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Aims, Patients & Methods: Dietary factors may regulate the epigenome. We aimed to explore whether a diet intervention, including excess sugar, affects the methylome in human sperm, and to describe the sperm methylome. We used Whole Genome Bisulfite Sequencing (WGBS) to analyze DNA methylation in sperm taken at three time points from 15 males during a diet intervention; i) at baseline, ii) after one week on a standardized diet, and iii) after an additional week on a high-sugar diet providing 150% of their estimated total energy expenditure., Results: We identified seven nominal diet-associated differentially methylated regions in sperm ( p  < 0.05). The diet was nominally associated with methylation of 143 sites linked to fertility (e.g. AHRR , GNAS , and HDAC4 ), 313 sites in imprinted genes (e.g. GLIS3 , PEG10 , PEG3 , and SNURF ), and 42 sites in top 1%-expressed genes (e.g. CHD2 ) ( p  < 0.05). In sperm, 3'UTRs and introns had the highest levels of methylation, while 5'UTRs and CpG islands had the lowest levels. Non-expressed genes in human sperm were hypomethylated in exons compared with transcribed genes., Conclusions: In human sperm, DNA methylation levels were linked to gene expression, and excess sugar had modest effects on methylation on imprinted and highly expressed genes, and genes affecting fertility.

Aims: Increasing concentrations of dietary sugar results in a linear accumulation of triglycerides in male Drosophila, while inducing a U-shaped obesity response in their offspring. Here, using a combination of proteomics and small RNA (sRNA) sequencing, we aimed at understanding the molecular underpinning in sperm for such plasticity. Results: Proteomic analysis of seminal vesicles revealed that increasing concentrations of dietary sugar resulted in a bell-shaped induction of proteins involved in metabolic/redox regulation. Using stains and in vivo redox reporter flies, this pattern could be explained by changes in sperm production of reactive oxygen species (ROS), more exactly mitochondria-derived H 2 O 2 . By quenching ROS with the antioxidant N-acetyl cysteine and performing sRNA-seq on sperm, we found that sperm miRNA is increased in response to ROS. Moreover, we found sperm mitosRNA to be increased in high-sugar diet conditions (independent of ROS). Reanalyzing our previously published data revealed a similar global upregulation of human sperm mitosRNA in response to a high-sugar diet, suggesting evolutionary conserved mechanisms. Innovation: This work highlights a fast response to dietary sugar in mitochondria-produced H 2 O 2 in Drosophila sperm and identifies redox-sensitive miRNA downstream of this event. Conclusions: Our data support a model where changes in the sperm mitochondria in response to dietary sugar are the primary event, and changes in redox homoeostasis are secondary to mitochondrial ROS production. These data provide multiple candidates for paternal intergenerational metabolic responses as well as potential biomarkers for human male fertility. Antioxid. Redox Signal . 38, 1167-1183.

Early-life stress can result in life-long effects that impact adult health and disease risk, but little is known about how such programming is established and maintained. Here, we show that such epigenetic memories can be initiated in the Drosophila embryo before the major wave of zygotic transcription, and higher-order chromatin structures are established. An early short heat shock results in elevated levels of maternal miRNA and reduced levels of a subgroup of zygotic genes in stage 5 embryos. Using a Dicer-1 mutant, we show that the stress-induced decrease in one of these genes, the insulator-binding factor Elba1, is dependent on functional miRNA biogenesis. Reduction in Elba1 correlates with the upregulation of early developmental genes and promotes a sustained weakening of heterochromatin in the adult fly as indicated by an increased expression of the PEV w m4h reporter. We propose that maternal miRNAs, retained in response to an early embryonic heat shock, shape the subsequent de novo heterochromatin establishment that occurs during early development via direct or indirect regulation of some of the earliest expressed genes, including Elba1., (© 2023 The Authors. Published under the terms of the CC BY 4.0 license.)

Motivation: Feature-based counting is commonly used in RNA-sequencing (RNA-seq) analyses. Here, sequences must align to target features (like genes or non-coding RNAs) and related sequences with different compositions are counted into the same feature. Consequently, sequence integrity is lost, making results less traceable against raw data.Small RNA (sRNA) often maps to multiple features and shows an incredible diversity in form and function. Therefore, applying feature-based strategies may increase the risk of misinterpretation. We present a strategy for sRNA-seq analysis that preserves the integrity of the raw sequence making the data lineage fully traceable. We have consolidated this strategy into Seqpac: An R package that makes a complete sRNA analysis available on multiple platforms. Using published biological data, we show that Seqpac reveals hidden bias and adds new insights to studies that were previously analyzed using feature-based counting.We have identified limitations in the concurrent analysis of RNA-seq data. We call it the traceability dilemma in alignment-based sequencing strategies. By building a flexible framework that preserves the integrity of the read sequence throughout the analysis, we demonstrate better interpretability in sRNA-seq experiments, which are particularly vulnerable to this problem. Applying similar strategies to other transcriptomic workflows may aid in resolving the replication crisis experienced by many fields that depend on transcriptome analyses., Availability and Implementation: Seqpac is available on Bioconductor (https://bioconductor.org/packages/seqpac) and GitHub (https://github.com/danis102/seqpac)., (© The Author(s) 2023. Published by Oxford University Press.)

Small RNA (sRNA) sequencing has been critical for our understanding of many cellular processes, including gene regulation. Nonetheless, the varying biochemical properties of sRNA, such as 5´ nucleotide modifications, make many sRNA subspecies incompatible with common protocols for sRNA sequencing. Here we describe 5XP-seq that outlines a novel strategy that captures a more complete picture of sRNA. By tagging 5´P sRNA during library preparation, 5XP-seq combines an open approach that includes all types of 5'-terminal modifications (5´X), with a selective approach for 5-phosphorylated sRNA (5´P). We show that 5XP-seq not only enriches phosphorylated miRNA and piRNA but successfully discriminates these sRNA from all other sRNA species. We further demonstrate the importance of this strategy by successful inter-species validation of sRNAs that would have otherwise failed, including human to insect translation of several tRNA (tRFs) and rRNA (rRFs) fragments. By combining 5´ insensitive library strategies with 5´ sensitive tagging, we have successfully tackled an intrinsic bias in modern sRNA sequencing that will help us reveal the true complexity and the evolutionary significance of the sRNA world.

