or MRI. Results: Various ocular imaging modalities had different accuracies as adjunctive tools for detecting or managing ocular tumors. Anterior ultra-high-resolution optical coherence tomography (OCT) could be used to evaluate images with < 5-µm resolution. OCT angiography provided deeper insight into retinal vascular changes associated with the malignant transformation of choroidal melanoma. OCT in children altered the diagnosis of suspicious retinoblastoma in 3% of the cases and treatment plan in 11% of the cases. While positron-emission tomography (PET)/computed tomography (CT) allowed the detection of metastatic lesions of choroidal melanoma by full-body scanning, single-photon emission CT was more sensitive compared to PET in detecting choroidal melanoma. Ultrasound biomicroscopy, with an accuracy exceeding 92.5%, could detect retinal calcification in lesions measuring 2–3 mm. Magnetic resonance imaging (MRI) had better contrast compared to ultrasound biomicroscopy and higher sensitivity compared to CT in detecting post-laminar optic nerve invasion. However, MRI had a lower spatial resolution compared to OCT. Further development of imaging modalities and their application in drug development would improve the treatment of ocular tumors. Conclusions: Although diagnosing ocular tumors depend on clinical characteristics, innovations in ocular imaging have enabled early diagnosis and timely, appropriate management of ocular neoplasia, which are conducive to favorable visual outcomes and increased life expectancy. Further systematic reviews and meta-analyses of primary studies focusing on a specific imaging modality in ocular neoplasia could precisely determine the diagnostic accuracy of each imaging modality to better guide eye practitioners with efficient diagnostic or therapeutic approaches for these sight- or life-threatening entities. Imaging modalities may play a major role in drug development in the future

    Impacts of climate change on soybean production under different treatments of field experiments considering the uncertainty of general circulation models

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    Earth is faced with dramatic changes in the weather systems, which leads to climate change. Climate change affects water resources and crop production. In this study, five and seven general circulation models (GCMs) were respectively collected via the IPCC Fourth and Fifth Assessment Reports. Emission scenarios including B1, A1B, and A2 for AR4 and RCP2.6 and RCP8.5 for AR5 were applied to predict future climate change. The weighting method of mean observed temperature-precipitation (MOTP) was utilized to compute uncertainty related to different climate models. The scenario files made by ΔT and ΔP were applied to the downscaled model of LARS-WG to generate weighted multi-model ensemble means of temperature and precipitation for the period 2020–2039 centered on 2030s. These ensemble means were incorporated into the calibrated AquaCrop model to predict final yield and biomass. In this study, soybean data were applied for four different varieties under three irrigation treatments in field experiments carried out at Karaj Seed and Plant Improvement Institute in two successive years. However, the results of statistical analysis between the model output and observed data for all varieties and irrigation treatments in the calibration year (2010) and validation year (2011) were the same at the 95% confidence level. It is suggested that AquaCrop is a valid model to predict yield and biomass for the study area in the future. Furthermore, comparing future climatic variables to the historical period during the soybean growing season showed enhancement of these variables by the 2030s. The amplitude change of temperature was larger in AR5, whereas the amplitude change of precipitation and CO2 were larger in AR4. The soybean yield and biomass increased for all treatments in the 2030 s with positive correlation with the climatic variables. The maximum temperature represented the most significant correlation with yield and biomass for almost all treatments. Finally, soybeans might achieve an optimal threshold temperature in the future, leading to yield increases in the 2030s

    Epigenetic Diabetic Vascular Complications

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    Diabetic vascular complications (DVC) influence several vital organ systems including cardiovascular, renal, ocular and nervous systems making it a major public health problem. Although extensive researches were performed in this field, the exact mechanisms responsible for these organ damages in diabetes remain obscure. Several metabolic disturbances have been involved in its complication and change in genes associated with these pathways occurred. Gene expression to produce a biologically active protein can be controlled by transcriptional and translational alteration on the head of genes without change in nucleotide composition. These epigenetic adjustments are steady, but possibly reversible and can be transmitted to future generation. Gene expression can be regulated by three epigenetic mechanisms including DNA methylation, histone modifications and noncoding microRNAs (miRNAs) activity. Epigenetic studies must be directed to better realize the role of epigenetic changes to the etiology of DVC and knowledge of epigenetic would play a pivotal role in the application of individualized medicine. Application and development of high technology sequencing combined with more sensitive and advanced methodologies for epigenome studying help to determine specific epigenetic events that stimulate gene responses in patients with diabetes mellitus

