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In the face of an "epidemic" increase in myopia over the last decades and myopia prevalence predicted to reach 2.5 billion people by the end of this decade, there is an urgent need to develop effective and safe therapeutic interventions to slow down this "myopia booming" and prevent myopia-related complications and vision loss. Dopamine (DA) is an important neurotransmitter in the retina and mediates diverse functions including retina development, visual signaling, and refractive development. Inspired by the convergence of epidemiological and animal studies in support of the inverse relationship between outdoor activity and risk of developing myopia and by the close biological relationship between light exposure and dopamine release/signaling, we felt it is timely and important to critically review the role of DA in myopia development. This review will revisit several key points of evidence for and against DA mediating light control of myopia: 1) the causal role of extracellular retinal DA levels, 2) the mechanism and action of dopamine D1 and D2 receptors and 3) the roles of cellular/circuit retinal pathways. We examine the experiments that show causation by altering DA, DA receptors and visual pathways using pharmacological, transgenic, or visual environment approaches. Furthermore, we critically evaluate the safety issues of a DA-based treatment strategy and some approaches to address these issues. The review identifies the key questions and challenges in translating basic knowledge on DA signaling and myopia from animal studies into effective pharmacological treatments for myopia in children. [ABSTRACT FROM AUTHOR]

Herein, we report on the synthesis of film-forming poly(styrene- co-butyl acrylate- co-acrylic acid)/SiO [P(St-BA-AA)/SiO] nanocomposites by in situ formation of SiO nanoparticles from TEOS via sol-gel process in the presence of poly(acrylic acid) (PAA)-functionalized poly(styrene- co-butyl acrylate) [P(St-BA)] particles fabricated by soap-free emulsion polymerization. The formed silica particles could be absorbed by polyacrylate chains on the surface of PAA-functionalized P(St-BA) particles; thus, raspberry-like polymer/silica nanocomposites would be obtained. Transmission electron microscopy, Fourier transform infrared spectroscopy, attenuated total reflectance infrared spectrum, ultraviolet-visible transmittance spectra, and thermogravimetric analysis were used to characterize the resulting composites. The results showed that the hybrid polymer/silica had a raspberry-like structure with silica nanoparticles anchored on the surface of polymer microspheres. The thermal, fire retardant, and mechanical properties and water resistance of the film were improved by incorporating silica nanoparticles, while the optical transmittance was seldom affected due to nanosized silica particles uniformly dispersed in the film. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: The ND4 G11778A mutation is the most common mitochondrial DNA mutation leading to Leber''s hereditary optic neuropathy (LHON). Despite considerable clinical evidences, the modifier role of nuclear background and mitochondrial haplotypes in phenotypic manifestation of LHON remains poorly understood. We investigated the effect of these modifiers on bioenergetics in lymphoblastoid cell lines derived from five affected subjects of one Chinese family carrying the G11778A mutation and five Chinese controls. Significant reductions in the activities of complexes I and III were observed in mutant cell lines from the Chinese family, whereas the mutant cell lines from other families carrying the same mutation exhibited only reduced activity of complex I. The reduced activities of complexes I and III caused remarkably higher reductions of ATP synthesis in mutant cell lines from the Chinese family than those from other families. The deficient respiration increased generation of reactive oxygen species. The defect in complex III activity, likely resulting from the mitochondrial haplotype or nuclear gene alteration, worsens mitochondrial dysfunction caused by the G11778A mutation, thereby causing extremely high penetrance and expressivity of optic neuropathy in this Chinese family. Our data provide the first experimental evidence that altered activity of complex III modulates the phenotypic manifestation of LHON-associated G11778A mutation. Thus, our findings may provide new insights into the pathophysiology of LHON. [Copyright &y& Elsevier]

Purpose: To investigate the molecular pathogenesis of Leber''s hereditary optic neuropathy (LHON) in Chinese families. Design: Six Han Chinese families who seem to have maternally transmitted LHON were studied by clinical, genetic, and molecular evaluations. Participants: One hundred twenty-seven subjects from 6 Chinese families with a wide range of age-at-onset and severity of visual impairment. Methods: All subjects underwent clinical examination, genetic evaluation, and molecular analysis of mitochondrial DNA (mtDNA). Main Outcome Measures: The ophthalmologic examinations included visual acuity, visual field examination, visual evoked potentials, and fundus photography. The mtDNA analysis included the polymerase chain reaction (PCR) amplification of entire mtDNA and subsequent sequence determination. Results: Six families exhibited low penetrance of visual impairment, with an average of 10.8%. In particular, 9 (6 males/3 females) of 86 matrilineal relatives in these families exhibited variable severity and age at onset in visual dysfunction. The average age at onset of visual loss was 20 years. Molecular analysis of mtDNA in these families identified the homoplasmic ND5 T12338C mutation and distinct set of variants belonging to the Asian haplogroup F2. The T12338C mutation is only present in the maternal lineage of those pedigrees and not in 178 Chinese controls. This mutation resulted in the replacement of the first amino acid, a translation-initiating methionine with a threonine, shortening 2 amino acids of ND5 polypeptide. The T12338C mutation is also located in 2 nucleotides adjacent to the 3′ end of the tRNALeu(CUN). Thus, this mutation may alter ND5 mRNA metabolism and the processing of RNA precursors. As a result, this mutation impairs respiratory function, leading to visual impairment. Conclusions: Several lines of evidence suggest that the mitochondrial ND5 T12338C mutation is associated with LHON. The tissue specificity of this mutation is likely due to the involvement of nuclear modifier genes. The identification of nuclear modifiers is important for the elucidation of the pathogenic mechanism of LHON and an open avenue for therapeutic interventions. The T12338C mutation should be added to the list of inherited risk factors for future molecular diagnosis. Our findings are helpful for counseling families with LHON. Financial Disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article. [Copyright &y& Elsevier]

Abstract: We report here the clinical, genetic and molecular characterization of four Han Chinese families with Leber''s hereditary optic neuropathy (LHON). The penetrances of optic neuropathy in these Chinese pedigrees were 38%, 38%, 44% and 56%. This observation is in contrast with the previously identified 14 Chinese families with very low penetrance of LHON. The age-at-onset for visual impairment in matrilineal relatives in these Chinese families varied from 18 to 30years. Furthermore, the ratios between affected male and female matrilineal relatives in these families were 3:0, 3:0, 3:1 and 2:3, respectively. Molecular analysis of mitochondrial genomes identified the known ND4 G11778A mutation and distinct sets of variants belonging to the Asian haplogroups M9a. Of these, the ND1 T3394C mutation caused the substitution of a highly conserved histidine for tyrosine (Y30H) at amino acid position 30. This mutation was associated with LHON in other families with low penetrance of optic neuropathy and other clinical abnormalities. The presence of both G11778A and T3394C mutations appears to contribute to higher penetrance of optic neuropathy in these four Chinese families than other Chinese families carrying only the G11778A mutation. Therefore, the mitochondrial haplogroup M9a specific variant T3394C may modulate the phenotypic manifestation of LHON-associated G11778A mutation in these Chinese pedigrees. [Copyright &y& Elsevier]

Abstract: We report here the clinical, genetic, and molecular evaluations of four Han Chinese families with Leber’s hereditary optic neuropathy. Thirty-one (20 males/11 females) of 83 matrilineal relatives in these families exhibited the variable severity and age-at-onset in visual impairment. The average age-of-onset of vision loss was 22years old. Strikingly, these penetrances of visual impairment in these Chinese families were higher than those in other 11 Chinese pedigrees carrying the only ND4 G11778A mutation. Molecular analysis identified the known G11778A mutation and distinct sets of variants belonging to the Asian haplogroups M10a and M7c2. Of these, the T14502C mutation caused the substitution of a highly conserved isoleucine for valine at position 58 in ND6. This mutation has been associated with LHON in other Chinese families with very low penetrance of LHON. Thus, the deficient activities of complex I, caused by G11778A mutation, would be worsened by the T14502C mutation in these four Chinese families. As a result, mitochondrial dysfunctions would lead to the high penetrance and expressivity of visual loss in these Chinese families carrying both G11778A and T14502C mutations than other 11 Chinese families carrying only G11778A mutation. These data suggested that the T14502C variant may modulate the phenotypic manifestation of the G11778A mutation in these Chinese pedigrees. [Copyright &y& Elsevier]

Abstract: We report here the clinical, genetics and molecular characterization of a five-generation Han Chinese family with Leber’s hereditary optic neuropathy (LHON). Strikingly, this family exhibits very high penetrance and occurrence of optic neuropathy. In particular, 25 (10 males/15 females) of 30 matrilineal relatives exhibited the variable severity, ranging from profound to mild of visual impairment. This penetrance of optic neuropathy in this Chinese family is much higher than those in many families with LHON worldwide. The age-at-onset for visual impairment in matrilineal relatives in this Chinese family varied from 7 to 24years old, with the average of 15years old. Furthermore, the ratio between affected male and female matrilineal relatives is 1:1.5 in the Chinese family. This observation is in contrast with the typical features in LHON pedigrees that there was predominance of affected males in LHON in many families from different ethnic origins. Molecular analysis of mitochondrial genome identified the known ND4 G11778A mutation and 51 variants, belonging to Asian haplogroup C4a1. The absence of other known secondary LHON-associated and functionally significant mtDNA mutations in this Chinese family suggested that mitochondrial variants may not play an important role in the phenotypic manifestation of the G11778A mutation in this Chinese family. Therefore, nuclear modifier gene(s) may be responsible for very high penetrance and occurrence of optic neuropathy in this Chinese pedigree. [Copyright &y& Elsevier]