The global rise in obesity and steady decline in sperm quality are two alarming trends that have emerged during recent decades. In parallel, evidence from model organisms shows that paternal diet can affect offspring metabolic health in a process involving sperm tRNA-derived small RNA (tsRNA). Here, we report that human sperm are acutely sensitive to nutrient flux, both in terms of sperm motility and changes in sperm tsRNA. Over the course of a 2-week diet intervention, in which we first introduced a healthy diet followed by a diet rich in sugar, sperm motility increased and stabilized at high levels. Small RNA-seq on repeatedly sampled sperm from the same individuals revealed that tsRNAs were up-regulated by eating a high-sugar diet for just 1 week. Unsupervised clustering identified two independent pathways for the biogenesis of these tsRNAs: one involving a novel class of fragments with specific cleavage in the T-loop of mature nuclear tRNAs and the other exclusively involving mitochondrial tsRNAs. Mitochondrial involvement was further supported by a similar up-regulation of mitochondrial rRNA-derived small RNA (rsRNA). Notably, the changes in sugar-sensitive tsRNA were positively associated with simultaneous changes in sperm motility and negatively associated with obesity in an independent clinical cohort. This rapid response to a dietary intervention on tsRNA in human sperm is attuned with the paternal intergenerational metabolic responses found in model organisms. More importantly, our findings suggest shared diet-sensitive mechanisms between sperm motility and the biogenesis of tsRNA, which provide novel insights about the interplay between nutrition and male reproductive health., Competing Interests: The authors have declared that no competing interests exist.

The proinflammatory cytokine interleukin-1β (IL-1β) plays a major role in the signal transduction of immune stimuli from the periphery to the central nervous system, and has been shown to be an important mediator of the immune-induced stress hormone release. The signaling pathway by which IL-1β exerts this function involves the blood-brain-barrier and induced central prostaglandin synthesis, but the identity of the blood-brain-barrier cells responsible for this signal transduction has been unclear, with both endothelial cells and perivascular macrophages suggested as critical components. Here, using an irradiation and transplantation strategy, we generated mice expressing IL-1 type 1 receptors (IL-1R1) either in hematopoietic or non-hematopoietic cells and subjected these mice to peripheral immune challenge with IL-1β. Following both intraperitoneal and intravenous administration of IL-1β, mice lacking IL-1R1 in hematopoietic cells showed induced expression of the activity marker c-Fos in the paraventricular hypothalamic nucleus, and increased plasma levels of ACTH and corticosterone. In contrast, these responses were not observed in mice with IL-1R1 expression only in hematopoietic cells. Immunoreactivity for IL-1R1 was detected in brain vascular cells that displayed induced expression of the prostaglandin synthesizing enzyme cyclooxygenase-2 and that were immunoreactive for the endothelial cell marker CD31, but was not seen in cells positive for the brain macrophage marker CD206. These results imply that activation of the HPA-axis by IL-1β is dependent on IL-1R1s on non-hematopoietic cells, such as brain endothelial cells, and that IL-1R1 on perivascular macrophages are not involved., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Purpose:   To compare spectacles plus alternate-day patching for 8 hr or more with spectacles plus patching for 8 hr or more 6 days weekly to treat strabismic amblyopia 1 year after a 1-year randomized trial., Methods: Forty children (mean age, 4.3 years) participated. Refractive correction was provided. The children were assigned to alternate-day patching for 8 hr or more or patching for 8 hr or more daily 6 days weekly. VA, binocular function, and refractive errors were measured after 2 years. The main outcome measure was the median VA change in the amblyopic eye after 2 years., Results: The median VA change in the amblyopic eye at the 2-year visit was significantly (p = 0.0453) greater with alternate-day patching (0.8 log unit) versus patching daily 6 days weekly (0.6 log unit). The final median VA in the amblyopic eyes was 0.0 logMAR in the alternate-day patching group and 0.1 logMAR in the daily patching group. Binocular function improved with both treatments. The median spherical equivalent (SE) refractive error increased in the fellow eyes (alternate-day patching, p < 0.0001; patching daily 6 days weekly, p = 0.0033); no change was found in the amblyopic eyes in either group., Conclusions: The magnitude of the VA change 2 years after treatment with spectacles plus alternate-day patching for 8 hr or more was significantly greater than with spectacles plus daily patching for 8 hr or more 6 days weekly for strabismic amblyopia. However, the final median VA did not differ significantly between the two treatments., (© 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.)

Interleukin-6 (IL-6) is critical for the lipopolysaccharide (LPS)-induced febrile response. However, the exact source(s) of IL-6 involved in regulating the LPS-elicited fever is still to be identified. One known source of IL-6 is hematopoietic cells, such as monocytes. To clarify the contribution of hematopoietically derived IL-6 to fever, we created chimeric mice expressing IL-6 selectively either in cells of hematopoietic or, conversely, in cells of non-hematopoietic origin. This was performed by extinguishing hematopoietic cells in wild-type (WT) or IL-6 knockout (IL-6 KO) mice by whole-body irradiation and transplanting them with new stem cells. Mice on a WT background but lacking IL-6 in hematopoietic cells displayed normal fever to LPS and were found to have similar levels of IL-6 protein in the cerebrospinal fluid (CSF) and in plasma and of IL-6 mRNA in the brain as WT mice. In contrast, mice on an IL-6 KO background, but with intact IL-6 production in cells of hematopoietic origin, only showed a minor elevation of the body temperature after peripheral LPS injection. While they displayed significantly elevated levels of IL-6 both in plasma and CSF compared with control mice, the increase was modest compared with that seen in LPS injected mice on a WT background, the latter being approximately 20 times larger in magnitude. These results suggest that IL-6 of non-hematopoietic origin is the main source of IL-6 in LPS-induced fever, and that IL-6 produced by hematopoietic cells only plays a minor role., (Copyright © 2013 Elsevier Inc. All rights reserved.)