    Epigenetic Diabetic Vascular Complications

    No full text
    Diabetic vascular complications (DVC) influence several vital organ systems including cardiovascular, renal, ocular and nervous systems making it a major public health problem. Although extensive researches were performed in this field, the exact mechanisms responsible for these organ damages in diabetes remain obscure. Several metabolic disturbances have been involved in its complication and change in genes associated with these pathways occurred. Gene expression to produce a biologically active protein can be controlled by transcriptional and translational alteration on the head of genes without change in nucleotide composition. These epigenetic adjustments are steady, but possibly reversible and can be transmitted to future generation. Gene expression can be regulated by three epigenetic mechanisms including DNA methylation, histone modifications and noncoding microRNAs (miRNAs) activity. Epigenetic studies must be directed to better realize the role of epigenetic changes to the etiology of DVC and knowledge of epigenetic would play a pivotal role in the application of individualized medicine. Application and development of high technology sequencing combined with more sensitive and advanced methodologies for epigenome studying help to determine specific epigenetic events that stimulate gene responses in patients with diabetes mellitus

    A Clinical and Genetic Review of Aniridia

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    Aniridia is a congenital pan-ocular, bilateral disorder. The term aniridia is a misleading misnomer, since at least a rudimentary iris is always present. Varied forms range from almost total absence to only mild hypoplasia of the iris. It is inherent in a number of syndromes, including Wilms tumor Aniridia-Genital anomalies-retardation (WAGR). Aniridia has been shown to be associated with mutations in the PAX6 gene, located on chromosome 11p13, telomeric to the Wilms’ tumor predisposition gene (WT1). The pair box gene 6 (PAX6) situated at 11p13 has been confirmed to be the leading gene associated with aniridia. The PAX6 mutation is present in individuals worldwide and has been studied in Indian, Malaysian, Chinese and Mexican families. Several categories of PAX6 mutations include: nonsense mutations, splicing mutations, frameshift mutations (deletion or insertion), in-frame insertion or deletion, missense mutations and run-on mutations. A novel de novo frameshift mutation in PAX6 most possibly occurred in the paternal gamete. Mutation in PAX6 brings about amino acid substitution for instance proline to glutamine. Deletion of 11p13 involves the PAX6 (aniridia) locus and the adjacent WT1 (Wilms tumor) locus. Haploinsufficiency at the PAX6 locus brings on aniridia, a pan-ocular eye condition characterized by iris hypoplasia and various other anterior and posterior eye defects, subtle hypogonadotropic hypogonadism and borderline Growth Hormone (GH) deficiency. Aniridia may also be affiliated with retinal tears and detachments. Electroretinograms (ERGs) done in aniridia illustrate definite retinal dysfunction. Other clinical aspects related to aniridia are ptosis with reduced levator function and anterior polar cataracts. The PAX6 gene mutation was also associated with early-onset diabetes mellitus and aniridia. Aniridia combined with zonular cataract and polydactyly was also described in a patient with Bardet-Biedl syndrome. Aniridia with sensorineural deafness (cochlear) and aplasia of the patella was also reported; an autosomal-dominant inheritance with 100% penetrance. The WAGR syndrome is associated with obesity. Because of all the associations with other diseases as mentioned above, ophthalmologists should pay more attention to aniridia as a sign of a systematic disease. As aniridia is a global disease and has been reported in all five continents and several countries with different ethnic groups, herein we reviewed this important disorder