Abstract: Background: Leber’s hereditary optic neuropathy (LHON) is a maternally inherited disorder. The purpose of this investigation is to understand the role of mitochondrial haplotypes in the development of LHON associated with ND6 T14484C mutation in Chinese families. Methods: One hundred fourteen subjects from ten Han Chinese families with LHON were studied by the clinical and genetic evaluation as well as molecular and biochemical analyses of mitochondrial DNA (mtDNA). Results: Clinical evaluation revealed that ten families exhibited extremely low penetrance of visual impairment, with an average of 10%. In particular, ten (8 males/2 females) of 114 matrilineal relatives in these families exhibited the variable severity and age-at-onset in visual dysfunction. The average age-of-onset of vision loss was 19 years old. Molecular analysis of mitochondrial DNA (mtDNA) identified the homoplasmic T14484C mutation and distinct sets of variants, belonging to the Asian haplogroups B5b, D4, D4g1b, G3a2, R11, R11a and Z3, respectively. However, there was the absence of secondary LHON-associated mtDNA mutations in these ten Chinese families. Conclusion: The low penetrance of vision loss in these Chinese pedigrees strongly indicated that the T14484C mutation was itself insufficient to produce a clinical phenotype. The absence of secondary LHON mtDNA mutations suggests that these mtDNA haplogroup-specific variants may not play an important role in the phenotypic expression of the T14484C mutation in those Chinese families with low penentrace of vision loss. However, nuclear modifier genes and environmental factors appear to be modifier factors for the phenotypic manifestation of the T14484C mutation in these Chinese families. [Copyright &y& Elsevier]

Abstract: This study investigated whether adolescent guinea pigs can develop myopia induced by negative lenses, and whether they can recover from the induced myopia. Forty-nine pigmented guinea pigs (age of 3 weeks) were randomly assigned to 4 groups: 2-week defocus (n =16), 4-week defocus (n =9), 2-week control (n =15) and 4-week control (n =9). A −4.00D lens was worn in the defocus groups and a plano lens worn in the control groups monocularly. The lenses were worn from 3 weeks to 5 weeks of age in the 2-week treatment groups with the biometry measured at 2, 4, 6, 10 and 14 days of lens wear. The lenses were worn from 3 weeks to 7 weeks of age in the 4-week treatment groups with the biometry measured immediately and at 2, 4, 6, 10 and 14 days after lens removal. Refractions in the defocused eyes developed towards myopia rapidly within 2 days of lens wear, followed by a slower development. The defocused eyes were at least 3.00D more myopic with a greater increase in vitreous length by 0.08mm compared to the fellow eyes at 14 days (p <0.05). The estimated choroidal thickness of the defocused eyes decreased rapidly within 2 days of lens wear, followed by a slower decrease over the next 4 days. Relative myopia induced by 4 weeks of negative-lens treatment declined rapidly following lens removal. A complete recovery occurred 14 days after lens removal when compared to the fellow controls. The refractive changes during the recovery corresponded to a slower vitreous lengthening and a rapid thickening of the choroid. The plano-lens wearing eyes showed a slight but significant myopic shift (<−0.80D) with no associated biometrical changes. Guinea pigs aged 3 weeks can still develop negative lens induced myopia and this myopia is reversible after removal of the lens. The myopia and recovery are mainly due to changes in vitreous length and choroidal thickness. [Copyright &y& Elsevier]

Purpose: To investigate the role of mitochondrial haplotypes in the development of Leber''s hereditary optic neuropathy (LHON) associated with the ND4 G11778A mutation in Chinese families. Design: Eight Han Chinese families with maternally transmitted LHON were studied using clinical, genetic, and molecular evaluations. Participants: One hundred sixty-seven subjects from 8 Chinese families with a wide age range and severity of visual impairment. Methods: All subjects underwent the clinical and genetic evaluation, as well as molecular analysis of mitochondrial DNA (mtDNA). Main Outcome Measures: The ophthalmologic examinations included visual acuity, visual field examination, visual evoked potentials, and fundus photography. Mitochondrial DNA analysis included the polymerase chain reaction amplification of the entire mtDNA and subsequent sequence determination. Results: Eight families exhibited extremely low penetrance of visual impairment, with the average of 13%. In particular, 14 (12 males and 2 females) of 119 matrilineal relatives in these families exhibited the variable severity and age at onset in visual dysfunction. The average age of onset of vision loss was 17 years. Molecular analysis of mtDNA identified the homoplasimic ND4 G11778A mutation and distinct sets of variants belonging to the Asian haplogroups M8a2, D4g2, B4a1c, B5b, N9a1, D4b2b, C, and M7b1. However, there was an absence of secondary LHON-associated mtDNA mutations in these 8 Chinese families. Conclusions: The extremely low penetrance of vision loss in these 8 Chinese pedigrees strongly indicates that the G11778A mutation was itself insufficient to produce a clinical phenotype. The absence of secondary LHON mtDNA mutations suggest that these mtDNA haplogroup-specific variants may not play an important role in the phenotypic expression of the G11778A mutation in those Chinese families with very low penentrace of vision loss. However, nuclear backgrounds and environmental factors seem to be modifying factors for the phenotypic manifestation of the G11778A mutation in these Chinese families. Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article. [Copyright &y& Elsevier]

Abstract: Purpose: To demonstrate that high-resolution biometry is possible in mouse eyes in vivo, using real-time OCT with focal plane advancement by a stepper motor. Methods: OCT images of eyes were taken from nine 29-day-old C57BL/6 mice(18 eyes) on two consecutive days. A custom-built real-time OCT instrument with a stepper motor was used to advance the focal plane from the corneal apex to the retina along the ocular axis. The ocular dimensions were determined by advancement of the stepper motor as it displayed on the OCT scan images. Results: OCT images of the entire eye, including the cornea, anterior chamber, lens, vitreous chamber, and retina, were successfully obtained from both eyes of all mice. The measured average corneal thickness from 18 eyes at the age of 29 days was 90.8±4.6μm, anterior chamber depth 707.4±21.4μm, lens thickness 1558.7±18.0μm, vitreous chamber depth 707.4±21.4μm and retinal thickness was 186.9±15.1μm. Total axial length (from the corneal apex to the nerve fiber layer of the retina) was 3003.3±44.1μm. None of them were significantly different if measured on two consecutive days, and no significant differences were found between measurements in the left and right eyes. Conclusion: By focal plane advancement of a real-time OCT instrument through the mouse eye, highly repeatable measurements of the ocular dimensions were obtained. This novel method may be used to study small animal models of normal and abnormal eye development. [Copyright &y& Elsevier]

Abstract: We report here the clinical, genetic and molecular characterization of one three-generation Han Chinese family with Leber’s hereditary optic neuropathy (LHON) and hearing loss. Four of 14 matrilineal relatives exhibited the moderate central vision loss at the average age of 12.5 years. Of these, one subject exhibited both LHON and mild hearing impairment. Sequence analysis of the complete mitochondrial genomes in the pedigree showed the presence of homoplasmic LHON-associated ND6 T14484C mutation, deafness-associated 12S rRNA A1555 mutation and 47 other variants belonging to Eastern Asian haplogroup H2. None of other mitochondrial variants was evolutionarily conserved and functional significance. Therefore, the coexistence of the A1555G mutation and T14484C mutations in this Chinese family indicate that the A1555G mutation may play a synergistic role in the phenotypic manifestation of LHON associated ND6 T14484C mutation. However, the incomplete penetrance of vision and hearing loss suggests the involvement of nuclear modifier genes and environmental factors in the phenotypic expression of these mtDNA mutations. [Copyright &y& Elsevier]