We investigated to what extent inflammation-induced prostaglandin E2 (PGE2 ) regulates gene expression in the central nervous system. Wild-type mice and mice with deletion of the gene encoding microsomal prostaglandin E synthase-1 (mPGES-1), which cannot produce inflammation-induced PGE2 , were subjected to peripheral injection of bacterial wall lipopolysaccharide (LPS) and killed after 5 h. The median and medial preoptic nuclei, which are rich in prostaglandin E receptors, were isolated by laser capture microdissection (LCM), and subjected to whole genome microarray analysis. Although the immune stimulus induced robust transcriptional changes in the brain, as seen by a quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) on selected genes, only small PGE2 -dependent gene expression changes were observed in the gene array analysis and, for only two genes, a pronounced differential expression between LPS-treated wild-type and mPGES-1 knockout mice could be verified by qRT-PCR. These were Hspa1a and Hspa1b, encoding heat shock proteins, which showed a two- to three-fold higher expression in wild-type mice than in knockout mice after immune challenge. However, the induced expression of these genes was found to be secondary to increased body temperature because they were induced also by cage exchange stress, which did not elicit PGE2 synthesis, and thus were not induced per se by PGE2 -elicited transcriptional events. Our findings suggest that inflammation-induced PGE2 has little effect on gene expression in the preoptic region, and that centrally elicited disease symptoms, although PGE2 -dependent, occur as a result of regulation of neuronal excitability that is a consequence of intracellular, transcriptional-independent signalling cascades. Our findings also imply that the profound changes in gene expression in the brain that are elicited by peripheral inflammation occur independently of PGE2 via a yet unidentified mechanism., (© 2013 British Society for Neuroendocrinology.)

Purpose: To compare spectacle correction alone to spectacle correction with Bangerter filters as treatments for anisometropic amblyopia in children 1 year after completion of a 1-year randomized trial., Methods: In a randomized clinical trial, 80 children (mean age, 4.4 years) with anisometropic amblyopia and a best median visual acuity (VA) in the amblyopic eye of 0.4 logarithm of the minimum angle of resolution (logMAR) were assigned to treatment with either spectacles or spectacles in combination with a Bangerter filter for 1 year. After 1 year, treatment with spectacles continued. If the VA differed by ≥ 2 lines, treatment with Bangerter filters was continued if originally prescribed. The main outcome measure was the median change in VA of the amblyopic eye after 2 years., Results: The median change in VA of the amblyopic eye did not differ significantly between the groups (0.4 log unit for both groups) at the 2-year visit. At that time, the VA in the amblyopic eyes and the fellow eyes was 0.0 median logMAR in both groups. Between years 1 and 2, the median VA improved in the amblyopic eyes; in the spectacles group (p = 0.0181) and in the Bangerter filter group (p = 0.0342). The median anisometropia decreased in both groups (p < 0.0001 for both comparisons)., Conclusion: We found stability in the VA improvement in both groups. The magnitude of the VA change 2 years after treatment with spectacles alone did not differ significantly from that after treatment with spectacles and a Bangerter filter for anisometropic amblyopia., (© 2011 The Authors. Acta Ophthalmologica © 2011 Acta Ophthalmologica Scandinavica Foundation.)

Immune-induced prostaglandin E2 (PGE2) synthesis is critical for fever and other centrally elicited disease symptoms. The production of PGE2 depends on cyclooxygenase-2 and microsomal prostaglandin E synthase-1 (mPGES-1), but the identity of the cells involved has been a matter of controversy. We generated mice expressing mPGES-1 either in cells of hematopoietic or nonhematopoietic origin. Mice lacking mPGES-1 in hematopoietic cells displayed an intact febrile response to lipopolysaccharide, associated with elevated levels of PGE2 in the cerebrospinal fluid. In contrast, mice that expressed mPGES-1 only in hematopoietic cells, although displaying elevated PGE2 levels in plasma but not in the cerebrospinal fluid, showed no febrile response to lipopolysaccharide, thus pointing to the critical role of brain-derived PGE2 for fever. Immunohistochemical stainings showed that induced cyclooxygenase-2 expression in the brain exclusively occurred in endothelial cells, and quantitative PCR analysis on brain cells isolated by flow cytometry demonstrated that mPGES-1 is induced in endothelial cells and not in vascular wall macrophages. Similar analysis on liver cells showed induced expression in macrophages and not in endothelial cells, pointing at the distinct role for brain endothelial cells in PGE2 synthesis. These results identify the brain endothelial cells as the PGE2-producing cells critical for immune-induced fever.