    A Clinical and Genetic Review of Aniridia

    No full text
    Aniridia is a congenital pan-ocular, bilateral disorder. The term aniridia is a misleading misnomer, since at least a rudimentary iris is always present. Varied forms range from almost total absence to only mild hypoplasia of the iris. It is inherent in a number of syndromes, including Wilms tumor Aniridia-Genital anomalies-retardation (WAGR). Aniridia has been shown to be associated with mutations in the PAX6 gene, located on chromosome 11p13, telomeric to the Wilms’ tumor predisposition gene (WT1). The pair box gene 6 (PAX6) situated at 11p13 has been confirmed to be the leading gene associated with aniridia. The PAX6 mutation is present in individuals worldwide and has been studied in Indian, Malaysian, Chinese and Mexican families. Several categories of PAX6 mutations include: nonsense mutations, splicing mutations, frameshift mutations (deletion or insertion), in-frame insertion or deletion, missense mutations and run-on mutations. A novel de novo frameshift mutation in PAX6 most possibly occurred in the paternal gamete. Mutation in PAX6 brings about amino acid substitution for instance proline to glutamine. Deletion of 11p13 involves the PAX6 (aniridia) locus and the adjacent WT1 (Wilms tumor) locus. Haploinsufficiency at the PAX6 locus brings on aniridia, a pan-ocular eye condition characterized by iris hypoplasia and various other anterior and posterior eye defects, subtle hypogonadotropic hypogonadism and borderline Growth Hormone (GH) deficiency. Aniridia may also be affiliated with retinal tears and detachments. Electroretinograms (ERGs) done in aniridia illustrate definite retinal dysfunction. Other clinical aspects related to aniridia are ptosis with reduced levator function and anterior polar cataracts. The PAX6 gene mutation was also associated with early-onset diabetes mellitus and aniridia. Aniridia combined with zonular cataract and polydactyly was also described in a patient with Bardet-Biedl syndrome. Aniridia with sensorineural deafness (cochlear) and aplasia of the patella was also reported; an autosomal-dominant inheritance with 100% penetrance. The WAGR syndrome is associated with obesity. Because of all the associations with other diseases as mentioned above, ophthalmologists should pay more attention to aniridia as a sign of a systematic disease. As aniridia is a global disease and has been reported in all five continents and several countries with different ethnic groups, herein we reviewed this important disorder

    Hydroxychloroquine Induced Retinopathy: A Case Series

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    Background and Purpose: Occular toxicity is one of the most important complications of Hydroxychloroquine. Not any type of treatment has so far been found and recommended for this disorder. The purpose of this study was to report some characteristics of patients with Hydroxychloroquine Induced Retinopathy.    Materials and Methods: From 107 patients with rheumatoid arthritis (RA) and/or systemic lupus erythematosus (SLE) during 2013-14 in Sari, Iran, who were selected by a simple sampling method and were referred to hospitals for ophthalmologic examinations, 21 patients were found with HCQ induced retinopathy. The Examination for HCQ-induced maculopathy was performed through fundoscopy, perimetry or optical coherence tomography (OCT), and the physicians had their own discretion based on the examination. Although the patients were examined by different ophthalmologists, all of them were evaluated by the same device (Zeiss cirrus HD OCT4000.USA for OCT, Zeiss Humphrey Field analyzer 2i. USA for visual field, and Topcon. TRC.50Dx. Japan for angiography). Based on the collected data, the characteristics of clinical and ophthalmologic changes were reported, and the data were analysed through Independent Sample t Test and χ2.    Results: 21 patients (19 females) with a mean age of 49.86 (±15.6) were evaluated during 4.95 (±4.7) years of therapy. The mean of cumulative dose was calculated to be 313.18±269.8 grams. Based on the findings, hypertension was detected in 5 (23.8%) of the patients. Conclusion: In the present study, it was found that HCQ induced retinal toxicity may occur even in recommended doses or for less than 5 years. Other risk factors such as hypertension in addition to the dose or duration of toxicity could also accelerate retinal toxicity