Purpose: This study used two-dimensional gel electrophoresis (2-DE) to analyze protein profiles for normal human scleral fibroblasts in order to provide a baseline for future study of proteomics of the sclera in experimental conditions. In addition, differences in the presence and amount of proteins from fibroblasts isolated from the anterior or posterior sclera were analyzed. Methods: The fibroblasts from anterior and posterior sclera of two healthy donors were cultured separately. Proteins were extracted from the cell lines, run on 2-DE, and stained by Commassie blue R-250. The gel images were analyzed to detect differences in expression levels (at least a fivefold difference in intensity) and location of the protein spots between the anterior and posterior sclera. These protein spots were trimmed from the gels, digested with trypsin, identified by MALDI mass spectrometry, and functionally categorized with human cDNA and protein databases from NCBI. Results: The number of spots detected was 455 and 453 protein spots from the anterior and posterior scleral fibroblasts, respectively. The patterns of gel maps were very similar between the anterior and posterior sclera in each donor and between the donors in either the anterior or posterior sclera. Nine proteins showed a stronger expression in the anterior sclera compared with the posterior sclera. These proteins together with the two proteins that appeared only in the anterior sclera were mainly associated with anabolic metabolism in cells. Eight proteins showed a stronger expression in the posterior sclera, and seven of them were mainly associated with catabolic metabolism in cells. Among all 19 protein spots identified as being differentially expressed between fibroblasts originally isolated from the anterior or posterior sclera, 14 proteins had a pI (3.86-7.95) and molecular weight (23-66 kDa) consistent with those found in human from the database of NCBI and from SwissProt Entry Name. Conclusions: The distribution and levels of expression in proteins are very similar for both the anterior and posterior sclera in vitro, with only approximately 4% of the proteins demonstrating a differential level of expression (at least fivefold) between the two segments of the sclera. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Guinea pigs have been increasingly used as an animal model for experimental myopia. Infant guinea pigs are susceptible to recovery from myopia within 2weeks of form deprivation. This study investigated whether adolescent guinea pigs are susceptible to recovery from myopia after a longer period of form deprivation. Method: Twenty-two guinea pigs (age of 3weeks) were randomly assigned to two groups: MDF (monocularly deprived facemask, n =11) and normal control (free of form deprivation, n =11). All animals underwent biometric measurement (refraction, corneal curvature and axial length) prior to the experiment. Animals in the MDF group wore a facemask that covered the right eye for 4weeks. The MDF was then removed and biometric measurement was performed immediately and at 2, 6, 10 and 14days. The same measurement was performed in the normal control group at time-points matching those of the MDF group. Results: The MDF eyes were approximately 4D more myopic with a greater increase in vitreous length by 0.12mm compared to either the fellow or the normal control eyes after form deprivation (p <0.01). This relative myopia shifted rapidly towards hyperopia within 2days after removal of the MDF, followed by a more gradual recovery. A complete recovery occurred by 6days after removal of the MDF compared to the fellow and normal control eyes (p >0.05). Vitreous length in the MDF eyes slightly reduced within 2days after removal of the MDF and then remained steady. The MDF eyes were similar to both the fellow and normal control eyes in vitreous length (p >0.05) 6days after removal of the MDF. There was no significant difference between the MDF, fellow and normal control eyes in the other axial components during the form deprivation and recovery period. Conclusion: Adolescent guinea pigs are susceptible to recovery from MDF-induced myopia. The refractive recovery is mainly correlated to the inhibited axial elongation of the vitreous chamber of the previously deprived eyes. [Copyright &y& Elsevier]

Abstract: Purpose: This study investigated changes in refraction, corneal curvature, axial components and weight of posterior sclera in guinea pig eyes during the normal development from birth. Methods: Sixty-four guinea pigs were assigned to eight groups (n =8 each). Each group underwent a series of ocular measurements at one of the eight time-points (0, 1, 2, 3, 5, 7, 9 and 11 weeks), including refraction (streak retinoscopy), corneal radius of curvature (CRC; keratometry), anterior segment length (AS: corneal thickness and depth of the anterior chamber), thickness of the crystalline lens (CL), vitreous chamber length (VC; all A-scan ultrasonography) and dry weight of a circular 6mm diameter punch in the posterior sclera (electronic balance). Results of all the measurements were statistically compared between right eye and left eye, male and female and among different age groups. Artifacts of retinoscopy due to small eye artifact were also estimated at different ages. Results: The refraction in guinea pig eyes was +5.22±0.23D (Mean, SE) at birth. This value decreased rapidly during the first 3 weeks followed by a slow decline. The overall decrease in refraction was highly significant from birth to 11 weeks (p <0.001 one way ANOVA). The small eye artifact was approximately 4.00D at birth, which reduced to 2.76D at 11 weeks. The guinea pig eyes were emmetropic by 3 weeks of age when the small eye artifact was taken into account. The CRC (3.24±0.01mm at birth), AS (1.20±0.01mm at birth), CL (2.72±0.03mm at birth) and VC (3.28±0.01mm at birth) increased within the first 3 weeks despite a transient decrease in the CRC within the first week. The increase in CRC, CL and VC continued after 3 weeks, however, the AS remained constant after this age. The increase in VC was better correlated to the decline of hyperopia (R 2 =0.70) than the other components (R 2 =0.33–0.39). Dry weight of the posterior sclera increased linearly from birth (p <0.001 between any two close time-points from 3 to 9 weeks) and had a moderately linear correlation with the VC (R 2 =0.60). There were no significant differences between the right eye and left eye or between male and female in all the measurements. Conclusions: In guinea pigs, the hyperopia present at birth rapidly reduces to emmetropia within the first 3 weeks of age. The emmetropization process in guinea pigs is mainly related to the increase in the vitreous chamber length. This relationship in guinea pigs is similar to that in chickens, tree shrews, primates and humans. The axial development of the vitreous chamber in guinea pigs appears to be associated with tissue growth of the posterior sclera. [Copyright &y& Elsevier]

Purpose : The aim of this study was to identify the presence of muscarinic acetylcholine receptors (mAChRs) in human sclera in order to determine whether the sclera is a potential site of action for mAChR antagonists. Methods : Cell lines of human scleral fibroblasts were cultured in Dulbecco modified Ealge's medium. Reverse transcription–polymerase chain reaction (RT-PCR) and Northern blot analysis were used to detect mRNA expression of muscarinic acetylcholine receptors in the cell lines of the fibroblasts. Western blot analysis and immunocytochemistry were used to detect proteins of mAChRs in the cell lines. Immunohistochemical study was used to further detect the presence of mAChR proteins in the frozen scleral sections. Results : The cultured fibroblasts demonstrated mRNA expression of five mAChRs (m1 to m5) in RT-PCR and Northern blot analysis. The molecular size of mRNA expression was largest for the m3 receptor, followed by the m2, m4, m5, and m1 in both RT-PCR and Northern blot analysis. Proteins of the m1 to m5 receptors were present in cell line fibroblasts under Western blot analysis and immunocytochemistry with a range of molecular weight from 80 kDa (m5) to 60 kDa (m1) in Western blot analysis. The presence of these five receptors was also detected in scleral tissues with immunohistochemistry. Conclusions : This study demonstrated the presence of mAChR subtypes (m1 to m5) in human scleral fibroblasts at both mRNA and protein levels. This finding indicates that the sclera is a potential site of action for the currently used mAChR antagonists in prevention of human myopia. [ABSTRACT FROM AUTHOR]

Abstract: This study evaluated the efficacy of a facemask, a non-invasive and potentially more reliable method, in inducing axial myopia in guinea pigs. Thirty-six animals were randomly assigned to 3 groups: MDF (monocularly-deprived facemask, n=6), lid-suture (eyelids sutured monocularly, n=24) and normal control (free of form deprivation, n=6). All the groups underwent biometric measurement (refraction, corneal curvature and axial length) prior to the experiment. All animals in the MDF group underwent biometric measurement at each of the 4 timepoints (2, 4, 6 and 8 weeks of form deprivation). In the lid-sutured group, the animals were randomly assigned to 4 subgroups (n=6 each) and each subgroup underwent biometric measurement at one of the timepoints matching those of the MDF group. In the normal control group, all animals underwent biometric measurement at each of the timepoints matching those of the 2 experimental groups. Placement of a facemask on an animal took approximately 10sec and all the facemasks remained in place at all timepoints. The procedure of lid-suture took at least 20min for an animal and rupture of the sutures occurred in 50% of the animals after 4 weeks. The MDF eyes developed myopia from −2.21±2.11D (Mean±s.d.) at 2 weeks to −4.38±2.14 at 8 weeks (p<0.05 at all timepoints, compared to the contralateral eyes) with a lengthening of the vitreous chamber from 0.17±0.05mm at 2 weeks to 0.29±0.12mm at 8 weeks (p<0.01 at all timepoints, compared to the contralateral eyes). The lid-sutured eyes developed myopia from −2.38±1.21D at 2 weeks to −4.75±1.39D at 8 weeks (p<0.05 at all timepoints, compared to the contralateral eyes) with a lengthening of the vitreous chamber from 0.13±0.02mm at 2 weeks to 0.30±0.10mm at 8 weeks (p<0.05 at 2, 4, 8 weeks, but >0.05 at 6 weeks, compared to the contralateral eyes) and an increase in the radius of the corneal curvature (0.20±0.07mm at 4 weeks, p<0.01; 0.17±0.05mm at 8 weeks, p<0.05; compared to the contralateral eyes). Both the MDF and lid-sutured groups had a similar development in myopia and vitreous length (MDF vs lid-suturing: p>0.05 at all timepoints, one-way ANOVA with Bonferroni correction). This development was significantly faster than in the normal control group (MDF or lid-suture vs normal control: p<0.05 to <0.01 from 2 to 8 weeks, one-way ANOVA with Bonferroni correction). The radius of corneal curvature in the lid-sutured group was significantly greater than in either the MDF group or the normal control group since 4 weeks of form deprivation (p<0.05, one-way ANOVA with Bonferroni correction). Treatment with MDFs is as effective as the lid-suture in inducing axial myopia in guinea pigs. This method is non-invasive and allows evaluation of the same group of animals at different timepoints so that the number of animals required could be minimized without affecting the accuracy of the results. [Copyright &y& Elsevier]