Purpose: To compare spectacles plus patching >or=8 hours daily 6 days a week with spectacles plus patching >or=8 hours on alternate days to treat amblyopia in children 4 to 5 years of age., Design: Prospective, randomized clinical trial., Participants: Forty children (median age, 4.3 years) with untreated amblyopia and a median best-corrected visual acuity (BCVA) in the amblyopic eye of 0.9 (range, 0.3-1.5) logarithm of the minimum angle of resolution., Methods: Refractive correction was provided, and the children were randomized to patching >or=8 hours daily 6 days a week or patching >or=8 hours on alternate days. The BCVA, binocular function, and refractive errors were measured repeatedly during the study., Main Outcome Measure: Median change in BCVA of the amblyopic eye after 1 year., Results: The median change in BCVA of the amblyopic eye did not differ significantly between the 2 groups (0.6 log units for daily occlusion; 0.8 log unit for alternate-day occlusion). The final median BCVA in the amblyopic eyes was 0.1 logarithm of the minimum angle of resolution in both groups. Binocular function improved in both groups with no significant differences between the groups at 1 year. The median spherical equivalent refractive error did not change significantly during the study period in the amblyopic eyes in either group; however, a significant increase was found in the fellow eyes in both groups (daily occlusion, P<0.05; alternate-day occlusion, P<0.001)., Conclusions: The magnitude of change in the BCVA 1 year after spectacles plus prescribed alternate-day patching was not significantly different than that after spectacles plus prescribed daily patching to treat amblyopia in children 4 to 5 years old. The effect of patching was not separate from that of optical correction with a period of refractive adaptation. Thus, the improvement in visual acuity is a combined effect of spectacle wear and occlusion therapy., (Copyright (c) 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare spectacle correction alone with spectacle correction with Bangerter filters to treat anisometropic amblyopia in children., Design: Prospective, randomized clinical trial., Participants: Eighty children (mean age, 4.4 years) with untreated anisometropic amblyopia and a median best-corrected visual acuity (BCVA) in the amblyopic eye of 0.4 logarithm of the minimum angle of resolution (logMAR)., Methods: Optimal refractive correction was provided, and the children were assigned to treatment with either spectacles or spectacles in combination with a Bangerter filter worn on the spectacle lens of the better eye. The BCVA, binocular function, and refractive errors were measured repeatedly over the course of 1 year., Main Outcome Measures: The time course to resolution of the amblyopia (interocular difference, < or =1 line)., Results: The difference in the mean time to the resolution of amblyopia was 3.9+/-3.2 months for the spectacles group versus 2.2+/-1.9 months for the filter group, and the difference reached significance (P<0.05). The BCVA in the amblyopic eye improved significantly (P<0.001 for both comparisons) in both groups. After 1 year, there was no significant difference in the BCVA between the groups. The binocular function improved in both groups; at 1 year there was no significant difference between the groups. The median spherical equivalent refractive error increased significantly during the study in the amblyopic eyes (P<0.05) and the fellow eyes (P<0.001). The median anisometropia decreased significantly from the first visit to the 1-year visit in both groups (P<0.001 for both comparisons)., Conclusions: We found a more rapid visual acuity recovery with the Bangerter filters than with spectacles alone in eyes with anisometropic amblyopia. However, the 1-year visual acuity outcome was not statistically significantly different between the 2 treatments.

Purpose: To evaluate the Perfect Capsule sealed-capsule irrigation device (Milvella Pty., Ltd.) using 3 substances in young rabbit eyes., Setting: St. Erik's Eye Hospital, Stockholm, Sweden., Methods: Thirty 4-week-old rabbits had clear lens extraction in both eyes. In 1 randomly selected eye, the Perfect Capsule was applied and the lens capsule was irrigated for 5 minutes with 1 of 3 substances: balanced salt solution (BSS), distilled deionized water (DDW), or 5-fluorouracil (5-FU) 50 mg/mL. In the other eye, no sealed capsule irrigation was used. Forty days postoperatively, the animals were killed and the eyes fixed in formalin for histologic analysis. After-cataract was evaluated in 3 ways: clinically, from photographs, and histologically. Central posterior capsule thickness was evaluated using a microscope, camera, and computer., Results: The Perfect Capsule sealed-capsule irrigation system could be used in all selected eyes. The vacuum to the anterior capsule was tight, and the system was sealed in all eyes. After-cataract developed in the BSS group and DDW group, but not in the 5-FU group. The 5-FU group had significantly less after-cataract than the other 2 groups (P<.05). There was no difference between the groups in capsule thickness., Conclusions: The Perfect Capsule sealed-capsule irrigation system could be used in small eyes. Distilled deionized water did not prevent after-cataract in rabbit eyes with highly proliferative cells, but 5-FU was effective in preventing after-cataract.

Purpose: To describe the refractive and visual outcomes after surgery for congenital or developmental cataract in the Ukraine., Methods: Cataract surgery was performed in 65 children aged 3-15 years. The cataracts were bilateral in 44 children and unilateral in 21. Examinations, including visual acuity (VA) and objective refraction using retinoscopy, were performed preoperatively and at 1 day, 6 months and 2 years postoperatively. Neither occlusion therapy nor spectacles were prescribed., Results: Almost all children (96%) gained in VA. In all, 40% of the bilateral cases achieved a corrected Snellen VA > or = 0.5 and 44% of the unilateral cases obtained a corrected VA > or = 0.2. The difference between VA (logMAR) preoperatively and 2 years postoperatively was statistically significant (p < 0.05). The bilateral cases showed a postoperative reduction in mean astigmatism from 3.9 D (1 day postoperatively) to 0.6 D (2 years postoperatively) (p < 0.001), while the unilateral cases showed a reduction from 4.2 D (1 day postoperatively) to 0.4 D (2 years postoperatively) (p < 0.001)., Conclusion: Good postoperative VA was achieved in the group with bilateral cataract. Surprisingly, even in the group with unilateral cataract, an increase in VA was obtained, despite the lack of postoperative correction with glasses or occlusion therapy.

Purpose: To evaluate the efficacy and outcome of implantation of a single-piece foldable acrylic intraocular lens (IOL) in children younger than 2 years in the Ukraine., Methods: A total of 31 children from all over the Ukraine with a median age of 11 months (range 2-28 months) underwent cataract surgery with anterior and posterior capsulorhexis, implantation of a single-piece AcrySof SA30AL IOL and anterior dry vitrectomy. Of these, 22 patients attended the last follow-up. Ten patients had follow-up periods of 12 months; 12 had follow-up periods of 18 months. At the postoperative visits, we investigated visual acuity (VA), whether or not the subject had strabismus, lens epithelial cell migration and signs of secondary glaucoma., Results: The single-piece IOL remained clinically centred in all eyes. No secondary glaucoma was detected. Eleven patients needed surgery for after-cataract. All but two patients achieved better VA after surgery. Many patients suffered from deprivation amblyopia as quite a few cataracts were probably congenital; however, the improvement in VA shows that cataract surgery was worth performing despite the late intervention., Conclusion: The foldable single-piece acrylic IOL seems to be well tolerated by children aged 0-2 years. No serious complications were seen and no patient developed secondary glaucoma within the follow-up time. However, lens epithelial cells are very lively in this age group.