    The Upregulation of HLA-G1 and miRNA-34a in Lens Epithelial Cells of Diabetic Retinopathy Patients

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    Background: Retinopathy of diabetes is a chronic diabetes mellitus complication affecting retinal vessels, and some ocular complications’ molecular mechanisms remain obscure.Objective: To evaluate the expression of HLA-G1, HLA-G5, miRNA-181a, and miRNA-34a in the lens epithelial cells of patients with retinopathy of diabetes.Methods: In a case-control study, 30 diabetic patients with retinopathy, 30 diabetic patients without retinopathy, and 30 cataract patients without diabetes mellitus as the control group were enrolled after a full description with details about the study methods and objectives. The expression of HLA G1, HLA G5, miRNA-181a, and miRNA-34a in lens epithelial cells was assessed by quantitative RT PCR. Moreover, the levels of HLA-G protein in aqueous humor were evaluated by the ELISA method.Results: HLA-G1 expression was significantly upregulated in the retinopathy group (P=0.003). The aqueous humor of diabetic retinopathy patients contained significantly higher levels of HLA-G protein compared with the non-diabetic patients (P=0.001). miRNA-181a was significantly downregulated in the diabetic retinopathy group compared with the patients without diabetes (P=0.001). In addition, miRNA-34a was upregulated in the retinopathy group (P=0.009).Conclusion: Taken together, the present results showed that HLA-G1 and miRNA-34a can be valuable markers for diabetic retinopathy. Our data offers new perspectives for improving the control of inflammation in the lens epithelial cells by considering HLA-G and miRNA

    The Prevalence of Astigmatism in 7 to 13 Years Old Children: A Cross-sectional Study

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    Background: Refractive errors are among the most common causes of vision loss in patients attending healthcare facilities in the first and second decades of life. Astigmatism stands out as one of the common and treatable causes of vision loss in pediatrics.  Methods: In this cross-sectional study, the samples were chosen by random cluster sampling among children aged between 7 and 13 years from elementary schools in 2014-2015 academic year. For all students, refractive errors were assessed by Autorefractor Keratometer and retinoscopy. Internal astigmatism was defined as the difference between refractory and corneal astigmatism. SPSS software, version 16 was used for data analysis. Results: A total of 1009 children participated in the study. Among them, 468(46.4%) were male, and 541(53.6%) were female. Their mean age was 9.2±1.7 years. About 14.5% of them had refractory astigmatism. Corneal astigmatism was the most common type, with 12.5% of students suffering from it. The prevalence of corneal astigmatism was not significantly different between males and females (P=0.19). Also, there was no significant relationship between increasing age and prevalence of astigmatism in this age group (P=0.06). Conclusions: There was no significant difference in the rate of refractory astigmatism, lenticular and corneal astigmatism, between males and females. Because correcting refractory errors in students has a positive effect on learning ability and physical and mental development, screening and follow-up are recommended in this age group

    Evaluation of the frequency of ABO and Rh-Hr blood-group systems in different acquired cataracts type

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    Abstract Objectives This study evaluated the relationship between acquired cataract’s different types and the ABO and Rh blood classes. Methods Overall, 520 patients, by randomized sampling method, participated in this retrospective cross-sectional study. After reviewing the patient’s medical records and laboratory results, the patient’s demographics, ABO group, Rh, and cataract type were documented. Results A total of 520 patients were included in the research, with a mean age of 67.57 ± 11.85. Most of them were female (n = 286, 55%). Mix (n = 230, 44%) and nuclear sclerotic (NS) (n = 167, 32%) cataracts were the most common types. The posterior subcapsular cataract (PSC) prevalence in females was significantly higher than in males (16.1% vs.7.3% p = 0.002). Also, men had more NS cataracts than females (89, 38% vs. 78, 27.3%) (p = 0.009). Patients with PSC were significantly younger than others (all p-values  0.05). Conclusion Although our findings showed that cataract types are independent of blood group types and Rh, they can be compared with future studies on the association of other Blood-Group Systems in developing acquired cataracts
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