Abstract: We report here the clinical, genetic, and molecular characterization of five Chinese families with Leber’s hereditary optic neuropathy (LHON). Clinical and genetic evaluations revealed the variable severity and age-of-onset in visual impairment in these families. Strikingly, there were extremely low penetrances of visual impairment in these Chinese families. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the distinct sets of mtDNA polymorphism, in addition to the identical ND4 G11696A mutation associated with LHON. Indeed, this mutation is present in homoplasmy only in the maternal lineage of those pedigrees but not other members of these families. In fact, the occurrence of the G11696A mutation in these several genetically unrelated subjects affected by visual impairment strongly indicates that this mutation is involved in the pathogenesis of visual impairment. Furthermore, the N405D in the ND5 and G5820A in the tRNACys, showing high evolutional conservation, may contribute to the phenotypic expression of G11696A mutation in the WZ10 pedigree. However, there was the absence of functionally significant mtDNA mutations in other four Chinese pedigrees carrying the G11696A mutation. Therefore, nuclear modifier gene(s) or environmental factor(s) may play a role in the phenotypic expression of the LHON-associated G11696A mutation in these Chinese pedigrees. [Copyright &y& Elsevier]

Abstract: We have used carbocyanine dye tracing from the brachium of the superior colliculus in conjunction with Nissl staining and immunohistochemistry to GAP-43 and calretinin to study the development of retinal projections to the superior colliculus in 17 human embryos and fetuses aged from 8 to 28 weeks. Lamination of the superior colliculus begins to emerge by 11 weeks, and by 16 weeks all seven layers of the mature superior colliculus are visible. Fibres immunoreactive to GAP-43 were seen at 13 weeks in the most superficial layers. By 19 weeks, GAP-43 immunoreactivity was present in the stratum opticum as well as the deeper fibres layers, indicating the development of fibre pathways following those laminae. Carbocyanine dye tracing of retinocollicular projections showed extensive rostrocaudally running unbranched fibres in the superficial superior colliculus at 12 weeks. Shortly after this (13 weeks), retinocollicular fibres penetrate the deeper collicular layers and branching becomes apparent. We also saw occasional retrogradely labelled somata following DiI insertion into the superior brachium. Our findings indicate that development of the human superior colliculus and its connections is largely complete by 20 weeks. This would suggest that functional capacity of the human superior colliculus should also be mature by the middle of gestation. [Copyright &y& Elsevier]

Abstract: We report here the clinical, genetic, and molecular characterization of three Chinese families (WZ4, WZ5, and WZ6) with Leber’s hereditary optic neuropathy (LHON). Clinical and genetic evaluations revealed the variable severity and age-of-onset in visual impairment in these families. Penetrances of visual impairment in these Chinese families were 33.3%, 35.7%, and 35.5%, respectively, with an average 34.8%. Furthermore, the average age-at-onset in those Chinese families was 17, 20, and 18 years. In addition, the ratios between affected male and female matrilineal relatives in these Chinese families were 3:0, 1:1, and 1.2:1, respectively. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the distinct sets of mtDNA polymorphism, in addition to the identical G11778A mutation associated with LHON in many families. The fact that mtDNA of those pedigrees belonged to different haplogroups F1, D4, and M10 suggested that the G11778A mutation occurred sporadically and multiplied through evolution of the mtDNA in China. However, there was the absence of functionally significant mutations in tRNA and rRNAs or secondary LHON mutations in these Chinese families. The I187T mutation in the ND1, the S99A mutation in the A6, the V254I in CO3, and I58V in ND6 mutation, showing high evolutional conservation, may contribute to the phenotypic expression of the G11778A mutation in the WZ6 pedigree. By contrast, none of mtDNA variants are evolutionarily conserved and implicated to have significantly functional consequence in WZ4 and WZ5 pedigrees. Apparently, these variants do not have a potential modifying role in the development of visual impairment associated with G11778A mutation in those two families. Thus, nuclear modifier gene(s) or environmental factor(s) seem to account for the penetrance and expressivity of LHON in these three Chinese families carrying the G11778A mutation. [Copyright &y& Elsevier]

The embryonic and fetal development of the nuclear components and pathways of vagal sensorimotor circuits in the human has been studied using Nissl staining and carbocyanine dye tracing techniques. Eight fetal brains ranging from 8 to 28 weeks of development had DiI (1,1′-dioctadecyl-3,3,3′,3′ tetramethylindocarbocyanine perchlorate) inserted into either the thoracic vagus nerve at the level of the sternal angle (two specimens of 8 and 9 weeks of gestation) or into vagal rootlets at the surface of the medulla (at all other ages), while a further five were used for study of cytoarchitectural development. The first central labeling resulting from peripheral application of DiI to the thoracic vagus nerve was seen at 8 weeks. By 9 weeks, labeled bipolar cells at the ventricular surface around the sulcus limitans (sl) were seen after DiI application to the thoracic vagus nerve. Subnuclear organization as revealed by both Nissl staining and carbocyanine dye tracing was found to be advanced at a relatively early fetal age, with afferent segregation in the medial Sol apparent at 13 weeks and subnuclear organization of efferent magnocellular divisions of dorsal motor nucleus of vagus nerve noticeable at the same stage. The results of the present study also confirm that vagal afferents are distributed to the dorsomedial subnuclei of the human nucleus of the solitary tract, with particular concentrations of afferent axons in the gelatinosus subnucleus. These vagal afferents appeared to have a restricted zone of termination from quite early in development (13 weeks) suggesting that there is no initial exuberance in the termination field of vagal afferents in the developing human nucleus of the solitary tract. On the other hand, the first suggestion of afferents invading 10N from the medial Sol was not seen until 20 weeks and was not well developed until 24 weeks, suggesting that direct monosynaptic connections between the sensory and effector components of the vagal sensorimotor complex do not develop until this age. [Copyright &y& Elsevier]

In this work, seeded dispersion polymerization was adopted to prepare anisotropic silica/polymer composite particles with controllable sizes and morphologies using the surface-modified silica particles as the seeds. Through this approach, submicron-sized silica/polymer particles with snowman-like, dumbbell-like, raspberry-like and core-shell structures could be easily fabricated in large scale. Many factors that might affect the morphologies of composite particles including the weight ratio of monomer/silica seeds, the polarity of reaction medium, reaction temperature, reaction time, the amount of crosslinking agent or the polarity of monomers were investigated. The results indicate that the interfacial tension between PS phases and SiO 2 particles and the coalescence between growing polymer nodules over silica particles are responsible for the formation of different particle morphologies. It is interesting that snowman-like SiO 2 /PS particles could be afforded by two different processes: one was normally transformed from raspberry-like particles via the coalescence between growing polymer nodules; the other was formed directly at a high content of monomer. These different morphological particles may have important applications in biological/medical materials, optical materials, sensors, catalyst support, colloidal stabilizer, etc. [ABSTRACT FROM AUTHOR]

Purpose: The most likely etiology of post-LASIK dry eye is corneal nerve damage; however, no direct relationship between post-LASIK dry eye symptoms and nerve damage has been established, and limited information is available about the relationship between dry eye signs and corneal reinnervation after LASIK. Tear neuropeptides (SP and CGRP) are important in the maintenance of corneal nerve health, but the impact of LASIK has not yet been studied. This study evaluated changes in nerve morphology, tear neuropeptide, and dry eye, so as to establish the relationship between reinnervation and dry eye and to assess the role of tear neuropeptides in reinnervation post-LASIK. Methods: Twenty non-dry eye volunteers who had undergone bilateral myopic-LASIK completed this study. Corneal nerve morphology (density, width, interconnections, and tortuosity), SP and CGRP concentration, and dry eye were monitored over time prior to, 1 day, 1 week, 1, 3, and 6 months post-LASIK. Results: Dry eye symptoms and tear function, except for osmolarity ( P = 0.003), remained unchanged post-LASIK. Corneal nerve morphology decreased immediately, and did not return to preoperative levels by 6 months post-LASIK ( P < 0.001). Increased tear SP concentration was observed 3 months post-LASIK ( P < 0.001). Associations between reinnervation as measured by increased density and lower tear SP ( P = 0.03), and between increased density and decreased dry eye symptoms ( P = 0.01) were found post-LASIK. Conclusion: An inverse relationship between reinnervation post-LASIK and dry eye symptoms was found, confirming that post-LASIK dry eye is a neuropathic disease. This study is the first to demonstrate an association between tear SP and post-LASIK reinnervation, suggesting that strategies for manipulating neuropeptide concentration to improve reinnervation may improve ocular comfort post-LASIK. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