Purpose: To evaluate whether cataract surgery in children should be performed with anterior vitrectomy and to examine the properties of the AcrySof SA30AL intraocular lens (IOL) in the pediatric eye., Setting: Filatov Institute, Odessa, Ukraine., Methods: Cataract surgery was performed in 66 children aged 3 to 15 years. They were randomized to surgery with or without anterior vitrectomy. All eyes were implanted with the single-piece AcrySof SA30AL IOL (Alcon). During the study, the patients who needed surgery for after-cataract had a second surgical procedure. Two years after surgery, the surgical method was evaluated using exact logistic regression. Also, the Evaluation of Posterior Capsule Opacification (EPCO) score was compared between the patients who had surgery for after-cataract and the patients who did not need this. The presence of posterior synechias and centration of the IOL were assessed., Results: Children in the younger age group (

Aim: To evaluate the efficacy of two different Swedish screening procedures for early detection of congenital cataracts in comparison with no screening., Methods: Children born between January 1992 and December 1998 in Swedish regions with an established eye-screening routine procedure, diagnosed with congenital cataract, and operated on before 1 y of age, were included in a retrospective study. Age at referral and age at time of the operation were compared between regions using different screening procedures: screening in the maternity wards (Region 1), at the well-baby clinics (Region 2) and one region without any screening (Region 3)., Results: Seventy-two children were included in the study. Concerning early diagnosis and surgery, Region 1 differed significantly from Regions 2 and 3, which were more similar and were combined for further analysis. The difference in detected cases was greatest at 21 d of age (55% vs 18%; p < 0.001), but persisted even at 100 d of age (78% vs 64%; p < 0.02). Region 1 screening resulted in more and earlier cases detected than the other two regions (22 vs 15 per 100,000 births). In 72% of all cases, surgery was performed in response to referrals from either the maternity wards (36%), or the well-baby clinics (36%). However, half of the cases from the well-baby clinics were detected too late, i.e. at > 100 d., Conclusion: Eye screening in the maternity ward is preferable to well-baby clinic screening and to no screening at all, since it leads to early detection. Screening should also be performed routinely at well-baby clinics within the period when successful treatment is possible.

Purpose: To evaluate after-cataract formation, ocular growth, and intraocular lens (IOL) behavior in lensectomized infant rabbit eyes implanted with a downsized heparin-surface-modified poly(methyl methacrylate) (HSM PMMA) IOL with long haptics or a 3-piece AcrySof(R) IOL (Alcon Laboratories, Inc.)., Setting: St. Erik's Eye Hospital, Stockholm, Sweden., Methods: Clear lens extraction was performed in both eyes of 3-week-old rabbits. In Group 1 (n = 9), a downsized HSM PMMA IOL with long haptics was implanted in 1 eye and in Group 2 (n = 9), a 3-piece AcrySof IOL was implanted in 1 eye. The fellow eyes remained aphakic., Results: The amount of after-cataract was significantly less in the eyes with the IOLs than in the aphakic eyes. The eyes with the HSM PMMA IOL had significantly less after-cataract than those with the AcrySof IOL. No significant difference in axial length was noted between the IOL eyes and the aphakic eyes in either group. In the eyes with the 3-piece AcrySof IOL, there was anterior movement of the optic with occlusion of the pupil., Conclusions: Eyes with the HSM PMMA IOL and the AcrySof IOL had less after-cataract than the aphakic eyes. The HSM PMMA IOL, however, inhibited after-cataract production significantly better than the AcrySof IOL. The 3-piece AcrySof IOL was seriously deformed in the infant rabbit eyes and caused occlusion of the pupil. Surgeons should be cautious in implanting this AcrySof IOL in the eyes of newborns or in eyes with severe microphthalmia.

Purpose: To evaluate long-term functional outcome after treatment of dense congenital bilateral cataract., Methods: The records of 22 consecutive children operated on before the age of 12 months at St. Erik's Eye Hospital over a 5-year period (1991-96) were reviewed retrospectively. Linear Snellen visual acuity (VA) at last check, presence of stereoacuity, nystagmus, strabismus and other complications are accounted for. Subject age at last check ranged from 4 to 9 years., Results: Visual acuity could be estimated in 19 children: the median VA of the better eye was 0.4 (range: counting fingers - 0.8) and of the fellow eye 0.15 (range: amaurosis - 0.8). In nine otherwise healthy children who were operated on early (by 1 month of age), VA varied from 0.4 to 0.8 in the better eye. Four of these children achieved stereopsis. Pupillary block glaucoma developed in five eyes (in three children). Chronic glaucoma developed in eight eyes (in five children). Glaucoma occurred predominantly in children who underwent cataract extraction during the first week of life. Two of the latter had marked microphthalmos., Conclusion: Good postoperative VA was achieved in most healthy children with dense bilateral congenital cataract when surgery was performed early (before 6-8 weeks of age). Chronic glaucoma developed predominantly when cataract extraction was performed during the first week of life.

Purpose: To evaluate long-term functional outcome after treatment of congenital unilateral cataract., Methods: The records of 30 consecutive children operated on before the age of 12 months at St. Erik's Eye Hospital over a 5-year period (1991-96) were reviewed retrospectively. The patients were followed until 4-9.5 years of age. Linear Snellen visual acuity (VA), occlusion therapy compliance, and the presence of nystagmus, strabismus and other complications are reported., Results: Six children achieved VA of 0.1 or better. They were all operated on before 3 months of age. Of the 12 infants operated on before 6 weeks of age, four have VA between 0.3 and 0.4 and eight have VA of finger counting or less. Four developed severe secondary glaucoma within 6 months of cataract extraction. Two of these had persistent fetal vasculature. Three eyes developing glaucoma became amaurotic. Occlusion therapy was abandoned before the age of 2.5 years in 21 children., Conclusion: Good levels of VA were achieved only in children who underwent cataract surgery before 3 months of age and who adhered to the occlusion therapy schedule. Severe secondary glaucoma developed in four out of 12 children operated on within 6 weeks. Full compliance with the occlusion therapy programme was uncommon.

Purpose: To evaluate the effects of an intraocular lens (IOL) designed for small eyes after clear lens extraction in an animal model., Setting: St. Erik's Eye Hospital, Karolinska Institute, Stockholm, Sweden., Methods: Clear lens extraction was performed in both eyes in 19 3-week-old rabbits. In 1 randomly selected eye of each rabbit, a small IOL with long haptics was implanted. Axial length, corneal thickness, corneal diameter, and intraocular pressure were measured preoperatively and every month for 6 months postoperatively. Six months after surgery, the wet mass of the after-cataract was determined., Results: The IOL remained well centered in all eyes. Four animals developed severe glaucoma in 5 eyes (3 aphakic and 2 pseudophakic) soon after surgery and were excluded. In the 15 animals completing the study, signs of glaucoma evolved in 7 animals (5 aphakic and 4 pseudophakic eyes). In aphakic eyes, significant amounts of after-cataract (median 250 mg) developed in all 15 surviving animals. In pseudophakic eyes, small amounts of after-cataract (median 30 mg) were present. During the first 2 months after surgery, ocular growth was less in pseudophakic eyes than in aphakic eyes., Conclusions: Results indicate that implantation of a down-sized IOL with long haptics in small eyes is safe. Considerable less after-cataract was found in eyes with the IOL than in aphakic control eyes.

Purpose: To study the association between after-cataract and secondary glaucoma after lensectomy and 5-fluorouracil treatment in an experimental infant rabbit model., Setting: St Erik Eye Hospital, Karolinska Institute, Stockholm, Sweden., Methods: Lensectomy was performed in both eyes of 16 3-week-old rabbits. One randomly selected eye in each rabbit was injected with 2.5 mg of 5-fluorouracil (5-FU) at surgery and 5.0 mg the day after surgery to reduce the formation of after-cataract. Axial length, corneal thickness, corneal diameter, and intraocular pressure were measured preoperatively and 4 times during the 6 months following surgery. Six months after surgery, the wet weight of the after-cataract was determined., Results: In 16 aphakic eyes treated with 5-FU, no or a minimal amount (<0.001 g) of after-cataract developed. None of the eyes showed signs of secondary glaucoma. Of 16 aphakic eyes not treated with 5-FU, 10 developed considerable amounts of after-cataract (>0.10 g); 8 of these developed glaucoma. The other 6 eyes had no or minimal after-cataract and did not develop secondary glaucoma. The relationship between after-cataract and secondary glaucoma was statistically significant., Conclusion: A significant relationship between the amount of after-cataract and the development of secondary glaucoma was found in aphakic infant rabbit eyes.

Background/aims: Prematurely born infants are known to have an increased rate of ophthalmological morbidity. The aim of the present study was to investigate visual acuity and ocular alignment in a population of preterm infants in a geographical area, in infants with and without retinopathy of prematurity (ROP)., Methods: A prospective population based study of ophthalmological status of preterm infants with a birth weight of 1500 g or less was performed during 3.5 years, with examinations at 6, 18, 30, and 42 months of corrected age. Visual acuity was tested using linear optotypes. Multiple regression analyses were used to analyse independent risk factors for poor vision and strabismus., Results: Poor vision (< 0.3) was detected in 2.5% (6/237) of the children. Of these, only two (0.8%) had a severe visual impairment (< 0.1). Strabismus occurred in 13.5% (31/229). Children with cryotreated ROP and neurological complications ran the highest risk of poor vision and strabismus, according to multiple regression analysis. Among children without a history of ROP or neurological complications, 34% had a visual acuity < 0.7 and 5.9% had strabismus, compared with 61% and 22%, respectively, among the children with ROP or neurological complications., Conclusions: The overall incidence of subnormal vision and strabismus in children born prematurely was higher than in a full term population of the same age. On the basis of this study, follow up of all preterm infants screened for ROP is recommended and general guidelines are suggested.

Background: Numerous studies have reported an increased risk of refractive errors in prematurely born infants, but only few have been long-term and strictly population based., Methods: A 3.5 year ophthalmological long term follow up of 248 preterm infants was performed. The infants had been included in a previous epidemiological study of retinopathy of prematurity (ROP) (birth weight < or = 1500 grams). The incidence of refractive errors and development of refraction were studied, based on retinoscopies at 6 and 30 months of corrected age., Results: The overall incidence of myopia was 8% at 6 months, of which 35% was transient, and 10% at 30 months. Of the cryotreated infants, 30-40% were myopic at both retinoscopies. The incidence of astigmatism was 52% at 6 months and 26% at 30 months. Astigmatism was associated with ROP, but not with cryotreated ROP itself. Astigmatism "against the rule" was commoner than astigmatism "with the rule". Anisometropia occurred in 6.5% of the infants at 6 months and in 8.4% at 30 months. The incidence of anisometropia was higher in eyes with ROP, particularly in cryotreated eyes, which tended to have high and persistent anisometropia., Conclusion: The risk of refractive errors is higher in preterm infants than in infants born at term, and also prematurely born infants without ROP do run an increased risk of having myopia and anisometropia. We recommend follow up examinations with retinoscopy for all infants included in screening programmes for ROP.

Purpose: To examine ocular growth in newborn rabbits with a thick or a thin silicone intraocular lens implanted., Methods: Bilateral lensectomy was performed in twelve 23-day-old rabbits. All eyes were implanted with a silicone intraocular lens (IOL) with polypropylene haptics (Allergan Medical Optics SI 26 NB). In each rabbit, one eye was selected at random and a +12 diopter IOL with a centre thickness of 1.10 mm was implanted in the capsular bag. In the other eye a +24 diopter IOL with a centre thickness of 1.83 mm was implanted. Axial length, corneal diameter, corneal thickness and intraocular pressure were measured in all eyes preoperatively, and then 1, 2 and 3 months after surgery. The wet mass of the after-cataract was measured 3 months after surgery., Results: Both the axial length and the corneal diameter were significantly increased in eyes implanted with the thicker silicone IOL. No significant difference in corneal thickness or intraocular pressure was found between the eyes. No correlation was found between the IOL-thickness and the wet mass of the after-cataract., Conclusion: The results suggest that in the young rabbit eye the thickness of an implanted IOL influences eye growth.