Pathological myopia (PM) is the leading ocular disease for impaired vision worldwide. Clinically, the characteristics of pathology distribution in PM are global-local on the fundus image, which plays a significant role in assisting clinicians in diagnosing PM. However, most existing deep neural networks focused on designing complex architectures but rarely explored the pathology distribution prior of PM. To tackle this issue, we propose an efficient pyramid channel attention (EPCA) module, which fully leverages the potential of the clinical pathology prior of PM with pyramid pooling and multi-scale context fusion. Then, we construct EPCA-Net for automatic PM recognition based on fundus images by stacking a sequence of EPCA modules. Moreover, motivated by the recent pretraining-and-finetuning paradigm, we attempt to adapt pre-trained natural image models for PM recognition by freezing them and treating the EPCA and other attention modules as adapters. In addition, we construct a PM recognition benchmark termed PM-fundus by collecting fundus images of PM from publicly available datasets. The comprehensive experiments demonstrate the superiority of EPCA-Net over state-of-the-art methods in the PM recognition task. For example, EPCA-Net achieves 97.56% accuracy and outperforms ViT by 2.85% accuracy on the PM-fundus dataset. The results also show that our method based on the pretraining-and-finetuning paradigm achieves competitive performance through comparisons to part of previous methods based on traditional fine-tuning paradigm with fewer tunable parameters, which has the potential to leverage more natural image foundation models to address the PM recognition task in limited medical data regime. • We propose the EPCA module to explore distribution prior of PM. • We adapt pre-trained models to PM recognition with pretraining-and-finetuning paradigm. [ABSTRACT FROM AUTHOR]

Purpose: Whether there is an interaction between eyes of individual subjects in refractive development is an important issue to guide experimental designs and help understand mechanisms involved in development of refractive errors. This study investigated whether spontaneous high myopia in one eye will affect refractive development of the fellow eye treated with form deprivation. Methods: Thirty-four guinea pigs were divided into four groups: MD (monocularly form-deprived animals with a pre-treatment anisometropia ≤≤ 2D, n == 8), anisometropic MD (monocular form deprivation on a relatively hyperopic eye in animals with a pre-treatment anisometropia ≥≥ 10D, n == 9), normal control (non-form deprivation in animals with a pre-treatment anisometropia ≤≤ 2D, n == 8), and anisometropic control (non-form deprivation in animals with a pre-treatment anisometropia ≥≥ 10D, n == 9). All eyes in different groups underwent biometric measurements on days 0, 12, 24, and 36 of the experiment. Results: High myopia in one eye reduced form deprivation myopia in the fellow treated eye. The change in refraction from 0 to 36 days in the deprived eyes was -3.07D for the MD group, but -1.22D for the anisometropic MD group (-3.07D vs. -1.22D: p == 0.009, independent sample t-test). The amount of vitreous chamber lengthening over the same period in the deprived eyes was 0.19 mm for the MD group, but 0.12 mm for the anisometropic MD group (0.19 mm vs. 0.12 mm: p == 0.038, independent sample t-test). Myopic development in the anisometropic animals is mainly inhibited within the first 12 days compared to normal MD animals. Conclusions: These results indicate that an interaction in refractive development may exist temporarily between two eyes of a highly anisometropic animal if the visual environment has been changed. [ABSTRACT FROM AUTHOR]

Abstract: We report here the clinical, genetic, and molecular characterization of five Han Chinese families with Leber’s hereditary optic neuropathy (LHON). Strikingly, there were very low penetrances of visual impairment in these Chinese families, ranging from 4.2% to 22.2%, with an average of 10.2%. In particular, only 7 (4 males/3 females) of 106 matrilineal relatives in these families exhibited the variable severity and age-at-onset in visual dysfunction. The age-at-onset for visual impairment in matrilineal relatives in these families, varied from 20 to 25years, with an average of 21.8years old. Molecular analysis of mitochondrial genomes identified the homoplasmic ND1 G3460A mutation and distinct sets of variants, belonging to the Asian haplogroups B5b, C4a1, D5, F1, and R9, respectively. This suggests that the G3640A mutation occurred sporadically and multiplied through evolution of the mtDNA in China. However, there was the absence of known secondary LHON-associated mtDNA mutations in these Chinese families. Very low penetrance of visual loss in these five Chinese pedigrees strongly indicated that the G3640A mutation was itself insufficient to develop the optic neuropathy. The absence of secondary LHON mtDNA mutations suggest that these mtDNA haplogroup-specific variants may not play an important role in the phenotypic expression of the G3640A mutation in those Chinese families with low penetrance of vision loss. However, nuclear modifier genes, epigenetic and environmental factors appear to be modifier factors for the phenotypic manifestation of the G3640A mutation in these Chinese families. [Copyright &y& Elsevier]

Abstract: We report here the clinical, genetic, and molecular characterization of three Chinese families with Leber’s hereditary optic neuropathy (LHON). There were variable severity and age of onset in visual impairment among these families. Strikingly, there were extremely low penetrances of visual impairment in these Chinese families. Sequence analysis of complete mitochondrial genomes in these pedigrees showed the homoplasmic T14502C (I58V) mutation, which localized at a highly conserved isoleucine at position 58 of ND6, and distinct sets of mtDNA polymorphisms belonging to haplogroups M10a, F1a1, and H2. The occurrence of T14502C mutation in these several genetically unrelated subjects affected by visual impairment strongly indicates that this mutation is involved in the pathogenesis of visual impairment. Here, mtDNA variants I187T in the ND1, A122V in CO1, S99A in the A6, and V254I in CO3 exhibited an evolutionary conservation, indicating a potential modifying role in the development of visual impairment associated with T14502C mutation in those families. Furthermore, nuclear modifier gene(s) or environmental factor(s) may play a role in the phenotypic manifestation of the LHON-associated T14502C mutation in these Chinese families. [Copyright &y& Elsevier]

Abstract: The dorsal nucleus of the vagus nerve plays an integral part in the control of visceral function. The aim of the present study was to correlate structural and chemical changes in the developing nucleus with available data concerning functional maturation of human viscera and reflexes. The fetal development (ages 9 to 26 weeks) of the human dorsal nucleus of the vagus nerve has been examined with the aid of Nissl staining and immunocytochemistry for calbindin and tyrosine hydroxylase. By 13 weeks, the dorsal vagal nucleus emerges as a distinct structure with at least two subnuclei visible in Nissl stained preparations. By 15 weeks, three subnuclei (dorsal intermediate, centrointermediate and ventrointermediate) were clearly discernible at the open medulla level with caudal and caudointermediate subnuclei visible at the level of the area postrema. All subnuclei known to exist in the adult were visible by 21 weeks and cytoarchitectonic differentiation of the nucleus was largely completed by 25 weeks. The adult distribution pattern of calbindin and tyrosine hydroxylase immunoreactive neurons was also largely completed by 21 weeks, although morphological differentiation of labeled neurons continued until the last age examined (26 weeks). The structural development of the dorsal nucleus of the vagus nerve appears to occur in parallel with functional maturation of the cardiovascular and gastric movements, which the nucleus controls. [Copyright &y& Elsevier]

Abstract: We report here the clinical, genetic, and molecular characterization of one Han Chinese family with maternally transmitted Leber’s hereditary optic neuropathy (LHON). Three of seven matrilineal relatives in this family exhibited the variable degree of central vision loss at the age of 12, 14, and 16 years old, respectively. Sequence analysis of the complete mitochondrial DNA in this pedigree revealed the presence of the ND1 G3460A mutation and 47 other variants, belonging to the Asian haplogroup M7b2. The G3460A mutation is present at homoplasmy in matrilineal relatives of this Chinese family. Of other variants, the homoplasmic A14693G mutation is of special interest as it was implicated to be associated with other mitochondrial disorders. This mutation is located at the TψC-loop, at conventional position 54 of tRNAGlu. The uridine at this position (U54), which is highly conserved from bacteria to human mitochondria, has been implicated to be important for tRNA structure and function. Thus, the A14693G mutation may alter the tertiary structure of this tRNA, cause a failure in this tRNA metabolism, thereby worsening the mitochondrial dysfunction associated with the primary G3460A mutation. Therefore, the tRNAGlu A14693G mutation may have a potential modifier role in the phenotypic manifestation of the primary LHON-associated G3460A mutation in this Chinese family. [Copyright &y& Elsevier]

Abstract: We report here the characterization of a four-generation Han Chinese family with Leber’s hereditary optic neuropathy (LHON). This Chinese family exhibited a variable severity and age-at-onset of visual loss. Notably, the average age-at-onset of vision impairment changed from 26years (generation III) to 14years (generation IV), with the average of 18years in this family. In addition, 30% and 50% of matrilineal relatives in generation III and IV of this family developed visual loss with a variability of severity, ranging from blindness to normal vision. Sequence analysis of the complete mitochondrial DNA in this pedigree revealed the presence of the homoplasmic ND4 G11778A mutation and 33 other variants, belonging to the Asian haplogroup D4. Of other variants, the homoplasmic G11696A mutation in the ND4 gene is of special interest as it was implicated to be associated with LHON in a large Dutch family and five Chinese pedigrees with extremely penetrance of visual loss. In fact, the G11696A mutation caused the substitution of an isoleucine for valine at amino acid position 313, located in a predicted transmembrane region of ND4. These imply that the G11696A mutation may act in synergy with the primary LHON-associated G11778A mutation in this Chinese pedigree. [Copyright &y& Elsevier]

Abstract: We report here the clinical, genetic, and molecular characterization of three Chinese families with maternally transmitted Leber’s hereditary optic neuropathy (LHON). Clinical and genetic evaluations revealed the variable severity and age-of-onset in visual impairment in these families. In the affected matrilineal relatives, the loss of central vision is bilateral, the fellow eye becoming affected either simultaneously (45%) or sequentially (55%). The penetrances of vision loss in these pedigrees were 27%, 50%, and 60%, respectively. The age-at-onset of vision loss in these families was 14, 19, and 24 years, respectively. Furthermore, the ratios between affected male and female matrilineal relatives were 1:1, 1:1.2, and 1:2, respectively. Mutational analysis of mitochondrial DNA revealed the presence of homoplasmic ND6 T14484C mutation, which has been associated with LHON. The incomplete penetrance and phenotypic variability implicate the involvement of nuclear modifier gene(s), environmental factor(s) or mitochondrial haplotype(s) in the phenotypic expression of the LHON-associated T14484C mutation in these Chinese pedigrees. [Copyright &y& Elsevier]

Abstract: The present study investigated the prenatal development of the cyto- and chemoarchitecture of the human nucleus of the solitary tract from 9 to 35weeks, by using Nissl staining and immunoreactivity to calbindin, calretinin, tyrosine hydroxylase and GAP-43. The nucleus began to gain heterogeneity and show different subnuclei as early as 13weeks, and approached cytoarchitectural maturation from 21 to 25weeks. The subnuclear division pattern observed in the fetal nucleus of the solitary tract at 25weeks was very similar to that of the adult. Neurons immunoreactive to calbindin first appeared in the medial gastrointestinal area of the nucleus at 13weeks, particularly within a putative gelatinosus subnucleus, while calretinin immunoreactivity during fetal life suggested the possible presence of a central subnucleus. Tyrosine hydroxylase immunoreactive neurons were seen in the medial subdivisions of the nucleus of the solitary tract as early as 13weeks, but the population continued to increase until 25weeks. Strong GAP-43 immunoreactivity was also present in the nucleus of the solitary tract at 13weeks, especially in the dorsolateral and commissural subnuclei, while at 21weeks there was a significant decline of GAP-43 expression. Results from the chemoarchitectural study showed that the human nucleus of the solitary tract expressed various neurochemical substances at an early developmental age (13weeks), even before cellular and neuropil maturation was fully attained. Expression of these factors may play an important role in establishment and integration of viscerosensory function in the nucleus. [Copyright &y& Elsevier]

Abstract: We report here the characterization of a three-generation Han Chinese family with Leber''s hereditary optic neuropathy (LHON). This Chinese family exhibited high penetrance and expressivity of visual impairment. The average age-of-onset was 19 years in this family. All male and 33% female matrilineal relatives in this Chinese family developed visual loss with a wide range of severity, ranging from blindness to normal vision. Sequence analysis of the complete mitochondrial DNA in this pedigree revealed the presence of the ND4 G11778A mutation and 40 other variants, belonging to the Asian haplogroup D4. The G11778A mutation is present at homoplasmy in matrilineal relatives of this Chinese family. Of other variants, the homoplasmic A15951G mutation is of special interest as it is located adjacent to 3′ end, at conventional position 71 of tRNAThr. The adenine (A71) at this position of tRNAThr, highly conserved from bacteria to human mitochondria, has been implicated to be important for tRNA identity and pre-tRNA processing. In fact, the significant reduction of the steady-state levels in tRNAThr was observed in cells carrying both the A15951G and G11778A mutations but not cells carrying only G11778A mutation. Thus, the A15951G mutation most probably leads to a failure in mitochondrial tRNA metabolism, worsening the mitochondrial dysfunction associated with the primary G11778A mutation. These imply that the tRNAThr A15951G mutation may have a potential modifier role in increasing the penetrance and expressivity of the primary LHON-associated G11778A mutation in this Chinese family. [Copyright &y& Elsevier]

Purpose: To evaluate the relative proportion of conjunctival MUC5AC+ and MUC5AC− goblet cells in a post-LASIK population and their association with dry eye indicators and corneal nerve morphology using a MUC5AC+ Goblet Cell Index.Methods: Twenty subjects who had undergone LASIK > 12 months previously and 20 age-matched controls were recruited. Dry eye symptoms, tear breakup time, osmolarity, meniscus area and corneal nerve morphology were examined. Conjunctival impression cytology samples were collected from inferior-temporal bulbar conjunctiva using Millicell® inserts. Total goblet cell density was determined from positive cytokeratin-7 (CK7) immunolabelling; MUC5AC+ goblet cell density was determined from both CK7+- and MUC5AC+-immunolabelled cells. The ratio of MUC5AC+ to total density was defined as the “MUC5AC+ Goblet Cell Index”. Differences in variables between groups and the associations between goblet cell variables and clinical assessments were examined.Results: No significant differences in the total and MUC5AC+ goblet cell density and tear film parameters were found between groups, although greater ocular discomfort was reported in the post-LASIK group (P = 0.02). A higher MUC5AC+ Index was associated with worse/greater dry eye symptoms (ρ = 0.55, P = 0.01) and higher nerve tortuosity (ρ = 0.57, P = 0.01) in the post-LASIK group; lower nerve density and thickness was found in controls (ρ > −0.45, P < 0.05), but not associated with tear film parameters.Conclusions: The MUC5AC+ Goblet Cell Index provides an indicator of mucin secretion for assessing the goblet cell function in dry eye. In the post-LASIK participants, we found an increased MUC5AC+ Index associated with worse dry eye symptoms and adverse changes in corneal nerve morphology. [ABSTRACT FROM AUTHOR]

Abstract: Retinal arachidonic acid (ARA) levels in form‐deprived eyes decline in guinea pigs. As prostaglandin F2α (PGF2α) is an ARA metabolite and endogenous agonist of prostaglandin F receptor (FP), we have been suggested that down‐regulation of PGF2α‐FP receptor signalling pathway contributes to myopia onset. To test this hypothesis, this study determines whether: (i) retinal PGF2α levels decline during the development of form deprivation myopia (FDM) in guinea pigs; (ii) FP receptor agonism and antagonism alter emmetropization and myopia development. Pigmented guinea pigs were randomly assigned to normal vision and form‐deprived groups. Ultraperformance liquid chromatography coupled with a mass spectrometer (UPLC‐MS) measured retinal PGF2α levels 2 weeks after form deprivation (FD). The selective FP agonist, latanoprost acid (LAT) and its corresponding antagonist, AL8810, were peribulbarly injected into each group. An eccentric infrared photorefractor (EIR) monitored refraction. A‐scan ultrasonography measured axial elongation (AL) and vitreous chamber depth (VCD). Tonometry measured the intraocular pressure (IOP). Retinal PGF2α levels declined in form‐deprived eyes compared to those in normal eyes. Neither LAT nor AL8810 affected IOP with or without FD. On the other hand, after 4 weeks of daily 0.5 μg AL8810 treatment, a myopia of −1.99 ± 0.34 dioptre (D) developed, but LAT had no effect on emmetropization in a normal visual environment. Nevertheless, daily 30 μg LAT treatment for 4 weeks inhibited FDM development by 41% (vehicle control: −8.39 ± 0.45 D; LAT: −4.95 ± 0.39 D; two‐way anova with repeated measures, p < 0.05). Down‐regulation of PGF2α‐FP receptor signalling pathway may contribute to myopia onset as retinal PGF2α declined in myopic eyes and antagonism of FP receptor by AL8810 induced a myopic shift in normal vision environment. Meanwhile, up‐regulation of this pathway by LAT inhibited FDM development. However, the mechanism underlying LAT‐induced FDM inhibition needs further clarification. This uncertainty exists because its inhibition of FDM suggests that LAT strengthens the scleral framework which reduces axial elongation. On the other hand, its IOP‐lowering effect is attributed to thinning and weakening the scleral framework in glaucoma treatment. [ABSTRACT FROM AUTHOR]

In this study, we explored the predictive role of choroidal blood perfusion (ChBP) and choroidal thickness (ChT) on the development of myopia in guinea pigs. Optical Coherence Tomography Angiography (OCTA) was used to assess the baseline choroidal blood perfusion (ChBP) and choroidal thickness (ChT) in 4-week-old guinea pigs. Refraction and axial length (AL) were measured at baseline. Myopia was induced for one week using form-deprivation (FD) or negative lenses followed by measurements of refraction, axial length and choroidal parameters (ChT and ChBP). The correlations were evaluated between the baseline choroidal values and the magnitude of myopia induced, along with the magnitude of changes in ChT and ChBP after myopia induction. There was a significant correlation between the baseline choroidal parameters and ocular refraction. Myopia induction led to choroidal thinning and less ChBP as well as longer eyes. On the other hand, following exposure to the same non-obstructed visual induction period, the myopic shift was less, and it was associated with thicker choroids and more ChBP at baseline. One week of myopia induction also resulted in thinner choroids and less ChBP, and these declines also correlated with their baseline values. In conclusion, the present study shows that the changes in the baseline choroidal ChT and ChBP parameters are proportional to the magnitude of myopia development and axial elongation in guinea pigs. These significant correlations between baseline ChBP and ChT and myopia development suggest that they may be a viable predictor of this process in guinea pigs. • This study evaluates the possibility of choroidal blood perfusion (ChBP) as a predictor of myopia development in guinea pigs. • A tenable explanation is provided for why assessment of choroidal thickness (ChT) is indicative of myopia development. • Excellent correlations exist between baseline ChT and ChBP and magnitudes of myopia induction. [ABSTRACT FROM AUTHOR]