Purpose: To examine after-cataract and eye growth in lensectomized newborn rabbits implanted with capsule tension rings of different sizes., Setting: S:t Eriks Eye Hospital, Karolinska Institute, Stockholm, Sweden., Methods: Two groups of 24-day-old rabbits were used. In Group 1 (n = 9), lensectomy was performed in both eyes. In one randomly selected eye, an open poly(methyl methacrylate) (PMMA) capsule tension ring with a 7.0 mm diameter and 0.13 mm thickness was implanted in the capsular bag. The other eye was left aphakic. In Group 2 (n = 10), an open PMMA capsule tension ring with a 10.0 mm diameter and 0.13 mm thickness was implanted in one randomly selected eye, and the other eye was left aphakic. Axial length, corneal diameter, corneal thickness, and intraocular pressure (IOP) were measured in all eyes preoperatively and 1, 2, and 3 months after surgery. The wet mass of the after-cataract was measured at 3 months. Three Group 1 eyes and four Group 2 eyes developed secondary glaucoma and were excluded from the study., Results: Axial growth did not differ significantly between the eyes implanted with the 7.0 mm ring and the aphakic eyes (mean difference 0.01 mm; F3;15 = 0.02; P > .25). Corneal diameter also did not differ (two-way analysis of variance [ANOVA]). Axial length growth was less in the eyes implanted with the 10.0 mm ring than in the aphakic eyes (mean difference 1.05 mm; F3;15 = 2.06; P < .25). The average decrease in corneal diameter growth was 1.0 mm in the implanted eyes. Growth in the eyes with the 10.0 mm ring was significantly less than in the eyes with the 7.0 mm ring (P = .05, Wilcoxon rank-sum test). Corneal thickness and IOP did not differ significantly between eyes (F3;15 = 0.6; P > .25; two-way ANOVA). Amount of after-cataract did not differ significantly between the aphakic eyes and the eyes implanted with the 7.0 mm ring. It was significantly less in the eyes with the 10.0 mm ring than in those with the 7.0 mm ring (Wilcoxon signed-rank test) and in the aphakic eyes (P < .025, Wilcoxon rank-sum test)., Conclusion: In the young rabbit eye, a 10.0 mm capsule ring reduced the eye growth compared with both the aphakic eye and the eye implanted with a 7.0 mm ring. The 10.0 mm ring also inhibited the production of after-cataract compared with the production in the aphakic eye and the eye implanted with the 7.0 mm ring.

Purpose: To examine eye growth in lensectomized infant rabbits implanted with a poly(methyl methacrylate) (PMMA) or a silicone intraocular lens (IOL)., Setting: S:t Eriks Eye Hospital, Karolinska Institute, Stockholm, Sweden., Methods: Two groups of 3-week-old rabbits were used. In Group 1 (n = 13), lensectomy was performed in both eyes. In one randomly selected eye, a +30 diopter (D) heparin-surface-modified (HSM) PMMA IOL was implanted in the capsular bag; the other eye was left aphakic. In Group 2 (n = 10), a +21 D HSM PMMA IOL was implanted in one randomly selected eye and a +21 D silicone IOL was implanted in the other. Axial length, corneal diameter, corneal thickness, and intraocular pressure (IOP) were measured in all eye preoperatively and 1, 2, and 3 months after surgery. The wet mass of the after-cataract was measured 3 months after surgery. The ciliary body with the ciliary processes and the peripheral retina were examined histologically after formalin fixation. The two IOL types were compressed to 7.0 MM, corresponding to the diameter of the 3-week-old rabbit lens., Results: In Group 1, the axial length was significantly decreased in the eye with an HSM PMMA IOL compared with the fellow aphakic eye (P < .01, two-way analysis of variance [ANOVA]). No significant difference in corneal diameter, corneal thickness, or IOP was found between the eyes. The wet mass of the dissected after-cataract was significantly less in the eye implanted with an IOL. Two animals had an elevated IOP with secondary glaucoma in their aphakic eye and were excluded from the study. In Group 2, axial length in eyes with the HSM PMMA IOL was less than in the eyes with the silicone IOL (P < .25, two-way ANOVA). No difference in corneal diameter, corneal thickness, or IOP was found. The amount of after-cataract was not altered. Histologically, the eyes with the HSM PMMA IOL showed retinal degeneration, neovascularization of the ciliary body accompanied by a large number of inflammatory cells, and tumid ciliary processes. The eyes with the silicone IOL showed only minor changes. The aphakic eyes presented even less histological change. The compression test demonstrated that three time the compression force was needed to squeeze the HSM PMMA lens than the silicone IOL., Conclusion: The results suggest that in the young rabbit eye, implanting a regular size HSM PMMA IOL destroys intraocular tissues and reduces eye growth significantly. Replacing the PMMA IOL with a silicone IOL improves the ocular growth.

Ocular axial length and thickness were measured in 12 children (age 4 to 418 days, median 103 days) with unilateral congenital cataract who were referred to St. Erik's Eye Hospital during 1991-1994. The measurements were performed in both eyes with A-scan ultrasonography before cataract extraction. In 4 children measurement of the axial length was repeated 1 to 4 months after the unilateral cataract extraction. All eyes with congenital cataract were shorter than the normal fellow eye. The individual axial length differences showed a mean value +/- SEM of 1.03 +/- 0.16 mm. This difference was statistically significant (P < 0.01). In the 4 children where measurement of the axial length was repeated, the difference between the eyes after unilateral cataract extraction had become greater than before. In addition, the thickness of the cataractous lens was 0.63 +/- 0.17 mm (mean +/- SEM) less than the non-operated clear lens. This difference was statistically significant (p < 0.01). In conclusion, in children with unilateral congenital cataract the affected eye has a shorter axial length and a thinner lens.

Purpose: To examine growth in unilaterally lensectomized newborn rabbits., Setting: S:t Erik Eye Hospital, Karolinska Institute, Stockholm, Sweden., Methods: Unilateral lensectomy was performed in 18 randomly selected 23-day-old rabbits. Corneal incision was performed in 2 other rabbits, and the aqueous humor was replaced with balanced salt solution in one eye. Axial length, corneal diameter, corneal thickness, intraocular pressure (IOP), and refraction were measured in all eyes preoperatively and 1, 2, and 3 months postoperatively. The wet mass of the after-cataract was measured 3 months after surgery., Results: The growth of the aphakic eye, as indicated by axial length and corneal diameter, was significantly less than that of the control eye in 14 rabbits. No significant difference in IOP or corneal thickness was found between the lensectomy and control eyes. Four animals had elevated IOP with secondary glaucoma and were excluded from the study. No difference in eye growth was found between the two eyes when no lensectomy was performed. Refraction in the unoperated eye showed a myopic shift. After lensectomy, the operated eye became hyperopic with a myopic shift 3 months after surgery. No correlation was found between eye growth and the wet mass of the after-cataract., Conclusions: Our results suggest that removal of the rabbit crystalline lens at an early age reduces eye growth.

Purpose: Comparison of the after-cataract formation in newborn rabbits implanted with a heparin-surface-modified (HSM) intraocular lens (IOL), a silicone IOL, or no IOL., Methods: Two groups of 3-week-old rabbits were used. In Group 1 (n = 11), lensectomy was performed in both eyes. One eye was selected at random and an HSM IOL was implanted in the capsular bag; the other eye was left aphakic. In Group 2 (n = 13), lensectomy was performed in both eyes. An HSM IOL was implanted in one eye, a silicone IOL in the other. The wet mass of the dissected after-cataract was determined 3 months after surgery in both groups., Results: In Group 1, the wet mass of the dissected after-cataract was 17.0 +/- 6.5 mg (mean +/- SEM) in eyes implanted with an HSM IOL and 159.7 +/- 17.0 mg in aphakic eyes. This difference was statistically significant (P < .01). In Group 2, the wet mass of the dissected after-cataract was 18.3 +/- 4.3 mg in eyes implanted with an HSM IOL and 25.7 +/- 5.2 mg in eyes implanted with a silicone IOL. No statistically significant difference was found., Conclusions: In young rabbits, implantation of an IOL in the capsular bag following lensectomy reduced cell proliferation.

Cataract surgery was performed in 21 eyes in 14 children (one to 12 years, 5.6 +/- 4.0 [mean +/- SD]). Cataract surgery was standardized and included capsulorhexis of the anterior capsule, irrigation/aspiration of the nucleus and cortex, puncture of the posterior capsule, injection of sodium hyaluronate (Healon GV, 14 mg/ml) between the posterior capsule and the vitreous, and capsulorhexis of the posterior capsule. At the end of the procedure, a heparin-surface-modified (HSM) poly-(methyl methacrylate) intraocular lens (IOL) was implanted in the capsular bag. Follow-up ranged from four to 16 months. No complications such as the appearance of vitreous in the anterior chamber occurred during surgery. A mild postoperative inflammation was seen in all cases. Opacification of the visual axis was seen in one eye ten months after surgery. Posterior synechial formation was seen in one eye. Our results suggest that capsulorhexis of the anterior and posterior capsules with implantation of an HSM IOL in the capsular bag is a safe procedure in children and produces good postoperative results.

Regressed retinopathy of prematurity (ROP) and its sequelae has been analysed in pre-term born children with a birth weight < 1500 g and/or < 33 weeks of gestational age, born in Stockholm during 1976-81. At the age of 5-10 years, we found that 134 of 528 preterm born children (25.4%) had been at departments of ophthalmology in Stockholm for various reasons. These children were re-examined and a good eye fundus information could be obtained in 105. Moderate and severe regressed ROP was found in 48 and 13 children, respectively. In the Stockholm area the frequency of children with severe ROP (earlier called cicatricial ROP) was 2.5% out of the above risk group of 528. Two children were blind from ROP (0.4%). Ten children had a visual acuity < or = 0.3 in the worse eye (1.9%) and 7 of them had ROP changes. Children with a birth weight < 1000 g had the highest frequency of ROP (severe 11.6% and moderate 18.6%) and ocular complications. The results show that preterm born children often present ocular complications, and therefore they need a close follow-up.

Several studies have indicated that operation during the first months of life in children with dense congenital cataract improves the final visual acuity. In the current study seven otherwise healthy children operated on before the age of fifty-six days are compared with seven children operated on after the age of three months. The patients were followed by a team consisting of a paediatric ophthalmologist, a contact lens optician and an orthoptist. They were treated with contact lenses, spectacles with near addition and occlusion therapy when needed. Visual acuity was initially tested with preferential looking technique and later with Snellen optotypes. In the early treated group the visual development was almost normal with a final visual acuity of 20/20, while in the late treated group no patient obtained better visual acuity than 20/100. The findings indicate that dense congenital cataract should be treated before the age of three months.

Linkage analysis was performed in three Swedish families segregating for X-linked retinitis pigmentosa (XLRP), using five polymorphic DNA markers assigned to Xp. Individual recombination events were analyzed and two- and five-point linkage analysis was undertaken. In one family, a XLRP locus was mapped to the same position as OTC corresponding to RP3. In two families, a disease locus linked to OTC was excluded. In one family, recombination events indicate a locus for XLRP outside the interval (DXS84-OTC-DXS255-DXS14), most likely on the centromeric side of DXS14.

Regressed retinopathy of prematurity (ROP) and its sequelae were studied in children born prematurely (less than 1501 g birth weight and/or less than 33 weeks gestational age) in Stockholm county during 1976-81. Through various searches of the records at the different eye departments and other sources in Stockholm county we found that 134 out of a total of 528 premature babies (25.4%) had needed ophthalmic care for different reasons. They were re-examined and reliable information on the fundus could be obtained for 105 of them. The frequency of regressed ROP was 45.5%. Severe forms with vitreoretinal scarring and retinal traction were seen in 9.7% of cases and moderate forms with pigmentary changes and/or vitreoretinal interphase changes in 35.8%. The sequelae of regressed ROP were mainly reduction of visual acuity and myopia. Children with a birth weight below 1000 g and a gestational age less than 30 weeks presented the highest rate of regressed ROP (68.5% and 61.9%) and ocular abnormalities.