Leber's hereditary optic neuropathy (LHON) is one of the most common mitochondrial disorders. We report here the clinical, genetic and molecular analysis of mitochondrial DNA (mtDNA) in eight Han Chinese families carrying the known mitochondrial 11778G > A(MT-ND4) mutation. Thirty-seven (26 males/11 females) of 77 matrilineal relatives in these families exhibited the variable severity and age-at-onset of optic neuropathy. The penetrances were from 25% to 75%, with the average of 42%, and the age-at-onset for visual impairment varied from 10 to 25 years, with the average of 17 in these Chinese pedigrees. Molecular analysis of their mtDNA identified distinct sets of variants belonging to the Eastern Asian haplogroupD4j. Except the known m.11778G > A mutation, the m.11696G > A(MT-ND4) mutation caused the substitution of an isoleucine for valineat amino acid position 313, located in a predicted transmembrane region of ND4. And, it is reported that the m.11696G > A mutation was associated with LHON, and appeared to contribute to higher penetrance in these nine Chinese families than other Chinese families carrying only the m.11778G > A mutation. Therefore, the mitochondrial haplogroup D4j specific m.11696G > A mutation may act in synergy with the primary LHON-associated m.11778G > A mutation, thereby increasing the penetrance and expressivity of visual loss in these Chinese families. [ABSTRACT FROM PUBLISHER]

RNA-binding proteins (RBPs) bind at different positions of the pre-mRNA molecules to promote or reduce the usage of a particular exon. Seeking to understand the working principle of these positional effects, we develop a capture RIC-seq (CRIC-seq) method to enrich specific RBP-associated in situ proximal RNA-RNA fragments for deep sequencing. We determine hnRNPA1-, SRSF1-, and PTBP1-associated proximal RNA-RNA contacts and regulatory mechanisms in HeLa cells. Unexpectedly, the 3D RNA map analysis shows that PTBP1-associated loops in individual introns preferentially promote cassette exon splicing by accelerating asymmetric intron removal, whereas the loops spanning across cassette exon primarily repress splicing. These "positional rules" can faithfully predict PTBP1-regulated splicing outcomes. We further demonstrate that cancer-related splicing quantitative trait loci can disrupt RNA loops by reducing PTBP1 binding on pre-mRNAs to cause aberrant splicing in tumors. Our study presents a powerful method for exploring the functions of RBP-associated RNA-RNA proximal contacts in gene regulation and disease. [Display omitted] • CRIC-seq maps specific RBP-associated RNA-RNA spatial contacts • Positional rules of PTBP1-associated RNA loops in splicing regulation • PTBP1-associated intronic RNA loops facilitate asymmetrical intron removal • sQTLs disrupt PTBP1-associated RNA loops to promote tumor cell growth Ye et al. have developed a new method, named CRIC-seq, for the global profiling of PTBP1-associated RNA-RNA spatial contacts. The authors unravel the positional mechanisms by which PTBP1-associated RNA loops enhance or repress splicing, demonstrating that cancer-related splicing quantitative trait loci can disrupt PTBP1-associated RNA loops to promote tumor cell growth. [ABSTRACT FROM AUTHOR]

The association between near work activities and myopia has not been clearly established. This study establishes a model for near work myopia (NWM) induced by short viewing distance in guinea pigs with a carefully controlled visual environment, and evaluates the effect of viewing distance in myopia development. Pigmented guinea pigs (3 weeks old) were randomly assigned to 3 groups: near work (NW)-, form-deprivation (FD)-, and -4D hyperopic-defocus (HD)-induced myopia. Animals in NW groups were kept in cylindrical cages with vertical square-wave gratings, providing short- (S, d = 18 cm), middle- (M, d = 44 cm), and long- (L, d = 88 cm) mean viewing distances, all at the same illuminance, during daily treatment for 14 days. Biometric parameters, including refraction, anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and axial length (AL), were measured at the beginning and end of 14 days' treatment. Choroidal thickness (ChT) and choroidal blood perfusion (ChBP) were measured by optical coherence tomography (OCT) and OCT-angiography (OCTA), respectively, at the end of treatment. Refraction was shifted towards myopia in the S-cage group, compared with the M- and L-cage groups; refractions in the L-, M- and S-cage groups were 5.19 ± 0.65 D, 4.30 ± 0.64 D, and 0.53 ± 0.61 D, respectively (p < 0.001). VCD and AL in the S-cage group increased in parallel with the myopic shift (L vs M vs S: VCD: 3.15 ± 0.02 mm vs 3.17 ± 0.02 mm vs 3.26 ± 0.02 mm, p < 0.001; AL: 7.99 ± 0.03 mm vs 8.03 ± 0.03 mm vs 8.15 ± 0.02 mm, p = 0.001). In FD and HD eyes, changes similar to those in the S-cage group (near-work group, NW) were seen in refraction (NW vs FD vs HD: 5.36 ± 0.82 D vs −5.78 ± 0.44 D vs −4.96 ± 0.54 D, p = 0.734), ACD, LT, VCD and AL. Also, ChT and ChBP were significantly less in the S-cage group than in the M- and L-cage groups after 14 days' treatment (L vs M vs S: ChT: 74.84 ± 3.27 vs 76.07 ± 3.49 vs 61.95 ± 3.31, P = 0.002; ChBP: 48.32 ± 2.23 vs 48.66 ± 2.30 vs 38.14 ± 2.06, p = 0.002). Rearing in S-cages induced myopia in guinea pigs and correspondingly decreased ChBP and ChT. The present study provides objective evidence that short viewing distance could be a risk factor for myopia, and describes a useful model for studying the underlying mechanisms. • This study establishes a novel near work myopia animal model in guinea pigs. • Short viewing distance induces myopia in guinea pigs. • Myopia induced by short viewing distance is similar to that induced by form deprivation/defocus. • Short viewing distance decreases choroidal blood perfusion and choroidal thickness. [ABSTRACT FROM AUTHOR]

Myopia incidence in China is rapidly becoming a very serious sight compromising problem in a large segment of the general population. Therefore, delineating the underlying mechanisms leading to myopia will markedly lessen the likelihood of other sight compromising complications. In this regard, there is some evidence that patients afflicted with familial adenomatous polyposis (FAP), havean adenomatous polyposis coli (APC) mutation and a higher incidence of myopia. To clarify this possible association, we determined whether the changes in pertinent biometric and biochemical parameters underlying postnatal refractive error development in APCMin mice are relevant for gaining insight into the pathogenesis of this disease in humans. The refraction and biometrics in APCMin mice and age-matched wild-type (WT) littermates between postnatal days P28 and P84 were examined with eccentric infrared photorefraction (EIR) and customized optical coherence tomography (OCT). Compared with WT littermates, the APCMin mutated mice developed myopia (average -4.64 D) on P84 which was associated with increased vitreous chamber depth (VCD). Furthermore, retinal and scleral changes appear in these mice along with: 1) axial length shortening; 2) increased retinal cell proliferation; 3) and decreased tyrosine hydroxylase (TH) expression, the rate-limiting enzyme of DA synthesis. Scleral collagen fibril diameters became heterogeneous and irregularly organized in the APCMin mice. Western blot analysis showed that scleral alpha-1 type I collagen (col1α1) expression also decreased whereas MMP2 and MMP9 mRNA expression was invariant. These results indicate that defective APC gene function promotes refractive error development. By characterizing in APCMin mice ocular developmental changes, this approach provides novel insight into underlying pathophysiological mechanisms contributing to human myopia development. [ABSTRACT FROM AUTHOR]

Purpose This study investigated whether pilocarpine and cyclopentolate induce changes in ocular biometry of guinea pigs, in order to understand if guinea pigs have a similar response to these two agents as humans do. Methods Under general anaesthesia, refraction, axial components and surface curvature in various optical interfaces of the eye were measured in 10 guinea pigs (age of 2 weeks) at baseline (0 min) and different time points (5, 10, 20, 30, 60, 90 min) after topical administration of pilocarpine or cyclopentolate. The interval between the two drug treatments for the same animals was at least 24 h. Results Eyes treated with pilocarpine developed approximately 6D myopia ( p < 0.001 from 0 to 90 min) with a decrease in anterior lens radius of curvature ( ALRC) ( p < 0.001 from 0 to 90 min, repeated measures anova). This myopic shift was moderately correlated to the decreased ALRC ( r2 = 0.48, p < 0.001). Furthermore, a small but significant increase in the VCD ( p < 0.001 from 0 to 30 min, repeated measures anova) with an unchanged AL ( p = 0.85 from 0 to 90 min, repeated measures anova) after the drug treatment suggested a transient and mild forward movement of the lens. Cyclopentolate dilated the pupil in all eyes ( p < 0.001 from 0 to 90 min, repeated measures anova) but did not change other ocular parameters. Conclusions The muscarinic agonist, pilocarpine induced a myopic shift mainly due to a decrease in ALRC, suggesting that guinea pigs have an accommodative mechanism similar to that in humans. The minimal changes produced by cyclopentolate could be due to the use of general anaesthesia, which may have reduced the susceptibility of the eye to topical cyclopentolate in the induction of cycloplegia. [ABSTRACT FROM AUTHOR]

Highlights: [•] The choroid of guinea pigs responds to imposed chromatic defocus. [•] The ERG b-wave reflects the differences in chromaticity of light used to imposed chromatic defocus. [•] Red light elicits an ERG with a poor signal-to-noise ratio in the guinea pig, suggesting poor sensitivity. [•] Blue light inhibits eye growth perhaps by enhancing the ON pathway. [•] Even when illuminances were matched by ERG, lenses were poorly compensated in red light, compared to blue light. [Copyright &y& Elsevier]

The process of eye axis lengthening in myopic eyes is regulated by multiple mechanisms in the retina, and horizontal cells (HCs) are an essential interneuron in the visual regulatory system. Wherein intracellular Ca2+ plays an important role in the events involved in the regulatory role of HCs in the retinal neural network. It is unknown if intracellular Ca2+ regulation in HCs mediates changes in the retinal neural network during myopia progression. We describe here a novel calcium fluorescence indicator system that monitors HCs' intracellular Ca2+ levels during form-deprivation myopia (FDM) in mice. AAV injection of GCaMP6s, as a protein calcium sensor, into a Gja10-Cre mouse monitored the changes in Ca2+signaling in HC that accompany FDM progression in mice. An alternative Gja10-Cre/Ai96-GCaMP6s mouse model was created by cross mating Gja10-Cre with Ai96 mice. Immunofluorescence imaging and live imaging of the retinal cells verified the identity of these animal models. Changes in retinal horizontal cellular Ca2+ levels were resolved during FDM development. The numbers of GCaMP6s and the proportion of HCs were tracked based on profiling changes in GCaMP6s+calbindin+/calbindin+ coimmunostaining patterns. They significantly decreased more after either two days (P < 0.01) or two weeks (P < 0.001) in form deprived eyes than in the untreated fellow eyes. These decreases in their proportion reached significance only in the retinal central region rather than also in the retinal periphery. A novel approach employing a GCaMP6s mouse model was developed that may ultimately clarify if HCs mediate Ca2+ signals that contribute to controlling FDM progression in mice. The results indicate so far that FDM progression is associated with declines in HC Ca2+ signaling activity. • FDM downregulates calcium level in horizontal cells either two days or two weeks. • Downregulation of Ca2+ in horizontal cells is region-specific only in the retinal center. • GCaMP6 mouse model can clarify HCs mediate Ca2+ signals that contribute to controlling FDM. [ABSTRACT FROM AUTHOR]

Abstract: Mitochondrial m.14484T>C (MT-ND6) mutation has been associated with Leber's hereditary optic neuropathy. Previous investigations revealed that the m.14484T>C mutation is a primary factor underlying the development of optic neuropathy but is not sufficient to produce a clinical phenotype. However, mitochondrial haplogroups have been proposed to modulate the phenotypic manifestation of the m.14484T>C mutation. Here, we performed the clinical, genetic evaluation and complete mitochondrial genome sequence analysis of 41 Han Chinese pedigrees carrying the m.14484T>C mutation. These families exhibited a wide range of penetrances and expressivities of optic neuropathy. The average ratio between affected male/female matrilineal relatives from 41 families was 2:1. The penetrance of optic neuropathy in these Chinese pedigrees ranged from 5.6% to 100%, with the average of 23.8%. Furthermore, the age-of-onset for optic neuropathy varied from 4 to 44years, with the average of 19.3years. Sequence analysis of their mitochondrial genomes identified distinct sets of polymorphisms belonging to ten Eastern Asian haplogroups, indicating that the m.14484T>C mutation occurred through recurrent origins and founder events. We showed that mitochondrial haplogroups M9, M10 and N9 increased the penetrance of optic neuropathy in these Chinese families. In particular, these mitochondrial haplogroup specific variants: m.3394T>C (MT-ND1), m.14502T>C (MT-ND4) and m.14693A>G (MT-TE) enhanced the penetrance of visual loss in these Chinese families. These data provided the direct evidence that mitochondrial modifiers modulate the variable penetrance and expressivity of optic neuropathy among Chinese pedigrees carrying the m.14484T>C mutation. [Copyright &y& Elsevier]

Myopia is a refractive error of the eye that is prevalent worldwide. The most extreme form, high myopia, is usually associated with other ocular disorders such as retinal detachment, macular degeneration, cataract, and glaucoma, and is one of leading causes of blindness. The etiology is complex and has not been fully elucidated. In this study, we identified a novel missense variant of the CCDC111 gene (NM_152683.2: c.265T > G; p.Y89D) in a high myopia family by exome sequencing. The variant was identified in 4 patients from an additional 270 sporadic high myopia patients, but not found in 270 controls. The amino acid is highly conserved across species, and variants giving rise to amino acid substitutions are predicted to be functionally damaging. The CCDC111 gene was ubiquitously expressed in primary cell cultures from human eye tissue, including corneal epithelial cells, choroidal melanoma cells, scleral fibroblasts, retinal epithelial cells, retinal Müller cells, and lens capsule epithelial cells. In summary, our results suggested that the CCDC111 may be a susceptibility gene for high myopia. [ABSTRACT FROM AUTHOR]

The development of myopia is associated with decreased ocular scleral collagen synthesis in humans and animal models. Collagen synthesis is, in part, under the influence of cyclic adenosine monophosphate (cAMP). We investigated the associations between cAMP, myopia development in guinea pigs, and collagen synthesis by human scleral fibroblasts (HSFs). Form-deprived myopia (FDM) was induced by unilateral masking of guinea pig eyes. Scleral cAMP levels increased selectively in the FDM eyes and returned to normal levels after unmasking and recovery. Unilateral subconjunctival treatment with the adenylyl cyclase (AC) activator forskolin resulted in a myopic shift accompanied by reduced collagen mRNA levels, but it did not affect retinal electroretinograms. The AC inhibitor SQ22536 attenuated the progression of FDM. Moreover, forskolin inhibited collagen mRNA levels and collagen secretion by HSFs. The inhibition was reversed by SQ22536. These results demonstrate a critical role of cAMP in control of myopia development. Selective regulation of cAMP to control scleral collagen synthesis may be a novel therapeutic strategy for preventing and treating myopia. [ABSTRACT FROM AUTHOR]

Abstract: Embryonic eyelid closure involves forward movement and ultimate fusion of the upper and lower eyelids, an essential step of mammalian ocular surface development. Although its underlying mechanism of action is not fully understood, a functional mitogen-activated protein kinase kinase kinase 1 (MAP3K1) is required for eyelid closure. Here we investigate the molecular signatures of MAP3K1 in eyelid morphogenesis. At mouse gestational day E15.5, the developmental stage immediately prior to eyelid closure, MAP3K1 expression is predominant in the eyelid leading edge (LE) and the inner eyelid (IE) epithelium. We used laser capture microdissection (LCM) to obtain highly enriched LE and IE cells from wild type and MAP3K1-deficient fetuses and analyzed genome-wide expression profiles. The gene expression data led to the identification of three distinct developmental features of MAP3K1. First, MAP3K1 modulated Wnt and Sonic hedgehog signals, actin reorganization, and proliferation only in LE but not in IE epithelium, illustrating the temporal-spatial specificity of MAP3K1 in embryogenesis. Second, MAP3K1 potentiated AP-2α expression and SRF and AP-1 activity, but its target genes were enriched for binding motifs of AP-2α and SRF, and not AP-1, suggesting the existence of novel MAP3K1-AP-2α/SRF modules in gene regulation. Third, MAP3K1 displayed variable effects on expression of lineage specific genes in the LE and IE epithelium, revealing potential roles of MAP3K1 in differentiation and lineage specification. Using LCM and expression array, our studies have uncovered novel molecular signatures of MAP3K1 in embryonic eyelid closure. [Copyright &y& Elsevier]

High myopia, which is extremely prevalent in the Chinese population, is one of the leading causes of blindness in the world. Genetic factors play a critical role in the development of the condition. To identify the genetic variants associated with high myopia in the Han Chinese, we conducted a genome-wide association study (GWAS) of 493,947 SNPs in 1088 individuals (419 cases and 669 controls) from a Han Chinese cohort and followed up on signals that were associated with p < 1.0 × 10−4 in three independent cohorts (combined, 2803 cases and 5642 controls). We identified a significant association between high myopia and a variant at 13q12.12 (rs9318086, combined p = 1.91 × 10−16, heterozygous odds ratio = 1.32, and homozygous odds ratio = 1.64). Furthermore, five additional SNPs (rs9510902, rs3794338, rs1886970, rs7325450, and rs7331047) in the same linkage disequilibrium (LD) block with rs9318086 also proved to be significantly associated with high myopia in the Han Chinese population; p values ranged from 5.46 × 10−11 to 6.16 × 10−16. This associated locus contains three genes—MIPEP, C1QTNF9B-AS1, and C1QTNF9B. MIPEP and C1QTNF9B were found to be expressed in the retina and retinal pigment epithelium (RPE) and are more likely than C1QTNF9B-AS1 to be associated with high myopia given the evidence of retinal signaling that controls eye growth. Our results suggest that the variants at 13q12.12 are associated with high myopia. [Copyright &y& Elsevier]